Projection and distance segmentation algorithm for wafer defect detection

1. A system comprising:

a light source that generates light;

a stage configured to hold a wafer;

a detector that receives the light reflected from the wafer; and

a processor in electronic communication with the detector, wherein the processor is configured to:

determine a projection in a region of an image that is generated from data from the detector, wherein the projection is an X projection in an X direction and/or a Y projection in a Y direction, and wherein the X direction and the Y direction are perpendicular;

apply at least one threshold to the projection thereby forming at least one segment in the region of the image; and

determine at least one fine segment in the region using at least one distance value from the projection.

2. The system of claim 1 , wherein the light source is a laser.

3. The system of claim 1 , wherein the fine segments are defined along the X direction or the Y direction.

4. The system of claim 1 , wherein the fine segments are defined along the X direction and the Y direction.

5. The system of claim 1 , wherein the processor is further configured to perform defect detection in one or more of the fine segments.

6. The system of claim 1 , wherein the image is a 2D image and wherein the projection converts the 2D image into 1D data.

7. The system of claim 1 , wherein the fine segment is at least five pixels in dimension.

8. A method comprising:

determining a projection in a region of an image of a semiconductor wafer using a processor, wherein the projection is an X projection in an X direction and/or a Y projection in a Y direction, and wherein the X direction and the Y direction are perpendicular;

applying at least one threshold to the projection using the processor thereby forming at least one segment in the region of the image; and

determining, using the processor, at least one fine segment in the region using at least one distance value from the projection.

9. The method of claim 8 , wherein the fine segments are defined along the X direction or the Y direction.

10. The method of claim 8 , wherein the fine segments are defined along the X direction and the Y direction.

11. The method of claim 8 , wherein the method further comprises performing defect detection in one or more of the fine segments.

12. The method of claim 8 , wherein the image is a 2D image and wherein the projection converts the 2D image into 1D data.

13. The method of claim 8 , wherein the fine segment is at least five pixels in dimension.

14. A non-transitory computer-readable storage medium, comprising one or more programs for executing the following steps on one or more computing devices:

determine a projection in a region of an image of a semiconductor wafer, wherein the projection is an X projection in an X direction and/or a Y projection in a Y direction, and wherein the X direction and the Y direction are perpendicular;

apply at least one threshold to the projection thereby forming at least one segment in the region of the image; and

determine at least one fine segment in the region using at least one distance value from the projection.

15. The non-transitory computer-readable storage medium of claim 14 , wherein the fine segments are defined along the X direction or the Y direction.

16. The non-transitory computer-readable storage medium of claim 14 , wherein the fine segments are defined along the X direction and the Y direction.

17. The non-transitory computer-readable storage medium of claim 14 , wherein the steps further include performing defect detection in one or more of the fine segments.

18. The non-transitory computer-readable storage medium of claim 14 , wherein the image is a 2D image and wherein the projection converts the 2D image into 1D data.

19. The non-transitory computer-readable storage medium of claim 14 , wherein the fine segment is at least five pixels in dimension.