| 摘要 |
PURPOSE:To form a wiring layer on a substrate with a connecting window in fine size with an excellent step coverage by interposing a polycrystalline Si layer, to which an impurity is doped, in the connecting window when a diffusion region is formed to the semiconductor substrate, the whole surface containing the diffusion region is coated with an insulating film and the connecting window is bored while the wiring layer being in contact with the diffusion region is formed. CONSTITUTION:An N<+> type diffusion region 12 is formed to a semiconductor substrate 11, the whole surface containing the diffusion region 12 is coated with a PSG film 13, and a fine connecting window 14 in approximately 1.3mum square is bored to the film 13 while being made to correspond to one part of the region 12. A polycrystalline Si layer 15 is grown on the whole surface while burying the window 14, and a resist film 16 is shaped on the layer 15 while flattening the surface. The film 16 and the layer 15 are removed through etching at approximately the same speed by using CF4 and O2 gas, the mixing ratio thereof is brought to approximately 20:1, the surface of the film 13 is exposed, the film 16 slightly intruding into the window 14 is incinerated and removed by using O2 gas, P is deped to the residual layer 15 to change the layer 15 into a conductive layer 17, and an Al wiring layer 18 is applied. |
