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. 11, 2003
Filed:
Jan. 09, 1998
Ronald J. Nagahara, San Jose, CA (US);
Dawn M. Lee, Morgan Hill, CA (US);
LSI Logic Corporation, Milpitas, CA (US);
Abstract
Methods and apparatus for planarizing the surface of a semiconductor wafer by applying non-uniform pressure distributions across the back side of the wafer are disclosed. According to one aspect of the present invention, a chemical mechanical polishing apparatus for polishing a first surface of a semiconductor wafer includes a polishing pad which polishes the first surface of the semiconductor wafer. The apparatus also includes a first mechanism which is used to hold, or otherwise support, the wafer during polishing, and a second mechanism that is used to apply a non-uniform pressure distribution through the first mechanism, directly onto a second surface of the wafer. The second mechanism is further used to facilitate polishing the first surface of the semiconductor wafer such that the first surface of the semiconductor wafer is evenly polished. In one embodiment, the second mechanism is arranged to apply both positive pressure and negative pressure substantially simultaneously across the second surface of the semiconductor wafer.