A Novel Bottom-Gate Poly-Si Thin Film Transistors with High ON/OFF Current Ratio

ON/OFF 전류비를 향상시킨 새로운 bottom-gate 구조의 다결정 실리콘 박막 트랜지스터

  • Published : 1999.05.01


We have proposed and fabricated the new bottom-gated polycrystalline silicon (poly-Si) thin film transistor (TFT) with a partial amorphous-Si region by employing the selective laser annealing. The channel layer of the proposed TFTs is composed of poly-Si region in the center and a-Si region in the edge. The TEM image shows that the local a-Si region is successfully fabricated by the effective cut out of the incident laser light in the upper a-Si layer. Our experimental results show that the ON/OFF current ratio is increased significantly by more than three orders in the new poly-Si TFT compared with conventional poly-Si TFT. The leakage current is decreased significantly due to the highly resistive a-Si re TFTs while the ON-series resistance of the local a-Si is reduced significantly due to the considerable inducement of electron carriers by the positive gate bias, so that the ON-current is not decreased much.


다결정 실리콘;비정질 실리콘;박막 트랜지스터;레이저 어닐링;Bottom-gate 구조


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