Inspection device and inspection method for the optical examination of object surfaces, particularly of wafer surfaces
US8289509B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 27, 2010 |
| Grant date | Oct 16, 2012 |
| Priority date | — |
| Expiry date | Feb 3, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/4735
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An inspection device and a method of inspection, for optical examination of object surfaces, particularly wafer surfaces, wherein the object surface is illuminated by a first illumination device and a second illumination device, wherewith the light reflected and/or scattered from irregularities on the object surface is detected by means of a “scattered light detector” operating in the dark field of the first and second illumination devices, and wherewith the object surface is illuminated by a first illumination device and a second illumination device, wherewith the first illumination device has a laser for illuminating a measurement point on the object surface. The second illumination device is disposed (and oriented) to illuminate the same measurement point on the object surface but with a larger image spot, with the use of light of lower coherence and/or with less anisotropy than that of the laser.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.