Combinatorial approach to thin-film transistors using multicomponent semiconductor channels: An application to amorphous oxide semiconductors in In–Ga–Zn–O system

A combinatorial approach was applied to thin-film transistors (TFTs) using amorphous In–Ga–Zn–O semiconductor channels. A large number of TFTs, having n-type channels with different chemical compositions, were fabricated simultaneously on a substrate. A systematic relation was clarified among the compositional ratio of In:Ga:Zn, oxygen partial pressure in film deposition atmosphere, and TFT characteristics. The results provide an experimental basis to understand the roles of each metallic element in the In–Ga–Zn–O system. This information leads to a guideline to tune the metallic compositions for required TFT specifications.