Influence of Cd diffusion on the structure and photoluminescence of CdSe/ZnSe multiple quantum wells

In this paper, we have fabricated a 20 period CdSe/ZnSe MQW's on (001) orientated GaAs grown by metalorganic chemical vapor deposition under se-rich condition at the growth temperature of 500 degree(s)C. CdSe/ZnSe MQW's structure was characterized by means of x-ray diffraction and Raman scattering. These experimental results indicated the formation of new Cd1-xZnxSe layers and the existence of Cd and Zn vacancies in CdSe/ZnSe MQW's. The photoluminescence spectra of CdSe/ZnSe MQW's at low temperature was composed of a very strong and narrow band A at 2.4 eV and a weak and broadened band B at 2 eV. In order to understand the influence of Cd diffusion on the structure and photoluminescence (PL) of CdSe/ZnSe multiple quantum wells (MQW's), a new model of Cd diffusion in CdSe/ZnSe MQW's was given. Based on the simulation of Cd diffusion in CdSe/ZnSe MQW's and the calculation of the envelop-function approximation, the origin of PL of CdSe/ZnSe MQW's was discussed.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.