The metal-induced crystallization of poly-Si and the mobility enhancement of thin film transistors fabricated on a glass substrate

Abstract

In this study, we report on the fabrication of poly-crystalline silicon (poly-Si) using the metal-induced crystallization (MIC) method and its application to thin film transistors (TFTs). The top gate of the p-type TFTs, whose active layer used MIC poly-Si annealed for 1 h at 650 °C, showed a field effect mobility ( μ FE) of 7.5 cm 2/V s. By increasing the crystallization time to 5 h, the quality of the MIC poly-Si was improved. The μ FE increased from 7.5 to 15 cm 2/V s. In order to enhance the channel mobility, the Si dangling bonds, which were produced during the transformation from the amorphous phase to the poly-crystalline phase of silicon (Si), were reduced by using plasma hydrogenation. Measurements show that the μ FE reached 45 cm 2/V s after passivation by an inductively coupled plasma chemical vapor deposition (ICPCVD) system.