Identifying defects

• US 8,571,299 B2
• Filed: 08/30/2010
• Issued: 10/29/2013
• Est. Priority Date: 08/30/2010
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Fayaz, Mohammed F., Lee, Julie L., Pastel, Leah M., Kassab, Maroun
• Primary Examiner(s): MARIAM, DANIEL G
• Application Number:
  US12/871,039
• Publication Number:
  US 20120050728A1
• Time in Patent Office: 1,156 Days
• Field of Search: 382141-149, 382/218, 382/209, 382/216, 382/254, 382/293, 382/296, 348/92
• US Class Current: 382/145
• CPC Class Codes: G01N 2021/8864 Mapping zones of defects
• CPC Class Codes: G01N 21/95607 using a comparative method
• CPC Class Codes: H01L 22/12 for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions electrical measurement of diffusions H01L22/14
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

Identifying systematic defects in wafer processing including performing defect inspection of a plurality of wafers, identifying defects in each of the plurality of wafers as not being associated with a trivial and/or known root cause, determining a physical location on each wafer where each of the defects occurs and correlating the physical locations where each of the defects occurs with cell instances defined for those physical locations.

Claims

1. A method for identifying systematic defects in wafer processing, comprising:

performing defect inspection of a plurality of wafers;

identifying defects in each of the plurality of wafers as not being associated with a trivial and/or known root cause;

determining a physical location on each wafer where each of the defects occurs; and

correlating the physical locations where each of the defects occurs with each one of different cell instances of a same cell respectively defined for those physical locations, the different cell instances having multiple rotational orientations in a hierarchical layout,

the correlating comprising;

normalizing the respective rotational orientations of the different cell instances into a single rotational orientation relative to layout geometry; and

defect mapping to the different cell instances based on the single rotational orientation relative to the layout geometry,

wherein the method is performed using a computer or a processor.

2. The method according to claim 1, wherein the performing of defect inspection comprises wafer based defect inspection.

3. The method according to claim 2, further comprising discarding the defects associated with trivial and/or known root causes.

4. The method according to claim 1, wherein the identifying of defects as not being associated with a trivial and/or known root cause comprises determining that the defects occur at a statistically significant rate.

5. The method according to claim 1, wherein the identifying of defects as not being associated with a trivial and/or known root cause comprises determining that the defects are clustered.

6. The method according to claim 1, wherein the identifying of defects as not being associated with a trivial and/or known root cause comprises determining a cause of the defects.

7. The method according to claim 1, wherein the determining of the physical locations comprises defect mapping.

8. The method according to claim 1, wherein the defect mapping is based on secondary design considerations.

9. The method according to claim 8, wherein the secondary considerations comprise power, timing, logic organization, test and test coverage, diagnostic, robustness, pattern density, proximity to a change in pattern density, and sensitive layout structures.

10. The method according to claim 1, wherein the cell instances are derived from a hierarchical layout of multiple designs of each of the plurality of wafers.

11. The method according to claim 1, wherein the cell instances comprise pseudo-cell instances derived from a hierarchical layout of each of the plurality of wafers.

12. The method according to claim 11, wherein pseudo cells comprise similar cell layouts, cells that define a specific back end of line (BEOL) layout, cells that have similar image processing results and cells that are identified by pattern recognition.

13. A non-transitory computer readable medium on which executable instructions are stored, which, when executed, cause a processing unit of a computing device to perform the method according to claim 1.

14. A method for identifying systematic defects in wafer processing, comprising:

inputting defect data for a plurality of wafers into a processing unit of a computing device having a non-transitory computer readable medium on which executable instructions are stored, which, when executed, cause the processing unit to;

analyze wafer level defect data to identify defects with trivial and/or known root causes,

ascertain defect coordinates,

translate defects coordinates to reticle and design coordinate spaces, and

extract placement information for each one of different cell instances of a same cell of each reticle and design coordinate space, the different cell instances having multiple rotational orientations;

normalize the respective rotational orientations of the different cell instances into a single rotational orientation; and

defect map the defects to the different cell instances of the reticle and design coordinate spaces based on the single rotational orientation.

15. The method according to claim 14, wherein the executable instructions, when executed, further cause the processing unit to compare the wafer level defect data against design rule checking results.

16. The method according to claim 14, wherein the executable instructions, when executed, further cause the processing unit to:

identify clusters of defects within each cell of each design based on correlation between the defect coordinates and the design coordinates, and

extract defect information associated with the wafer level defect data clustered within each cell of each design.

17. A method for identifying systematic defects in wafer processing comprising wafer based defect analysis, wafer-to-reticle defect stacking, reticle-to-design defect mapping and design-to-cells defect mapping,

the design-to-cells defect mapping comprising:

normalizing into a single rotational orientation respective rotational orientations of different cell instances of a same cell where occurrences of defects not associated with trivial and/or known root causes are located; and

defect mapping the defects to the different cell instances based on the single rotational orientation,

wherein the method is performed using a computer or a processor.

18. A system to identify systematic defects in wafer processing, comprising:

a wafer inspection apparatus to inspect a plurality of wafers for defects and to generate defect data in accordance with results of the inspection;

a networking unit coupled to the wafer inspection apparatus; and

a computing device, coupled to the networking unit, to receive the defect data generated by the wafer inspection apparatus by way of the networking unit, the computing device including a processing unit and a non-transitory computer readable medium on which executable instructions are stored, which, when executed, cause the processing unit to identify defects in each of the plurality of wafers as not being associated with trivial and/or known root causes, to determine a physical location on each wafer where each of the defects occurs and to correlate the physical locations where each of the defects occurs with each one of different cell instances of a same cell respectively defined for those physical locations, the different cell instances having multiple rotational orientations, the correlation being executed by;

a normalization of the respective rotational orientations of the different cell instances into a single rotational orientation; and

a defect mapping to the different cell instances based on the single rotational orientation.