Method for the formation and lift-off of porous silicon layers

Abstract

The present invention concerns a method for the manufacture of porous layers in a semiconductor substrate, comprising the following steps: Providing a semiconductor substrate comprising at least one surface, said substrate serving as an cathode, Providing a anode, Applying a solution comprising F− ions, suitable for removing material from said substrate, between said surface and said anode, Applying a predetermined current between said anode and said cathode, and Maintaining said solution and said current a sufficient amount of time to obtain a low porosity surface at said surface and a high porosity surface positioned under said low porosity surface.

Dependencies are inferred from the claim text.