Photoluminescence of ZnTe homoepitaxial layers grown by metalorganic vapor-phase epitaxy at low pressure

Abstract
Photoluminescence (PL) spectra have been investigated at liquid-He temperature in the ZnTe layers grown by metalorganic vapor-phase epitaxy. The epitaxial layer exhibits the spectra characterized by a neutral acceptor bound-exciton line in the near-band edge and the donor-acceptor pair emission in the wavelength range of 550–580 nm. At the low substrate temperature or low transport rate ratio of diethyltelluride to dimethylzinc, the spectrum of layer becomes dominated by this donor-acceptor pair emission. From the results of secondary-ion mass spectrometry analysis and PL property, it is concluded that Na and Cl are important impurities in the layer.