Etching and cathodoluminescence studies of ZnSe

Epitaxial thin films of ZnSe grown on GaAs substrates were reactive ion etched using BCl₃ /Ar gas mixtures. Using an optimized etching process, photolithographically defined micrometer sized structures were etched several micrometers deep with straight sidewalls and smooth surfaces. Cathodoluminescence was measured from both etched and unetched surfaces at room temperature. Luminescence intensities of etched surfaces are shown not to be degraded by the reactive ion etching process. Cathodoluminescence intensities of etched pixels with exposed sidewalls were found to be greater than the intensities measured from unetched flat surfaces. This suggests the possibility of efficient etched light-emitting structures.