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. 08, 1986
Filed:
Jan. 31, 1984
Noriaki Honma, Nishitama, JP;
Chusuke Munakata, Nishitama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A carrier lifetime measuring apparatus according to the present invention has a construction wherein a first photon beam of a wavelength capable of rendering the optical absorption coefficient of a semiconductor sample very small when the semiconductor sample having a potential barrier in the vicinity of its surface is irradiated with the radiation, and a second photon beam of a wavelength capable of rendering the optical absorption coefficient very large are respectively chopped to alternately irradiate the identical place of the semiconductor sample with the chopped beams; first and second photovoltages which are generated in the semiconductor sample by these photon beams are detected by capacitance coupling; and the ratio between a first amplitude variation and a second amplitude variation is obtained from the amplitudes of the detected photovoltages; thereby to evaluate a minority carrier lifetime in the semiconductor sample.