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

摘要

A method for the manufacture, formation, and removal of porous layers in a semiconductor substrate having at least a surface acting as a cathode. The method comprises applying a solution comprising negative Fluorine (F<->) ions between the surface of the semiconductor substrate and an anode. The method further comprises applying a predetermined current between the anode and the cathode. The method further comprises maintaining the predetermined current at substantially the same current value for a sufficient amount of time to obtain a low porosity layer at said surface. A high porosity layer positioned under the low porosity layer is also obtained by the method of the invention.