High performance of ultralow temperature polycrystalline silicon thin film transistor on plastic substrate

Abstract

A high performance ultralow temperature polycrystalline silicon (poly-Si) thin film transistor (TFT) was obtained on a plastic substrate using the optimization of a triple layered buffer process for a suppression the damage on plastic substrate during laser dopant activation, the high quality SiO2 interface layer formation between the gate dielectric film and the poly-Si film using plasma oxidation, and a successful crystallization of large grain poly-Si films with a sequential lateral solidification (SLS) method. High performances with field effect mobilities of 180 and 62cm2V−1s−1, threshold voltages of 1.4 and −1.6V and sub-threshold swings of 0.78 and 0.92V/decade were obtained for n-channel metal–oxide-semiconductor (nMOS) and p-channel metal–oxide-semiconductor (pMOS) TFT on plastic substrate, respectively.