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. 22, 2000
Filed:
Aug. 25, 1998
Ray Lee, Taipei, TW;
Shih-Po Lin, Taipei Hsien, TW;
Jim Ho, Hsinchu, TW;
Ming-Hong Lin, Kaohsiung Hsien, TW;
Abstract
A clamp affixes a wafer by entirely covering the edge of the wafer, wherein the radius of the inner surface of the clamp is about 1 mm shorter than the radius of the wafer. Besides, there are four pairs of square protuberances distributed even along the inner surface of the clamp for affixing the wafer, wherein the square protuberances only hold the edge of the device regions of the wafer. Even though the wafer is slightly off position, the square protuberances are still able to affix the wafer properly. In addition, the lifetime of the clamp of the invention is about 100 hours, which is two times of a conventional clamp, so that the cost is reduced.