| 摘要 |
PROBLEM TO BE SOLVED: To improve precision in exposure, by suppressing change in optical constant of a phase shifter material of a phase shift mask caused by irradiation of exposure light. SOLUTION: This device has a configuration such that a half tone type phase shift mask 8 where a desired pattern is formed is irradiated with ArF laser beam, and a pattern of the mask 8 is transferred on to a wafer 15. In this case, the mask 8 is set in a mask housing part 20 isolated from the atmosphere. Here, the mask housing part 20 is held in a nitrogen atmosphere containing oxygen, while an oxygen partial pressure to the entire gas pressure is set to 5%. |
