Characteristics and reliability of a polysilicon thin-film transistor with a multi-trenched body

Abstract

This paper describes a polysilicon thin-film transistor (TFT) with a multi-trenched body that has been fabricated and found to suppress the off-state leakage current without degrading the on-state current or other electric properties. The thin-film structure minimizes carrier scattering through the polysilicon's grain-boundary traps. In addition to this effect, our multi-trenched structure reduces the off-state current by 50% compared to a conventional TFT. The effects of high temperature and dc hot-carrier stress are also measured in comparison to a conventional TFT. At 100 • C, the multi-trenched-body TFT has a higher output saturation current. After 10 000 s of stress testing, the trench-bodied structure continues to outperform the conventional TFT.