Degradation of laser-crystallized laterally grown poly-Si TFT under dynamic stress

This letter studies the electrical degradation of laterally grown polycrystalline silicon thin-film transistors (poly-Si TFTs) under dynamic voltage stress. The experimental results show the serious electrical degradation of poly-Si TFTs with a protruding grain boundary. The concentration of the electric field in the protrusion region was verified by capacitance-voltage measurements and simulation of the device characteristics. These results reveal that more electrons are induced at the grain boundary of the poly-Si channel because of the relatively high electric field in the protrusion region. Based on these data, this letter proposes a model to explain the enhanced electrical degradation of poly-Si TFTs with a protruding grain boundary, generated by laser-crystallized lateral growth technique.