Single-step sputtered Cu2SnSe3 films using the targets composed of Cu2Se and SnSe2

Cu2SnSe3 thin films were prepared by single-step D.C. sputtering at 100–400 °C for 3 h using targets composed of Cu2Se and SnSe2 in three different ratios of 2/1 (target A), 1.8/1 (target B), and 1.6/1 (target C). The advantages of self-synthesized SnSe2 instead of commercially available SnSe for depositing Cu2SnSe3 thin films were demonstrated. Effects of target composition and substrate temperature on the properties of Cu2SnSe3 thin films were investigated. Structure, surface morphology, composition, electrical and optical properties at different process conditions were measured. The 400 °C-sputtered films obtained from target B display with direct band gap of 0.76 eV, electrical resistivity of 0.12 Ω cm, absorption coefficient of 104–105 cm− 1, carrier concentration of ∼ 1.8 × 1019 cm− 3, and electrical mobility of 2.9 cm2/V s.