| 摘要 |
In a semiconductor device having a contact structure, a semiconductor element is formed on the surface of a semiconductor substrate and an inter-level insulating film is formed on the entire surface. Then, an insulating film having a high etching selective ratio with respect to the inter-level insulating film is formed on the inter-level insulating film. After this, the thus formed insulating film is etched back and left behind only on the side wall of a stepped portion caused in the inter-level insulating film which defines a contact hole forming area. Then, a contact hole having an upper end portion formed in a forward tapered form is formed in the inter-level insulating film by use of a SAC technique using an insulating film left on the side wall of the stepped portion as the etching stopper. Since the contact hole having an upper end portion formed in a tapered form is formed, the margin for the short circuit between the side wall portion of the contact hole and the semiconductor element can be sufficiently large while the area of the bottom portion of the contact hole can be kept large, and thus the reliability of the semiconductor device can be enhanced.
|
