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:
Jun. 19, 1990
Filed:
Mar. 01, 1989
Yoshiaki Toyoshima, Matsudo, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
The invention provides a semiconductor device and manufacturing method therefor which comprises: a semiconductor substrate of a first conductivity type, source and drain regions of a second conductivity type provided on the surface of the substrate in a mutually electrically isolated arrangement, and a gate electrode provided on the surface of the substrate on the other side of an insulating film and the substrate surface including a channel region between these aforementioned regions; at least the drain region, of which the source and drain regions, consisting of: a first impurity diffusion region provided on the substrate surface in the vicinity of the end portion of the gate electrode; a second impurity diffusion region more highly doped than the first impurity diffusion region and provided in at least a portion of the surface of the aforementioned diffusion region adjacent the end portion of this first impurity diffusion region; and a third impurity diffusion region more highly doped than the second impurity diffusion region and provided on the substrate surface adjacent to the end portion of this second impurity diffusion region.