Optical and electrical properties of gallium-doped Mg15Zn85O thin films

Ga-doped Mg0.15Zn0.85O thin films have been grown on fused silica substrates at 350 degrees C with four different gallium concentration values using pulsed laser deposition. X-ray diffraction results indicate that these films were textured with c-plane parallel to the substrate surface. The band-gap of the films were determined based on the absorption measurements. The bandgaps of the Ga-doped thin films shifted to higher energy with respect to that of the unalloyed Ma(0.15)Zn(0.85)O thin film due to the band filling effect of electron distribution in the conduction band. Resistivity of the films was measured with four-point probe at temperatures from 295 K to 15 K. The activation energy of the gallium dopants was extracted by fitting the temperature dependent curve of resistivity.