PLASMA LIGHT SOURCE

PROBLEM TO BE SOLVED: To provide a plasma light source capable of suppressing intensity decrease of extreme UV light and a load of maintenance due to debris in a plasma light source provided with a pair of coaxial electrodes.SOLUTION: A plasma light source includes: a pair of coaxial electrodes 10 and 10 that are arranged facing with each other with a symmetrical surface sandwiched therebetween, generate plasma, and confine the same; a laser device for irradiating laser light to a holding part 14 of a plasma medium; a collecting mirror 50 for condensing extreme UV light radiated from the plasma between the pair of coaxial electrodes; and debris shielding means (debris shielding plate) 60 that shields the plasma medium radiated from the holding part 14 between the external electrode 12 and the collecting mirror 50.SELECTED DRAWING: Figure 1 【課題】一対の同軸状電極を備えるプラズマ光源において、デブリによる極端紫外光の強度低下とメンテナンスの負担を抑制する。【解決手段】プラズマ光源は、対称面を挟んで互いに対向配置され、プラズマを発生し、閉じ込める一対の同軸状電極１０、１０と、プラズマ媒体の保持部１４にレーザー光を照射するレーザー装置と、一対の同軸状電極間のプラズマから放射された極端紫外光を集光する集光ミラー５０と、保持部１４から放出されるプラズマ媒体を外部電極１２と集光ミラー５０との間で遮蔽するデブリ遮蔽手段（デブリ遮蔽板）６０とを備える。【選択図】図１