Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1792242 | Journal of Crystal Growth | 2011 | 6 Pages |
Abstract
3 wt% Ga-doped ZnO (GZO) thin films were deposited on Al2O3 (0 0 0 1) substrates by RF magnetron sputtering at different growth temperatures ranging from 350 to 750 °C. The crystallinity, microstructure, epitaxial nature, and optical and electrical properties of the GZO thin films were examined by X-ray diffraction (XRD), transmission-electron microscopy (TEM), UV-visible spectroscopy and Hall measurements. XRD and TEM showed that the GZO thin films deposited below a growth temperature of 450 °C grew epitaxially with an orientation relationship of (0001)[112¯0]GZOâ(0001)[112¯0]Al2O3. However, the GZO thin films deposited above 550 °C were in polycrystalline hexagonal wurtzite phase with c-axis preferred. The crystallinity of the GZO thin films deteriorated with increasing growth temperature. The GZO thin film deposited at 350 °C showed the lowest electrical resistivity of 1.13Ã10â4 Ω cm. The electrical properties of the GZO thin films also deteriorated with increasing growth temperature. UV-visible spectroscopy showed that the GZO thin films are highly transparent (from 75% to 90%) in the visible region. In addition, the band gap of the deposited thin films decreased from 3.5 to 3.2 eV with increasing growth temperature.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
Seung Wook Shin, Gyoung Hoon Lee, A.V. Moholkar, Jong-Ha Moon, Gi-Seok Heo, Tae-Won Kim, Jin Hyeok Kim, Jeong Yong Lee,