FIELD EFFECT TRANSISTOR USING OXIDE SEMICONDUCTOR AND METHOD FOR MANUFACTURING THE SAME

摘要

Disclosed is a field effect transistor which comprises, on a substrate, at least a semiconductor layer, a protective layer of the semiconductor layer, a source electrode, a drain electrode, a gate insulating film and a gate electrode. The source electrode and the drain electrode are connected with each other through the semiconductor layer. The gate insulating film is arranged between the gate electrode and the semiconductor layer. At least one side of the semiconductor layer is provided with the protective layer. The semiconductor layer is composed of a complex oxide containing In (indium), Zn (zinc) and Ga (gallium) at atomic ratios satisfying the following formulae (1)-(3). In/(In + Zn) = 0.2-0.8 (1) In/(In + Ga) = 0.59-0.99 (2) Zn/(Ga + Zn) = 0.29-0.99 (3)