Control of the performance of polysilicon thin-film transistor byhigh-gate-voltage stress

The performance of low-pressure chemical-vapor-deposited (LPCVD) polycrystalline-silicon thin-film transistors (TFTs) can be controlled by applying a high-gate-voltage stress. The potential barrier height at the grain boundary is reduced after positive high-gate-voltage stress and then increases after negative high gate voltage stress. The experimental results indicate that Ca and Al ions or hydrogen atoms existing in the gate oxide may be able to passivate grain boundaries at the polysilicon-SiO₂ interface