此应用程序的某些内容目前无法使用。
如果这种情况持续存在,请联系我们反馈与联系
1. (WO2019066993) WARPAGE MITIGATION STRUCTURES CREATED ON SUBSTRATE USING HIGH THROUGHPUT ADDITIVE MANUFACTURING
注:相关文本通过自动光符识别流程生成。凡涉及法律问题,请以 PDF 版本为准

WARPAGE MITIGATION STRUCTURES CREATED ON SUBSTRATE USING HIGH THROUGHPUT ADDITIVE MANUFACTURING

FIELD

Embodiments relate to semiconductor devices. More particularly, the embodiments relate to packaging semiconductor devices with substrate integrated posts and integrated heat spreader customization using high throughput additive manufacturing for enhanced package

thermomechanics; semiconductor devices with a highly conductive layer deposited on dies using high throughput additive deposition; and semiconductor device stiffeners directly disposed on a substrate using high throughput additive deposition.

BACKGROUND

Packaging semiconductor devices presents several challenges. One such challenge is encountered with the demand for miniaturization of semiconductor devices, continually requiring thinner form factors. The resulting packages suffer from warpage generated as a result of the mismatch in the coefficient of thermal expansion (CTE) between a thin die and a substrate.

Package warpage is a significant challenge as it impacts the ability to handle the package during assembly steps. In addition, package warpage produces yield losses during reflow, which are typically caused by open (non-contacting) second layer interconnects in the locations having the maximum warpage-induced vertical displacement. As such, package warpage is therefore a major problem for ultra-thin package designs.

Recently, one of the main packaging solutions to control the warpage of ultra-thin packages is to attach a discrete stiffener (e.g., a discrete stiffener having a picture frame design) onto the substrate with an adhesive layer, such as epoxy, using pick and place equipment. This packaging solution has several problems, including: (i) requiring the sequential assembly of a stiffener to each package (typically after forming an epoxy layer to attach the stiffener) which thus adds assembly steps and reduces throughput; (ii) using an epoxy layer to attach the stiffener, which limits the effectiveness of warpage reduction as epoxy has a lower modulus than the stiffener material which is typically metal (i.e. , resulting in a slightly compliant mechanical coupling between the substrate and stiffener itself); (iii) handling of thin discrete stiffeners (e.g., roughly 50 urn or less) which is extremely challenging; (iv) using a one-piece stiffener to reduce the amount of handling and number of assembly steps, which limits the available shapes of the discrete stiffener to be used and also consumes additional surface area of the substrate that could be used for other components; (v) the limited selection of materials (e.g. , stainless steel or copper foil) available to form the discrete stiffener; (vi) poor adhesion of the discrete stiffener to other materials (e.g. , epoxy molding compounds), making the combination of using the stiffener and subsequent molding encapsulation not a feasible option for many architectures due to delamination; and (vii) forming the stiffener on the substrate by using semi-additive deposition (e.g. , lithography and plating), which limits the available materials that can be used to form the stiffener (e.g., copper (Cu) or few other metals) and is typically a slow process (e.g.,

electroplating tens of microns can take hours) requiring expensive lithography steps and equipment.

Moreover, packaging semiconductor devices with integrated heat spreaders (IHS) or lids also present several problems. One such problem in multi chip packages (MCPs) is that the lid typically bottoms out on one of the semiconductor chips or dies that are assembled on the package, achieving the lowest possible thermal interface material (TIM) bondline thickness (BLT) and lowest TIM thermal resistance above that die while producing larger TIM BLT and higher TIM thermal resistance above other chips or die in the package.

For thermal management, packaging solutions may use polymer thermal interface material (PTIM) between the dies and the lid (or IHS). While the thermal performance of PTIMs is sufficient in some segments, new high power segments are emerging which require TIMs with lower thermal resistance (e.g., solder TIM). One problem with using solder TIM (STIM) is that it does not wet bare silicon (Si) and thus requires die backside metallization (BSM), which increases the complexity and cost of the backend fabrication process by requiring the deposition of titanium gold (Ti/Au) on the wafer prior to singulation. Likewise, other types of TIMs with higher conductivity than PTIM, such as high metal filler epoxy TIM or sinterable paste, have poor adhesion to polished Si and require surface functionalization or treatment of the Si to be used effectively.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments described herein are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar features.

Furthermore, some conventional details have been omitted so as not to obscure from the inventive concepts described herein.

Figure 1A is a cross-sectional view of a semiconductor package having a lid, one or more dies, one or more posts, and a substrate, according to one embodiment. Figure IB is a corresponding plan view of the semiconductor package without the lid, according to one embodiment.

Figure 2A is a cross-sectional view of a semiconductor package having a lid, one or more

dies, a post, and a substrate, according to one embodiment. Figure 2B is a corresponding plan view of the semiconductor package without the lid, according to one embodiment.

Figure 3A is a cross-sectional view of a semiconductor package having a lid, a die, one or more posts, and a substrate, according to one embodiment. Figure 3B is a corresponding plan view of the semiconductor package without the lid, according to one embodiment.

Figures 4-6 are plan views of semiconductor packages with one or more dies and one or more posts, according to some embodiments.

Figures 7A and 7B are cross-sectional views of a semiconductor package having a lid, one or more dies, one or more die-side capacitors (DSCs), one or more posts, and a substrate, according to one embodiment. Figure 7C is a corresponding plan view of the semiconductor package without the lid, according to one embodiment.

Figure 8 is a process flow illustrating a method of forming a semiconductor package having a lid, one or more dies, one or more posts, and a substrate, according to one embodiment.

Figure 9 is a cross-sectional view of a semiconductor package having a lid, one or more dies, a high throughput additively manufactured (HTAM) layer, and a substrate, according to one embodiment.

Figure 10 is a cross-sectional view of a semiconductor package having a lid, one or more dies, a HTAM leg, and a substrate, according to one embodiment.

Figure 11 is a plan view of a bottom surface of a lid with one or more HTAM legs showing their locations with respect to one or more die shadows, according to one embodiment.

Figure 12 is a cross-sectional view of a semiconductor package having a lid, one or more dies, one or more HTAM layers, and a substrate, according to one embodiment.

Figure 13 is a cross-sectional view of a semiconductor package having a lid, one or more dies, one or more HTAM legs, and a substrate, according to one embodiment.

Figure 14 is a process flow illustrating a method of forming a semiconductor package having a lid, one or more dies, one or more HTAM layers, and a substrate, according to one embodiment.

Figure 15 is a cross-sectional view of a semiconductor package having a lid, a die, a highly conductive (HC) intermediate layer, a TIM layer, and a substrate, according to one embodiment.

Figure 16A is a cross-sectional view of a semiconductor package having a lid, a die, one or more HC intermediate layers, one or more TIM layers, and a substrate, according to one embodiment. Figures 16B is a corresponding plan view of the die and the HC intermediate layers, according to one embodiment. Figures 16C is a corresponding plan view of the die and the HC intermediate layers, according to an alternative embodiment.

Figure 17 is a cross-sectional view of a semiconductor package having a lid, one or more dies, one or more HC intermediate layers, one or more TIM layers, and a substrate, according to one embodiment.

Figure 18 is a cross-sectional view of a semiconductor package having a lid, one or more stacked dies, one or more HC intermediate layers, one or more TIM layers, and a substrate, according to one embodiment.

Figure 19 is a process flow illustrating a method of forming a semiconductor package having a lid, one or more dies, one or more HC intermediate layers, one or more TIM layers, and a substrate, according to one embodiment.

Figure 20 is a cross-sectional view of a semiconductor package having a die, a plurality of stiffeners, and a substrate, according to one embodiment.

Figure 21 is a cross-sectional view of a semiconductor package having one or more dies, a plurality of stiffeners, and a substrate, according to one embodiment.

Figures 22A and 22B are plan views of semiconductor packages having one or more dies, a plurality of stiffeners with different shapes, and a substrate, according to some embodiments.

Figure 23 is a cross-sectional view of a semiconductor package having a die, a plurality of stiffeners, and a substrate, according to one embodiment.

Figure 24 is a cross-sectional view of a semiconductor package having one or more dies, a plurality of stiffeners, a molding layer, and a substrate, according to one embodiment.

Figure 25 is a process flow illustrating a method of forming a semiconductor package having a die, a plurality of stiffeners, and a substrate, according to one embodiment.

Figure 26 is a schematic block diagram illustrating a computer system that utilizes a device package with a die, a plurality of stiffeners, and a substrate, according to one

embodiment.

DETAILED DESCRIPTION

Described below are ways for forming semiconductor devices (or packages) with substrate integrated posts, integrated heat spreaders, highly conductive layers deposited on dies, and substrate-integrated stiffeners. Specifically, the semiconductor packages described herein include substrate integrated posts and integrated heat spreaders that are customized using high throughput additive manufacturing (AM) for enhanced package thermomechanics. Additionally, the semiconductor packages described herein may also include forming highly conductive layers on one or more dies using high throughput additive deposition (e.g., a cold spray (CS) process). Likewise, the semiconductor packages described herein also include stiffeners directly disposed on the substrate (and/or the die) using high throughput additive deposition.

In the following description, various aspects of the illustrative implementations will be described using terms commonly employed by those skilled in the art to convey the substance of their work to others skilled in the art. However, it will be apparent to those skilled in the art that the present embodiments may be practiced with only some of the described aspects. For purposes of explanation, specific numbers, materials and configurations are set forth in order to provide a thorough understanding of the illustrative implementations. However, it will be apparent to one skilled in the art that the present embodiments may be practiced without the specific details. In other instances, well-known features are omitted or simplified in order not to obscure the illustrative implementations.

Various operations will be described as multiple discrete operations, in turn, in a manner that is most helpful in understanding the present embodiments, however, the order of description should not be construed to imply that these operations are necessarily order dependent. In particular, these operations need not be performed in the order of presentation.

The present embodiments may include substrate integrated posts, integrated heat spreaders, and/or highly conductive layers formed using a CS process that enhance packaging solutions. For example, as described herein, the present embodiments help to solve the problems of dealing with complex lid designs for each and every package (especially in multi-chip packages (MCPs)) and address thermal and reliability issues. Likewise, the present embodiments also enable new architectures and processes that allow the use of solder thermal interface materials (STIMs) and other novel or non-standard thermal interface materials (TIMs) for improved thermal management, binning, and performance over polymer TIM (PTIM), while eliminating the need for traditional wafer-level backside metallization (BSM) to enable wettability or special surface functionalization to improve adhesion.

According to most embodiments, the semiconductor packages (also referred to as device packages) facilitate packaging solutions by providing (i) a main universal lid (e.g. , a flat lid or a large lid with legs only on its outer periphery) that may only be dependent on package size (hence has the same design for different packages of the same size) and may be

manufactured/assembled using a standard direct lid attach (DLA) process (e.g. , stamping); and (ii) one or more posts (or frames) surrounding each die, integrated with and disposed on the substrate, and mechanically coupled to the main lid (e.g. , using an adhesive layer).

The present embodiments further enhance packaging solutions by enabling a cost-efficient solution that allows a single universal lid design and varying TIM materials to be used across multiple platforms and technologies. In particular, some of the advantages of the present embodiments include: (i) a discrete stiffener and its associated assembly steps are not needed as the posts are manufactured using substrate or panel level manufacturing processes; (ii) stronger mechanical coupling between the substrates and posts leading to lower thermomechanical stresses between the dies and flat lid edges and thus improved TIM thermal performance and reliability; (iii) improved flexibility to create multiple separate posts instead of being limited to a single connected picture frame design (note that this is especially advantageous as it allows the optimization of the post designs for thermomechanical performance, while minimizing the area the posts occupy on the substrate and thus increasing the substrate area for other components (e.g. , additional die, die-side capacitors, etc.)); (iv) the flexibility to form the posts from one or more different materials (e.g. , metals, metal alloys, metal/ceramic composites, polymers, polymer-metal, polymer-ceramic composites, etc.) rather than being limited to metal (e.g. , stainless steel or Cu) that is typically used to form discrete stiffeners; (v) a reduction of the die overhang by creating posts that are near each die, thus reducing warpage, TIM stress, and TIM degradation during reliability testing; (vi) customization features/components on the universal lid using high throughput AM; and (vii) a cost-efficient process that allows the use of low-cost lids with standard (universal) designs which can then be customized with AM steps (e.g. , depositing and forming the custom lid features and/or posts, at a faster rate, with their desired

differentiating features in a single-step using a single equipment), and also allows great flexibility in terms of material selections and patterns.

According to most embodiments, Figures 1 - 8 illustrate semiconductor packages that include substrates with one or more integrated posts for enhanced thermomechanics.

Figure 1A illustrates a cross-sectional view of a semiconductor package 100. For one embodiment, the semiconductor package 100 has a lid 102, one or more dies 105-106, posts 110, and a substrate 101. Correspondingly, Figure IB shows a plan view of the semiconductor package 100 - with the lid 102 omitted in this view - having the dies 105-106 and posts 110 disposed on a top surface 101a of the substrate 101, according to one embodiment.

As used herein, a "post" (also referred to as a substrate integrated post) refers to a structure or frame directly disposed on a substrate - without the use of any adhesive layer -where the post may be adjacent to or surround one or more dies on the substrate. For example, one or more posts (e.g. , posts 110 of Figure 1A) may be customized for each die and package to provide the necessary mechanical characteristics needed to avert thermal and reliability issues. In addition, according to most embodiments, the posts may be used with a main/single universal lid (e.g. , lid 102 of Figure 1A) that may be shared across multiple packages and technologies. That is, for most embodiments, the posts are formed using substrate or panel-level processes and are thus customized for each package design to optimize the package's thermomechanical response, while allowing the same universal lid to be attached to the posts and used across different devices/products. This simplifies the lid design and assembly processes and ensures that the

thermal and reliability issues are addressed by incorporating the posts.

Referring now to Figure 1A, a semiconductor package 100 (also referred to as a device package) has a plurality of posts 110 disposed on a top surface 101a of a substrate 101. For one embodiment, each post 110 has a top surface 110a and a bottom surface 110b that is opposite from the top surface 110a. According to some embodiments, the semiconductor package 100 also has one or more dies 105-106 disposed on the top surface 101a of the substrate 100. For most embodiments, the one or more dies 105-106 are located adjacent to (or surrounding) the posts 110 on the substrate 101. According to most embodiments, a lid 102 is disposed above the posts 110 and the dies 105-106 on the substrate 100, where the lid 102 has a top surface 102a and a bottom surface 102b that is opposite from the top surface 102a. Additionally, an adhesive layer 120 may be disposed on the top surface 110a of each post 110, where the adhesive layer 120 attaches (or couples) the bottom surface 102b of the lid 102 and the top surfaces 110a of the posts 110 (i.e. , the adhesive layer 120 forms a mechanical coupling between the posts 110 and the lid 102).

According to some embodiments, the substrate 101 may include, but is not limited to, a package, a substrate, and a printed circuit board (PCB). For one embodiment, the substrate 101 is a PCB. For one embodiment, the PCB is made of an FR-4 glass epoxy base with thin copper foil laminated on both sides (not shown). For certain embodiments, a multilayer PCB can be used, with pre-preg and copper foil (not shown) used to make additional layers. For example, the multilayer PCB may include one or more dielectric layers, where each dielectric layer can be a photosensitive dielectric layer (not shown). For some embodiments, holes (not shown) may be drilled in substrate 101. For one embodiment, the substrate 101 may also include conductive copper traces, metallic pads, and holes (not shown).

For one embodiment, each of the one or more dies 105-106 includes, but is not limited to, a semiconductor die, an integrated circuit, a CPU, a microprocessor, and a platform controller hub (PCH), a memory, and a field programmable gate array (FPGA). Note that each of the dies 105-106 may be similar dies or differ in size (e.g. , having varying z-heights or areas). For most embodiments, the dies 105-106 may be disposed adjacent to the posts 110. For example, a post (or posts) may surround one or more dies (as shown in Figures 1A-1B, 3A-3B, and 4-7), or the post (or posts) may be between the dies (as shown in Figures 1A-1B, 2A-2B, and 4-6).

According to some embodiments, the lid 102 may be formed as a flat lid with no legs or a lid with legs on the outer periphery of the lid (as shown in Figures 2A-2B). For example, the lid 102 may be formed based on the desired package size (i.e. , has the same design for different packages of the same size) and assembled using a standard DLA process. For one embodiment, as shown in Figure 1A, the lid 102 is a flat lid that is coupled to the posts 110 on the substrate 101 using an adhesive layer 120, thus reducing the thermomechanical stresses in TIM 130 at the edges of the dies 105-106 (compared to using a standard lid (or IHS) with monolithic legs). The lid 102 may be formed from a thermally conductive material, such as metal. For example, the lid

102 may be formed from at least one of copper, aluminum, steel, nickel, any other metal, a metal alloy, any other conductive material, or any combination thereof.

For one embodiment, the adhesive layer 120 may be used to couple (mechanically and/or thermally) the posts 110 and the lid 102, where the adhesive layer 120 may be formed on the top surface 110a of each post 110. The adhesive layer 120 may be formed with an epoxy material or any compliant adhesive. For some embodiments, one or more TIMs 130 may be formed on the dies 105-106 and couple the dies 105-106 to the bottom surface 102b of the lid 102 thermally and/or mechanically. The TIMs 130 (or TIM layers) may include, but are not limited to, a PTIM, an epoxy, a liquid phase sintering (LPS) paste, a solder paste or TIM, any other TIM material, or any combination thereof. For one embodiment, a thickness or BLT of the TIM 130 on die 105 may be equal or substantially equal to a thickness or BLT of TIM 130 on die 106. For another embodiment, a thickness or BLT of the TIM 130 on die 105 may be different from a thickness or BLT of TIM 130 on die 106 (i.e. , in addition to their heat dissipation functions, the TIMs 130 may be used to compensate for a z-height variation in one or more dies).

According to some embodiments, the posts 110 are disposed (and/or formed) on the substrate 101. For example, the posts 110 may be integrated with, and manufactured onto the substrate 101 and mechanically coupled to the lid 102 with the adhesive layer 120. The posts 110 may be formed to have one or more different shapes, such as a picture frame, a separator, a round pillar, an H or I shape, etc. The posts 110 may be formed using materials such as metals (e.g. , copper (Cu), aluminum (AI), titanium (Ti), nickel (Ni), etc.), metal alloys (e.g. , stainless steel), metal/ceramic composites (e.g., Cu/diamond, Cu/alumina), and/or any combination thereof.

For most embodiments, the posts 110 can be created on the substrate 101 at the panel or unit level. In addition, the posts 110 may be formed with one or more different materials, including metals, metal alloys, and/or metal/ceramic composites. For one embodiment, the posts 110 may be formed using AM methods, such as cold spray. For example, to form the posts 110, powders of the one or more materials to be deposited/formed are accelerated through a nozzle at high speeds, forming a mechanical bond upon impact with the top surface 101a of the substrate 101. Patterning can be achieved by controlling the nozzle dimensions and movement, and/or by spraying the powders through a shadow mask (not shown) with the desired features and/or shapes. Note that this approach allows flexibility in material choice as multiple material powders can be combined and used to form posts (e.g. , posts 110 of Figure 1A) with the desired

thermomechanical properties. For another embodiment, the posts 110 may be formed only with metals by using standard substrate manufacturing methods (e.g. , semi-additive manufacturing).

For other embodiments, the posts 110 may be formed with polymers, polymer-metals, and/or polymer-ceramic composites (e.g. , metal-filled or ceramic-filled polymers or resins, epoxy molding compounds, etc.), which may be patterned to the desired shape using dispensing or molding (e.g., compression molding). For alternative embodiments, the posts 110 may also be formed with one or more layers of different materials (e.g., epoxy, metal, ceramic,

nanocrystalline powders, etc.), which may be produced/formed through any of the processes described herein (or in which some of the layers are picked and placed as discrete components).

Note that the semiconductor package 100, as shown in Figure 1 A, may include fewer or additional packaging components based on the desired packaging design.

Referring now to Figure IB, a top view of the semiconductor package 100 is shown without a lid (e.g., lid 102 of Figure 1A), an adhesive layer (e.g., adhesive layer 120 of Figure 1A), and a TIM layer (e.g., TIMs 130 of Figure 1A). As shown in Figure IB, the one or more dies 105-106 are disposed on the top surface 101a of the substrate 101 and surrounded by the one or more posts 110.

The posts 110 are formed with two shapes: four small rectangular posts 110 are located on the outer periphery (or edges) of the substrate 101, and a large rectangular post 110 (also referred to as a large separator post) is located between both dies 105-106 on the substrate 101. For other embodiments, the posts 110 may have other shapes and sizes such as picture frame posts, squared-shaped posts, L-shaped corner posts (or L-shaped posts), round pillars, multiple smaller separators (rather than a large separator), H-shaped separator posts (or H-shaped posts), T-shaped separator posts (or T-shaped posts), and/or any combination thereof. The posts 110 may have a similar (or equal) surface area or different surface areas (and different z-heights), depending on the desired thermomechanical properties and/or package design.

Note that the semiconductor package 100, as shown in Figure IB, may include fewer or additional packaging components based on the desired packaging design.

Figure 2A is a cross-sectional view of a semiconductor package 200 having a lid 202, one or more dies 205-206, a post 210, and a substrate 201, according to one embodiment. Figure 2B is a corresponding plan view of the semiconductor package 200 without the lid 202, according to one embodiment. Note that the semiconductor package 200 of Figures 2A and 2B is similar to the semiconductor package 100 of Figures 1A and IB, however the semiconductor package 200 has the lid 202 with legs 202c-d on the outer periphery of the substrate 201.

Referring now to Figure 2A, the semiconductor package 200 has the post 210 disposed on a top surface 201a of the substrate 201. For one embodiment, the post 210 has a top surface 210a and a bottom surface 210b. The semiconductor package 200 further includes dies 205-206 disposed on the top surface 201a of the substrate 201. As shown in Figure 2A, the dies 205-206 are located adjacent to the post 210 on the substrate 201. The lid 202 may be disposed above the post 210 and the dies 205-206 on the substrate 201, where the lid 202 has a top surface 202a and a bottom surface 202b. Additionally, an adhesive layer 220 may be disposed on the top surface 210a of the post 210, where the adhesive layer 220 is formed between the bottom surface 202b of the lid 202 and the top surface 210a of the post 210.

For one embodiment, the post 210 may be formed as a large rectangular separator between the dies 205-206. For other embodiments, the post 210 may have other shapes and sizes, such as one or more smaller separator posts with a round shape, L-shape, T-shape, H-shape, and/or any combination thereof. For some embodiments, the lid 202 may be formed as a flat lid having legs 202c-d on the outer periphery of the lid 202. For example, the legs 202c-d of the lid may be formed to have one or more different shapes, where the legs 202c-d may include rectangular shapes located on the edges of the lid 202, a picture frame shape on the outer edges of the lid 202 (e.g. , coupling both legs 202c-d), round pillars located on the edges of the lid 202, L-shaped comers on the lid 202, or any desired shape and size. For one embodiment, the lid 202 may be coupled to the post 210 on the substrate 201 using the adhesive layer 220.

According to some embodiments, the lid 202 may be coupled to the substrate 201 with a sealant 225 (also referred to as a sealant layer). For one embodiment, the sealant 225 is formed between the top surface 201a of the substrate and the bottom surfaces of the legs 202c-d. For some embodiments, the sealant 225 may provide some degree of thermal coupling between the lid 202 and the substrate 201, but the sealant's 225 main function is to provide a structural or mechanical coupling between the lid 202 and the substrate 201. The sealant 225 may be formed from an adhesive material that contains thermally conductive particles, a silicone-based sealant material, an epoxy-based sealant material, or any other sealant materials known in the art.

For some embodiments, one or more TIMs 230 may be formed on the dies 205-206 and couple the dies 205-206 to the bottom surface 202b of the lid 202 thermally and/or mechanically. For one embodiment, the BLT of the TIM 230 on die 205 may be equal or substantially equal to the BLT of TIM 230 on die 206. For another embodiment, the BLT of the TIM 230 on die 205 may be different from the BLT of TIM 230 on die 206 (e.g. , when the dies have different z-heights).

According to some embodiments, the post 210 is disposed on the top surface 201a of the substrate 201. For example, the post 210 may be integrated with, and manufactured onto the substrate 201 and mechanically coupled to the lid 202 with the adhesive layer 220. For some embodiments, the post 210 may be formed as a large rectangular separator or multiple smaller

separators between the dies 205-206.

Note that the semiconductor package 200, as shown in Figure 2A, may include fewer or additional packaging components based on the desired packaging design.

Referring now to Figure 2B, a top view of the semiconductor package 200 is shown without a lid (e.g., lid 202 of Figure 2A), an adhesive layer (e.g., adhesive layer 220 of Figure 2A), a sealant layer (e.g., sealant 225 of Figure 2A), and a TIM layer (e.g., TIMs 230 of Figure 2 A). As shown in Figure 2B, the dies 205-206 are disposed on the top surface 201a of the substrate 201 and adjacent to the post 210.

Note that the semiconductor package 200, as shown in Figure 2B, may include fewer or additional packaging components based on the desired packaging design.

Figure 3 A is a cross-sectional view of a semiconductor package 300 having a lid 302, a die 305, one or more posts 310, and a substrate 301, according to one embodiment. Figure 3B is a corresponding plan view of the semiconductor package 300 without the lid 302, according to one embodiment. Note that the semiconductor package 300 of Figures 3A and 3B is similar to the semiconductor packages 100 of Figures 1A and IB and 200 of Figures 2A and 2B, however the semiconductor package 300 includes a single die 305.

Referring now to Figure 3A, the semiconductor package 300 has the posts 310 disposed on a top surface 301a of the substrate 301. For one embodiment, each of the posts 310 has a top surface 310a and a bottom surface 310b. The semiconductor package 300 further includes the die 305 disposed on the top surface 301a of the substrate 301. As shown in Figure 3A, the die 305 is surrounded with the posts 310 and located roughly on a central region of the substrate 301. The lid 302 may be disposed above the posts 310 and the die 305 on the substrate 301, where the lid 302 has a top surface 302a and a bottom surface 302b. Additionally, an adhesive layer 320 may be disposed on the top surface 310a of the posts 310, where the adhesive layer 320 is formed between the bottom surface 302b of the lid 302 and the top surfaces 310a of the posts 310.

For one embodiment, the posts 310 may be formed as one or more rectangles (or squares) on the outer edges of the substrate 301 and surrounding the die 305. For example, the lid 302 may be a flat lid that is coupled to the posts 310 on the substrate 301 with the adhesive layer 320, such that the thermomechanical stresses in TIM 330 at the edges of die 305 are reduced.

For some embodiments, the TIM 330 may be formed on the die 305, coupling the die 305 to the bottom surface 302b of the lid 302 thermally and/or mechanically. For one embodiment, the BLT of the TIM 330 on die 305 may be equal or substantially equal to the BLT of the adhesive layer 320. For another embodiment, the BLT of the TIM 330 may be different than the BLT of the adhesive layer 320 (e.g. , where the different BLTs of the TIM and adhesive layer may be accommodating for the difference in z-height between the die 305 and the posts 310).

Note that the semiconductor package 300, as shown in Figure 3A, may include fewer or additional packaging components based on the desired packaging design.

Referring now to Figure 3B, a top view of the semiconductor package 300 is shown without a lid (e.g., lid 302 of Figure 3 A), an adhesive layer (e.g., adhesive layer 320 of Figure 3 A), and a TIM layer (e.g., TIM 330 of Figure 3A). As shown in Figure 3B, the die 305 has a large surface area and is disposed on the top surface 301a of the substrate 301. For one embodiment, the die 305 is surrounded by posts 310 formed on each comer of the substrate 301.

Note that the semiconductor package 300, as shown in Figure 3B, may include fewer or additional packaging components based on the desired packaging design.

Figures 4-6 are plan views of semiconductor packages 400, 500, and 600, accordingly, where the views do not include a lid, an adhesive layer, and a TIM layer, according to some embodiments. Note that the semiconductor packages 400, 500, and 600 of Figures 4 - 6 are similar to the semiconductor packages 100 of Figures 1A and IB, 200 of Figures 2A and 2B, and 300 of Figures 3 A and 3B.

Referring now to Figure 4, the semiconductor package 400 has one or more dies 405-409 and one or more posts 410a-c disposed on a top surface 401a of a substrate 401. For some embodiments, the posts 410a-c may have one or more different shapes that may be used for different packages to optimize each package's thermomechanical performance. For example, the posts 410a-c may include four L-shaped corner posts 410b, six rectangular posts 410a, and a picture frame post 410c. For most embodiments, the posts 410a-c may be adjacent to or surround one or more of the dies 405-409.

For one embodiment, the posts 410a-c may be formed using AM methods, such as cold spray. For example, the patterning of posts 410a-c can be achieved by controlling the nozzle dimensions and movement, and/or by spraying the one or more powder materials through a shadow mask (not shown) to form the respective shapes (or any other desired features and/or shapes as shown in Figures 5 - 6).

Note that the semiconductor package 400 may include fewer or additional packaging components based on the desired packaging design.

Referring now to Figure 5, the semiconductor package 500 has one or more dies 505-506 and a post 510 disposed on a top surface 501a of a substrate 501. For some embodiments, the post 510 may be an H-shaped separator post. As such, the post 510 is adjacent to and surrounds the one or more dies 505-506.

Note that the semiconductor package 500 may include fewer or additional packaging components based on the desired packaging design.

Referring now to Figure 6, the semiconductor package 600 has one or more dies 605-607

and one or more posts 610a-b disposed on a top surface 601 a of a substrate 601. For some embodiments, the posts 610a-b may have one or more different shapes, including eight round pillar posts 610a located on the periphery of the substrate 601 a and a T-shaped separator post 610b. For most embodiments, the posts 610a-b may be adjacent to and/or surround the dies 605-607, where the post 610b may separate each of the dies 605-607 from one another.

Note that the semiconductor package 600 may include fewer or additional packaging components based on the desired packaging design.

Figure 7A is a cross-sectional view of a semiconductor package 700 along the A - A' axis. Figure 7B is a corresponding cross-sectional view of the semiconductor package 700 along the B - B' axis. Figure 7C is a corresponding plan view of the semiconductor package 700, illustrating both the A - A' axis and B - B' axis. Note that the semiconductor package 700 of Figures 7A - 7C is similar to the semiconductor packages 100 of Figures 1A - IB, 200 of Figures 2A - 2B, 300 of Figures 3 A -3B, and 400, 500, and 600 of Figures 4 - 6, however the semiconductor package 700 also includes one or more die-side capacitors (DSC) 756 disposed on a top surface 701 a of a substrate 701.

According to some embodiments, the semiconductor package 700 may illustrate some of the advantages of using multiple, separate smaller posts (e.g. , compared to a lid with continuous legs around the entire periphery of the lid, or a discrete picture frame stiffener assembled to the substrate via an adhesive layer), such as an increase in the available surface area on the substrate that allows the incorporation of other components whose thickness is less than the substrate to lid vertical separation. This is shown in Figures 7A - 7C with the semiconductor package 700, including a single die package in which one or more DSCs 756 are disposed under the lid shadow in the space between the posts. Note that this is also applicable to MCPs according to similar embodiments.

Referring now to Figure 7A, the semiconductor package 700 has the posts 710 disposed on the top surface 701a of the substrate 701. For one embodiment, each of the posts 710 has a top surface 710a and a bottom surface 710b. The lid 702 may be disposed above the posts 710 on the substrate 701 , where the lid 702 has a top surface 702a and a bottom surface 702b.

Additionally, an adhesive layer 720 may be disposed on the top surface 710a of the posts 710, where the adhesive layer 720 is formed between the bottom surface 702b of the lid 702 and the top surfaces 710a of the posts 710.

For one embodiment, the posts 710 may be formed as one or more rectangles (or squares) on the outer edges (or comers) of the substrate 701. For example, the lid 702 may be a flat lid that is coupled to the posts 710 on the substrate 701 with the adhesive layer 720.

Referring now to Figure 7B, the cross-sectional view of the semiconductor package 700

is shown along the B - B' axis (parallel to the A - A' axis shown in Figure 7 A). For some embodiments, the semiconductor package also has one or more DSCs 756 disposed on the top surface 701a of the substrate 701, where the DSCs 756 may be located in between the posts (not shown in Figure 7B) and under the shadow of the lid 702 taking advantage of the increased available surface area on the substrate 701. Note that the semiconductor package 700 may include other components aside or in addition to the DSCs 756.

According to some embodiments, the semiconductor package 700 further includes the die 705 disposed on the top surface 701a of the substrate 701. As shown in Figure 7B (and Figure 7C), the die 705 is surrounded with the DSCs 756 (and the posts 710 as shown in Figure 7C) and located roughly on a central region of the substrate 701. The lid 702 may be disposed above the DSCs 756 and the die 705 on the substrate 700. For some embodiments, the TIM 730 may be formed on the die 705, coupling the die 705 to the bottom surface 702b of the lid 702 thermally and/or mechanically.

Referring now to Figure 7C, a top view of the semiconductor package 700 is shown without a lid (e.g., lid 702 of Figures 7A - 7B), an adhesive layer (e.g. , adhesive layer 720 of Figure 7A), and a TIM layer (e.g., TIM 730 of Figure 7B). As shown in Figure 7C, the die 705 has a large surface area and is disposed on the top surface 701a of the substrate 701. For one embodiment, the die 705 is surrounded by posts 710 and DSCs 756 that are disposed on the substrate 701. For another embodiment, the DSCs 756 are disposed between the posts 710 on two edges of the substrate 701 (as shown in Figure 7C) and thus one or more other components may be disposed on the other two edges of the substrate 701.

Note that the semiconductor package 700, as shown in Figures 7A - 7C, may include fewer or additional packaging components based on the desired packaging design.

Figure 8 is a process flow 800 illustrating a method of forming a semiconductor package having a lid, one or more dies, one or more posts, and a substrate, according to one embodiment. Process flow 800 illustrates a method of forming the semiconductor package. For example, process flow 800 shows a method of forming a semiconductor package as shown in Figures 1 -7, using for example AM processes such as cold spray.

At block 805, the process flow 800 disposes a plurality of posts on a substrate, where each post has a top surface and a bottom surface that is opposite from the top surface (as shown in Figure 1A). At block 810, the process flow 800 disposes one or more dies on the substrate, where the one or more dies are adjacent to (or surrounded by) the plurality of posts on the substrate (as shown in Figures 1 A - IB). At block 815, the process flow 800 then disposes a lid on the top surface of the plurality of posts using an adhesive layer between the lid and the posts (as shown in Figure 1A). For some embodiments, the process flow may also dispose a TIM layer above a top surface of each die (as shown in Figure 1A) between steps 810 and 815. For other embodiments, the process flow may also dispose one or more other components (e.g., DSCs) on the substrate (as shown in Figure 7B).

Note that the semiconductor package formed by process flow 800 may include fewer or additional packaging components based on the desired packaging design (e.g. , as shown in Figures 1 - 7).

Figures 9 - 14 illustrate embodiments with integrated heat spreader customization using high throughput additive manufacturing for enhanced package thermomechanics. According to these embodiments, a semiconductor package may implement high throughput additive manufacturing to create custom features on a main, universal lid (e.g. , lid 102 of Figure 1A, lid 202 of Figure 2A, etc.). Accordingly, a universal lid may be designed and manufactured in large volumes using standard processes (e.g. , stamping) thus keeping the manufacturing cost low. Customizing the universal design for different packages and products can then be carried out during a final, high throughput additive manufacturing step that can be run as part of the assembly process. This step allows the simultaneous deposition and patterning of different features (e.g. , one or more protrusions and/or legs as shown in Figures 9 - 13), which can provide the thermomechanical characteristics needed to prevent (or hinder) thermal and reliability issues, while allowing the universal lid to be shared across multiple packages and technologies. Note that these embodiments, as described herein, also allow greater flexibility in terms of material choices and patterns (as described in detail above).

Figure 9 is a cross-sectional view of a semiconductor package 900 having a lid 902, one or more dies 905-906, a high throughput additively manufactured (HTAM) layer 910, and a substrate 901, according to one embodiment. Note that the semiconductor package 900 of Figure 9 is similar to the semiconductor packages 100 of Figure 1A and 200 of Figure 2A, however the semiconductor package 900 has the HTAM layer 910 disposed on a bottom surface 902b of the lid 902.

As used herein, a "HTAM layer" refers to an additively manufactured layer directly disposed on a lid using a high throughput deposition process and without the use of any intermediate adhesive layer. For example, the HTAM layer(s) may be patterned (as described in further detail below) to form custom features (e.g. , protrusions and/or legs of varying sizes and shapes) on the lid to drastically reduce (or prevent) thermal, mechanical, and reliability issues, usually associated with MCPs. The HTAM layer may include one or more different materials, such as metals, metal alloys, metal/ceramic composites, polymers, polymer-metal composites (e.g. , metal -filled resins), polymer-ceramic composites, epoxies, and/or any combination thereof. The HTAM layer's material properties (e.g., thermal conductivity, Young's modulus, coefficient of thermal expansion, or other properties) may be chosen or engineered to optimize the thermal and/or mechanical performance of the package.

As used herein, a "HTAM leg" refers to a portion of the HTAM layer that is disposed on one or more regions of the lid that do not fall within the die shadow (after the lid is assembled to the substrate containing the die or dies). For example, legs of varying sizes and shapes may be formed on the lid using a high throughout additive manufacturing process and are later mechanically coupled to regions on the substrate that do not contain die. The HTAM legs may also be implemented to address package thermomechanical issues.

The HTAM layers and legs can be formed through multiple methods, such as thermal spray, cold spray, dispensing, printing, etc. Note that for one embodiment each of the HTAM layers and HTAM legs is formed with a high throughput process/approach, however each of the HTAM layers and legs may also be formed with a non-high throughput approach based on an alternative embodiment (also note that this alternative embodiment is applicable to any other component described herein where that embodiment of the component(s) is formed with the high throughput process/approach). For example, when using cold spray to form the HTAM legs and layers, powders of the material to be deposited are accelerated through a nozzle at high speeds, forming a mechanical bond upon impact with the lid - without any adhesive layer. Patterning can be achieved by controlling the nozzle dimensions and movement, and/or by spraying the powders through a shadow mask containing the desired features. This approach allows flexibility in material choice since multiple material powders can be combined and used to create features with the desired thermal and mechanical properties. For most embodiments, this approach also allows the formation of the layers, legs, protrusions, etc., to be characterized as having a high throughput, realizing, for example, deposition rates around 50-100 um/sec in the thickness direction (depending on desired feature size and shape).

Referring now to Figure 9, the semiconductor package 900 includes the HTAM layer 910 disposed on a bottom surface 902b of the lid 902, where the lid 902 has a top surface 902a and a bottom surface 902b. The lid 902 may be a flat lid with legs 902c-d on the outer periphery (or edges) of the lid 902. For one embodiment, the HTAM layer 910 has a top surface 910a and a bottom surface 910b. The semiconductor package 900 further includes dies 905-906 disposed on the top surface 901a of the substrate 901 , where the die 905 has a larger z-height than the die 906. The lid 902 and the HTAM layer 910 disposed on the bottom surface 902b of the lid 902 may then be disposed above the dies 905-906 on the substrate 901 , attaching the legs 902c-d of the lid 902 to the substrate 901 with a sealant 925.

The present embodiments, as illustrated in Figure 9, address the issue of varying die heights in a MCP by depositing (or disposing) the HTAM layer 910 on the bottom surface 902b

of the lid 902 within the die shadow of die 906. This way, the TIM 930 above die 906 can be kept thin as the z-height mismatch between dies 905 and 906 is accommodated by the HTAM layer 910 (which can be deposited using metals or certain ceramics, achieving a thermal conductivity that can be 1-2 orders of magnitude higher than that of the TIM 930). This HTAM layer 910, therefore, maintains a reduced thermal resistance between the die 906 and the lid 902.

For one embodiment, the HTAM layer 910 may be formed as a large rectangle to match the die shadow of die 906. For other embodiments, the HTAM layer 910 is pattemed with one or more different shapes and sizes (e.g. , oval, square, picture frame, etc.) based on the desired package design. In addition, the lid 902 may be mechanically (and/or thermally) coupled to the substrate 901 with the sealant 925. The sealant 925 is formed between the top surface 901a of the substrate 901 and the bottom surfaces of the legs 902c-d.

For some embodiments, the TIMs 930 may be formed on the dies 905-906, coupling die 905 to the bottom surface 902b of the lid 902 and die 906 to the HTAM layer 910. For one embodiment, the BLT of the TIM 930 on die 905 may be equal or substantially equal to the BLT of TIM 930 on die 906, where the HTAM layer 920 accommodates for the varying z-heights of the dies 905-906. For another embodiment, the BLT of the TIM 930 on die 905 may be different from the BLT of TIM 930 on die 906.

Note that the semiconductor package 900 may include fewer or additional packaging components based on the desired packaging design.

Figure 10 is a cross-sectional view of a semiconductor package 1000 having a lid 1002, one or more dies 1005-1006, a HTAM leg 1010, and a substrate 1001 , according to one embodiment. Note that the semiconductor package 1000 of Figure 10 is similar to the semiconductor packages of Figures 1 -7 and 9, however the semiconductor package 1000 has the HTAM leg 1010 disposed on a bottom surface 1002b of the lid 1002.

Referring now to Figure 10, the semiconductor package 1000 includes the HTAM leg

1010 disposed on the bottom surface 1002b of the lid 1002, where the lid 1002 has a top surface 1002a and a bottom surface 1002b. The lid 1002 may be a flat lid with legs 1002c-d on the outer periphery of the lid 1002. For one embodiment, the HTAM leg 1010 has a top surface 1010a and a bottom surface 1010b. The semiconductor package 1000 further has dies 1005-1006 disposed on the top surface 1001 a of the substrate 1001, where the die 1005 has a larger z-height than the die 1006. For one embodiment, the dies 1005-1006 may be separated by the HTAM leg 1010 to reduce the maximum overhang between the edge of each die and the closest lid leg on the corresponding die side (for example, overhang "O" for the left side of die 1006 is shown in the figure). In addition, the lid 1002 and the HTAM leg 1010 disposed on the bottom surface 1002b of the lid 1002 may then be disposed above the dies 1005-1006 on the substrate 1001 , attaching the legs 1002c-d of the lid 1002 and the bottom surface 1010b of the HTAM leg 1010 to the substrate 1001 with a sealant 1025.

The present embodiment, as illustrated in Figure 10, addresses the issue of TIM stresses and delamination at the die edges due to large die overhang in the absence of the HTAM leg 1010. However, once the HTAM leg 1010 (or post) is formed on the bottom surface 1002b of the lid, the overhang ("O") can be greatly reduced for different package configurations (e.g. , semiconductor package 1000) by using the same lid (e.g., lid 1002), and varying the locations of the additively manufactured legs (e.g. , HTAM leg 1010) depending on the locations of the dies in each package configuration. For one embodiment, the HTAM leg 1010 has a straight rectangular shape. For other embodiments, the HTAM leg 1010 may also include other different shapes and sizes, such as an L-shape, T-shape, H-shape, picture frame, round pillars, etc., and/or any combination therein (e.g. , as shown in Figure 11).

For most embodiments, the lid 1002 may be mechanically (and/or thermally) coupled to the substrate 1001 with the sealant 1025. The sealant 1025 may be formed between the top surface 1001a of the substrate 1001 and the bottom surfaces of the legs 1002c-d and the HTAM leg 1010.

For some embodiments, the TIMs 1030 may be formed on the dies 1005-1006, coupling the dies 1005-1006 to the bottom surface 1002b of the lid 1002. For one embodiment, the BLT of the TIM 1030 on die 1005 may be equal or substantially equal to the BLT of TIM 1030 on die 1006, where for example a HTAM layer (not shown) may be formed to accommodate for the varying z-heights of the dies 1005-1006. For another embodiment, the BLT of the TIM 1030 on die 1005 may be different from the BLT of the TIM 1030 on die 1006, as shown in Figure 10.

Note that the semiconductor package 1000 may include fewer or additional packaging components based on the desired packaging design.

Figure 11 is a plan view of a bottom surface 1102b of a lid 1102 with one or more

HTAM legs 11 lOa-c, and showing one or more die shadows 1115-1119 according to one embodiment. Note that the lid of Figure 11 is similar to the lids used with the semiconductor packages as illustrated in Figures 1-7 and 9-10.

Referring now to Figure 11, the lid 1102 has one or more HTAM legs 11 lOa-c disposed on the bottom surface 1102b of the lid 1102. For some embodiments, the HTAM legs 11 lOa-c may have one or more different shapes that may be used for different packages to optimize each package's thermomechanical performance (e.g. , reducing a package's TIM stresses and preventing delamination). For example, the HTAM legs 11 lOa-c may include four L-shaped comer HTAM legs 1110a, four round pillar HTAM legs 1110b, and a picture frame HTAM leg 1110c. For most embodiments, the HTAM legs 11 lOa-c may be adjacent to or may surround one

or more of the die shadow regions 1115-1119. Note that a die shadow refers to a region on the bottom surface of a lid that occupies the same xy location as one of the dies on the substrate, once the lid is assembled to the substrate.

For most embodiments, the HTAM legs 11 lOa-c may be formed using AM methods, such as cold spray. For example, the patterning of the HTAM legs 11 lOa-c can be achieved by controlling the nozzle dimensions and movement, and/or by spraying the one or more powder materials through a shadow mask (not shown) to form the respective shapes (or any other desired shapes) directly on the bottom surface 1102b of the lid 1102.

Note that the lid 1102 may include fewer or additional packaging components based on the desired packaging design.

Figure 12 is a cross-sectional view of a semiconductor package 1200 having a lid 1202, one or more dies 1205-1206, one or more HTAM layers 1210, and a substrate 1201, according to one embodiment. Note that the semiconductor package 1200 of Figure 12 is similar to the semiconductor packages of Figures 1-7 and 9-10, however the semiconductor package 1200 has HTAM layers 1210 disposed on bottom surfaces 1202b of the lid 1202 and above each of the dies 1205-1206. Also note that having these HTAM layers 1210 on a lid 1202 with a thin top (shown as having thickness "A") helps to maintain the heat spreading from each die 1205-1206 through the lid while reducing the thermal cross-talk between the dies 1205-1206.

Referring now to Figure 12, the semiconductor package 1200 includes the HTAM layers 1210 disposed directly on the bottom surfaces 1202b (i.e., the die shadow regions) of the lid 1202. The lid 1202 may be a flat lid with the thin top (having thickness "A") and legs 1202c-d on the outer periphery of the lid 1202. The semiconductor package 1200 further includes dies 1205-1206 disposed on the top surface 1201a of the substrate 1201, where the die 1205 has a larger z-height than the die 1206. The lid 1202 and the HTAM layers 1210 disposed on the lid 1202 may then be disposed above the dies 1205-1206 on the substrate 1201, attaching the legs 1202c-d of the lid 1202 to the substrate 1201 with a sealant 1225.

The present embodiments, as illustrated in Figure 12, address the issue of thermal crosstalk between dies 1205-1206 by implementing a lid 1202 with a very thin top (having thickness "A" as shown) and by depositing the HTAM layers 1210 only in the die shadow locations on the lid (with respect to dies 1205-1206). This way, heat spreading from each die 1205-1206 through the lid is maintained, for example, by using one or more high-thermal conductivity materials for the HTAM layers 1210. In addition, the thermal cross-talk between the two dies 1205-1206, which is proportional to the cross-sectional area or thickness "A" of the lid, is reduced.

For one embodiment, the HTAM layers 1210 may be formed as large rectangles to match the die shadows of dies 1205-1206. For other embodiments, the HTAM layers 1210 may be

patterned with one or more different shapes and sizes based on the desired package design. In addition, the lid 1202 may be mechanically (and/or thermally) coupled to the substrate 1201 with the sealant 1225. The sealant 1225 is formed between the top surface 1201a of the substrate 1201 and the bottom surfaces of the legs 1202c-d.

For some embodiments, the TIMs 1230 may be formed on the dies 1205-1206, coupling dies 1205-1206 to the HTAM layers 1210 on the lid 1202. For one embodiment, the BLT of the TIM 1230 on die 1205 may be different from the BLT of the TIM 1230 on die 1206 based on the varying z-heights of dies 1205-1206 and the thicknesses of HTAM layers 1210. For other embodiments, the BLT of the TIM 1230 on die 1205 may be similar or equal to the BLT of the TIM 1230 on die 1206, for example, by choosing different thicknesses of the HTAM layers 1210 to accommodate for the varying z-heights of the dies 1205-1206.

Note that the semiconductor package 1200 may include fewer or additional packaging components based on the desired packaging design.

Figure 13 is a cross-sectional view of a semiconductor package 1300 having a lid 1302, one or more dies 1305-1306, one or more HTAM legs 1310, and a substrate 1301, according to one embodiment. Note that the semiconductor package 1300 of Figure 13 is similar to the semiconductor packages of Figures 1-7, 9-10, and 12, however the semiconductor package 1300 has HTAM legs 1310 disposed directly on the edges of the lid 1302, thus replacing the built-in (e.g., stamped) lid legs (e.g. , legs 1202c-d of Figure 12) with the HTAM legs 1310. Also note that having these HTAM legs 1310 additively manufactured onto the periphery of a universal, flat lid 1302 helps to simplify the packaging process and further reduce the manufacturing cost.

Referring now to Figure 13, the semiconductor package 1300 includes the HTAM legs 1310 disposed directly on the bottom surface 1302b of the lid 1302. The lid 1302 may be a flat lid top with no built-in (e.g., stamped) legs. Instead of having built-in legs, HTAM legs 1310 are disposed on the outer periphery of the lid 1302. The semiconductor package 1300 further includes dies 1305-1306 disposed on the top surface 1301a of the substrate 1301, where the die 1305 has a larger z-height than the die 1306. The lid 1302 with the HTAM legs 1310 may then be disposed above the dies 1305-1306 on the substrate 1301, attaching the HTAM legs 1310 disposed on the lid 1302 to the substrate 1301 with a sealant 1325.

For one embodiment, the HTAM legs 1310 may be formed as large rectangles. For other embodiments, the HTAM legs 1310 may be patterned with one or more different shapes and sizes based on the desired package design, such as HTAM legs formed as round pillars, a picture frame, etc. In addition, the lid 1302 may be mechanically (and/or thermally) coupled to the substrate 1301 with the sealant 1325. The sealant 1325 is formed between the top surface 1301a of the substrate 1301 and the bottom surfaces of the HTAM legs 1310.

For some embodiments, the BLT of the TIM 1330 on die 1305 may be different from the BLT of the TIM 1330 on die 1306 to accommodate for the varying z-heights of the dies 1305-1306. For other embodiments, a HTAM layer (similar to layer 1210 shown in Figure 12) can be formed on the lid in one or more of the die shadow regions to accommodate for the varying z-heights of the dies. For some of those other embodiments (e.g. using a HTAM layer in the die shadow regions), the BLT of the TIM 1330 on die 1305 may be equal or substantially equal to the BLT of TIM 1330 on die 1306.

Note that the semiconductor package 1300 may include fewer or additional packaging components based on the desired packaging design. For example, these embodiments may include any combinations of the above embodiments to address one or more thermal issues, including forming a lid with inner HTAM legs (and/or posts) and a pedestal in the thin die shadow region to reduce both die overhang and thin die junction to lid thermal resistance, etc.

Figure 14 is a process flow 1400 illustrating a method of forming a semiconductor package having a lid, one or more dies, one or more HTAM layers, and a substrate, according to one embodiment. Process flow 1400 illustrates a method of forming the semiconductor package. For example, process flow 1400 shows a method of forming a semiconductor package as shown in Figures 9 - 13, using for example AM processes such as cold spray.

At block 1405, the process flow 1400 disposes one or more dies on a substrate (as shown in Figure 9). At block 1410, the process flow 1400 disposes one or more HTAM layers on a bottom surface of a lid, wherein at least one of the HTAM layers is disposed on a die shadow region of the lid that corresponds to the xy location occupied by (or that is coplanar to) at least one of the dies on the substrate (as shown in Figure 9). For another embodiment, the process flow may dispose the HTAM layers on die shadow regions of the lid that correspond to each of the one or more dies on the substrate (as shown in Figure 12, i.e. , one HTAM layer for each die shadow region). For another embodiment, the process flow may dispose HTAM legs as part of the HTAM layer on a bottom surface of the lid in regions that are not within the die shadows. At block 1415, the process flow 1400 then disposes the lid with one or more legs, at least one HTAM layer or leg, a top surface, and a bottom surface that is opposite from the top surface on the substrate, wherein the one or more legs of the lid are attached to the substrate with a sealant (as shown in Figure 9). For some embodiments, the process flow may also dispose one or more TIM layers above a top surface of each of the one or more dies (as shown in Figures 9, 10, and 12-13).

Note that the semiconductor package formed by process flow 1400 may include fewer or additional packaging components based on the desired packaging design.

Figures 15 - 19 illustrate embodiments of semiconductor packages using a highly -

conductive (HC), intermediate layer deposited on a die by implementing a high-throughput additive deposition prior to dispensing a TIM layer. As used herein, a "HC intermediate layer" refers to a layer having a high thermal conductivity and formed with an AM method.

Figures 15-19 illustrate embodiments that use STIM and other novel or non-standard TIMs to improve the overall performance of the package as compared to using a typical PTIM, while also eliminating the need for traditional wafer-level BSM to enable wettability or special surface functionalization to improve adhesion. Note that for one embodiment each of the HC intermediate layers is formed with a highly conductive material (or implementation), however each of the HC intermediate layers may also be formed with a non-highly conductive material/implementation based on an alternative embodiment (also note that this alternative embodiment is applicable to any other component described herein where that embodiment of the component(s) is formed with the highly conductive implementation).

These embodiments (e.g. , as described in Figures 15-19) enhance packaging solutions by using a direct-write, high throughput additive deposition method that forms a highly conductive (HC) layer (also referred to as an intermediate layer, an additive deposition (AD) layer, or a HC intermediate layer) on a backside of a die at the wafer, die, or package level. This method, as described herein, is compatible with STIM and other novel or non-standard TIMs. For example, these embodiments enable the use of cold spray technology allowing the fast deposition of metals, metal alloys, and/or metal ceramic mixtures (or a combination thereof) directly on any semiconductor die (or components) at the wafer, die, or package level - without the need for

BSM, surface functionalization, or adhesion layers. In addition, these embodiments facilitate the formation of one or more HC layers at high deposition rates (e.g., layers that are few 100s of um thick can be deposited in roughly a few seconds). For some embodiments, the intermediate layers, as described herein, may be formed with 25-300 um thick layers that include one or more different metals and ceramics (e.g., copper (Cu), nickel (Ni), aluminum (Al), aluminum oxide (A1203)) directly disposed on a die (or any other packaging component) without any adhesion layers in between.

According to most embodiments, the additive deposition used to form a HC intermediate layer (e.g., the HC intermediate layer 1510 of Figure 15) has several significant advantages and unique capabilities compared to other typically used packaging solution/approaches (e.g. , plating or wafer-level sputtering to create BSM, etc.). In particular, several of the advantages of the present embodiments (e.g. , as shown in Figures 15-19) include: (i) a semiconductor package enabling the use of different TIMs such as solder TIM, high-metal filler epoxy TIMs, or sinterable pastes, all having good adhesion to the dies ; (ii) no requirement of wafer-level BSM; (iii) the intermediate layer (between die and TIM1) can be made from pure metals, metal alloys, and/or metal/ceramic composites, and its properties can be tailored for optimizing package thermals and mechanics (note that this flexibility in material selection is not available with other deposition methods such as electroplating which are limited to metals); (iv) a decreased deposition time compared to plating, sputtering, etc. (e.g., a 50 or 100 um metal layer can be produced in seconds or less using cold spray, but may take hours to plate); (v) the intermediate layer can be deposited at a wafer, die, or package level, and can thus be applied to any wafers as well as to any singulated dies or packages (e.g. , memory stacks); (vi) the intermediate layer can be deposited while keeping the die, package, or wafer at room temperature; (vii) the deposition conditions can be tailored to produce the intermediate layer with a rough surface, which can help improve adhesion to the TIM layer (e.g., metal-filled epoxy TIM or sintered paste) and increase surface area for heat transfer; and (viii) when patterned features (instead of a blanket coating) of the intermediate layer are desired, these embodiments can be easily implemented as part of the deposition method, given the nature of the AM processes being used, thus eliminating the need for multiple, expensive lithography steps (e.g. , resist deposition, exposure, development, resist removal, etc.) used in conjunction with other deposition approaches, such as plating.

Figure 15 is a cross-sectional view of a semiconductor package 1500 having a lid 1502, a die 1505, a HC intermediate layer 1510, a TIM layer 1530, and a substrate 1501, according to one embodiment. Note that the semiconductor package 1500 of Figure 15 is similar to the semiconductor packages of Figure 1-7 and 9-13, however the semiconductor package 1500 has the HC intermediate layer 1510 disposed between the TIM 1530 and the die 1505.

Referring now to Figure 15, the semiconductor package 1500 includes the HC intermediate layer 1510 disposed on a top surface 1505a of the die 1505. For one embodiment, the HC intermediate layer 1510 is disposed/formed between the top surface 1505a of the die 1505 and a bottom surface 1530b of TIM 1530. The semiconductor package 1500 further includes a lid 1502 (or an IHS) having a top surface 1502a and a bottom surface 1502b. For some embodiments, the lid 1502 may be a flat lid with legs 1502c-d on the outer periphery of the lid 1502. For one embodiment, the HC intermediate layer 1510 has a top surface 1510a and a bottom surface 1510b. For example, the top surface 1510a of the HC intermediate layer 1510 is directly attached to the bottom surface 1530b of the TIM 1530, while the bottom surface 1510b of the HC intermediate layer 1510 is directly attached to top surface 1505a of the die 1505 (note that no adhesion layer is formed in between these surfaces). The semiconductor package 1500 also has dies 1505 disposed on the top surface 1501a of the substrate 1501. The bottom surface 1502b of the lid 1502 may be disposed above the TIM 1530, the HC intermediate layer 1510, and the die 1505, respectively, on the substrate 1501, where the legs 1502c-d of the lid 1502 are attached to the substrate 1501 with a sealant 1525.

The present embodiments, as illustrated in Figure 15, show the HC intermediate layer 1510 that is additively deposited (AD) between the die 1505 and TIM 1530, for example, to widen the range of materials that can be used for TIM 1530. For example, the TIM 1530 may be formed using one or more different materials, such as polymer TIMs (which have good adhesion to dies but suffer from a relatively low effective thermal conductivity (2-5 W/m-K) compared to other TIMs), other TIMs (e.g., high metal filler epoxy, sintered paste, or solder TIM which may have higher thermal conductivities than polymer TIM but may not adhere as well to dies or may not wet the die surface altogether), and any other combination therein. This approach allows the HC intermediate layer 1510 to be formed using multiple different materials with an AM process and helps improve TIM adhesion as well as thermal and/or other thermomechanical properties of the overall package 1500.

For some embodiments, the semiconductor package 1500 implements high throughput AD method(s) to deposit/dispose the HC intermediate layer 1510 between the die 1505 and TIM 1530, enabling the use of a wide range of TIM materials including novel or non-standard TIMs. The HC intermediate layer 1510 can be made of metal, metal alloys, and/or metal/ceramic mixtures. The HC intermediate layer 1510 can also be used to enhance adhesion of the TIM 1530 (e.g. , epoxy TIM with metal filler) to the die 1505 or used to allow wettability of the backside of the die 1505 by the TIM 1530 (e.g., STIM). In addition, HC intermediate layer 1510 can also include one or more sublayers of multiple different materials deposited on top of each other (e.g. , a first layer is a metal, a second layer is a PTIM and stacked on the first layer, etc.).

For example, a HC intermediate layer (e.g., HC intermediate layer 1510) may be formed with a cold spray additive deposition of 25-300 urn thick metal or metal/ceramic layers directly on a die without any adhesion layer. In this example, the solid powders of the desired material or material mixtures (e.g. , metal and metal/ceramic particles) are deposited and then accelerated in a carrier gas jet (e.g. , compressed air) by passing the jet through a converging diverging nozzle. The jet exits the nozzle at a high velocity and is disposed on the die, where the impact causes the solid particles in the jet to plastically deform and bond to the die surface. Subsequent layers of the materials are similarly adhered to (or disposed on) each underlying layer upon continued jet impact, producing a fast buildup of layers (e.g. , layers that are few 100s of microns thick can be deposited in seconds or less). Moreover, unlike thermal spraying techniques, the cold spray additive deposition does not require melting the particles, enabling the die and/or substrate to remain at room temperature during the deposition of the HC materials.

For one embodiment, the HC intermediate layer 1510 may be formed as a large rectangle to match the die shadow of die 1505. For other embodiments, the HC intermediate layer 1510 is patterned with one or more different shapes and sizes (e.g., oval, square, picture frame, etc.)

based on the desired package design. As additive manufacturing is used, patterning to create one or more different shapes/features can be achieved as part of the deposition step by using a nozzle with a small exit diameter or a shadow mask for very small features. Note that this eliminates the need for using lithography and the additional steps associated with lithography, including subtractive or semi-additive methods, such as plating, sputtering, etc.

In addition, the lid 1502 may be mechanically (and/or thermally) coupled to the substrate 1501 with the sealant 1525. The sealant 1525 is formed between the top surface 1501a of the substrate 1501 and the bottom surfaces of the legs 1502c-d of the lid 1502.

For some embodiments, the TIM 1530 may be formed on the HC intermediate layer 1510, coupling the bottom surface 1502b of the lid 1502 and the top surface 1510a of the HC intermediate layer 1510.

Note that the semiconductor package 1500 may include fewer or additional packaging components based on the desired packaging design.

Figure 16A is a cross-sectional view of a semiconductor package 1600 (with the die and HC intermediate layers shown in top plan view in Figure 16B, and in a different configuration 1650 in Figure 16C) along the A - A' axis.

Referring now to Figure 16A, the semiconductor package 1600 has a lid 1602, a die 1605, one or more HC intermediate layers 1610-1611, one or more TIM layers 1630-1631, and a substrate 1601, according to one embodiment. Note that the semiconductor package 1600 of Figure 16 is similar to the semiconductor packages of Figure 1-7, 9-13, and 15, however the semiconductor package 1600 has a first HC intermediate layer 1610 disposed between a first TIM 1631 (e.g., a first TIM material, such as epoxy TIM with metal filler) and the die 1605, and a second HC intermediate layer 1611 disposed between a second TIM 1630 (e.g., a second TIM material, such as solder TIM) and the die 1605.

For one embodiment, the first HC intermediate layer 1610 and the second HC intermediate layer 1611 are both disposed on a top surface of the die 1505. For one embodiment, the first HC intermediate layer 1610 is disposed between the die 1605 and the first TIM 1631, while the second HC intermediate layer 1611 is disposed between the die 1605 and the second TIM 1630. Note that the first HC intermediate layer 1610 surrounds the second HC intermediate layer 1611, and the first TIM 1631 accordingly surrounds the second TIM 1630.

The semiconductor package 1600 further includes a lid 1602 having a top surface 1602a and a bottom surface 1602b. For some embodiments, the lid 1602 may be a flat lid with legs 1602c-d on the outer periphery of the lid 1602. For one embodiment, each of the HC

intermediate layers 1610-1611 has a top surface and a bottom surface. For example, the top surface of the first HC intermediate layer 1610 is directly attached to the bottom surface of the first TIM 1631, while the bottom surface of the first HC intermediate layer 1610 is directly attached to top surface 1605a of the die 1605 (note that no adhesion layer is formed in between these surfaces). Likewise, the top surface of the second HC intermediate layer 1611 is directly attached to the bottom surface of the second TIM 1630, while the bottom surface of the second HC intermediate layer 1611 is directly attached to top surface 1605a of the die 1605. The semiconductor package 1600 also has dies 1605 disposed on the top surface 1601a of the substrate 1601. The bottom surface 1602b of the lid 1602 may be disposed on and above the first and second TIMs 1630-1631. Accordingly, for some embodiments, the lid 1602 is disposed above the TIMs 1630-1631, the HC intermediate layers 1610-1611, and the die 1605, respectively, on the substrate 1601, where the legs 1602c-d of the lid 1602 are attached to the substrate 1601 with a sealant 1625.

The present embodiments, as illustrated in Figure 16A, enable one or more regions having different intermediate layers 1610-1611 and different TIM layers 1630-1631 with different materials. In addition, the present embodiments, as illustrated in Figures 16B and 16C, enable the HC intermediate layers 1630-1631 to be formed with one or more different patterns (e.g. , patches, strips, rings, picture frames, etc.). For example, as shown in Figure 16B of package 1600, the HC intermediate layers 1610-1611 may be formed as patches or strips of different intermediate layers, where the first HC intermediate layers 1610 are outer patches (or strips) and the second HC intermediate layer 1611 is an inner patch (or strip) surrounded by both the outer patches of the first HC intermediate layer 1610. Note that for this example, the TIMs 1631-1630 may respectively have the same patterns as the HC intermediate layers 1610-1611 (i.e. , TIM 1631 has two outer patches surrounding an inner patch of TIM 1630).

Alternatively, as shown in Figure 16C of package 1650 (which may be similar to package 1600 however with different intermediate and TIM layer patterns), the HC intermediate layers 1610-1611 may be formed in different configurations (e.g., a disk surrounded by a rectangular frame) of different intermediate layers, where the first HC intermediate layer 1610 is an outer rectangular frame with a circular hole in the middle, and the second HC intermediate layer 1611 is an inner disk that is surrounded by the outer rectangular frame of the first HC intermediate layer 1610. Note that for this example, the TIMs 1631-1630 may respectively have the same patterns as the HC intermediate layers 1610-1611 (i.e., TIM 1631 has an outer rectangular frame surrounding an inner disk of TIM 1630).

Accordingly and referring back to Figure 16A, the HC intermediate layers 1610-1611 may be applied on different die backside 1605a locations to allow the use of different TIMs 1630-1631 in the same semiconductor package 1600. This can be advantageous to co-optimize thermals, cost and reliability for semiconductor packages (e.g. , using a high-cost high

conductivity TIM only in the vicinity of hotspot areas, while using a less-expensive lower conductivity TIM in other locations, or using different TIMs for the die center and edge to reduce edge degradation during reliability testing). Also note that, when TIMs with different thicknesses are to be used, the heights of the different HC intermediate layers/regions can also be tailored so that the sum of the HC intermediate layer height and corresponding TIM layer height is the same for different regions.

In addition, the lid 1602 may be mechanically (and/or thermally) coupled to the substrate

1601 with the sealant 1625. The sealant 1625 is formed between the top surface 1601 a of the substrate 1601 and the bottom surfaces of the legs 1602c-d of the lid 1602.

For some embodiments, the first TIM 1631 may be disposed on the first HC intermediate layer 1610, coupling the bottom surface 1602b of the lid 1602 and the top surface of the first HC intermediate layer 1610. Likewise, for these embodiments, the second TIM 1630 may be disposed on the second HC intermediate layer 1611 , coupling the bottom surface 1602b of the lid

1602 and the top surface of the second HC intermediate layer 161 1.

Note that the semiconductor package 1600 may include fewer or additional packaging components based on the desired packaging design.

Figure 17 is a cross-sectional view of a semiconductor package 1700 having a lid 1702, one or more dies 1705-1706, a HC intermediate layer 1710, a TIM layer 1730, and a substrate 1701, according to one embodiment. Note that the semiconductor package 1700 of Figure 17 is similar to the semiconductor packages of Figure 1-7, 9-13, and 15-16, however the

semiconductor package 1700 is a MCP with dies 1705-1706 having different z-heights and HC intermediate layers 1710a-b having different z-heights to accommodate for the die z-height mismatch.

Referring now to Figure 17, the semiconductor package 1700 includes the HC intermediate layer 1710a disposed on die 1705 and the HC intermediate layer 1710b disposed on die 1706. For one embodiment, the HC intermediate layer 1710a is disposed between the die

1705 and the TIM 1730, while the HC intermediate layer 1710b is disposed between the die

1706 and the TIM 1730. The semiconductor package 1700 further includes a lid 1702 having a top surface 1702a and a bottom surface 1702b. For some embodiments, the lid 1702 may be a flat lid with legs 1702c-d on the outer periphery of the lid 1702.

In addition, the semiconductor package 1700 also has dies 1705-1706 disposed on the top surface 1701 a of the substrate 1701 , where the z-height of die 1705 is smaller than the z-height of die 1706. To accommodate for the die z-height mismatch, the semiconductor package forms the HC intermediate layer 1710a to have a z-height which is greater than a z-height of the HC intermediate layer 1710b.

For one embodiment, the top surface of the HC intermediate layer 1710a is directly attached to the bottom surface of the TIM 1730, while the bottom surface of the HC intermediate layer 1710a is directly attached to the top surface of the die 1705. Likewise, the top surface the HC intermediate layer 1710b is directly attached to the bottom surface of the TIM 1730, while the bottom surface of the HC intermediate layer 1710b is directly attached to the top surface of the die 1706. The bottom surface 1702b of the lid 1702 may be disposed above the TIMs 1730, the HC intermediate layer 1710a-b, and the die 1705-1706, respectively, on the substrate 1701, where the legs 1702c-d of the lid 1702 are attached to the substrate 1701 with a sealant 1725.

The present embodiments, as illustrated in Figure 17, facilitate MCPs (e.g. ,

semiconductor package 1700) with one or more dies 1705-1706 placed adjacent to each other on the substrate 1701. In particular, this can be advantageous as dies 1705-1706 have different z-heights. For example, rather than accommodating the z-height difference using additional TIM, the HC intermediate layers 1710a and 1710b can be deposited with different thicknesses (or z-heights) on the dies 1705-1706, respectively, to create a level surface over which the TIM layer 1730 (or a thin, uniform TIM) can be applied. Additionally, this can be advantageous as the HC intermediate layers 1710a-b can have thermal conductivity remarkably higher than that of the TIM 1730, as such any thick region needed to accommodate for the z-height differences between the dies 1705-1706 would have a lower thermal resistance when constructed using the AD materials of the HC intermediate layers 1710a-b rather than the materials of TIM 1730.

For one embodiment, the HC intermediate layers 1710a-b may be formed as large rectangles to match the die shadows of dies 1705-1706. For other embodiments, the HC intermediate layers 1710a-b can be patterned with one or more different shapes and sizes (as shown in Figures 16B and 16C) based on the desired package design. In addition, the lid 1702 may be mechanically (and/or thermally) coupled to the substrate 1701 with the sealant 1725. The sealant 1725 is formed between the top surface 1701a of the substrate 1701 and the bottom surfaces of the legs 1702c-d of the lid 1702.

For some embodiments, the TIM 1730 may be formed on the HC intermediate layers 1710a-b, coupling the bottom surface 1702b of the lid 1702 to the top surfaces of the HC intermediate layers 1710a and 1710b. For one embodiment, the BLT of the TIM 1730 above HC layer 1710a is similar or equal to the BLT of the TIM 1730 above HC layer 1710b. For other embodiments, the BLTs of the TIMs 1730 above HC layers 1710a and 1710b may be different.

Note that the semiconductor package 1700 may include fewer or additional packaging components based on the desired packaging design.

Figure 18 is a cross-sectional view of a semiconductor package 1800 having a lid 1802, one or more stacked dies 1805-1806, a HC intermediate layer 1810, a TIM layer 1830, and a

substrate 1801, according to one embodiment. Note that the semiconductor package 1800 of Figure 18 is similar to the semiconductor packages of Figure 1 -7, 9-13, and 15-17, however the semiconductor package 1800 is a MCP with dies 1805-1806 having different z-heights and vertically stacked, where the die 1806 is thus embedded in the HC intermediate layer 1810.

Referring now to Figure 18, the semiconductor package 1800 has die 1805 disposed on the top surface 1801a of the substrate 1801 and die 1806 is vertically stacked (or disposed on) the top surface of the die 1805. For some embodiments, the dies 1805-1806 may have similar or different z-heights. In addition, the semiconductor package 1800 includes the HC intermediate layer 1810 disposed over and around die 1806, while the HC intermediate layer 1810 is disposed on the exposed top surface of die 1805. For one embodiment, the HC intermediate layer 1810 is disposed between the stacked dies 1805-1806 and the TIM 1830. The semiconductor package 1700 further includes a lid 1802 having a top surface 1802a and a bottom surface 1802b. For some embodiments, the lid 1802 may be a flat lid with legs 1802c-d on the outer periphery of the lid 1702.

For one embodiment, the top surface of the HC intermediate layer 1810 is directly attached to the bottom surface of the TIM 1830, while the bottom surface of the HC intermediate layer 1810 is directly attached to the entire top surface of die 1806 and the exposed top surface of die 1805. The bottom surface 1802b of the lid 1802 may be disposed above the TIM 1830, the HC intermediate layer 1810, and the stacked dies 1805-1806, respectively, on the substrate 1801, where the legs 1802c-d of the lid 1802 are attached to the substrate 1801 with a sealant 1825.

For one embodiment, the HC intermediate layer 1810 may be deposited/patterned as a large rectangular enclosure (or lid) to match the die shadows of stacked dies 1805-1806. For other embodiments, the HC intermediate layer 1810 can be patterned with one or more different shapes and sizes (as shown in Figures 16B and 16C) based on the desired package design. In addition, the lid 1802 may be mechanically (and/or thermally) coupled to the substrate 1801 with the sealant 1825. The sealant 1825 is formed between the top surface 1801 a of the substrate 1801 and the bottom surfaces of the legs 1802c-d of the lid 1802.

For some embodiments, the TIM 1830 may be formed on the HC intermediate layer 1810, coupling the bottom surface 1802b of the lid 1802 and the top surface of the HC intermediate layer 1810.

Note that the semiconductor package 1800 may include fewer or additional packaging components based on the desired packaging design.

Figure 19 is a process flow illustrating a method of forming a semiconductor package having a lid, one or more dies, one or more HC intermediate layers, one or more TIM layers, and a substrate, according to one embodiment. Process flow 1900 illustrates a method of forming the semiconductor package. For example, process flow 1900 shows a method of forming a semiconductor package as shown in Figures 15 - 18, using for example AM processes such as cold spray.

At block 1905, the process flow 1900 disposes one or more dies on a substrate (as shown in Figures 15-18). At block 1910, the process flow 1900 disposes one or more highly-conductive (HC) intermediate layers on the one or more dies on the substrate (as shown in Figures 15-18). At block 1915, the process flow 1900 then disposes a lid with one or more legs on an outer periphery of the lid, a top surface, and a bottom surface that is opposite from the top surface on the substrate, wherein the one or more legs of the lid are attached to the substrate with a sealant, wherein the bottom surface of the lid is disposed over the one or more HC intermediate layers and the one or more dies on the substrate (as shown in Figures 15-18). For some embodiments, the process flow may also dispose one or more TIM layers above the one or more HC intermediate layers (as shown in Figures 15-18).

Note that the semiconductor package formed by process flow 1900 may include fewer or additional packaging components based on the desired packaging design.

Figures 20 - 26 illustrate embodiments of semiconductor packages with warpage mitigation structures, such as stiffeners, directly disposed on a substrate using high throughput additive manufacturing (e.g., as described in detail above). As used herein, a "stiffener" (also referred to as a warpage mitigation structure or stiffener structure) refers to using one or more materials to dispose a stiffening structure directly on a top surface of a substrate or a die for mitigating warpage. Further, the stiffener may be formed using one or more different materials, such as metals (e.g. , copper (Cu), aluminum (AI), titanium (Ti), nickel (Ni), etc.), metal alloys (e.g. , stainless steel), metal/ceramic composites (e.g., Cu/diamond, Cu/alumina, etc.), and/or any combination thereof. As used herein, the stiffener (e.g., as shown in Figures 20 - 24) may be formed directly on the substrate (and/or the die) to reduce warpage using high throughput AM processes, such as cold spray, that facilitate the simultaneous deposition and patterning of various materials directly on the substrate (and/or the die) at a fast deposition rate. These stiffeners, as described herein, may be integrated with, and manufactured onto the substrate at panel or unit level. In addition, the geometries/shapes and materials of these stiffeners may be customized for each package to enable the necessary stiffness to mitigate warpage (e.g. , as shown in Figures 22A and 22B).

According to most embodiments, disposing the stiffeners directly on the substrate (and/or the die) using AM has several significant advantages and unique capabilities compared to other typically used packaging solution/approaches (e.g. , one-piece discrete stiffeners, semi-additive manufacturing of stiffeners, etc.). In particular, several of the advantages of the present

embodiments (e.g. , as shown in Figures 20-25) include: (i) the need for handling and assembling discrete stiffeners is eliminated; (ii) the stiffeners are disposed directly on the substrate (and/or the die) without using an adhesive layer (e.g., an epoxy layer) in between substrate and stiffeners, thereby strengthening the mechanical coupling between the substrate and stiffener and improving warpage mitigation; (iii) a wide range of materials can be used for optimizing the mechanical properties of the stiffener structures to minimize warpage (e.g. , metals (Ni, Cu, etc.), metal alloys (stainless steel), metal/ceramic composites (Cu and alumina mixture, Cu and diamond, etc.), polymers, and any combinations thereof). Note that many of these materials and combinations cannot be electroplated or implemented to form discrete stiffeners, but can be implemented using AM methods, such as cold spray. Also note that these materials can be engineered so that their mechanical properties are optimized for warpage or stress reduction by controlling the fractions of the constituent elements, which cannot be done when using pure (bulk) materials); (iv) AM enables simultaneous deposition and patterning of the stiffener in one step, thereby allowing the design to be optimized for size and stiffness without the constraint of needing a "one-piece" design to facilitate the stiffener assembly to the package (thereby saving, for example, more real estate of the substrate to be available for other components or allowing further miniaturization of the package); (v) the stiffeners can be deposited to have rough surfaces (e.g. , 10 um surface roughness) to enhance the adhesion to other materials in subsequent packaging steps, such as molding (e.g., as shown in Figure 24); and (vi) the stiffeners reduce the assembly process time and the cost by bypassing the additional steps and costs associated with using semi-additive deposition processes (e.g seed layer deposition, lithography, plating, seed layer removal, etc.).

Figure 20 is a cross-sectional view of a semiconductor package 2000 having a die 2005, a plurality of stiffeners 2010, and a substrate 2001, according to one embodiment. Note that the semiconductor package 2000 of Figure 20 may be similar to the semiconductor packages of Figures 1-19; however the semiconductor package 2000 does not include a lid (or IHS) and, more specifically, has stiffeners 2010 disposed directly on a top surface 2001a of the substrate 2001.

Referring now to Figure 20, the semiconductor package 2000 includes the substrate 2001 having a die 2005 disposed on the substrate 2001, wherein each die 2005 has a bottom surface that is electrically coupled to the substrate 2001 and a top surface that is opposite from the bottom surface. For one embodiment, the die 2005 is electrically coupled to the substrate 2001 with a plurality of solder balls 2045. The semiconductor package 2000 further includes stiffeners 2010 disposed directly on the top surface 2001a of the substrate 2000. For most embodiments, the stiffeners 2010 are directly attached to (or disposed on) the top surface 2001a of the substrate 2001 without an adhesive layer.

For some embodiments, the direct deposition of the stiffeners 2010 onto the substrate 2001 can be applied at a panel level or a unit level. For example, the stiffeners 2010 can be deposited on a top organic layer of the substrate 2001 (e.g., on a solder resist layer) or a top metal layer of the substrate 2001 (e.g. , on a Cu layer that is exposed after the solder resist removal). According to most embodiments, the plurality of stiffeners 2010 can include one or more stiffeners having different shapes and/or heights. In addition, the stiffeners 2010 can include one or more different materials/compositions, such as metals (e.g., Cu, Ni, Al), metal/ceramic composites (e.g., Cu/ Alumina), metal alloys (e.g., stainless steel), polymers, and/or any combinations thereof. Note that the material formulations of the stiffeners 2010 can be controlled/selected to optimize the mechanical properties needed to mitigate the warpage of the semiconductor package 2000 by, for example, controlling the fractions of the individual components of each material.

Also note that the semiconductor package 2000 may include fewer or additional packaging components based on the desired packaging design.

Figure 21 is a cross-sectional view of a semiconductor package 2100 having one or more dies 2105-2106, a plurality of stiffeners 2110, and a substrate 2101, according to one embodiment. Note that the semiconductor package 2100 of Figure 21 is similar to the semiconductor package 2000 of Figures 20, however the semiconductor package 2100 is a MCP that has two or more dies 2105-2106 disposed on a top surface 2101a of the substrate 2101.

Referring now to Figure 21, the semiconductor package 2100 includes the substrate 2101 having the dies 2105-2106 disposed on the substrate 2101, wherein each of the dies 2105-2106 has a bottom surface that is electrically coupled to the substrate 2101 and a top surface that is opposite from the bottom surface. For one embodiment, each of the dies 2105-2106 is electrically coupled to the substrate 2101 with a plurality of solder balls 2145. The

semiconductor package 2100 further includes stiffeners 2110 disposed directly on the top surface 2101a of the substrate 2100. For most embodiments, the stiffeners 2110 are directly attached to (or disposed on) the top surface 2101a of the substrate 2101 without an adhesive layer.

Also note that the semiconductor package 2100 may include fewer or additional packaging components based on the desired packaging design.

Figures 22 A and 22B are plan views of semiconductor packages 2200 and 2250, respectively. Note that the semiconductor packages 2200 and 2250 of Figures 22A and 22B are similar to the semiconductor packages 2000 and 2100 of Figures 20 and 21, however these semiconductor packages 2200 and 2250 illustrate two different designs of MCPs with one or more stiffeners 2210a-c in package 2200 and stiffener 2210 in package 2250 having one or more different shapes.

Referring now to Figure 22A, a top view of the semiconductor package 2200 is shown. Figure 22 A illustrates the semiconductor package 2200 having one or more dies 2205-2207 disposed on a top surface 2201a of a substrate 2201. In addition, the semiconductor package 2200 also includes a plurality of stiffeners 2210a-c having one or more different shapes disposed directly on the top surface 2201a of the substrate, according to some embodiments. For some embodiments, the one or more dies 2205-2207 are surrounded with the plurality of stiffeners 2210a-c.

For one embodiment, as shown in Figure 22A, the stiffeners 2210a-c are formed with three different shapes: four L-shaped comer stiffeners 2210a are located on the outer periphery (or edges) of the substrate 2201 , two rectangular stiffeners 2210b are disposed on opposite edges of the substrate 2201 , and a large picture frame stiffener 2210c surrounds die 2205 on the substrate 2201. For other embodiments, the stiffeners 2210a-c may have other shapes and sizes such as square-shaped stiffeners, round pillar stiffeners, H-shaped stiffeners, T-shaped stiffeners, and/or any combination thereof. The stiffeners 2210a-c may have similar or different surface areas and/or z-heights, depending on the desired thermomechanical properties and/or package design.

Note that the semiconductor package 2200, as shown in Figure 22A, may include fewer or additional packaging components based on the desired packaging design.

Referring now to Figure 22B, a top view of the semiconductor package 2250 is shown.

Figure 22B illustrates the semiconductor package 2250 having one or more dies 2205-2206 disposed on the top surface 2201a of the substrate 2201. In addition, the semiconductor package 2250 also includes a stiffener 2210 having an H-shape disposed directly on the top surface 2201 a of the substrate, according to some embodiments. For some embodiments, the one or more dies 2205-2206 are surrounded with (and/or adjacent to) the stiffener 2210. For one embodiment, as shown in Figure 22B, the stiffener 2210 is formed with a large H-shaped stiffener shape that surrounds dies 2205-2206 and separates each of the dies 2205-2206 on the substrate 2201.

Note that the semiconductor package 2250, as shown in Figure 22B, may include fewer or additional packaging components based on the desired packaging design.

Figure 23 is a cross-sectional view of a semiconductor package 2300 having a die 2305, a plurality of stiffeners 2310a-c, and a substrate 2301, according to one embodiment. Note that the semiconductor package 2300 of Figure 23 is similar to the semiconductor packages of Figures 20-22, however the semiconductor package 2300 has one or more different stiffeners 2310a-c that are disposed directly on the substrate 2301, the die 2305, and both the substrate 2301 and the die 2305.

Referring now to Figure 23, the semiconductor package 2300 includes the substrate 2301 having the die 2305 disposed on the substrate 2301, wherein the die 2305 has a bottom surface that is electrically coupled to the substrate 2301 and a top surface that is opposite from the bottom surface. For one embodiment, the die 2305 is electrically coupled to the substrate 2301 with a plurality of solder balls 2345. According to some embodiments, the semiconductor package 2301 further includes stiffener 2310a disposed directly on the top surface 2301a of the substrate 2301, stiffener 2310b disposed directly on the top surface 2301a of the substrate 2301 and on a top surface 2305a of the die 2305, and stiffener 2310c disposed directly on the top surface 2305 a of the die 2305. Note that each of the stiff eners 2310a-c are directly disposed on their respective surfaces without an adhesive layer.

Also note that the semiconductor package 2300 may include fewer or additional packaging components based on the desired packaging design.

Figure 24 is a cross-sectional view of a semiconductor package 2400 having one or more dies 2405-2407, a plurality of stiffeners 2410a-b, a molding layer 2402 (or a mold layer), and a substrate 2401, according to one embodiment. Note that the semiconductor package 2400 of Figure 24 may be similar to the semiconductor packages of Figures 20-23, however the semiconductor package 2400 is a molded MCP with the mold layer 2402 formed over and around the die 2406 and the stacked dies 2405 and 2407. Also note that the interconnects between dies 2405 and 2407 and between die 2406 and substrate 2401 (e.g. , solder balls/bumps or wire bonds) have been omitted to maintain clarity and avoid confusion.

Referring now to Figure 24, the semiconductor package 2400 includes the substrate 2401 having the dies 2405-2406 disposed on the substrate 2401, wherein each of the dies 2405-2406 has a bottom surface that is electrically coupled to the substrate 2401 and a top surface that is opposite from the bottom surface. Furthermore, the semiconductor package 2400 also has die 2407 stacked on die 2405, where the die 2407 may be electrically coupled to at least one of the die 2405 and the substrate 2401. The semiconductor package 2400 further includes stiffeners 2410a disposed directly on the top surface 2401a of the substrate 2401, and stiffeners 2410b disposed directly on both the top surface 2401a of the substrate 2401 and the top surface of the die 2405. For one embodiment, the stiffener 2410b may be disposed on the outer periphery of the top surface of die 2405, while also surrounding the stacked die 2407. For most embodiments, the stiffeners 2410a-b are directly attached to (or disposed on) their respective surfaces without an adhesive layer.

For some embodiments, the semiconductor package 2400 includes the mold layer 2402 to be formed (or deposited) over and around the stiffeners 2410a-b and the dies 2405-2407. For example, using AD techniques like cold spray to form the stiffeners 2410a-b on the

semiconductor package 2400 has the advantage that the surfaces of the stiffeners 2410a-b can be made rough to enhance adhesion to the molding layer 2402 (or the molding compound) in the subsequent molding steps. As such, the stiffeners 2410a-b may have rough surfaces to enable strong adhesion to the molding layer 2402 and thus avoid any delamination and/or failure in the package 2400.

For one embodiment, the mold layer 2402 is deposited over and around the dies 2405-2407. In addition, after depositing the mold layer 2402, the mold layer 2402 may then be cured. The mold layer 2402 helps to protect dies 2405-2407 from humidity, corrosion, and other damage. The mold layer may also help further reduce the warpage of package 2400. According to other embodiments, a semiconductor package (e.g., semiconductor package 2400) may have more than one mold layer based on the stacked systems or dies that may have different encapsulation requirements. For one embodiment, the mold layer 2402 is made of an epoxy with one or more filler materials.

According to some embodiments, the mold layer 2402 may have an outer surface 2402a, where for example the top surface of the stiffeners 2410b are exposed. Note that, for other embodiments, the outer surface 2402a of the mold layer 2402 may be recessed to expose the top surface(s) of at least one of the dies 2406 and 2407 (i.e. , top surfaces 2406a and 2407a may be exposed based on the desired packaging design). For example, the mold layer 2402 may be recessed with a mold grinding/polishing process to provide a flat, polished surface on any of the exposed components (e.g. , stiffener 2410b and/or dies 2406-2407. In addition, the outer surface 2402a of the mold layer 2402 may also have a coating (not shown) that electrically isolates any of the electrical components in package 2400 from the external environment.

For one alternate embodiment, the stiffeners 2410b may be enlarged and/or connected and used to completely encapsulate both of the stacked dies 2407 and 2405 (i.e., rather than having the mold layer 2402 encapsulating die 2407). For another alternate embodiment, the top surface 2406a of die 2406 may be recessed and exposed to electrically couple and/or stack an additional die (not shown) onto the exposed top surface 2406a of die 2406.

For one embodiment, each of the dies 2405-2406 may be electrically coupled to the substrate 2401 via an underfill layer (not shown) which may also include first level interconnects (FLI), such as solder bumps. In addition, die 2407 may be electrically coupled to die 2405 and/or to substrate 2401 using one or more wire bonds (not shown).

Note that the semiconductor package 2400 may include fewer or additional packaging components based on the desired packaging design.

Figure 25 is a process flow 2500 illustrating a method of forming a semiconductor package having one or more dies, one or more stiffeners, and a substrate, according to one

embodiment. Process flow 2500 illustrates a method of forming the semiconductor package. For example, process flow 2500 shows a method of forming a semiconductor package as shown in Figures 20-24, using for example AM processes such as cold spray.

At block 2505, the process flow 2500 disposes one or more dies on a substrate, wherein each die has a bottom surface that is electrically coupled to the substrate and a top surface that is opposite from the bottom surface (as shown in Figures 20-24). At block 2510, the process flow 2500 disposes a plurality of stiffeners directly on the substrate (as shown in Figures 20-24).

For one embodiment, the process flow may have the plurality of stiffeners directly attached to a top surface of the substrate without an adhesive layer (as shown in Figures 20-24). For some embodiments, the process flow may have the plurality of stiffeners having different sizes and/or shapes (e.g. , H-shaped, rectangular, picture-frame, round, etc., as shown in Figures 20-24). For some embodiments, the process flow may form a mold layer (or encapsulation layer) over the one or more dies, the plurality of stiffeners, and the substrate (as shown in Figure 24). For one embodiment, the process flow may have two or more dies stacked on each other (as shown in Figure 24). For other embodiments, the process flow may have the plurality of stiffeners disposed directly on a top surface of a die, on both the top surfaces of the die and a substrate, and/or on the top surface of the substrate (as shown in Figure 23).

Note that the semiconductor package formed by process flow 2500 may include fewer or additional packaging components based on the desired packaging design.

Figure 26 is a schematic block diagram illustrating a computer system that utilizes a device package that may include one or more dies, one or more stiffeners, a molding layer, and a substrate, as described herein. Figure 26 illustrates an example of computing device 2600.

Computing device 2600 houses motherboard 2602. Motherboard 2602 may include a number of components, including but not limited to processor 2604, device package 2610, and at least one communication chip 2606. Processor 2604 is physically and electrically coupled to motherboard 2602. For some embodiments, at least one communication chip 2606 is also physically and electrically coupled to motherboard 2602. For other embodiments, at least one communication chip 2606 is part of processor 2604.

Depending on its applications, computing device 2600 may include other components that may or may not be physically and electrically coupled to motherboard 2602. These other components include, but are not limited to, volatile memory (e.g., DRAM), non-volatile memory (e.g. , ROM), flash memory, a graphics processor, a digital signal processor, a crypto processor, a chipset, an antenna, a display, a touchscreen display, a touchscreen controller, a battery, an audio codec, a video codec, a power amplifier, a global positioning system (GPS) device, a compass, an accelerometer, a gyroscope, a speaker, a camera, and a mass storage device (such as hard disk drive, compact disk (CD), digital versatile disk (DVD), and so forth).

At least one communication chip 2606 enables wireless communications for the transfer of data to and from computing device 2600. The term "wireless" and its derivatives may be used to describe circuits, devices, systems, methods, techniques, communications channels, etc., that may communicate data through the use of modulated electromagnetic radiation through a non-solid medium. The term does not imply that the associated devices do not contain any wires, although in some embodiments they might not. At least one communication chip 2606 may implement any of a number of wireless standards or protocols, including but not limited to Wi-Fi (IEEE 802.11 family), WiMAX (IEEE 802.16 family), IEEE 802.20, long term evolution (LTE), Ev-DO, HSPA+, HSDPA+, HSUPA+, EDGE, GSM, GPRS, CDMA, TDMA, DECT, Bluetooth, derivatives thereof, as well as any other wireless protocols that are designated as 3G, 4G, 5G, and beyond. Computing device 2600 may include a plurality of communication chips 2606. For instance, a first communication chip 2606 may be dedicated to shorter range wireless communications such as Wi-Fi and Bluetooth and a second communication chip 2606 may be dedicated to longer range wireless communications such as GPS, EDGE, GPRS, CDMA, WiMAX, LTE, Ev-DO, and others.

Processor 2604 of computing device 2600 includes an integrated circuit die packaged within processor 2604. Device package 2610 may be, but is not limited to, a packaging substrate and/or a printed circuit board. Device package 2610 may include one or more dies, one or more stiffeners, a molding layer, and a substrate (as illustrated in Figures 20-25) - or any other components from the figures described herein - of the computing device 2600. Further, the device package 2610 may implement warpage mitigation structures, such as stiffeners, disposed directly on a substrate using high throughput additive manufacturing.

Note that device package 2610 may be a single component, a subset of components, and/or an entire system, as the AD materials, features, and components may be limited to device package 2610 and/or any other component that requires AD materials, features, and components.

For some embodiments, the integrated circuit die may be packaged with one or more devices on device package 2610 that include a thermally stable RFIC and antenna for use with wireless communications. The term "processor" may refer to any device or portion of a device that processes electronic data from registers and/or memory to transform that electronic data into other electronic data that may be stored in registers and/or memory.

At least one communication chip 2606 also includes an integrated circuit die packaged within the communication chip 2606. For some embodiments, the integrated circuit die of the communication chip may be packaged with one or more devices on the device package 2610, as described herein.

The following examples pertain to further embodiments. The various features of the different embodiments may be variously combined with some features included and others excluded to suit a variety of different applications.

For some embodiments, note that any of the embodiments described herein may be used in combination, such as a semiconductor package having a post and an AM layer on a die, a semiconductor package having a post and an intermediate layer, a semiconductor package having a post, an AM layer on die, AM legs on a lid, and an intermediate layer, and/or any combination of embodiments as described herein.

Example 1 is a device package, comprising a substrate having one or more dies disposed on the substrate, wherein each die has a bottom surface that is electrically coupled to the substrate and a top surface that is opposite from the bottom surface; and a plurality of stiffeners disposed directly on the substrate.

In example 2, the subject matter of example 1 can optionally include the plurality of stiffeners directly attached to a top surface of the substrate without an adhesive layer.

In example 3, the subject matter of any of examples 1 -2 can optionally include the plurality of stiffeners including one or more different sizes. The plurality of stiffeners further include one or more different shapes, including at least one of a rectangular stiffener, a picture frame stiffener, a L-shaped stiffener, a H-shaped stiffener, and a round pillar stiffener.

In example 4, the subject matter of any of examples 1 -3 can optionally include the plurality of stiffeners including one or more materials. The one or more materials include at least one or more of metals, metal alloys, metal-ceramic composites, polymers, polymer-metal composites, polymer-ceramic composites, epoxy, and ceramics.

In example 5, the subject matter of any of examples 1 -4 can optionally include the plurality of stiffeners disposed on the top surface of the substrate using a cold spray process.

In example 6, the subject matter of any of examples 1 -5 can optionally include a mold layer formed around and over the one or more dies, the plurality of stiffeners, and the top surface of the substrate.

In example 7, the subject matter of any of examples 1 -6 can optionally include at least one of the plurality of dies disposed on another of the dies on the substrate.

In example 8, the subject matter of any of examples 1 -7 can optionally include a plurality of solder balls electrically coupling the bottom surface of each die to the substrate.

In example 9, the subject matter of any of examples 1 -8 can optionally include the plurality of stiffeners further including a first set of stiffeners disposed directly on a top surface of a die, a second set of stiffeners disposed directly on both the top surface of the die and the top surface of the substrate, and a third set of stiffeners disposed directly on the top surface of the substrate. The first and second sets of stiffeners are disposed on the top surface of the die without an adhesive layer

In example 10, the subject matter of any of examples 1-9 can optionally include that the substrate is a printed circuit board.

Example 1 1 is a method of forming a device package, comprising disposing one or more dies on a substrate. Each die has a bottom surface that is electrically coupled to the substrate and a top surface that is opposite from the bottom surface; and disposing a plurality of stiffeners directly on the substrate.

In example 12, the subject matter of example 1 1 can optionally include the plurality of stiffeners directly attached to a top surface of the substrate without an adhesive layer.

In example 13, the subject matter of any of examples 11 -12 can optionally include the plurality of stiffeners including one or more different sizes. The plurality of stiffeners further include one or more different shapes, including at least one of a rectangular stiffener, a picture frame stiffener, a L-shaped stiffener, a H-shaped stiffener, and a round pillar stiffener.

In example 14, the subject matter of any of examples 11 -13 can optionally include the plurality of stiffeners including one or more materials. The one or more materials including at least one or more of metals, metal alloys, metal-ceramic composites, polymers, polymer-metal composites, polymer-ceramic composites, epoxy, and ceramics.

In example 15, the subject matter of any of examples 11 -14 can optionally include the plurality of stiffeners disposed on the top surface of the substrate using a cold spray process.

In example 16, the subject matter of any of examples 11 -15 can optionally include forming a mold layer around and over the one or more dies, the plurality of stiffeners, and the top surface of the substrate.

In example 17, the subject matter of any of examples 11 -16 can optionally include at least one of the plurality of dies is disposed on another of the dies on the substrate.

In example 18, the subject matter of any of examples 11 -17 can optionally include electrically coupling the bottom surface of each die to the substrate with a plurality of solder balls.

In example 19, the subject matter of any of examples 11 -18 can optionally include the plurality of stiffeners further including a first set of stiffeners disposed directly on a top surface of a die, a second set of stiffeners disposed directly on both the top surface of the die and the top surface of the substrate, and a third set of stiffeners disposed directly on the top surface of the substrate. The first and second sets of stiffeners are disposed on the top surface of the die without an adhesive layer.

Example 20 is device package comprising a substrate having one or more dies disposed

on the substrate. Each die has a bottom surface that is electrically coupled to the substrate and a top surface that is opposite from the bottom surface; a plurality of stiffeners disposed directly on the substrate; and a mold layer formed around and over the one or more dies, the plurality of stiffeners, and the substrate.

In example 21, the subject matter of example 20 can optionally include the plurality of stiffeners directly attached to a top surface of the substrate without an adhesive layer. The plurality of stiffeners are disposed on the top surface of the substrate using a cold spray process. The plurality of stiffeners include one or more different sizes. The plurality of stiffeners further includes one or more different shapes, including at least one of a rectangular stiffener, a picture frame stiffener, a L-shaped stiffener, a H-shaped stiffener, and a round pillar stiffener.

In example 22, the subject matter of any of examples 20-21 can optionally include the plurality of stiffeners including one or more materials. The one or more materials include at least one or more of metals, metal alloys, metal-ceramic composites, polymers, polymer-metal composites, polymer-ceramic composites, epoxy, and ceramics. At least one of the plurality of dies is disposed on another of the dies on the substrate.

In example 23, the subject matter of any of examples 20-22 can optionally include a plurality of solder balls electrically coupling the bottom surface of each die to the substrate.

In example 24, the subject matter of any of examples 20-23 can optionally include the plurality of stiffeners further includes a first set of stiffeners disposed directly on a top surface of a die, a second set of stiffeners disposed directly on both the top surface of the die and the top surface of the substrate, and a third set of stiffeners disposed directly on the top surface of the substrate. The first and second sets of stiffeners are disposed on the top surface of the die without an adhesive layer.

In the foregoing specification, embodiments have been described with reference to specific exemplary embodiments thereof. It will be evident that various modifications may be made thereto without departing from the broader spirit and scope. The specification and drawings are, accordingly, to be regarded in an illustrative sense rather than a restrictive sense.