Determining and analyzing integrated circuit yield and quality

• US 7,512,508 B2
• Filed: 09/06/2005
• Issued: 03/31/2009
• Est. Priority Date: 09/06/2004
• Status: Active Grant

• Current Assignee: Siemens Industry Software Limited (Siemens AG)
• Original Assignee: Mentor Graphics Corporation (Siemens AG)
• Inventors: Chen, Gang, Sharma, Manish, Rajski, Janusz, Keim, Martin, Tang, Huaxing, Tamarapalli, Nagesh
• Primary Examiner(s): Wachsman; Hal D
• Application Number:
  US11/221,395
• Publication Number:
  US 20060066339A1
• Time in Patent Office: 1,302 Days
• Field of Search: 702/118, 702/81, 702/84, 702/181
• US Class Current: 702/118
• CPC Class Codes: G01R 31/01 Subjecting similar articles in turn to test, e.g. "go/no-go" tests in mass production; Testing objects at points as they pass through a testing station testing of cables continuously passing the testing apparatus G01R31/59; testing dielectric strength or breakdown voltage G01R31/12
• CPC Class Codes: G01R 31/2846 using hard- or software simulation or using knowledge-based systems, e.g. expert systems, artificial intelligence or interactive algorithms
• CPC Class Codes: G01R 31/2853 Electrical testing of internal connections or -isolation, e.g. latch-up or chip-to-lead connections G01R31/31717 takes precedence; test of chip-to-PCB or lead-to-PCB connections G01R31/66
• CPC Class Codes: G01R 31/2894 Aspects of quality control [QC] G01R31/31718 takes precedence; program control for QC G05B19/41875
• CPC Class Codes: G01R 31/31704 Design for test; Design verification concerning scan tests G01R31/318583; computer-aided design G06F30/00
• CPC Class Codes: G01R 31/31835 Analysis of test coverage or failure detectability
• CPC Class Codes: G06F 11/2273 Test methods

Abstract

Methods, apparatus, and systems for computing and analyzing integrated circuit yield and quality are disclosed herein. For example, in one exemplary method disclosed herein information is received from processing test responses of integrated circuits designed for functional use in electronic devices. In this embodiment, the information is indicative of integrated circuit failures observed during testing of the integrated circuits and of possible yield limiting factors causing the integrated circuit failures. Probabilities that one or more of the possible yield limiting factors in the integrated circuits actually caused the integrated circuit failures are determined by statistically analyzing the received information. The probabilities that one or more possible yield limiting factors actually caused the integrated circuit failures are reported. Tangible computer-readable media comprising computer-executable instructions for causing a computer to perform any of the described methods are also disclosed.

Claims

1. A computer-implemented method for analyzing integrated circuit yield, comprising:

receiving information from processing test responses of integrated circuits designed for functional use in electronic devices, the information being indicative of integrated circuit failures observed during testing of the integrated circuits;

determining a list of suspect yield limiting factors for each failing integrated circuit from the received information, the list of suspect yield limiting factors for a respective failing integrated circuit comprising yield limiting factors that potentially caused the respective failing integrated circuit to fail;

determining probabilities that one or more of the suspect yield limiting factors in the integrated circuits actually caused the integrated circuit failures, the act of determining the probabilities comprising statistically analyzing the lists of suspect yield limiting factors determined for each failing integrated circuit; and

reporting the probabilities that one or more suspect yield limiting factors actually caused the integrated circuit failures.

2. The computer-implemented method of claim 1, further comprising determining an estimate of the yield of the integrated circuits based at least in part on the determined probabilities.

3. The computer-implemented method of claim 1, wherein the integrated circuits comprise a first set of integrated circuits, the method further comprising determining an estimate of the yield of a second set of integrated circuits based at least in part on the determined probabilities.

4. The computer-implemented method of claim 1, further comprising determining an estimate of the escape rate of a respective suspect yield limiting factor or of the integrated circuits based at least in part on the determined probabilities.

5. The computer-implemented method of claim 1, wherein the integrated circuits comprise a first set of integrated circuits, the method further comprising determining an estimate of the escape rate of a suspect yield limiting factor of a second set of integrated circuits or of the second set of integrated circuits based at least in part on the determined probabilities.

6. The computer-implemented method of claim 1 performed repetitively over time, the method further comprising determining production trends based on changes in the determined probabilities observed over time.

7. The computer-implemented method of claim 1, further comprising adjusting one or more design manufacturing rules based at least in part on the reported probabilities.

8. The computer-implemented method of claim 1, further comprising adjusting one or more defect extraction rules used to identify potential defects in a design of the integrated circuits based at least in part on the reported probabilities.

9. The computer-implemented method of claim 1, further comprising providing recommended modifications for one or more features in the integrated circuits based at least in part on the reported probabilities.

10. The computer-implemented method of claim 9, further comprising producing one or more integrated circuits having the modified one or more features.

11. The computer-implemented method of claim 1, wherein the act of reporting comprises generating a graphical representation of the probabilities.

12. The computer-implemented method of claim 11, wherein the graphical representation comprises a pareto chart.

13. The computer-implemented method of claim 1, wherein the list of suspect yield limiting factors is determined using one or more of:

(a) at least one compressed fault dictionary;

or (b) incremental diagnosis of the received information.

14. The computer-implemented method of claim 1, wherein the act of determining probabilities comprises:

estimating a probability that a respective suspect yield limiting factor caused an associated respective integrated circuit failure, and

iteratively solving a system of equations relating the estimated probability to an actual probability that the respective suspect yield limiting factor caused the associated failure.

15. The computer-implemented method of claim 1, wherein the suspect yield limiting factors comprise at least one of:

(a) nets in an integrated circuit layout, (b) features in the integrated circuit layout, or (c) design manufacturing rules associated with the manufacture of the integrated circuit.

16. The computer-implemented method of claim 1, wherein the act of determining the probabilities further comprises identifying nets that fail at a substantially higher rate than other nets.

17. The computer-implemented method of claim 1, wherein the determining the list of suspect yield limiting factors includes identifying potential defects in the integrated circuits using a fault dictionary in which one or more potential defects are identified by applying a bit mask.

18. The computer-implemented method of claim 1, wherein the act of determining the list of suspect yield limiting factors comprising ranking the suspect yield limiting factors for each failing integrated circuit.

19. A computer-implemented method for analyzing integrated circuit yield, comprising:

receiving information from processing test responses of integrated circuits designed for functional use in electronic devices, the information being indicative of integrated circuit failures observed during testing of the integrated circuits and of possible yield limiting factors causing the integrated circuit failures;

determining probabilities that one or more of the possible yield limiting factors in the integrated circuits actually caused the integrated circuit failures, the act of determining the probabilities comprising statistically analyzing the received information; and

reporting the probabilities that one or more possible yield limiting factors actually caused the integrated circuit failures,

wherein the integrated circuits are designed in accordance with one or more design manufacturing rules, the method further comprising estimating a yield sensitivity curve based at least in part on the determined probabilities for at least one of the design manufacturing rules.

20. The computer-implemented method of claim 19, wherein the information received comprises one or more of the following:

(a) diagnosis results obtained from diagnosing the integrated circuit failures;

(b) one or more lists of yield limiting factors;

or (c) information about detection of the yield limiting factors during the testing.

21. A computer-implemented method for analyzing integrated circuit yield, comprising:

receiving information from processing test responses of integrated circuits designed for functional use in electronic devices, the information being indicative of integrated circuit failures observed during testing of the integrated circuits and of possible yield limiting factors causing the integrated circuit failures;

determining probabilities that one or more of the possible yield limiting factors in the integrated circuits actually caused the integrated circuit failures, the act of determining the probabilities comprising statistically analyzing the received information; and

reporting the probabilities that one or more possible yield limiting factors actually caused the integrated circuit failures,

wherein the integrated circuits tested have a common design, and wherein the act of determining probabilities comprises partitioning the design of the integrated circuits into multiple design blocks, each design block comprising a subset of the possible yield limiting factors.

22. The computer-implemented method of claim 21, wherein the partitioning comprises:

simulating faults associated with nets in the design of the integrated circuits;

identifying at least a first group of observation points that capture errors from a first set of nets and a second group of observation points that capture errors from a second set of nets; and

including the first set of nets in a first design block and the second set of nets in a second design block.

23. The computer-implemented method of claim 21, wherein the act of determining probabilities further comprises:

constructing probability models relating design block fail probabilities to fail probabilities of yield limiting factors contained in respective design blocks;

comparing the design block fail probabilities to the received information; and

computing estimated fail probabilities of yield limiting factors using regression techniques.

24. The computer-implemented method of claim 21, wherein the information received comprises one or more of the following:

(a) diagnosis results from diagnosing the integrated circuit failures;

(b) one or more lists of the possible yield limiting factors;

or (c) information about detection of the possible yield limiting factors during the testing.

25. The computer-implemented method of claim 21, further comprising determining an estimate of the yield of the integrated circuits based at least in part on the determined probabilities.

26. The computer-implemented method of claim 21, wherein the integrated circuits comprise a first set of integrated circuits, the method further comprising determining an estimate of the yield of a second set of integrated circuits based at least in part on the determined probabilities.

27. The computer-implemented method of claim 21, further comprising determining an estimate of the escape rate of a respective possible yield limiting factor or of the integrated circuits based at least in part on the determined probabilities.

28. The computer-implemented method of claim 21, wherein the integrated circuits comprise a first set of integrated circuits, the method further comprising determining an estimate of the escape rate of a possible yield limiting factor of a second set of integrated circuits or of the second set of integrated circuits based at least in part on the determined probabilities.

29. The computer-implemented method of claim 21, wherein the integrated circuits are designed in accordance with one or more design manufacturing rules, the method further comprising estimating a yield sensitivity curve for at least one of the design manufacturing rules based at least in part on the determined probabilities.

30. The computer-implemented method of claim 21 performed repetitively over time, the method further comprising determining production trends based on changes in the determined probabilities observed over time.

31. The computer-implemented method of claim 21, further comprising performing one or more of the following based at least in part on the reported probabilities:

(a) adjusting one or more design manufacturing rules;

(b) adjusting one or more defect extraction rules;

or (c) providing recommended modifications for one or more features in the integrated circuits.

32. The computer-implemented method of claim 31, wherein one or more features in the integrated circuits are modified based at least in part on the reported probabilities, the method further comprising producing one or more integrated circuits having the modified one or more features.

33. The computer-implemented method of claim 21, wherein the act of reporting comprises generating a graphical representation of the probabilities.

34. The computer-implemented method of claim 21, wherein the partitioning comprises:

simulating faults associated with nets in the design of the integrated circuits;

identifying at least a first group of observation points that capture errors from a first set of nets and a second group of observation points that capture errors from a second set of nets; and

including the first set of nets in a first design block and the second set of nets in a second design block.

35. The computer-implemented method of claim 21, wherein the act of determining probabilities further comprises:

constructing probability models relating design block fail probabilities to fail probabilities of possible yield limiting factors contained in respective design blocks;

comparing the design block fail probabilities to the received information; and

computing estimated fail probabilities of the possible yield limiting factors using regression techniques.

36. The computer-implemented method of claim 21, wherein the possible yield limiting factors comprise potential defects and wherein the information received is further indicative of one or more of the following properties associated with a respective potential defect:

a defect identifier that distinguishes the respective potential defect from other potential defects;

a derived rule identifier that identifies the defect extraction rule used to extract the respective potential defect;

a design manufacturing rule identifier that identifies the manufacturing rule that the defect extraction rules was based on;

one or more physical properties of the respective potential defect;

a physical location of the respective potential defect in the physical layout of the integrated circuit design; and

a ranking of the respective potential defect relative to other potential defects in the same class of potential defects.

37. The computer-implemented method of claim 21, wherein the received information comprises a list of suspect features.

38. A computer-implemented method for analyzing integrated circuit yield, comprising:

receiving information from processing test responses of integrated circuits designed for functional use in electronic devices, the information being indicative of integrated circuit failures observed during testing of the integrated circuits and of possible yield limiting factors causing the integrated circuit failures;

determining probabilities that one or more of the possible yield limiting factors in the integrated circuits actually caused the integrated circuit failures, the act of determining the probabilities comprising statistically analyzing the received information; and

reporting the probabilities that one or more possible yield limiting factors actually caused the integrated circuit failures,

wherein the act of determining the probabilities further comprises identifying nets that fail at a substantially higher rate than other nets and determining whether the nets that fail at a substantially higher rate than other nets occur repetitively at or near a same die location of multiple wafers containing multiples instances of dies that each contain an instance of the tested integrated circuit.

39. The computer-implemented method of claim 38, wherein the act of determining whether the nets that fail at a substantially higher rate than other nets occur repetitively at or near a same die location comprises generating a wafer defect map.

40. The computer-implemented method of claim 38, wherein the possible yield limiting factors are potential defects that may have caused the integrated circuit failures and that were extracted and targeted using extraction rules derived from design manufacturing rules, and wherein the method further comprises:

analyzing the information to determine one or more failure rates associated with one or more of the potential defects; and

reporting the determined failure rates.

41. The computer-implemented method of claim 40, wherein the information received comprises one or more of the following:

(a) diagnosis results obtained from diagnosing the circuit failures;

(b) one or more lists of the potential defects;

or (c) information about detection of the potential defects during the testing.

42. The computer-implemented method of claim 40, further comprising determining an estimate of the yield of the integrated circuits based at least in part on the determined failure rates.

43. The computer-implemented method of claim 40, wherein the integrated circuits comprise a first set of integrated circuits, the method further comprising determining an estimate of the yield of a second set of integrated circuits based at least in part on the determined failure rates.

44. The computer-implemented method of claim 40, further comprising determining an estimate of the escape rate of a respective potential defect or of the integrated circuits based at least in part on the determined failure rates.

45. The computer-implemented method of claim 40, wherein the integrated circuits comprise a first set of integrated circuits, the method further comprising determining an estimate of the escape rate of a potential defect of a second set of integrated circuits or of the second set of integrated circuits based at least in part on the determined failure rates.

46. The computer-implemented method of claim 40, further comprising estimating a yield sensitivity curve for at least one of the design manufacturing rules based at least in part on the determined failure rates.

47. The computer-implemented method of claim 38 performed repetitively over time, the method further comprising determining production trends based on changes in the determined probabilities observed over time.

48. The computer-implemented method of claim 38 further comprising performing one or more of the following based at least in part on the reported probabilities:

(a) adjusting one or more design manufacturing rules;

(b) adjusting one or more defect extraction rules;

or (c) providing recommended modifications for one or more features in the integrated circuits.

49. The computer-implemented method of claim 48, wherein one or more features in the integrated circuits are modified based at least in part on the reported probabilities, the method further comprising producing one or more integrated circuits having the modified one or more features.

50. The computer-implemented method of claim 38, wherein the information received comprises diagnostic results obtained through application of at least one fault dictionary.

51. The computer-implemented method of claim 50, wherein the at least one fault dictionary comprises a compressed fault dictionary that uses one or more bit masks to identify potential defects.

52. One or more tangible computer-readable media storing computer-executable instructions for causing a computer to perform a method, the method comprising:

receiving information from processing test responses of integrated circuits designed for functional use in electronic devices, the information being indicative of integrated circuit failures observed during testing of the integrated circuits;

determining a list of suspect yield limiting factors for each failing integrated circuit from the received information, the list of suspect yield limiting factors for a respective failing integrated circuit comprising yield limiting factors that potentially caused the respective failing integrated circuit to fail;

determining probabilities that one or more of the suspect yield limiting factors in the integrated circuits actually caused the integrated circuit failures, the act of determining the probabilities comprising statistically analyzing the lists of suspect yield limiting factors determined for each failing integrated circuit; and

reporting the probabilities that one or more suspect yield limiting factors actually caused the integrated circuit failures.

53. A computer comprising a computer-readable memory, the computer-readable memory storing instructions for causing the computer to perform a method, the method comprising:

receiving information from processing test responses of integrated circuits designed for functional use in electronic devices, the information being indicative of integrated circuit failures observed during testing of the integrated circuits;

determining a list of suspect yield limiting factors for each failing integrated circuit from the received information, the list of suspect yield limiting factors for a respective failing integrated circuit comprising yield limiting factors that potentially caused the respective failing integrated circuit to fail;

determining probabilities that one or more of the suspect yield limiting factors in the integrated circuits actually caused the integrated circuit failures, the act of determining the probabilities comprising statistically analyzing the lists of suspect yield limiting factors determined for each failing integrated circuit; and

reporting the probabilities that one or more suspect yield limiting factors actually caused the integrated circuit failures.

54. One or more tangible computer-readable media comprising computer-executable instructions for causing a computer to perform a method, the method comprising:

receiving information from processing test responses of integrated circuits designed for functional use in electronic devices, the information being indicative of integrated circuit failures observed during testing of the integrated circuits and of possible yield limiting factors causing the integrated circuit failures;

determining probabilities that one or more of the possible yield limiting factors in the integrated circuits actually caused the integrated circuit failures, the act of determining the probabilities comprising statistically analyzing the received information; and

reporting the probabilities that one or more possible yield limiting factors actually caused the integrated circuit failures,

wherein the integrated circuits tested have a common design, and wherein the act of determining probabilities comprises partitioning the design of the integrated circuits into multiple design blocks, each design block comprising a subset of the possible yield limiting factors.

55. A computer comprising a computer-readable memory, the computer-readable memory storing instructions for causing the computer to perform a method, the method comprising:

receiving information from processing test responses of integrated circuits designed for functional use in electronic devices, the information being indicative of integrated circuit failures observed during testing of the integrated circuits and of possible yield limiting factors causing the integrated circuit failures;

determining probabilities that one or more of the possible yield limiting factors in the integrated circuits actually caused the integrated circuit failures, the act of determining the probabilities comprising statistically analyzing the received information; and

reporting the probabilities that one or more possible yield limiting factors actually caused the integrated circuit failures,

wherein the integrated circuits tested have a common design, and wherein the act of determining probabilities comprises partitioning the design of the integrated circuits into multiple design blocks, each design block comprising a subset of the possible yield limiting factors.

56. One or more tangible computer-readable media comprising computer-executable instructions for causing a computer to perform a method, the method comprising:

receiving information from processing test responses of integrated circuits designed for functional use in electronic devices, the information being indicative of integrated circuit failures observed during testing of the integrated circuits and of possible yield limiting factors causing the integrated circuit failures;

determining probabilities that one or more of the possible yield limiting factors in the integrated circuits actually caused the integrated circuit failures, the act of determining the probabilities comprising statistically analyzing the received information; and

reporting the probabilities that one or more possible yield limiting factors actually caused the integrated circuit failures,

wherein the act of determining the probabilities further comprises identifying nets that fail at a substantially higher rate than other nets and determining whether the nets that fail at a substantially higher rate than other nets occur repetitively at or near a same die location of multiple wafers containing multiples instances of dies that each contain an instance of the tested integrated circuit.

57. A computer comprising a computer-readable memory, the computer-readable memory storing instructions for causing the computer to perform a method, the method comprising:

receiving information from processing test responses of integrated circuits designed for functional use in electronic devices, the information being indicative of integrated circuit failures observed during testing of the integrated circuits and of possible yield limiting factors causing the integrated circuit failures;

determining probabilities that one or more of the possible yield limiting factors in the integrated circuits actually caused the integrated circuit failures, the act of determining the probabilities comprising statistically analyzing the received information; and

reporting the probabilities that one or more possible yield limiting factors actually caused the integrated circuit failures,

wherein the act of determining the probabilities further comprises identifying nets that fail at a substantially higher rate than other nets and determining whether the nets that fail at a substantially higher rate than other nets occur repetitively at or near a same die location of multiple wafers containing multiples instances of dies that each contain an instance of the tested integrated circuit.