High-performance InOx/GaOx bilayer channel thin-film transistors made using persistent high-surface-energy induced by photochemical activation

In this paper, we report high-mobility InOx/GaOx bilayer channel thin-film transistors (TFTs) fabricated using the persistent high-surface-energy characteristic of photochemically activated metal-oxide films. The photochemically-activated metal-oxide films exhibited persistent high surface-energy characteristics compared to a thermally annealed film, which enabled the facile vertical stacking of oxide films using a solution-based process. By using the photochemical activation process as an annealing method and by employing an InOx/GaOx bilayer channel structure, high-mobility oxide TFTs with saturation field-effect mobilities as high as 15.7 cm(2)/V-s were obtained with an average value of 11.2 +/- 1.9 cm(2)/V-s. Various spectroscopic and surface analyses were performed to elucidate the persistent high surface-energy behavior and the dynamic changes in surface states. (C) 2017 Elsevier B.V. All rights reserved.