PREPARATION OF ZNSE SUBSTRATES BY PVD AND SELECTIVE ETCHING

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