Apparatus for correcting photomask and method thereof

Patent metadata

Field	Value
Publication number	US-12366799-B2
Application number	US-202217899616-A
Country	US
Kind code	B2
Filing date	Aug 31, 2022
Priority date	Dec 30, 2021
Publication date	Jul 22, 2025
Grant date	Jul 22, 2025

Abstract

A photomask correction method capable of increasing the photomask precision is provided. The photomask correction method comprises measuring an intensity profile of a laser, acquiring etching amount data corresponding to the measured intensity profile using a library, determining a process parameter of the laser based on the etching amount data, and correcting a photomask with the laser according to the determined process parameter.

First claim

What is claimed is:

1. A method for correcting a photomask comprising:
measuring an intensity profile of a laser,
acquiring etching amount data corresponding to the measured intensity profile using a library,
determining a process parameter of the laser based on the etching amount data, and
correcting a photomask with the laser according to the determined process parameter.

2. The method of claim 1 , wherein measuring the intensity profile of the laser comprises,
irradiating the laser to a beam profiler, and acquiring an intensity profile through the beam profiler.

3. The method of claim 1 , wherein correcting the photomask with the laser comprises,
forming a liquid film by a chemical solution on the photomask,
wherein the photomask includes a first region and a second region that are different from each other,
wherein a liquid film in the first region is not heated by the laser, and a liquid film in the second region is heated by the laser.

4. The method of claim 3 , wherein the photomask further includes a third region,
wherein a liquid film in the second region is heated by the laser for a first irradiation time,
wherein a liquid film in the third region is heated by the laser for a second irradiation time longer than the first irradiation time.

5. The method of claim 1 , wherein the process parameter includes at least one of a laser irradiation time, a chemical solution concentration, and an interval between a laser and a photomask.

6. The method of claim 1 further comprises,
generating the library before measuring an intensity profile of the laser,
wherein generating the library comprises,
irradiating a first laser to a beam profiler, and acquiring a first intensity profile of the first laser through the beam profiler,
correcting the photomask with the first laser,
analyzing the corrected photomask to acquire a first etching amount generated in the photomask, and
liberalizing the first intensity profile and the first etching amount.

7. The method of claim 6 , wherein acquiring the first intensity profile of the first laser through the beam profiler comprises,
acquiring a first image of the first laser through the beam profiler,
dividing the first image into a plurality of first pixels, and
acquiring an intensity from each of the plurality of first pixels to acquire a first intensity profile in units of pixels.

8. The method of claim 6 , wherein analyzing the corrected photomask comprises,
acquiring a second image from the corrected photomask using an electron microscope,
dividing the second image into a plurality of pixels, and
acquiring an etching amount from each of the plurality of second pixels to acquire the first etching amount in units of pixels.

9. The method of claim 1 , wherein measuring the intensity profile of the laser is performed while a laser generator irradiating the laser stands by at a home port,
wherein the photomask enters into a process chamber while the laser generator stands by at a home port.

10. A method for correcting a photomask comprising:
measuring an intensity profile of a laser provided from a laser generator using a beam profiler installed in a home port while the laser generator stands by at the home port,
forming a liquid film by supplying a chemical solution onto a photomask including a first region and a second region,
acquiring etching amount data corresponding to the measured intensity profile by using a library including a plurality of intensity profiles and a plurality of etching amount data corresponding to the plurality of intensity profiles,
determining an irradiation time of the laser based on the etching amount data, and
heating a liquid film in the second region with the laser for the determined irradiation time without heating a liquid film in the first region.

11. The method of claim 10 , wherein the photomask further comprises a third region,
wherein determining the irradiation time of the laser based on the etching amount data comprises,
determining that a liquid film in the second region is heated for a first irradiation time, and a liquid film in the third region is heated for a second irradiation time longer than the first irradiation time.

12. The method of claim 10 further comprises,
generating the library before measuring an intensity profile of the laser,
wherein generating the library comprises,
irradiating a first laser to a beam profiler, and acquiring a first intensity profile of the first laser through the beam profiler,
correcting the photomask with the first laser,
analyzing the corrected photomask to acquire a first etching amount generated in the photomask, and
liberalizing the first intensity profile and the first etching amount.

13. The method of claim 12 , wherein acquiring the first intensity profile of the first laser through the beam profiler comprises,
acquiring a first image of the first laser through the beam profiler,
dividing the first image into a plurality of first pixels,
acquiring an intensity from each of the plurality of first pixels to acquire a first intensity profile in units of pixels,
wherein analyzing the corrected photo mask comprises,
acquiring a second image from the corrected photomask using an electron microscope,
dividing the second image into a plurality of pixels, and
acquiring an etching amount from each of the plurality of second pixels to acquire the first etching amount in units of pixels.

14. An apparatus for correcting a photomask comprising:
a process chamber;
a support unit installed in the process chamber and for supporting a photomask;
a chemical solution supply unit installed in the process chamber and for supplying a chemical solution to the photomask to form a liquid film;
a laser module installed in the process chamber and including a laser generator for irradiating a laser to the liquid film;
a home port for measuring an intensity profile of the laser, in which the laser generator stands by;
a storage unit for storing a library including a plurality of intensity profiles and a plurality of etching amount data corresponding to the plurality of intensity profiles; and
a controller for acquiring etching amount data corresponding to the measured intensity profile using the library, determining a process parameter of the laser based on the etching amount data, and correcting a photomask with the laser according to the determined process parameter.

15. The apparatus of claim 14 , wherein a beam profiler is installed in the home port, the laser is irradiated to the beam profiler, and the intensity profile of the laser is acquired through the beam profiler.

16. The apparatus of claim 14 , wherein the photomask includes a first region and a second region that are different from each other,
wherein a liquid film in the first region is not heated by the laser, and a liquid film in the second region is heated by the laser.

17. The apparatus of claim 16 , wherein the photomask further includes a third region,
wherein a liquid film in the second region is heated by the laser for a first irradiation time,
wherein a liquid film in the third region is heated by the laser for a second irradiation time longer than the first irradiation time.

18. The apparatus of claim 14 , wherein the process parameter includes at least one of a laser irradiation time, a chemical solution concentration, and an interval between a laser and a photomask.

19. The apparatus of claim 14 , wherein measuring the intensity profile of the laser is performed while the laser g

Assignees

• Semes Co Ltd

Inventors

• Yang Hyo Won
• Yoon Hyun
• Jeong Ji Hoon
• Jung In Ki
• Choi Ki Hoon
• Kim Tae Hee
• Oh Se Hoon

Classifications

• G03F7/70025

  by lasers · CPC title

• G03F7/70558

  Dose control, i.e. achievement of a desired dose · CPC title

• G03F1/80

  Etching · CPC title

• G01J2001/4261

  Scan through beam in order to obtain a cross-sectional profile of the beam · CPC title

• G01J1/4257

  applied to monitoring the characteristics of a beam, e.g. laser beam, headlamp beam (monitoring arrangements for lasers in general H01S3/0014) · CPC title