System and method for providing defect printability analysis of photolithographic masks with job-based automation

• US 7,093,229 B2
• Filed: 07/11/2003
• Issued: 08/15/2006
• Est. Priority Date: 09/17/1997
• Status: Expired due to Term

• Current Assignee: Synopsys Merger Holdings LLC (Synopsys Incorporated)
• Original Assignee: Synopsys Incorporated
• Inventors: Pang, Linyong, Chang, Fang-Cheng
• Primary Examiner(s): Siek, Vuthe
• Application Number:
  US10/618,816
• Publication Number:
  US 20040015808A1
• Time in Patent Office: 1,131 Days
• Field of Search: 716 4- 6, 716 19- 21, 703/13, 702/59, 702/81, 430/5, 382/144, 382/145, 382/149
• US Class Current: 716/52
• CPC Class Codes: G03F 1/84 Inspecting

Abstract

Serious defects on a mask can compromise the functionality of the integrated circuits formed on the wafer. Nuisance defects, which do not affect the functionality, waste expensive resources. A defect analysis tool with job-based automation can accurately and efficiently determine defect printability. This tool can run a job, using a mask file, to simulate the wafer exposure that the mask would provide under a given set of parameters. These parameters can relate to the mask itself, the inspection system used to create the mask file, and the stepper that can be used to expose the mask. The processes performed during the job can be done uniformly for defects on the mask. This uniformity allows the tool to efficiently run multiple jobs. The results of the job can be presented using different levels of detail to facilitate user review.

Claims

1. A method of analyzing a mask for use in photolithography, the method comprising:

loading a mask file into a defect analysis tool;

specifying a job to be run using the mask file, wherein the job defines parameters used in processes performed uniformly for defects on the mask, the parameters including settings relating to the mask, an inspection system that provided information for the mask file, and a stepper that can be used in exposing the mask during photolithography;

managing and distributing the job to computation resources;

running the job using the mask file and defined parameters on the computation resources; and

outputting results of the job from the computation resources, wherein the results include printability results for the defects on the mask.

2. The method of claim 1, wherein the mask file includes a standard mask format file (MFF).

3. The method of claim 2, further including converting mask data into the standard MFF.

4. The method of claim 1, wherein the settings include at least one of mask type, phase of the mask, and transmission of the mask.

5. The method of claim 1, wherein the settings include at least one of an inspection system vendor and an inspection system model.

6. The method of claim 1, wherein the settings include at least one of wavelength, numerical aperture, reduction, defocus, and illumination.

7. The method of claim 1, wherein managing and distributing the job is performed by a job manager.

8. The method of claim 7, wherein the job manager allows multiple jobs to be run in parallel.

9. The method of claim 7, wherein the job manager schedules multiple computation resources to run one or more jobs.

10. The method of claim 1, wherein the results include multiple levels for user review.

11. The method of claim 10, wherein one level includes an overall summary of simulations performed on the defects.

12. The method of claim 11, wherein the overall summary includes defect scoring of the defects.

13. The method of claim 10, wherein one level includes a defect map of the defects on the mask.

14. The method of claim 13, wherein the defect map is color-coded based on a defect severity associated with each defect.

15. The method of claim 14, wherein a high defect severity is indicated by a flashing light.

16. The method of claim 10, wherein one level can provide an aerial image of each defect and a reference image of an area corresponding to that of the defect.

17. The method of claim 1, further comprising:

entering a status for each defect based on a user'"'"'s review of the results of the job.

18. The method of claim 17, further comprising:

providing a history of statuses for each defect based on users'"'"' reviews of the results of the job.

19. The method of claim 1, further comprising:

accessing the results of the job using a web browser.

20. A system for analyzing a mask for use in photolithography, the system comprising:

an application server for running a defect analysis tool;

means for loading a mask file into the defect analysis tool;

means for specifying a job to be run using the mask file, wherein the job defines parameters used in processes performed uniformly for defects on the mask, the parameters including settings relating to the mask, an inspection system that provided information for the mask file, and a stepper that can be used in exposing the mask during photolithography;

computation resources for running the job;

a job manager for distributing the job to the computation resources and receiving results of the job from the computation resources; and

means for outputting results of the job, wherein the results include printability results for the defects on the mask.

21. The system of claim 20, further including means for converting mask data into a standard mask format file (MFF).

22. The system of claim 20, wherein the settings include at least one of mask type, phase of the mask, and transmission of the mask.

23. The system of claim 20, wherein the settings include at least one of an inspection system vendor and an inspection system model.

24. The system of claim 20, wherein the settings include at least one of wavelength, numerical aperture, reduction, defocus, and illumination.

25. The system of claim 20, further including storage for storing at least one of the parameters and the results of the job.

26. The system of claim 20, wherein the job manager includes means for allowing multiple jobs to be run in parallel.

27. The system of claim 26, wherein the job manager includes means for scheduling multiple computation resources to run one or more jobs.

28. The system of claim 20, wherein the means for outputting results includes means for accessing the results via multiple review levels.

29. The system of claim 28, wherein at least one review level includes an overall summary of simulations performed on the defects.

30. The system of claim 29, wherein at least one review level includes a defect map of the defects on the mask.

31. The system of claim 30, wherein the means for outputting includes means for color-coding the defect map based on a defect severity associated with each defect.

32. The system of claim 31, wherein the means for color-coding the defect map includes means for providing a flashing colored light for any defect having a high defect severity.

33. The system of claim 32, wherein at least one review level can provide aerial images of each defect and a corresponding reference image of that defect.

34. The system of claim 20, further comprising at least one of:

means for entering a status for each defect based on a user'"'"'s review of the results of the job; and

means for providing a history of statuses for each defect based on users'"'"' reviews of the results of the job.

35. The system of claim 20, wherein the means for outputting provides a graphic user interface.

36. The system of claim 35, wherein the means for outputting interfaces with a web browser to provide the graphic user interface.

37. A computer program product comprising:

a computer usable medium having a computer readable program code embodied there for causing a computer to analyze defects of a mask used in photolithography, the computer readable program code comprising;

code that loads a mask file into a defect analysis tool;

code that specifies a job to be run using the mask file, wherein the job defines parameters used in processes performed uniformly for defects on the mask, the parameters including settings relating to the mask, an inspection system that provided information for the mask file, and a stepper that can be used in exposing the mask during photolithography;

code that manages and distributes the job to computation resources;

code that runs the job using the mask file and defined parameters on the computation resources; and

code that outputs results of the job, wherein the results include printability results for the defects on the mask.

38. The computer program product of claim 37, further including code that converts mask data into a standard mask format file (MFF).

39. The computer program product of claim 37, wherein the code that manages and distributes the job includes a job manager.

40. The computer program product of claim 39, wherein the job manager allows multiple jobs to be run in parallel.

41. The computer program product of claim 37, wherein the code that outputs results includes code for providing multiple review levels for a user.

42. The computer program product of claim 37, further comprising at least one of:

code that enters a status for each defect based on a user'"'"'s review of the results of the job; and

code that provides a history of statuses for each defect based on users'"'"' reviews of the results of the job.