Characterization of ternary MgxZn1−xO thin films deposited by electron beam evaporation

MgxZn1−xO (0≤x≤1) thin films were deposited on glass and quartz substrates by electron beam evaporation and effect of the Mg content of the film on its structural, optical and electrical properties were investigated. The structure, surface morphology, optical transmittance, band gap, refractive index and electrical resistivity were found to depend on the Mg content of the film. XRD data revealed that films were polycrystalline in nature. The structure of the films having Mg content in the range of 1–0.74 was cubic, mixed cubic-hexagonal phases for x=0.47 and hexagonal phase for x=0. The composition analysis showed that Mg content in MgxZn1−xO film is high as compared to the corresponding target alloy. It was observed that the optical band gap increases from 3.3 to 6.09 eV, refractive index at 550 nm decreases from 1.99 to 1.75, transmittance increases from about 70% to 90% and electrical resistivity increases from 0.5 to 1.48×106 Ω cm with the increase of Mg concentration in the film from 0 to 1. The results reported in this work are useful for window layer of solar cells and other optoelectronic devices.