Mobility of charge carriers in double-layer PbTe/PbS structures

The method of hot-wall epitaxy is used to grow epitaxial heterostructures of p-PbTe/n-PbS on BaF2 substrates. Hall-effect measurements are analyzed in order to obtain the dependence of the effective carrier mobility on thickness and temperature in the ranges 0.1–2 µm and 100–300 K, respectively. It is found that this mobility depends on the thickness of the sample and on the individual thicknesses of its constituent layers. The effective mobility is calculated under the assumption that charge carriers are scattered by the surface of the structure and by dislocations that form at the heterojunction boundary.