Preparation of ZnSe substrates by PVD and selective etching

Abstract

In order to obtain a ZnSe substrate, very thick single-crystalline ZnSe layers have been grown on a GaAs substrate using a PVD (physical vapor deposition) method. The ZnSe layer with thickness of about 370 μm was obtained after 100 h growth. Then the GaAs substrate was easily removed using the selective etchant of 4H 2SO 4 : 1H 2O 2 : 1H 2O, since the etching rates for GaAs(1 0 0) and ZnSe(1 0 0) were 1.6 and 0.03 μm/min, respectively, at 60°C. Using this technique, ZnSe substrates with large area will be easily produced.