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:
Aug. 01, 1995
Filed:
May. 12, 1993
Yutaka Kawata, Kobe, JP;
Takuya Kusaka, Kobe, JP;
Hidehisa Hashizume, Miki, JP;
Futoshi Ojima, Kobe, JP;
Kabushiki Kaisha Kobe Seiko Sho, Kobe, JP;
Leo Corporation, Tokyo, JP;
Abstract
An apparatus for measuring the life time of minority carriers includes a light source for irradiating a first region of a semiconductor wafer, a microwave generator for generating microwaves, a transmission line for transmitting a first part of the generated mark raised to the region of the semiconductor wafer that is radiated by the excitation light and a second portion of the generated microwave to a region of the semiconductor wafer that is not radiated by the excitation light. The intensity of the microwave signals reflected from the semiconductor wafer are detected and the life time of the minority carriers is calculated based upon the detected intensities.