ORGANIC ELECTROLUMINESCENCE DISPLAY PANEL AND METHOD OF MANUFACTURING THE SAME

• US 20160172423A1
• Filed: 12/08/2015
• Published: 06/16/2016
• Est. Priority Date: 12/10/2014
• Status: Active Grant

• Current Assignee: JDI Design and Development GK
• Original Assignee: JOLED Inc.
• Inventors: NENDAI, Kenichi
• Granted Patent: US 9,818,808 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H10K 59/1201 Manufacture or treatment
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 71/135 using ink-jet printing

Abstract

An organic EL display panel including: a substrate; a first lower electrode and a second lower electrode disposed over the substrate with a gap therebetween in a first direction; a wall separating a space above the first lower electrode and a space above the second lower electrode from one another; organic light-emitting layers respectively disposed in the spaces; and an upper electrode extending over the organic light-emitting layers. The wall includes a first portion disposed over the gap and two second portions each of which is disposed over a different one of the first lower electrode and the second lower electrode. The first portion is between the two second portions in the first direction, and at least a part of a bottom face of the first portion is positioned higher than a bottom face of the second portion.

Claims

1. An organic electroluminescence display panel, comprising:

a substrate;

a first lower electrode and a second lower electrode disposed over the substrate and spaced away from one another in a first direction along a top face of the substrate by a gap therebetween;

a partition wall made of an electrically insulating material and separating a space above the first lower electrode and a space above the second lower electrode from one another, the partition wall including a first portion disposed over the gap and two second portions each of which is disposed over a different one of the first lower electrode and the second lower electrode, the first portion disposed between the two second portions in the first direction;

a first organic light-emitting layer and a second organic light-emitting layer respectively disposed in the space above the first lower electrode and the space above the second lower electrode; and

an upper electrode extending over the first organic light-emitting layer and the second organic light-emitting layer, wherein

at least a part of a bottom face of the first portion is positioned higher than a bottom face of the second portion.

2. The organic electroluminescence display panel according to claim 1, wherein

in the first direction, a central part of the bottom face of the first portion is positioned higher than the bottom face of the second portion.

3. The organic electroluminescence display panel according to claim 1, further comprising

a convex layer made of an electrically insulating material between the substrate and the first portion, having greater thickness than the first lower electrode and the second lower electrode.

4. The organic electroluminescence display panel according to claim 3, further comprising

an inter-layer insulating layer made of a resin material and disposed over the substrate, a shape of a top face of the inter-layer insulating layer in conformity with a shape of the top face of the substrate, wherein

the convex layer is made of the resin material, and

the first lower electrode, the second lower electrode, and the convex layer are disposed over the inter-layer insulating layer.

5. The organic electroluminescence display panel according to claim 3, further comprising

an inter-layer insulating layer made of a resin material and disposed over the substrate and the convex layer, a shape of a top face of the inter-layer insulating layer in conformity with a combination of a shape of the top face of the substrate and a top face of the convex layer, wherein

the convex layer is made of the resin material, and

the first lower electrode and the second lower electrode are disposed over the inter-layer insulating layer.

6. The organic electroluminescence display panel according to claim 1, further comprising

an inter-layer insulating layer made of a resin material and disposed over the substrate, a shape of a top face of the inter-layer insulating layer in conformity with a shape of the top face of the substrate, wherein

the inter-layer insulating layer includes a planar portion on which the first lower electrode and the second lower electrode are disposed and a convex portion on the planar portion, the convex portion corresponding in position to the gap and protruding upward higher than a top face of the first lower electrode and a top face of the second lower electrode.

7. The organic electroluminescence display panel according to claim 1, wherein

in a second direction that is along the top face of the substrate and that is perpendicular to the first direction, the first lower electrode is provided in plurality to form a line of first lower electrodes, and the second lower electrode is provided in plurality of form a line of second lower electrodes,

the first organic light-emitting layer extends in the second direction over the line of first lower electrodes, and the second organic light-emitting layer extends in the second direction over the line of second lower electrodes, and

the partition wall extends in the second direction between the first organic light-emitting layer and the second organic light-emitting layer, and in any cross-section taken along the second direction, at least a part of the bottom face of the first portion is positioned higher than the bottom face of the second portion.

8. The organic electroluminescence display panel according to claim 7, further comprising

a convex layer formed from an electrically insulating material, disposed between the substrate and the first portion, and extending in the second direction, wherein

the convex layer has greater thickness than the first lower electrodes and the second lower electrodes.

9. The organic electroluminescence display panel according to claim 8, further comprising

a pixel insulation layer formed from an electrically insulating material, extending in the first direction, and disposed between electrodes adjacent in the second direction, the electrodes adjacent in the second direction comprising a combination of two first lower electrodes and a combination of two second lower electrodes, wherein

the pixel insulation layer has greater thickness than the first lower electrodes and the second lower electrodes, and has smaller thickness than the convex layer.

10. The organic electroluminescence display panel according to claim 9, wherein

the convex layer and the pixel insulation layer form a single layer.

11. The organic electroluminescence display panel according to claim 1, wherein

a color of light emitted by the first organic light-emitting layer differs from a color of light emitted by the second organic light-emitting layer.

12. An organic electroluminescence display panel manufacturing method, comprising:

preparing a substrate;

forming a first lower electrode and a second lower electrode disposed over the substrate and spaced away from one another in a first direction along a top face of the substrate by a gap therebetween;

forming a partition wall by using an electrically insulating material, the partition wall separating a space above the first lower electrode and a space above the second lower electrode from one another and including a first portion disposed over the gap and two second portions each of which being disposed over a different one of the first lower electrode and the second lower electrode, the first portion disposed between the two second portions in the first direction;

performing a wet process to form a first organic light-emitting layer and a second organic light-emitting layer in the space above the first lower electrode and the space above the second lower electrode, respectively; and

forming an upper electrode extending over the first organic light-emitting layer and the second organic light-emitting layer, wherein

at least a part of a bottom face of the first portion is positioned higher than a bottom face of the second portion.

13. The organic electroluminescence display panel manufacturing method according to claim 12 further comprising, before forming the first lower electrode and the second lower electrode:

forming an inter-layer insulating layer over the substrate by using a resin material, a shape of a top face of the inter-layer insulating layer in conformity with a shape of the top face of the substrate; and

forming a convex layer over the interlayer-insulating layer by using the resin material, the convex layer extending in a second direction that is along the top face of the substrate and that is perpendicular to the first direction, wherein

the first lower electrode and the second lower electrode are formed over the inter-layer insulating layer at opposite sides of the convex layer in the first direction and each with smaller thickness than the convex layer, such that at least a part of the bottom face of the first portion is positioned higher than the bottom face of the second portion.

14. The organic electroluminescence display panel manufacturing method according to claim 12 further comprising, before forming the first lower electrode and the second lower electrode:

forming a convex layer over the substrate by using a resin material, the convex layer extending in a second direction that is along the top face of the substrate and that is perpendicular to the first direction; and

forming an inter-layer insulating layer over the substrate and the convex layer by using the resin material, a shape of a top face of the inter-layer insulating layer in conformity with a combination of a shape of the top face of the substrate and a top face of the convex layer, wherein

the first lower electrode and the second lower electrode are formed over the inter-layer insulating layer at opposite sides of the convex layer in the first direction and each with smaller thickness than the convex layer, such that at least a part of the bottom face of the first portion is positioned higher than the bottom face of the second portion.

15. The organic electroluminescence display panel manufacturing method according to claim 12 further comprising, before forming the first lower electrode and the second lower electrode:

applying a resin material over the substrate so that a shape of a top face of a film of the applied resin material is in conformity with a shape of the top face of the substrate; and

forming an inter-layer insulating layer by reducing a thickness of a part of the film with a photolithography method using a half-tone mask, the inter-layer insulating layer including a planar portion whose top face has a shape in conformity with the shape of the top surface of the substrate and a convex portion protruding upward with respect to the planar portion, wherein

the first lower electrode and the second lower electrode are formed over the planar portion at opposite sides of the convex portion in the first direction and each with smaller thickness than the convex portion, such that at least a part of the bottom face of the first portion is positioned higher than the bottom face of the second portion.

16. The organic electroluminescence display panel manufacturing method according to claim 12 further comprising, before forming the first lower electrode and the second lower electrode:

applying a resin material over the substrate so that a shape of a top face of a film of the applied resin material is in conformity with a shape of the top face of the substrate; and

forming an inter-layer insulating layer by reducing a thickness of a part of the film with a photolithography method using dry etching, the inter-layer insulating layer including a planar portion whose top face has a shape in conformity with the shape of the top surface of the substrate and a convex portion protruding upward with respect to the planar portion, wherein

the first lower electrode and the second lower electrode are formed over the planar portion at opposite sides of the convex portion in the first direction and each with smaller thickness than the convex portion, such that at least a part of the bottom face of the first portion is positioned higher than the bottom face of the second portion.

17. The organic electroluminescence display panel manufacturing method according to claim 12, wherein

the first lower electrode and the second lower electrode are formed such that, in a second direction that is along the top face of the substrate and that is perpendicular to the first direction, the first lower electrode is formed in plurality to form a line of first lower electrodes, and the second lower electrode is formed in plurality of form a line of second lower electrodes,

the first organic light-emitting layer is formed to extend in the second direction over the line of first lower electrodes, and the second organic light-emitting layer is formed to extend in the second direction over the line of second lower electrodes, and

the partition wall is formed to extend in the second direction over the gap, and so that in any cross-section taken along the second direction, at least a part of the bottom face of the first portion is positioned higher than the bottom face of the second portion.

18. The organic electroluminescence display panel manufacturing method according to claim 17 further comprising, before forming the first lower electrodes and the second lower electrodes,

forming a convex layer by using an electrically insulating material, the convex layer formed over the substrate to extend in the second direction, wherein

the first lower electrodes and the second lower electrodes are formed at opposite sides of the convex layer in the first direction with smaller thickness than the convex layer, and

in any cross-section of the partition wall taken along the second direction, at least a part of the bottom face of the first portion is positioned higher than the bottom face of the second portion.

19. The organic electroluminescence display panel manufacturing method according to claim 17 further comprising, before forming the partition wall:

applying a resin material along the top face of the substrate having the line of first lower electrodes and the line of second lower electrodes formed thereon, so that a film of the applied resin material has greater thickness than the first lower electrodes and the second lower electrodes; and

forming a convex layer and a pixel insulation layer by removing parts of the film over the first lower electrodes and the second lower electrodes with a photolithography method using a half-tone mask and thereby reducing the thickness of the film at the parts, the convex layer formed to have greater thickness than the first lower electrodes and the second lower electrodes and to extend in the second direction between the line of the first lower electrodes and the line of the second lower electrodes, the pixel insulation layer formed to have greater thickness than the first lower electrodes and the second lower electrodes and smaller thickness than the convex layer and to extend in the first direction between electrodes adjacent in the second direction, the electrodes adjacent in the second direction comprising a combination of two first lower electrodes and a combination of two second lower electrodes, wherein

in any cross-section of the partition wall taken along the second direction, at least a part of the bottom face of the first portion is positioned higher than the bottom face of the second portion.