Thermally generated leakage current mechanisms of metal-induced laterally crystallized n-type poly-Si TFTs under hot-carrier stress

Mechanisms of thermally generated leakage current have been systematically studied for metal-induced laterally crystallized n-type polycrystalline silicon thin film transistors under the hot-carrier stress. Various mechanisms of thermally generated leakage current are identified by both forward and reverse modes. The decrease of thermally generated leakage current is attributed to the depletion region modulation effect, which results from its shrinkage. While the increase of thermally generated leakage current is caused by the increase of the donor trap density, its increment relative to the initial one follows the Schottky model in the forward mode. Overall, the depletion region modulation effect dominates and the thermally generated leakage current decreases.

► The TG leakage current under the HC stress decreases due to the ‘‘DRME” mechanism.
► The TG leakage current under the HC stress increases due to the “TIE” mechanism.
► The larger the stress-Vd or TFTs’ size is, the easier the “DRME” occurs.
► The increment of the TG leakage current follows the Schottky model.
► The ‘‘DRME” is the dominant mechanism in the TG leakage current under the HC stress.