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:
Oct. 10, 1995
Filed:
Nov. 24, 1993
Seiji Hirade, Hamamatsu, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
A field insulating film and a gate insulating film are formed on the surface of a semiconductor substrate, and thereafter contact holes for a source and drain are formed in the gate insulating film. Polycrystalline Si containing impurities are deposited on the substrate and patterned to form source, gate, and drain electrode layers. The source and drain regions are formed by implanting impurity ions and doping the impurities in the source and drain electrode layers to the substrate surface. An interlayer insulating film having a flat surface is thereafter formed on the substrate, and contact holes are formed in the interlayer insulating film by selective etching. The etching depths of the contact holes are generally the same, preventing an excessive etching of the contact hole for the gate electrode.