EP1154456A2 - Plasma display panel with protective layer - Google Patents

Plasma display panel with protective layer Download PDF

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Publication number
EP1154456A2
EP1154456A2 EP01000140A EP01000140A EP1154456A2 EP 1154456 A2 EP1154456 A2 EP 1154456A2 EP 01000140 A EP01000140 A EP 01000140A EP 01000140 A EP01000140 A EP 01000140A EP 1154456 A2 EP1154456 A2 EP 1154456A2
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Prior art keywords
plasma
protective layer
plate
gas
layer
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EP01000140A
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German (de)
French (fr)
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EP1154456A3 (en
Inventor
Peter Klaus Philips C.I.Prop.GMBH Bachmann
Volker c/o Philips C.I.Prop.GMBH van Elsbergen
Markus c/o Philips C.I.Prop.GMBH Klein
Rob c/o Phlips C.I.Prop.GMBH Snijkers
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Philips Intellectual Property and Standards GmbH
Koninklijke Philips NV
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Philips Corporate Intellectual Property GmbH
Koninklijke Philips Electronics NV
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Publication of EP1154456A2 publication Critical patent/EP1154456A2/en
Publication of EP1154456A3 publication Critical patent/EP1154456A3/en
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J11/00Gas-filled discharge tubes with alternating current induction of the discharge, e.g. alternating current plasma display panels [AC-PDP]; Gas-filled discharge tubes without any main electrode inside the vessel; Gas-filled discharge tubes with at least one main electrode outside the vessel
    • H01J11/10AC-PDPs with at least one main electrode being out of contact with the plasma
    • H01J11/12AC-PDPs with at least one main electrode being out of contact with the plasma with main electrodes provided on both sides of the discharge space
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J11/00Gas-filled discharge tubes with alternating current induction of the discharge, e.g. alternating current plasma display panels [AC-PDP]; Gas-filled discharge tubes without any main electrode inside the vessel; Gas-filled discharge tubes with at least one main electrode outside the vessel
    • H01J11/20Constructional details
    • H01J11/34Vessels, containers or parts thereof, e.g. substrates
    • H01J11/40Layers for protecting or enhancing the electron emission, e.g. MgO layers

Definitions

  • the invention relates to a plasma screen equipped with a front panel, the one Glass plate on which a dielectric layer and a protective layer are applied, has, equipped with a support plate with a phosphor layer, with a Rib structure that divides the space between the front plate and the support plate in plasma cells are filled with a gas, divides, and with one or more electrode arrays the front plate and the carrier plate for generating silent electrical discharges in the plasma cells.
  • Plasma screens enable color images with high resolution, large screen diagonals and are of compact design.
  • a plasma screen has a hermetic closed glass cell, which is filled with a gas, arranged with a grid Electrodes on. Applying an electrical voltage causes a gas discharge which mainly produces light in the vacuum ultraviolet range. By This VUV light is converted into visible light by luminescent materials Front panel of the glass cell emitted to the viewer.
  • Plasma screens are divided into two classes: DC plasma screens and AC plasma screens. With the DC plasma screens, the electrodes are in the direct Contact with the plasma. ' In AC plasma screens, the electrodes are through a the dielectric layer is separated from the plasma.
  • the gas discharge is ignited and maintained at the intersection of two electrodes on the front and the carrier plate.
  • the coplanar arrangement the gas discharge is maintained between the electrodes on the front plate and ignited at the point of intersection with an electrode, a so-called address electrode, on the carrier plate.
  • the address electrode is located under the phosphor layer.
  • the dielectric layer is still covered with a layer of MgO.
  • MgO has a high ion-induced secondary electron emission coefficient and thus reduces the ignition voltage of the gas.
  • MgO is resistant to sputtering due to positively charged ions in the plasma. The disadvantage is that during the manufacturing process, MgO can easily be contaminated with foreign substances that can hardly be removed again.
  • JP 11054048 A of the Patent Abstracts of Japan describes an AC plasma screen, a protective layer instead of a protective MgO layer on the dielectric layer made of diamond-like carbon (amorphous diamond).
  • the protective layer has an amorphous structure and is by means of a CVD (Chemical Vapor Deposition) process.
  • a disadvantage of using diamond-like carbon in the protective layer is that in the rigid conditions, for example high temperatures, in the manufacture of plasma screens diamond-like carbon change its structure and can also partially release hydrogen.
  • a disadvantage of the structural change is that this creates a layer with a graphite component, which turns brown. This reduces the luminance of the plasma screen. Released hydrogen can Change gas phase inside the plasma screen, causing, for example, the ignition voltage can be changed uncontrollably.
  • the object of the invention is to provide an improved plasma screen.
  • a plasma screen equipped with a front panel which is a glass plate on which a dielectric layer and a protective layer are applied are equipped with a carrier plate with a phosphor layer, with a rib structure that divides the space between the front plate and the carrier plate in plasma cells, which are filled with a gas, with one or more electrode arrays on the front plate and the support plate for the production of silent electrical Discharges in the plasma cells, in which the protective layer selects a material the group of crystalline diamond, AlN, AlGaN, BN and tetrahedral amorphous carbon contains.
  • These materials have a high chemical resistance, for example against high temperatures when manufacturing the plasma screen and they are not compared to MgO hygroscopic. They also assign higher physical resistance compared to diamond-like carbon and are, for example, more sputter-resistant high-energy plasma components. It also contains a protective layer of one these materials have no significant hydrogen content and a change in the gas phase in the discharge cells due to the release of hydrogen is prevented.
  • the gas contains xenon in a proportion of more than 7% by volume.
  • a protective layer made of crystalline diamond, AlN, AlGaN, BN or tetrahedral amorphous Carbon enables an increase in the xenon content in the gas without drastic Rise in ignition temperature.
  • By increasing the proportion of UV light generating Xenon in the gas becomes the UV light yield and thus the excitation of the phosphors more efficient.
  • the front panel 1 contains a glass plate 3 on which a dielectric layer 4 and one on top Protective layer 5 are applied.
  • the dielectric layer 4 is made, for example, of PbO-containing Glass.
  • Parallel, strip-shaped discharge electrodes are on the glass plate 3 6.7 applied, which are covered by the dielectric layer 4
  • the discharge electrodes For example, 6.7 are made of metal or ITO.
  • the carrier plate 2 is made of glass and the carrier plate 2 are parallel, strip-shaped, perpendicular to the discharge electrodes 6.7 extending address electrodes 10 made of Ag, for example. These are from a phosphor layer 9, which emits red, green or blue in one of the three basic colors, covered.
  • the individual plasma cells have a rib structure 12 with separating ribs separated from preferably dielectric material.
  • a gas preferably a noble gas mixture of, for example, He, Ne or Kr, which is used as component Xe to generate UV light contains.
  • a plasma is formed in the plasma region 8, through which, depending on the composition of the gas, radiation 11 in the UV region, in particular in the VUV region Area that is created.
  • This radiation 11 stimulates the phosphor layer 9 to emit light, which emits visible light 13 in one of the three primary colors, which emerges through the front panel 1 and thus represents a luminous pixel on the screen.
  • BaMgAl 10 O 17 : Eu for example, can be used as the blue-emitting phosphor, Zn 2 SiO 4 : Mn, for example, as the green-emitting phosphor and (Y, Gd) BO 3 : Eu as the red-emitting phosphor.
  • the dielectric layer 4 over the transparent discharge electrodes 6,7 serves below other with AC plasma screens, a direct discharge between the conductive Material existing discharge electrodes 6.7 and thus the formation of a To prevent the arc from igniting the discharge.
  • a front panel 1 with a protective layer 5 are first on a Glass plate 3, the size of which corresponds to the desired screen size, by means of vapor deposition and subsequent structuring, the discharge electrodes 6, 7 are applied.
  • the dielectric layer 4 is then applied and dried.
  • a protective layer 5 which are known per se.
  • a protective layer 5, the crystalline diamond contains, can be made by CVD methods.
  • This is a gas mixture that usually carbon and hydrogen and optionally oxygen, noble gases or Halogens contains, broken down into reactive radicals and molecular fragments that make up deposits a diamond film on a hot substrate.
  • the gas mixture can be excited for example by a plasma, a hot wire, an arc discharge or a chemical flame such as an acetylene-oxygen flame.
  • a protective layer 5, which contains AlN, can be made from an Al target by means of reactive sputtering be made in a nitrogenous atmosphere.
  • a protective layer 5, which contains AlN or AlGaN can also by means of MO (metal organic) CVD or via Plasma CVD can be produced. Appropriate metal-organic compounds either thermally or using a plasma in the presence of a nitrogen source stimulated and implemented.
  • a protective layer 5, which contains BN, by means of CVD or reactive Sputtering are made.
  • suitable boron-organic compounds applications are made.
  • BN-containing layers can be supported by ion beam Separation techniques are manufactured.
  • the BN can be cubic or hexagonal Have crystal lattices.
  • a protective layer 5, which contains tetrahedral amorphous carbon (t-a: C), can For example, using a filtered arc discharge made of graphite or using CVD techniques getting produced.
  • the layer thickness of the protective layer 5 is preferably between 2 nm and 10 ⁇ m. Layer thicknesses between 5 nm and 1 ⁇ m are very particularly preferred.
  • the entire front panel 1 is aftertreated and treated at 100 to 600 ° C for two hours together with a carrier plate 2 made of glass, which has a rib structure 12, conductive Has address electrodes 10 and a phosphor layer 9, and a gas for construction of an AC plasma display.
  • the gas preferably contains a noble gas mixture such as Ne / Xe, He / Xe or Ne / He / Xe, the proportion of xenon in the gas being preferred is at least 7% by volume.
  • the gas can also contain pure xenon. The higher the The content of xenon that generates UV light, the more efficient the UV light yield and thus the excitation of the phosphors.
  • the protective layer 5 which contains a material with low electron affinity, is lowered the ignition and operating voltages of the plasma. So the effect that with increasing Xenon content increases the ignition voltage of the plasma to be partially compensated and inexpensive driver electronics can be used in the plasma screen.
  • a diamond film was applied to the protective layer 5 dielectric layer 4 of a front plate 1, which is a glass plate 3, a dielectric Layer 4 and two discharge electrodes 6.7, applied.
  • the dielectric Layer 4 contained PbO and the two discharge electrodes 6, 7 were made of ITO.
  • the Layer thickness of the protective layer 5 made of crystalline diamond was 0.5 ⁇ m.
  • the entire front panel 1 was aftertreated and treated at 200 to 400 ° C for two hours then together with a carrier plate 2 made of glass, which has a rib structure 12, Has address electrodes 10 made of Ag and a phosphor layer 9, and a gas mixture, which had a composition of 7% by volume Xe and 93% by volume Ne, to Construction of an AC plasma display used, which had increased luminance.
  • a layer of AlN was applied to the dielectric layer 4 as a protective layer 5 a front plate 1, which has a glass plate 3, a dielectric layer 4 and two discharge electrodes 6.7, applied.
  • the dielectric layer 4 contained PbO and the two discharge electrodes 6, 7 were made of ITO.
  • the layer thickness of the protective layer 5 was 0.3 ⁇ m.
  • the entire front panel 1 was aftertreated and treated at 200 to 400 ° C for two hours then together with a carrier plate 2 made of glass, which has a rib structure 12, Has address electrodes 10 made of Ag and a phosphor layer 9, and a gas mixture, which had a composition of 20% by volume Xe and 80% by volume Ne, to Construction of a plasma screen used, which had increased luminance.

Abstract

Protective layer of the plasma screen is made from crystalline diamond, aluminum nitride, aluminum gallium nitride, boron nitride and tetrahedral amorphous carbon. Plasma screen comprises a front plate (1) with a glass plate (3) on which a dielectric layer (4) and a protective layer (5) are applied; a support plate (2) equipped with a phosphor layer (9); a ribbed structure (12) which divides the space between the front plate and the support plate into plasma cells which are filled with a gas; and electrode arrays (6, 7, 10) arranged on the front plate and the support plate for producing quiet electrical discharges in the plasma cells. Preferred Features: The gas is xenon in an amount of over 7 volume %.

Description

Die Erfindung betrifft einen Flasmabildschirm ausgerüstet mit einer Frontplatte, die eine Glasplatte, auf der eine dielektrische Schicht und eine Schutzschicht aufgebracht sind, aufweist, mit einer Trägerplatte ausgestattet mit einer Leuchtstoffschicht, mit einer Rippenstruktur, die den Raum zwischen Frontplatte und Trägarplatte in Plasmazellen, die mit einem Gas gefüllt sind, aufteilt, und mit einem oder mehreren Elektroden-Arrays auf der Frontplatte und der Trägerplatte zur Erzeugung von stillen elektrischen Entladungen in den Plasmazellen.The invention relates to a plasma screen equipped with a front panel, the one Glass plate on which a dielectric layer and a protective layer are applied, has, equipped with a support plate with a phosphor layer, with a Rib structure that divides the space between the front plate and the support plate in plasma cells are filled with a gas, divides, and with one or more electrode arrays the front plate and the carrier plate for generating silent electrical discharges in the plasma cells.

Plasmabildschirme ermöglichen Farbbilder mit hoher Auflösung, großer Bildschirmdiagonalen und sind von kompakter Bauweise. Ein Plasmabildschirm weist eine hermetisch abgeschlossene Glaszelle, die mit einem Gas gefüllt ist, mit gitterförmig angeordneten Elektroden auf. Durch Anlegen einer elektrischen Spannung wird eine Gasentladung hervorgerufen, die hauptsächlich licht im Vakuum-Ultraviolett-Bereich erzeugt. Durch Leuchtstoffe wird dieses VUV-Licht in sichtbares licht umgewandelt und durch die Frontplatte der Glaszelle zum Betrachter emittiert.Plasma screens enable color images with high resolution, large screen diagonals and are of compact design. A plasma screen has a hermetic closed glass cell, which is filled with a gas, arranged with a grid Electrodes on. Applying an electrical voltage causes a gas discharge which mainly produces light in the vacuum ultraviolet range. By This VUV light is converted into visible light by luminescent materials Front panel of the glass cell emitted to the viewer.

Plasmabildschirme werden in zwei Klassen unterteilt: DC-Plasmabildschirme und AC-Plasmabildschirme. Bei den DC-Plasmabildschirmen stehen die Elektroden im direkten Kontakt mit dem Plasma.' Bei AC-Plasmabildschirmen sind die Elektroden durch eine dielekbische Schicht von dem Plasma getrennt.Plasma screens are divided into two classes: DC plasma screens and AC plasma screens. With the DC plasma screens, the electrodes are in the direct Contact with the plasma. ' In AC plasma screens, the electrodes are through a the dielectric layer is separated from the plasma.

Prinzipiell unterscheidet man zwei Typen von AC-Plasmabildschirmen: eine Matrixanordnung und eine koplanare Anordnung der Elektroden-Arrays. Bei der Matrixanordnung wird die Gasentladung am Kreuzungspunkt zweier Elektroden auf der Front- und der Trägerplatte gezündet und unterhalten. Bei der koplanaren Anordnung wird die Gasentladung zwischen den Elektroden auf der Frontplatte unterhalten und am Kreuzungspunkt mit einer Elektrode, einer sogenannten Adresselektrode, auf der Trägerplatte gezündet. Die Adresselektrode befindet sich in diesem Fall unter der Leuchtstoffschicht.
In einem typischen AC-Plasmabildschirm ist die dielektrische Schicht noch mit einer Schicht aus MgO überschichtet. MgO besitzt einen hohen ioneninduzierten Sekundärelektronenemissionskoeffizienten und verringert so die Zündspannung des Gases Außerdem ist MgO resistent gegen Sputtering durch positiv geladene Ionen des Plasmas. Nachteilig ist, dass MgO während des Herstellungsprozess leicht mit Fremdstoffen kontaminiert werden kann, welche kaum wieder entfernbar sind.
A basic distinction is made between two types of AC plasma screens: a matrix arrangement and a coplanar arrangement of the electrode arrays. In the matrix arrangement, the gas discharge is ignited and maintained at the intersection of two electrodes on the front and the carrier plate. In the coplanar arrangement, the gas discharge is maintained between the electrodes on the front plate and ignited at the point of intersection with an electrode, a so-called address electrode, on the carrier plate. In this case, the address electrode is located under the phosphor layer.
In a typical AC plasma display screen, the dielectric layer is still covered with a layer of MgO. MgO has a high ion-induced secondary electron emission coefficient and thus reduces the ignition voltage of the gas. In addition, MgO is resistant to sputtering due to positively charged ions in the plasma. The disadvantage is that during the manufacturing process, MgO can easily be contaminated with foreign substances that can hardly be removed again.

In JP 11054048 A der Patent Abstracts of Japan wird ein AC-Plasmabildschirm beschrieben, der auf der dielektrischen Schicht anstelle einer MgO-Schutzschicht eine Schutzschicht aus diamant-ähnlichem Kohlenstoff (amorpher Diamant) aufweist. Die Schutzschicht weist eine amorphe Struktur auf und wird mittels eines CVD(Chemical Vapour Deposition)-Verfahrens abgeschieden.JP 11054048 A of the Patent Abstracts of Japan describes an AC plasma screen, a protective layer instead of a protective MgO layer on the dielectric layer made of diamond-like carbon (amorphous diamond). The protective layer has an amorphous structure and is by means of a CVD (Chemical Vapor Deposition) process.

Nachteilig bei Verwendung von diamant-ähnlichem Kohlenstoff in der Schutzschicht ist, dass bei den rigiden Bedingungen, zum Beispiel hohe Temperaturen, bei der Herstellung von Plamabildschirmen diamant-ähnlicher Kohlenstoff seine Struktur verändern und teilweise auch Wasserstoff abgeben kann. Ein Nachteil der Strukturveränderung ist, dass sich dadurch eine Schicht mit graphitischem Anteil bildet, welche sich bräunlich verfärbt. Dies verringert die Luminanz des Plasmabildschirms. Abgegebener Wasserstoff kann die Gasphase im Inneren des Plasmabildschirms verändern, wodurch beispielsweise die Zündspannung unkontrolliert verändert werden kann.A disadvantage of using diamond-like carbon in the protective layer is that in the rigid conditions, for example high temperatures, in the manufacture of plasma screens diamond-like carbon change its structure and can also partially release hydrogen. A disadvantage of the structural change is that this creates a layer with a graphite component, which turns brown. This reduces the luminance of the plasma screen. Released hydrogen can Change gas phase inside the plasma screen, causing, for example, the ignition voltage can be changed uncontrollably.

Der Erfindung liegt die Aufgabe zugrunde, einen verbesserten Plasmabildschirm bereitzustellen.The object of the invention is to provide an improved plasma screen.

Diese Aufgabe wird gelöst, durch einen Plasmabildschirm ausgerüstet mit einer Frontplatte, die eine Glasplatte, auf der eine dielektrische Schicht und eine Schutzschicht aufgebracht sind, aufweist, mit einer Trägerplatte ausgestattet mit einer Leuchtstoffschicht, mit einer Rippenstruktur, die den Raum zwischen Frontplatte und Trägerplatte in Plasmazellen, die mit einem Gas gefüllt sind, aufteilt, mit einem oder mehreren Elektroden-Arrays auf der Frontplatte und der Trägerplatte zur Erzeugung von stillen elektrischen Entladungen in den Plasmazellen, bei dem die Schutzschicht ein Material ausgswählt aus der Gruppe kristalliner Diamant, AlN, AlGaN, BN und tetrahedral amorpher Kohlenstoff enthält.This task is solved by a plasma screen equipped with a front panel, which is a glass plate on which a dielectric layer and a protective layer are applied are equipped with a carrier plate with a phosphor layer, with a rib structure that divides the space between the front plate and the carrier plate in plasma cells, which are filled with a gas, with one or more electrode arrays on the front plate and the support plate for the production of silent electrical Discharges in the plasma cells, in which the protective layer selects a material the group of crystalline diamond, AlN, AlGaN, BN and tetrahedral amorphous carbon contains.

Diese Materialien weisen eine hohe chemische Resistenz beispielsweise gegen hohe Temperaturen bei Herstellung des Plasmabildschirms auf und sie sind im Vergleich zu MgO nicht hygroskopisch. Sie weisen auch eine höhere physikalische Resistenz im Vergleich zu diamant-ähnlichem Kohlenstoff auf und sind beispielsweise sputter -resistenter gegenüber hochenergetischen Plasmabestandteilen. Außerdem enthält eine Schutzschicht aus einem dieser Materialien keine wesentlichen Wasserstoffanteile und eine Veränderung der Gasphase in den Entladungszellen durch Abgabe von Wasserstoff wird verhindert.These materials have a high chemical resistance, for example against high temperatures when manufacturing the plasma screen and they are not compared to MgO hygroscopic. They also assign higher physical resistance compared to diamond-like carbon and are, for example, more sputter-resistant high-energy plasma components. It also contains a protective layer of one these materials have no significant hydrogen content and a change in the gas phase in the discharge cells due to the release of hydrogen is prevented.

Es ist weiterhin bevorzugt, dass das Gas Xenon in einem Anteil von über 7 Vol.-% enthält.It is further preferred that the gas contains xenon in a proportion of more than 7% by volume.

Eine Schutzschicht aus kristallinem Diamant, AlN, AlGaN, BN oder tetrahedral amorphem Kohlenstoff ermöglicht eine Erhöhung des Xenon-Anteils im Gas ohne drastisches Ansteigen der Zündtemperatur. Durch Erhöhung des Anteils an UV-Licht generierendem Xenon im Gas wird die UV-Lichtausbeute und damit die Anregung der Leuchtstoffe effizienter.A protective layer made of crystalline diamond, AlN, AlGaN, BN or tetrahedral amorphous Carbon enables an increase in the xenon content in the gas without drastic Rise in ignition temperature. By increasing the proportion of UV light generating Xenon in the gas becomes the UV light yield and thus the excitation of the phosphors more efficient.

Im folgenden soll anhand von einer Figur und zwei Ausführungsbeispielen die Erfindung näher erläutert werden. Dabei zeigt

Fig. 1
den Aufbau und das Funktionsprinzip einer einzelnen Plasmazelle in einem AC-Plasmabildschirm.
The invention will be explained in more detail below with reference to a figure and two exemplary embodiments. It shows
Fig. 1
the structure and principle of operation of a single plasma cell in an AC plasma screen.

Gemäß Fig 1 weist eine Plasmazelle eines AC-Plasmabildschirms mit einer koplanaren Anordnung der Elektroden eine Frontplatte 1 und eine Trägerplatte 2 auf. Die Frontplatte 1 enthält eine Glasplatte 3, auf der eine dielektrische Schicht 4 und darauf eine Schutzschicht 5 aufgebracht sind Die dielektrische Schicht 4 ist beispielsweise aus PbO-haltigem Glas. Auf die Glasplatte 3 sind parallele, streifenförmige Entladungselektroden 6,7 aufgebracht, die von der dielektrischen Schicht 4 bedeckt sind Die Entladungselektroden 6,7 sind zum Beispiel aus Metall oder ITO. Die Trägerplatte 2 ist aus Glas und auf der Trägerplatte 2 sind parallele, streifenförmige, senkrecht zu den Entladungselektroden 6,7 verlaufende Adresselektroden 10 aus beispielsweise Ag aufgebracht. Diese sind von einer Leuchtstoffschicht 9, die in einer der drei Grundfatben rot, grün oder blau emittiert, bedeckt. Die einzelnen Plasmazellen sind durch eine Rippenstruktur 12 mit Trennrippen aus vorzugsweise dielektrischem Material getrennt.1 shows a plasma cell of an AC plasma screen with a coplanar Arrangement of the electrodes on a front plate 1 and a carrier plate 2. The front panel 1 contains a glass plate 3 on which a dielectric layer 4 and one on top Protective layer 5 are applied. The dielectric layer 4 is made, for example, of PbO-containing Glass. Parallel, strip-shaped discharge electrodes are on the glass plate 3 6.7 applied, which are covered by the dielectric layer 4 The discharge electrodes For example, 6.7 are made of metal or ITO. The carrier plate 2 is made of glass and the carrier plate 2 are parallel, strip-shaped, perpendicular to the discharge electrodes 6.7 extending address electrodes 10 made of Ag, for example. These are from a phosphor layer 9, which emits red, green or blue in one of the three basic colors, covered. The individual plasma cells have a rib structure 12 with separating ribs separated from preferably dielectric material.

In der Plasmazelle, das heißt zwischen den Entladungselektroden 6,7, von denen jeweils eine im Wechsel als Kathode bzw. Anode wirkt, befindet sich ein Gas, vorzugsweise ein Edelgasgemisch aus beispielsweise He, Ne oder Kr, welches als UV-Licht generierende Komponente Xe enthält. Nach Zündung der Oberflächenentladung, wodurch Ladungen auf einem zwischen den Entladungselektroden 6,7 im Plasmabereich 8 liegenden Entladungsweg fließen können, bildet sich im Plasmabereich 8 ein Plasma, durch das je nach der Zusammensetzung des Gases Strahlung 11 im UV-Bereich, insbesondere im VUV-Bereich, erzeugt wird. Diese Strahlung 11 regt die Leuchtstoffschicht 9 zum Leuchten an, die sichtbares Licht 13 in einer der drei Grundfarben emittiert, das durch die Frontplatte 1 nach außen tritt und somit einen leuchtenden Bildpunkt auf dem Bildschirm darstellt. In der Leuchtstoffschicht 9 kann beispielsweise als blau-emittierender Leuchtstoff BaMgAl10O17:Eu, als grün-emittierender Leuchtstoff beispielsweise Zn2SiO4:Mn und als rot-emittierender Leuchtstoff beispielsweise (Y,Gd)BO3:Eu verwendet werden.In the plasma cell, that is between the discharge electrodes 6, 7, each of which alternately acts as a cathode or anode, there is a gas, preferably a noble gas mixture of, for example, He, Ne or Kr, which is used as component Xe to generate UV light contains. After ignition of the surface discharge, as a result of which charges can flow on a discharge path lying between the discharge electrodes 6, 7 in the plasma region 8, a plasma is formed in the plasma region 8, through which, depending on the composition of the gas, radiation 11 in the UV region, in particular in the VUV region Area that is created. This radiation 11 stimulates the phosphor layer 9 to emit light, which emits visible light 13 in one of the three primary colors, which emerges through the front panel 1 and thus represents a luminous pixel on the screen. In the phosphor layer 9, BaMgAl 10 O 17 : Eu, for example, can be used as the blue-emitting phosphor, Zn 2 SiO 4 : Mn, for example, as the green-emitting phosphor and (Y, Gd) BO 3 : Eu as the red-emitting phosphor.

Die dielektrische Schicht 4 über den transparenten Entladungselektroden 6,7 dient unter anderem bei AC-Plasmabildschirmen dazu, eine direkte Entladung zwischen den aus leitfähigem Material bestehenden Entladungselektroden 6,7 und damit die Ausbildung eines Lichtbogens bei Zündung der Entladung zu unterbinden. The dielectric layer 4 over the transparent discharge electrodes 6,7 serves below other with AC plasma screens, a direct discharge between the conductive Material existing discharge electrodes 6.7 and thus the formation of a To prevent the arc from igniting the discharge.

Zur Herstellung einer Frontplatte 1 mit einer Schutzschicht 5 werden zunächst auf einer Glasplatte 3, deren Größe der gewünschten Bildschirmgröße entspricht, mittels Aufdampfverfahren und anschließender Strukturierung die Entladungselektroden 6,7 aufgebracht. Anschließend wird die dielektrische Schicht 4 aufgebracht und getrocknet.To produce a front panel 1 with a protective layer 5 are first on a Glass plate 3, the size of which corresponds to the desired screen size, by means of vapor deposition and subsequent structuring, the discharge electrodes 6, 7 are applied. The dielectric layer 4 is then applied and dried.

Zur Herstellung einer Schutzschicht 5 wird je nach Material ein unterschiedliches Verfahren, welche an sich bekannt sind, angewendet. Eine Schutzschicht 5, die kristallinen Diamant enthält, kann durch CVD-Methoden hergestellt. Dazu wird eine Gasmischung, die in der Regel Kohlenstoff und Wasserstoff sowie gegebenenfalls Sauerstoff, Edelgase oder Halogene enthält, in reaktive Radikale und Molekülbruchstücke zerlegt, aus denen sich auf einem heißen Substrat ein Diamantfilm abscheidet. Die Anregung der Gasmischung kann beispielsweise durch ein Plasma, einen heißen Draht, eine Bogenentladung oder eine chemische Flamme wie zum Beispiel eine Acetylen-Sauerstoff-Flamme.Depending on the material, a different method is used to produce a protective layer 5, which are known per se. A protective layer 5, the crystalline diamond contains, can be made by CVD methods. This is a gas mixture that usually carbon and hydrogen and optionally oxygen, noble gases or Halogens contains, broken down into reactive radicals and molecular fragments that make up deposits a diamond film on a hot substrate. The gas mixture can be excited for example by a plasma, a hot wire, an arc discharge or a chemical flame such as an acetylene-oxygen flame.

Eine Schutzschicht 5, welche AlN enthält, kann mittels reaktiven Sputtern aus einem Al-Target in einer stickstoffhaltigen Atmosphäre hergestellt werden. Eine Schutzschicht 5, welche AlN oder AlGaN enthält, kann auch mittels MO(metal organic)-CVD oder über Plasma CVD hergestellt werden. Hierbei werden entsprechende metall-organische Verbindungen entweder thermisch oder mit Hilfe eines Plasmas in Gegenwart einer Stickstoffquelle angeregt und umgesetzt.A protective layer 5, which contains AlN, can be made from an Al target by means of reactive sputtering be made in a nitrogenous atmosphere. A protective layer 5, which contains AlN or AlGaN can also by means of MO (metal organic) CVD or via Plasma CVD can be produced. Appropriate metal-organic compounds either thermally or using a plasma in the presence of a nitrogen source stimulated and implemented.

Ebenso kann eine Schutzschicht 5, welche BN enthält, mittels CVD oder reaktiven Sputterns hergestellt werden. In diesem Fall werden geeignete bor-organische Verbin dungen eingesetzt. Außerdem können BN-haltige Schichten durch ionenstrahlgestützte Abscheidtechniken hergestellt werden. Das BN kann ein kubisches oder hexagonales Kristallgitter besitzen.Likewise, a protective layer 5, which contains BN, by means of CVD or reactive Sputtering are made. In this case, suitable boron-organic compounds applications. In addition, BN-containing layers can be supported by ion beam Separation techniques are manufactured. The BN can be cubic or hexagonal Have crystal lattices.

Eine Schutzschicht 5, welche tetrahedral amorphen Kohlenstoff (t-a:C) enthält, kann beispielsweise über eine gefilterte Bogenentladung aus Graphit oder auch mittels CVD-Techniken hergestellt werden.A protective layer 5, which contains tetrahedral amorphous carbon (t-a: C), can For example, using a filtered arc discharge made of graphite or using CVD techniques getting produced.

Die Schichtdicke der Schutzschicht 5 beträgt vorzugsweise zwischen 2 nm und 10 µm. Ganz besonders bevorzugt sind Schichtdicken zwischen 5 nm und 1 µm.The layer thickness of the protective layer 5 is preferably between 2 nm and 10 μm. Layer thicknesses between 5 nm and 1 μm are very particularly preferred.

Die gesamte Frontplatte 1 wird zwei Stunden bei 100 bis 600 °C nachbehandelt und zusammen mit einer Trägerplatte 2 aus Glas, welche eine Rippenstruktur 12, leitfähige Adresselektroden 10 und eine Leuchtstoffschicht 9 aufweist, sowie einem Gas zum Bau eines AC-Plasmabildschirms verwendet. Das Gas enthält vorzugsweise ein Edelgasgemisch wie Ne/Xe, He/Xe oder Ne/He/Xe, wobei der Anteil von Xenon im Gas bevorzugt mindestens 7 Vol.-% beträgt. Das Gas kann auch reines Xenon enthalten. Je höher der Gehalt an UV-Licht generierendem Xenon ist, desto effizienter ist die UV-Lichtausbeute und damit die Anregung der Leuchtstoffe.The entire front panel 1 is aftertreated and treated at 100 to 600 ° C for two hours together with a carrier plate 2 made of glass, which has a rib structure 12, conductive Has address electrodes 10 and a phosphor layer 9, and a gas for construction of an AC plasma display. The gas preferably contains a noble gas mixture such as Ne / Xe, He / Xe or Ne / He / Xe, the proportion of xenon in the gas being preferred is at least 7% by volume. The gas can also contain pure xenon. The higher the The content of xenon that generates UV light, the more efficient the UV light yield and thus the excitation of the phosphors.

Die Schutzschicht 5, welche ein Material mit niedriger Elektronenaffinität enthält, erniedrigt die Zünd- und Betriebsspannungen des Plasmas. So kann der Effekt, dass mit steigendem Xenon-Gehalt die Zündspannung des Plasmas steigt teilweise kompensiert werden und es kann eine preiswerte Treiberelektronik im Plasmabildschirm eingesetzt werden. Der Plasmabildschirm weist dann neben einer resistenteren Schutzschicht 5 auch eine erhöhte Luminanz auf.The protective layer 5, which contains a material with low electron affinity, is lowered the ignition and operating voltages of the plasma. So the effect that with increasing Xenon content increases the ignition voltage of the plasma to be partially compensated and inexpensive driver electronics can be used in the plasma screen. The In addition to a more resistant protective layer 5, the plasma screen then also has an elevated one Luminance on.

Im folgenden werden Ausführungsformen der Erfindung erläutert, die beispielhafte Realisierungsmöglichkeiten darstellen.In the following, embodiments of the invention are explained, the exemplary implementation options represent.

Ausführungsbeispiel 1Embodiment 1

Mittels Mikrowellen-Plasma-CVD wurde als Schutzschicht 5 ein Diamantfilm auf die dielektrische Schicht 4 einer Frontplatte 1, welche eine Glasplatte 3, eine dielektrische Schicht 4 und zwei Entladungselektroden 6,7 aufweist, aufgebracht. Die dielektrische Schicht 4 enthielt PbO und die beiden Entladungselektroden 6,7 waren aus ITO. Die Schichtdicke der Schutzschicht 5 aus kristallinem Diamant betrug 0.5 µm.By means of microwave plasma CVD, a diamond film was applied to the protective layer 5 dielectric layer 4 of a front plate 1, which is a glass plate 3, a dielectric Layer 4 and two discharge electrodes 6.7, applied. The dielectric Layer 4 contained PbO and the two discharge electrodes 6, 7 were made of ITO. The Layer thickness of the protective layer 5 made of crystalline diamond was 0.5 μm.

Die gesamte Frontplatte 1 wurde zwei Stunden bei 200 bis 400 °C nachbehandelt und anschließend zusammen mit einer Trägerplatte 2 aus Glas, welche eine Rippenstruktur 12, Adresselektroden 10 aus Ag und eine Leuchtstoffschicht 9 aufweist, sowie einem Gasgemisch, welches eine Zusammensetzung von 7 Vol.-% Xe und 93 Vol.-% Ne aufwies, zum Bau eines AC-Plasmabildschirms verwendet, der erhöhte Luminanz aufwies.The entire front panel 1 was aftertreated and treated at 200 to 400 ° C for two hours then together with a carrier plate 2 made of glass, which has a rib structure 12, Has address electrodes 10 made of Ag and a phosphor layer 9, and a gas mixture, which had a composition of 7% by volume Xe and 93% by volume Ne, to Construction of an AC plasma display used, which had increased luminance.

Ausführungsbeispiel 2Embodiment 2

Mittels Mikrowellen-Plasma-CVD mit einem reinen Stickstoffplasma und Trimethylaluminium wurde als Schutzschicht 5 eine Schicht aus AlN auf die dielektrische Schicht 4 einer Frontplatte 1, welche eine Glasplatte 3, eine dielektrische Schicht 4 und zwei Entladungselektroden 6,7 aufweist, aufgebracht. Die dielektrische Schicht 4 enthielt PbO und die beiden Entladungselektroden 6,7 waren aus ITO. Die Schichtdicke der Schutzschicht 5 betrug 0.3 µm.Using microwave plasma CVD with a pure nitrogen plasma and trimethyl aluminum a layer of AlN was applied to the dielectric layer 4 as a protective layer 5 a front plate 1, which has a glass plate 3, a dielectric layer 4 and two discharge electrodes 6.7, applied. The dielectric layer 4 contained PbO and the two discharge electrodes 6, 7 were made of ITO. The layer thickness of the protective layer 5 was 0.3 µm.

Die gesamte Frontplatte 1 wurde zwei Stunden bei 200 bis 400 °C nachbehandelt und anschließend zusammen mit einer Trägerplatte 2 aus Glas, welche eine Rippenstruktur 12, Adresselektroden 10 aus Ag und eine Leuchtstoffschicht 9 aufweist, sowie einem Gasgemisch, welches eine Zusammensetzung von 20 Vol.-% Xe und 80 Vol.-% Ne aufwies, zum Bau eines Plasmabildschirms verwendet, der erhöhte Luminanz aufwies.The entire front panel 1 was aftertreated and treated at 200 to 400 ° C for two hours then together with a carrier plate 2 made of glass, which has a rib structure 12, Has address electrodes 10 made of Ag and a phosphor layer 9, and a gas mixture, which had a composition of 20% by volume Xe and 80% by volume Ne, to Construction of a plasma screen used, which had increased luminance.

Claims (2)

Plasmabildschirm ausgerüstet mit einer Frontplatte (1), die eine Glasplatte (3), auf der eine dielektrische Schicht (4) und eine Schutzschicht (5) aufgebracht sind, aufweist, mit einer Trägaplatte (2) ausgestattet mit einer Leuchtstoffschicht (9), mit einer Rippenstruktur (12), die den Raum zwischen Frontplatte (1) und Trägerplatte (2) in Plasmazellen, die mit einem Gas gefüllt sind, aufteilt, mit einem oder mehreren Elektroden-Arrays (6,7,10) auf der Frontplatte (1) und der Trägerplatte (2) zur Erzeugung von stillen elektrischen Entladungen in den Plasmazellen,
dadurch gekennzeichnet, dass die Schutzschicht (5) ein Material ausgewählt aus der Gruppe kristalliner Diamant, AlN, AlGaN, BN und tetrahedral amorpher Kohlenstoff enthält
Plasma screen equipped with a front plate (1), which has a glass plate (3) on which a dielectric layer (4) and a protective layer (5) are applied, with a carrier plate (2) equipped with a phosphor layer (9) a rib structure (12) which divides the space between the front plate (1) and carrier plate (2) into plasma cells which are filled with a gas, with one or more electrode arrays (6, 7, 10) on the front plate (1 ) and the support plate (2) for generating silent electrical discharges in the plasma cells,
characterized in that the protective layer (5) contains a material selected from the group consisting of crystalline diamond, AlN, AlGaN, BN and tetrahedral amorphous carbon
Plasmabildschirm nach Anspruch 1,
dadurch gekennzeichnet, dass das Gas Xenon in einem Anteil von über 7 Vol.-% enthält.
Plasma display according to claim 1,
characterized in that the gas contains xenon in a proportion of more than 7% by volume.
EP01000140A 2000-05-12 2001-05-09 Plasma display panel with protective layer Withdrawn EP1154456A3 (en)

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