Effect of The Cu Doping on The Structural and Optical Properties of AlSb Thin Films Deposited by Thermal Evaporation Method

Abstract

Abstract AlSb thin film was prepared on a glass substrate with a thickness of (200 nm) at room temperature using the thermal evaporation technique under high vacuum conditions (10−6 mbar). The effect of Cu doping at ratios (1%, 3% and 5%) on the structural and optical properties were investigated. The structural properties of the films were evaluated by X-Ray Diffraction technique (XRD) and atomic force microscopy (AFM). The optical properties of the films were measured using the (UV-Vis ) spectra in the ranges from 400 to 1000 nm. XRD results showed that all the samples have a polycrystalline cubic structure, and the average grain size of AlSb increases with increasing the Cu ratios. According to the AFM analysis, it is noticed that the average surface roughness (RMS) of AlSb nanocubic thin film decreases with increasing Cu doped concentration. From UV–Vis absorption spectra, it is noticed that all the samples have high absorption in the visible region, and the direct energy gap values for the samples were 1.83 eV, 1.81 eV, 1.80 eV, and 1.78 eV for pure, 1% Cu, 3% Cu and 5% Cu respectively.