Effect of annealing temperature on properties of yttrium-doped ZnO thin films grown by radio-frequency magnetron sputtering

Abstract

The effects of the rapid thermal annealing (RTA) temperature on the structural, morphological, optical, and electrical properties of yttrium-doped ZnO (YZO) thin films were investigated. The YZO thin films were prepared on glass substrates at a deposition temperature of 200 °C using radio-frequency magnetron sputtering. The as-grown thin films were annealed at various RTA temperatures for 30 min. Surface images showed that the crystalline grain sizes of the films increased with increasing RTA temperatures. A strong peak centered at 34.4°, which corresponds to diffraction from the (002) plane of ZnO, was observed for all the thin films annealed at different temperatures. The photoluminescence spectra of the YZO films was observed at approximately 411 nm, and the luminescence intensities showed an increasing tendency with increasing RTA temperature. As the RTA temperature was increased from 400 to 550 °C, the electron concentration and mobility decreased, and the resistivity increased. These results suggest that the properties of YZO thin films deposited by magnetron sputtering can be modulated by varying the RTA temperature.