Patent Number: 
Section: claims

1. An extreme ultraviolet light generation device for generating extreme ultraviolet light by irradiating a target with a pulse laser beam and thereby turning the target into plasma, comprising:a chamber;a magnet configured to form a magnetic field in the chamber; andan ion catcher including a collision unit disposed so that ions guided by the magnetic field collide with the collision unit, whereinthe collision unit includes a plurality of collision surfaces disposed to be inclined with respect to the magnetic field. 2. The extreme ultraviolet light generation device according to claim 1, further comprisinga collector mirror configured to reflect extreme ultraviolet light generated in the chamber and thereby concentrate the extreme ultraviolet light, whereinthe plurality of collision surfaces are disposed to be inclined toward an upstream side of the extreme ultraviolet light reflected by the collector mirror. 3. The extreme ultraviolet light generation device according to claim 1, whereinthe ion catcher includes a tubular member having a first end and a second end,the first end has an opening in a direction along the magnetic field,the collision unit is disposed between the first end and the second end, andthe collision unit includes first and second collision units disposed near the first end and the second end, respectively. 4. The extreme ultraviolet light generation device according to claim 1, whereinthe ion catcher includes a tubular member having a first end and a second end,the first end has an opening in a direction along the magnetic field,the collision unit is disposed between the first end and the second end, andthe ion catcher is configured to satisfy a relationship L/φ>3.55, where L is the length of the tubular member from the first end to the second end and φ is the maximum diameter of the opening of the tubular member. 5. The extreme ultraviolet light generation device according to claim 1, whereinthe ion catcher includes a tubular member having a first end and a second end,the first end has an opening in a direction along the magnetic field,the collision unit is disposed between the first end and the second end, andthe tubular member has a polygonally-columnar shape. 6. The extreme ultraviolet light generation device according to claim 1, whereinthe ion catcher includes a tubular member having a first end and a second end,the first end has an opening in a direction along the magnetic field,the collision unit is disposed between the first end and the second end,the magnet is an electromagnet including a coil, andat least a part of the tubular member is disposed in a bore of the coil. 7. The extreme ultraviolet light generation device according to claim 1, whereinthe ion catcher includes a tubular member having a first end and a second end,the first end has an opening in a direction along the magnetic field,the collision unit is disposed between the first end and the second end, andat least a part of the tubular member is disposed to project outside from the chamber. 8. An extreme ultraviolet light generation device for generating extreme ultraviolet light by irradiating a target with a pulse laser beam and thereby turning the target into plasma, comprising:a chamber;a magnet configured to form a magnetic field in the chamber; andan ion catcher including a collision unit disposed so that ions guided by the magnetic field collide with the collision unit; andan exhaust pump, whereinthe ion catcher includes a tubular member having a first end and a second end,the first end has an opening in a direction along the magnetic field,the collision unit is disposed between the first end and the second end, andthe exhaust pump is connected between the first end and the second end to exhaust gas out of the tubular member. 9. The extreme ultraviolet light generation device according to claim 8, wherein the collision unit includes conical or polygonally-pyramidal surfaces. 10. The extreme ultraviolet light generation device according to claim 8, whereinthe collision unit includes first and second collision units disposed near the first end and the second end, respectively. 11. The extreme ultraviolet light generation device according to claim 8, whereinthe ion catcher is configured to satisfy a relationship L/φ>3.55, where L is the length of the tubular member from the first end to the second end and φ is the maximum diameter of the opening of the tubular member. 12. The extreme ultraviolet light generation device according to claim 8, whereinthe tubular member has a polygonally-columnar shape. 13. The extreme ultraviolet light generation device according to claim 8, whereinthe magnet is an electromagnet including a coil, andat least a part of the tubular member is disposed in a bore of the coil. 14. The extreme ultraviolet light generation device according to claim 8, whereinat least a part of the tubular member is disposed to project outside from the chamber. 15. An extreme ultraviolet light generation device for generating extreme ultraviolet light by irradiating a target with a pulse laser beam and thereby turning the target into plasma, comprising:a chamber;a magnet configured to form a magnetic field in the chamber; andan ion catcher including a collision unit disposed so that ions guided by the magnetic field collide with the collision unit, whereinthe ion catcher includes a tubular member having a first end and a second end,the first end has an opening in a direction along the magnetic field,the collision unit is disposed between the first end and the second end, andthe tubular member has a tapered shape. 16. The extreme ultraviolet light generation device according to claim 15, whereinthe collision unit includes first and second collision units disposed near the first end and the second end, respectively. 17. The extreme ultraviolet light generation device according to claim 15, whereinthe ion catcher is configured to satisfy a relationship L/φ>3.55, where L is the length of the tubular member from the first end to the second end and φ is the maximum diameter of the opening of the tubular member. 18. The extreme ultraviolet light generation device according to claim 15, wherein the collision unit includes conical or polygonally-pyramidal surfaces. 19. The extreme ultraviolet light generation device according to claim 15, whereinthe magnet is an electromagnet including a coil, andat least a part of the tubular member is disposed in a bore of the coil. 20. The extreme ultraviolet light generation device according to claim 15, whereinat least a part of the tubular member is disposed to project outside from the chamber.