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:
Nov. 12, 2013
Filed:
Jul. 27, 2007
Kiyoshi Mori, San Antonio, TX (US);
Shu Ikeda, Austin, TX (US);
Gabriel Gebara, Austin, TX (US);
Abound Limited, Menlo Park, CA (US);
Abstract
Systems and methods for detecting watermark formations on semiconductor wafers are described. In one embodiment, a method comprises providing a semiconductor wafer having at least one watermark sensitive region fabricated thereon, subjecting the wafer to a wet processing step, enhancing a susceptibility to detection of at least one watermark formation created on the at least one watermark sensitive region, and detecting the at least one watermark formation. In another embodiment, a method comprises growing a first oxide layer on a surface of a semiconductor wafer, patterning a watermark sensitive structure on the first oxide layer, depositing a silicon layer over the first oxide layer, doping a region of the silicon layer over the watermark sensitive structure with an impurity to create a watermark sensitive region that is prone to retaining watermark formations as result of a wet processing step, and growing a second oxide layer over the silicon layer.