Excitonic Luminescence Spectra and Electrical Transport Properties of Photosensitive CdSe Layers Grown on Mica in a Quasi-Closed System

CdSe layers having high photosensitivity (photocurrent to dark current ratio of 6.2 × 104) and an extremely low carrier concentration (9 × 1011 cm–3) have been grown on muscovite mica by thermal evaporation in a quasi-closed system. These results are of interest for producing materials for position-sensitive semiconductor photodetectors based on CdSe layers. We have demonstrated that the 78-K cathodoluminescence spectra of the cadmium selenide layers grown at 853 K have a single line, corresponding to radiative annihilation of free A-excitons. The spectra of the layers grown at 833 K show a line of free A-excitons and its first phonon replica.