Extreme UV light generation device

Patent metadata

Field	Value
Publication number	US-10512149-B2
Application number	US-201816214435-A
Country	US
Kind code	B2
Filing date	Dec 10, 2018
Priority date	Jul 20, 2016
Publication date	Dec 17, 2019
Grant date	Dec 17, 2019

Abstract

An extreme UV light generation device may include: a chamber having a plasma generation region at an inside of the chamber, the chamber receiving a target substance externally supplied to the plasma generation region; an outlet port provided on the chamber; a magnetic field generating unit configured to generate a magnetic field to converge cations on the outlet port, the cations being generated from the target substance that has been turned into plasma in the plasma generation region; an electron emission unit configured to emit electrons neutralizing the cations; and an exhaust tube joined to the outlet port and through which a neutralized substance obtained by neutralizing the cations flows.

First claim

What is claimed is:

1. An extreme UV light generation device comprising:
a chamber having a plasma generation region at an inside of the chamber, the chamber receiving a target substance externally supplied to the plasma generation region;
an outlet port provided on the chamber;
a magnetic field generating unit configured to generate a magnetic field to converge cations on the outlet port, the cations being generated from the target substance that has been turned into plasma in the plasma generation region;
an electron emission unit configured to emit electrons neutralizing the cations; and
an exhaust tube joined to the outlet port and through which a neutralized substance obtained by neutralizing the cations flows.

2. The extreme UV light generation device according to claim 1 , wherein
the outlet port is provided in a range which electrons emitted from the electron emission unit reach.

3. The extreme UV light generation device according to claim 1 , wherein
in the chamber, a collector mirror is provided, the collector mirror being configured to reflect and focus, on a focal point, extreme ultraviolet light generated from the target substance that has been turned into plasma in the plasma generation region, and
the electron emission unit is placed on an outer side of a region surrounded by the focal point, an outermost light beam of a light flux focused on the focal point, and a reflection plane of the collector mirror.

4. The extreme UV light generation device according to claim 1 , wherein
the electron emission unit is placed on a wall of the chamber near the outlet port or a wall of the exhaust tube near the outlet port.

5. The extreme UV light generation device according to claim 1 , wherein
the magnetic field generating unit is configured of a pair of magnets opposite to each other as the magnets sandwich the chamber, and
the electron emission unit is placed on a chamber side from a position where magnetic flux density is highest.

6. The extreme UV light generation device according to claim 1 , wherein
the magnetic field generating unit is configured of a magnet placed on an outside of the chamber,
the exhaust tube is inserted into a through hole provided on the magnet, and
the electron emission unit is placed in an inside of the exhaust tube inserted into the through hole.

7. The extreme UV light generation device according to claim 1 , wherein
the exhaust tube has a bend that is bent in a direction crossing an opening face of the outlet port, and
at the bend, a turning member is provided, the turning member having a curved surface configured to change a traveling direction of the neutralized substance guided from the outlet port to a direction crossing the opening face of the outlet port.

8. The extreme UV light generation device according to claim 7 , wherein
the turning member is configured of a material that emits secondary electrons due to collision of the cations.

9. The extreme UV light generation device according to claim 8 , wherein
the electron emission unit is configured to emit electrons from the turning member.

10. The extreme UV light generation device according to claim 7 , wherein
the electron emission unit is configured to emit electrons from the turning member.

11. The extreme UV light generation device according to claim 1 , wherein
in an inside of the exhaust tube, a backflow prevention member is provided, the backflow prevention member being configured to reduce a backflow of the neutralized substance, and
the backflow prevention member is configured in which an inside part is narrower toward an exhaust direction of the exhaust tube.

12. The extreme UV light generation device according to claim 1 , wherein
in an inside of the exhaust tube, a trapping member is provided, the trapping member being configured to trap the neutralized substance, and
the trapping member includes a heater configured to heat and precipitate the neutralized substance.

13. The extreme UV light generation device according to claim 12 , wherein
the heater is removably mounted on an inner wall of the exhaust tube.

Assignees

• Gigaphoton Inc

Inventors

• Hori Tsukasa
• Okazaki Shinji

Classifications

• G03F7/20

  Exposure; Apparatus therefor (photographic printing apparatus for making copies G03B27/00) · CPC title

• G03F7/70

  Microphotolithographic exposure; Apparatus therefor (photo-masks G03F1/00) · CPC title

• G21K1/06

  using diffraction, refraction or reflection, e.g. monochromators (G21K1/10, G21K7/00 take precedence) · CPC title

• G21K1/14

  using charge exchange devices, e.g. for neutralising or changing the sign of the electrical charges of beams (producing or accelerating neutral particle beams H05H3/00) · CPC title

• H05G2/008 Primary

  involving an energy-carrying beam in the process of plasma generation · CPC title