Study on Epitaxial Growth of High-Quality InSb Materials

Abstract

This paper discusses the optimization of the growth temperature and Sb/In ratio of 1 µm InSb thin films grown on GaAs substrates by molecular beam epitaxy due to the InSb materials with larger lattice constants have smaller growth windows. The results show that atomic steps can be clearly seen in InSb thin films grown at 420 °C with a Sb/In ratio of 6. The InSb material grown under this condition has the smallest FWHM, indicating the best crystal quality. At the same time, the highest electron mobility measured at room temperature is 38860 cm² V⁻¹ s⁻¹. The transport properties and crystal quality of InSb/Al_xIn_1-xSb heterostructures corresponding to different Al compositions are also studied. The results show that as the Al component increases, dislocation scattering caused by lattice mismatch affects the electron mobility of the channel layer. The highest electron mobility of InSb/Al_xIn_1-xSb heterostructures obtained is 18900 cm² V⁻¹ s⁻¹ at room temperature.