System and method for tilt calculation based on overlay metrology measurements

Patent metadata

Field	Value
Publication number	US-11360398-B2
Application number	US-202017087417-A
Country	US
Kind code	B2
Filing date	Nov 2, 2020
Priority date	Nov 14, 2019
Publication date	Jun 14, 2022
Grant date	Jun 14, 2022

Abstract

A metrology system includes a controller communicatively coupled to one or more metrology tools. In another embodiment, the controller includes one or more processors configured to execute program instructions causing the one or more processors to receive one or more overlay metrology measurements of one or more metrology targets of the metrology sample from the one or more metrology tools; determine tilt from the one or more measurement overlay measurements; and determine one or more correctables for at least one of one or more lithography tools or the one or more metrology tools to adjust for the tilt, where the one or more correctables are configured to reduce an amount of tilt in the sample or overlay inaccuracy of the one or more overlay metrology measurements. The program instructions further cause the one or more processors to predict tilt with a simulator based on at least the determined tilt.

First claim

What is claimed:

1. A system for tilt calculation based on overlay metrology measurements, comprising:
a controller communicatively coupled to one or more metrology tools configured to hold a metrology sample, wherein the controller includes one or more processors configured to execute program instructions causing the one or more processors to:
receive one or more overlay metrology measurements of one or more metrology targets of the metrology sample from the one or more metrology tools, wherein the one or more overlay metrology measurements are taken following an after develop inspection (ADI) process;
determine tilt from the one or more overlay metrology measurements;
predict tilt with a simulator based on at least the determined tilt; and
determine one or more correctables for at least one of one or more lithography tools or the one or more metrology tools to adjust for the predicted tilt, wherein the one or more correctables are configured to reduce an amount of tilt in the sample or overlay inaccuracy of the one or more overlay metrology measurements.

2. The system of claim 1 , wherein the one or more correctables are provided to the one or more lithography tools as one or more control signals.

3. The system of claim 2 , wherein the one or more lithography tools is adjusted based on the one or more correctables to reduce the amount of tilt caused by an N+1 step of the sample.

4. The system of claim 2 , wherein the one or more lithography tools is adjusted based on the one or more correctables to reduce the amount of tilt caused by an N−1 step of the sample.

5. The system of claim 1 , wherein the one or more correctables are provided to the one or more metrology tools as one or more control signals.

6. The system of claim 5 , wherein the one or more metrology tools is adjusted based on the one or more correctables to reduce the overlay inaccuracy in the one or more overlay metrology measurements.

7. The system of claim 1 , wherein the one or more lithography tools include an etcher.

8. The system of claim 1 , wherein the one or more metrology tools include at least one of an electron-beam metrology tool or an optical metrology tool.

9. A system for error reduction in metrology measurements, comprising:
one or more metrology tools configured to hold a metrology sample; and
a controller communicatively coupled to the one or more metrology tools, wherein the controller includes one or more processors configured to execute program instructions causing the one or more processors to:
receive one or more overlay metrology measurements of one or more metrology targets of the metrology sample from the one or more metrology tools, wherein the one or more overlay metrology measurements are taken following an after develop inspection (ADI) process;
determine tilt from the one or more overlay metrology measurements;
predict tilt with a simulator based on at least the determined tilt; and
determine one or more correctables for at least one of one or more lithography tools or the one or more metrology tools to adjust for the predicted tilt, wherein the one or more correctables are configured to reduce an amount of tilt in the sample or overlay inaccuracy of the one or more overlay metrology measurements.

10. The system of claim 9 , wherein the one or more correctables are provided to the one or more lithography tools as one or more control signals.

11. The system of claim 10 , wherein the one or more lithography tools is adjusted based on the one or more correctables to reduce the amount of tilt caused by an N+1 step of the sample.

12. The system of claim 10 , wherein the one or more lithography tools is adjusted based on the one or more correctables to reduce the amount of tilt caused by an N−1 step of the sample.

13. The system of claim 9 , wherein the one or more correctables are provided to the one or more metrology tools as one or more control signals.

14. The system of claim 13 , wherein the one or more metrology tools are adjusted based on the one or more correctables to reduce the overlay inaccuracy in the one or more overlay metrology measurements.

15. The system of claim 9 , wherein the one or more lithography tools include an etcher.

16. The system of claim 9 , wherein the one or more metrology tools include at least one of an electron-beam metrology tool or an optical metrology tool.

17. A method comprising:
receiving one or more overlay metrology measurements of one or more metrology targets of a metrology sample from one or more metrology tools, wherein the one or more overlay metrology measurements are taken following an after develop inspection (ADI) process;
determining tilt from the one or more overlay metrology measurements;
predicting tilt with a simulator based on at least the determined tilt; and
determining one or more correctables for at least one of one or more lithography tools or the one or more metrology tools to adjust for the predicted tilt, wherein the one or more correctables are configured to reduce an amount of tilt in the sample or overlay inaccuracy of the one or more overlay metrology measurements.

18. The method of claim 17 , wherein the one or more correctables are provided to the one or more lithography tools as one or more control signals.

19. The method of claim 18 , wherein the one or more lithography tools is adjusted based on the one or more correctables to reduce the amount of tilt caused by an N+1 step of the sample.

20. The method of claim 18 , wherein the one or more lithography tools is adjusted based on the one or more correctables to reduce the amount of tilt caused by an N−1 step of the sample.

21. The method of claim 17 , wherein the one or more correctables are provided to the one or more metrology tools as one or more control signals.

22. The method of claim 21 , wherein the one or more metrology tools are adjusted based on the one or more correctables to reduce the overlay inaccuracy in the one or more overlay metrology measurements.

23. The method of claim 17 , wherein the one or more lithography tools include an etcher.

24. The method of claim 17 , wherein the one or more metrology tools include at least one of an electron-beam metrology tool or an optical metrology tool.

25. A system for tilt calculation based on overlay metrology measurements, comprising:
a controller communicatively coupled to one or more metrology tools configured to hold a metrology sample, wherein the controller includes one or more processors configured to execute program instructions causing the one or more processors to:
receive one or more overlay metrology measurements of one or more metrology targets of the metrology sample from the one or more metrology tools, wherein the one or more overlay metrology measurements are taken during an after etch inspection (AEI) process;
determine etch-induced tilt signature from the one or more overlay metrology measurements, wherein the etch-induced tilt signature is based on contrast precision measurements acquired from S-polarization measurements and contrast precision measurements acquired from P-polarization measurements; and
determine one or more correctables for at least one of one or more lithography tools or the one or more metrology tools to adjust for the determined etch-induced tilt signature, wherein the one or more correctables are configured to reduce an amount of tilt in the sample or overlay inaccuracy of the one or more overla

Assignees

• Kla Corp

Inventors

• Volkovich Roie
• Macdonald Paul
• Levy Ady
• Pei Jincheng
• Song Jinyan
• Manassen Amnon

Classifications

• G01N21/9501

  Semiconductor wafers (manufacturing processes per se of semiconductor devices implementing a measuring step H10P74/20) · CPC title

• G03F7/70633 Primary

  Overlay, i.e. relative alignment between patterns printed by separate exposures in different layers, or in the same layer in multiple exposures or stitching · CPC title

• G03F7/70616

  Monitoring the printed patterns · CPC title

• G03F7/7085

  Detection arrangement, e.g. detectors of apparatus alignment possibly mounted on wafers, exposure dose, photo-cleaning flux, stray light, thermal load · CPC title

• G03F7/705

  Modelling or simulating from physical phenomena up to complete wafer processes or whole workflow in wafer productions · CPC title