| 摘要 |
PURPOSE:To improve the yield by preventing the disconnection at the part of a contact hole on a diffused region by a method wherein the diameter of the part of an aperture is widened by making the etching speed for the second insulation film much higher than that for the first one. CONSTITUTION:The first and second insulation film 25 and 26 are successively deposited over the entire surface of a P type Si substrate 21, and the insulation film is flatted by using dry etching technique. Next, contact holes 200 and 201 are formed at the parts corresponding to the source or drain region 24 and the first wiring layer 23 by means of a photoresist 27. Then, using such an etching condition that the ratio of the etching speed for the second insulation film 26 to that for the first one 25 becomes 5 or more, said film 26 of the contact holes 200 and 201 is selectively etched, thereby widening the diameter of the contact hole of said film 26 approx. 1.3-2 times as much as before etching. After removing the photoresist 27, the second wiring layer 28 made of Al is formed. |
