Selectivity tuning by Peroxide concentration for the selective etching of SiGe20 to Si and SiGe40 to SiGe20

Abstract

Using two highly efficient inhibitors, one for silicon and one for SiO2 and SiN it is possible by varying the hydrogen peroxide concentration to achieve tunable formulated chemistry concerning selectivity. So, the same formulation can be used for the selective etching of SiGe25 vs. Si like for GAA applications as well as for the selective etching of SiGe40 vs. SiGe20 like for CFET applications.