Patent ID: 8343878

Claim:
A method of plasma etching Ga-based compound semiconductors, the method comprising: providing a process chamber and a source electrode adjacent to the process chamber, the process chamber containing a sample comprising a Ga-based compound semiconductor, the sample being in contact with a platen electrically connected to a first power supply, and the source electrode being electrically connected to a second power supply; flowing SiCl 4 gas into the chamber; flowing Ar gas into the chamber; supplying RF power to the platen at a first power level using the first power supply; supplying RF power to the source electrode using the second power supply; generating a plasma based on the gases in the process chamber; after generating the plasma, supplying RF power to the platen at a second power level lower than the first power level and no greater than about 30 W; etching regions of a surface of the sample adjacent to one or more masked portions of the surface at an etching rate of no more than about 25 nm/min to create a substantially smooth etched surface.