Gas Electron Multiplier and Manufacturing Method for Gas Electron Multiplication Foil Used for Same as Well as Radiation Detector Using Gas Electron Multiplier

• US 20090084972A1
• Filed: 03/01/2007
• Published: 04/02/2009
• Est. Priority Date: 03/02/2006
• Status: Active Grant

• Current Assignee: Riken, SCIenergy, Inc., University of Tokyo
• Original Assignee: Riken, SCIenergy, Inc., University of Tokyo
• Inventors: Hamagaki, Hideki, Tamagawa, Toru, Koshimuta, Satoshi
• Granted Patent: US 7,994,483 B2
• Time in Patent Office: Days
• US Class Current: 250/374
• CPC Class Codes: G01T 1/18 with counting-tube arrangements, e.g. with Geiger counters tubes H01J47/08; with alarm provision G01T7/125
• CPC Class Codes: H01J 3/025 Electron guns using a discharge in a gas or a vapour as electron source gas-filled discharge tubes with gaseous cathodes H01J15/00
• CPC Class Codes: H01J 47/02 Ionisation chambers

Abstract

To attain objects to reduce the spread of electrons as compared with a conventional one without degrading the multiplication factor of electrons; to provide a large electron multiplication factor; and to improve positional resolution, there is provided a gas electron multiplier using interaction between radiation and gas through photoelectric effects including: a chamber filled with gas and a single gas electron multiplication foil arranged in the chamber wherein the gas electron multiplication foil is made of a plate-like multilayer body composed by having a plate-like insulation layer made of a macromolecular polymer material having a thickness of around 100 μm to 300 μm and flat metal layers overlaid on both surfaces of the insulation layer, and the plate-like multilayer body is provided with a through-hole structure.

Claims

1. A gas electron multiplier using interaction between radiation and gas through photoelectric effects, comprising:

a chamber filled with gas; and

a single gas electron multiplication foil arranged in the said chamber, wherein

the said gas electron multiplication foil is made of a plate-like multilayer body composed of a plate-like insulation layer made of a macromolecular polymer material having a thickness of 100 mm to 300 mm and flat metal layers overlaid on both surfaces of the said insulation layer, and

the said plate-like multilayer body is provided with a through-hole structure.

4. A radiation detector utilizing a gas electron multiplier using interaction between radiation and gas through photoelectric effects, wherein

the said gas electron multiplier is the gas electron multiplier according to claim 1.

2. A gas electron multiplier using interaction between radiation and gas through photoelectric effects, comprising:

a chamber filled with gas; and

a single gas electron multiplication foil arranged in the said chamber, wherein

the said gas electron multiplication foil is made of a plate-like multilayer body which is composed of a multilayer body where multiple plate-like insulation layers made of a macromolecular polymer material are stacked with a flat metal layer sandwiched in between and flat metal layers overlaid on both surfaces of said multilayer body, and

the said plate-like multilayer is provided with a through-hole structure.

3. The gas electron multiplier according to claim 2, wherein

the total thickness of the said multiple insulation layers is 100 mm to 600 mm.

7. A radiation detector utilizing a gas electron multiplier using interaction between radiation and gas through photoelectric effects, wherein

the said gas electron multiplier is the gas electron multiplier according to claim 2.

8. A radiation detector utilizing a gas electron multiplier using interaction between radiation and gas through photoelectric effects, wherein

the said gas electron multiplier is the gas electron multiplier according to claim 3.

5. A manufacturing method for a gas electron multiplication foil used in a gas electron multiplier using interaction between radiation and gas through photoelectric effects, comprising:

overlaying flat metal layers on both surfaces of a plate-like insulation layer made of a macromolecular polymer material having a thickness of 100 mm to 300 mm;

etching the said metal layers to a predetermined pattern;

removing the said insulating film through irradiation with a laser beam applied perpendicularly to the plane of the said metal layers in accordance with the said predetermined pattern;

creating a through-hole extending in the direction perpendicular to the plane of the said metal layers; and

carrying out a desmear process using plasma and a chemical on surfaces of the said metal layers and a wall surface of the through-hole in the said insulation layers.

6. A manufacturing method for a gas electron multiplication foil used in a gas electron multiplier using interaction between radiation and gas through photoelectric effects, comprising:

overlaying flat metal layers on both surfaces of a plate-like insulation layer made of a macromolecular polymer material having a thickness of 50 mm to 300 mm;

etching the said metal layers to a predetermined pattern;

stacking a resultant of overlaying a flat metal layer on one surface of a plate-like insulation layer, which is made of a macromolecular polymer material having a thickness of 50 mm to 300 mm, on one or both surfaces of the said metal layers;

etching outermost metal layers of the resultant obtained in the stacking step in accordance with the said predetermined pattern;

removing all of the said insulating films through irradiation with a laser beam applied perpendicularly to the plane of said outermost metal layers in accordance with the said predetermined pattern;

creating a through-hole extending in the direction perpendicular to the plane of the metal layers on the said outermost surfaces; and

carrying out a desmear process using plasma and a chemical on surfaces of the said metal layers and a wall surface of the through-hole in the said insulation layers.