US3710167A - Organic electroluminescent cells having a tunnel injection cathode - Google Patents

Organic electroluminescent cells having a tunnel injection cathode Download PDF

Info

Publication number
US3710167A
US3710167A US00051898A US3710167DA US3710167A US 3710167 A US3710167 A US 3710167A US 00051898 A US00051898 A US 00051898A US 3710167D A US3710167D A US 3710167DA US 3710167 A US3710167 A US 3710167A
Authority
US
United States
Prior art keywords
layer
phosphor
anode
cathode
anthracene
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
US00051898A
Inventor
J Dresner
A Goodman
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.)
RCA Corp
Original Assignee
RCA Corp
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 RCA Corp filed Critical RCA Corp
Application granted granted Critical
Publication of US3710167A publication Critical patent/US3710167A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B33/00—Electroluminescent light sources
    • H05B33/12—Light sources with substantially two-dimensional radiating surfaces
    • H05B33/22—Light sources with substantially two-dimensional radiating surfaces characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B33/00—Electroluminescent light sources
    • H05B33/12—Light sources with substantially two-dimensional radiating surfaces
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/80—Constructional details
    • H10K50/805—Electrodes
    • H10K50/82—Cathodes

Definitions

  • An electroluminescent cell comprises an anthracene layer having an anode and cathode thereon.
  • cathode of the novel cell is of the tunnel injection type.
  • a typical cathode consists of a 10-100 A. thick 14 Claims, 4 Drawing Figures ORGANIC ELECTROLUMINESCENT CELLS HAVING A TUNNEL INJECTION CATIIODE BACKGROUND OF THE INVENTIONO
  • This invention relates I to improved electroluminescent cells useful as simple light sources or in display devices. It more particularly relates to electroluminescent cells which employ organic phosphors as the luminescent material.
  • Organic phosphor electroluminescent cells are known in the art. These prior art cells are formed from admixtures of anthracene or other organic phosphor compositions with electrically conductive materials such as metals, graphite or other forms of carbon. The admixture is deposited as a thin layer on a conductive surface. The conductive surface is typically a tin oxide coating applied to a glass substrate. The admixture is coated with an insulating layer such as glycerin and a metal electrode is provided to make electrical contact with the glycerin. Examples of these prior art cells can be found with reference to U.S. Pat. No. 3,173,050 issued to E. F. Gurnee.
  • the electroluminescent cell In order to approach commercial utility the electroluminescent cell should have a long life, improved brightness, simple construction free of shorts and for many device applications, it should be compatible with silicon technology.
  • An electroluminescent cell comprises a layer of an organic phosphor composition, an anode upon one surface of the layer and a tunnel-injection type cathode upon the other surface of the layer.
  • FIG. 1 is a cross-sectional view of a novel electroluminescent cell.
  • FIG. 2 is a front elevational view of an embodiment of an electroluminescent cell having a desired luminescent pattern therein.
  • FIG. 3 is a cross-sectional view of the embodiment shown in FIG. 2 taken along line 33 thereof.
  • FIG. 4 is a cross-sectional view of an electroluminescent cell employing a glass support for the anode.
  • the organic phosphor layers utilized in the present invention comprise a conjugated organic compound of condensed benzene rings.
  • useful phosphors are anthracene, naphthalene, methyl derivatives of anthracene and anthracene doped with tetracene or other similar fluorescent dyes.
  • the phosphor should be of high purity.
  • a preferred phosphor is anthracene having an electron trap density in the order of 10 traps/cc.
  • the thickness of the phosphor layer should be less than l micrometers (um) and preferably between I and am.
  • the phosphor layer of the novel device is free of dispersed conductive particles. Such particles, if they were to exist in the novel device, would induce shorts and absorb light from the phosphor and thereby reduce the efficiency and life of the novel device.
  • the phosphor layer comprises phosphor grains which are mono-crystalline in the direction of current flow. This results in a more efficient cell.
  • a feature of the novel cells is the use of a tunnel injection cathode for injecting electrons into the phosphor.
  • a cathode comprises a base electrode material having a dielectric film of a thickness of less than about A., and generally between 10-100 A., on the surface thereof.
  • the dielectric film is in contact with the phosphor layer of the cell.
  • the dielectric material has a dielectric constant of less than.
  • a preferred tunnel injection cathode has as the electrode material a wafer of n type silicon, preferably degenerate n type silicon.
  • the dielectric film of this cathode is a l0-100 A. thick silicon dioxide layer on a surface of the silicon wafer.
  • This cathode is hereinafter designated as 11 type SiSiO
  • Another useful tunnel injection cathode consists of aluminum, such as an evaporated layer of aluminum, having a lO-lOO A. thick aluminum oxide layer thereon. This cathode is hereinafter designated as Al-Al O
  • Al-Al O The use of such cathodes results in devices which are easy to construct, are compatible with silicon technology, are long-lived and have improved brightness.
  • the anode of the device which is a hole injecting contact, may consist of a conductive oxide, such as tin oxide, indium oxide, or a mixture of cuprous oxide and cuprous iodide; a metal, such as gold or platinum; an alloy, such as selenium-tellurium alloy; or a tunnel inject ing contact such as p type silicon having a 10-100 A. thick layers of silicon dioxide thereon.
  • Preferred anodes comprise a transparent copper oxide and copper iodide layer or a conductive oxide such as tin oxide or indium oxide coated with a very thin transparent layer of Te. A Te layer which is a few atoms thick is sufficient.
  • anode or the cathode or both be transparent.
  • Examples of a transparent anode are films of tin oxide coated with a very thin layer of tellurium (preferably a few atoms thick) or tin oxide coated with a thin layer of a copper oxide-copper iodide mixture.
  • a transparent electrode can be obtained by forming it in a mesh-like configuration so that light is freely transmitted through the spaces in the mesh.
  • spacers defining this thickness may be employed.
  • the novel devices make possible the use of spacers which are an integral part of the electrode structure.
  • the silicon dioxide layer of the tunnel injecting cathode can be built up around the periphery of the electroluminescent cell so as to provide a spacer of several microns in thickness which is integral with the tunnel injection area (less than 100 A. thick) of the cell.
  • the cathode or anode may be formed on a glass support, either with or without a transparent conductive coating thereon, and the spacer evaporated, sputtered or otherwise formed on this structure.
  • the novel cell 4 comprises ananthracene layer 6 sandwiched between a cathode 8 and an anode 10.
  • the cathode comprises a degenerate n'type siliconwafer 12 having a silicon dioxide coating 14 thereon.
  • the degenerate silicon wafer typically has a resistivity in the range of 6X10 to lXlO'ohm-cm.
  • the silicon dioxide coating which may be formed by any of the techniques which are well known in the art, is provided with a thin central region 16 where electron injection occurs by a tunneling mechanism. This thin region is in the order of 10 to 100 A. thick and is preferably less than 50 A. thick.
  • the outer periphery 18 of the silicon dioxide layer is thicker than the central portion 16.
  • a preferred technique for forming the silicon dioxide coating for tunnel injection comprises the steps of (l) cleaning the silicon wafer in a boiling ammoniated solution of hydrogen peroxide, (2) etching the cleaned wafer in concentrated HF, (3) oxidizing the etched wafer in a steam atmosphere at 1,100 C., (4) recleaning and re-etching the oxidized wafer, (5) heating the wafer for several minutes at 150 C., (6) oxidizing the.
  • the anthracene layer 6 may be formed by melting finely divided anthracene on the central portion 16 of the silicon dioxide layer 14 and allowing this molten material to crystallize.
  • the anode 10 is provided on the anthracene layer 6 on the side opposite the cathode 8.
  • the anode 10 consists of a thin coating of a copper oxide-copper iodide film. This film may be deposited directly on the,
  • the copper oxide-copperiodide film is less than 100 A. thick. If the copper oxide-copper iodide film exceeds about 500 A. in thickness, the transmission of light therethrough is reduced such that it is preferably formed in a mesh or crossed-grid pattern so as to allow light to be efficiently emitted from the cell.
  • the silicon wafer 12 is connected to negative terminal of a battery and the copper oxidecopper iodide anode layer 10 is connected to the positive terminal of the battery. Electrons are injected into the anthracene layer 6 through the silicon dioxide layer 14 and holes are injected into the anthracene layer 6 from the copper oxide-copper iodide layer 10. Recombination of electron-hole pairs occurs in the anthracene layer 6 resulting in the emission of blue light.
  • the injecting tunnel cathode is shown to comprise n type silicon
  • p type silicon can also be used.
  • p type silicon has the advantage that it is easier to deposit p type silicon on glass than n type silicon
  • an electrolu-' minescent cell 30 comprises a grid-like anode 32.
  • a cathode structure 40 is positioned over the anthracene to form the complete cell.
  • This cathode structure 40 consists of a wafer 42 of n type silicon having a 2-3 pm thick SiO layer 44 thereon.
  • the SiO, layer 44 is in contact with the anthracene layer 38.
  • the SiO layer 44' has 1 mil. diameter plugs 46 of the 11 type silicon extending completely therethrough.
  • dielectric SiO, layer 48 is provided on the outer surface of each of the silicon plugs 46 so as to contact the anthracene layer 38.
  • the plugs are formed in a desired pattern, for example, to portray RCA as shown in FIG. 2. Electron injection into this device takes place by tunneling through the dielectric SiO, layer 48 on each of the silicon plugs 46.
  • An alternative and somewhat similar structure to that described with reference to FIGS. 2 and 3 is one in which the silicon dioxide layer 36 has an array of holes therein extending therethrough rather than silicon plugs extending through the SiO, layer as shown in the FIGURES.
  • the Si layer is provided with a thin SiO coating (IO- A.) in the region of each hole and the anthracene then fills each hole.
  • the cell 50 shown in FIG. 4 employs an AlAl O cathode structure 52.
  • the cathode may be formed by vacuum evaporating a layer 54 of aluminum onto a glass substrate 56 and anodizing the surface of the aluminum layer 54 to form an A1 0 layer 58 which is preferably from 10-50 A. thick.
  • the cell 50 is also provided with an anode 60 having spacers 62 the same as that described with reference to FIG. 3.
  • An organic phosphor layer 64 is disposed between and in contact with the anode and cathode.
  • the cathode can be formed in a thin line or mesh pattern.
  • a pattern can be formed,.for example, by evaporating the cathode material onto a glass substrate by standard flash evaporation or electron beam evaporation techniques through an appropriate mask.
  • tunnel injection cathodes comprising Al-Al O and SiSiO it should be understood that other metal-metal oxide tunnelinjection cathodes may also be useful, for example, tantalum-tantalum oxide and magnesium-magnesium oxide.
  • Electroluminescent cells made in accordance with the invention comprising anthracene containing tetracene therein in an amount not exceeding 5 ppm were operated at applied average fields of only approximately 2X10 volts/cm. across the phosphor layer. Light emission was observed at wavelengths between 4,l00-5,400 A. These cells comprised a cathode consisting of a fine grid of aluminum having about a 50 A.
  • anode consisting of either colloidal platinum paste, copper-copper iodide paste, silver-silver iodide paste, an evaporated conductive selenium-tellurium alloy or a conductive arsenic-tellurium alloy containing a small percentage of selenium therein.
  • the choice of anode did not have a major effect on the efficiency of light emission from the cell but it does affect the speed of response to the applied field.
  • current densities ranging from 5X10 to 5X10 amp/cm have been observed. The higher current densities correspond to measured surface brightnesses of 60 footlam berts. This may be compared to a brightness of only 10 foot-lamberts for the blue light of a commercial color television kinescope.
  • the quantum efficiency of these cells is between about 0.01-0.04 photons/electron.
  • Cells having a cathode consisting of n silicon, either as a wafer or a vacuum deposited film, covered with a 20-40 A. thick film of SiO and an evaporated transparent Cu O-Cul anode were also operated at an average field of about 2.5Xl volts/cm. These cells had a current density of l.8 l0' amp./cm. and a quantum efficiency of from about 0.01-0.03 photons/electron. The surface brightness of these cells was estimated to exceed foot-lamberts.
  • An electroluminescent cell comprising 1. a cathode structure consisting of a base of an electrode material selected from the group consisting of silicon and aluminum and having a thick dielectric insulating layer on one surface thereof, said dielectric layer being an oxide of said electrode material, said electrode material extending through said oxide layer to the surface thereof to form a plurality of plug-like protrusions in a predetermined pattern through said oxide layer, and a thin oxide tunnel injection layer over the exposed surfaces of said plug-like protrusions, said oxide being an oxide ofsaid electrode material,
  • organic phosphor composition comprises an organic compound having conjugated condensed benzene rings selected from the group consisting of anthracene, naphthalene, methyl derivatives of anthracene and anthracene doped with a fluorescent dye.
  • said anode comprises a member selected from the group consisting of a tin oxide, indium oxide, a mixture of cuprous oxide and cuprous iodide, gold, platinum, a selenium-tellurium alloy and p type silicon having a l0-100 A. thick layer of silicon dioxide thereon.
  • said anode comprises a transparent film selected from a member of the group consisting of a mixture of copper oxide and copper iodide, tin oxide and indium oxide, said film having a transparent film of tellurium thereover, said tellurium film being no more than several atomic layers thick.
  • a cell according to claim 12 wherein said peripheral dielectric thickness is from 1 to 10 micrometers.
  • An electroluminescent devise comprising:
  • a cathode structure consisting of a. n type silicon having a thick silicon dioxide dielectric insulating layer on one surface thereof, said silicon extending through said silicon dioxide layer to the surface thereof to form a plurality of plug-like protrusions in a predetermined pattern through said silicon dioxide,

Landscapes

  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Electroluminescent Light Sources (AREA)

Abstract

An electroluminescent cell comprises an anthracene layer having an anode and cathode thereon. The cathode of the novel cell is of the tunnel injection type. A typical cathode consists of a 10-100 A. thick layer of silicon dioxide deposited over a degenerate n type silicon body. The silicon dioxide layer of the cathode is placed in contact with the anthracence layer. The anode should provide hole injection into the anthracence layer. A preferred anode is a film of copper oxide and copper iodide.

Description

Dresner et a1.
[ 1 Jan. 9, 1973 ORGANIC ELEC'IROLIJMINESCENT CELLS HAVING A TUNNEL INJECTION CATHODE [75] Inventors: Josepli Dresner; Alvin Malcolm Goodman, both of Princeton, NJ.
[73] Assignee: RCA Corporation [22] Filed: July 2, 1970 [21] Appl. No.: 51,898
[52] US. Cl. ..313/l08 A, 313/1095 [51] Int. Cl. n qsggg gz [5 8] Field ofSearch "313/108 A, 109.5 108 D, Y 108 R 561 netei rice ii'i'id' M 0 UNITED STATES PATENTS 3,172,862 3/1965 Gurnee et al. 313/108 AX 3,359,445 12/1967 Roth ..313/l08 A 3,267,317 '8/1966 Fischer.... ..313/l08 D 3,382,394 5/1968 Mehl ..313/l08 5/1960 Fischer ..313/l08 2,938,136 3,116,427 12/1963 Giaever ..3l3/l08 D UX 3,530,325 9/1970 M'ehl ..3 13/108 OTHER PUBLICATIONS. Semiconductor Compounds, by A. Coblenz, Electronics Buyers Guide, June, 1958, R-4, R-5.
Primary Examiner-Palmer C. Demeo Attorney-Glenn H. Bruestle [57] ABSTRACT An electroluminescent cell comprises an anthracene layer having an anode and cathode thereon. The
cathode of the novel cell is of the tunnel injection type. A typical cathode consists of a 10-100 A. thick 14 Claims, 4 Drawing Figures ORGANIC ELECTROLUMINESCENT CELLS HAVING A TUNNEL INJECTION CATIIODE BACKGROUND OF THE INVENTIONO This invention relates I to improved electroluminescent cells useful as simple light sources or in display devices. It more particularly relates to electroluminescent cells which employ organic phosphors as the luminescent material.
Organic phosphor electroluminescent cells are known in the art. These prior art cells are formed from admixtures of anthracene or other organic phosphor compositions with electrically conductive materials such as metals, graphite or other forms of carbon. The admixture is deposited as a thin layer on a conductive surface. The conductive surface is typically a tin oxide coating applied to a glass substrate. The admixture is coated with an insulating layer such as glycerin and a metal electrode is provided to make electrical contact with the glycerin. Examples of these prior art cells can be found with reference to U.S. Pat. No. 3,173,050 issued to E. F. Gurnee.
Although the voltage and frequency requirements for operating the cells as described above are stated therein to offer an improvement in the then existing art, this improvement has not been sufficient to result in low cost, low voltage cells emitting a brightness which would approach commercial utility.
In order to approach commercial utility the electroluminescent cell should have a long life, improved brightness, simple construction free of shorts and for many device applications, it should be compatible with silicon technology.
SUMMARY OF THE INVENTION An electroluminescent cell comprises a layer of an organic phosphor composition, an anode upon one surface of the layer and a tunnel-injection type cathode upon the other surface of the layer.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a novel electroluminescent cell.
FIG. 2 is a front elevational view of an embodiment of an electroluminescent cell having a desired luminescent pattern therein.
FIG. 3 is a cross-sectional view of the embodiment shown in FIG. 2 taken along line 33 thereof.
FIG. 4 is a cross-sectional view of an electroluminescent cell employing a glass support for the anode.
DETAILED DESCRIPTION OF THE INVENTION The organic phosphor layers utilized in the present invention comprise a conjugated organic compound of condensed benzene rings. Examples of useful phosphors are anthracene, naphthalene, methyl derivatives of anthracene and anthracene doped with tetracene or other similar fluorescent dyes.
Preferably, the phosphor should be of high purity. For example, a preferred phosphor is anthracene having an electron trap density in the order of 10 traps/cc. The thickness of the phosphor layer should be less than l micrometers (um) and preferably between I and am.
Unlike the cited prior art devices of Gurnee, the phosphor layer of the novel device is free of dispersed conductive particles. Such particles, if they were to exist in the novel device, would induce shorts and absorb light from the phosphor and thereby reduce the efficiency and life of the novel device.
Preferably, the phosphor layer comprises phosphor grains which are mono-crystalline in the direction of current flow. This results in a more efficient cell.
A feature of the novel cells is the use of a tunnel injection cathode for injecting electrons into the phosphor. Such a cathode comprises a base electrode material having a dielectric film of a thickness of less than about A., and generally between 10-100 A., on the surface thereof. The dielectric film is in contact with the phosphor layer of the cell. Preferably the dielectric material has a dielectric constant of less than.
5, but higher dielectric constant films are also suitable.
A preferred tunnel injection cathode has as the electrode material a wafer of n type silicon, preferably degenerate n type silicon. The dielectric film of this cathode is a l0-100 A. thick silicon dioxide layer on a surface of the silicon wafer. This cathode is hereinafter designated as 11 type SiSiO Another useful tunnel injection cathode consists of aluminum, such as an evaporated layer of aluminum, having a lO-lOO A. thick aluminum oxide layer thereon. This cathode is hereinafter designated as Al-Al O The use of such cathodes results in devices which are easy to construct, are compatible with silicon technology, are long-lived and have improved brightness.
The anode of the device, which is a hole injecting contact, may consist of a conductive oxide, such as tin oxide, indium oxide, or a mixture of cuprous oxide and cuprous iodide; a metal, such as gold or platinum; an alloy, such as selenium-tellurium alloy; or a tunnel inject ing contact such as p type silicon having a 10-100 A. thick layers of silicon dioxide thereon. Preferred anodes comprise a transparent copper oxide and copper iodide layer or a conductive oxide such as tin oxide or indium oxide coated with a very thin transparent layer of Te. A Te layer which is a few atoms thick is sufficient.
Although edge emission is possible, for most purposes and in order for the device to emit a greater amount of light, it is preferred that either the anode or the cathode or both be transparent.
Examples of a transparent anode are films of tin oxide coated with a very thin layer of tellurium (preferably a few atoms thick) or tin oxide coated with a thin layer of a copper oxide-copper iodide mixture. A transparent electrode can be obtained by forming it in a mesh-like configuration so that light is freely transmitted through the spaces in the mesh.
In order to control the thickness of the phosphor layer, spacers defining this thickness may be employed. The novel devices make possible the use of spacers which are an integral part of the electrode structure. For example, the silicon dioxide layer of the tunnel injecting cathode can be built up around the periphery of the electroluminescent cell so as to provide a spacer of several microns in thickness which is integral with the tunnel injection area (less than 100 A. thick) of the cell.
Alternatively, the cathode or anode may be formed on a glass support, either with or withouta transparent conductive coating thereon, and the spacer evaporated, sputtered or otherwise formed on this structure.
Referring now to FIG. 1 there is shown a preferred novel electroluminescent cell 4. The novel cell 4 comprises ananthracene layer 6 sandwiched between a cathode 8 and an anode 10. The cathode comprises a degenerate n'type siliconwafer 12 having a silicon dioxide coating 14 thereon. The degenerate silicon wafer typically has a resistivity in the range of 6X10 to lXlO'ohm-cm. The silicon dioxide coating, which may be formed by any of the techniques which are well known in the art, is provided with a thin central region 16 where electron injection occurs by a tunneling mechanism. This thin region is in the order of 10 to 100 A. thick and is preferably less than 50 A. thick. The outer periphery 18 of the silicon dioxide layer is thicker than the central portion 16. This outer periphery 18, which has a typical uniform thickness of from 1 to pm., functions as a spacer to determine the thickness of the anthracene phosphor layer 6 of the cell and to prevent shorts. A preferred technique for forming the silicon dioxide coating for tunnel injection comprises the steps of (l) cleaning the silicon wafer in a boiling ammoniated solution of hydrogen peroxide, (2) etching the cleaned wafer in concentrated HF, (3) oxidizing the etched wafer in a steam atmosphere at 1,100 C., (4) recleaning and re-etching the oxidized wafer, (5) heating the wafer for several minutes at 150 C., (6) oxidizing the. wafer with water vapor at 600 C., and (7) annealing the oxidized wafer at 500 C. in a pure hydrogen atmosphere. This technique is the subject of a U.S. Patent Application filed by Alvin M. Goodman and James M. Breece.
The anthracene layer 6 may be formed by melting finely divided anthracene on the central portion 16 of the silicon dioxide layer 14 and allowing this molten material to crystallize.
j The anode 10, is provided on the anthracene layer 6 on the side opposite the cathode 8. The anode 10 consists of a thin coating of a copper oxide-copper iodide film. This film may be deposited directly on the,
anthracene or alternatively it is deposited on one surface of a conducting glass flat as shown. The copper oxide-copperiodide film is less than 100 A. thick. If the copper oxide-copper iodide film exceeds about 500 A. in thickness, the transmission of light therethrough is reduced such that it is preferably formed in a mesh or crossed-grid pattern so as to allow light to be efficiently emitted from the cell.
In operation, the silicon wafer 12 is connected to negative terminal of a battery and the copper oxidecopper iodide anode layer 10 is connected to the positive terminal of the battery. Electrons are injected into the anthracene layer 6 through the silicon dioxide layer 14 and holes are injected into the anthracene layer 6 from the copper oxide-copper iodide layer 10. Recombination of electron-hole pairs occurs in the anthracene layer 6 resulting in the emission of blue light.
Although the injecting tunnel cathode is shown to comprise n type silicon, p type silicon can also be used. In fact, p type silicon has the advantage that it is easier to deposit p type silicon on glass than n type silicon,
of the invention. In this embodiment, an electrolu-' minescent cell 30 comprises a grid-like anode 32.
formed on a transparent glass support 34, and a silicon dioxide spacer 36 around the periphery of theanode support 34. A 2-3 pm layer 38 of anthracene phosphor is disposed on the anode 32. A cathode structure 40 is positioned over the anthracene to form the complete cell. This cathode structure 40 consists of a wafer 42 of n type silicon having a 2-3 pm thick SiO layer 44 thereon. The SiO, layer 44 is in contact with the anthracene layer 38. The SiO layer 44'has 1 mil. diameter plugs 46 of the 11 type silicon extending completely therethrough. A 10-50 A. thick dielectric SiO, layer 48 is provided on the outer surface of each of the silicon plugs 46 so as to contact the anthracene layer 38. The plugs are formed in a desired pattern, for example, to portray RCA as shown in FIG. 2. Electron injection into this device takes place by tunneling through the dielectric SiO, layer 48 on each of the silicon plugs 46. An alternative and somewhat similar structure to that described with reference to FIGS. 2 and 3 is one in which the silicon dioxide layer 36 has an array of holes therein extending therethrough rather than silicon plugs extending through the SiO, layer as shown in the FIGURES. In this alternative structure, the Si layer is provided with a thin SiO coating (IO- A.) in the region of each hole and the anthracene then fills each hole.
The cell 50 shown in FIG. 4 employs an AlAl O cathode structure 52. The cathode may be formed by vacuum evaporating a layer 54 of aluminum onto a glass substrate 56 and anodizing the surface of the aluminum layer 54 to form an A1 0 layer 58 which is preferably from 10-50 A. thick. The cell 50 is also provided with an anode 60 having spacers 62 the same as that described with reference to FIG. 3. An organic phosphor layer 64 is disposed between and in contact with the anode and cathode.
-Where one desires light emission from the cathode side of the cell, the cathode can be formed in a thin line or mesh pattern. Such a pattern can be formed,.for example, by evaporating the cathode material onto a glass substrate by standard flash evaporation or electron beam evaporation techniques through an appropriate mask.
Although the examples indicate tunnel injection cathodes comprising Al-Al O and SiSiO it should be understood that other metal-metal oxide tunnelinjection cathodes may also be useful, for example, tantalum-tantalum oxide and magnesium-magnesium oxide.
Electroluminescent cells made in accordance with the invention comprising anthracene containing tetracene therein in an amount not exceeding 5 ppm were operated at applied average fields of only approximately 2X10 volts/cm. across the phosphor layer. Light emission was observed at wavelengths between 4,l00-5,400 A. These cells comprised a cathode consisting of a fine grid of aluminum having about a 50 A.
thick film of Al O thereover and an anode consisting of either colloidal platinum paste, copper-copper iodide paste, silver-silver iodide paste, an evaporated conductive selenium-tellurium alloy or a conductive arsenic-tellurium alloy containing a small percentage of selenium therein. The choice of anode did not have a major effect on the efficiency of light emission from the cell but it does affect the speed of response to the applied field. For the applied fields stated above, current densities ranging from 5X10 to 5X10 amp/cm have been observed. The higher current densities correspond to measured surface brightnesses of 60 footlam berts. This may be compared to a brightness of only 10 foot-lamberts for the blue light of a commercial color television kinescope. The quantum efficiency of these cells is between about 0.01-0.04 photons/electron.
Cells having a cathode consisting of n silicon, either as a wafer or a vacuum deposited film, covered with a 20-40 A. thick film of SiO and an evaporated transparent Cu O-Cul anode were also operated at an average field of about 2.5Xl volts/cm. These cells had a current density of l.8 l0' amp./cm. and a quantum efficiency of from about 0.01-0.03 photons/electron. The surface brightness of these cells was estimated to exceed foot-lamberts.
What is claimed is:
1. An electroluminescent cell comprising 1. a cathode structure consisting ofa base of an electrode material selected from the group consisting of silicon and aluminum and having a thick dielectric insulating layer on one surface thereof, said dielectric layer being an oxide of said electrode material, said electrode material extending through said oxide layer to the surface thereof to form a plurality of plug-like protrusions in a predetermined pattern through said oxide layer, and a thin oxide tunnel injection layer over the exposed surfaces of said plug-like protrusions, said oxide being an oxide ofsaid electrode material,
2. a layer of an organic phosphor over and in contact with said tunnel injection layer, and
3. a light transmitting anode structure over and in contact with said phosphor layer and spaced from said cathode structure.
2. The electroluminescent cell recited in claim 1 wherein said organic phosphor composition comprises an organic compound having conjugated condensed benzene rings selected from the group consisting of anthracene, naphthalene, methyl derivatives of anthracene and anthracene doped with a fluorescent dye.
3. The electroluminescent cell recited in claim 1 wherein said organic phosphor has an electron trap density in the order of IO traps/cc. or less.
4. The electroluminescent cell recited in claim 1 wherein said phosphor layer consists of phosphor grains which are monocrystalline in the direction of current flow.
5. The electroluminescent cell recited in claim I wherein said dielectric has dielectric constant of less than 5.
6. The electroluminescent cell recited in claim 1 wherein said electrode material is n-type degenerate silicon and wherein said dielectric layer is SiO having a thickness of from 10-100 A. I
7. The electroluminescent cell recited [I] claim 1 wherein said anode comprises a member selected from the group consisting of a tin oxide, indium oxide, a mixture of cuprous oxide and cuprous iodide, gold, platinum, a selenium-tellurium alloy and p type silicon having a l0-100 A. thick layer of silicon dioxide thereon.
8. The electroluminescent cell recited in claim 1 wherein said anode comprises a transparent film selected from a member of the group consisting of a mixture of copper oxide and copper iodide, tin oxide and indium oxide, said film having a transparent film of tellurium thereover, said tellurium film being no more than several atomic layers thick.
9. The electroluminescent cell recited in claim 1 wherein said anode has a mesh-like configuration.
10. A cell according to claim 1 wherein said phosphor layer is less than 10 micrometers in thickness.
11. A cell according to claim 1 wherein said phosphor layer contains anthracene.
12. A cell according to claim 1 wherein said cathode is spaced from said anode by an additional thickness of the dielectric layer around the periphery of said cell, which thickness defines the thickness of said phosphor layer.
13. A cell according to claim 12 wherein said peripheral dielectric thickness is from 1 to 10 micrometers.
14. An electroluminescent devise comprising:
1. a cathode structure consisting of a. n type silicon having a thick silicon dioxide dielectric insulating layer on one surface thereof, said silicon extending through said silicon dioxide layer to the surface thereof to form a plurality of plug-like protrusions in a predetermined pattern through said silicon dioxide,
b. a thin silicon dioxide tunnel injection layer over the exposed surfaces of said plug-like protrusions,
2. a layer of an organic phosphor over said tunnel-injection layer and,
3. a light transmitting anode structure over and in contact with said phosphor layer and spaced from said cathode structure.

Claims (17)

  1. 2. The electroluminescent cell recited in claim 1 wherein said organic phosphor composition comprises an organic compound having conjugated condensed benzene rings selected from the group consisting of anthracene, naphthalene, methyl derivatives of anthracene and anthracene doped with a fluorescent dye.
  2. 2. a layer of an organic phosphor over and in contact with said tunnel injection layer, and
  3. 2. a layer of an organic phosphor over said tunnel-injection layer and,
  4. 3. a light transmitting anode strucTure over and in contact with said phosphor layer and spaced from said cathode structure.
  5. 3. a light transmitting anode structure over and in contact with said phosphor layer and spaced from said cathode structure.
  6. 3. The electroluminescent cell recited in claim 1 wherein said organic phosphor has an electron trap density in the order of 1014 traps/cc. or less.
  7. 4. The electroluminescent cell recited in claim 1 wherein said phosphor layer consists of phosphor grains which are monocrystalline in the direction of current flow.
  8. 5. The electroluminescent cell recited in claim 1 wherein said dielectric has dielectric constant of less than 5.
  9. 6. The electroluminescent cell recited in claim 1 wherein said electrode material is n-type degenerate silicon and wherein said dielectric layer is SiO2 having a thickness of from 10-100 A.
  10. 7. The electroluminescent cell recited in claim 1 wherein said anode comprises a member selected from the group consisting of a tin oxide, indium oxide, a mixture of cuprous oxide and cuprous iodide, gold, platinum, a selenium-tellurium alloy and p type silicon having a 10-100 A. thick layer of silicon dioxide thereon.
  11. 8. The electroluminescent cell recited in claim 1 wherein said anode comprises a transparent film selected from a member of the group consisting of a mixture of copper oxide and copper iodide, tin oxide and indium oxide, said film having a transparent film of tellurium thereover, said tellurium film being no more than several atomic layers thick.
  12. 9. The electroluminescent cell recited in claim 1 wherein said anode has a mesh-like configuration.
  13. 10. A cell according to claim 1 wherein said phosphor layer is less than 10 micrometers in thickness.
  14. 11. A cell according to claim 1 wherein said phosphor layer contains anthracene.
  15. 12. A cell according to claim 1 wherein said cathode is spaced from said anode by an additional thickness of the dielectric layer around the periphery of said cell, which thickness defines the thickness of said phosphor layer.
  16. 13. A cell according to claim 12 wherein said peripheral dielectric thickness is from 1 to 10 micrometers.
  17. 14. An electroluminescent devise comprising:
US00051898A 1970-07-02 1970-07-02 Organic electroluminescent cells having a tunnel injection cathode Expired - Lifetime US3710167A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US5189870A 1970-07-02 1970-07-02

Publications (1)

Publication Number Publication Date
US3710167A true US3710167A (en) 1973-01-09

Family

ID=21974041

Family Applications (1)

Application Number Title Priority Date Filing Date
US00051898A Expired - Lifetime US3710167A (en) 1970-07-02 1970-07-02 Organic electroluminescent cells having a tunnel injection cathode

Country Status (1)

Country Link
US (1) US3710167A (en)

Cited By (91)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0044686A1 (en) * 1980-07-17 1982-01-27 EASTMAN KODAK COMPANY (a New Jersey corporation) Organic electroluminescent cell, process for manufacturing the cell and its use
US4720432A (en) * 1987-02-11 1988-01-19 Eastman Kodak Company Electroluminescent device with organic luminescent medium
US4725513A (en) * 1984-07-31 1988-02-16 Canon Kabushiki Kaisha Electroluminescent device
US4734338A (en) * 1984-07-31 1988-03-29 Canon Kabushiki Kaisha Electroluminescent device
US4741976A (en) * 1984-07-31 1988-05-03 Canon Kabushiki Kaisha Electroluminescent device
US4769292A (en) * 1987-03-02 1988-09-06 Eastman Kodak Company Electroluminescent device with modified thin film luminescent zone
US4775820A (en) * 1984-07-31 1988-10-04 Canon Kabushiki Kaisha Multilayer electroluminescent device
US4885211A (en) * 1987-02-11 1989-12-05 Eastman Kodak Company Electroluminescent device with improved cathode
US4950950A (en) * 1989-05-18 1990-08-21 Eastman Kodak Company Electroluminescent device with silazane-containing luminescent zone
US5409783A (en) * 1994-02-24 1995-04-25 Eastman Kodak Company Red-emitting organic electroluminescent device
US5552678A (en) * 1994-09-23 1996-09-03 Eastman Kodak Company AC drive scheme for organic led
US5554450A (en) * 1995-03-08 1996-09-10 Eastman Kodak Company Organic electroluminescent devices with high thermal stability
EP0786925A2 (en) 1996-01-26 1997-07-30 Eastman Kodak Company White light-emitting electroluminescent devices
US5834100A (en) * 1996-06-25 1998-11-10 Northwestern University Organic light-emitting dioddes and methods for assembly and emission control
EP0903964A1 (en) 1997-09-18 1999-03-24 Eastman Kodak Company Organic electroluminescent device with inorganic electron transporting layer
US6020078A (en) * 1998-12-18 2000-02-01 Eastman Kodak Company Green organic electroluminescent devices
US6127004A (en) * 1999-01-29 2000-10-03 Eastman Kodak Company Forming an amorphous fluorocarbon layer in electroluminescent devices
US6278237B1 (en) 1997-09-22 2001-08-21 Emagin Corporation Laterally structured high resolution multicolor organic electroluminescence display device
US20010051487A1 (en) * 2000-04-26 2001-12-13 Yuichi Hashimoto Method for making organic luminescent device
US6351067B2 (en) 1999-01-21 2002-02-26 City University Of Hong Kong Organic electroluminescent device with improved hole injecting structure
US6361886B2 (en) 1998-12-09 2002-03-26 Eastman Kodak Company Electroluminescent device with improved hole transport layer
US6399221B1 (en) 1996-06-25 2002-06-04 Northwestern University Organic light-emitting diodes and methods for assembly and emission control
US6465115B2 (en) 1998-12-09 2002-10-15 Eastman Kodak Company Electroluminescent device with anthracene derivatives hole transport layer
US20030015691A1 (en) * 2001-02-16 2003-01-23 Elecon, Incorporated Compositions produced by solvent exchange methods and articles of manufacture comprising same
US6517957B1 (en) 1997-05-19 2003-02-11 Canon Kabushiki Kaisha Organic compound and electroluminescent device using the same
US6534198B1 (en) 1997-05-19 2003-03-18 Canon Kabushiki Kaisha Silicon compound, method for making the same, and electroluminescent device using the same
US6583557B2 (en) 2000-04-26 2003-06-24 Canon Kabushiki Kaisha Organic luminescent element
US6586119B1 (en) 1997-05-19 2003-07-01 Canon Kabushiki Kaisha Luminescent device
US6596415B2 (en) 1998-12-09 2003-07-22 Eastman Kodak Company Electroluminescent device with polyphenyl hydrocarbon hole transport layer
US20030162053A1 (en) * 1996-06-25 2003-08-28 Marks Tobin J. Organic light - emitting diodes and methods for assembly and enhanced charge injection
US6632545B1 (en) 1999-02-23 2003-10-14 Junji Kido Electroluminescent element
US6632544B1 (en) 1999-02-23 2003-10-14 Junji Kido Aromatic amine derivative, soluble conductive compound, and electroluminscent element
US6636001B2 (en) 2001-01-09 2003-10-21 Canon Kabushiki Kaisha Organic electronic device and nonlinear device
US20030207153A1 (en) * 1998-04-28 2003-11-06 Canon Kabushiki Kaisha Luminescent device with a triarylamine compound
US6664731B2 (en) 2001-03-15 2003-12-16 Canon Kabushiki Kaisha Charge injection type light emitting device
US20040043140A1 (en) * 2002-08-21 2004-03-04 Ramesh Jagannathan Solid state lighting using compressed fluid coatings
US20040043138A1 (en) * 2002-08-21 2004-03-04 Ramesh Jagannathan Solid state lighting using compressed fluid coatings
US6717358B1 (en) 2002-10-09 2004-04-06 Eastman Kodak Company Cascaded organic electroluminescent devices with improved voltage stability
US20040092195A1 (en) * 1996-06-25 2004-05-13 Marks Tobin J. Organic light-emitting diodes and methods for assembly and emission control
US20040108510A1 (en) * 2002-12-06 2004-06-10 Eastman Kodak Company Compressed fluid formulation containing electron transporting material
US20040110866A1 (en) * 2002-12-06 2004-06-10 Eastman Kodak Company Compressed fluid formulation containing hole transporting material
US20040113542A1 (en) * 2002-12-11 2004-06-17 Applied Materials, Inc. Low temperature process for passivation applications
US20040135749A1 (en) * 2003-01-14 2004-07-15 Eastman Kodak Company Compensating for aging in OLED devices
US20040170861A1 (en) * 2003-02-28 2004-09-02 Eastman Kodak Company Organic light emitting diodes for production of polarized light
US20040183066A1 (en) * 2003-03-18 2004-09-23 Eastman Kodak Company P-type materials and mixtures for electronic devices
US20040185297A1 (en) * 2003-03-18 2004-09-23 Eastman Kodak Company Cascaded organic electroluminescent devices
US6821648B2 (en) 1999-12-02 2004-11-23 Junji Kido Electroluminescent element
US20040240198A1 (en) * 2003-05-28 2004-12-02 Van Laar Ronald Joseph Automated self-illuminating sports & safety helmet
US20050014018A1 (en) * 2003-07-10 2005-01-20 Eastman Kodak Company Organic electroluminescent devices with high luminance
US20050176230A1 (en) * 2004-02-06 2005-08-11 Eastman Kodak Company Providing fluorocarbon layers on conductive electrodes in making electronic devices such as OLED devices
US6949879B1 (en) * 1999-04-07 2005-09-27 Microemissive Displays Limited Optoelectronic display
US20060082289A1 (en) * 2004-10-15 2006-04-20 Industrial Technology Research Institute Cathode structure for inverted organic light emitting devices
US20060273713A1 (en) * 2005-06-02 2006-12-07 Eastman Kodak Company Process for making an organic light-emitting device
WO2006138075A2 (en) 2005-06-17 2006-12-28 Eastman Kodak Company Organic element for low voltage electroluminescent devices
WO2007050301A2 (en) 2005-10-26 2007-05-03 Eastman Kodak Company Organic element for low voltage electroluminescent devices
US20070122655A1 (en) * 2004-09-20 2007-05-31 Eastman Kodak Company Electroluminescent device with quinazoline complex emitter
US20070122657A1 (en) * 2005-11-30 2007-05-31 Eastman Kodak Company Electroluminescent device containing a phenanthroline derivative
US20070207345A1 (en) * 2006-03-01 2007-09-06 Eastman Kodak Company Electroluminescent device including gallium complexes
US20070252522A1 (en) * 2005-11-30 2007-11-01 Eastman Kodak Company Electroluminescent device including an anthracene derivative
WO2008010915A2 (en) 2006-07-18 2008-01-24 Eastman Kodak Company Light emitting device containing phosphorescent complex
US20080032123A1 (en) * 2006-08-02 2008-02-07 Spindler Jeffrey P Dual electron-transporting layer for oled device
US20080057183A1 (en) * 2006-08-31 2008-03-06 Spindler Jeffrey P Method for lithium deposition in oled device
US20080176099A1 (en) * 2007-01-18 2008-07-24 Hatwar Tukaram K White oled device with improved functions
US20080182129A1 (en) * 2007-01-30 2008-07-31 Klubek Kevin P Oleds having high efficiency and excellent lifetime
US20080284318A1 (en) * 2007-05-17 2008-11-20 Deaton Joseph C Hybrid fluorescent/phosphorescent oleds
US20080284317A1 (en) * 2007-05-17 2008-11-20 Liang-Sheng Liao Hybrid oled having improved efficiency
US20080315753A1 (en) * 2007-06-20 2008-12-25 Liang-Sheng Liao Phosphorescent oled having double exciton-blocking layers
US20090102356A1 (en) * 2007-10-17 2009-04-23 Technical Institute Of Physics And Chemistry Of Chinese Academy Of Sciences NOVEL ORGANIC COMPOUND HAVING ELECTRON-TRANSPORTING AND/OR HOLE-BLOCKING PERFORMANCE AND ITS USE AND OLEDs COMPRISING THE COMPOUND
US20090108736A1 (en) * 2007-10-26 2009-04-30 Begley William J Phosphorescent oled device with certain fluoranthene host
US20090108735A1 (en) * 2007-10-26 2009-04-30 Begley William J Oled device with fluoranthene electron transport materials
US20090110956A1 (en) * 2007-10-26 2009-04-30 Begley William J Oled device with electron transport material combination
US20090108734A1 (en) * 2007-10-26 2009-04-30 Begley William J Oled device with certain fluoranthene light-emitting dopants
US20090110957A1 (en) * 2007-10-26 2009-04-30 Begley William J Oled device with certain fluoranthene host
US20090115316A1 (en) * 2007-11-02 2009-05-07 Shiying Zheng Organic electroluminescent device having an azatriphenylene derivative
US20090159911A1 (en) * 2007-12-21 2009-06-25 Chi Mei Communication Systems, Inc. Light-emitting diode package and method for fabricating the same
US20090162612A1 (en) * 2007-12-19 2009-06-25 Hatwar Tukaram K Oled device having two electron-transport layers
US20090242877A1 (en) * 2008-03-25 2009-10-01 Eastman Kodak Company Oled device with hole-transport and electron-transport materials
US20090309487A1 (en) * 2008-06-12 2009-12-17 Royster Jr Tommie L Phosphorescent oled device with mixed hosts
US20100019671A1 (en) * 2005-10-26 2010-01-28 Eastman Kodak Company Organic element for low voltage electroluminescent devices
US20100052516A1 (en) * 2008-08-28 2010-03-04 Xiaofan Ren Emitting complex for electroluminescent devices
US20100084647A1 (en) * 2006-04-27 2010-04-08 Kondakova Marina E Electroluminescent devices including organic eil layer
US20100117520A1 (en) * 2008-11-12 2010-05-13 Begley William J Oled device with fluoranthene electron injection materials
US20100117519A1 (en) * 2008-11-07 2010-05-13 Begley William J Electroluminescent device containing a flouranthene compound
US20100141122A1 (en) * 2008-12-09 2010-06-10 Begley William J Oled device with cyclobutene electron injection materials
US20100207513A1 (en) * 2009-02-13 2010-08-19 Begley William J Oled with fluoranthene-macrocyclic materials
US20100219747A1 (en) * 2009-02-27 2010-09-02 Tutt Lee W Inverted bottom-emitting oled device
US20100219748A1 (en) * 2009-02-27 2010-09-02 Kondakova Marina E Oled device with stabilized green light-emitting layer
US20100244677A1 (en) * 2009-03-31 2010-09-30 Begley William J Oled device containing a silyl-fluoranthene derivative
US20100253210A1 (en) * 2009-04-06 2010-10-07 Vargas J Ramon Organic element for electroluminescent devices
US8900722B2 (en) 2007-11-29 2014-12-02 Global Oled Technology Llc OLED device employing alkali metal cluster compounds
DE102015114167A1 (en) * 2015-08-26 2017-03-02 Osram Oled Gmbh Light-emitting diode and method for producing a light-emitting diode

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2938136A (en) * 1958-08-26 1960-05-24 Gen Electric Electroluminescent lamp
US3116427A (en) * 1960-07-05 1963-12-31 Gen Electric Electron tunnel emission device utilizing an insulator between two conductors eitheror both of which may be superconductive
US3172862A (en) * 1960-09-29 1965-03-09 Dow Chemical Co Organic electroluminescent phosphors
US3267317A (en) * 1963-02-25 1966-08-16 Rca Corp Device for producing recombination radiation
US3359445A (en) * 1964-10-07 1967-12-19 Dow Chemical Co Electroluminescent cells
US3382394A (en) * 1965-03-24 1968-05-07 American Cyanamid Co Electroluminescent process including injection of negative carriers into a crystal of an organic compound
US3530325A (en) * 1967-08-21 1970-09-22 American Cyanamid Co Conversion of electrical energy into light

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2938136A (en) * 1958-08-26 1960-05-24 Gen Electric Electroluminescent lamp
US3116427A (en) * 1960-07-05 1963-12-31 Gen Electric Electron tunnel emission device utilizing an insulator between two conductors eitheror both of which may be superconductive
US3172862A (en) * 1960-09-29 1965-03-09 Dow Chemical Co Organic electroluminescent phosphors
US3267317A (en) * 1963-02-25 1966-08-16 Rca Corp Device for producing recombination radiation
US3359445A (en) * 1964-10-07 1967-12-19 Dow Chemical Co Electroluminescent cells
US3382394A (en) * 1965-03-24 1968-05-07 American Cyanamid Co Electroluminescent process including injection of negative carriers into a crystal of an organic compound
US3530325A (en) * 1967-08-21 1970-09-22 American Cyanamid Co Conversion of electrical energy into light

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Semiconductor Compounds, by A. Coblenz, Electronics Buyers Guide, June, 1958, R 4, R 5. *

Cited By (144)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0044686A1 (en) * 1980-07-17 1982-01-27 EASTMAN KODAK COMPANY (a New Jersey corporation) Organic electroluminescent cell, process for manufacturing the cell and its use
US4725513A (en) * 1984-07-31 1988-02-16 Canon Kabushiki Kaisha Electroluminescent device
US4734338A (en) * 1984-07-31 1988-03-29 Canon Kabushiki Kaisha Electroluminescent device
US4741976A (en) * 1984-07-31 1988-05-03 Canon Kabushiki Kaisha Electroluminescent device
US4775820A (en) * 1984-07-31 1988-10-04 Canon Kabushiki Kaisha Multilayer electroluminescent device
US4720432A (en) * 1987-02-11 1988-01-19 Eastman Kodak Company Electroluminescent device with organic luminescent medium
US4885211A (en) * 1987-02-11 1989-12-05 Eastman Kodak Company Electroluminescent device with improved cathode
US4769292A (en) * 1987-03-02 1988-09-06 Eastman Kodak Company Electroluminescent device with modified thin film luminescent zone
US4950950A (en) * 1989-05-18 1990-08-21 Eastman Kodak Company Electroluminescent device with silazane-containing luminescent zone
US5409783A (en) * 1994-02-24 1995-04-25 Eastman Kodak Company Red-emitting organic electroluminescent device
US5552678A (en) * 1994-09-23 1996-09-03 Eastman Kodak Company AC drive scheme for organic led
US5554450A (en) * 1995-03-08 1996-09-10 Eastman Kodak Company Organic electroluminescent devices with high thermal stability
EP0786925A2 (en) 1996-01-26 1997-07-30 Eastman Kodak Company White light-emitting electroluminescent devices
US5834100A (en) * 1996-06-25 1998-11-10 Northwestern University Organic light-emitting dioddes and methods for assembly and emission control
US6939625B2 (en) 1996-06-25 2005-09-06 Nôrthwestern University Organic light-emitting diodes and methods for assembly and enhanced charge injection
US7094121B2 (en) 1996-06-25 2006-08-22 Northwestern University Organic light-emitting diodes and methods for assembly and emission control
US20030162053A1 (en) * 1996-06-25 2003-08-28 Marks Tobin J. Organic light - emitting diodes and methods for assembly and enhanced charge injection
US8053094B2 (en) 1996-06-25 2011-11-08 Northwestern University Organic light-emitting diodes and methods for assembly and enhanced charge injection
US7969088B2 (en) 1996-06-25 2011-06-28 Northwestern University Method of using silicon molecular components for controlling charge migration and light emission of organic light-emitting diodes
US20090284137A1 (en) * 1996-06-25 2009-11-19 Northwestern University Organic light-emitting diodes and methods for assembly and emission control
US20040092195A1 (en) * 1996-06-25 2004-05-13 Marks Tobin J. Organic light-emitting diodes and methods for assembly and emission control
US6399221B1 (en) 1996-06-25 2002-06-04 Northwestern University Organic light-emitting diodes and methods for assembly and emission control
US20090284145A1 (en) * 1996-06-25 2009-11-19 Marks Tobin J Organic Light-Emitting Diodes and Methods for Assembly and Enhanced Charge Injection
US6586119B1 (en) 1997-05-19 2003-07-01 Canon Kabushiki Kaisha Luminescent device
US20030216591A1 (en) * 1997-05-19 2003-11-20 Kazunori Ueno Silicon compound and method for making the same
US6534198B1 (en) 1997-05-19 2003-03-18 Canon Kabushiki Kaisha Silicon compound, method for making the same, and electroluminescent device using the same
US7022867B2 (en) 1997-05-19 2006-04-04 Canon Kabushiki Kaisha Silicon compound and method for making the same
US6858325B2 (en) 1997-05-19 2005-02-22 Canon Kabushiki Kaisha Organic compound and electroluminescent device using the same
US6517957B1 (en) 1997-05-19 2003-02-11 Canon Kabushiki Kaisha Organic compound and electroluminescent device using the same
EP0903964A1 (en) 1997-09-18 1999-03-24 Eastman Kodak Company Organic electroluminescent device with inorganic electron transporting layer
US6278237B1 (en) 1997-09-22 2001-08-21 Emagin Corporation Laterally structured high resolution multicolor organic electroluminescence display device
US20050025997A1 (en) * 1998-04-28 2005-02-03 Canon Kabushiki Kaisha Luminescent device with a triarylamine compound
US6833200B2 (en) 1998-04-28 2004-12-21 Canon Kabushiki Kaisha Luminescent device with a triarylamine compound
US20030207153A1 (en) * 1998-04-28 2003-11-06 Canon Kabushiki Kaisha Luminescent device with a triarylamine compound
US6699595B2 (en) 1998-12-09 2004-03-02 Eastman Kodak Company Electroluminescent device with polyphenyl hydrocarbon hole transport layer
US6596415B2 (en) 1998-12-09 2003-07-22 Eastman Kodak Company Electroluminescent device with polyphenyl hydrocarbon hole transport layer
US6465115B2 (en) 1998-12-09 2002-10-15 Eastman Kodak Company Electroluminescent device with anthracene derivatives hole transport layer
US6361886B2 (en) 1998-12-09 2002-03-26 Eastman Kodak Company Electroluminescent device with improved hole transport layer
EP2270897A2 (en) 1998-12-09 2011-01-05 Global OLED Technology LLC Electroluminescent device with antracene derivatives hole transport layer
US6020078A (en) * 1998-12-18 2000-02-01 Eastman Kodak Company Green organic electroluminescent devices
US6351067B2 (en) 1999-01-21 2002-02-26 City University Of Hong Kong Organic electroluminescent device with improved hole injecting structure
US6127004A (en) * 1999-01-29 2000-10-03 Eastman Kodak Company Forming an amorphous fluorocarbon layer in electroluminescent devices
US6632545B1 (en) 1999-02-23 2003-10-14 Junji Kido Electroluminescent element
US6632544B1 (en) 1999-02-23 2003-10-14 Junji Kido Aromatic amine derivative, soluble conductive compound, and electroluminscent element
US6949879B1 (en) * 1999-04-07 2005-09-27 Microemissive Displays Limited Optoelectronic display
US6821648B2 (en) 1999-12-02 2004-11-23 Junji Kido Electroluminescent element
US20010051487A1 (en) * 2000-04-26 2001-12-13 Yuichi Hashimoto Method for making organic luminescent device
US6583557B2 (en) 2000-04-26 2003-06-24 Canon Kabushiki Kaisha Organic luminescent element
US6636001B2 (en) 2001-01-09 2003-10-21 Canon Kabushiki Kaisha Organic electronic device and nonlinear device
US20040258952A1 (en) * 2001-02-16 2004-12-23 Haghighat R. Ross Compositions produced by solvent exchange methods and uses thereof
US20040258951A1 (en) * 2001-02-16 2004-12-23 Haghighat R. Ross Compositions produced by solvent exchange methods and uses thereof
US20030015691A1 (en) * 2001-02-16 2003-01-23 Elecon, Incorporated Compositions produced by solvent exchange methods and articles of manufacture comprising same
US6852250B2 (en) 2001-02-16 2005-02-08 Elecon, Inc. Compositions produced by solvent exchange methods and articles of manufacture comprising same
US6664731B2 (en) 2001-03-15 2003-12-16 Canon Kabushiki Kaisha Charge injection type light emitting device
US20040043138A1 (en) * 2002-08-21 2004-03-04 Ramesh Jagannathan Solid state lighting using compressed fluid coatings
US20040043140A1 (en) * 2002-08-21 2004-03-04 Ramesh Jagannathan Solid state lighting using compressed fluid coatings
US6717358B1 (en) 2002-10-09 2004-04-06 Eastman Kodak Company Cascaded organic electroluminescent devices with improved voltage stability
US6896723B2 (en) 2002-12-06 2005-05-24 Eastman Kodak Company Compressed fluid formulation containing hole transporting material
US20040108510A1 (en) * 2002-12-06 2004-06-10 Eastman Kodak Company Compressed fluid formulation containing electron transporting material
US6927415B2 (en) 2002-12-06 2005-08-09 Eastman Kodak Company Compressed fluid formulation containing electron transporting material
US20040110866A1 (en) * 2002-12-06 2004-06-10 Eastman Kodak Company Compressed fluid formulation containing hole transporting material
US20040113542A1 (en) * 2002-12-11 2004-06-17 Applied Materials, Inc. Low temperature process for passivation applications
US7086918B2 (en) * 2002-12-11 2006-08-08 Applied Materials, Inc. Low temperature process for passivation applications
US7079091B2 (en) 2003-01-14 2006-07-18 Eastman Kodak Company Compensating for aging in OLED devices
US20040135749A1 (en) * 2003-01-14 2004-07-15 Eastman Kodak Company Compensating for aging in OLED devices
US20040170861A1 (en) * 2003-02-28 2004-09-02 Eastman Kodak Company Organic light emitting diodes for production of polarized light
US7037599B2 (en) 2003-02-28 2006-05-02 Eastman Kodak Company Organic light emitting diodes for production of polarized light
US6869699B2 (en) 2003-03-18 2005-03-22 Eastman Kodak Company P-type materials and mixtures for electronic devices
US20040185297A1 (en) * 2003-03-18 2004-09-23 Eastman Kodak Company Cascaded organic electroluminescent devices
US6991859B2 (en) 2003-03-18 2006-01-31 Eastman Kodak Company Cascaded organic electroluminescent devices
US20040183066A1 (en) * 2003-03-18 2004-09-23 Eastman Kodak Company P-type materials and mixtures for electronic devices
US20040240198A1 (en) * 2003-05-28 2004-12-02 Van Laar Ronald Joseph Automated self-illuminating sports & safety helmet
US20050014018A1 (en) * 2003-07-10 2005-01-20 Eastman Kodak Company Organic electroluminescent devices with high luminance
US6919140B2 (en) 2003-07-10 2005-07-19 Eastman Kodak Company Organic electroluminescent devices with high luminance
US7041608B2 (en) 2004-02-06 2006-05-09 Eastman Kodak Company Providing fluorocarbon layers on conductive electrodes in making electronic devices such as OLED devices
US20050176230A1 (en) * 2004-02-06 2005-08-11 Eastman Kodak Company Providing fluorocarbon layers on conductive electrodes in making electronic devices such as OLED devices
US9040170B2 (en) 2004-09-20 2015-05-26 Global Oled Technology Llc Electroluminescent device with quinazoline complex emitter
US20070122655A1 (en) * 2004-09-20 2007-05-31 Eastman Kodak Company Electroluminescent device with quinazoline complex emitter
US20060082289A1 (en) * 2004-10-15 2006-04-20 Industrial Technology Research Institute Cathode structure for inverted organic light emitting devices
US7307380B2 (en) * 2004-10-15 2007-12-11 Industrial Technology Research Institute Cathode structure for inverted organic light emitting devices
US20060273713A1 (en) * 2005-06-02 2006-12-07 Eastman Kodak Company Process for making an organic light-emitting device
WO2006138075A2 (en) 2005-06-17 2006-12-28 Eastman Kodak Company Organic element for low voltage electroluminescent devices
US8956738B2 (en) 2005-10-26 2015-02-17 Global Oled Technology Llc Organic element for low voltage electroluminescent devices
US20100019671A1 (en) * 2005-10-26 2010-01-28 Eastman Kodak Company Organic element for low voltage electroluminescent devices
WO2007050301A2 (en) 2005-10-26 2007-05-03 Eastman Kodak Company Organic element for low voltage electroluminescent devices
US20070252522A1 (en) * 2005-11-30 2007-11-01 Eastman Kodak Company Electroluminescent device including an anthracene derivative
US9666826B2 (en) 2005-11-30 2017-05-30 Global Oled Technology Llc Electroluminescent device including an anthracene derivative
US20070122657A1 (en) * 2005-11-30 2007-05-31 Eastman Kodak Company Electroluminescent device containing a phenanthroline derivative
US20070207345A1 (en) * 2006-03-01 2007-09-06 Eastman Kodak Company Electroluminescent device including gallium complexes
US9118020B2 (en) 2006-04-27 2015-08-25 Global Oled Technology Llc Electroluminescent devices including organic eil layer
US20100084647A1 (en) * 2006-04-27 2010-04-08 Kondakova Marina E Electroluminescent devices including organic eil layer
WO2008010915A2 (en) 2006-07-18 2008-01-24 Eastman Kodak Company Light emitting device containing phosphorescent complex
US20080032123A1 (en) * 2006-08-02 2008-02-07 Spindler Jeffrey P Dual electron-transporting layer for oled device
US20080057183A1 (en) * 2006-08-31 2008-03-06 Spindler Jeffrey P Method for lithium deposition in oled device
US20080176099A1 (en) * 2007-01-18 2008-07-24 Hatwar Tukaram K White oled device with improved functions
US20080182129A1 (en) * 2007-01-30 2008-07-31 Klubek Kevin P Oleds having high efficiency and excellent lifetime
US8795855B2 (en) 2007-01-30 2014-08-05 Global Oled Technology Llc OLEDs having high efficiency and excellent lifetime
US9620721B2 (en) 2007-01-30 2017-04-11 Global Oled Technology Llc OLEDs having high efficiency and excellent lifetime
US20080284317A1 (en) * 2007-05-17 2008-11-20 Liang-Sheng Liao Hybrid oled having improved efficiency
US20080284318A1 (en) * 2007-05-17 2008-11-20 Deaton Joseph C Hybrid fluorescent/phosphorescent oleds
US8034465B2 (en) 2007-06-20 2011-10-11 Global Oled Technology Llc Phosphorescent oled having double exciton-blocking layers
US20080315753A1 (en) * 2007-06-20 2008-12-25 Liang-Sheng Liao Phosphorescent oled having double exciton-blocking layers
US20090102356A1 (en) * 2007-10-17 2009-04-23 Technical Institute Of Physics And Chemistry Of Chinese Academy Of Sciences NOVEL ORGANIC COMPOUND HAVING ELECTRON-TRANSPORTING AND/OR HOLE-BLOCKING PERFORMANCE AND ITS USE AND OLEDs COMPRISING THE COMPOUND
US8101290B2 (en) 2007-10-17 2012-01-24 Technical Institute Of Physics And Chemistry Of Chinese Academy Of Sciences Organic compound having electron-transporting and/or hole-blocking performance and its use and OLEDs comprising the compound
US20090108735A1 (en) * 2007-10-26 2009-04-30 Begley William J Oled device with fluoranthene electron transport materials
US8129039B2 (en) 2007-10-26 2012-03-06 Global Oled Technology, Llc Phosphorescent OLED device with certain fluoranthene host
US20090108736A1 (en) * 2007-10-26 2009-04-30 Begley William J Phosphorescent oled device with certain fluoranthene host
US20090110956A1 (en) * 2007-10-26 2009-04-30 Begley William J Oled device with electron transport material combination
US8431242B2 (en) 2007-10-26 2013-04-30 Global Oled Technology, Llc. OLED device with certain fluoranthene host
US8420229B2 (en) 2007-10-26 2013-04-16 Global OLED Technologies LLC OLED device with certain fluoranthene light-emitting dopants
EP2568515A1 (en) 2007-10-26 2013-03-13 Global OLED Technology LLC OLED device with fluoranthene electron transport materials
US20090108734A1 (en) * 2007-10-26 2009-04-30 Begley William J Oled device with certain fluoranthene light-emitting dopants
US20090110957A1 (en) * 2007-10-26 2009-04-30 Begley William J Oled device with certain fluoranthene host
US8076009B2 (en) 2007-10-26 2011-12-13 Global Oled Technology, Llc. OLED device with fluoranthene electron transport materials
US20090115316A1 (en) * 2007-11-02 2009-05-07 Shiying Zheng Organic electroluminescent device having an azatriphenylene derivative
US7914908B2 (en) 2007-11-02 2011-03-29 Global Oled Technology Llc Organic electroluminescent device having an azatriphenylene derivative
US8900722B2 (en) 2007-11-29 2014-12-02 Global Oled Technology Llc OLED device employing alkali metal cluster compounds
US20090162612A1 (en) * 2007-12-19 2009-06-25 Hatwar Tukaram K Oled device having two electron-transport layers
US20090159911A1 (en) * 2007-12-21 2009-06-25 Chi Mei Communication Systems, Inc. Light-emitting diode package and method for fabricating the same
US7768026B2 (en) * 2007-12-21 2010-08-03 Chi Mei Communication Systems, Inc. Light-emitting diode package and method for fabricating the same
US20090242877A1 (en) * 2008-03-25 2009-10-01 Eastman Kodak Company Oled device with hole-transport and electron-transport materials
US7947974B2 (en) 2008-03-25 2011-05-24 Global Oled Technology Llc OLED device with hole-transport and electron-transport materials
US20090309487A1 (en) * 2008-06-12 2009-12-17 Royster Jr Tommie L Phosphorescent oled device with mixed hosts
US8324800B2 (en) 2008-06-12 2012-12-04 Global Oled Technology Llc Phosphorescent OLED device with mixed hosts
US8247088B2 (en) 2008-08-28 2012-08-21 Global Oled Technology Llc Emitting complex for electroluminescent devices
US20100052516A1 (en) * 2008-08-28 2010-03-04 Xiaofan Ren Emitting complex for electroluminescent devices
US7931975B2 (en) 2008-11-07 2011-04-26 Global Oled Technology Llc Electroluminescent device containing a flouranthene compound
US20100117519A1 (en) * 2008-11-07 2010-05-13 Begley William J Electroluminescent device containing a flouranthene compound
US8088500B2 (en) 2008-11-12 2012-01-03 Global Oled Technology Llc OLED device with fluoranthene electron injection materials
US20100117520A1 (en) * 2008-11-12 2010-05-13 Begley William J Oled device with fluoranthene electron injection materials
US20100141122A1 (en) * 2008-12-09 2010-06-10 Begley William J Oled device with cyclobutene electron injection materials
US7968215B2 (en) 2008-12-09 2011-06-28 Global Oled Technology Llc OLED device with cyclobutene electron injection materials
US20100207513A1 (en) * 2009-02-13 2010-08-19 Begley William J Oled with fluoranthene-macrocyclic materials
US8216697B2 (en) 2009-02-13 2012-07-10 Global Oled Technology Llc OLED with fluoranthene-macrocyclic materials
US20110024770A1 (en) * 2009-02-27 2011-02-03 Tutt Lee W Inverted Bottom-Emitting OLED Device
US20100219748A1 (en) * 2009-02-27 2010-09-02 Kondakova Marina E Oled device with stabilized green light-emitting layer
US20100219747A1 (en) * 2009-02-27 2010-09-02 Tutt Lee W Inverted bottom-emitting oled device
US8147989B2 (en) 2009-02-27 2012-04-03 Global Oled Technology Llc OLED device with stabilized green light-emitting layer
US8102114B2 (en) 2009-02-27 2012-01-24 Global Oled Technology, Llc. Method of manufacturing an inverted bottom-emitting OLED device
US20100244677A1 (en) * 2009-03-31 2010-09-30 Begley William J Oled device containing a silyl-fluoranthene derivative
WO2010117886A1 (en) 2009-04-06 2010-10-14 Global Oled Technology Llc Organic element for electroluminescent devices
US20100253210A1 (en) * 2009-04-06 2010-10-07 Vargas J Ramon Organic element for electroluminescent devices
US8206842B2 (en) 2009-04-06 2012-06-26 Global Oled Technology Llc Organic element for electroluminescent devices
DE102015114167A1 (en) * 2015-08-26 2017-03-02 Osram Oled Gmbh Light-emitting diode and method for producing a light-emitting diode

Similar Documents

Publication Publication Date Title
US3710167A (en) Organic electroluminescent cells having a tunnel injection cathode
US4081764A (en) Zinc oxide light emitting diode
JP3281533B2 (en) Cold electron emission display device and semiconductor cold electron emission element
US4140937A (en) Direct current electroluminescent devices
US5984752A (en) Electron emission cathode; an electron emission device, a flat display, a thermoelectric cooling device incorporating the same; and a method for producing the electron emission cathode
US3814968A (en) Solid state radiation sensitive field electron emitter and methods of fabrication thereof
US4486499A (en) Electroluminescent device
JPH021327B2 (en)
US3699404A (en) Negative effective electron affinity emitters with drift fields using deep acceptor doping
US3267317A (en) Device for producing recombination radiation
US4082889A (en) Luminescent material, luminescent thin film therefrom, and optical display device therewith
US3184636A (en) Cold cathode
US3274024A (en) Energy converter
US2938136A (en) Electroluminescent lamp
US3330983A (en) Heterojunction electroluminescent devices
US3105166A (en) Electron tube with a cold emissive cathode
US3408521A (en) Semiconductor-type photocathode for an infrared device
US3986065A (en) Insulating nitride compounds as electron emitters
US3098168A (en) Hot electron cold lattice semiconductor cathode
US3786315A (en) Electroluminescent device
US4373145A (en) Thin film electroluminescent device
JP3187302B2 (en) Electron emission cathode, electron emission element, flat display, and thermoelectric cooling device using the same, and method of manufacturing electron emission cathode
JP3537624B2 (en) Electron-emitting device
US2700626A (en) Secondary electron emissive electrodes
US3242368A (en) Low-voltage hole-injection electroluminescence in cadmium sulphide