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:
Mar. 06, 2001
Filed:
Aug. 13, 1999
Hideaki Minami, Annaka, JP;
Super Silicon Crystal Research Institute Corp., Annaka, JP;
Abstract
A pair of ring-shaped lapping plates,are faced to both surfaces of a wafer,. Each lapping plate,has an outer diameter approximately equal to a radius of the wafer,and a lapping surface,sliding in contact with the wafer,. Each lapping plate,is rotated along a direction reverse from the other, while an abrasion slurry A is fed into cavities,of the lapping plates,and discharged together with dusts separated from the wafer,through grooves engraved in the lapping surfaces,and gaps between the wafer,and the lapping surfaces,. The lapping plate,is carried toward the stationary lapping plate,at a rate corresponding to abrasion of the lapping surfaces,. During lapping, the wafer,is rotated by drive rollers,and supported by guide rollers,. In this way, both surfaces of the wafer,are simultaneously lapped.