| 摘要 |
PURPOSE:To increase switching speed applying mobility modulation and obtain high speed devices of a shift register and the like, by changing the local level distribution of a plurality of gate insulating layers which put semiconductor layers having different carrier mobility between them, and applying a gate voltage on one of the gates. CONSTITUTION:On a substrate, the following are formed in order; a first gate electrode 7a, a first gate insulating film 8a being an a-SiNX: H insulating film for example, a C-Si layer 9a to be a semiconductor layer, a source electrode 5 and a drain electrode 6. On these electrodes and a-Si:H layer 9b is formed, and a second gate electrode 7b is arranged via a second gate insulating film 8b. By applying a gate voltage on the first gate electrode 7a or the second gate electrode 7b, switching speed can be increased as the result of the differ ence of carrier mobility in the semiconductor layer. |
