Hi guys, I am starting to do RIE on III-V semiconductor superlattices. However, most recent literature deals with high-selective etching processes (GaAs <-> AlGaAs). My aims are the following: - etching depth around 1um - high as well as no selectivity against AlAs - high smoothness because I need to pos-process the sample. We have in a parallel plate reactor the following gases available: Cl2, BCl3, SF6, CHF3, CF4, He, N2 and O2. Do you have any hints for recipes? I tried on a GaAs/InGaAs/AlAs/GaAs structure 2sccm Cl2/8BCl3/12CHF3 (or He) but the results are not so encouraging: Very rough etching borders as well as etching bottom (Ra~30nm). Greetings Daniel