Electronic properties of heteroepitaxial undoped and n-InSb epilayers using SnTe source by molecular beam epitaxy

Abstract

We report on the electrical characteristics of InSb and n-type doping of InSb layers grown on GaAs substrates using a SnTe captive source by molecular beam epitaxy (MBE). The undoped epilayers are n-type in the temperature range of 10 to 300 K investigated. Doped layer with carrier concentrations ranging from 2×1016/cm3 to 3.2×1018/cm3 with corresponding x-ray full width at half maxima varying from 170–200 arcsec have been achieved. High carrier mobility of 94 098 cm2/V s on lightly doped samples has been achieved. These results suggest SnTe source as being one of the donor dopants of choice for MBE grown InSb epilayers. Temperature and magnetic field dependent Hall and resistivity measurements with various multicarrier conduction analysis techniques indicate three conduction channels for undoped InSb and two conduction channels for doped InSb. They have been used successfully to explain the temperature and thickness dependence of the electrical properties of MBE grown undoped and doped InSb epilayers.