CHARACTERISTICS OF NEW POLY-SI THIN-FILM-TRANSISTOR WITH A-SI CHANNELREGION NEAR THE SOURCE DRAIN/

We propose the new poly-Si TFT structure which reduces the leakage cur rent effectively employing highly resistive a-Si region in the channel . This new device has selectively crystallized active layer, where bot h edges of channel region adjacent to source and drain are not crystal lized and remain a-Si. In the proposed device, the amorphous silicon r egion behaves like an offset to reduce the leakage current and also ac ts as the conduction channel of carriers under the ON state, so that t he ON-current can be maintained. The experimental results show that th e ON/OFF current ratio of proposed device is 2.71 x 10(6) while that o f conventional one is 2.67 x 10(5). In the fabrication of the proposed device, there are not any additional photomasking steps and mis-align problem.