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. 14, 1994
Filed:
Oct. 21, 1993
Applicant:
Inventors:
Yoshiro Baba, Yokohama, JP;
Satoshi Yanagiya, Kawasaki, JP;
Noburo Matsuda, Kawasaki, JP;
Shunichi Hiraki, Nagareyama, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Primary Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ;
U.S. Cl.
CPC ...
257331 ; 257334 ;
Abstract
A vertical MOSFET includes a trench whose inner surface is covered with an insulating layer having a multilayer structure. In order to reduce a change in a gate threshold voltage, and equivalent silicon dioxide thickness of the gate insulating layer and a radius of curvature of an upper corner of the trench are provided such that a dielectric breakdown electric field strength of the gate insulating layer at the upper corner is in the range of 2.5 MV/cm to 5.0 MV/cm.