Effect of growth temperature on the properties of hydrogenation Al-doped ZnO films

Abstract

This study examined the effect of growth temperature on the electrical and optical properties of hydrogenated Al-doped zinc oxide (AZO:H) thin films deposited by rf magnetron sputtering using a ceramic target (98 wt.% ZnO, 2 wt.% Al2O3). Various AZO films on glass were prepared by changing the substrate temperature from room temperature to 200°C. It was shown that intentionally incorporated hydrogen plays an important role on the electrical properties of AZO : H films by increasing free carrier concentration. As a result, in the 2% H2 addition at the growth temperature of 150°C, resistivity of 3.21×10-4 Ω cm, mobility of 21.9 CM2/V-s, electric charge carrier concentration of 9.35×1020 CM-3 was obtained. The AZO: H films show a hexagonal wurtzite structure preferentially oriented in the (002) crystallographic direction.