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:
Jan. 07, 1986
Filed:
Oct. 05, 1982
Applicant:
Inventors:
Chusuke Munakata, Nishitama, JP;
Noriaki Honma, Hachioji, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R / ;
U.S. Cl.
CPC ...
3241 / ; 3241 / ;
Abstract
To nondestructively measure the carrier lifetime and cutoff frequency of a semiconductor wafer having a junction, the apparatus of this invention comprises means for radiating a pulsated photo beam whose frequency is changeable to the semiconductor wafer having a junction, means for taking out the resulting photovoltage by capacitance coupling and means for calculating the carrier lifetime and cutoff frequency from the chopping-frequency dependence characteristics of this photovoltage.