Structure, electrical and optical properties of dc magnetron sputtered cadmium indate films: Effect of substrate temperature

Abstract: Cadmium indate films were deposited by dc reactive magnetron sputtering onto glass substrates in an oxygen partial pressure of 5×10−4 mbar and at various substrate temperatures in the range 373–673 K. The influence of substrate temperature on the structural, electrical and optical properties of the films was systematically studied. The films formed at substrate temperatures <423 K were amorphous while those deposited at ≥423 K were polycrystalline with cubic spinel structure. The decrease of electrical resistivity and increase of Hall mobility with the increase of substrate temperature were due to the improvement in the crystallinity of the films. The temperature dependence of Hall mobility measurements indicated that the grain boundary scattering of charge carriers was predominant in the films. The films formed at a substrate temperature of 673 K exhibited an electrical resistivity of 3.5×10−4 Ω cm, Hall mobility of 29 cm2 V−1 s−1, optical transmittance of 88%, optical band gap of 3.28 eV and figure of merit of 5×10−2 Ω−1. [Copyright &y& Elsevier]