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1. (WO2012125592) LOCALIZED DEPOSITION OF POLYMER FILM ON NANOCANTILEVER CHEMICAL VAPOR SENSORS BY SURFACE-INITIATED ATOM TRANSFER RADICAL POLYMERIZATION
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What is claimed is:

1. A cantilever chemical vapor sensor, comprising:

a cantilever structure having a base, having at least one leg extending from said base and having a tip at a distal end of said at least one leg, said cantilever structure attached to a substrate at said base thereof and configured to oscillate at a natural resonant frequency F0; a sorbent film attached to a location of said cantilever structure selected from the group of locations consisting of said base, said at least one leg and said tip, and absent from another of said locations of said cantilever structure selected from the group of locations consisting of said base, said at least one leg and said tip, said sorbent film configured to collect by sorbtion molecules from a vapor is contact with said cantilever structure, said molecules collected configured to cause a change AF in said natural resonant frequency F0; and

a signal output port configured to provide a signal representative of said oscillation frequency of said cantilever structure.

2. The cantilever chemical vapor sensor of claim 1, wherein a promoter film is situated on a surface of said cantilever structure at said location of said cantilever structure selected from the group of locations consisting of said base, said at least one leg and said tip where said sorbent film is attached.

3. The cantilever chemical vapor sensor of claim 2, wherein said promoter film is a layer of gold.

4. The cantilever chemical vapor sensor of claim 3, wherein a polymerization initiator is present on said layer of gold.

5. The cantilever chemical vapor sensor of claim 1, wherein said another of said locations of said cantilever structure selected from the group of locations consisting of said base, said at least one leg and said

location where a passivation layer is present.

6. The cantilever chemical vapor sensor of claim 1, wherein said passivation layer comprises chromium.

7. The cantilever chemical vapor sensor of claim 6, wherein said passivation layer comprises oxidized chromium having a self assembled monolayer deposited on said oxidized chromium.

8. The cantilever chemical vapor sensor of claim 1, further comprising a promoter film and a passivation layer, said promoter film applied to at least two of said locations of said cantilever structure selected from the group of locations consisting of said base, said at least one leg and said tip, and said passivation layer applied over said promoter layer at at least one of said locations of said cantilever structure selected from the group of locations consisting of said base, said at least one leg and said tip.

9. The cantilever chemical vapor sensor of claim 1, wherein said sorbent film is a polymer having a glass temperature Tg.

10. A method of fabricating a cantilever chemical vapor sensor, comprising the steps of:

defining on a surface of a substrate a plurality of regions to be fabricated into a cantilever structure, which cantilever structure when completed comprises a base, at least one leg extending from said base and a tip at a distal end of said at least one leg, and a signal output port configured to provide a signal representative of an oscillation frequency of said cantilever structure;

applying and patterning a promoter layer at one or more of said regions defined as said base, said at least one leg and said tip;

overcoating said promoter lay

said regions defined as said base, said at least one leg and said tip, while leaving a portion of said promoter layer uncoated; etching said substrate so as to fabricate said cantilever structure comprising said base, said at least one leg extending from said base, and said tip at a distal end of said at least one leg, said base of said cantilever structure remaining attached to said substrate and said signal output port; and

depositing a sorbing layer over said uncoated promoter layer while inhibiting said sorbing layer from depositing on said passivating layer; said cantilever structure configured to oscillate at a natural resonant frequency F0 in the absence of a sorbate on said sorbing layer and to oscillate at a frequency F0 + ΔF in the presence of a sorbate on said sorbing layer.

1 1. The method of fabricating a cantilever chemical vapor sensor of claim 10, wherein said promoter layer comprises gold.

12. The method of fabricating a cantilever chemical vapor sensor of claim 11, further comprising the step of overcoating said gold with a polymerization initiator prior to the step of depositing a sorbing layer over said uncoated promoter layer.

13. The method of fabricating a cantilever chemical vapor sensor of claim 10, wherein said passivating layer comprises chromium.

14. The method of fabricating a cantilever chemical vapor sensor of claim 13, further comprising the steps of oxidizing said chromium and growing a self assembled monolayer of an additional passivating layer on said oxidized chromium prior to the step of depositing a sorbing layer over said uncoated promoter layer.

15. The method of fabricating a cantilever chemical vapor sensor of claim 10, wherein said step of applying and patterning a promoter layer comprises the steps of: depositing a gold layer; and

patterning said gold layer.

16. The method of fabricating a cantilever chemical vapor sensor of claim 15, further comprising the step of:

applying a polymerization initiator to said patterned gold layer to provide a self assembled monolayer of a substance that promotes deposition of said adsorbing layer at that location.

17. The method of fabricating a cantilever chemical vapor sensor of claim 10, wherein said step of overcoating said promoter layer with a passivating layer comprises the steps of:

depositing a chromium layer on a region where deposition of said sorbing layer is to be inhibited; and

patterning said chromium layer.

18. The method of fabricating a cantilever chemical vapor sensor of claim 17, further comprising the steps of:

oxidizing said chromium layer to provide an oxidized chromium surface; and depositing a self assembled monolayer of a substance that further passivates said oxidized chromium surface to prevent attachment of polymer initiator to that surface.