Improvement of the Performance and Stability of Oxide Semiconductor Thin-Film Transistors Using Double-Stacked Active Layers

An amorphous oxide semiconductor thin-film transistor (TFT) with a 47.7-cm² · V^-1 · s^-1 field-effect mobility (μ_FE) and a 1.57-V threshold voltage (V_TH) was produced using a double-stacked active layer composed of a 5-nm indium-zinc-oxide layer and a 60-nm gallium-indium-zinc-oxide (GIZO) layer. The μ_FE is about 2.3 times higher than that of a GIZO TFT, and the V_TH is almost same as that of a GIZO TFT. The stability of this TFT with a double-stacked active layer was superior to that of a GIZO TFT.