EP0154797B1 - Verfahren zur Herstellung von Vielkanalplatten und deren Verwendung - Google Patents

Verfahren zur Herstellung von Vielkanalplatten und deren Verwendung Download PDF

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Publication number
EP0154797B1
EP0154797B1 EP85101038A EP85101038A EP0154797B1 EP 0154797 B1 EP0154797 B1 EP 0154797B1 EP 85101038 A EP85101038 A EP 85101038A EP 85101038 A EP85101038 A EP 85101038A EP 0154797 B1 EP0154797 B1 EP 0154797B1
Authority
EP
European Patent Office
Prior art keywords
multichannel
plate
channels
plates
positive
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP85101038A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0154797A3 (en
EP0154797A2 (de
Inventor
Erwin Prof. Dr. Becker
Wolfgang Dr. Ehrfeld
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Forschungszentrum Karlsruhe GmbH
Original Assignee
Kernforschungszentrum Karlsruhe GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kernforschungszentrum Karlsruhe GmbH filed Critical Kernforschungszentrum Karlsruhe GmbH
Priority to AT85101038T priority Critical patent/ATE37757T1/de
Publication of EP0154797A2 publication Critical patent/EP0154797A2/de
Publication of EP0154797A3 publication Critical patent/EP0154797A3/de
Application granted granted Critical
Publication of EP0154797B1 publication Critical patent/EP0154797B1/de
Expired legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J43/00—Secondary-emission tubes; Electron-multiplier tubes
    • H01J43/04—Electron multipliers
    • H01J43/06—Electrode arrangements
    • H01J43/18—Electrode arrangements using essentially more than one dynode
    • H01J43/24—Dynodes having potential gradient along their surfaces
    • H01J43/246—Microchannel plates [MCP]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/02—Manufacture of electrodes or electrode systems
    • H01J9/12—Manufacture of electrodes or electrode systems of photo-emissive cathodes; of secondary-emission electrodes
    • H01J9/125—Manufacture of electrodes or electrode systems of photo-emissive cathodes; of secondary-emission electrodes of secondary emission electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2201/00—Electrodes common to discharge tubes
    • H01J2201/32—Secondary emission electrodes

Definitions

  • the invention relates to a method for producing multi-channel plates for amplifying optical images or other areal signal distributions by means of secondary electron multiplication, and to the use of a stack of multi-channel plates produced by this method.
  • multi-channel image intensifier plate also name: channel multiplier plate, multi- or micro-channel plate. It consists of an approximately 1 mm thick glass plate enclosed in an evacuated vessel, which is penetrated perpendicularly or obliquely to the surface by many closely adjacent channels of approximately 30 micrometers in diameter. Through the use of glasses containing lead oxide and a post-treatment with reducing gases at elevated temperature, the inner surfaces of the channels are rendered weakly electrically conductive. By applying a voltage of approximately 1000 volts between the metal-coated surfaces of the plate, a potential gradient is generated in the channels, whereby each channel is given the properties of a secondary electron multiplier.
  • An inclination of the channels favors the collision of the primary particles with the channel walls and thus the desired electron release.
  • it enables the construction of a plate stack with a zigzag-shaped channel structure that suppresses the undesired acceleration of parasitic ions.
  • a similar effect can be achieved by a weak curvature of the channels.
  • metal core process a fine, uniform wire is coated with heated glass and wrapped around a polygonal drum. Individual blocks are cut out of the winding and the glass coatings of the wires are melted together. The block is then cut into thin slices, from which the wire cores are removed by etching.
  • a major disadvantage of the metal core process described is seen in the fact that the metal cores and thus the channels have uniform diameters, but their distances differ greatly from one another.
  • fine parallel grooves are etched into the surfaces of thin glass plates by photolithography.
  • the plates are stacked so that the grooves of plates lying on top of one another together form the desired channels.
  • the plates are melted into blocks from which the multi-channel plates are then cut.
  • This method is supported by the fact that the distance between the grooves can be precisely regulated during the photolithographic etching. You can also use this method to make the channels relatively slightly curved or zigzag.
  • the width and depth of the grooves can hardly be controlled during the etching and the melting process. The result is that the multichannel plates distort the image so much during amplification that the process had to be abandoned.
  • multi-channel plates are usually manufactured using the so-called double-drawing process: hollow glass cylinders or glass cylinders filled with a more soluble glass are drawn out into glass threads, which are bundled, fused and further drawn out, after which the processes of bundling and fusing are repeated. The final bundle is cut into approximately 1 mm thick plates, from which the cores of easily soluble glass, which have been pulled down to a diameter of approximately 30 11 m, are removed. With the double drawing process, too, certain variations in the cross sections and positions of the channels have to be accepted due to the manufacturing principle.
  • the scatter in the cross sections and positions of the channels in the previously known multi-channel plates prevents or complicates the exact assignment of other optical and / or electrical components produced using methods of microfabrication to individual channels or channel groups of the image intensifier. However, such an assignment is important, for example, for the separate electrical further processing of the electrical currents supplied by the individual channels or channel groups.
  • the scatter in the cross sections and positions of the channels in the previously known multi-channel plates is also responsible for the fact that the resolution of the plate stack with a zigzag-shaped channel structure mentioned above results in considerable losses in resolution.
  • Layered multi-channel plates for image intensifiers with dynodes in the form of perforated dynode plates are known from DE-OS 31 50 257 and DE-PS 2414658, in which photo-etching technology is proposed as the preferred method for producing the channel system.
  • the dynode material e.g. a BeCu alloy, etched.
  • This technique good results are achieved in practice if the diameter of the channels and the thickness of the dynode are approximately the same (see column 3, lines 5 to 10 of DE-PS 24 14 658).
  • the photoetching technique can no longer be used with the desired success. (see also Spectrum of Science, Jan. 1982, page 53, left column, lines 26ff.).
  • the object of the invention is a method for producing multi-channel plates of the generic type and their
  • the thickness of the plates can be a multiple of the channel diameter.
  • the cross-sectional shapes and the positions of the individual channels can be specified with a tolerance of the order of magnitude of one micrometer, even in the case of relatively thick multi-channel plates.
  • the method also has the advantage that it has a particularly large ratio of the sum of the channel cross-sectional areas to the total area of the plate, i.e. a particularly high transparency of the multi-channel plate can be achieved.
  • Both corpuscular rays and electromagnetic waves in particular the X-rays (synchrotron radiation) generated by an electron synchrotron, can be considered as high-energy radiation. While one uses masks in a known manner when using electromagnetic waves to produce the desired structures, the structure can also be generated by electromagnetic control when using corpuscular beams.
  • the material for the production of the multichannel positive forms according to claim 1 or the primary multichannel positive forms according to claim 2 depends on the type of high-energy radiation, corresponding regulations, for example, can be found in DE-PS 29 22 642 and DE-OS 32 21 981.
  • the metallic multi-channel negative mold is produced by galvanic molding of the multi-channel positive mold connected to a metal electrode.
  • the metal electrode can be used as the base plate of the metallic multi-channel negative mold.
  • it is also possible to continue the galvanic deposition of metal until the multichannel positive form is covered by a continuous metal layer which, optionally after smoothing its surface, is used as the base plate of the metallic multichannel negative form.
  • a suitable choice of the electrode material possibly in connection with a passivation of its surface, can prevent the electroplating from adhering to the electrode in a known manner. It is then possible to separate the multichannel positive mold, including the electrode connected to it, from the generated multichannel negative mold without damage, which makes repeated use of the multichannel positive mold possible.
  • the glass containing lead oxide used to manufacture the previously known multi-channel plates can be used to fill the metallic multi-channel negative mold.
  • the glass can be melted or sintered in using glass powder.
  • other electrically non-conductive or only weakly conductive materials for example Al 2 O 3 powder, can also be used for filling, which can also be sintered together at a higher temperature to form a dimensionally stable body.
  • the aftertreatment with H 2 which is customary in the case of lead oxide-containing glasses may have to be carried out by another aftertreatment, for. B. can be replaced by the known CVD method ( «Chemical vapor deposition»).
  • the method of the invention can be modified in accordance with claim 2, details of which can be found, for example, in DE-PS 32 06 820.4.
  • Non-adhesive reactive resins are particularly suitable as impression materials.
  • multi-channel plates produced according to the invention with channels inclined to the plate surface can also be assembled in stacks in such a way that zigzag channel structures result. While in the case of stacking known multichannel plates, losses in spatial resolution have to be accepted due to the inevitable scatter in the cross sections and positions of the channels, the stacking in the multichannel plates produced according to the invention can be carried out by mutually aligning the channel openings while largely avoiding this disadvantage.
  • FIG. 1 to 7 schematically show the individual steps in the manufacture of a multi-channel plate
  • FIG. 8 schematically shows in perspective the structure of a stack of multi-channel plates.
  • a 0.5 mm thick plate 1 made of polymethyl methacrylate (PMMA) is used as the starting material for the production of the multichannel positive mold, which is firmly adhered to a metal base plate 2 made of an iron-nickel alloy and serving as an electrode.
  • the PMMA plate 1 is irradiated with synchrotron radiation 3 via an X-ray mask, which is directed obliquely to the surfaces of the PMMA plate and the X-ray mask.
  • the X-ray mask consists of a carrier 4, which only weakly absorbs the X-radiation, and a grid-like absorber 5, which strongly absorbs the X-radiation, by means of which the cross-sectional shapes and the positions of the channels are specified.
  • the PMMA is chemically changed in the areas 6 not covered by the absorber due to the high-intensity parallel synchronous radiation.
  • the irradiated areas 6 are made by introducing the PMMA into a developer Solution removed so that a multi-channel positive shape 7 with channel-shaped openings 8 according to FIG.
  • a mixture of a substance from the glycol ether group, a substance from the primary amines and water and a substance from the azine group according to DE-OS 3039110 is used as the developer solution.
  • the channel-shaped openings 8 have a hexagonal cross-sectional shape with a width of approximately 30 11 m, the thickness of the walls 8 a is approximately 3 ⁇ m.
  • an iron-nickel alloy is electrodeposited into the channel-shaped openings 8, column-like structures 9 being formed from this alloy on the electrically conductive base plate 2 in the grid-shaped multi-channel positive form 7.
  • the multichannel positive form is then removed by dissolving it in a solvent, so that a metallic negative form of the multichannel plate according to FIG. 5 is exposed.
  • the spaces 10 between the columnar structures 9 of the metallic negative form are filled with a lead glass melt 11 under vacuum (FIG. 6).
  • a lead glass melt 11 under vacuum FOG. 6
  • the iron-nickel alloy mentioned above it can be ensured that the lead glass and the alloy have approximately the same thermal expansion coefficients, so that the stresses that occur during cooling do not lead to crack formation in the glass.
  • the structure consisting of glass 11 and metal 9 is finally ground, and the metal 9 is removed by dissolving it in a selective etching.
  • the multi-channel plate provided with the openings 12 is finally covered in a known manner by sputtering metal on both sides with thin conductive layers 13, while the inner surfaces of the channels are made weakly conductive by heating in hydrogen (FIG. 7).
  • the primary metallic negative shape which corresponds to the shape shown in FIG. 5, is filled with a reaction resin which does not adhere to the metal as an impression material beyond the columnar structures of the metallic negative shapes.
  • the reaction resin has hardened, the secondary multichannel positive form formed therefrom and the primary metallic negative form are separated from one another, whereupon the secondary multichannel positive form is firmly attached with the side having the openings to a metallic base plate serving as an electrode.
  • the secondary multichannel positive form closed on the top is then removed to such an extent that the channel openings are exposed.
  • Subsequent galvanic molding produces secondary metallic negative shapes, which in turn correspond to the shape shown in FIG. 5.
  • the production of the multi-channel plate is continued in accordance with the production steps already explained with reference to FIGS. 6 and 7.
  • the secondary multichannel positive molds made from the reaction resin can also be repeatedly electroplated.
  • a thin release agent film is applied in a known manner by immersion in a release agent solution.

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Electron Tubes For Measurement (AREA)
  • Paper (AREA)
  • Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)
EP85101038A 1984-03-10 1985-02-01 Verfahren zur Herstellung von Vielkanalplatten und deren Verwendung Expired EP0154797B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85101038T ATE37757T1 (de) 1984-03-10 1985-02-01 Verfahren zur herstellung von vielkanalplatten und deren verwendung.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19843408848 DE3408848A1 (de) 1984-03-10 1984-03-10 Verfahren zur herstellung von vielkanalplatten
DE3408848 1984-03-10

Publications (3)

Publication Number Publication Date
EP0154797A2 EP0154797A2 (de) 1985-09-18
EP0154797A3 EP0154797A3 (en) 1986-12-30
EP0154797B1 true EP0154797B1 (de) 1988-10-05

Family

ID=6230128

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85101038A Expired EP0154797B1 (de) 1984-03-10 1985-02-01 Verfahren zur Herstellung von Vielkanalplatten und deren Verwendung

Country Status (6)

Country Link
US (1) US4563250A (pt)
EP (1) EP0154797B1 (pt)
JP (1) JPS60208041A (pt)
AT (1) ATE37757T1 (pt)
BR (1) BR8501058A (pt)
DE (1) DE3408848A1 (pt)

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3841621A1 (de) * 1988-12-10 1990-07-12 Draegerwerk Ag Elektrochemische messzelle mit mikrostrukturierten kapillaroeffnungen in der messelektrode
DE69030145T2 (de) * 1989-08-18 1997-07-10 Galileo Electro Optics Corp Kontinuierliche Dünnschicht-Dynoden
US5189777A (en) * 1990-12-07 1993-03-02 Wisconsin Alumni Research Foundation Method of producing micromachined differential pressure transducers
US5206983A (en) * 1991-06-24 1993-05-04 Wisconsin Alumni Research Foundation Method of manufacturing micromechanical devices
US5190637A (en) * 1992-04-24 1993-03-02 Wisconsin Alumni Research Foundation Formation of microstructures by multiple level deep X-ray lithography with sacrificial metal layers
US5378583A (en) * 1992-12-22 1995-01-03 Wisconsin Alumni Research Foundation Formation of microstructures using a preformed photoresist sheet
EP0872331A1 (en) 1997-04-16 1998-10-21 Matsushita Electric Industrial Co., Ltd. Stamper protecting layer for optical disk molding apparatus, optical disk molding apparatus and optical disk molding method using the stamper protecting layer
US6521149B1 (en) * 2000-06-06 2003-02-18 Gerald T. Mearini Solid chemical vapor deposition diamond microchannel plate
DE10305427B4 (de) * 2003-02-03 2006-05-24 Siemens Ag Herstellungsverfahren für eine Lochscheibe zum Ausstoßen eines Fluids
US7154086B2 (en) * 2003-03-19 2006-12-26 Burle Technologies, Inc. Conductive tube for use as a reflectron lens
US20080073516A1 (en) * 2006-03-10 2008-03-27 Laprade Bruce N Resistive glass structures used to shape electric fields in analytical instruments

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4031423A (en) * 1969-04-30 1977-06-21 American Optical Corporation Channel structure for multi-channel electron multipliers and method of making same
GB1434053A (en) * 1973-04-06 1976-04-28 Mullard Ltd Electron multipliers
FR2434480A1 (fr) * 1978-08-21 1980-03-21 Labo Electronique Physique Dispositif multiplicateur d'electrons a galettes de microcanaux antiretour optique pour tube intensificateur d'images
DE2922642C2 (de) * 1979-06-02 1981-10-01 Kernforschungszentrum Karlsruhe Gmbh, 7500 Karlsruhe Verfahren zum Herstellen von Platten für den Aufbau von Trenndüsenelementen
DE3039110A1 (de) * 1980-10-16 1982-05-13 Siemens AG, 1000 Berlin und 8000 München Verfahren fuer die spannungsfreie entwicklung von bestrahlten polymethylmetacrylatschichten
DE3150257A1 (de) * 1981-12-18 1983-06-30 Siemens AG, 1000 Berlin und 8000 München Bildverstaerker
DE3206820C2 (de) * 1982-02-26 1984-02-09 Kernforschungszentrum Karlsruhe Gmbh, 7500 Karlsruhe Verfahren zum Herstellen von Trenndüsenelementen
DE3221981C2 (de) * 1982-06-11 1985-08-29 Kernforschungszentrum Karlsruhe Gmbh, 7500 Karlsruhe Verfahren zum Herstellen von aus Trennkörpern mit Abschlußplatten bestehenden Trenndüsenelementen zur Trennung gas- oder dampfförmiger Gemische

Also Published As

Publication number Publication date
JPH0552618B2 (pt) 1993-08-05
JPS60208041A (ja) 1985-10-19
US4563250A (en) 1986-01-07
BR8501058A (pt) 1985-10-29
EP0154797A3 (en) 1986-12-30
DE3408848A1 (de) 1985-09-19
EP0154797A2 (de) 1985-09-18
DE3408848C2 (pt) 1987-04-16
ATE37757T1 (de) 1988-10-15

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