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:
Nov. 30, 1999
Filed:
Jan. 15, 1998
Takashi Ide, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A wafer defect detection apparatus includes a moving device for moving the wafer in a parallel direction to the wafer's surface, a light-emitting device for emitting an incident light on the surface of the wafer, a light-receiving device for receiving a reflected light reflected by the (111) crystal plane of the wafer, and a rotating device for rotating the wafer with respect to a line perpendicular to the wafer surface as a rotation axis, the [001] direction of the wafer being parallel to the normal line direction of the surface of the wafer. The light-emitting device is arranged in the direction tilted by (57.7.degree.-.alpha.) from the rotation axis and the incident light impinges on the position where the rotation axis intersects the surface of the wafer. The light-receiving device is arranged in the direction tilted by (54.7.degree.+.alpha.) in the direction same as that of the light-emitting device from the rotation axis, and the value of .alpha. is -35.3.degree. to 35.3.degree. excluding 0.degree..
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile