| 摘要 |
<p>PURPOSE:To prevent the concentration of electric field and the generation of leakage current by forming an action semiconductor which constitutes a channel region of a thin film transistor and an impurity diffusion layer which has a concentration gradient all over the interface between a source electrode and a drain electrode. CONSTITUTION:Two layer films which cover an active semiconductor layer 15 and a gate insulation film 105, are formed on each gap on a processing board where each thin film transistor device is formed thereon. A gate electrode 14 and a protection film 106 are further formed thereon, thereby forming each thin film transistor device. The two layer films for the semiconductor layer 15 and the insulation film 105 are formed based on a CVD process. As the temperature of the substrate at that time is around 250 deg.C, the phosphorous (P) deposited on the surface of a titanium (Ti) film 100 is diffused into the semiconductor layer 15, for example, an alpha-Si layer during the CVD processing, keeping a concentration gradient, thereby forming an impurity diffusion layer 104. The concentration of electric field will be eliminated by forming the impurity diffusion layer 104 all over the interface between the semiconductor layer 15 which constitutes the channel region of the thin film transistor, a source electrode 101, and a drain electrode 102 so that the generation of mark current may be prevented.</p> |
