Hybrid inspectors

• US 9,916,965 B2
• Filed: 12/29/2016
• Issued: 03/13/2018
• Est. Priority Date: 12/31/2015
• Status: Active Grant

• Current Assignee: KLA-Tencor Corporation
• Original Assignee: KLA-Tencor Corporation
• Inventors: Bhaskar, Kris, Chen, Grace Hsiu-Ling, Wells, Keith, McMillan, Wayne, Zhang, Jing, Young, Scott, Duffy, Brian
• Primary Examiner(s): Geisel, Kara E
• Assistant Examiner(s): SMITH, MAURICE C
• Application Number:
  US15/394,792
• Publication Number:
  US 20170194126A1
• Time in Patent Office: 439 Days
• CPC Class Codes: G01N 2021/8867 using sequentially two or more inspection runs, e.g. coarse and fine, or detecting then analysing
• 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 21/956 Inspecting patterns on the surface of objects contactless testing of electronic circuits G01R31/308; testing currency G07D; manufacturing processes per se of semiconductor devices implementing a measuring step H01L22/10
• CPC Class Codes: G01N 2201/12 Circuits of general importance; Signal processing
• CPC Class Codes: G01N 2223/304 electric circuits, signal processing
• CPC Class Codes: G01N 2223/401 image processing
• CPC Class Codes: G01N 2223/418 electron microscope
• CPC Class Codes: G01N 2223/6116 semiconductor wafer
• CPC Class Codes: G01N 2223/646 flaws, defects
• CPC Class Codes: G01N 23/2251 using incident electron beams, e.g. scanning electron microscopy [SEM]
• CPC Class Codes: G03F 7/7065 Defects, e.g. optical inspection of patterned layer for defects
• CPC Class Codes: G06N 3/045 Combinations of networks
• CPC Class Codes: G06N 3/047 Probabilistic or stochastic networks
• CPC Class Codes: G06N 3/08 Learning methods
• CPC Class Codes: G06T 2207/10004 Still image; Photographic image
• CPC Class Codes: G06T 2207/10061 from scanning electron microscope
• CPC Class Codes: G06T 2207/20076 Probabilistic image processing
• CPC Class Codes: G06T 2207/20081 Training; Learning
• CPC Class Codes: G06T 2207/20084 Artificial neural networks [ANN]
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/0004 : Industrial image inspection
• CPC Class Codes: H01J 2237/24475 : Scattered electron detectors
• CPC Class Codes: H01J 2237/24495 : Signal processing, e.g. mixing of two or more signals
• CPC Class Codes: H01J 2237/2817 : Pattern inspection
• CPC Class Codes: H01J 37/06 : Electron sources; Electron guns electron sources in general H01J1/02, H01J19/02; electron guns in general H01J3/02
• CPC Class Codes: H01J 37/222 : Image processing arrangements associated with the tube image data processing or generation, in general G06T
• CPC Class Codes: H01J 37/226 : Optical arrangements for illuminating the object; optical arrangements for collecting light from the object
• CPC Class Codes: H01J 37/28 : with scanning beams H01J37/268, H01J37/292, H01J37/2955 take precedence
• CPC Class Codes: H01L 22/20 : Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps

Abstract

Hybrid inspectors are provided. One system includes computer subsystem(s) configured for receiving optical based output and electron beam based output generated for a specimen. The computer subsystem(s) include one or more virtual systems configured for performing one or more functions using at least some of the optical based output and the electron beam based output generated for the specimen. The system also includes one or more components executed by the computer subsystem(s), which include one or more models configured for performing one or more simulations for the specimen. The computer subsystem(s) are configured for detecting defects on the specimen based on at least two of the optical based output, the electron beam based output, results of the one or more functions, and results of the one or more simulations.

Claims

1. A system configured to detect defects on a specimen, comprising:

an optical based subsystem configured for generating optical based output for a specimen by directing light to and detecting light from the specimen;

an electron beam based subsystem configured for generating electron beam based output for the specimen by directing electrons to and detecting electrons from the specimen;

one or more computer subsystems configured for receiving the optical based output and the electron beam based output generated for the specimen, wherein the one or more computer subsystems comprise one or more virtual systems configured for performing one or more functions using at least some of the optical based output and the electron beam based output generated for the specimen, and wherein the one or more virtual systems are not capable of having the specimen disposed therein; and

one or more components executed by the one or more computer subsystems, wherein the one or more components comprise one or more models configured for performing one or more simulations for the specimen; and

wherein the one or more computer subsystems are further configured for detecting defects on the specimen based on at least two of the optical based output, the electron beam based output, results of the one or more functions, and results of the one or more simulations, wherein the one or more computer subsystems are further configured for performing said detecting the defects using the one or more models, and wherein the one or more models are further configured for selecting the at least two of the optical based output, the electron beam based output, the results of the one or more functions, and the results of the one or more simulations that are used for said detecting the defects.

2. The system of claim 1, wherein the one or more virtual systems are further configured for generating a reference for the specimen based on design information for the specimen, and wherein the reference is used for detecting the defects on the specimen.

3. The system of claim 1, wherein detecting the defects is further performed based on design information for the specimen in combination with the at least two of the optical based output, the electron beam based output, the results of the one or more functions, and the results of the one or more simulations.

4. The system of claim 1, wherein detecting the defects comprises comparing the optical based output to a first reference and comparing the electron beam based output to a second reference.

5. The system of claim 1, wherein the one or more virtual systems are further configured for storing all of the optical based output and the electron beam based output generated for the specimen indefinitely.

6. The system of claim 1, wherein the one or more virtual systems are further configured for generating information for the specimen without using the optical based output and the electron beam based output generated for the specimen and for storing the information generated by the one or more virtual systems in the one or more virtual systems.

7. The system of claim 1, wherein the one or more computer subsystems are further configured for receiving information for the specimen generated by another system, wherein the one or more virtual systems are further configured for storing the information, and wherein detecting the defects is further performed based on the stored information in combination with the at least two of the optical based output, the electron beam based output, the results of the one or more functions, and the results of the one or more simulations.

8. The system of claim 1, wherein the specimen comprises design for inspection structures, and wherein the one or more computer subsystems are further configured for extracting at least one of the optical based output and the electron beam based output generated for the design for inspection structures and performing one or more functions based on the extracted output.

9. The system of claim 1, wherein detecting the defects comprises volumetric inspection.

10. The system of claim 1, wherein detecting the defects comprises hyperspectral inspection.

11. The system of claim 1, wherein detecting the defects comprises multi-mode inspection.

12. The system of claim 1, wherein the one or more models are further configured for classifying the detected defects, and wherein the one or more computer subsystems are further configured for sampling the detected defects based on results of said classifying.

13. The system of claim 1, wherein the one or more components further comprise a single recipe configured for controlling at least the optical based subsystem and the electron beam based subsystem.

14. The system of claim 1, wherein the one or more computer subsystems are further configured for training the one or more models with information for defects detected in a process window qualification method.

15. The system of claim 1, wherein the one or more models comprise one or more deep learning based models.

16. The system of claim 1, wherein the one or more models comprise one or more machine learning based models.

17. The system of claim 1, wherein the one or more models comprise one or more discriminative models.

18. The system of claim 1, wherein the one or more models comprise one or more generative models.

19. The system of claim 1, wherein the one or more simulations comprise generating one or more simulated images for the specimen based on design information for the specimen, wherein the electron beam based output comprises one or more actual images of the specimen generated by the electron beam based subsystem, and wherein the one or more simulated images illustrate how the specimen appears in the one or more actual images.

20. The system of claim 1, wherein the one or more simulations comprise generating one or more simulated images for the specimen based on design information for the specimen and the optical based output, wherein the electron beam based output comprises one or more actual images of the specimen generated by the electron beam based subsystem, and wherein the one or more simulated images illustrate how the specimen appears in the one or more actual images.

21. The system of claim 1, wherein said detecting comprises determining if defects detected based on the optical based output are nuisances based on the electron beam based output.

22. The system of claim 1, wherein said generating at least one of the optical based output and the electron beam based output are performed based on information for metrology markers on the specimen, and wherein the one or more computer subsystems are further configured to generate metrology information for the specimen based on the at least one of the optical based output and the electron beam based output generated at the metrology markers.

23. The system of claim 1, wherein the optical based output is generated by the optical based subsystem with two or more different values of a parameter of the optical based subsystem.

24. The system of claim 1, wherein the electron beam based output is generated by the electron beam based subsystem with two or more different values of a parameter of the electron beam based subsystem.

25. The system of claim 1, wherein the specimen is a wafer.

26. The system of claim 1, wherein the specimen is a reticle.

27. The system of claim 1, wherein the optical based subsystem and the electron beam based subsystem are only coupled to each other via the one or more computer subsystems.

28. The system of claim 1, wherein the optical based subsystem and the electron beam based subsystem are only coupled to each other via the one or more computer subsystems and a common specimen handling subsystem.

29. A computer-implemented method for detecting defects on a specimen, comprising:

generating optical based output for a specimen by directing light to and detecting light from the specimen;

generating electron beam based output for the specimen by directing electrons to and detecting electrons from the specimen;

receiving the optical based output and the electron beam based output generated for the specimen with one or more computer systems, wherein the one or more computer systems comprise one or more virtual systems configured for performing one or more functions using at least some of the optical based output and the electron beam based output generated for the specimen, wherein the one or more virtual systems are not capable of having the specimen disposed therein, wherein one or more components are executed by the one or more computer systems, and wherein the one or more components comprise one or more models configured for performing one or more simulations for the specimen; and

detecting defects on the specimen based on at least two of the optical based output, the electron beam based output, results of the one or more functions, and results of the one or more simulations, wherein said detecting the defects is performed using the one or more models, and wherein the one or more models are further configured for selecting the at least two of the optical based output, the electron beam based output, the results of the one or more functions, and the results of the one or more simulations that are used for said detecting the defects.

30. A non-transitory computer-readable medium, storing program instructions executable on one or more computer systems for performing a computer-implemented method for detecting defects on a specimen, wherein the computer-implemented method comprises:

generating optical based output for a specimen by directing light to and detecting light from the specimen;

generating electron beam based output for the specimen by directing electrons to and detecting electrons from the specimen;

receiving the optical based output and the electron beam based output generated for the specimen with one or more computer systems, wherein the one or more computer systems comprise one or more virtual systems configured for performing one or more functions using at least some of the optical based output and the electron beam based output generated for the specimen, wherein the one or more virtual systems are not capable of having the specimen disposed therein, wherein one or more components are executed by the one or more computer systems, and wherein the one or more components comprise one or more models configured for performing one or more simulations for the specimen; and

detecting defects on the specimen based on at least two of the optical based output, the electron beam based output, results of the one or more functions, and results of the one or more simulations, wherein said detecting the defects is performed using the one or more models, and wherein the one or more models are further configured for selecting the at least two of the optical based output, the electron beam based output, the results of the one or more functions, and the results of the one or more simulations that are used for said detecting the defects.