TRANSPORT-PROPERTIES OF HG0.80MG0.20TE GROWN BY MOLECULAR-BEAM EPITAXY

Variable magnetic-field Hall measurement has been used to investigate the transport properties in Hg0.80Mg0.20Te molecular beam epitaxy film s in the temperature range from 1.5 to 250 K. The experimental data ha ve been analyzed by using a hybrid approach consisting of the mobility spectrum (MS) technique followed by a multicarrier fitting procedure. Both the Shubnikov- de Haas measurements and the hybrid MS+MCF approa ch show three- and two-dimensional electronic behaviors. The two-dimen sional electrons, with mobility in the range of 1-3 x 10(3) cm(2)/V s and a sheet density about 10(12) cm(-2), are found and come from an ac cumulation layer near the HgMgTe-CdTe interface or the HgMgTe-vacuum i nterface. The temperature-dependent evolution of the bulk electron mob ility indicates that the scattering mechanism in HgMgTe is very simila r to that in HgCdTe, that is, ionized impurity scattering dominates at low temperature while lattice scattering dominates above 100 K. (C) 1 998 American Institute of Physics. [S0021-8979(98)02623-1].