Low-temperature growth of HgTe and HgCdTe using methylallyltelluride

Abstract

HgTe and HgCdTe (MCT) layers have been grown by organometallic vapor phase epitaxy at low temperature by using methylallyltelluride (MATe), dimethylcadmium (DMCd), and elemental mercury. Use of MATe enabled the growth of layers in the 250–320 °C temperature range, which is 50 °C lower than the growth temperature when diisopropyltelluride is used as the tellurium alkyl, for the same growth rate. The layers were characterized by optical microscopy, double crystal x-ray diffraction, and Fourier transform infrared spectroscopy. Growth at 320 °C resulted in featureless surfaces for both HgTe and HgCdTe layers. The high quality of HgTe layers grown at 320 °C is demonstrated by the very narrow full width at half maximum of x-ray diffraction (29 arcsec), which is comparable to that of the CdTeZn substrates used in this study. MCT layers grown at 320 °C showed sharp interference fringes even for very thin layers, indicating the presence of a very sharp interface with the substrate.