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:
May. 25, 2010
Filed:
Aug. 01, 2007
Hung-chin Guthrie, Saratoga, CA (US);
Ming Jiang, San Jose, CA (US);
Yeak-chong Wong, San Jose, CA (US);
Hung-Chin Guthrie, Saratoga, CA (US);
Ming Jiang, San Jose, CA (US);
Yeak-Chong Wong, San Jose, CA (US);
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
During planarization of wafers, the thickness of a layer of a wafer is measured at a number of locations, after the wafer has been planarized by chemical mechanical polishing. The thickness measurements are used to automatically determine, from a center to edge profile model to which the measurements are fit, a parameter that controls chemical mechanical polishing, called 'backside pressure.' Backside pressure is determined in some embodiments by a logic test based on the center-to-edge profile model, coefficient of determination R-square of the model, and current value of backside pressure. Note that a 'backside pressure' set point is adjusted only if the fit of the measurements to the model is good, e.g. as indicated by R-square being greater than a predetermined limit. Next, the backside pressure that has been determined from the model is used in planarizing a subsequent wafer.