Effects of sputtering power on the properties of ZnO:Ga films deposited by r.f. magnetron-sputtering at low temperature

Gallium-doped zinc oxide (ZnO:Ga) films were prepared on glass substrates by r.f. magnetron sputtering at low substrate temperature. Structural, electrical and optical properties of the ZnO:Ga films were investigated in terms of the preparation conditions. The obtained films were polycrystalline with a hexagonal wurtzite structure and preferentially oriented in the (0 0 2) crystallographic direction. The transmittance of the ZnO:Ga films in the visible range was over 85%. The lowest resistivity and sheet resistance for the ZnO:Ga films were about 3.9×10−4 Ω cm and 4.6 Ω/□, respectively.