Effects of rapid thermal annealing on the morphology and optical property of ultrathin InSb film deposited on SiO2/Si substrate

摘要

Ultrathin InSb films on SiO2/Si substrates are prepared by radio frequency (RF) magnetron sputtering and rapid thermal annealing (RTA) at 300,400,and 500 ℃,respectively.X-ray diffraction (XRD) indicates that InSb film treated by RTA at 500 ℃C,which is higher than its melting temperature (about 485 ℃C),shows a monocrystalline-like feature.A high-resolution transmission electron microscopy (HRTEM) micrograph shows that melt recrystallization of InSb film on SiO2/Si (111) substrate is along the (111) planes.The transmittances of InSb films decrease and the optical band gaps redshift from 0.24 eV to 0.19 eV with annealing temperature increasing from 300 ℃ to 500 ℃,which is indicated by Fourier transform infrared spectroscopy (FTIR) measurement.The observed changes demonstrate that RTA is a viable technique for improving characteristics of InSb films,especially the melt-recrystallized film treated by RTA at 500 ℃.