System and method for generating extreme ultraviolet light

1. A system comprising:

a laser beam apparatus configured to generate a laser beam; and

a target supply unit configured to supply a target material to be irradiated with the laser beam for generating extreme ultraviolet light, wherein

the laser beam apparatus is configured to:

generate a first pre-pulse laser beam with which the target material is irradiated, the first pre-pulse laser beam having a pulse duration of less than 1 ns, so as to make the target be diffused in a dome shape,

generate a second pre-pulse laser beam with which the target material irradiated with the first pre-pulse laser beam is irradiated, and

generate a main pulse laser beam with which the target material irradiated with the second pre-pulse laser beam is irradiated.

2. The system according to claim 1 , wherein the laser beam apparatus includes a CO 2 laser apparatus.

3. The system according to claim 1 , wherein the laser beam apparatus comprises:

a first laser apparatus configured to generate the first pre-pulse laser beam with which the target material is irradiated; and

a second laser apparatus configured to generate the second pre-pulse laser beam with which the target material irradiated with the first pre-pulse laser beam is irradiated, and the main pulse laser beam with which the target material irradiated with the second pre-pulse laser beam is irradiated.

4. The system according to claim 3 , wherein

the first laser apparatus is configured to generate a laser beam having a first wavelength, and

the second laser apparatus is configured to generate a laser beam having a second wavelength longer than the first wavelength.

5. The system according to claim 4 , wherein

the first laser apparatus is a YAG laser apparatus; and

the second laser apparatus is a CO 2 laser apparatus.

6. The system according to claim 1 , wherein the laser beam apparatus comprises:

a first laser apparatus configured to generate the first pre-pulse laser beam with which the target material is irradiated;

a second laser apparatus configured to generate the second pre-pulse laser beam with which the target material irradiated with the first pre-pulse laser beam is irradiated; and

a third laser apparatus configured to generate the main pulse laser beam with which the target material irradiated with the second pre-pulse laser beam is irradiated.

7. The system according to claim 6 , wherein

the first and second laser apparatuses are configured to generate laser beams each having a first wavelength, and

the third laser apparatus is configured to generate a laser beam having a second wavelength longer than the first wavelength.

8. The system according to claim 7 , wherein

the first laser apparatus is a first YAG laser apparatus;

the second laser apparatus is a second YAG laser apparatus; and

the third laser apparatus is a CO 2 laser apparatus.

9. The system according to claim 1 , wherein the laser beam apparatus comprises:

a first laser apparatus configured to generate the first pre-pulse laser beam with which the target material is irradiated and the second pre-pulse laser beam with which the target material irradiated with the first pre-pulse laser beam is irradiated; and

a second laser apparatus configured to generate the main pulse laser beam with which the target material irradiated with the second pre-pulse laser beam is irradiated.

10. The system according to claim 9 , wherein

the first laser apparatus is configured to generate a laser beam having a first wavelength, and

the second laser apparatus is configured to generate a laser beam having a second wavelength longer than the first wavelength.

11. The system according to claim 10 , wherein

the first laser apparatus is a YAG laser apparatus; and

the second laser apparatus is a CO 2 laser apparatus.

12. The system according to claim 10 , wherein

the first laser apparatus is a fiber laser apparatus; and

the second laser apparatus is a CO 2 laser apparatus.

13. The system according to claim 1 , further comprising a laser controller for the laser beam apparatus to control an output timing of the main pulse laser beam.

14. The system according to claim 13 , wherein the laser controller is configured to control the laser beam apparatus to output the main pulse laser beam in 0.3 μs to 3.0 μs after the target material is irradiated with the first pre-pulse laser beam.

15. The system according to claim 1 , wherein the laser beam apparatus includes a mode-locked laser apparatus.

16. The system according to claim 15 , wherein the mode-locked laser apparatus is a Ti:sapphire laser.

17. The system according to claim 15 , wherein the mode-locked laser apparatus is a fiber laser.