Structure and Electric Properties in Tin-Doped Zinc Oxide Films Synthesized by Pulsed Laser Deposition

Tin-doped zinc oxide, , films were prepared using a pulsed laser deposition method to elucidate the effects of Sn doping in ZnO films. The film obtained was ⟨001⟩-oriented wurtzite type when the Sn concentration was 10% or less, while ⟨111⟩-oriented was the major phase when the Sn concentration was more than 10%. The lattice parameters of the wurtzite-type increased with increasing Sn concentration, and Raman spectra showed corresponding systematic changes with Sn concentration. However, the electron concentration measured by the Hall effect was not proportional to the Sn concentration, although the tetravalent Sn ion, a possible double-donor impurity, was introduced into the ZnO lattice. The charge compensation mechanism in the films is discussed in relation to imperfections in the crystalline structure.