Effects of annealing on InAsSb films grown by the modified LPE technique

Abstract

We have studied the annealing effects on InAsSb thick films grown by the modified liquid phase epitaxy (LPE) technique. Appropriate annealing treatment can efficiently eliminate Sb vacancy and stain which are formed during growing process, thus it is necessary to study the influence of annealing condition (temperature, ambient, time and cooling rate) on the properties of InAsSb epilayer. The X-ray diffraction measurement (XRD) showed the annealed InAsSb films were polycrystalline with (111)-preferred orientation, except for the two samples annealed with 350 °C for 15 hours and with rapid cooling rate, respectively, which exhibited a (100)-preferred orientation. The Fourier transform infrared (FTIR) revealed a cut off wavelength more than 10 μm for the samples. Also, the infrared transmittance would be improved due to decreasing of film defects by appropriate annealing treatment. Measurement of electrical properties for samples revealed the increase of electron mobility and the reduce of carrier concentration at 77K when keeping anneal temperature low at 350 °C and extending anneal time, indicating the electrical improvement of the InAsSb layers.