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US 2006/0187446 A1Published application
Highly sensitive defect detection method
AssigneeProMOS Technologies Inc.
InventorsChung-I Chang, Ferris Liu
Life of this patent
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Abstract
A highly sensitive defect detection method is disclosed. A medium with a refractive index greater than 1 is formed on a sample. As a result, incident light projected by a defect detecting system attenuates less when reaching the bottom defects. The detection sensitivity of the defect detecting system is enhanced accordingly.
Claims18
A highly sensitive defect detection method, comprising the steps of:
- providing a substrate having a plurality of device patterns;
- covering a medium on the substrate and between the device patterns, wherein the medium has a refractive index greater than 1;
- projecting a beam of light on the substrate for the light to penetrate through the medium and reach the bottom of the device patterns;
- using a plurality of detectors to receive reflected light from the surface of the substrate and scattered light from the bottom of the device patterns;
- and
- analyzing the signals of the reflected and scattered light to identify a defect distribution on the substrate.
3 more elements
A highly sensitive defect detection method, comprising the steps of:
- covering a medium on a substrate having a plurality of device patterns, wherein the refractive index of the medium is greater than 1 and smaller than sin θ/sin [cot−1(h/d)] where θ is the incident angle of an incident beam, h is the height of the device patterns, and d is the pitch between the device patterns, wherein a ratio of the height to the pitch of the device patterns is greater than 3;
- projecting a beam of light on the substrate for the light to penetrate through the medium and reach the bottom of the device patterns;
- using at least a detector to receive reflected light from the surface of the substrate and scattered light from the bottom of the device patterns;
- and
- comparing the signals of the reflected light and the scattered light from the consecutive device patterns to identify a defect distribution on the substrate.
2 more elements
Dependencies are inferred from the claim text.