EXTREME-ULTRAVIOLET LIGHT SOURCE

PROBLEM TO BE SOLVED: To provide an extreme-ultraviolet light source device capable of maintaining a desired thickness of a high temperature plasma material on a discharge electrode, even if rotary operation and stop of a discharge electrode are repeated.SOLUTION: An extreme-ultraviolet light source device includes a thickness adjustment section for adjusting the thickness of a high temperature plasma material on the curved surface of a disc-like discharge electrode to have a predetermined thickness. The thickness adjustment section includes a thickness adjustment member (skimmer) 30a disposed oppositely to the curved surface of the discharge electrode 21a via a predetermined gap, an energization member (spring) 32a for urging the thickness adjustment member 30a in a direction approaching the curved surface, and a regulation member (stopper) 33a for regulating the movement of the thickness adjustment member 30a in the urging direction by the energization member 32a, so that the gap between the curved surface and the thickness adjustment member 30a does not become narrower than a gap corresponding to the desired thickness.SELECTED DRAWING: Figure 3 【課題】放電電極の回転動作の停止と稼動とが繰り返されても、放電電極上の高温プラズマ原料の厚みを所望の厚みに維持することができる極端紫外光光源装置を提供する。【解決手段】極端紫外光光源装置は、円盤状の放電電極の曲面上の高温プラズマ原料の膜厚が所定の膜厚となるよう調整する膜厚調整部を備える。膜厚調整部は、放電電極２１ａの曲面と所定の間隙を介して対向配置する膜厚調整部材（スキマー）３０ａと、膜厚調整部材３０ａを曲面に接近する方向に付勢する付勢部材（バネ）３２ａと、曲面と膜厚調整部材３０ａとの間隙が所望の膜厚に相当する間隙よりも狭くならないように、付勢部材３２ａによる付勢方向における膜厚調整部材３０ａの移動を規制する規制部材（ストッパ）３３ａと、を備える。【選択図】図３