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. 11, 1993
Filed:
Nov. 13, 1991
Yujiro Ikeda, Ikoma, JP;
Takao Kinoshita, Tenri, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A method for forming a contact plug comprising steps of depositing on a semiconductor substrate provided with a base device an interlayer insulator consisting of lowermost, intermediate and uppermost layers in which the intermediate layer is less sensitive to an etchant which is capable of dissolving the lowermost layer; subjecting the resultant substrate to a thermal treatment to planarize the surface of the uppermost layer; forming a contact hole by dry-etching at an intended contact region of the interlayer insulator; subjecting the contact hole to wet-etching with an etchant which is capable of dissolving the lowermost layer of the interlayer insulator to form a stepped portion between the edges of the lowermost layer and the intermediate layer in the contact hole; and depositing a metal in the resulting contact hole to form a contact plug, thereby preventing the contact plug from peeling off the substrate.