The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 07, 1996
Filed:
Mar. 15, 1995
Hitoshi Tsuji, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A novolak-based resist layer is formed on an interlayer insulating film, and that portion of the resist layer which is left as a resist mask for a wiring layer groove is formed by the first exposure and the heat treatment in an ammonia atmosphere. Thus, the solution rate of that portion of the resist layer is rendered low with regard to the alkali developing solution. Subsequently, the resist layer is exposed and developed in a regular manner to form a resist mask for defining a contact hole. With the obtained resist pattern used as a mask, the interlayer insulating film is etched to a depth which equals to a length of a contact hole in the depth direction formed at a later step. After that, with use of the resist pattern whose solution rate with respect to the alkali developing solution has been made low as a mask, the wiring layer groove is formed. With the method, a mask resist pattern used for defining a contact hole can be formed in a predetermined region, even if the exposure of the resist layer is displaced from the position where it should have been. Further, no step portion is created between the contact hole and the wiring groove.