Growth of undoped ZnMgTe layers by metalorganic vapour phase epitaxy

Abstract

The ternary undoped Zn1-xMgxTe layers have been grown on (100) ZnTe substrates by atmospheric pressure metalorganic vapour phase epitaxy (MOVPE) using dimethylzinc (DMZn), bis-methylcyclopentadienyl-magnesium ((MeCp)2Mg) and diethyltelluride (DETe). The effects of the transport rates of DMZn and (MeCp)2Mg upon the Mg composition the low temperature photoluminescence (PL) property of Zn1-xMgxTe layer have been investigated. The PL spectra exhibit two distinctive luminescence bands, i.e. excitonic emission (band A) and donor-acceptor pair recombination emission (band B). The intensity ratio of the peak A to peak B increases with decreasing DMZn transport rate, indicating that the optical property of the layer is improved. The control of the Mg composition by (MeCp)2Mg transport rate under VI/II ratios of one to two has an advantage in achieving both the controllability of Mg composition and good optical property of undoped Zn1-xMgxTe layer grown by atmospheric pressure MOVPE. © 2008 IOP Publishing Ltd.