Gd-doped ZnO Grown by Simultaneous Sputtering at Different RF Power

Gd-doped ZnO thin films have been deposited using the simultaneous process of RF and DC sputtering on top of glass substrates at room temperature. 50W to 125 W of RF power has been adjusted to the Gd target. The structural and optical properties were analyzed to investigate the impact of sputtering power against the deposited of Gd-doped ZnO thin films. The XRD results show that (002) peaks of ZnO dominantly for all films with the structure of hexagonal wurtzite. Gd was confirmed incorporated into ZnO since no other peaks appear on XRD patterns. The crystallite size was inversely proportional to FWHM upon increasing of sputtering power while the deposition rate and thickness of the films was increase. The Gd-doped ZnO thin film shows high transparency with 80 % of transmittance at a visible region of wavelength. The optical band gap depicts a blue-shift towards higher power of sputtering which resulting in the Burstein-moss effect. These results imply that the structural and optical properties of the Gd-doped ZnO thin films were significantly affected by the power of RF sputtering.