| 摘要 |
PROBLEM TO BE SOLVED: To effectively eliminate flying materials on an optical element without causing a decrease in the evaporation rate of clinging materials due to the floating of evaporated materials by causing the flying materials emitted from an X-ray and clinging to the optical element to be evaporated by heating of the optical element, and removing them using a gas flow. SOLUTION: A laser beam 200 is focused onto a target material 202 by a condensing lens 201 and converted into a plasma to radiate an X-ray plasma 203. An emitted material removing mechanism 204 is placed between the plasma 203 and an X-ray optical element by a holder 206 via a screw 205 and is controlled by a heater to a set temperature higher than that of the evaporated partial pressure of the optical element. The plasma 203 emits not only X-rays but also the target material and flying materials, which cling to the optical element. The clinging materials are heated by the heater, evaporated, and removed quickly by means of gas from a gas introducing pipe 210 so as to recover the performance of the optical element without decreasing the speed at which the target material evaporates from the surface of the optical element. |
