Photoluminescence from CdTe/sapphire films prepared by molecular beam epitaxy

Abstract

Photoluminescence studies at 77 K are reported for CdTe/sapphire films prepared by molecular beam epitaxy. The CdTe/sapphire epilayers exhibited very bright photoluminescence spectra that were dominated by the near-edge emission band at 1.58 eV. The best CdTe/sapphire film proved to be the brightest source of luminescence of any CdTe specimen studied in our laboratories, including homoepitaxial films and bulk hydroplane polished samples. The CdTe/sapphire films also exhibited the best lateral uniformity as manifested by a nearly constant luminescence intensity over their surfaces. These results provide new evidence that high quality CdTe epitaxy on sapphire has been achieved.