| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a TFT element with a high energy gap off set layer structure which can improve quality of LCD screen. SOLUTION: An effect to improve screen quality of an LCD greatly is obtained by raising ON/OFF current ratio of an element by providing a TFT element (hereinafter abbreviated to an upper gate electrode TFT element) with a low-high energy gap semiconductor layer structure and a gate electrode 10 in an upper layer, making a low energy gap semiconductor layer a channel layer 30 of conduction carrier, preventing tunnel phenomenon from energy band wherein conduction carrier is generated to energy band by a high energy gap off-set layer, and reducing gate induced drain leakage current.</p> |
