Plasma Oxidation Effect on Ultralow Temperature Polycrystalline Silicon TFT on Plastic Substrate

The TFT performances were enhanced and stabilized by plasma oxidation of the polycrystalline Si surface prior to the plasma enhanced atomic layer deposition of $Al_2O_3$ gate dielectric film. We attribute the improvement to the formation of a high quality oxide interface layer between the gate dielectric film and the poly-Si film. The interface oxide has a predominant effect on the TFT's characteristics, and is regulated by the gap distance between the electrode and the polycrystalline Si surface.