JP2011141176A - Electron beam irradiator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electron beam irradiator which can irradiate an object with an electron beam like a curtain. <P>SOLUTION: When a voltage between an emitter 14 and a gate electrode 15 and that between a grid electrode 19 and a metal film (anode) 18 are set at a few kV and about 40 kV, an electron beam 16 is emitted from the emitter 14, and the electron beam 16 is directed by the electrode 15, diaphragmed by the grid electrode 19 and applied outward from a window 17 like a curtain. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a straight tube type electron beam irradiation apparatus.

As a means for curing a resist solution applied to the surface of a semiconductor wafer or glass substrate or curing a printing plate, a polymerization initiator by UV (ultraviolet rays) is contained in the resist solution or the printing plate. However, since the UV curing method is accompanied by deterioration of the material, it has recently been considered to cure by electron beam irradiation.

An electron beam is generated by applying a high voltage between the emitter (cathode) and the anode in a vacuum. X-rays are generated when the anode is a target such as tungsten.

Patent Document 1 discloses a configuration in which an emitter is attached to one surface of an enclosure via an insulator. Patent Document 2 discloses that an emitter (carbon-based electron emission material) is inserted into a groove formed in a face plate, A configuration in which a gate electrode is provided is disclosed.

JP 2007-305565 A International Publication No. 2007/135812

In both Patent Documents 1 and 2, when a straight tube tube made of glass is not used and it is desired to irradiate electrons linearly using a conventional electron beam irradiation device, one end of the tube is used as an electron beam irradiation window. A plurality of irradiation devices are arranged along the line, and there are problems in terms of cost and maintenance.

Further, in Patent Document 1, there are no gate electrodes on both sides of the emitter, and it is impossible to efficiently irradiate an electron beam from the window portion. If the emitter is put in the groove portion as in Patent Document 2, the groove portion A charge-up occurs at the corner of this, which cannot be eliminated by providing a gate electrode.

  In order to solve the above-mentioned problems, in the present invention, in an electron beam irradiation apparatus in which an emitter for emitting an electron beam is disposed in a tube maintained in a reduced pressure atmosphere, the tube is a straight tube type tube made of glass and a plurality of tubes are used. And the emitter is a rod-shaped nanocarbon electrode, and the inner surface of the tube forming the window is formed by penetrating along the length of the tube and being hermetically closed with a metal film from the outside. It is arranged along the length direction of the tube at a position close to the inner surface of the tube opposite to the tube, and a bar shape is formed along the length direction of the tube at a position close to the inner surface of the tube facing the window portion on both sides of the emitter. The gate electrode is arranged, and the grid electrode is arranged between the emitter and the window.

  With the above configuration, the direction of the electron beam generated at the emitter is determined by the gate electrode, is narrowed by the grid electrode, and is emitted in a linear shape (curtain shape) from the window portion.

The electron beam irradiation apparatus according to the present invention can be used not only for curing the coating solution but also for sterilization (sterilization). Also in this case, not the point irradiation but the electron beam can be irradiated with a certain width, so that the efficiency is good.

In addition to the above, the electron beam irradiation apparatus according to the present invention is advantageous in food processing and pharmaceutical manufacturing because there is almost no temperature rise of about 5 ° C. without material deterioration, coloring, and odor such as gamma rays and UV. .

In addition, the electron beam has a shorter sterilization (sterilization) treatment time (about 1/10) compared to gamma rays and UV, and the electron beam penetrates the substance, so that it can be processed in the final packaging state. Furthermore, since sterilization (sterilization) determination can be performed with the irradiation amount (dose) of an electron beam, a separate inspection becomes unnecessary.

Side view of glass substrate transfer line to which electron beam irradiation apparatus according to the present invention is applied The perspective view of the electron beam irradiation apparatus which concerns on this invention Sectional drawing of the electron beam irradiation apparatus which concerns on this invention (A) is the expanded sectional view of the principal part of the electron beam irradiation apparatus which concerns on this invention, (b) is the figure which looked at (a) from the bottom. The perspective view which shows the positional relationship of the emitter of the electron beam irradiation apparatus which concerns on this invention, a gate electrode, and a grid electrode Enlarged photo of nanocarbon electrode surface as emitter The same figure as FIG. 3 which shows another embodiment

  In FIG. 1, an electron beam irradiation apparatus 11 according to the present embodiment is a straight tube. The straight tube is made of glass such as Pyrex (registered trademark).

  The electron beam irradiation device 11 is covered with a protective case 12 at the top and side of a straight tube, and the transport line is configured by arranging a large number of rollers 100 in parallel. A glass substrate (semiconductor wafer) is placed on the rollers 100. W is conveyed.

  From the electron beam irradiation apparatus 11, the resist solution applied on the glass substrate (semiconductor wafer) W is irradiated with an electron beam in a curtain shape to cure the resist solution.

As shown in FIGS. 2 and 3, the electron beam irradiation apparatus 11 has an emitter 14 inserted in a tube 13 maintained in a reduced pressure state (1 to 10 ⁻⁶ Torr). The emitter 14 has a nanocarbon layer formed on the surface of a rod-shaped electrode such as stainless steel. As shown in FIG. 6, the nanocarbon layer has a sharp tip, and a large amount of electrons are easily emitted from the tip.

  In order to form a nanocarbon layer as shown in FIG. 6, CH4 + H2 gas is introduced into a plasma atmosphere, CH4 is activated by plasma, and a nanocarbon layer is formed on the substrate surface.

  Further, on both sides of the emitter 14, rod-shaped gate electrodes 15 and 15 are arranged to control the width of the electron beam 16 emitted from the emitter 14. As the gate electrode 15, another gate electrode 15 for preventing charge-up may be disposed behind the emitter 14 as shown in FIG.

  A plurality of window portions 17 are formed through the tube 13 along the length direction of the tube 13 and are hermetically closed with a metal film (anode) 18 from the outside. The bar-shaped emitter 14 is disposed along the length of the tube at a position close to the inner surface of the tube 13 facing the inner surface of the tube 13 forming the window portion 17, and the gate electrode 15 is located on both sides of the emitter on the window. It is disposed along the length direction of the tube at a position close to the inner surface of the tube facing the portion 17.

  The diameter of the window portion 17 is 200 to 800 μm, the thickness of the tube 13 is 0.5 to 1.0 mm, the thickness of the metal film (anode) 18 is smaller than the thickness of the tube 13, and the thickness in the tube 13 is not broken. Is secured.

A grid electrode 19 is disposed between the emitter 14 and gate electrodes 15 and 15 and the window portion 17. As shown in FIG. 5, the grid electrode 19 has a plate shape and is formed with slits 20 for narrowing the electron beam in the length direction.

In the above, a voltage of −40 kV to −70 kV is applied to the emitter 14, and a voltage of −20 kV to −70 kV is applied so as to obtain a current required for the gate electrode 15 for current control from the emitter 14.

The grid electrode 19 functions as an electric field lens, and serves to prevent electrons from being irradiated outside the region of the window portion 17. For this purpose, a voltage of 0 (ground) to -10 kV is applied. The electrons focused by the grid electrode 19 pass through the thin Be window 17 as they are and are emitted to the outside air. Therefore, almost no X-rays are generated by the focused electrons.

In addition, the slit 20 of the grid electrode 19 is appropriately sized, and a lens effect is created by applying a bias voltage, whereby a controlled electron beam (curtain shape) is irradiated onto the object.

  The electron beam irradiation apparatus according to the present invention can be used in semiconductor (electronic circuit) manufacturing processes, food and chemical sterilization (sterilization) processes, and the like.

DESCRIPTION OF SYMBOLS 11 ... Electron beam irradiation apparatus, 12 ... Protective case, 13 ... Tube, 14 ... Emitter, 15 ... Gate electrode, 16 ... Electron beam, 17 ... Window part, 18 ... Metal film (anode), 19 ... Grid electrode, 20 ... Slit, 100 ... roller, W ... glass substrate (semiconductor wafer).

Claims (1)

In an electron beam irradiation apparatus in which an emitter that emits an electron beam is disposed in a tube maintained in a reduced-pressure atmosphere, the tube is a glass straight tube, and a plurality of windows are arranged in the length direction of the tube. And the emitter is a rod-shaped nanocarbon electrode that is close to the tube inner surface facing the tube inner surface forming the window portion. A gate electrode arranged in a rod shape along the length of the tube is disposed along the length of the tube, and at a position near the inner surface of the tube facing the window on both sides of the emitter. An electron beam irradiation apparatus, wherein a grid electrode is disposed between the window part and the window part.

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