Study of the Surface Texture of Magnetron Sputtered Transparent Conducting ZnO:Al films by Atomic Force Microscopy

Abstract

Abstract: Transparent conducting ZnO: Al films with proper surface texture have been developed on glass substrate at 3500C by rf-magnetron sputtering under Ar and Ar+O2 gas ambients. ZnO:Al films exhibit low resistivity (~ 8.9x10-4 Ω-cm), and high optical transmittance (T~ 85% to 90%) in visible region. Study of surface texture ZnO:Al films by dry (hydrogen plasma) etching and wet chemical etching in diluted 0.5% HCl acid solution have been reported in this paper. Due to hydrogen plasma etching surface topography as well as morphology of ZnO:Al films is modified into suitable texture for light scattering. But surface texture is deteriorated drastically for wet chemical etched films. Electrical properties have been improved slightly and optical transmittance remains undeviated due to H-plasma etching but significant changes in electrical and optical properties have been observed in wet chemical etching. Keywords: ZnO:Al films, Surface Texture, Wet Chemical etching, Atomic Force Micrograph, Thin film solar cell