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:
Sep. 09, 1997
Filed:
Sep. 04, 1996
Applicant:
Inventor:
Peter Henry Renteln, Sunnyvale, CA (US);
Assignee:
National Semiconductor Corporation, Santa Clara, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B24B / ;
U.S. Cl.
CPC ...
451 21 ; 451-5 ; 451 41 ; 451 56 ; 451287 ; 451443 ; 451444 ;
Abstract
A method and apparatus for determining the amount of conditioning required to be applied to a polishing pad to achieve a desired removal rate during the polishing of a semiconductor wafer utilizes a rotating conditioning wheel in contact with a rotating polishing pad. Preselected points on just polished wafers are measured for removal rate and such measurements are used to calculate the removal rate as a function of wafer radius. When the removal rate changes by a preselected amount, the polishing pad is conditioned in accordance with the calculations.