| 摘要 |
The present invention relates to a method of increasing the operation lifetime of an optical collector unit (3, 6) arranged in an irradiation device. The irradiation device at least comprises a radiation source (1) emitting optical radiation, in particular extreme ultraviolet radiation or soft X-rays, said radiation source (1) generating substances and/or particles colliding with optical surfaces of the optical collector unit (3, 6), which forms a radiation beam of a portion of said radiation emitted by said radiation source (1), and a debris mitigation unit (37) arranged between the radiation source (1) and said optical collector unit (3, 6). In the proposed method the optical collector unit (3, 6) is moved during operation and/or in operation pauses of the device such that deposits or degradation effects caused by collision of said substances and/or particles with said optical surfaces of the collector unit (3, 6) are distributed more homogeneously on said optical surfaces than without such a movement. With the method and the corresponding device the optical surfaces of the collection unit are degraded more homogeneously resulting in an increased lifetime of the collector unit. |
