Suppression of leakage current of low-temperature polycrystalline silicon thin-film transistors by negative bias sweeping

Reduction in the off-state leakage current of p-type low-temperature polycrystalline silicon (poly-Si) thin-film transistors (TFTs) after negative bias sweeping is observed and reported in this paper. It is found that the subthreshold and on-state characteristics of poly-Si TFTs are almost unaffected. Electron trapping locally in the gate oxide near the drain during negative biasing is proposed to be the underlying mechanism. The most effective bias for leakage current suppression locates in the region that kink effect occurs.