Automated metrology recipe generation

• US 7,631,286 B2
• Filed: 12/30/2005
• Issued: 12/08/2009
• Est. Priority Date: 12/30/2005
• Status: Active Grant

• Current Assignee: Wafertech LLC (Taiwan Semiconductor Manufacturing Company Limited)
• Original Assignee: Wafertech LLC (Taiwan Semiconductor Manufacturing Company Limited)
• Inventors: Westfall, Scott, Piper, Daniel
• Primary Examiner(s): Rossoshek; Helen
• Application Number:
  US11/323,255
• Publication Number:
  US 20070156275A1
• Time in Patent Office: 1,439 Days
• Field of Search: 716/4, 716/10, 716/19, 716/21, 703/1, 703/14
• US Class Current: 716/52
• CPC Class Codes: G03F 7/70508 Data handling in all parts of the microlithographic apparatus, e.g. handling pattern data for addressable masks or data transfer to or from different components within the exposure apparatus
• CPC Class Codes: G03F 7/70525 Controlling normal operating mode, e.g. matching different apparatus, remote control or prediction of failure
• CPC Class Codes: G03F 7/70625 Dimensions, e.g. line width, critical dimension [CD], profile, sidewall angle or edge roughness
• CPC Class Codes: H01L 21/67253 Process monitoring, e.g. flow or thickness monitoring

Abstract

A method, system and encoded computer instructions provide for automatic generation of a metrology recipe without referencing a wafer. The highly accurate metrology recipe provides for locating measurement locations corresponding to test features on the wafer and directing the metrology tool to the locations, by calculating coordinates for the measurement locations based on mask data, lithography tool data, CAD data and process data. The metrology recipe directs the metrology tool to within 10 microns of test features formed on the wafer. Criteria may be input to a data base to identify multiple existing recipes and the automatically generated recipe may be generated to replace each identified recipe.

Claims

1. A method of directing a metrology tool to a measurement location of a test feature formed on a wafer in a pattern transferred from a mask onto said wafer, said method comprising:

determining coordinates of at least one measurement location of said test feature on said wafer by manipulating mask data, CAD data, and lithography tool data,

the mask data including field size of a mask image, width of a scribe line peripherally surrounding said mask image, center shift of said mask image relative to a mask origin, and test structure coordinates indicative of a test structure origin relative to said mask origin,

the CAD data including test feature coordinate data indicative of a position of said test feature relative to said test structure origin, and

the lithography tool data including a mask magnification factor; and

automatically creating a metrology recipe including instructions that, by themselves, to direct said metrology tool to at least one said measurement location without said metrology tool optically referencing said test feature formed on said wafer;

providing said metrology recipe to said metrology tool;

said metrology recipe directing said metrology tool to said measurement location based only on said instructions; and

said metrology tool automatically measuring said test feature at said measurement location.

2. The method as in claim 1, wherein said measurement location is within 10 microns of said test feature as formed on said wafer.

3. The method as in claim 1, further comprising performing CAD mapping to obtain said test feature coordinate data.

4. The method as in claim 1, wherein

the mask comprises a reticle having a reticle pattern,

the pattern comprises a plurality of said reticle patterns formed on said wafer,

the lithography tool data further includes x, y grid data indicative of locations of said reticle patterns on said wafer,

the determining comprises determining coordinates of a plurality of said measurement locations, each defined relative to a corresponding one of said mask origins, and

the metrology tool automatically measuring said test feature comprises measuring a plurality of said test features, each starting at a corresponding one of said measurement locations, and includes said metrology tool locating a plurality of origin locations on said wafer, each corresponding to one of said mask origins, based on said x, y grid data.

5. The method as in claim 4, wherein the automatically measuring further comprises said metrology tool automatically globally aligning to locate each of said origin locations.

6. The method as in claim 1, wherein said measurement location is within 10 microns of said test feature when said wafer is automatically loaded onto said metrology tool.

7. The method as in claim 1, wherein said mask comprises a reticle, said pattern comprises a plurality of reticle patterns formed on said wafer, said determining coordinates comprises determining a plurality of said measurement locations, wherein said lithography tool data further includes x, y grid data indicative of locations of said reticle patterns on said wafer, said automatically creating includes defining each of said coordinates relative to a corresponding said mask origin, and wherein said metrology recipe directing said metrology tool further comprises causing said metrology tool to locate each of said plurality of measurement locations by first locating a corresponding one of said mask origins using global alignment techniques.

8. The method as in claim 1, further comprising providing instructions to said metrology tool indicative of a type of measurement to be performed.

9. The method as in claim 8, wherein said type of measurement comprises critical dimension (CD) measurement.

10. The method as in claim 1, further comprising querying a process flow data base to determine a mask level and wherein at least said mask data and said CAD data are based on said mask level.

11. The method as in claim 1, wherein said determining includes a recipe generator apparatus querying a mask server to obtain said mask data, querying a CAD data base to obtain said CAD data and querying a lithography tool server to obtain said lithography tool data.

12. The method as in claim 1, further comprising, prior to said determining:

providing a database containing a plurality of existing first recipes for metrology measurement;

inputting at least one criterion to a system that accesses said database;

a computer product querying said database and identifying at least one identified recipe of said plurality of existing first recipes that satisfies said criteria; and

wherein said metrology recipe is one said at least one identified recipe.

13. A method of directing a metrology tool to a measurement location of a test feature formed on a wafer in a pattern transferred from a mask onto said wafer, said method comprising:

querying a process data base to identify a mask level;

querying a mask server to obtain mask data, querying a user defined data base to obtain CAD data, querying a lithography data base to obtain lithography tool data and manipulating said mask data, CAD data, and lithography tool data, said CAD data and said mask data dependant or said mask level;

determining at least one measurement location on said wafer, each said measurement location having coordinates determined by said mask data, said CAD data, and said lithography tool data and representing a location of said test feature on said wafer; and

automatically creating said a metrology recipe including instructions that, by themselves, direct said metrology tool to locate the at least one measurement location without said metrology tool optically referencing the test feature formed on the wafer and to perform a measurement at the measurement location;

providing said metrology recipe to said metrology tool;

said metrology recipe directing said metrology tool to said measurement location based only on said instructions; and

said metrology tool automatically measuring said test feature at said measurement location.

14. The method as in claim 13, wherein

the mask data includes field size of a mask image, width of a scribe line peripherally surrounding the mask image, center shift of the mask image relative to a mask origin, and coordinates indicative of a test structure origin relative to the mask origin,

the CAD data includes test feature coordinate data indicative of a position of the test feature relative to the test structure origin,

the lithography tool data includes a mask magnification factor, and

the measurement location is within 10 microns of the test feature as formed on the wafer.

15. The method as in claim 13, wherein the pattern comprises a plurality of mask patterns formed from the mask, the lithography tool data includes x, y grid data indicative of locations of the mask origin formed on the wafer, and the automatically creating further includes further instructions directing the metrology tool to perform a measurement at a plurality of the measurement locations, each defined relative to the mask origin and a corresponding one of the locations.

16. A computer readable storage medium encoded with computer program code, wherein when the computer program code is executed a processor, the processor performs a method for directing a metrology tool to a measurement location of a test feature formed on a wafer in a pattern transferred from a mask onto said wafer, said method comprising:

determining coordinates of at least one measurement location of the test feature on the wafer by manipulating mask data, CAD data, and lithography tool data,

the mask data including field size of a mask image, width of a scribe line peripherally surrounding the mask image, center shift of the mask image relative to a mask origin, and test structure coordinates indicative of a test structure origin relative to the mask origin,

the CAD data including test feature coordinate data indicative of a position of the test structure relative to the test structure origin, and

the lithography tool data including a mask magnification factor; and

automatically creating the metrology recipe that includes instructions that, by themselves, direct the metrology tool to at least one said measurement location without said metrology tool optically referencing the test feature on the wafer;

delivering said metrology recipe to said metrology tool;

said metrology recipe directing said metrology tool to said measurement location based only on said instructions; and

said metrology tool automatically measuring said test feature at said measurement location.

17. The computer readable storage medium as in claim 16, the computer readable storage medium further comprising further instructions for performing CAD mapping to obtain the test feature coordinate data.

18. The computer readable storage medium as in claim 16, wherein the measurement location is within 10 microns of the test feature on the wafer when the wafer is automatically loaded onto the metrology tool.

19. The computer readable storage medium as in claim 16, the computer readable storage medium further comprising further instructions that identify a type of metrology measurement to be carried out.

20. The computer readable storage medium as in claim 19, wherein the mask comprises a reticle, the pattern comprises a plurality of reticle patterns formed on the wafer, the lithography tool data further includes x, y grid data indicative of locations of the reticle patterns on the wafer, the determining comprises further instructions for determining coordinates of a plurality of the measurement locations, each defined relative to a corresponding, one of the mask origins, and wherein the instructions that, by themselves, direct the metrology tool to perform a type of metrology measurement comprise instructions for measuring a plurality of the test features and includes the metrology tool locating a plurality of origin locations on the wafer, each corresponding to one of the mask origins, based on the x, y grid data.

21. The computer readable storage medium as in claim 20, wherein the metrology recipe further directs the metrology tool to automatically globally align to each of the origin locations and to perform a measurement at each the measurement location.

22. The computer readable storage medium as in claim 20, wherein said method further comprises:

accessing a database containing a plurality of existing first recipes for metrology measurement;

querying said database and identifying at least one identified recipe of said plurality of existing first recipes that satisfies at least one criteria input to said database; and

wherein said metrology recipe is one said at feast one identified recipe.

23. The computer readable storage medium as in claim 22, wherein said criteria comprises at least one of technology type, mask level, and device type.

24. The computer readable storage medium as in claim 16, wherein the method further comprises querying a process flow data to determine mask level, wherein at least the mask data and the CAD data depend upon the mask level.

25. The computer readable storage medium as in claim 16, wherein the method further comprises:

a recipe generator apparatus querying a mask server to obtain the mask data, querying a user defined data base to obtain the CAD data and querying a lithography tool server to obtain the lithography tool data.

26. A computer readable storage medium encoded with computer code, wherein when the computer program code is executed by a processor, the processor performs a method for directing for a metrology tool to at feast one measurement location of a test feature formed on a wafer in a pattern transferred from a mask onto said wafer, the method comprising:

querying a process data base to identify a mask level;

querying a mask server to obtain mask data, querying a user defined data base to obtain CAD data, querying a lithography tool data base to obtain lithography tool data and manipulating the mask data, CAD data, and lithography tool data, the CAD data and the mask data dependant on the mask level;

determining at least one measurement location on the wafer, the measurement location having coordinates determined by manipulating the mask data, the CAD data, and the lithography tool data and representing a location of the test feature on the wafer; and

automatically creating a metrology recipe for that, by itself, directs the metrology tool to the at least one measurement location and to perform a measurement at the measurement location without the metrology tool optically referencing the test feature formed on the wafer;

delivering said metrology recipe to said metrology tool;

said metrology recipe directing said metrology tool to the measurement location based only on said metrology recipe; and

said metrology tool automatically measuring said at least one feature at the at least one measurement location.

27. The computer readable storage medium as in claim 26, wherein

the mask data includes field size of a mask image, width of a scribe line peripherally surrounding the mask image, center shift of the mask image relative to a mask origin, and coordinates indicative of a test structure origin relative to the mask origin,

the CAD data includes test feature coordinate data indicative of a position of the test feature relative to the test structure origin,

the lithography tool data includes a mask magnification factor, and

the measurement location is within 10 microns of the test feature formed on the wafer.

29. The metrology recipe creation system as in claim 26, the metrology tool including means for locating a plurality of mask origins formed on the wafer and wherein the means for automatically creating the metrology recipe includes the metrology recipe identifying a plurality of measurement locations based on the plurality of mask origins.

28. A metrology recipe creation system for automatic generation of a metrology recipe that directs a metrology tool to locate and measure a test feature formed on a wafer in a pattern transferred from a mask onto said wafer, the system comprising:

a metrology tool;

means for determining coordinates of at least one measurement location of the test feature on the wafer by manipulating mask data, CAD data, and lithography tool data,

the mask data including field size of a mask image, width of a scribe line peripherally surrounding the mask image, center shift of the mask image relative to a mask origin, and test structure coordinates indicative of a test structure origin relative to the mask origin,

the CAD data including test feature coordinate data indicative of a position of the test feature relative to the test structure origin, and

the lithography tool data including a mask magnification factor; and

means for automatically creating the metrology recipe that, by itself, directs the metrology tool to locate and measure the test feature formed; and

means for delivering said metrology recipe to said metrology tool and causing said metrology tool to locate the test feature based only on said metrology recipe; and

means for causing said metrology tool to automatically measure said test feature at the measurement location.

30. The metrology recipe creation system as in claim 28, further comprising means for querying the mask data, the CAD data and the lithography tool data.

31. The metrology recipe creation system as in claim 28, further comprising:

a database containing a plurality of existing first recipes for metrology measurement;

a first system that accesses said database;

means for inputting at least one criteria to said first system; and

a computer readable storage medium encoded with computer code, wherein when the computer program code is executed by a processor, the processor performs a method for querying said database and identifying at least one identified recipe of said plurality of existing first recipes that satisfies said at least one criteria, and

wherein said metrology recipe is one of said at least one identified recipe.

32. The metrology recipe creation system as in claim 28, wherein said criteria comprises at least one of technology type, mask level, and device type.