| US 7,477,371 B2 | ||
| Process and assembly for non-destructive surface inspections | ||
| Norbert Marxer, Schaanwald (Liechtenstein); Kenneth P. Gross, San Carlos, Calif. (US); Hubert Altendorfer, Redwood Shores, Calif. (US); and George Kren, Los Altos, Calif. (US) | ||
| Assigned to KLA-Tencor Corporation, Milpitas, Calif. (US) | ||
| Filed on Aug. 15, 2006, as Appl. No. 11/464,766. | ||
| Application 11/464766 is a division of application No. 10/619109, filed on Jul. 10, 2003, granted, now 7,102,744. | ||
| Application 10/619109 is a continuation of application No. 09/901998, filed on Jul. 10, 2001, granted, now 6,606,153. | ||
| Application 09/901998 is a continuation of application No. 08/770491, filed on Dec. 20, 1996, granted, now 6,271,916. | ||
| Application 08/770491 is a continuation in part of application No. 08/533632, filed on Sep. 25, 1995, abandoned. | ||
| Application 08/533632 is a continuation in part of application No. 08/216834, filed on Mar. 24, 2004, abandoned. | ||
| Prior Publication US 2007/0103676 A1, May 10, 2007 | ||
| This patent is subject to a terminal disclaimer. | ||
| Int. Cl. G01N 21/00 (2006.01) | ||
| U.S. Cl. 356—237.2 [356/237.1] | 48 Claims |
| 1. An optical system for detecting contaminants and defects of a test surface comprising:
a device providing a polarized light beam along a path at an oblique angle to the test surface, producing an illuminated spot
thereon;
a first and a second detector;
a first collector having an optical axis substantially along a line perpendicular to the test surface, said first collector
collecting light from the polarized light beam scattered by the illuminated spot of the surface and conveying the collected
light to the first detector, causing the first detector to provide a single output in response to the light collected by the
first collector; and
a second collector collecting light from the polarized light beam scattered by the illuminated spot of the surface and conveying
the collected light to the second detector, causing the second collector to provide a single output in response to the light
collected by the second collector, wherein the first and second collectors collect light scattered by the surface within different
ranges of collection angles from the line.
|