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. 01, 1992
Filed:
Jun. 05, 1990
Helene Prigge, Chatswoof, AU;
Josef Lang, Burghausen, DE;
Wacker-Chemitronic Gesellschaft fur Elektronik-Grundstoffe mbH, Burghausen, DE;
Abstract
In the chemo-mechanical polishing, in particular, of semiconductor wafers, he abrasion and the geometrical quality of the wafers decreases with increasing service life of the polishing cloth. This can be prevented by treating the polishing cloth in each case after the polishing operation in a manner such that a pressure field is impressed, essentially without mechanical stress, on the polishing cloth, which pressure field causes a treatment liquid to flow through the interior of the polishing cloth and in this process the residues produced during polishing are rendered mobile and removed. A baseplate placed transversely across the polishing cloth and having a flat working surface provided with exit openings for the treatment liquid is suitable for carrying out the process. In the treatment, the treatment liquid is forced beneath the baseplate into the moving polishing cloth so that the latter is gradually traversed by the zone through which flow takes place.