JP2013228332A - Manufacturing method of particle beam transmission window, and particle beam transmission window - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain high transmittance by reducing loss due to a frame of a particle beam while avoiding the breaking of a foil film due to atmospheric pressure or pressure fluctuation, to thereby manufacture a transmission window excellent in airtightness and strength.SOLUTION: A particle beam transmission window 10 includes a foil film 12 transmitting a particle beam, and a frame 14 that is brought into close contact with the foil film 12 and in which a minute through-hole 14a is formed into a mesh shape. A manufacturing method of the particle beam transmission window 10 includes: a first step of coating a metal 14c at least on the surface of the foil film side of the frame 14; a second step of irradiating the coating surface and the joint surface of the foil film 12 with an inactive element, an ion beam 16 thereof, plasma or an electron beam for activation; and a third step of pressurizing the foil film 12 and the frame 14 at room temperature to join them.

Description

  The present invention relates to a method of manufacturing a particle beam transmission window and a particle beam transmission window, and more particularly, charged particle beams such as electron beams and ion beams, electromagnetic waves such as X rays and gamma rays while avoiding damage due to atmospheric pressure and pressure fluctuations. The present invention relates to a method for manufacturing a particle beam transmission window capable of high particle beam transmittance, and the particle beam transmission window manufactured by the manufacturing method.

  Conventionally, a transmission window as shown in Patent Documents 1 and 2 is used when X-rays are taken out from a vacuum chamber. The outline is shown in FIG. The transmission window 2 is a beryllium foil that is a metal thin film. The transmission window 2 is joined to the opening 1 a of the vacuum vessel 1 with brazing materials 4 and 5, or diffusion-bonded, and the atmosphere side is stopped with a protective ring 3. For this reason, the transmission window 2 can irradiate X-rays from the inside to the outside of the vacuum container 1 with high transmittance while keeping the vacuum state of the vacuum container 1 good.

  In order to reinforce such a transmission window, Patent Document 3 discloses that a straight side bar made of a high melting point material is formed on the vacuum side surface of the particle beam transmission window and is inclined with respect to the moving direction of the irradiated object. A plurality of reinforcing bars, one end of the reinforcing bar is fixed to the water-cooled holding plate by brazing, and the other end of the reinforcing bar is slidably inserted into a loose-fitting hole provided in the water-cooled holding plate. Have been described.

JP-A-6-260121 (FIG. 1) Japanese Patent Laid-Open No. 6-251736 (FIG. 1) JP 2002-14200 A JP-A-9-10963 JP 2008-207221 A

  However, in the vacuum brazing or diffusion bonding described in Patent Documents 1 and 2, cracks and breakage occur even in a foil film having a thickness of 10 to 100 μm due to thermal deformation and stress due to the heating temperature at the time of bonding. Therefore, heat bonding with a thin foil having a thickness of several μm has a high heat load and cannot be applied. Further, the reinforcing bar described in Patent Document 3 has a problem that it is insufficient for suppressing the burst due to the atmospheric pressure applied to the window.

  On the other hand, Patent Documents 4 and 5 describe a room temperature bonding method in which bonding is performed at room temperature without heating, but application to a particle beam transmission window targeted by the present invention has not been considered.

  The present invention has been made to solve the above-mentioned conventional problems, while avoiding the destruction of the foil film due to atmospheric pressure and pressure fluctuation, while reducing the loss due to the particle beam frame, to achieve a high transmittance, It is an object of the present invention to manufacture a transmission window excellent in airtightness and strength.

  The present invention provides at least a foil film of the above-mentioned frame in the production of a particle beam transmission window comprising a foil film that transmits particle beams and a frame that is in close contact with the foil film and has fine mesh holes formed in a mesh shape. A first step of coating the surface of the metal with a metal, and a second step of irradiating the coating surface and the bonding surface of the foil film with an inert element, its ion beam, plasma or electron beam for activation. A third step of pressing and bonding the foil film and the frame at room temperature to solve the above problems by a method for manufacturing a particle beam transmission window.

  Here, in the first step, the surface of the foil film on the frame side can be coated with metal.

  Moreover, it can have the 4th process of removing the metal coated by the surface by the side of the said foil film in a vacuum.

  In the first step, the metal foil can be coated on the surface of the foil film on the frame side by masking the permeable foil film portion.

  Further, the first step and the second step can be performed on both side surfaces of the foil film.

  The present invention also provides a particle beam transmission window produced by any one of the production methods described above.

  According to the present invention, since the foil film is sandwiched between the frames in which the fine through-holes are formed in a mesh shape, the loss of the particle beam due to the frame is reduced while avoiding the destruction of the foil film due to atmospheric pressure and pressure fluctuations. In addition, high transmittance can be realized. Also, after coating the metal on the bonding surface, it was activated by irradiation with an inert element, its ion beam, plasma or electron beam, and the foil film and the frame were pressed at room temperature to bond the whole. Even with a foil film having a thickness of μm, it is possible to manufacture a transmission window having excellent airtightness and strength.

Cross-sectional view of the principal part showing the configuration of the conventional example of the radiation transmitting window described in Patent Documents 1 and 2 (A) top view and (b) cross-sectional view showing the configuration of an embodiment of a particle beam transmission window according to the present invention The flowchart which shows the manufacturing method of the particle beam transmission window which concerns on this invention Sectional view showing the process Sectional drawing which shows the example of the electron beam irradiation apparatus by which the particle beam transmission window is arrange | positioned

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  In the embodiment in which the present invention is applied to the electron beam transmitting window 10, as shown in FIG. 2, 37 honeycomb-shaped unit windows 11 are arranged in a honeycomb shape, and a foil film 12 that transmits an electron beam, and the foil The frame 12 is provided with a plurality of minute through-holes 14a formed in a mesh shape to sandwich the membrane 12 from above and below in the figure.

  The foil film 12 is made of titanium having a thickness of 2 to 5 μm, for example, and the frame 14 is made of stainless steel having a thickness of 0.1 to 0.5 mm, for example. The material of the frame 14 may be titanium, nickel, aluminum, copper, an alloy thereof, beryllium, carbon, or the like.

  Hereinafter, the manufacturing procedure will be described with reference to FIG.

  First, in step 100, as shown in FIG. 4A, a thin metal, for example, gold having a thickness of about 0.1 to 10 μm is formed on the surface of the frame 14 on the side of the foil film 12 according to the surface state. A metal coating 14c is formed by coating by plating, vapor deposition, or the like. Silver, copper, aluminum or the like may be used instead of gold.

  Similarly, a metal coating 12c is formed on the surface of the foil film 12 on the frame 14 side by coating a metal film having a thickness of about 5 to 50 nm according to the surface state. The metal coating 12c can be the same as the metal coating 14c. Since the metal coating 12c deposited on the foil film 12 has an action of stopping the electron beam, it is desirable that the thickness is thin, and it is omitted when sufficient bonding strength can be obtained due to the material, surface flatness, pressure, etc. It is also possible.

Next, at step 110, as shown in FIG. 4B, an inert element such as argon, xenon, krypton, its ion beam 16, plasma or electron beam is applied to the metal coatings 12c, 14c, for example, 10 ⁻⁶ Pa. After evacuation, it is activated by irradiation for several minutes and cleaned.

Next, in step 120, as shown in FIG. 4C, the bonding is performed by pressing at, for example, 80 to 400 to 3000 kgf / cm ² at room temperature, depending on the material and surface flatness. The pressurization may be performed only on the periphery, but the entire pressurization improves the overall strength and is stable, and can be used only on one side frame.

  Finally, in step 130, as shown in FIG. 4D, the transmission window is placed in a vacuum beam or plasma irradiation apparatus and irradiated with the beam or plasma, and the metal coating 12c on the surface of the foil film 12 in the transmission window is formed by sputtering. Is removed by evaporation, and an uncoated portion is formed to form a permeable foil film portion 12d. If the thickness of the metal coating 12c is about 5 to 50 nm, it can be easily removed, and it can also be applied by applying an inert gas beam or plasma irradiation at room temperature bonding or by irradiating an electron beam with an actual electron beam irradiation device. It is.

According to the above procedure, the tensile strength of the joint is estimated to be 10 MPa or more as the transmission window performance, and the vacuum tightness is 1 × 10 ⁻⁶ Pa · m ³ / sec at the He leak rate.

  The electron beam transmission window 10 is used by being disposed between the vacuum chamber 22 and the atmosphere as illustrated in FIG. In the figure, 24 is a cathode, 26 is an anode, and 28 is an electron beam.

  In the above embodiment, the metal coating 12c is also applied to the surface of the foil film 12 on the frame 14 side. However, since the coated metal film greatly impairs the electron beam that passes through the foil film 12, the metal film 12c It is desirable to make the thickness of the coating 12c thinner than the foil film 12, or to coat the foil film 12 by masking the transmissive foil film part 12d during coating. When masking the permeable foil film portion 12d, the thickness of the metal coating 12c may be about 0.1 to 10 μm, which is the same as the surface of the frame 14 on the foil film 12 side.

  In the above embodiment, the frame 14 is provided on both sides of the foil film 12, but it is also possible to have only one side if necessary.

  Further, in the above embodiment, 37 unit windows 11 each having the fine pores 14a formed in the honeycomb shape are arranged in the honeycomb shape, but the arrangement state of the fine pores 14a is not limited to the honeycomb shape, and unit The number of windows and the arrangement state are not limited to this. Further, the fine through holes may be uniformly formed as a whole without being divided into unit windows.

  The application target is not limited to the electron beam transmission window, and can be generally applied to particle beams.

DESCRIPTION OF SYMBOLS 10 ... Electron beam transmission window 12 ... Foil film 12c, 14c ... Metal coating 12d ... Transmission foil film part (non-coating part)
14 ... Frame 14a ... Micro through-hole 16 ... Beam 28 ... Electron beam

Claims (6)

When manufacturing a particle beam transmission window comprising a foil film that transmits particle beams, and a frame that is in close contact with the foil film and has fine mesh holes formed in a mesh shape.
A first step of coating a metal on at least the surface of the frame on the foil film side;
A second step of irradiating the coating surface and the bonding surface of the foil film with an inert element, its ion beam, plasma or electron beam,
A third step of joining the foil film and the frame by pressurizing at normal temperature;
A method for producing a particle beam transmission window, comprising:   2. The method for producing a particle beam transmissive window according to claim 1, wherein in the first step, a metal is also coated on the surface of the foil film on the frame side. 3.   The method for producing a particle beam transmissive window according to claim 2, further comprising a fourth step of removing the metal coated on the surface of the foil film on the frame side in a vacuum.   2. The method for producing a particle beam transmissive window according to claim 1, wherein in the first step, the surface of the foil film on the frame side is coated with a metal by masking the permeable foil film part. 3.   5. The method for producing a particle beam transmissive window according to claim 1, wherein the first step and the second step are performed on both side surfaces of the foil film.   A particle beam transmission window manufactured by the manufacturing method according to claim 1.

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