METHOD AND APPARATUS FOR INSPECTING RETICLES IMPLEMENTING PARALLEL PROCESSING

• US 20060269119A1
• Filed: 08/04/2006
• Published: 11/30/2006
• Est. Priority Date: 05/05/1999
• Status: Active Grant

• Current Assignee: KLA-Tencor Corporation
• Original Assignee: KLA-Tencor Corporation
• Inventors: MILLER, LAWRENCE R., JOHNSON, ERIK N., GOLDBERG, EDWARD M.
• Granted Patent: US 7,724,939 B2
• Time in Patent Office: Days
• US Class Current: 382/144
• CPC Class Codes: G01N 2021/95615 with stored comparision signal
• CPC Class Codes: G01N 2021/95676 Masks, reticles, shadow masks
• CPC Class Codes: G01N 21/9501 Semiconductor wafers manufacturing processes per se of semiconductor devices implementing a measuring step H01L22/10
• CPC Class Codes: G01N 21/95607 using a comparative method
• CPC Class Codes: G03F 1/84 Inspecting
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/0006 using a design-rule based approach
• CPC Class Codes: G06T 7/001 using an image reference approach

Abstract

Disclosed is an apparatus for analyzing a plurality of image portions of at least a region of a sample. The apparatus includes a plurality of processors arranged to receive and analyze at least one of the image portions, and the processors being arranged to operate in parallel. The apparatus also includes a data distribution system arranged to receive image data, select at least a first processor for receiving a first image from the image data, select at least a second processor for receiving a second image from the image data, and output the first and second image portions to their selected processors.

Claims

1. An apparatus for inspecting a plurality of image portions of at least a region of a sample for defects, the apparatus comprising:

a plurality of processors arranged to receive and analyze the image portions, the processors being arranged to operate in parallel and being configurable to implement one or more algorithms to determine whether the corresponding regions of the sample are defective, wherein each processor has access to a memory portion sized to hold at least one of the image portions; and

a data distribution system arranged to receive image data, select at least a first processor for receiving a first image portion and not a second image portion of the image data, select at least a second processor for receiving the second image portion and not the first image portion of the image data, and output the first image portion to the memory portion that is accessible by the first processor and the second image portion to the memory portion that is accessible by the second selected processor, wherein the first image portion and the second image portion are different image portions that each has a width that comprises a plurality of pixels and a length that comprises a plurality of pixels, wherein the first processor is then operable to implement one or more algorithms to analyze the first image portion to determine whether the analyzed first image portion has a defect and the second processor is operable to implement one or more algorithms to analyze the second image portion to determine whether the analyzed second image portion has a defect, wherein the defect determination operations for the first and second image portions are each based on analysis of substantially all of the respective image portion.

2. An apparatus as recited in claim 1, wherein the data distribution system is further arranged to divide the image data into a plurality of image portions.

3. An apparatus as recited in claim 1, wherein the first processor is arranged to receive a first reference image portion corresponding to the first image portion and to compare the first image portion to the first reference image portion, and the second processor is arranged to receive a second reference image portion corresponding to the second image portion and to compare the second image portion to the second reference image portion, and wherein determining whether the analyzed first image portion has a defect is based on the comparison between the first image portion and the first reference image portion and determining whether the analyzed second image portion has a defect is based on the comparison between the second image portion and the second reference image portion.

4. An apparatus as recited in claim 1, wherein at least a part of the first image portion is identical to at least part of the second image portion.

5. An apparatus as recited in claim 1, wherein the first processor is configured with a different algorithm for analyzing the first image portion than the second processor.

6. An apparatus for inspecting a plurality of image portions of at least a region of a sample, the apparatus comprising:

a plurality of distributors arranged to receive the image portions; and

a plurality of processors that are arranged into a plurality of subgroups that are each coupled to an associated distributor, wherein each processor has access to a memory portion sized to hold at least one of the image portions, each processor being configurable to implement one or more algorithms for analyzing the image portions to determine whether the corresponding regions of the sample are defective, each distributor being configurable to output selected image portions to its associated subgroup of processors whereby a different set of one or more image portions is output to each associated processor'"'"'s accessible memory portion, at least two of the processors being arranged to analyze at least two of the image portions in parallel, wherein the image portions are different image portions that each has a width that comprises a plurality of pixels and a length that comprises a plurality of pixels, wherein each of the at least two processors are operable to implement one or more algorithms to analyze substantially all of each of its image portions to determine whether the analyzed each image portion has a defect.

7. An apparatus as recited in claim 6 wherein the distributors are arranged in a daisy chain configuration such that a first distributor receives the image portions and outputs one or more of the image portions to a second distributor.

8. An apparatus as recited in claim 6 wherein each subgroup of processors includes a supervisor processor that is coupled with an associated one of the distributors so as to receive the selected image portions from the associated distributor, wherein each supervisor processor is configurable to distribute the selected image portions to selected processors within its associated subgroup.

9. An apparatus as recited in claim 6 wherein a first processor is arranged to receive a selected image portion and a selected reference image portion corresponding to the selected image portion and to compare the selected image portion to the selected reference image portion

10. An apparatus as recited in claim 6, wherein a first processor is arranged to receive a selected image portion and a reference data portion that characterizes a pattern of the sample that the selected image portion corresponds to, the first processor being further arranged to render a reference image portion from the reference data portion and to compare the reference image portion to the selected image portion.

11. A method of inspecting a sample having a plurality of fine patterns thereon, and processing data resulting from the inspection, comprising:

a) receiving data derived from the inspection in a multiprocessor system, the system comprising a master processor and a plurality of slave processors;

b) dividing the data into groups using the master processor and sending a different data group to a different memory portion that is accessible by a different one of the slave processors, each data group corresponding to information derived from a portion of the sample, wherein the data groups are different image portions that each has a width that comprises a plurality of pixels and a length that comprises a plurality of pixels, wherein each slave processor is configurable to implement one or more algorithms for analyzing substantially all its received data group to determine whether the corresponding portion of the sample is defective;

c) processing the data groups with the slave processors based on the one or more algorithms of each slave processor; and

d) deriving defect information regarding the sample and the fine patterns from the combined data.

12. The method of claim 11, wherein the system comprises a plurality of master processors, each in communication with a plurality of slave processors, and wherein each of the master processors is in communication with a central processor, the central processor allocating data among the master processors.

13. The method of claim 11, wherein a first group of the slave processors uses one or more algorithms selected to process data with high accuracy, but at a relatively slow rate, and wherein a second group of the slave processors uses one or more algorithms selected to process data with a relatively low accuracy, but at a high rate.

14. The method of claim 11, where the data groups are processed using an algorithm which compares data derived from differing regions of the sample.

15. The method of claim 11, wherein the data groups are processed using an algorithm which compares data derived from a portion of the sample with data derived from a file used to design the sample.

16. A method for analyzing image data obtained from a sample using a plurality of processors, comprising the acts of:

receiving image data from an inspection system that generates the image data from a sample;

dividing the image data into a plurality of image portions that correspond to various portions of the sample;

outputting each image portion to a memory portion that is accessible by a selected processor, at least some of the image portions being output to different memory portions that are accessible by different processors, each processor being configurable to implement one or more algorithms for analyzing the image portions to determine whether the corresponding portions of the sample are defective, wherein the image portions are different image portions that each has a width that comprises a plurality of pixels and a length that comprises a plurality of pixels;

analyzing substantially all of each image portion for defects within the selected processor based on the selected one or more algorithms for such selected processor to then determine whether the corresponding portion of the each analyzed image portion has a defect; and

outputting and combining results from each processor such that defect data is compiled for the entire image data.

17. A method as recited in claims 16, wherein at least some of the image portions are analyzed with different algorithms.

18. A method as recited in claims 16, wherein at least some of the image portions are analyzed more stringently than others of the image portions.

19. A method as recited in claims 16, further comprising receiving reference data corresponding to each image portion.

20. A method as recited in claims 19, wherein each image portion is analyzed by comparing each image portion to its corresponding reference data.

21. A method as recited in claims 16, further comprising receiving control data that specifies how to divide and output the image portions to their selected processors.

22. A method as recited in claims 21, wherein the control data also specifies how to analyze the image portions for defects within the selected processors.