EP0127523B1 - Elektronzyklotronresonanz-Ionenquelle - Google Patents

Elektronzyklotronresonanz-Ionenquelle Download PDF

Info

Publication number
EP0127523B1
EP0127523B1 EP84401014A EP84401014A EP0127523B1 EP 0127523 B1 EP0127523 B1 EP 0127523B1 EP 84401014 A EP84401014 A EP 84401014A EP 84401014 A EP84401014 A EP 84401014A EP 0127523 B1 EP0127523 B1 EP 0127523B1
Authority
EP
European Patent Office
Prior art keywords
ion
magnetic field
coils
group
extraction system
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
EP84401014A
Other languages
English (en)
French (fr)
Other versions
EP0127523A1 (de
Inventor
Marc Delaunay
René Gualandris
Richard Geller
Claude Jaquot
Paul Ludwig
Jean-Marc Mathonnet
Jean-Claude Rocco
Pierre Sermet
Francois Zadworny
Francois Bourg
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.)
Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Original Assignee
Commissariat a lEnergie Atomique CEA
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 Commissariat a lEnergie Atomique CEA filed Critical Commissariat a lEnergie Atomique CEA
Publication of EP0127523A1 publication Critical patent/EP0127523A1/de
Application granted granted Critical
Publication of EP0127523B1 publication Critical patent/EP0127523B1/de
Expired legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J27/00—Ion beam tubes
    • H01J27/02—Ion sources; Ion guns
    • H01J27/16—Ion sources; Ion guns using high-frequency excitation, e.g. microwave excitation
    • H01J27/18—Ion sources; Ion guns using high-frequency excitation, e.g. microwave excitation with an applied axial magnetic field

Definitions

  • the present invention relates to a source of ions with cyclotron resonance of electrons. It finds many applications, depending on the different values of the range of kinetic energy of the extracted ions, in the fields of vaporization (sputtering) of thin layers, microgravure, ion implantation, heating by fast neutrons of the plasma of fusion reactors, tandem accelerators, synchrocyclotron, ... etc.
  • the ions are formed by strongly ionizing a gas or a vapor of a solid material, contained in a microwave cavity, thanks to the combined action of a high frequency electromagnetic field, established in the cavity, and a resulting magnetic field prevailing in said cavity.
  • FIG. 1 represents a diagram showing the curve of the magnetic field as a function of the distance along the central axis of the ion source seton the prior art in superposition with a schematic representation of the location of the main elements constituting this source .
  • the curve of the magnetic field 1 provided by the set of coils has two maxima at the locations of the first group 2 and the third group 4 of coils and a minimum between these two maxima at the location of the second group 3 of coils, the latter group being supplied in counter-field.
  • the maximum values are greater than the value B r of the magnetic induction corresponding to the cyclotronic resonance, this resonance being reached between the two maxima.
  • the plasma is therefore created and confined in the region of the ion source which lies between said maxima of the magnetic field.
  • the maximum and minimum values of the magnetic induction of this ion source taken for the example, are 0.42 and 0.32 T (4,200 and 3,200 Gauss) respectively.
  • the cyclotronic resonance of the electrons takes place at 0.36 T (3600 Gauss), the frequency of the injected high frequency wave being fixed at around 10 GHz.
  • the ions created in the plasma are finally extracted by an extraction system 5, made up of electrodes, which are located downstream of the second maximum of the magnetic field.
  • an extraction system 5 made up of electrodes, which are located downstream of the second maximum of the magnetic field.
  • the ions are therefore extracted in a magnetic field of the same order of magnitude as the field of cyclotron resonance.
  • the magnetic field must therefore be kept constant throughout the sliding space of the ion beam up to the point of its application or of the transformation of the ions in neutral particles.
  • the field to be kept constant corresponds to an induction of about 0.36 T (3,600 Gauss), the electrical energy consumed by the coils 6 creating this magnetic field is of the order of 1 Megawatt.
  • the extraction system When using low energy ions (less than 1 keV), the extraction system does not allow high densities to be extracted. To increase the latter, the ion beam can be compressed downstream of the ion source.
  • the magnetic field must be increased proportionally.
  • the present invention aims to remedy these drawbacks. For this, it provides for a modification of the magnetic configuration of confinement of the plasma in an ion source with cyclotron resonance of the electrons, which allows the extraction of the ions in a magnetic field clearly lower than that of the ion sources of the prior art.
  • the present invention specifically relates to a source of electrons with cyclotron resonance of electrons comprising a container containing a gas or a vapor of a material intended to form a plasma, the latter being created and confined in a magnetic field configuration, a microwave power injection system at one end of the container, this injection system comprising a sealed window, and an ion extraction system, characterized in that the configration of magnetic field is produced by two groups of coils, a first group, located in the plane defined by the watertight window of the microwave power injection system and surrounding it, providing the magnetic field confining the plasma, and a second group, supplied with counter field relative to the first group, surrounding the ion extraction system, the magnetic induction provided by all the groups of coils in the source axis having a maximum value, sup higher than that of the cyclotronic resonance, at the location of the first group of coils and decreasing to a minimum value at the location of the ion extraction system, passing through the value of the corresponding magnetic induction B r at
  • a third group of coils mounted downstream of the ion extraction system and supplied in the same direction as the first group, provides a magnetic field greater than that of the d system. extraction to compress the beam of extracted ions.
  • the position of the extraction system in the source is chosen such that the weak magnetic field at the location of the extraction is provided only by the first group of coils.
  • the magnetic configuration of the confinement of the plasma additionally comprises a multipolar magnetic configuration constituted by permanent magnets.
  • the magnetic field corresponding to the cyclotronic resonance is reached at a distance of the order of a few centimeters downstream of the junction between the microwave injector and the cavity of the ion source.
  • the gas is injected upstream of the ion extraction system and in its vicinity.
  • the ion extraction system consists of a single electrode.
  • the gas intended to form a plasma is deuterium and the minimum magnetic field at the location of the second group of coils is of the order of a few hundred Gauss.
  • a vacuum cavity 9 of cylindrical shape of revolution for example, one of the ends carries an injector 8 of microwave power and the other end is connected to the place of use of the ions.
  • the cavity 9 can have any shape depending on the character of the ion source.
  • the microwave power injection system 8 can be constituted by several microwave injectors. 17 is introduced a gas or a vapor for forming a plasma at a low pressure of which 0.13 Pa (10- 3 Torr) upstream of the ion extraction system and in its vicinity.
  • An axial static magnetic field is applied by means of coils which surround the cavity. It is also conceivable to use permanent magnets surrounding the cavity to provide the confining magnetic field.
  • the plasma is created at another location and then injected into the cavity 9.
  • the plasma is confined in the magnetic configuration obtained via two groups of coils 11, 12.
  • the first group of coils 11 is located in the plane defined by the sealed window 13 of the microwave injector 8 and surrounds it.
  • the second group of coils 12 is placed at a predetermined distance downstream from the first group of coils and is supplied in counter-field with respect to the first group.
  • the combination of these two groups of coils provides a magnetic field which has a maximum value at the location of the first group of coils 11. This value is chosen to be greater than the value B ,, corresponding to the cyclotron resonance of electrons.
  • the magnetic field decreases to a minimum value at the location of the second group of coils 12.
  • the magnetic field reaches the value of the magnetic field B r corresponding to the cyclotronic resonance.
  • the profile of the magnetic field is chosen such that the cyclotronic resonance of the electrons takes place a few centimeters downstream of the junction between the injector of the microwave power and the cavity.
  • the resonance zone is located far enough from the window 13 so that the plasma 10 created at this location hardly diffuses towards it and therefore does not risk damaging it.
  • the resonance is far enough from the walls of the cavity so that the plasma density is not reduced.
  • the number of coils forming a group depends on the magnetic field to be supplied.
  • a multipolar magnetic configuration is installed between the first 11 and the second 12 groups of coils.
  • Figure 3 shows schematically in cross section along section A-A of Figure 2a, a hexapolar configuration of the additional magnetic confinement.
  • the plasma 10 is confined by the lines of force of the magnetic field created by permanent magnets 18 distributed in a ring around the cylindrical part of the cavity which surrounds the plasma and whose polarities are alternated.
  • the frequency of the pulse of the microwave field being approximately 10 GHz
  • the maximum value of the induction B max at the location of the first group of coils is preferably chosen around 0.4 T (4,000 Gauss) and the value at the location of the second group of coils is preferably the order of 10 -2 T (hundreds of Gauss).
  • the ion extraction system 14 is installed inside the coils forming the second group.
  • this value of the magnetic induction at the location of the extraction system is less than 10% of the value of the induction B r corresponding to the cyclotronic resonance.
  • the extraction system can be produced in the form of a single electrode.
  • the ion current emitted by the ion source according to the invention is double compared to that of a conventional source.
  • the ion current increases.
  • the beam extracted from the ion source can be compressed, downstream of the extraction electrodes, by the application of a magnetic field greater than that applied to the extraction system 14.
  • the density of the ion current increases proportionally applied magnetic field.
  • the energy consumption of these coils is reduced by a factor greater than ten; there is therefore a significant energy saving.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Electron Sources, Ion Sources (AREA)
  • Particle Accelerators (AREA)

Claims (8)

1. Elektronzyklotronresonanz-lonenquelle (7) mit einem Behälter (9), der ein Gas oder Dampf eines Materials enthält, welches ein Plasma (10) bilden soll, wobei dieses in einer Magnetfeldkonfiguration erzeugt und begrenzt wird, einem Einspeisesystem (8) für eine Hyperfrequenzleistung an einem der Behälterenden, wobei dieses Einspeisesystem ein dichtes Fenster (13) und ein Extraktionssystem (14) für die Ionen umfaßt, dadurch gekennzeichnet, daß die Magnetfeldkonfiguration von zwei Gruppen von Spulen (11, 12) erzeugt wird, einer ersten Gruppe (11), die sich in der durch das dichte Fenster (13) des Einspeisesystems (8) für die Hyperfrequenzleistung festgelegten Ebene befindet und jenes umgibt und das das Plasma begrenzende Magnetfeld liefert, und einer zweiten Gruppe (12), die in bezug auf die erste Gruppe mit Gegenfeld gespeist wird und das Extraktionssystem (14) für die Ionen umgibt, wobei die von der Gesamtheit der Spulengruppen (11, 12) auf der Achse der lonenquelle gelieferte, magnetische Induktion an der Stelle der ersten Spulengruppe (11) einen größeren maximalen Wert als derjenige der Zyklotronresonanz aufweist und bis auf einen minimalen Wert an der Stelle des Extraktionssystems (14) für die Ionen abfällt, wobei sie zwischen den zwei Spulengruppen (11, 12) durch den Lert der magnetischen Induktion (Br) hindurchgeht, die der Zyklotronresonanz entspricht.
2. lonenquelle nach Anspruch 1, dadurch gekennzeichnet, daß eine dritte Spulengruppe (15) stromabwärts des Extraktionssystems (14) für die Ionen angebracht ist und mit dem gleichen Sinn wie die erste Gruppe gespeist wird und ein Magnetfeld liefert, welches größer als dasjenige des Extraktionssystems ist, um das Bündel (16) von extrahierten Ionen zusammenzudrücken.
3. lonenquelle nach Anspruch 1 oder 2, welches dahingehend abgeändert ist, daß die zweite Spulengruppe unterdrückt ist, wobei die Position des Extraktionssystems bei der Quelle dann so gewählt ist, daß das schwache Magnetfeld an der Extraktionsstelle nur von der ersten Spulengruppe geliefert wird.
4. Ionenquelle nach irgendeinem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß die magnetische Konfiguration zur Begrenzung des Plasmas zusätzlich eine mehrpolige Konfiguration umfaßt, die von Permanentmagneten (18) gebildet ist.
5. lonenquelle nach irgendeinem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß das der Zyklotronresonanz entsprechende Magnetfeld mit einem Abstand von der Grössenordnung von einigen Zentimetern stromabwärts der Verbindung des Hyperfrequenz-Einspeisesystems (8) mit dem Hohlraum (9) der lonenquelle erhalten wird.
6. lonenquelle nach irgendeinem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß das Einführen des Gases (17) stromaufwärts des Extraktionssystems für die Ionen und in dessen Nähe erfolgt.
7. lonenquelle nach irgendeinem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß das Extraktionssystem (14) für die lonen von einer einzigen Elektrode gebildet ist.
8. Ionenquelle nach irgendeinem der Ansprüche 1 bis 7, dadurch gekennzeichnet, daß das Gas, welches ein Plasma bilden soll, Deuterium ist und daß das Magnetfeld an der Stelle des Extraktionssystems (14) in der Größenordnung von einigen 10-2T ist.
EP84401014A 1983-05-20 1984-05-17 Elektronzyklotronresonanz-Ionenquelle Expired EP0127523B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8308401 1983-05-20
FR8308401A FR2546358B1 (fr) 1983-05-20 1983-05-20 Source d'ions a resonance cyclotronique des electrons

Publications (2)

Publication Number Publication Date
EP0127523A1 EP0127523A1 (de) 1984-12-05
EP0127523B1 true EP0127523B1 (de) 1988-08-10

Family

ID=9289043

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84401014A Expired EP0127523B1 (de) 1983-05-20 1984-05-17 Elektronzyklotronresonanz-Ionenquelle

Country Status (6)

Country Link
US (1) US4638216A (de)
EP (1) EP0127523B1 (de)
JP (1) JPS6041735A (de)
CA (1) CA1232375A (de)
DE (1) DE3473377D1 (de)
FR (1) FR2546358B1 (de)

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2572847B1 (fr) * 1984-11-06 1986-12-26 Commissariat Energie Atomique Procede et dispositif d'allumage d'une source d'ions hyperfrequence
FR2580427B1 (fr) * 1985-04-11 1987-05-15 Commissariat Energie Atomique Source d'ions negatifs a resonance cyclotronique des electrons
US4778561A (en) * 1987-10-30 1988-10-18 Veeco Instruments, Inc. Electron cyclotron resonance plasma source
DE3834984A1 (de) * 1988-10-14 1990-04-19 Leybold Ag Einrichtung zur erzeugung von elektrisch geladenen und/oder ungeladenen teilchen
DE3903322A1 (de) * 1989-02-04 1990-08-16 Nmi Naturwissenschaftl U Mediz Verfahren zur erzeugung von ionen
JPH0618108B2 (ja) * 1989-12-07 1994-03-09 雄一 坂本 電子サイクロトロン型イオン源
GB9009319D0 (en) * 1990-04-25 1990-06-20 Secr Defence Gaseous radical source
US5208512A (en) * 1990-10-16 1993-05-04 International Business Machines Corporation Scanned electron cyclotron resonance plasma source
ES2078735T3 (es) * 1991-05-21 1995-12-16 Materials Research Corp Modulo de grabado suave mediante util de agrupacion y generador de plasma ecr para el mismo.
DE4200235C1 (de) * 1992-01-08 1993-05-06 Hoffmeister, Helmut, Dr., 4400 Muenster, De
US6441569B1 (en) 1998-12-09 2002-08-27 Edward F. Janzow Particle accelerator for inducing contained particle collisions
FR2795906B1 (fr) * 1999-07-01 2001-08-17 Commissariat Energie Atomique Procede et dispositif de depot par plasma a la resonance cyclotron electronique de couches de tissus de nonofibres de carbone et couches de tissus ainsi obtenus
DE19933762C2 (de) * 1999-07-19 2002-10-17 Juergen Andrae Gepulste magnetische Öffnung von Elektronen-Zyklotron-Resonanz-Jonenquellen zur Erzeugung kurzer, stromstarker Pulse hoch geladener Ionen oder von Elektronen
FR2815954B1 (fr) * 2000-10-27 2003-02-21 Commissariat Energie Atomique Procede et dispositif de depot par plasma a la resonance cyclotron electronique de nanotubes de carbone monoparois et nanotubes ainsi obtenus
WO2002037521A2 (en) * 2000-11-03 2002-05-10 Tokyo Electron Limited Hall effect ion source at high current density
DE10058326C1 (de) * 2000-11-24 2002-06-13 Astrium Gmbh Induktiv gekoppelte Hochfrequenz-Elektronenquelle mit reduziertem Leistungsbedarf durch elektrostatischen Einschluss von Elektronen
US6876154B2 (en) * 2002-04-24 2005-04-05 Trikon Holdings Limited Plasma processing apparatus
US6812647B2 (en) * 2003-04-03 2004-11-02 Wayne D. Cornelius Plasma generator useful for ion beam generation
US7742167B2 (en) * 2005-06-17 2010-06-22 Perkinelmer Health Sciences, Inc. Optical emission device with boost device
US8006939B2 (en) 2006-11-22 2011-08-30 Lockheed Martin Corporation Over-wing traveling-wave axial flow plasma accelerator
US7870720B2 (en) * 2006-11-29 2011-01-18 Lockheed Martin Corporation Inlet electromagnetic flow control
WO2010132068A1 (en) 2009-05-15 2010-11-18 Alpha Source Llc Ecr particle beam source apparatus, system and method

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1020224A (en) * 1962-01-22 1966-02-16 Hitachi Ltd Improvements relating to an electron cyclotron resonance ultra-violet lamp
US3418206A (en) * 1963-04-29 1968-12-24 Boeing Co Particle accelerator
FR2147497A5 (de) * 1971-07-29 1973-03-09 Commissariat Energie Atomique
US4045677A (en) * 1976-06-11 1977-08-30 Cornell Research Foundation, Inc. Intense ion beam generator
US4393333A (en) * 1979-12-10 1983-07-12 Hitachi, Ltd. Microwave plasma ion source
FR2475798A1 (fr) * 1980-02-13 1981-08-14 Commissariat Energie Atomique Procede et dispositif de production d'ions lourds fortement charges et une application mettant en oeuvre le procede
JPS5947421B2 (ja) * 1980-03-24 1984-11-19 株式会社日立製作所 マイクロ波イオン源
JPS5779621A (en) * 1980-11-05 1982-05-18 Mitsubishi Electric Corp Plasma processing device

Also Published As

Publication number Publication date
FR2546358B1 (fr) 1985-07-05
JPS6041735A (ja) 1985-03-05
DE3473377D1 (en) 1988-09-15
FR2546358A1 (fr) 1984-11-23
JPH046060B2 (de) 1992-02-04
CA1232375A (en) 1988-02-02
EP0127523A1 (de) 1984-12-05
US4638216A (en) 1987-01-20

Similar Documents

Publication Publication Date Title
EP0127523B1 (de) Elektronzyklotronresonanz-Ionenquelle
EP0209469B1 (de) Verfahren und Apparat zur Mikrowellenanregung eines Plasmas bei der Elektronen-Zyklotronen-Resonanz
EP2798209B1 (de) Plasmatriebwerk und verfahren zur erzeugung eines plasmaantriebsschubs
EP2353347B1 (de) Einrichtung und verfahren zum erzeugen und/oder eingrenzen eines plasmas
EP0184475B1 (de) Verfahren und Vorrichtung zum Starten einer Mikrowellenionenquelle
FR2671931A1 (fr) Dispositif de repartition d'une energie micro-onde pour l'excitation d'un plasma.
FR2595868A1 (fr) Source d'ions a resonance cyclotronique electronique a injection coaxiale d'ondes electromagnetiques
EP2044816B1 (de) Vorrichtung und verfahren zum produzieren und/oder eingrenzen eines plasmas
EP0685143B1 (de) Lineare mikrowellenquelle zur plasmabehandlung von flächen.
EP0702843B1 (de) Hochenergie-ionimplantierungsvorrichtung vom schwach -oder mittelstromtyp und verwendung einer solchen vorrichtung
EP0199625B1 (de) Elektronzyklotronresonanzquelle negativer Ionen
EP2652766B1 (de) Elektron-zyklotron-resonanzionenquelle
EP0527082B1 (de) Elektroncyclotionresonanz-Ionenquelle vom Wellenleiter-Typ zur Erzeugung mehrfachgeladenen Ionen
EP0532411B1 (de) Elektronzyklotronresonanz-Ionenquelle mit koaxialer Zuführung elektromagnetischer Wellen
FR2969372A1 (fr) Dispositif d’ionisation a la resonance cyclotron electronique
EP0232651B1 (de) Elektronen-Zyklotron-Resonanz-Ionenquelle
EP0483004B1 (de) Quelle starkgeladener Ionen mit polarisierbarer Probe und mit Elektronzyklotronresonanz
EP2311061B1 (de) Elektronenzyklotronresonanzionengenerator
EP0813223B1 (de) Magnetfelderzeugungsvorrichtung und ECR Ionenquelle dafür
EP0514255B1 (de) Elektronzyklotronresonanz-Ionenquelle
FR2757310A1 (fr) Systeme magnetique, en particulier pour les sources ecr, permettant la creation de surfaces fermees d'equimodule b de forme et de dimensions quelconques

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): BE DE GB NL SE

17P Request for examination filed

Effective date: 19850508

17Q First examination report despatched

Effective date: 19861217

D17Q First examination report despatched (deleted)
RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: COMMISSARIAT A L'ENERGIE ATOMIQUE

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): BE DE GB NL SE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19880810

REF Corresponds to:

Ref document number: 3473377

Country of ref document: DE

Date of ref document: 19880915

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)
NLV1 Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act
NLXE Nl: other communications concerning ep-patents (part 3 heading xe)

Free format text: A REQUEST FOR RESTORATION TO THE PRIOR STATE HAS BEEN FILED ON 890205

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19940428

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19940429

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 19940503

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19940524

Year of fee payment: 11

EAL Se: european patent in force in sweden

Ref document number: 84401014.0

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19950517

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19950518

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Effective date: 19950531

BERE Be: lapsed

Owner name: COMMISSARIAT A L'ENERGIE ATOMIQUE

Effective date: 19950531

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19950517

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19960201

EUG Se: european patent has lapsed

Ref document number: 84401014.0