Inspection device and inspection method for the optical examination of object surfaces, particularly of wafer surfaces
First Claim
1. An inspection device for optical examination of object surfaces, comprising:
- a first illumination device and a second illumination device, for illuminating the object surface, and further having a scattered light detector disposed in a dark field of the first and second illumination devices, which detector is employed to detect light reflected and/or scattered from irregularities in the object surface, wherewith the first illumination device comprises a laser for illuminating a measurement point on the object surface;
wherein 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.
3 Assignments
0 Petitions
Accused Products
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.
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Citations
20 Claims
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1. An inspection device for optical examination of object surfaces, comprising:
- a first illumination device and a second illumination device, for illuminating the object surface, and further having a scattered light detector disposed in a dark field of the first and second illumination devices, which detector is employed to detect light reflected and/or scattered from irregularities in the object surface, wherewith the first illumination device comprises a laser for illuminating a measurement point on the object surface;
wherein 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. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 13, 14, 15, 16, 17, 18, 19, 20)
- a first illumination device and a second illumination device, for illuminating the object surface, and further having a scattered light detector disposed in a dark field of the first and second illumination devices, which detector is employed to detect light reflected and/or scattered from irregularities in the object surface, wherewith the first illumination device comprises a laser for illuminating a measurement point on the object surface;
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10. A method of inspection for optical examination of object surfaces comprising the steps of illuminating the object surface by a first illumination device and a second illumination device, wherewith the first illumination device illuminates a measurement point on the object surface by means of laser illumination, wherewith the light reflected and/or scattered from irregularities on the object surface is detected by means of a “
- scattered light detector”
operating in a dark field of the first and second illumination devices; and
illuminating with the second illumination device illuminates the same measurement point on the object surface as the laser beam, with a larger image spot, using light of lower coherence and lower anisotropy than that of the laser beam. - View Dependent Claims (11, 12)
- scattered light detector”
Specification