Effect of Si substrate modification on improving the crystalline quality, optical and electrical properties of thermally-evaporated BaSi2 thin-films for solar cell applications

Abstract

We have grown orthorhombic barium disilicide ([Formula: see text]) thin-films on modified silicon (Si) substrates by a thermal evaporation method. The surface modification of Si substrate was performed by a metal-assisted chemical etching method. The effects of etching time [Formula: see text] on crystalline quality as well as optical and electrical properties of the [Formula: see text] films were investigated. The obtained results showed that substrate modification can enhance the crystalline quality and electrical properties; reduce the light reflection; and increase the absorption of the [Formula: see text] thin-films. The [Formula: see text] of 8 s was chosen as the optimized condition for surface modification of Si substrate. The achieved inferred short-circuit current density, Hall mobility, and minority carrier lifetime of the [Formula: see text] film at [Formula: see text] of 8 s were [Formula: see text], [Formula: see text], and [Formula: see text]s, respectively. These results confirm that the [Formula: see text] thin-film evaporated on the modified Si substrate is a promising absorber for thin-film solar cell applications.