Morphology and structure evolution of tin-doped indium oxide thin films deposited by radio-frequency magnetron sputtering: The role of the sputtering atmosphere

摘要

The microstructure and morphology evolution of tin-doped indium oxide (ITO) thin films deposited by radio-frequency magnetron sputtering in different sputtering atmospheres were investigated by X-ray diffraction, X-ray reflectivity, and atomic force microscopy. The surface roughness w increases with increasing film thickness d_f, and exhibits a power law behavior w ～ d_f~β. The roughness decreases with increasing O_2 flow, while it increases with increasing H_2 flow. The growth exponent β is found to be 0.35, 0.75, and 0.98 for depositions in Ar/10%O_2, pure Ar, and Ar/10%H_2 atmospheres, respectively. The correlation length ζ increases with film thickness also with a power law according to ζ ～ d_f~z with exponents z = 0.36, 0.44, and 0.57 for these three different gas atmospheres, respectively. A combination of local and non-local growth modes in 2+1 dimensions is discussed for the ITO growth in this work.