DEVICE HAVING PLASMA RADIATION SOURCE, METHOD OF FORMING RADIATION BEAM, AND LITHOGRAPHY DEVICE

PROBLEM TO BE SOLVED: To reduce damage caused on a mirror in a photolithography device which generates EUV radiation by using a plasma source.SOLUTION: A device for forming electromagnetic radiation includes a plasma radiation source (20), and a foil trap (24) provided with a plurality of thin foils (25) substantially extending in parallel with a radiation direction from a plasma radiation source (20). A grid (22) is disposed between the plasma radiation source (20) and the foil trap (24). A space is provided between the grid (22) and the foil trap (24). The device further includes an electrical potential applying circuit (28) for applying an electrical potential to the grid (22) so as to make the grid (22) repel electrons discharged by the plasma radiation source (20) and produce a positive space electrical charge between the grid (22) and the foil trap (24) to deflect ions discharged by the plasma radiation source (20) toward the foil trap.