EP0712146B1 - Field effect electron source and method for producing same application in display devices working by cathodoluminescence - Google Patents

Field effect electron source and method for producing same application in display devices working by cathodoluminescence Download PDF

Info

Publication number
EP0712146B1
EP0712146B1 EP95402450A EP95402450A EP0712146B1 EP 0712146 B1 EP0712146 B1 EP 0712146B1 EP 95402450 A EP95402450 A EP 95402450A EP 95402450 A EP95402450 A EP 95402450A EP 0712146 B1 EP0712146 B1 EP 0712146B1
Authority
EP
European Patent Office
Prior art keywords
diamond
electrically insulating
source
carbon
holes
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 - Lifetime
Application number
EP95402450A
Other languages
German (de)
French (fr)
Other versions
EP0712146A1 (en
Inventor
Joel Danroc
Danh Van Tran
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 EP0712146A1 publication Critical patent/EP0712146A1/en
Application granted granted Critical
Publication of EP0712146B1 publication Critical patent/EP0712146B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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
    • H01J9/022—Manufacture of electrodes or electrode systems of cold cathodes
    • H01J9/025—Manufacture of electrodes or electrode systems of cold cathodes of field emission cathodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J3/00—Details of electron-optical or ion-optical arrangements or of ion traps common to two or more basic types of discharge tubes or lamps
    • H01J3/02—Electron guns
    • H01J3/021—Electron guns using a field emission, photo emission, or secondary emission electron source
    • H01J3/022—Electron guns using a field emission, photo emission, or secondary emission electron source with microengineered cathode, e.g. Spindt-type
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2201/00—Electrodes common to discharge tubes
    • H01J2201/30—Cold cathodes
    • H01J2201/304—Field emission cathodes
    • H01J2201/30403—Field emission cathodes characterised by the emitter shape
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2201/00—Electrodes common to discharge tubes
    • H01J2201/30—Cold cathodes
    • H01J2201/304—Field emission cathodes
    • H01J2201/30446—Field emission cathodes characterised by the emitter material
    • H01J2201/30453—Carbon types
    • H01J2201/30457—Diamond
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2329/00—Electron emission display panels, e.g. field emission display panels

Definitions

  • the present invention relates to a source of field effect electrons.
  • the invention has the same fields of application than electron sources with microtips ("microtips").
  • the present invention applies to the field of display devices dishes also called “flat screens”, as well as manufacture of pressure measurement gauges.
  • a source of microtip electrons includes at least one cathode conductor on a substrate electrically insulating, an electrically insulating layer which covers this cathode conductor and at least one grid formed on this electrically insulating layer.
  • Holes are formed through the grid and the insulating layer above the cathode conductor.
  • micro-tips are formed in these holes and carried by the cathode conductor.
  • each micro-tip is substantially in the plane of the grid, this grid used to extract electrons from micro-tips.
  • the holes have very small dimensions (they have a diameter less than 2 ⁇ m).
  • These other known display devices include a cathodoluminescent anode placed opposite of an electron source comprising carbon layers diamond or diamond-like intended to emit electrons.
  • Diamond or diamond carbon emits electrons much more easily than materials conventionally used for the manufacture of micro-tips.
  • the minimum electric field from which one can obtain an electron emission can be twenty times lower that the minimum electric field corresponding to metals such as molybdenum.
  • the deposits obtained are continuous layers and not micro-tips.
  • the object of the present invention is to remedy to the previous drawbacks.
  • micro-cluster is meant a micro-heap composed of diamond or type carbon powder grains diamonds who are in direct contact with their closest neighbors and / or linked together by a metal.
  • the source object of the present invention emits more of electrons than a microtip source, due to the use, in the present invention, of particles carbon diamond or diamond type that have power higher emissivity than electron emitting materials conventional such as molybdenum.
  • this device has a more greater brightness than a micro-tip device, for same control voltage.
  • this device using a source according to the invention requires a voltage of order less than that required for a micro-tip device.
  • the micro-clusters can be made of diamond carbon particles or diamond type where such particles can be made dispersed in a metal.
  • the micro-clusters can be linked by a deposit of a metal intended to consolidate these micro-clusters, the particles of diamond or diamond-like carbon emerging from this deposit at the surface of micro-clusters.
  • the process which is the subject of the invention can be implemented used with large surface substrates and allows thus obtaining electron sources (and therefore screens large area (several dozen inches diagonally).
  • the temperature at which we form micro-clusters is close to room temperature (around 20 ° C).
  • baths that are necessary for the implementation of the process which is the subject of the invention have a long service life (several months).
  • the micro-clusters formed by electrophoresis are then linked using a metal by electrochemical deposition, in order to consolidate these micro-clusters.
  • the carbon particles diamond or diamond type have a size of around 1 ⁇ m or less than 1 ⁇ m.
  • These particles can be obtained at from natural or artificial diamond or by a method chosen from laser synthesis, deposition chemical vapor phase and physical phase deposition steam.
  • the holes formed through the grid layer and the electrically insulating layer can have a circular or rectangular shape.
  • the size of these holes can be chosen in an interval of approximately 1 ⁇ m to several tens of micrometers.
  • micro-clusters are formed according to the process object of the invention is comparable to the structure in which the micro-tips to make a micro-tip source.
  • the size of the holes that we form in the structure to implement the process subject of the invention may be significantly greater than that which is necessary for the implementation of a process manufacturing a micro-tip source.
  • Holes 10 are formed through these grids 8 and the insulating layer 6 above the cathode conductors 4.
  • Micro-clusters 12 containing particles carbon diamond or diamond type, are formed in the holes 10 and carried by the cathode conductors 4.
  • cathode conductors 4 are parallel and the grids 8 are parallel to each other and perpendicular to the conductors cathodic 4.
  • the holes 10 and therefore the micro-clusters 12 are found in the areas where these grids cross the cathode conductors.
  • micro-clusters in such an area that emit electrons when an electrical voltage appropriate is applied, by means not shown, between the cathode conductor 4 and the grid 8 which correspond to this zone.
  • a display device by cathodoluminescence is schematically represented in section in Figure 2.
  • This device includes the source of electrons 14 in Figure 1.
  • the device of Figure 2 also includes a cathodoluminescent anode 16 placed opposite the source 14 and separated from it by a space 18 in which we made the vacuum.
  • the cathodoluminescent anode 16 comprises a electrically insulating and transparent substrate 20 which is provided with an electrically conductive layer and transparent 22 forming an anode.
  • this layer 24 emits a light that a user of the device visualization observed through the transparent substrate 20.
  • the diameter D1 of holes (substantially circular) formed in the grid 8 and in the electrically insulating layer 6 can be advantageously greater than the diameter of the holes than contain micro-point electron sources described in documents (1) to (4).
  • this diameter D1 can take values on the order of 1 ⁇ m up to 20 ⁇ m.
  • Figure 4 schematically illustrates the makes the holes 10, instead of having a shape circular, may have a rectangular shape.
  • the width D2 of these holes 10 in the figure 4, rectangular, can be taken equal to diameter D1 mentioned above and can therefore be also significantly larger than the diameter of the holes micro-tip sources.
  • micro-clusters 12 we use diamond or diamond-like carbon powder.
  • This powder can be obtained by deposit chemical vapor phase, from a mixture hydrogen and light hydrocarbons.
  • This chemical vapor deposition can be assisted by an electron beam or be assisted by a plasma generated by microwaves.
  • the powder can also be synthesized by physical vapor deposition ("physical vapor” deposition "), from carbon targets (graphite for example) and a plasma gas such as argon alone or mixed with hydrogen, hydrocarbons without dopant or with a dopant like for example the diborane.
  • physical vapor deposition from carbon targets (graphite for example) and a plasma gas such as argon alone or mixed with hydrogen, hydrocarbons without dopant or with a dopant like for example the diborane.
  • This powder can also be obtained by laser ablation.
  • diamonds can be prepared carbon compression, high pressure and high temperature, then make the powder from of these artificial diamonds.
  • these carbon powders diamond and these diamond-like carbon powders are chosen so as to have a micronic particle size or submicron, preferably nanometric.
  • these carbon powders diamond or diamond type can be doped or not doped.
  • the deposition of the powder (particles of diamond or diamond type) leading to the formation of micro-clusters 12 in holes 10, on the cathode conductors 4, can be realized by electrophoresis (cataphoresis or anaphoresis), possibly supplemented by a metallic deposit electrochemical consolidation, or by co-deposit electrochemical of metal and carbon diamond or diamond type.
  • the structure provided with holes 10 is placed in a appropriate solution 26 and the bottom of each hole 10 is brought to positive potential during this phase of deposit.
  • drivers cathodics 4 are brought to this positive potential thanks to a suitable voltage source 28 whose terminal positive is connected to these cathode conductors 4 while the negative terminal of this source is connected to a platinum or steel counter electrode 32 stainless steel located in the bath at a distance from substrate about 1 to 5 cm.
  • the fine powder of carbon particles diamond or diamond type is suspended in solution 26 (before placing the structure in this solution).
  • the voltage supplied by the source 28 can go up to around 200 V.
  • this is the source 28 negative terminal which is connected to cathode conductors 4 while the positive terminal of the source 28 is connected to a counter-electrode 32 in platinum or stainless steel located in the bath a distance from the substrate of about 1 to 5 cm.
  • electrochemical deposition of a metal by example chosen from Ni, Co, Ag, Au, Rh or Pt or, more generally, among transition metals, alloys thereof and precious metals.
  • This electrode 33 is for example in nickel and solution 30 contains for example 300 g / l nickel sulfate, 30 g / l nickel chloride, 30 g / l of boric acid and 0.6 g / l of lauryl sulfate sodium.
  • an electric current of 4 A / dm 2 is used .
  • micro-clusters by electrochemical co-deposit of metal and carbon diamond or diamond type.
  • An appropriate current source is used, for example of the order of 4 A / dm 2 , and the negative terminal of this source is applied to the cathode conductors and the positive terminal of this source to a nickel electrode placed in the bath.
  • Nickel is deposited in the holes in bringing with it the diamond particles, hence the formation of nickel and diamond micro-clusters in these holes.
  • the tops of the micro-clusters are found substantially in the plane of the grids and these micro-clusters are not in contact with these grids.

Description

DOMAINE TECHNIQUETECHNICAL AREA

La présente invention concerne une source d'électrons à effet de champ.The present invention relates to a source of field effect electrons.

L'invention a les mêmes domaines d'application que les sources d'électrons à micro-pointes ("microtips").The invention has the same fields of application than electron sources with microtips ("microtips").

En particulier, la présente invention s'applique au domaine des dispositifs de visualisation plats encore appelés "écrans plats", ainsi qu'à la fabrication de jauges de mesure de pression.In particular, the present invention applies to the field of display devices dishes also called "flat screens", as well as manufacture of pressure measurement gauges.

ETAT DE LA TECHNIQUE ANTERIEURESTATE OF THE PRIOR ART

On connaít déjà des sources d'électrons à effet de champ.We already know sources of electrons field effect.

Ce sont les sources d'électrons à micro-pointes mentionnées plus haut.These are the sources of microtip electrons mentioned above.

Une source d'électrons à micro-pointes comprend au moins un conducteur cathodique sur un substrat électriquement isolant, une couche électriquement isolante qui recouvre ce conducteur cathodique et au moins une grille formée sur cette couche électriquement isolante.A source of microtip electrons includes at least one cathode conductor on a substrate electrically insulating, an electrically insulating layer which covers this cathode conductor and at least one grid formed on this electrically insulating layer.

Des trous sont formés à travers la grille et la couche isolante au-dessus du conducteur cathodique.Holes are formed through the grid and the insulating layer above the cathode conductor.

Les micro-pointes sont formées dans ces trous et portées par le conducteur cathodique.The micro-tips are formed in these holes and carried by the cathode conductor.

Le sommet de chaque micro-pointe se trouve sensiblement dans le plan de la grille, cette grille servant à extraire des électrons des micro-pointes. The top of each micro-tip is substantially in the plane of the grid, this grid used to extract electrons from micro-tips.

Les trous ont de très petites dimensions (ils ont un diamètre inférieur à 2 µm).The holes have very small dimensions (they have a diameter less than 2 µm).

Pour réaliser un dispositif de visualisation utilisant une telle source d'électrons à micro-pointes, on réalise un système de type "triode".To make a display device using such a microtip electron source, realizes a "triode" type system.

Plus précisément, on dispose, en face de la source, une anode cathodoluminescente.More specifically, we have, opposite the source, a cathodoluminescent anode.

Les électrons issus de la source viennent bombarder cette anode cathodoluminescente.The electrons from the source come bomb this cathodoluminescent anode.

On connaít également d'autres dispositifs de visualisation ayant une structure de type "diode".We also know other devices display with a "diode" type structure.

Ces autres dispositifs de visualisation connus comprennent une anode cathodoluminescente placée en regard d'une source d'électrons comprenant des couches de carbone diamant ou de type diamant destinées à émettre des électrons.These other known display devices include a cathodoluminescent anode placed opposite of an electron source comprising carbon layers diamond or diamond-like intended to emit electrons.

Ces couches sont obtenues par ablation laser ou par dépôt chimique en phase vapeur ("chemical vapour deposition").These layers are obtained by laser ablation or by chemical vapor deposition ("chemical vapor deposition").

Le carbone diamant ou de type diamant émet beaucoup plus facilement des électrons que les matériaux classiquement utilisés pour la fabrication des micro-pointes.Diamond or diamond carbon emits electrons much more easily than materials conventionally used for the manufacture of micro-tips.

Avec le carbone diamant ou de type diamant, le champ électrique minimal à partir duquel on peut obtenir une émission d'électrons peut être vingt fois plus faible que le champ électrique minimal correspondant à des métaux comme par exemple le molybdène.With diamond or diamond-like carbon, the minimum electric field from which one can obtain an electron emission can be twenty times lower that the minimum electric field corresponding to metals such as molybdenum.

Malheureusement, le dépôt des couches de carbone diamant ou de type diamant, avec les méthodes mentionnées plus haut, a lieu à haute température (de l'ordre de 700°C).Unfortunately, the deposition of the layers of carbon diamond or diamond type, with methods mentioned above, takes place at high temperature (from around 700 ° C).

De plus, il est impossible d'obtenir directement des micro-pointes par ces méthodes. In addition, it is impossible to obtain directly from micro-tips by these methods.

Les dépôts obtenus sont des couches continues et non pas des micro-pointes.The deposits obtained are continuous layers and not micro-tips.

Les dispositifs de visualisation qui en résultent sont, comme on l'a vu plus haut, de type "diode", ce qui pose un problème en ce qui concerne leur adressage.The display devices which result are, as we saw above, of type "diode", which poses a problem regarding their addressing.

Il faut en effet réaliser des systèmes électroniques d'adressage permettant d'appliquer des tensions de l'ordre de plusieurs centaines de volts à ces dispositifs.It is indeed necessary to realize systems addressing electronics for applying voltages on the order of several hundred volts at these devices.

De plus, la température élevée à laquelle sont formées les couches de carbone diamant ou de type diamant interdit l'utilisation de verre standard en tant que substrat destiné à porter ces couches.In addition, the high temperature at which are formed the diamond or diamond carbon layers prohibits the use of standard glass as substrate intended to carry these layers.

EXPOSE DE L'INVENTIONSTATEMENT OF THE INVENTION

La présente invention a pour but de remédier aux inconvénients précédents.The object of the present invention is to remedy to the previous drawbacks.

Elle a pour objet une source d'électrons à effet de champ, cette source comprenant :

  • sur un substrat électriquement isolant, au moins une première électrode jouant le rôle de conducteur cathodique,
  • une couche électriquement isolante qui recouvre ce conducteur cathodique,
  • au moins une deuxième électrode jouant le rôle de grille, formée sur la couche électriquement isolante, des trous étant formés à travers cette grille et la couche électriquement isolante au-dessus du conducteur cathodique, et
  • des éléments qui sont susceptibles d'émettre des électrons et qui sont formés dans ces trous et portés par le conducteur cathodique,
cette source étant caractérisée en ce que ces éléments sont des micro-amas contenant des particules de carbone diamant ou de type diamant ("diamond like carbon" ou DLC dans les articles en langue anglaise).Its subject is a source of field effect electrons, this source comprising:
  • on an electrically insulating substrate, at least a first electrode playing the role of cathode conductor,
  • an electrically insulating layer which covers this cathode conductor,
  • at least one second electrode acting as a grid, formed on the electrically insulating layer, holes being formed through this grid and the electrically insulating layer above the cathode conductor, and
  • elements which are capable of emitting electrons and which are formed in these holes and carried by the cathode conductor,
this source being characterized in that these elements are micro-clusters containing particles of diamond carbon or of the diamond type ("diamond like carbon" or DLC in articles in English).

Par "micro-amas", on entend un micro-tas composé de grains de poudre de carbone diamant ou de type diamant qui sont en contact direct avec leurs plus proches voisins et/ou liés entre eux par un métal.By "micro-cluster" is meant a micro-heap composed of diamond or type carbon powder grains diamonds who are in direct contact with their closest neighbors and / or linked together by a metal.

Pour une même tension électrique de commande, la source objet de la présente invention émet plus d'électrons qu'une source à micro-pointes, du fait de l'utilisation, dans la présente invention, des particules de carbone diamant ou de type diamant qui ont un pouvoir émissif plus élevé que des matériaux émetteurs d'électrons classiques comme par exemple le molybdène.For the same electrical control voltage, the source object of the present invention emits more of electrons than a microtip source, due to the use, in the present invention, of particles carbon diamond or diamond type that have power higher emissivity than electron emitting materials conventional such as molybdenum.

Ainsi, dans le cas de l'utilisation d'une source conforme à l'invention pour fabriquer par exemple un dispositif de visualisation, ce dispositif a une plus grande luminosité qu'un dispositif à micro-pointes, pour même tension de commande.So in the case of using a source according to the invention for manufacturing for example a viewing device, this device has a more greater brightness than a micro-tip device, for same control voltage.

A luminosités égales, ce dispositif utilisant une source conforme à l'invention nécessite une tension de commande inférieure à celle qui est nécessaire à un dispositif à micro-pointes.At equal luminosities, this device using a source according to the invention requires a voltage of order less than that required for a micro-tip device.

De plus, l'utilisation d'une source conforme à l'invention conduit à un système de type "triode" qui nécessite des tensions de commande inférieures à celles qui sont nécessaires aux dispositifs de type "diode" mentionnés plus haut, qui utilisent des couches de carbone diamant ou de type diamant.In addition, the use of a source conforming to the invention leads to a "triode" type system which requires lower control voltages than which are necessary for "diode" type devices mentioned above, which use carbon layers diamond or diamond type.

Dans la présente invention, les micro-amas peuvent être faits de particules de carbone diamant ou de type diamant ou peuvent être faits de telles particules dispersées dans un métal. In the present invention, the micro-clusters can be made of diamond carbon particles or diamond type where such particles can be made dispersed in a metal.

Dans la source objet de l'invention, les micro-amas peuvent être liés par un dépôt d'un métal destiné à consolider ces micro-amas, les particules de carbone diamant ou de type diamant émergeant de ce dépôt à la surface des micro-amas.In the source object of the invention, the micro-clusters can be linked by a deposit of a metal intended to consolidate these micro-clusters, the particles of diamond or diamond-like carbon emerging from this deposit at the surface of micro-clusters.

La présente invention concerne également un dispositif de visualisation par cathodoluminescence comprenant :

  • une source d'électrons à effet de champ, et
  • une anode cathodoluminescente comprenant une couche d'un matériau cathodoluminescent,
dispositif caractérisé en ce que la source est celle qui fait l'objet de l'invention.The present invention also relates to a cathodoluminescence display device comprising:
  • a source of field effect electrons, and
  • a cathodoluminescent anode comprising a layer of a cathodoluminescent material,
device characterized in that the source is that which is the subject of the invention.

On a vu plus haut les avantages d'un tel dispositif par rapport aux dispositifs connus utilisant des micro-pointes et aux dispositifs comprenant des couches de carbone diamant ou de type diamant.We saw above the advantages of such a device compared to known devices using micro-tips and devices comprising layers of diamond carbon or diamond type.

La présente invention concerne aussi un procédé de fabrication d'une source d'électrons à effet de champ, procédé selon lequel :

  • on fabrique une structure comprenant un substrat électriquement isolant, au moins un conducteur cathodique sur ce substrat, une couche électriquement isolante qui recouvre chaque conducteur cathodique et une couche de grille électriquement conductrice qui recouvre cette couche électriquement isolante,
  • on forme des trous à travers la couche de grille et la couche électriquement isolante, au niveau de chaque conducteur cathodique, et
  • on forme, dans chaque trou, un élément susceptible d'émettre des électrons,
ce procédé étant caractérisé en ce que les éléments sont des micro-amas qui contiennent des particules de carbone diamant ou de type diamant et sont formés par électrophorèse ou par co-dépôt électrochimique de métal et de carbone diamant ou de type diamant.The present invention also relates to a method for manufacturing a field effect electron source, method according to which:
  • a structure is made up comprising an electrically insulating substrate, at least one cathode conductor on this substrate, an electrically insulating layer which covers each cathode conductor and an electrically conductive grid layer which covers this electrically insulating layer,
  • holes are formed through the grid layer and the electrically insulating layer, at the level of each cathode conductor, and
  • an element capable of emitting electrons is formed in each hole,
this process being characterized in that the elements are micro-clusters which contain diamond or diamond-like carbon particles and are formed by electrophoresis or by electrochemical co-deposition of metal and diamond or diamond-like carbon.

Le procédé objet de l'invention peut être mis en oeuvre avec des substrats de grande surface et permet ainsi l'obtention de sources d'électrons (et donc d'écrans de visualisation) de grande surface (plusieurs dizaines de pouces de diagonale).The process which is the subject of the invention can be implemented used with large surface substrates and allows thus obtaining electron sources (and therefore screens large area (several dozen inches diagonally).

De plus, dans le procédé objet de l'invention, la température à laquelle on forme les micro-amas est voisine de la température ambiante (de l'ordre de 20°C).In addition, in the process which is the subject of the invention, the temperature at which we form micro-clusters is close to room temperature (around 20 ° C).

Il est ainsi possible d'utiliser, pour fabriquer une source conforme à l'invention, un substrat en verre ordinaire (sodocalcique), sans précautions particulières.It is thus possible to use, for manufacture a source according to the invention, a substrate in ordinary glass (soda-lime), without precautions particular.

On notera aussi que le procédé objet de l'invention est plus simple que le procédé de fabrication des sources à micro-pointes car, contrairement à ce dernier, il n'utilise ni couche sacrificielle ("lift off layer") ni dépôt sous vide.It will also be noted that the process which is the subject of the invention is simpler than the manufacturing process sources with micro-points because, contrary to what last, it uses neither sacrificial layer ("lift off layer ") or vacuum deposition.

En outre, les bains qui sont nécessaires pour la mise en oeuvre du procédé objet de l'invention ont une durée de vie importante (plusieurs mois).In addition, the baths that are necessary for the implementation of the process which is the subject of the invention have a long service life (several months).

Selon un mode de mise en oeuvre particulier du procédé objet de l'invention, les micro-amas formés par électrophorèse sont ensuite liés à l'aide d'un métal par dépôt électrochimique, afin de consolider ces micro-amas.According to a particular mode of implementation of the process which is the subject of the invention, the micro-clusters formed by electrophoresis are then linked using a metal by electrochemical deposition, in order to consolidate these micro-clusters.

De préférence, les particules de carbone diamant ou de type diamant ont une taille de l'ordre de 1 µm ou de moins de 1 µm.Preferably, the carbon particles diamond or diamond type have a size of around 1 µm or less than 1 µm.

Préférentiellement on utilise des poudres nanométriques.Preferably we use powders nanometric.

Ces particules peuvent être obtenues à partir de diamant naturel ou artificiel ou par une méthode choisie parmi la synthèse par laser, le dépôt chimique en phase vapeur et le dépôt physique en phase vapeur.These particles can be obtained at from natural or artificial diamond or by a method chosen from laser synthesis, deposition chemical vapor phase and physical phase deposition steam.

Les trous formés à travers la couche de grille et la couche électriquement isolante peuvent avoir une forme circulaire ou rectangulaire.The holes formed through the grid layer and the electrically insulating layer can have a circular or rectangular shape.

La taille de ces trous peut être choisie dans un intervalle allant d'environ 1 µm jusqu'à plusieurs dizaines de micromètres.The size of these holes can be chosen in an interval of approximately 1 µm to several tens of micrometers.

La structure dans laquelle on forme les micro-amas conformément au procédé objet de l'invention est comparable à la structure dans laquelle on forme les micro-pointes pour fabriquer une source à micro-pointes.The structure in which micro-clusters are formed according to the process object of the invention is comparable to the structure in which the micro-tips to make a micro-tip source.

En revanche, la taille des trous que l'on forme dans la structure pour mettre en oeuvre le procédé objet de l'invention peut être nettement supérieure à celle qui est nécessaire à la mise en oeuvre d'un procédé de fabrication d'une source à micro-pointes.On the other hand, the size of the holes that we form in the structure to implement the process subject of the invention may be significantly greater than that which is necessary for the implementation of a process manufacturing a micro-tip source.

Ceci est très avantageux compte tenu des difficultés liées à l'obtention de trous calibrés de petite taille (inférieure à 2 µm) sur de grandes surfaces.This is very advantageous considering the difficulties in obtaining calibrated holes from small size (less than 2 µm) over large areas.

BREVE DESCRIPTION DES DESSINSBRIEF DESCRIPTION OF THE DRAWINGS

La présente invention sera mieux comprise à la lecture de la description d'exemples de réalisation donnés ci-après, à titre purement indicatif et nullement limitatif, en faisant référence aux dessins annexés sur lesquels :

  • la figure 1 est une vue en coupe schématique d'une source d'électrons conforme à la présente invention,
  • la figure 2 est une vue en coupe schématique d'un dispositif de visualisation utilisant la source de la figure 1,
  • la figure 3 illustre schématiquement un procédé de fabrication d'une source d'électrons conforme à l'invention,
  • la figure 4 illustre schématiquement la possibilité d'utiliser des trous rectangulaires pour fabriquer une source conforme à l'invention, et
  • la figure 5 illustre schématiquement un autre procédé de fabrication d'une source d'électrons conforme à l'invention.
The present invention will be better understood on reading the description of exemplary embodiments given below, by way of purely indicative and in no way limiting, with reference to the appended drawings in which:
  • FIG. 1 is a schematic sectional view of an electron source according to the present invention,
  • FIG. 2 is a schematic sectional view of a display device using the source of FIG. 1,
  • FIG. 3 schematically illustrates a process for manufacturing an electron source according to the invention,
  • FIG. 4 schematically illustrates the possibility of using rectangular holes to manufacture a source according to the invention, and
  • Figure 5 schematically illustrates another method of manufacturing an electron source according to the invention.

EXPOSE DETAILLE DE MODES DE REALISATION PARTICULIERSDETAILED PRESENTATION OF PARTICULAR EMBODIMENTS

La source conforme à l'invention, qui est schématiquement représentée en coupe sur la figure 1, comprend :

  • sur un substrat électriquement isolant 2, des électrodes 4 jouant le rôle de conducteurs cathodiques (un seul conducteur cathodique est visible sur la figure 1),
  • une couche électriquement isolante 6 qui recouvre chaque conducteur cathodique, et
  • des électrodes 8 jouant le rôle de grilles et formées sur la couche électriquement isolante 6 (une seule grille est visible sur la figure 1).
The source according to the invention, which is schematically represented in section in FIG. 1, comprises:
  • on an electrically insulating substrate 2, electrodes 4 acting as cathode conductors (a single cathode conductor is visible in FIG. 1),
  • an electrically insulating layer 6 which covers each cathode conductor, and
  • electrodes 8 playing the role of grids and formed on the electrically insulating layer 6 (a single grid is visible in FIG. 1).

Des trous 10 sont formés à travers ces grilles 8 et la couche isolante 6 au-dessus des conducteurs cathodiques 4.Holes 10 are formed through these grids 8 and the insulating layer 6 above the cathode conductors 4.

Des micro-amas 12 contenant des particules de carbone diamant ou de type diamant, sont formés dans les trous 10 et portés par les conducteurs cathodiques 4.Micro-clusters 12 containing particles carbon diamond or diamond type, are formed in the holes 10 and carried by the cathode conductors 4.

On précise que les conducteurs cathodiques 4 sont parallèles et que les grilles 8 sont parallèles les unes aux autres et perpendiculaires aux conducteurs cathodiques 4. It is specified that the cathode conductors 4 are parallel and the grids 8 are parallel to each other and perpendicular to the conductors cathodic 4.

Les trous 10 et donc les micro-amas 12 se trouvent dans les zones où ces grilles croisent les conducteurs cathodiques.The holes 10 and therefore the micro-clusters 12 are are found in the areas where these grids cross the cathode conductors.

Ce sont les micro-amas d'une telle zone qui émettent des électrons lorsqu'une tension électrique appropriée est appliquée, par des moyens non représentés, entre le conducteur cathodique 4 et la grille 8 qui correspondent à cette zone.It is the micro-clusters in such an area that emit electrons when an electrical voltage appropriate is applied, by means not shown, between the cathode conductor 4 and the grid 8 which correspond to this zone.

Un dispositif de visualisation par cathodoluminescence est schématiquement représenté en coupe sur la figure 2.A display device by cathodoluminescence is schematically represented in section in Figure 2.

Ce dispositif comprend la source d'électrons 14 de la figure 1.This device includes the source of electrons 14 in Figure 1.

Le dispositif de la figure 2 comprend aussi une anode cathodoluminescente 16 placée en regard de la source 14 et séparée de celle-ci par un espace 18 dans lequel on a fait le vide.The device of Figure 2 also includes a cathodoluminescent anode 16 placed opposite the source 14 and separated from it by a space 18 in which we made the vacuum.

L'anode cathodoluminescente 16 comprend un substrat électriquement isolant et transparent 20 qui est pourvu d'une couche électriquement conductrice et transparente 22 formant une anode.The cathodoluminescent anode 16 comprises a electrically insulating and transparent substrate 20 which is provided with an electrically conductive layer and transparent 22 forming an anode.

Celle-ci est disposée en regard de la source d'électrons 14 et revêtue, en face de cette source, d'une couche 24 d'un matériau cathodoluminescent ou "luminophore" ("phosphor" dans les publications en langue anglaise).This is arranged opposite the electron source 14 and coated, opposite this source, a layer 24 of a material cathodoluminescent or "luminophore" ("phosphor" in English language publications).

Sous l'impact des électrons émis par les micro-amas 12 de la source, cette couche 24 émet une lumière qu'un utilisateur du dispositif de visualisation observe à travers le substrat transparent 20.Under the impact of electrons emitted by micro-cluster 12 of the source, this layer 24 emits a light that a user of the device visualization observed through the transparent substrate 20.

Il s'agit d'un dispositif que l'on peut comparer aux dispositifs de visualisation décrits dans les documents (1) à (4) mentionnés ci-après mais qui présente des avantages par rapport à ces dispositifs, comme on l'a vu plus haut :

  • (1) FR-A-2 593 953 correspondant à EP-A-0 234 989 et à US-A-4 857 161
  • (2) FR-A-2 623 013 correspondant à EP-A-0 316 214 et à US-A-4 940 916
  • (3) FR-A-2 663 462 correspondant à EP-A-0 461 990 et à US-A-5 194 780
  • (4) FR-A-2 687 839 correspondant à EP-A-0 558 393 et à la demande de brevet américain du 26 février 1993, numéro de série 08/022,935 (Leroux et al.).
    • It is a device that can be compared to the display devices described in documents (1) to (4) mentioned below, but which has advantages over these devices, as we have seen. upper :
  • (1) FR-A-2 593 953 corresponding to EP-A-0 234 989 and US-A-4 857 161
  • (2) FR-A-2 623 013 corresponding to EP-A-0 316 214 and to US-A-4 940 916
  • (3) FR-A-2 663 462 corresponding to EP-A-0 461 990 and US-A-5 194 780
  • (4) FR-A-2 687 839 corresponding to EP-A-0 558 393 and to the American patent application of February 26, 1993, serial number 08 / 022,935 (Leroux et al.).

    • On explique ci-après un procédé de fabrication de la source d'électrons de la figure 1 en se référant à la figure 3 qui illustre schématiquement ce procédé.We explain below a method of fabrication of the electron source of figure 1 in referring to Figure 3 which schematically illustrates this process.

    Pour fabriquer cette source, on commence par fabriquer une structure comprenant :

    • le substrat 2,
    • les conducteurs cathodiques 4,
    • la couche électriquement isolante 6,
    • une couche de grille 25, qui recouvre cette couche électriquement isolante 6, et
    • les trous 10 formés dans cette couche de grille 25 et la couche électriquement isolante 6.
    To make this source, we start by making a structure comprising:
    • the substrate 2,
    • cathode conductors 4,
    • the electrically insulating layer 6,
    • a grid layer 25, which covers this electrically insulating layer 6, and
    • the holes 10 formed in this grid layer 25 and the electrically insulating layer 6.

    La fabrication d'une telle structure est connue et, à ce sujet, on se reportera aux documents (1) à (4) mentionnés plus haut.The manufacture of such a structure is known and, on this subject, refer to the documents (1) to (4) mentioned above.

    On précise cependant que le diamètre D1 des trous (sensiblement circulaires) formés dans la grille 8 et dans la couche électriquement isolante 6 peut être avantageusement supérieur au diamètre des trous que comportent les sources d'électrons à micro-pointes décrites dans les documents (1) à (4).However, it should be noted that the diameter D1 of holes (substantially circular) formed in the grid 8 and in the electrically insulating layer 6 can be advantageously greater than the diameter of the holes than contain micro-point electron sources described in documents (1) to (4).

    Par exemple, ce diamètre D1 peut prendre des valeurs de l'ordre de 1 µm jusqu'à 20 µm.For example, this diameter D1 can take values on the order of 1 µm up to 20 µm.

    La figure 4 illustre schématiquement le fait que les trous 10, au lieu d'avoir une forme circulaire, peuvent avoir une forme rectangulaire.Figure 4 schematically illustrates the makes the holes 10, instead of having a shape circular, may have a rectangular shape.

    La largeur D2 de ces trous 10 de la figure 4, de forme rectangulaire, peut être prise égale au diamètre D1 mentionné plus haut et peut donc être également nettement supérieure au diamètre des trous des sources à micro-pointes.The width D2 of these holes 10 in the figure 4, rectangular, can be taken equal to diameter D1 mentioned above and can therefore be also significantly larger than the diameter of the holes micro-tip sources.

    Il s'agit ensuite de former dans les trous 10 les micro-amas 12 de carbone diamant ou de type diamant (après quoi on formera les grilles, perpendiculairement aux conducteurs cathodiques, par gravure de la couche de grille 25).It is then a question of forming in the holes 10 micro-clusters 12 of diamond or type carbon diamond (after which we will form the grids, perpendicular to the cathode conductors, by etching of the grid layer 25).

    Pour former les micro-amas 12, on utilise une poudre de carbone diamant ou de type diamant.To form micro-clusters 12, we use diamond or diamond-like carbon powder.

    Cette poudre peut être obtenue par dépôt chimique en phase vapeur, à partir d'un mélange d'hydrogène et d'hydrocarbures légers.This powder can be obtained by deposit chemical vapor phase, from a mixture hydrogen and light hydrocarbons.

    Ce dépôt chimique en phase vapeur peut être assisté par un faisceau d'électrons ou être assisté par un plasma engendré par des micro-ondes.This chemical vapor deposition can be assisted by an electron beam or be assisted by a plasma generated by microwaves.

    On peut également synthétiser cette poudre au moyen d'un laser, c'est-à-dire, plus précisément, par dépôt chimique en phase vapeur comme précédemment mais assisté par laser.We can also synthesize this powder by means of a laser, that is to say, more precisely, by chemical vapor deposition as before but assisted by laser.

    On peut également synthétiser la poudre par dépôt physique en phase vapeur ("physical vapour deposition"), à partir de cibles de carbone (graphite par exemple) et d'un gaz plasmagène tel que l'argon seul ou mélangé avec de l'hydrogène, des hydrocarbures sans dopant ou avec un dopant comme par exemple le diborane.The powder can also be synthesized by physical vapor deposition ("physical vapor" deposition "), from carbon targets (graphite for example) and a plasma gas such as argon alone or mixed with hydrogen, hydrocarbons without dopant or with a dopant like for example the diborane.

    On peut également obtenir cette poudre par ablation laser.This powder can also be obtained by laser ablation.

    On peut également utiliser une poudre de diamant naturel.You can also use a powder of natural diamond.

    En variante, on peut préparer des diamants artificiels par compactage de carbone, à haute pression et haute température, puis fabriquer la poudre à partir de ces diamants artificiels.Alternatively, diamonds can be prepared carbon compression, high pressure and high temperature, then make the powder from of these artificial diamonds.

    De préférence, ces poudres de carbone diamant et ces poudres de carbone de type diamant sont choisies de façon à avoir une granulométrie micronique ou submicronique, de préférence nanométrique.Preferably, these carbon powders diamond and these diamond-like carbon powders are chosen so as to have a micronic particle size or submicron, preferably nanometric.

    On précise que ces poudres de carbone diamant ou de type diamant peuvent être dopées ou non dopées.It is specified that these carbon powders diamond or diamond type can be doped or not doped.

    On peut par exemple utiliser le bore en tant que dopant.We can for example use boron in as a dopant.

    Le dépôt de la poudre (particules de carbone diamant ou de type diamant) conduisant à la formation des micro-amas 12 dans les trous 10, sur les conducteurs cathodiques 4, peut être réalisé par électrophorèse (cataphorèse ou anaphorèse), éventuellement complétée par un dépôt métallique électrochimique de consolidation, ou par co-dépôt électrochimique de métal et de carbone diamant ou de type diamant.The deposition of the powder (particles of diamond or diamond type) leading to the formation of micro-clusters 12 in holes 10, on the cathode conductors 4, can be realized by electrophoresis (cataphoresis or anaphoresis), possibly supplemented by a metallic deposit electrochemical consolidation, or by co-deposit electrochemical of metal and carbon diamond or diamond type.

    Dans le cas du dépôt par anaphorèse, la structure pourvue des trous 10 est placée dans une solution appropriée 26 et le fond de chaque trou 10 est porté à un potentiel positif pendant cette phase de dépôt.In the case of anaphoresis filing, the structure provided with holes 10 is placed in a appropriate solution 26 and the bottom of each hole 10 is brought to positive potential during this phase of deposit.

    Plus précisément, les conducteurs cathodiques 4 sont portés à ce potentiel positif grâce à une source de tension appropriée 28 dont la borne positive est reliée à ces conducteurs cathodiques 4 tandis que la borne négative de cette source est reliée à une contre-électrode 32 en platine ou en acier inoxydable située dans le bain à une distance du substrat d'environ 1 à 5 cm.Specifically, drivers cathodics 4 are brought to this positive potential thanks to a suitable voltage source 28 whose terminal positive is connected to these cathode conductors 4 while the negative terminal of this source is connected to a platinum or steel counter electrode 32 stainless steel located in the bath at a distance from substrate about 1 to 5 cm.

    La poudre fine de particules de carbone diamant ou de type diamant est mise en suspension dans la solution 26 (avant de placer la structure dans cette solution).The fine powder of carbon particles diamond or diamond type is suspended in solution 26 (before placing the structure in this solution).

    La solution 26 comporte par exemple :

    • de l'acétone,
    • un acide qui peut être de l'acide sulfurique à 8 µl par litre de solution, et
    • de la nitrocellulose qui joue le rôle de liant et de dispersant.
    Solution 26 includes for example:
    • acetone,
    • an acid which may be sulfuric acid at 8 μl per liter of solution, and
    • nitrocellulose which acts as a binder and dispersant.

    L'immersion de la structure dans cette solution et l'application du potentiel positif au fond des trous conduit à l'obtention des micro-amas 12.The immersion of the structure in this solution and application of the positive potential at the bottom holes leads to the obtaining of micro-clusters 12.

    La tension fournie par la source 28 peut aller jusqu'à environ 200 V.The voltage supplied by the source 28 can go up to around 200 V.

    Dans le cas de la cataphorèse, un potentiel négatif est appliqué au fond des trous.In the case of cataphoresis, a potential negative is applied to the bottom of the holes.

    Plus précisément, dans ce cas, c'est la borne négative de la source 28 qui est reliée aux conducteurs cathodiques 4 tandis que la borne positive de la source 28 est reliée à une contre-électrode 32 en platine ou en acier inoxydable située dans le bain à une distance du substrat d'environ 1 à 5 cm.Specifically, in this case, this is the source 28 negative terminal which is connected to cathode conductors 4 while the positive terminal of the source 28 is connected to a counter-electrode 32 in platinum or stainless steel located in the bath a distance from the substrate of about 1 to 5 cm.

    La solution 26 comporte alors par exemple :

    • de l'alcool isopropylique,
    • un liant minéral comme exemple Mg(NO3)2, 6H2O (de concentration 10-5 mole par litre), et
    • un dispersant tel que le glycérol (dont la concentration est de l'ordre de 1% en volume).
    The solution 26 then comprises for example:
    • isopropyl alcohol,
    • an inorganic binder, for example Mg (NO 3 ) 2 , 6H 2 O (of concentration 10 -5 moles per liter), and
    • a dispersant such as glycerol (the concentration of which is around 1% by volume).

    On utilise alors une tension pouvant aller jusqu'à 200 V environ.We then use a voltage that can go up to around 200 V.

    On obtient le même type de dépôt que dans le cas de l'anaphorèse.We obtain the same type of deposit as in the case of anaphoresis.

    Dans l'intention de consolider le dépôt obtenu par électrophorèse, on peut, après celui-ci, réaliser un dépôt électrochimique d'un métal par exemple choisi parmi Ni, Co, Ag, Au, Rh ou Pt ou, plus généralement, parmi les métaux de transition, les alliages de ceux-ci et les métaux précieux.With the intention of consolidating the deposit obtained by electrophoresis, we can, after this one, electrochemical deposition of a metal by example chosen from Ni, Co, Ag, Au, Rh or Pt or, more generally, among transition metals, alloys thereof and precious metals.

    Ceci est schématiquement illustré par la figure 5 où l'on voit la structure pourvue des micro-amas 12 et plongée dans une solution 30 permettant un tel dépôt électrochimique.This is schematically illustrated by the figure 5 where we see the structure provided with micro-clusters 12 and immersed in a solution 30 allowing a such electrochemical deposition.

    Une tension électrique appropriée est alors appliquée entre les conducteurs cathodiques 4 et une électrode 33 placée dans cette solution, au moyen d'une source de tension 34.An appropriate electrical voltage is then applied between the cathode conductors 4 and a electrode 33 placed in this solution, by means of a voltage source 34.

    Cette électrode 33 est par exemple en nickel et la solution 30 contient par exemple 300 g/l de sulfate de nickel, 30 g/l de chlorure de nickel, 30 g/l d'acide borique et 0,6 g/l de lauryl sulfate de sodium.This electrode 33 is for example in nickel and solution 30 contains for example 300 g / l nickel sulfate, 30 g / l nickel chloride, 30 g / l of boric acid and 0.6 g / l of lauryl sulfate sodium.

    On utilise par exemple un courant électrique de 4 A/dm2.For example, an electric current of 4 A / dm 2 is used .

    On voit sur la figure 5 le dépôt métallique 36 qui est formé sur chaque micro-amas 12 après cette opération de dépôt électrochimique, laissant apparaítre des parties émergeantes des particules du micro-amas.We see in Figure 5 the metallic deposit 36 which is formed on each micro-cluster 12 after this electrochemical deposition operation, revealing emerging parts of the micro-cluster particles.

    On peut également former les micro-amas par co-dépôt électrochimique de métal et de carbone diamant ou de type diamant.We can also form micro-clusters by electrochemical co-deposit of metal and carbon diamond or diamond type.

    Pour ce faire, on utilise par exemple un bain contenant des ions de nickel et de la poudre de diamant en suspension dans ce bain. To do this, we use for example a bath containing nickel ions and powder diamond suspended in this bath.

    On peut utiliser jusqu'à 60% en poids de diamant en suspension dans le bain.Up to 60% by weight of diamond suspended in the bath.

    On utilise une source de courant appropriée, par exemple de l'ordre de 4 A/dm2, et l'on applique la borne négative de cette source aux conducteurs cathodiques et la borne positive de cette source à une électrode de nickel placée dans le bain.An appropriate current source is used, for example of the order of 4 A / dm 2 , and the negative terminal of this source is applied to the cathode conductors and the positive terminal of this source to a nickel electrode placed in the bath.

    Le nickel se dépose dans les trous en entraínant avec lui les particules de diamant, d'où la formation de micro-amas de nickel et de diamant dans ces trous.Nickel is deposited in the holes in bringing with it the diamond particles, hence the formation of nickel and diamond micro-clusters in these holes.

    Bien entendu, les sommets des micro-amas (éventuellement recouverts d'un dépôt métallique de consolidation) se trouvent sensiblement dans le plan des grilles et ces micro-amas sont sans contact avec ces grilles.Of course, the tops of the micro-clusters (possibly covered of a metallic consolidation deposit) are found substantially in the plane of the grids and these micro-clusters are not in contact with these grids.

    Claims (10)

    1. Field effect electron source comprising:
      an electrically insulating substrate (2), at least one first electrode (4) serving as the cathode conductor,
      an electrically insulating layer (6) covering said cathode conductor,
      at least one second electrode (8) serving as the grid, formed on the electrically insulating layer, holes (10) being formed through said grid and the electrically insulating layer above the cathode conductor and
      elements (12) able to emit electrons and formed in these holes and carried by the cathode conductor,
      said source being characterized in that said elements are microheaps (12) composed of powder grains of carbon diamond or of the diamond type, which are in direct contact with their closest neighbours and/or interlinked by a metal.
    2. Source according to claim 1, characterized in that the microheaps (12) are formed from carbon diamond or diamond like carbon particles or are formed from such particles dispersed in a metal.
    3. Source according to claim 2, characterized in that the microheaps (12) are linked by a deposit of a metal, the carbon diamond or diamond like carbon particles emerging from said deposit on the surface of the microheaps.
    4. Cathodoluminescence display means comprising a field effect electron source (14) and a cathodoluminescent anode (16) comprising a cathodoluminescent material layer (24), characterized in that the source (14) is in accordance with any one of the claims 1 to 3.
    5. Process for the production of a field effect electron source in which:
      a structure comprising an electrically insulating substrate, at least one cathode conductor on said substrate (2), an electrically insulating layer (6) covering each cathode conductor (4) and an electrically conductive grid layer (25) covering said electrically insulating layer is produced,
      holes (10) are formed through the grid layer and the electrically insulating layer at each cathode conductor and
      in each hole is formed an element (12) able to emit electrons, said process being characterized in that the elements are microheaps (12) composed of powder grains of carbon diamond or of the diamond type, which are in direct contact with their closest neighbours and/or interlinked by a metal.
    6. Process according to claim 5, characterized in that the microheaps (12) formed by electrophoresis are then linked with the aid of a metal by electrochemical depositioni.
    7. Process according to either of the claims 5 and 6, characterized in that the carbon diamond or diamond like carbon particles have a size of approximately 1 µm or less than 1 µm.
    8. Process according to claim 7, characterized in that the particles are obtained from natural or artificial diamond or by a method chosen from among laser synthesis, chemical vapour deposition and physical vapour deposition.
    9. Process according to any one of the claims 5 to 8, characterized in that the holes (10) are circular or rectangular.
    10. Process according to any one of the claims 5 to 9, characterized in that the size of the holes (10) is chosen within a range from approximately 1 µm to several dozen micrometers.
    EP95402450A 1994-11-08 1995-11-03 Field effect electron source and method for producing same application in display devices working by cathodoluminescence Expired - Lifetime EP0712146B1 (en)

    Applications Claiming Priority (2)

    Application Number Priority Date Filing Date Title
    FR9413371A FR2726688B1 (en) 1994-11-08 1994-11-08 FIELD-EFFECT ELECTRON SOURCE AND MANUFACTURING METHOD THEREOF, APPLICATION TO CATHODOLUMINESCENCE VISUALIZATION DEVICES
    FR9413371 1994-11-08

    Publications (2)

    Publication Number Publication Date
    EP0712146A1 EP0712146A1 (en) 1996-05-15
    EP0712146B1 true EP0712146B1 (en) 1999-06-30

    Family

    ID=9468611

    Family Applications (1)

    Application Number Title Priority Date Filing Date
    EP95402450A Expired - Lifetime EP0712146B1 (en) 1994-11-08 1995-11-03 Field effect electron source and method for producing same application in display devices working by cathodoluminescence

    Country Status (5)

    Country Link
    US (1) US5828162A (en)
    EP (1) EP0712146B1 (en)
    JP (1) JPH08241664A (en)
    DE (1) DE69510521T2 (en)
    FR (1) FR2726688B1 (en)

    Families Citing this family (23)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    WO1997018576A1 (en) * 1995-11-15 1997-05-22 E.I. Du Pont De Nemours And Company Diamond powder field emitters and field emitter cathodes made therefrom
    WO1997018577A1 (en) * 1995-11-15 1997-05-22 E.I. Du Pont De Nemours And Company Process for making a field emitter cathode using a particulate field emitter material
    GB2322471A (en) * 1997-02-24 1998-08-26 Ibm Self stabilising cathode
    WO1999040601A1 (en) * 1998-02-09 1999-08-12 Matsushita Electric Industrial Co., Ltd. Electron emitting device, method of producing the same, and method of driving the same; and image display comprising the electron emitting device and method of producing the same
    JPH11329217A (en) * 1998-05-15 1999-11-30 Sony Corp Manufacture of field emission type cathode
    JP2000182508A (en) * 1998-12-16 2000-06-30 Sony Corp Field emission type cathode, electron emitting device, and manufacture of electron emitting device
    JP3595718B2 (en) * 1999-03-15 2004-12-02 株式会社東芝 Display element and method of manufacturing the same
    JP2000306492A (en) * 1999-04-21 2000-11-02 Hitachi Powdered Metals Co Ltd Field emission cathode, electron emission device, and manufacture of electron emission device
    EP1073090A3 (en) * 1999-07-27 2003-04-16 Iljin Nanotech Co., Ltd. Field emission display device using carbon nanotubes and manufacturing method thereof
    JP2001043790A (en) * 1999-07-29 2001-02-16 Sony Corp Manufacture of cold cathode electric field electron emitting element, and manufacture of cold cathode electric field electron emitting display device
    US6342755B1 (en) * 1999-08-11 2002-01-29 Sony Corporation Field emission cathodes having an emitting layer comprised of electron emitting particles and insulating particles
    GB9919737D0 (en) * 1999-08-21 1999-10-20 Printable Field Emitters Limit Field emitters and devices
    US6384520B1 (en) 1999-11-24 2002-05-07 Sony Corporation Cathode structure for planar emitter field emission displays
    JP2001185019A (en) 1999-12-27 2001-07-06 Hitachi Powdered Metals Co Ltd Electron emission cathode, electron emission device, and method of manufacturing electron emission device
    JP3953276B2 (en) * 2000-02-04 2007-08-08 株式会社アルバック Graphite nanofiber, electron emission source and manufacturing method thereof, display element having the electron emission source, and lithium ion secondary battery
    JP3730476B2 (en) 2000-03-31 2006-01-05 株式会社東芝 Field emission cold cathode and manufacturing method thereof
    KR100366705B1 (en) * 2000-05-26 2003-01-09 삼성에스디아이 주식회사 Method for fabricating a carbon nanotube-based emitter using an electrochemical polymerization
    WO2002103737A2 (en) * 2001-06-14 2002-12-27 Hyperion Catalysis International, Inc. Field emission devices using ion bombarded carbon nanotubes
    US7210978B2 (en) * 2004-04-14 2007-05-01 Teco Nanotech Co., Ltd. Electron-emission type field-emission display and method of fabricating the same
    CN100405523C (en) * 2004-04-23 2008-07-23 清华大学 Field emission display
    US7736209B2 (en) * 2004-09-10 2010-06-15 Applied Nanotech Holdings, Inc. Enhanced electron field emission from carbon nanotubes without activation
    CN100370571C (en) * 2004-11-12 2008-02-20 清华大学 Field emission cathode and field emission apparatus
    TWI309843B (en) * 2006-06-19 2009-05-11 Tatung Co Electron emission source and field emission display device

    Family Cites Families (12)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    US2293593A (en) 1941-07-25 1942-08-18 Albert Shelby Hair treating apparatus
    US4084942A (en) * 1975-08-27 1978-04-18 Villalobos Humberto Fernandez Ultrasharp diamond edges and points and method of making
    FR2593953B1 (en) * 1986-01-24 1988-04-29 Commissariat Energie Atomique METHOD FOR MANUFACTURING A DEVICE FOR VIEWING BY CATHODOLUMINESCENCE EXCITED BY FIELD EMISSION
    FR2623013A1 (en) 1987-11-06 1989-05-12 Commissariat Energie Atomique ELECTRO SOURCE WITH EMISSIVE MICROPOINT CATHODES AND FIELD EMISSION-INDUCED CATHODOLUMINESCENCE VISUALIZATION DEVICE USING THE SOURCE
    US5225820A (en) * 1988-06-29 1993-07-06 Commissariat A L'energie Atomique Microtip trichromatic fluorescent screen
    FR2663462B1 (en) 1990-06-13 1992-09-11 Commissariat Energie Atomique SOURCE OF ELECTRON WITH EMISSIVE MICROPOINT CATHODES.
    JP3255960B2 (en) * 1991-09-30 2002-02-12 株式会社神戸製鋼所 Cold cathode emitter element
    US5199918A (en) * 1991-11-07 1993-04-06 Microelectronics And Computer Technology Corporation Method of forming field emitter device with diamond emission tips
    US5252833A (en) * 1992-02-05 1993-10-12 Motorola, Inc. Electron source for depletion mode electron emission apparatus
    FR2687839B1 (en) 1992-02-26 1994-04-08 Commissariat A Energie Atomique ELECTRON SOURCE WITH MICROPOINT EMISSIVE CATHODES AND FIELD EMISSION-EXCITED CATHODOLUMINESCENCE VISUALIZATION DEVICE USING THE SOURCE.
    US5289086A (en) * 1992-05-04 1994-02-22 Motorola, Inc. Electron device employing a diamond film electron source
    US5473218A (en) * 1994-05-31 1995-12-05 Motorola, Inc. Diamond cold cathode using patterned metal for electron emission control

    Also Published As

    Publication number Publication date
    EP0712146A1 (en) 1996-05-15
    DE69510521D1 (en) 1999-08-05
    DE69510521T2 (en) 2000-03-16
    FR2726688A1 (en) 1996-05-10
    JPH08241664A (en) 1996-09-17
    US5828162A (en) 1998-10-27
    FR2726688B1 (en) 1996-12-06

    Similar Documents

    Publication Publication Date Title
    EP0712146B1 (en) Field effect electron source and method for producing same application in display devices working by cathodoluminescence
    EP0712147B1 (en) Field-effect electron source and manufacturing method; application in display devices with cathodoluminescence
    EP1614765B1 (en) Low temperature growth of oriented carbon nanotubes
    US6462467B1 (en) Method for depositing a resistive material in a field emission cathode
    EP0717877B1 (en) Fabrication of electron-emitting devices having high emitter packing density
    KR101000827B1 (en) Electron-emitting device, electron source using the same, image display apparatus, and information displaying and reproducing apparatus
    WO2001011647A1 (en) Field emission cathodes comprised of electron emitting particles and insulating particles
    FR2723255A1 (en) Field emission display device
    CN1266536A (en) Carbon film for field emission device
    EP0708473B1 (en) Manufacturing method for micropoint electron source
    EP0697710B1 (en) Manufacturing method for a micropoint-electron source
    EP0802559B1 (en) Flat panel display with hydrogen source
    EP0856868B1 (en) Field emission electron source and display device with such a source
    WO1998025291A1 (en) Display screen comprising a source of electrons with microtips, capable of being observed through the microtip support, and method for making this source
    US6593683B1 (en) Cold cathode and methods for producing the same
    FR2759202A1 (en) ELECTRON-EMITTING DEVICE AND DISPLAY DEVICE PROVIDED WITH SUCH A DEVICE
    JPH06131968A (en) Field emission type electron source and array substrate
    EP1932806B1 (en) Method for manufacturing carbon nanotubes with metal cores
    FR2719155A1 (en) Micro-tip field emitter cathode for flat screen
    EP1971703A2 (en) Catalytic and directional growth of individual carbon nanotubes, and application thereof for cold electron sources
    WO2002006559A1 (en) Method for making carbon films capable of emitting electrons, by chemical vapour deposition
    Boscolo et al. Tests on diamond films as current amplifiers for photocathodes
    Janik et al. Electron emission from diamond layer on tungsten wire measured in cylindrical electrode configuration
    FR2721751A1 (en) Process for producing microtips with controlled composition over large areas
    FR2779243A1 (en) METHOD FOR REALIZING SELF-ALIGNED OPENINGS ON A STRUCTURE BY PHOTOLITHOGRAPHY, PARTICULARLY FOR MICROPOINT FLAT SCREEN

    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

    Kind code of ref document: A1

    Designated state(s): DE GB IT

    17P Request for examination filed

    Effective date: 19961022

    GRAG Despatch of communication of intention to grant

    Free format text: ORIGINAL CODE: EPIDOS AGRA

    17Q First examination report despatched

    Effective date: 19981008

    GRAG Despatch of communication of intention to grant

    Free format text: ORIGINAL CODE: EPIDOS AGRA

    GRAH Despatch of communication of intention to grant a patent

    Free format text: ORIGINAL CODE: EPIDOS IGRA

    GRAH Despatch of communication of intention to grant a patent

    Free format text: ORIGINAL CODE: EPIDOS IGRA

    GRAA (expected) grant

    Free format text: ORIGINAL CODE: 0009210

    AK Designated contracting states

    Kind code of ref document: B1

    Designated state(s): DE GB IT

    REF Corresponds to:

    Ref document number: 69510521

    Country of ref document: DE

    Date of ref document: 19990805

    ITF It: translation for a ep patent filed

    Owner name: JACOBACCI & PERANI S.P.A.

    GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

    Effective date: 19990903

    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
    REG Reference to a national code

    Ref country code: GB

    Ref legal event code: IF02

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

    Ref country code: DE

    Payment date: 20031121

    Year of fee payment: 9

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

    Ref country code: GB

    Payment date: 20041104

    Year of fee payment: 10

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

    Ref country code: DE

    Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

    Effective date: 20050601

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

    Ref country code: IT

    Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

    Effective date: 20051103

    Ref country code: GB

    Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

    Effective date: 20051103

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

    Effective date: 20051103