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:
Dec. 12, 2000
Filed:
Jun. 18, 1999
Disco Corporation, Tokyo, JP;
Abstract
Disclosed is an improved semiconductor wafer grinding apparatus comprising at least wafer holding means and wafer grinding means. The wafer holding means comprises a holder having a wafer-gripping surface for sucking and holding a selected semiconductor wafer and liquid bearing means for rotatably supporting the holder. The liquid bearing means has inclination control means formed therein, and the inclination control means includes discrete inclination controlling areas for suspending the holder at upper and lower levels. Each inclination controlling area has flow rate control means connected thereto. The parallelism of the wafer-gripping surface relative to the wafer grinding means is assured by controlling the flow rate of the liquid to each inclination controlling area.