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. 15, 2001
Filed:
Oct. 26, 1995
Applicant:
Inventors:
Naoyuki Kofuji, Kunitachi, JP;
Shin Arai, Kodaira, JP;
Kazunori Tsujimoto, Higashiyamato, JP;
Tatsumi Mizutani, Koganei, JP;
Keizo Suzuki, Kodaira, JP;
Kenichi Mizuishi, Hachioji, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 2/1302 ;
U.S. Cl.
CPC ...
H01L 2/1302 ;
Abstract
A pulse voltage of duty ratio 5% or below and repetition frequency 400 KHz or above is supplied in order to suppress the notch, charge build-up damage, subtrench and bowing due to the electron shading phenomenon. Thus, a cycle for accelerating electrons occurs in the substrate bias, so that the electron shading phenomenon does not occur.