Solution processed invisible all-oxide thin film transistors

Abstract

We report on a fully transparent solution processed thin-film transistor (TFT) device with oxide semiconductor and oxide electrode. Selective doping into the sol–gel derived ZnO materials tailors the electrical properties to range from metallic to semiconducting characteristics. Integration of a spin-coated zinc tin oxide (ZTO) semiconductor with an ink-jet-printed zinc indium oxide (ZIO) electrode creates a transparent TFT with high performance and good transparency (∼90%). Use of the same ZnO-based oxide materials in a TFT allows for the formation of good electrical contacts characterized by low contact resistance, comparable to those with a vacuum-deposited Al electrode. Our results suggest that the solution-processed ZnO-based TFT has great potential to work as a building block for future printed transparent electronics.