Properties of InSb single-crystal thin films sandwiched by Al0.1In0.9Sb layers with 0.5% lattice mismatch grown on GaAs

We studied the properties of InSb single-crystal thin films sandwiched by Al0.1In0.9Sb layers (with 0.5% lattice mismatch between InSb and Al0.1In0.9Sb) grown by molecular beam epitaxy on a GaAs substrate. The electron mobility of these InSb thin films was significantly higher and the electron density was very small in thin regions of less than 0.5 μm compared to InSb thin films directly grown on the GaAs substrate. These results mean that the Al0.1In0.9Sb layers almost eliminated the large lattice mismatch effect observed at the InSb/GaAs hetero-interface. The dependence of electron mobility and electron density on temperature is also discussed with respect to the InSb thickness and Sn doping.