Metal oxide thin-film transistors (MOTFTs) are expected to play a vital role in enabling printed transparent, plastic electronics. Compatibility with plastics, however, requires MOTFTs to be scalably processed at low temperatures (T). Herein, we explore blade-coating of indium oxide (In2O3) TFTs via sol-gel and combustion chemistries. We find that the sol-gel process enables amorphous In2O3 TFTs at 200°C with moderate electronic mobility (ca. 1 cm2V-1s-1) which increases to 5 cm2V-1s-1 for 212°C. Combustion synthesis is found to bypass the electronically-active amorphous state leading to an early crystallization onset. Paradoxically, combustion TFTs are found to possess poor charge transport at low-T of 200-250°C. Early nucleation during combustion forms nanocrystalline domains that are deleterious to charge transport. Our results highlight that surprisingly it is not crystallization, rather the absence of it that is required to fabricate high-mobility, low-T bladed In2O3 TFTs.
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