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:
Feb. 27, 1990
Filed:
Nov. 07, 1988
Applicant:
Inventor:
Yoshio Hirai, Tokyo, JP;
Assignee:
Seiko Instruments Inc., , JP;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R / ;
U.S. Cl.
CPC ...
324551 ; 324554 ;
Abstract
A test method is used for examining a sample insulating film to determine an expected value of time for the sample insulating film to undergo dielectric breakdown. A varying electric stress is applied to a sample insulating film to flow therethrough a varying electric current. The varying electric current is monitored until catastrophic dielectric breakdown occurs in the sample insulating film to measure a critical electric current which flows through the sample insulating film immediately before the breakdown occurs. The expected value of time to breakdown is determined according to the measured critical electric current.