H | ELECTRICITY |
01 | BASIC ELECTRIC ELEMENTS |
L | SEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR |
21 | Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof |
02 | Manufacture or treatment of semiconductor devices or of parts thereof |
04 | the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer |
18 | the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials |
30 | Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 |
31 | to form insulating layers thereon, e.g. for masking or by using photolithographic techniques |
3105 | After-treatment |
31051 | Planarisation of the insulating layers |
31053 | involving a dielectric removal step |
31055 | the removal being a chemical etching step, e.g. dry etching |
31056 | the removal being a selective chemical etching step, e.g. selective dry etching through a mask |