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:
Feb. 21, 1995
Filed:
Sep. 30, 1992
Anthony Sayka, San Antonio, TX (US);
Stacy W Hall, San Antonio, TX (US);
Judy U Galloway, Fairoaks, TX (US);
Pierre Leroux, San Antonio, TX (US);
Bryan D Schmidt, San Antonio, TX (US);
Daniel D Siems, Boerne, TX (US);
Henry B Taylor, III, San Antonio, TX (US);
Edward R Vokoun, Boerne, TX (US);
VLSI Technology, Inc., San Jose, CA (US);
Abstract
Method and apparatus for detecting the presence of selected types of defects, such as chemical stains from a liquid photoresist material or a liquid dielectric material, on a non-visible chosen surface of a semiconductor water that has undergone at least one processing step. In one embodiment, a support substrate for, the wafer is provided that has a highly reflecting surface adjacent to the chosen surface. The reflecting surface and the chosen surface are moved apart, and the chosen surface is illuminated with light to form an optical image of the chosen surface. The optical image of the chosen surface is reflected in the reflecting surface, and the reflected optical image is examined for the presence of selected types of defects. In another embodiment, a portion of this reflecting surface is initially contiguous to the chosen surface. A selected defect, if any, on the chosen surface changes a surface characteristic of the reflecting surface so that the presence of this defect on the chosen surface is visually perceptible on the reflecting surface.