| 摘要 |
<p>PURPOSE:To enable a TFT high in mobility and low in leakage current to be easily mass-produced by a method wherein at least the active layer of one of P-channel type polysilicon thin film transistors is set smaller in oxygen or nitrogen concentration than a specific value, and those of the other transistors are set larger than the specific value. CONSTITUTION:A base oxide film 102 is deposited on a substrate 101, an N-type region 114 and P-type regions 113 and 115 are formed thereon, and active layers 116, 117, and 118 are formed at the same time. The active layers 116 and 117 are set smaller than 10<18>cm<-3> in oxygen or nitrogen concentration, and on the other hand, the active layer 118 is set above 10<18>cm<-3> in oxygen or nitrogen concentration. By this setup, TFTs of two kinds, one high in mobility and the other high in leakage current, can be separately mass-produced with ease by minimally changing manufacturing processes.</p> |
