A proposal of high power EUV lithography illumination system using synchrotron radiation

A concept of a synchrotron radiation (SR) beam line and illumination system to be used for extreme-ultra-violet lithography (EUVL) is proposed. The SR in this case is bending radiation, and the electron energy of a storage ri ng is 500MeV, the bending magnetic field 1.5T, and the stored current 1A. T he radiation in 30 degrees is collected by 4 aspheric mirrors and brought t o a mask ring-field through 4 pieces of multi-layer mirrors and a grazing-i ncidence mirror. The total power for EUVL is 5.3W. The beam Line design inc luding vacuum system and radiation shielding structure is studied. The powe r level at the wafer can be as high as 15 mW/cm(2) depending on mirror coll ection efficiency and windows to be used.