Step Hall Measurement of InSb Films Grown on Si(111) Substrate Using InSb Bilayer

Abstract

We investigated the in-depth profile of electrical properties of InSb films grown on Si(111) substrates using various InSb bilayers. The InSb bilayers were prepared using three types of initial In-induced surface reconstructions on Si(111) substrates such as √3×√3-In, 2×2-In, and √7×√3-In. The InSb films were grown using a two-step growth procedure. In the growth procedure, the 1st layer was deposited using at a low growth rate of about 1 Å/min. The in-depth profile of the electrical properties of the InSb films was obtained by reciprocally repeated chemical etching and Hall measurement. The electron mobility of the films was gradually decreased with decreasing thickness. The electron mobility at room temperature of the InSb film grown via √7×√3-In surface reconstruction was estimated to be about 61,000 cm 2 /(V·s) in the region near the surface and about 20,000 cm 2 /(V·s) in the region approximately 0.2 µm from the InSb/Si interface. These indicate that the high electron mobility of the samples grown on the InSb bilayer using at a low growth rate during the first layer deposition originated from the reduction of the regions with low electron mobility near the InSb/Si interface.