Characterization of zinc–tin–oxide films deposited by radio frequency magnetron sputtering at various substrate temperatures

Abstract Zinc–tin–oxide (ZTO) thin films were grown by radio frequency magnetron sputtering on glass substrates at various substrate temperatures. The effects of substrate temperature on the crystalline behavior and electrical and optical properties of the films were studied. The ZTO films were amorphous and maintained their stable amorphous state up to a substrate temperature of 350 °C. With increasing substrate temperature, the ZTO films underwent an amorphous-to-crystalline phase transition. The Hall mobility of the films was in the range of 22.7–23.5 cm 2 /V s in the amorphous phase and 15.4–19.6 cm 2 /V s in the crystalline phase. The carrier concentration reached 8.287 × 10 19  cm − 3 , resulting in a minimum resistivity of 8.75 × 10 − 3  Ω·cm in the film deposited at 750 °C. The average transmittance in the visible region was ≥ 85%, and the band gap showed a red-shift in the amorphous phase and a blue-shift in the crystalline phase.