Optical Properties of Molecular Beam Epitaxy Grown ZnSe on GaAs

Photoluminescence studies of molecular beam epitaxy grown ZnSe-on-GaAs layers are presented. The high sensitivity of the PL technique allowed for identification unintentional dopants in pure ZnSe sample. Characteristic photoluminescence lines due to extended defects were observed. The experimental results obtained show a correlation between intentional doping level and extended defects concentration. We conclude also that even though molecular beam epitaxy layers are grown at low temperature, the self-compensation mechanism may still be important. For heavily doped sample edge emission is deactivated likely due to efficient energy transfer link with deep donor-acceptor pair bands