Fabrication and characterization of Schottky barrier polysilicon thin-film transistors with excimer-laser crystallized channel

Schottky barrier thin-film transistors (SB TFT) with field-induced drain (FID) have recently been demonstrated to exhibit ambipolar capability with low off-state leakage current. In this study, we investigate and compare the characteristics of poly-Si SB TFTs with channel layer prepared by excimer laser crystallization (ELC) and solid-phase crystallization (SPC). It is shown that the use of ELC could greatly improve the device characteristics, comparing to the SPC counterparts. Excellent device performance with steep subthreshold slope and on/off current ratio higher than 10⁸ for both p- and n-channel operations are demonstrated on a single device with ELC channel. The effects of sub-gate bias, channel length, and channel offset length, on device characteristics are also explored.