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:
Oct. 22, 2002
Filed:
Jun. 08, 1999
Kyoko Egashira, Kyoto, JP;
Koji Eriguchi, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A particular portion of a damaged layer within a semiconductor substrate, which is likely to affect the performance of resulting semiconductor devices, is distinguished from the other negligible portions thereof and the depth of that non-negligible portion is detected. An Si substrate is placed on a stage, and a mercury electrode, which forms a Schottky barrier with the Si substrate, is brought into contact with the surface of the Si substrate. When a constant current is supplied from a constant current source between the mercury electrode and the Si substrate, charges are trapped at the trap centers in the damaged layer within the Si substrate. As a result, a potential on the conduction band rises near the surface of the Si substrate. And if the voltage between the electrode and the substrate is increased along with the potential rise, a constant current flows. By measuring the variation in the saturated voltage with time using a voltmeter, the defect density can be estimated and the depth of only the particular portion of the damaged layer, having impact on the resulting devices, can be detected.