Remote plasma etching of InP in Cl2 and HCl

An attempt is made to add insight into the expectation that in the dry etching of InP, increased temperatures should assist etching even in ion enhanced systems, both in regard to rate and profile. Results for InP and GaAs are compared with each other and results in the literature. At >150 degrees C, the InP etch rate is approximately twice as fast with the plasma on as with the plasma off. The rapid etch rate in molecular Cl/sub 2/ alone, i.e. with the plasma off, confirms that plasma generated radicals are not necessary for etching to occur. This is also observed for GaAs etching in Cl/sub 2/. Thus, molecular Cl/sub 2/ can crack on the surface to form the etch products. At lower temperatures the etch rate enhancement with the plasma on is not as apparent, and a much larger scatter in the data is observed.<>