| abstract |
The present invention provides a method of emitting EUV light at a low cost, which can obtain a higher conversion efficiency into EUV light than before by using a laser beam, can reduce the amount of debris generation than conventional ones. . A method of emitting EUV light by a double pulse irradiation method in which a target material is irradiated with a prepulse laser beam to generate plasma and then irradiated with a main pulse laser beam to emit EUV light. The material is made of at least one of tin and a tin compound, the ion density of plasma generated by irradiation with the prepulse laser beam is 1 × 10 16 to 1 × 10 19 cm −3 , and the main pulse laser beam is in the infrared region Of emitting EUV light, which is a laser beam. [Selection] Figure 1 |