Inspection method
A method for inspecting flat objects, especially wafers, comprising the steps of scanning a digital image of the object surface; detecting defects on the object surface; generating a binary image of the scanned image where only detected defects are represented; and compressing the binary image; and wherein detected defects are enlarged before compressing by adding additional, adjacent image points to the image points of the defects. It may be advantageous if only defects having a selected size, shape or position are enlarged.
1. A method for inspecting flat objects, especially wafers, having an object surface, the method comprising the steps of:
(a) scanning a digital image of said object surface;
(b) detecting defects on said object surface;
(c) generating a binary image of said scanned digital image where only detected defects are represented; and
(d) compressing said binary image; wherein
(e) detected defects are enlarged before compressing by adding additional, adjacent image points to said image points of said defects.
2. A method according to claim 1 , and wherein only defects having a selected size, shape or position are enlarged.
3. A method according to claim 2 , and wherein defects are detected by comparing said scanned digital image with a digital reference image.
4. A method according to claim 3 , and wherein said scanned digital image is stored or transmitted in portions, where only such portions are selected where defects have been detected and which are important for further processing of said object surface.
5. A method according to claim 2 , and wherein said scanned digital image is stored or transmitted in portions, where only such portions are selected where defects have been detected and which are important for further processing of said object surface.
6. A method according to claim 1 , and wherein defects are detected by comparing said scanned digital image with a digital reference image.
7. A method according to claim 6 , and wherein said scanned digital image is stored or transmitted in portions, where only such portions are selected where defects have been detected and which are important for further processing of said object surface.
8. A method according to claim 1 , and wherein said scanned digital image is stored or transmitted in portions, where only such portions are selected where defects have been detected and which are important for further processing of said object surface.
9. A method according to claim 6 , and wherein said scanned digital image is stored and transmitted in portions, where only such portions are selected where defects have been detected and which are important for further processing of said object surface.
10. A method according to claim 3 , and wherein said scanned digital image is stored and transmitted in portions, where only such portions are selected where defects have been detected and which are important for further processing of said object surface.
11. A method according to claim 2 , and wherein said scanned digital image is stored and transmitted in portions, where only such portions are selected where defects have been detected and which are important for further processing of said object surface.
12. A method according to claim 1 , and wherein said scanned digital image is stored and transmitted in portions, where only such portions are selected where defects have been detected and which are important for further processing of said object surface.