Effects of deposition conditions of first InSb layer on electrical properties of n-type InSb films grown with two-step growth method via InSb bilayer

The n-type InSb films were prepared on Si(111) substrates with a two-step growth method via an InSb bilayer. This growth method consists of an initial low-temperature InSb layer growth and a subsequent high-temperature InSb layer growth. In order to obtain a heteroepitaxial InSb film with a high electron mobility, the growth conditions of the first InSb layer were optimized. The first InSb layer was prepared at higher growth temperatures. Moreover, the thickness of the first InSb layer with a lower crystalline quality and poor electrical properties decreased. InSb films prepared with new deposition conditions showed a higher crystalline quality, a lower defects density, and better electrical properties than the films indicated in our previous report. An InSb film with a high electron mobility of 38,000 cm²/(V·s) which shows a high potential for new high-speed device applications was obtained.