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. 10, 2013
Filed:
Jan. 20, 2011
Juergen Schwandner, Garching, DE;
Michael Kerstan, Burghausen, DE;
Juergen Schwandner, Garching, DE;
Michael Kerstan, Burghausen, DE;
Siltronic AG, Munich, DE;
Abstract
A method of producing a semiconductor wafer includes a plurality of steps carried out in the following order. Simultaneous double-side material-removal processing is carried out on a semiconductor wafer sliced from a single crystal by processing the semiconductor wafer between two rotating ring-shaped working disks. Each working disk includes first abrasives having an average grain size in a range of 5.0 to 20.0 μm. Both sides of the semiconductor wafer are treated with an alkaline medium. Grinding of the front and rear sides of the semiconductor wafer is carried out. For the grinding of each side a first side is held using a wafer holder and the other side is processed using a grinding tool. The grinding tool includes second abrasives having an average grain size that is smaller than the average grain size of the first abrasives and having an average grain size being in a range of 1.0 to 10.0 μm. Both sides are polished using a polishing pad including third abrasives having an average grain size in a range of 0.1 to 1.0 μm. The front side is polished using a stock removal polishing pad that is free of abrasives and a polishing agent containing fourth abrasives. The front side is then chemical mechanical polished.