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. 21, 1991
Filed:
Apr. 21, 1989
Applicant:
Inventors:
Tadashi Nishimura, Hyogo, JP;
Kazukyuki Sugahara, Hyogo, JP;
Shigeru Kusunori, Hyogo, JP;
Akihiko Ohsaki, Hyogo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 40 ; 437 41 ; 437 51 ; 437 52 ; 437 56 ; 437 89 ; 437203 ; 437233 ;
Abstract
A vertical MOS transistor having its channel length determined by the thickness of an insulating layer provided over a semiconductor substrate, rather than by the depth of a trench in which the transistor is formed. As a result, the characteristics of the transistor as relatively unaffected by doping and heat-treatment steps which are performed during formation. Also, the transistor may be formed so as to occupy very little surface area, making it suitable for application in high-density DRAMs.