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. 05, 2000
Filed:
Apr. 02, 1999
Dale A Witte, O'Fallon, MO (US);
Tracy Ragan, Warrenton, MO (US);
MEMC Electronics Materials, Inc., St. Peters, MO (US);
Abstract
Methods of slicing ingots of semiconductor material into wafers using a wire saw. The wire saw includes a wire that is movable in a forward direction and a reverse direction for slicing the ingots. The methods include defining an identification region of each wafer to be sliced from the ingots and aligning an alignment feature of the ingots in approximately the same position relative to the wire saw for each of the ingots. The identification region of the wafer is adapted for marking with an identification mark after slicing. The methods also include slicing the ingot into wafers with the wire saw. The slicing step includes moving the wire in the forward and reverse directions during slicing except when slicing in the identification region of each wafer and moving the wire only in the forward direction when slicing in the identification region of each wafer. In slicing the ingot into wafers, thickness variations relative to the size of the identification mark are reduced in the identification region.