| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a radiation source having a contamination barrier for reducing a deposition rate of ions, atoms, molecules, granular debris and the like on a collector mirror of an EUV radiation source. <P>SOLUTION: A radiation source includes a plasma formation portion, at which fuel comes into contact with a radiation beam to form a plasma. A collector with a mirror collects and reflects EUV radiation generated at a first focal point toward a second focal point. A contamination barrier is positioned so that a peripheral edge of the contamination barrier does not block more than 50% of a solid angle defined by a mirror at the second focal point, and thereby, the EUV radiation reflected by the collector mirror passes through the contamination barrier and is not attenuated excessively. The contamination barrier functions to trap fuel materials such as ions, atoms, molecules or nano droplets from the plasma, so as to prevent them from being accumulated on the collector mirror. A gas extraction port may be provided near the plasma formation portion to restrain diffusion of the fuel debris and contamination toward the collector mirror. <P>COPYRIGHT: (C)2013,JPO&INPIT |
