Luminescence study of II-VI-based thin films deposited by close-spaced vacuum sublimation technique

Abstract

CdSe, Cd1-xZnxTe ternary compound, CdS:Dy rare-earth element doped II-VI compound) at different substrate temperatures is performed. In all cases of studied samples they are deposited onto non-oriented substrates using the close-spaced vacuum sublimation technique (CSVS) which makes a possibility to obtain films with optimal crystalline and optical quality. The study of the PL spectra of the investigated films makes it possible to determine their optimal growth conditions in order to obtain the films of good optical quality. The obtained results are in good agreement with the structural investigations, which we have carried out earlier using the X-ray diffraction technique. In all cases of investigated samples on PL-spectra there were observed lines that correspond to the residual impurities, which are typical for II-VI compounds (Li, Na, Cu, P). Moreover there were observed an additional lines which may be caused by the presence of point defects in crystalline structure, donor- acceptor pairs recombination processes, phonon replicas, etc.