High mobility, n-type transparent thin-film transistors (TTFTs) with a zinc indium oxide (ZIO) channel layer are reported. Such devices are highly transparent with 85% optical transmission in the visible portion of the electromagnetic spectrum. ZIO TTFTs annealed at 600 °C operate in depletion-mode with threshold voltages 20 to 10V and turn-on voltages 3V less than the threshold voltage. These devices have excellent drain current saturation, peak incremental channel mobilities of 4555cm2V1s1, drain current on-to-off ratios of 106, and inverse subthreshold slopes of 0.8Vdecade. In contrast, ZIO TTFTs annealed at 300 °C typically operate in enhancement-mode with threshold voltages of 010V and turn-on voltages 12V less than the threshold voltage. These 300 °C devices exhibit excellent drain–current saturation, peak incremental channel mobilities of 1030cm2V1s1, drain current on-to-off ratios of 106, and inverse subthreshold slopes of 0.3Vdecade. ZIO TTFTs with the channel layer deposited near room temperature are also demonstrated. X-ray diffraction analysis indicates the channel layers of ZIO TTFTs to be amorphous for annealing temperatures up to 500 °C and polycrystalline at 600 °C. Low temperature processed ZIO is an example of a class of high performance TTFT channel materials involving amorphous oxides composed of heavy-metal cations with (n1)d10ns0(n4) electronic configurations.

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