| 摘要 |
PURPOSE:To increase the boundary level density of an active layer and obtain a TFT with high speed operation by a method wherein a source electrode and a drain electrode are provided on an insulating substrate and an amorphous Si active layer is formed over the whole substrate surface including the source and drain electrodes by glow discharge decomposition and a gate insulating film is formed on the active layer by employing glow discharge gas containing O2. CONSTITUTION:A source electrode 8 and a drain electrode 9, which are made of Cr, Al or the like and whose surfaces are covered with P-type impurity doped amorphous Si layers 3 are provided on an insulating substrate 1 and an amorphous Si active layer 4 is formed over the whole substrate 1 surface including the electrodes 8 and 9 by a glow discharge decomposition method with mixed gas containing SiH4. Then a gate SiO2 insulating layer 5 is formed on the surface of the active layer 4 by the same glow discharge decomposition method. At that time, the mixed gas containing SiH4 is replaced by N2 containing O2 and the surface 10 of the layer 4 is subjected to plasma oxidation and the insulating layer 5 is formed by the glow discharge decomposition method. With this constitution, a film which has high boundary level density between the layer 4 and itself can be obtained without employing a CVD method and a metal gate electrode 7 is formed on that film. |
