EP0542737A1 - Source de rayonnement synchrotron - Google Patents

Source de rayonnement synchrotron

Info

Publication number
EP0542737A1
EP0542737A1 EP90911616A EP90911616A EP0542737A1 EP 0542737 A1 EP0542737 A1 EP 0542737A1 EP 90911616 A EP90911616 A EP 90911616A EP 90911616 A EP90911616 A EP 90911616A EP 0542737 A1 EP0542737 A1 EP 0542737A1
Authority
EP
European Patent Office
Prior art keywords
synchrotron radiation
radiation source
source according
magnet
path
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.)
Withdrawn
Application number
EP90911616A
Other languages
German (de)
English (en)
Inventor
Frank Anton
Andreas Jahnke
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.)
Siemens AG
Original Assignee
Siemens AG
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 Siemens AG filed Critical Siemens AG
Publication of EP0542737A1 publication Critical patent/EP0542737A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H13/00—Magnetic resonance accelerators; Cyclotrons
    • H05H13/04—Synchrotrons

Definitions

  • the invention relates to a sy ⁇ chrotron radiation source with a beam guidance system for accelerating and storing a particle beam of electrons or positrons on a closed path.
  • Synchrotron radiation sources of this type using, inter alia, magnets formed from superconducting winding arrangements, are not only intended for a variety of applications in physical research, but are also used as X-ray sources for the purposes of lithography, in particular in semiconductor chip production.
  • Synchrotron radiation arises when a particle beam of electrons or positrons is deflected from a straight path.
  • the particle beam is guided (stored) in a beam guidance system on a closed path, and the synchrotron radiation that is generated in the deflection magnets necessary for the curvature of the path is used.
  • the path should be curved with the smallest possible radius of curvature; this requires relatively high magnetic fields, which can only be produced economically with superconducting magnets.
  • Sy ⁇ chrotron radiation sources with superconducting magnets are, for. B. described in EP-C-0 208 163, EP-A-0 277 521 and DE-A-31 48 100.
  • the synchrotron radiation source consists of an electron storage ring with a superconducting magnet system.
  • Such a synchrotron radiation source is particularly compact, but the actual implementation is difficult due to the very limited space. Accordingly, EP-A-0 208 163 proposes that
  • Beam guidance system for the electron beam not ring-shaped form, but to provide two spaced apart superconducting deflection magnets, whereby the
  • Particle track receives a "racetrack" shape with two straight track sections in which devices for accelerating as well as for injecting and / or extracting the particles can be arranged. Further developments of such a synchrotron radiation source can be found, for example, in EP-A-0 277 521.
  • DE-A-31 48 100 and EP-A-0 277 521 are also references to the formation of a synchrotron radiation source for use in processes such as X-ray lithography and X-ray microscopy, in particular with regard to the choice of the energy of the particles to be stored and the corresponding design of the magnets , refer to.
  • a synchrotron radiation source for use in processes such as X-ray lithography and X-ray microscopy, in particular with regard to the choice of the energy of the particles to be stored and the corresponding design of the magnets , refer to.
  • the use of synchrotron radiation sources for the production of integrated circuits or the like with structures in the submicron range is an important industrial area of application.
  • the problematic handling of the superconducting magnets can be seen as possibly disadvantageous in the known configurations;
  • the mechanical design of the magnets has to meet the highest requirements, which entails correspondingly high manufacturing costs
  • the superconducting magnets are subjected to current which varies over time (such as is necessary when accelerating a particle beam to a predetermined energy ), very difficult, among other things due to the resulting eddy currents in the holding structures of the magnets.
  • Deflection magnets which can also be called mirror magnets, are used e.g. B. described in the article "Achromatic Magnetic Mirror for Ion Bea s" by H. A. Enge, Rev. Be. Instr. 34. (1963) 385.
  • a beam guidance system according to the
  • GB-A-2 015 821 is not suitable for storing a particle beam for long periods of time; the particle beam is lost in the beam guidance system after a few revolutions, if it has not previously been extracted for transmission.
  • the object of the present invention is to provide a synchrotron radiation source with a beam guiding system which both accelerates and stores a particle beam of electrons or for a longer period of time
  • a synchrotron radiation source which has a beam guiding system for storing a particle beam of electrons or positrons on a closed path, the beam guiding system containing at least one approximately achromatic mirror magnet which is formed from superconducting winding arrangements and in which the path is approximately 270 ° is curved.
  • the use of superconductors can be limited to those components of the beam guidance system which are provided specifically for the purpose of generating synchrotron radiation;
  • the synchrotron radiation source according to the invention contains at least one mirror magnet which has winding arrangements of superconducting strands and in which the web is curved by approximately 270 °, where it intersects itself at a cross point whose position is largely independent of the energy of the particle beam passing through the web (this property establishes the attribute "achromatic").
  • a synchrotron radiation source During the acceleration of a particle beam injected into the beam guidance system to a predetermined final energy, the electrical current passing through an achromatic mirror magnet need not be changed; When operating a synchrotron radiation source according to the invention, essentially all of the problems associated with the change in the magnetic excitation of a superconducting magnet can be avoided.
  • the large deflection angle of the mirror magnet of 270 ° results in a large angular range in which the synchrotron radiation generated is emitted; consequently, a synchrotron radiation source according to the invention can be used by many users simultaneously.
  • the rest of the beam guidance system of a synchrotron radiation source according to the invention can be constructed using conventional technology, deflection magnets (dipoles) and focusing magnets (quadrupoles) can be combined with one another in accordance with the relevant knowledge. It may be advantageous to choose the minimum radius of curvature of each deflecting magnet larger than the minimum radius of curvature of the mirror magnet; this reduces the generation of synchrotron radiation in the deflection magnets. This means a reduction in the requirements for the performance of the acceleration devices to be provided in the beam guiding system, which have to compensate for the energy loss in the circulating beams caused by the generation of the synchrotron radiation, and also lower requirements for the shielding of the deflecting magnets required for radiation protection reasons.
  • the magnetic field that can be generated in the mirror magnet is characterized by a field index that is between approximately 0.8 and approximately 1.5.
  • Magnetic field in a mirror magnet is along a first one Direction constant, and it is variable in a second direction perpendicular to the first direction such that it is proportional to a certain power of the depth of penetration, measured along the second direction from the entry point.
  • the field index is the exponent that designates this power - further explanations can be found in the article by HA Enge mentioned.
  • the properties of achromaticity can be achieved most favorably with a field index of the size mentioned; in particular, a completely afocal mirror magnet can be obtained with such a field index.
  • the mirror magnet with at least one beam tube for coupling out the synchrotron radiation.
  • the synchrotron radiation can be guided safely from the sy ⁇ chrotron radiation source to its destination.
  • Synchrotron radiation for use in X-ray lithography and the like is advantageously generated by a particle beam which is generated from electrons or positrons with kinetic energy of between approximately 400 MeV and approximately 2000 MeV.
  • the radius of curvature of a deflection magnet not specifically intended for generating synchrotron radiation in the context of a synchrotron radiation source for purposes of X-ray lithography or the like a value of approximately 1 m should be mentioned.
  • the synchrotron radiation generated in the deflection magnets can be kept at an intensity that is particularly harmless for reasons of radiation protection, so that simple
  • the use of ferro-magnetic yokes in the area of the curved particle path in the interior of the mirror magnet is omitted in the mirror magnet, and ferromagnetic components are used for shielding purposes at most.
  • Ferromagnetic components show significant saturation phenomena even in moderately high magnetic fields, so that the magnetic field strength in arrangements with such components must be limited to values of at most about 2 Tesla;
  • the design of a mirror magnet without ferromagnetic components enables particularly high fields, thus particularly small radii of curvature and particularly high yield of synchrotron radiation.
  • Figure 1 is a schematic representation of the synchrotron radiation source according to the invention.
  • Figure 1 shows schematically the overall design of the synchrotron radiation source according to the invention.
  • the path 1 along which the electrons or positrons to be accelerated and / or stored move is determined by the various components of the beam guidance system.
  • the beam guidance system includes, in particular, the mirror magnet 2, in which the particle path is deflected by 270 ° and guided in a loop, as well as deflection magnets 3, 4 and focusing magnets 5, 6.
  • the deflection magnets 3, 4 essentially produce magnetic dipole fields for the curvature of the path 1 ; they can be designed both as one-piece deflection magnets 3 and as combinations of a plurality of deflection magnets 4, it being possible, if appropriate, to combine special focusing magnets 5.
  • the selection of the deflection magnets 3, 4 is to be adapted to the respective requirements of the individual case; the number of deflection magnets 3, 4 to be provided, as well as the deflection angle of each deflection magnet, can be freely arranged. Furthermore, the beam guidance system has focusing magnets 5, 6 which are used to shape the cross section of the
  • paired focusing magnets 6 and / or focusing magnets 5 connected to deflection magnets 4 are used.
  • further components can be included in the beam guidance system, for example devices for position control of the particle beam in a plane perpendicular to the respective beam direction.
  • Devices for building up the particle beam for example a beam injector 13, and devices for accelerating the particles and for compensating for their energy loss caused by the generation of the synchrotron radiation 15, for example a high-frequency resonator 14, are customary 7 fed to the respective use.
  • FIG. 2 shows a winding arrangement 8 made of superconducting windings 10, as used to form a mirror magnet 2 could be used.
  • the illustration is merely to be regarded as a sketch; the specific design of the windings 10 is to be adapted to the requirements to be made of the mirror magnet 2 using customary methods.
  • Each winding 10 has a main section 11 which is arranged parallel to the plane containing the web 1, above the region of the mirror magnet 2 containing the web 1.
  • the main sections 11 are arranged at certain intervals from one another, so that the desired field is achieved in the plane of the web 1.
  • the windings 10 are closed by means of return sections 12, which are arranged in regions away from the web 1 in the mirror magnet.
  • shielding elements 16 are shown, which on the one hand shield the web 1 outside the mirror magnet 2 from its magnetic field and on the other hand keep the field generated by the return sections 12 away from the web 1.
  • FIG. 3 shows the spatial arrangement of two winding arrangements 8, 9 to form a mirror magnet.
  • the upper winding arrangement 8 and the lower winding arrangement 9 are arranged essentially congruently with a certain distance above one another, and the particles move approximately in the plane lying centrally between the upper winding arrangement 8 and the lower winding arrangement 9.
  • the shielding element 16 has an opening 17 through which a particle enters the magnetic field generated by the winding arrangements 8, 9.
  • the return sections 12 of the winding arrangements 8, 9 are each combined to form compact return rods; the mechanical requirements for superconducting magnet arrangements can thus be optimally taken into account.
  • the synchrotron radiation source is easy to handle and enables the generation of synchrotron radiation with long-term constant, particularly favorable parameters.

Abstract

L'invention concerne une source de rayonnement synchrotron comportant un système de guidage des faisceaux servant à accélérer et à stocker un faisceau d'électrons ou de positrons sur une orbite fermée (1), ce système de guidage des faisceaux comportant, pour la production du rayonnement synchrotron (15), au moins un aimant symétrique approximativement achromatique (2) qui est formé d'enroulements supraconducteurs (8, 9) et dans lequel l'orbite (1) est incurvée de 270° environ. D'autres éléments du système de guidage des faisceaux, comme des aimants de déflexion (3; 4) et des aiments de focalisation (5; 6), ne doivent pas nécessairement être constitués de composants supraconducteurs. La source de rayonnement synchrotron objet de l'invention permet d'utiliser tous les avantages des supraconducteurs en évitant au maximum les inconvénients qui s'y rattachent, étant donné que l'utilisation de composants supraconducteurs est limitée aux éléments spécialement destinés à produire le rayonnement synchrotron (15).
EP90911616A 1990-08-06 1990-08-06 Source de rayonnement synchrotron Withdrawn EP0542737A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
PCT/DE1990/000605 WO1992003028A1 (fr) 1990-08-06 1990-08-06 Source de rayonnement synchrotron
US08/014,401 US5341104A (en) 1990-08-06 1993-02-05 Synchrotron radiation source

Publications (1)

Publication Number Publication Date
EP0542737A1 true EP0542737A1 (fr) 1993-05-26

Family

ID=25956101

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90911616A Withdrawn EP0542737A1 (fr) 1990-08-06 1990-08-06 Source de rayonnement synchrotron

Country Status (4)

Country Link
US (1) US5341104A (fr)
EP (1) EP0542737A1 (fr)
JP (1) JPH06501334A (fr)
WO (1) WO1992003028A1 (fr)

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WO2006079429A1 (fr) 2005-01-26 2006-08-03 BSH Bosch und Siemens Hausgeräte GmbH Procede pour essorer des textiles apres un processus d'impregnation

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US5488046A (en) * 1993-11-03 1996-01-30 G. D. Searle & Co. Carbamic acid derivatives of substituted dibenzoxazepine compounds, pharmaceutical compositions and methods of use
EP1790203B1 (fr) 2004-07-21 2015-12-30 Mevion Medical Systems, Inc. Generateur de forme d'ondes a radiofrequence programmable pour un synchrocyclotron
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US8581523B2 (en) 2007-11-30 2013-11-12 Mevion Medical Systems, Inc. Interrupted particle source
US8933650B2 (en) 2007-11-30 2015-01-13 Mevion Medical Systems, Inc. Matching a resonant frequency of a resonant cavity to a frequency of an input voltage
US8749179B2 (en) * 2012-08-14 2014-06-10 Kla-Tencor Corporation Optical characterization systems employing compact synchrotron radiation sources
JP6523957B2 (ja) 2012-09-28 2019-06-05 メビオン・メディカル・システムズ・インコーポレーテッド 磁場を変更するための磁性シム
WO2014052721A1 (fr) 2012-09-28 2014-04-03 Mevion Medical Systems, Inc. Système de commande pour un accélérateur de particules
US9545528B2 (en) 2012-09-28 2017-01-17 Mevion Medical Systems, Inc. Controlling particle therapy
WO2014052718A2 (fr) 2012-09-28 2014-04-03 Mevion Medical Systems, Inc. Focalisation d'un faisceau de particules
TW201424467A (zh) 2012-09-28 2014-06-16 Mevion Medical Systems Inc 一粒子束之強度控制
TW201424466A (zh) 2012-09-28 2014-06-16 Mevion Medical Systems Inc 磁場再生器
EP2901820B1 (fr) 2012-09-28 2021-02-17 Mevion Medical Systems, Inc. Focalisation d'un faisceau de particules à l'aide d'une variation de champ magnétique
US10254739B2 (en) 2012-09-28 2019-04-09 Mevion Medical Systems, Inc. Coil positioning system
EP3581242B1 (fr) 2012-09-28 2022-04-06 Mevion Medical Systems, Inc. Réglage de l'énergie d'un faisceau de particules
US8791656B1 (en) 2013-05-31 2014-07-29 Mevion Medical Systems, Inc. Active return system
US9730308B2 (en) 2013-06-12 2017-08-08 Mevion Medical Systems, Inc. Particle accelerator that produces charged particles having variable energies
WO2015048468A1 (fr) 2013-09-27 2015-04-02 Mevion Medical Systems, Inc. Balayage par un faisceau de particules
US9962560B2 (en) 2013-12-20 2018-05-08 Mevion Medical Systems, Inc. Collimator and energy degrader
US10675487B2 (en) 2013-12-20 2020-06-09 Mevion Medical Systems, Inc. Energy degrader enabling high-speed energy switching
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Also Published As

Publication number Publication date
US5341104A (en) 1994-08-23
JPH06501334A (ja) 1994-02-10
WO1992003028A1 (fr) 1992-02-20

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