Granted Patent B2

US 12,339,583 · App. 17/776,728 · Granted Jun 24, 2025

Inventors: Janardan Nath (Norwalk, CT); Christopher John Mason (Newtown, CT); Duan-Fu Stephen Hsu (Fremont, CA); Todd R. Downey (Monroe, CT); Tian Gang (Best, NL)

Assignees: ASML HOLDING N.V.; ASML NETHERLANDS B.V.

G03F1/70G03F1/36

Abstract

Claims (27)

1. A method associated with imaging a pattern, the method comprising:

determining a non-uniform illumination intensity profile for illumination from an illumination optical system; and

adjusting, by a hardware computer system, the pattern and the illumination based on the non-uniform illumination intensity profile until a termination condition is satisfied.

2. The method of claim 1 , wherein the determining and adjusting are performed as part of a source mask optimization.

3. The method of claim 1 , wherein the non-uniform illumination intensity profile is determined based on a population of empirical data and/or a corresponding electronic model.

4. The method of claim 1 , wherein the method is for a lithographic apparatus, the lithographic apparatus comprising the illumination optical system and projection optics configured to image the pattern onto a substrate;

wherein the non-uniform illumination intensity profile is determined based on the illumination optical system and the projection optics; and

wherein the method further comprises determining one or more adjustments for the projection optics based on the non-uniform illumination intensity profile until the termination condition is satisfied.

5. The method of claim 4 , wherein the lithographic apparatus comprises a slit, and wherein the non-uniform illumination intensity profile is a through slit non-uniform illumination intensity profile.

6. The method of claim 5 , wherein the lithographic apparatus comprises a pupil, and wherein the determining the one or more adjustments for one or more selected from: the pattern, the projection optics, or the illumination optical system comprises determining an adjustment for a through slit pupil.

7. The method of claim 4 , wherein the determining the one or more adjustments for one or more selected from: the pattern, the projection optics, or the illumination optical system comprises determining a through slit apodization.

8. The method of claim 4 , wherein determining the one or more adjustments for one or more selected from: the pattern, the projection optics, or the illumination optical system comprises performing optical proximity correction.

9. The method of claim 8 , wherein the performing optical proximity correction comprises applying one or more rule or model based assist features, and modeling a process for imaging the pattern onto the substrate.

10. The method of claim 9 , wherein a model for the modeling comprises a through slit optical proximity correction model configured to model the process for imaging the pattern onto the substrate using the non-uniform illumination intensity profile.

11. The method of claim 10 , wherein the through slit optical proximity correction model is configured to model the process for imaging the pattern onto the substrate using the non-uniform illumination intensity profile and different doses from the illumination optical system.

12. The method of claim 4 , further comprising adjusting for drift in the non-uniform illumination intensity profile; and

the determining the one or more adjustments for one or more selected from: the pattern, the projection optics, or the illumination optical system is based on a drift-adjusted non-uniform illumination intensity profile until the termination condition is satisfied.

13. The method of claim 12 , wherein the adjusting for drift comprises positioning one or more beam interceptors in one or more locations in a path of the illumination to intercept one or more corresponding portions of the illumination in the one or more locations.

14. The method of claim 12 , wherein the adjusting for drift comprises modeling a positioning of one or more beam interceptors in one or more locations in a path of the illumination to intercept one or more corresponding portions of the illumination in the one or more locations.

15. The method of claim 12 , wherein the drift is caused by projection optics collector contamination and/or illumination optical system tolerances.

16. The method of claim 4 , wherein the determining the one or more adjustments for one or more selected from: the pattern, the projection optics, or the illumination optical system based on the non-uniform illumination intensity profile is configured to reduce high frequency non-uniformity in the illumination from the illumination optical system relative to illumination from the illumination optical system having a substantially uniform illumination intensity profile.

17. The method of claim 4 , wherein the determining the one or more adjustments for one or more selected from: the pattern, the projection optics, or the illumination optical system comprises determining an adjustment for a through slit dipole X pupil.

18. The method of claim 4 , wherein the determining the one or more adjustments for one or more selected from: the pattern, the projection optics, or the illumination optical system are performed for a semiconductor manufacturing process.

19. The method of claim 18 , wherein the non-uniform illumination intensity profile is used for a pupil and mask co-optimization step of a source mask optimization for the semiconductor manufacturing process.

20. A computer program product comprising a non-transitory computer-readable medium having instructions therein, the instructions, when executed by a computer system, configured to cause the computer system to at least:

determine a non-uniform illumination intensity profile for illumination from an illumination optical system; and

adjust a pattern for imaging with the illumination and the illumination, based on the non-uniform illumination intensity profile until a termination condition is satisfied.

Assignments (2)

Continuity (2)

References Cited (24)