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:
Apr. 02, 1996
Filed:
Dec. 04, 1992
Toshinori Maeda, Osaka, JP;
Yukiharu Uraoka, Nara, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A luminescence amount detecting part detects a weak optical radiation which a transistor in a semiconductor integrated circuit emits owing to a hot carrier effect. An output thereof is image-processed by an image processing part. An information storage part stores information on a transistor width and information on a switching frequency at an execution of a test pattern into each transistor. A switching time calculating part evaluates a switching time of the transistor from respective outputs of the image processing part and the information storage part to output a result. Thus the switching time can be evaluated easily without a electron beam tester whose operation is complicated. A delay time can be evaluated by detecting a luminescence amount which changes depending on a gate voltage, instead of measuring a gate voltage.