Structural and optical characterization of epitaxial layers of CdTe/PbTe grown on BaF2 (111) substrates

CdTe and CdTe/PbTe layers were grown on BaF2 (111) substrates by molecular beam epitaxy technique employing PbTe, CdTe, and Te2 effusion cells. The layers are monocrystalline with (111) crystal orientation and exhibit x‐ray rocking curve FWHM parameter of 100‐300 arcsec for PbTe and CdTe. The well defined streaky RHEED diffraction pattern was observed during the process of growth of both layers indicating a two‐dimensional mode of growth. For the optical characterization of CdTe layers, the photoluminescence spectra were studied at T = 4.2 K in 750–870 nm (1.40–1.65 eV) spectral range using pulsed excitation at 2.35 eV by Nd:YAG laser. In CdTe/BaF2 layers, the dominant photoluminescence peak is observed at 785 nm and corresponds to the radiative recombination of excitons bound to neutral acceptors. In CdTe/PbTe/BaF2 heterostructures with thick PbTe buffer, no photoluminescence is observed in the spectral range studied. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)