Structural, optical, optoelectrical and photovoltaic properties of the thermally evaporated Sb2Se3 thin films

Abstract

Production of inexpensive and promising light-absorbing materials is very important in photovoltaic device applications. In this study, we investigate the preparation of good-quality antimony selenide (Sb2Se3) thin films via thermal evaporation procedure with different thicknesses (241, 315, 387 and 429 nm). The analysis of the X-ray diffraction examination of the Sb2Se3 thin films demonstrates that the as-deposited Sb2Se3 thin films are polycrystalline with a single-phase orthorhombic structure. The elemental composition analysis of the evaporated Sb2Se3 thin film established that the as-deposited film has near stoichiometric composition of the compound. The linear optical results of the Sb2Se3 thin films revealed that the films show optical direct transitions and optical energy gaps in the range 1.12–1.05. The optoelectrical parameters of the Sb2Se3 thin films (ratio of the charge carrier concentrations to the effective mass $$N_{\text{opt}} m$$, optical electronegativity $$\xi_{\text{opt}}$$ and the lattice dielectric constant, $$\varepsilon_{L}$$) were estimated. The analysis of nonlinear optical parameters of the Sb2Se3 thin films reveals the increase of the film thickness combined with increase in the nonlinear refractive index. The Al/n-Si/Sb2Se3/Ag heterojunction was produced by the thermal evaporation technique. The photovoltaic constants of the Al/n-Si/Sb2Se3/Ag heterojunction were estimated from the J–V curve and demonstrate a solar efficiency of 4.03%.