Determination of Real Substrate Temperature during Sputtering by Nanostructure Analysis of Phase Separating Cobalt-Indium Tin Oxide System

The real substrate temperature during sputtering was estimated by adopting a phase separation system of cobalt indium tin oxide thin film. The nanostructure, consisting of Co fibers in an In2O3-SnO2 (ITO) matrix was formed during sputtering through surface diffusion. The increase of the substrate surface temperature was determined based on sputtering time and substrate temperature dependence of the Co fiber diameter. The activation energy of mutual surface diffusion was determined as being 0.57 eV using values of the real substrate temperature. The increase of real substrate temperature due to the increase of power density was also estimated.