Method for improving OPC modeling

• US 6,934,929 B2
• Filed: 01/13/2003
• Issued: 08/23/2005
• Est. Priority Date: 01/13/2003
• Status: Expired due to Fees

• Current Assignee: Bell Semiconductor, LLC (Hilco Inc. (d/b/a Hilco Global))
• Original Assignee: LSI Logic Corporation (Broadcom, Inc.)
• Inventors: Bailey, George, Brist, Travis
• Primary Examiner(s): Smith, Matthew
• Assistant Examiner(s): Kik, Phallaka
• Application Number:
  US10/341,119
• Publication Number:
  US 20040139420A1
• Time in Patent Office: 953 Days
• Field of Search: 716/21, 378/35, 382/144, 382/154, 382/16, 382/170, 382/190, 382/165, 250/311, 702/40, 702/72, 702/172, 700/110, 700/121
• US Class Current: 716/53
• CPC Class Codes: G03F 1/36 Masks having proximity correction features; Preparation thereof, e.g. optical proximity correction [OPC] design processes
• CPC Class Codes: G03F 1/68 Preparation processes not covered by groups G03F1/20 - G03F1/50
• CPC Class Codes: G03F 7/70441 Optical proximity correction [OPC]
• CPC Class Codes: G03F 7/70608 Monitoring the unpatterned workpiece, e.g. measuring thickness, reflectivity or effects of immersion liquid on resist
• CPC Class Codes: G03F 7/70625 Dimensions, e.g. line width, critical dimension [CD], profile, sidewall angle or edge roughness
• CPC Class Codes: G03F 7/70641 Focus

Abstract

The invention provides a method for OPC modeling. The procedure for tuning a model involves collecting cross-section images and critical dimension measurements through a matrix of focus and exposure settings. These images would then run through a pattern recognition system to capture top critical dimensions, bottom critical dimensions, resist loss, profile and the diffusion effects through focus and exposure.

Claims

1. A method of tuning a model comprising the steps of:

a) collecting cross-section images of a resist profile, wherein each image includes a top surface, a bottom surface and sides of the resist profile;

b) running said cross-section images through a pattern recognition system; and

c) capturing resultant data.

2. A method as defined in claim 1, wherein said cross-section images, top critical dimension measurements and bottom critical dimension measurements are collected through a matrix of focus and exposure setting.

3. A method as defined in claim 2, wherein said matrix of focus comprises negative focuses.

4. A method as defined in claim 3, wherein said negative focuses include −

0.60 micrometers, −

0.45 micrometers, −

0.30 micrometers and −

0.15 micrometers.

5. A method as defined in claim 2, wherein said matrix of focus comprises positive focuses.

6. A method as defined in claim 5, wherein said positive focuses comprise 0.15 micrometers, 0.30 micrometers, 0.45 micrometers, and 0.60 micrometers.

7. A method as defined in claim 2, wherein said matrix of focus comprises a best focus.

8. A method as defined in claim 7, wherein said best focus is 0.00 micrometers.

9. A method as defined in claim 1, wherein said resultant data comprises top critical dimensions.

10. A method as defined in claim 1, wherein said resultant data comprises bottom critical dimensions.

11. A method as defined in claim 1, wherein said resultant data comprises resist loss.

12. A method as defined in claim 1, wherein said resultant data comprises profile.

13. A method as defined in claim 1, wherein said resultant data comprises diffusion effects through focus.

14. A method as defined in claim 1, wherein said cross-section images are collected by cleaving a wafer.

15. A method as defined in claim 1, wherein said cross-section images are collected through a use of a focused ion beam.