Patent ID: 8796679

Claim:
A thin film transistor, comprising: a substrate; an IGZO active layer on the substrate, the IGZO active layer, an atomic % of In in the IGZO active layer being between 55 atomic % and 75 atomic %, and an atomic % of Ga in the IGZO active layer being at least 10 atomic %, and the IGZO active layer including a channel region, a source region, and a drain region; a gate electrode overlapping the channel region and insulated from the IGZO active layer by a gate insulator; and source and drain electrodes contacting the source and drain regions, respectively, wherein the IGZO active layer is formed by: depositing ions including In, Ga, and Zn from a first target including In, Ga, and Zn; and depositing ions including In from a second target having a different atomic composition from the first target, the second target including InZnO, and controlling the deposition of ions from the second target so as to adjust an atomic % of In in the IGZO active layer to be between 55 atomic % and 75 atomic %.