The effect of processing parameters on the properties of Ga-doped ZnO thin films by RF magnetron sputtering

The 3 wt% Ga-doped ZnO (GZO) thin films were prepared on glass substrates by RF magnetron sputtering with different processing parameters such as RF powers, substrate temperatures and Ar working pressures. Crystallinity and electrical properties of GZO films were investigated. The X-ray diffraction results showed that all the GZO films were grown as a hexagonal wurtzite phase with highly c-axis preferred out-of-plane orientation. The electrical properties of GZO films were strongly related to processing parameters. With increasing the processing parameter values, the electrical properties of GZO films were improved up to at 350 °C, 200 W and 6 mTorr, above that they became worse at 400 °C and 7.5 mTorr. The film showed the lowest resistivity of 3.45 × 10−4 Ωcm when the film was prepared in the optimized conditions of processing parameters of 350 °C, 6 mTorr, and 200 W.