Intermediate connector for stacked organic light emitting devices

• US 8,372,526 B2
• Filed: 07/16/2008
• Issued: 02/12/2013
• Est. Priority Date: 07/16/2008
• Status: Active Grant

• Current Assignee: Universal Display Corporation
• Original Assignee: Universal Display Corporation
• Inventors: D'Andrade, Brian
• Primary Examiner(s): Garrett, Dawn L.
• Assistant Examiner(s): Bohaty, Andrew K
• Application Number:
  US12/174,286
• Publication Number:
  US 20100013378A1
• Time in Patent Office: 1,672 Days
• Field of Search: None
• US Class Current: 428/690
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: C09K 2211/1022 bridged by heteroatoms, e.g. N, P, Si or B
• CPC Class Codes: C09K 2211/1029 containing one nitrogen atom as the heteroatom
• CPC Class Codes: C09K 2211/1044 containing two nitrogen atoms as heteroatoms
• CPC Class Codes: C09K 2211/1059 containing three nitrogen atoms as heteroatoms
• CPC Class Codes: C09K 2211/1092 containing sulfur as the only heteroatom
• CPC Class Codes: C09K 2211/185 of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd
• CPC Class Codes: H05B 33/26 characterised by the composition or arrangement of the conductive material used as an electrode
• CPC Class Codes: H10K 50/19 Tandem OLEDs
• CPC Class Codes: H10K 59/32 Stacked devices having two or more layers, each emitting at different wavelengths
• CPC Class Codes: H10K 85/342 comprising iridium
• CPC Class Codes: H10K 85/622 containing four rings, e.g. pyrene
• CPC Class Codes: H10K 85/626 containing more than one polycyclic condensed aromatic rings, e.g. bis-anthracene
• CPC Class Codes: H10K 85/6572 comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole

Abstract

A device is provided, having an anode, a cathode, and an intermediate connector disposed between the anode and the cathode. A first organic layer including an emissive sublayer is disposed between the anode and the intermediate connector, and a second including an emissive sublayer is disposed between the intermediate connector and the cathode. The intermediate connector includes a first metal having a work function lower than 4.0 eV and a second metal having a work function lower than 5.0 eV. The work function of the first metal is at least 0.5 eV less than the work function of the second metal. The first metal is in contact with a sublayer of the second organic layer that includes a material well adapted to receive holes from a low work function metal.

Claims

1. A device, comprising:

an anode;

a cathode;

an intermediate connector disposed between the anode and the cathode, the intermediate connector comprising;

a first metal having a work function lower than 4.0 eV; and

a second metal having a work function lower than 5.0 eV;

wherein the work function of the first metal is at least 0.5 eV less than the work function of the second metal;

a first layer consisting essentially of the first metal, the first layer being in direct contact with the first sublayer of the second organic layer; and

a second layer consisting essentially of the second metal, the second layer being in direct contact with the first layer, and disposed closer to the anode than the first layer;

a first organic layer disposed between the anode and the intermediate connector, the first organic layer further comprising a first organic emissive material;

a second organic layer disposed between the intermediate connector and the cathode, the second organic layer comprising a plurality of sublayers, including a first sublayer of the second organic layer and a second sublayer of the second organic layer;

the first sublayer of the second organic layer being in direct contact with the intermediate connector, and comprising a material having the structure;

2. The device of claim 1, wherein the intermediate connector further comprises a third layer in contact with the second layer, the third layer being disposed closer to the anode than the second layer, the third layer comprising a metal halide or metal oxide.

3. The device of claim 2, wherein the metal halide or metal oxide is LiF, the first metal is Ca, and the second metal is Al.

4. The device of claim 1, wherein the intermediate connector further comprises:

a first layer consisting essentially of the first metal, the first layer in direct contact with the first sublayer of the second organic layer;

a second layer consisting essentially of the second metal, the second layer being in direct contact with the first layer, and disposed closer to the anode than the first layer;

a third layer in contact with the second layer, the third layer being disposed closer to the anode than the second layer, the third layer comprising a metal halide or metal oxide;

a fourth layer consisting essentially of the first metal, the fourth layer in direct contact with the third layer, and disposed closer to the anode than the third layer;

a fifth layer consisting essentially of the second metal, the fifth layer being in direct contact with the fourth layer, and disposed closer to the anode than the fourth layer; and

a sixth layer in contact with the fifth layer, the sixth layer being disposed closer to the anode than the fifth layer, the sixth layer comprising a metal halide or metal oxide.

5. The device of claim 1, wherein the first organic emissive material is a fluorescent material, and the second organic emissive material is a phosphorescent material.

6. The device of claim 5, wherein the first organic emissive material is a fluorescent material having a peak emissive wavelength in the visible spectrum that is less than 550 nm, and the second organic emissive material is a phosphorescent emissive material having a peak emissive wavelength in the visible spectrum that is greater than 550 nm.

7. The device of claim 6, wherein the device emits light having a CRI greater than 89.

8. The device of claim 1, wherein the intermediate connector is non-addressable.

9. The device of claim 1, wherein the first organic layer further comprising a plurality of sublayers, including a first sublayer of the first organic layer and a second sublayer of the first organic layer;

the first sublayer of the first organic layer is in direct contact with the intermediate connector;

the first sublayer of the first organic layer is not conductivity doped; and

the first sublayer of the second organic layer is not conductivity doped.

10. The device of claim 2, wherein the first sublayer of the second organic layer comprises a material having the structure:

11. A consumer product comprising a device, the device further comprising:

an anode;

a cathode;

an intermediate connector disposed between the anode and the cathode, the intermediate connector comprising;

a first metal having a work function lower than 4.0 eV; and

a second metal having a work function lower than 5.0 eV;

wherein the work function of the first metal is at least 0.5 eV less than the work function of the second metal;

a first layer consisting essentially of the first metal, the first layer being in direct contact with the first sublayer of the second organic layer; and

a second layer consisting essentially of the second metal, the second layer being in direct contact with the first layer, and disposed closer to the anode than the first layer;

a first organic layer disposed between the anode and the intermediate connector, the first organic layer further comprising a first organic emissive material;

a second organic layer disposed between the intermediate connector and the cathode, the second organic layer comprising a plurality of sublayers, including a first sublayer of the second organic layer and a second sublayer of the second organic layer;

the first sublayer of the second organic layer being in direct contact with the intermediate connector, and comprising a material having the structure;