Selective area deposition of a-C:H films as masks for anisotropic etching of crystalline silicon in aqueous potassium hydroxide

摘要

Amorphous hydrogenated carbon (a-C:H) thin films deposited by r.f chemical vapor deposition were investigated as a chemically resistant material for masking anisotropic etching of crystalline silicon by aqueous solution of KOH. Films withthicknesses varying from 50 to 80nm were Success fully patterned on silicon slices by the lift-off process. Then the samples were submitted to one aqueous etchant solution of KOH for 1 h at a temperature of 78℃. The inspection showed well defined etching pattern indicating the high chemical resistance of the a-C:H film to the aqueous KOH solution.