Granted Patent B2

US 12,745,514 · App. 18/287,425 · Granted Sep 22, 2026

Inventors: Sentaro Kida (Sakai City, JP); Jun Sakuma (Sakai City, JP); Yasushi Asaoka (Sakai City, JP)

Assignee: SHARP KABUSHIKI KAISHA

H10K59/122H10K50/115H10K50/13H10K59/1201H10K59/131H10K71/221

Abstract

Claims (67)

1 . A method for manufacturing a display device, the method comprising:

forming a first resist layer over a substrate;

patterning the first resist layer by removing, through exposure and development, the first resist layer formed above a first region of the substrate;

forming a first light-emitting material layer over the patterned first resist layer and above the first region of the substrate with the first resist layer removed;

forming a second resist layer over the first light-emitting material layer;

patterning the second resist layer by removing, through exposure and development, the first resist layer formed above a second region of the substrate, followed by lifting off the first light-emitting material layer and the second resist layer formed over the first resist layer above the second region; and

forming a second light-emitting material layer over the patterned second resist layer and above the second region of the substrate.

2 . The method according to claim 1 , further comprising:

after forming the second light-emitting layer, forming light-emitting layers by removing, through exposure and development, the second resist layer formed over the first light-emitting material layer above the first region of the substrate, followed by lifting off the second light-emitting material layer formed over the second resist layer above the first region, to produce a first light-emitting layer that is the first light-emitting material layer formed over the first region, and to produce a second light-emitting layer that is the second light-emitting material layer formed over the second region.

3 . The method according to claim 1 , further comprising:

after forming the second light-emitting layer-step f), forming a third resist layer over the second light-emitting material layer;

patterning the third resist layer by removing, through exposure and development, the first resist layer formed above a third region of the substrate, followed by lifting off the first light-emitting material layer, the second resist layer, the second light-emitting material layer, and the third resist layer formed over the first resist layer above the third region; and

forming a third light-emitting material layer over the patterned third resist layer and above the third region of the substrate with the first resist layer removed.

4 . The method according to claim 3 , further comprising:

after forming the third light-emitting material layer, forming light-emitting layers individually by removing, through exposure and development, the second resist layer formed over the first light-emitting material layer above the first region of the substrate, followed by lifting off the second light-emitting material layer, the third resist layer, and the third light-emitting material layer formed over the second resist layer above the first region, and by removing, through exposure and development, the third resist layer formed over the second light-emitting material layer above the second region of the substrate, followed by lifting off the third light-emitting material layer formed over the third resist layer above the second region, to produce a first light-emitting layer that is the first light-emitting material layer formed over the first region, to produce a second light-emitting layer that is the second light-emitting material layer formed over the second region, and to produce a third light-emitting layer that is the third light-emitting material layer formed over the third region.

5 . The method according to claim 4 , wherein a developing solution, that is used in patterning the third resist layer, is an alkaline developing solution having an alkali concentration that enables liftoff of the first light-emitting material layer, the second resist layer, the second light-emitting material layer, and the third resist layer formed over the first resist layer in the third region.

6 . The method according to claim 4 , wherein patterning the third resist layer is performed through spray development, spin development, or ultrasonic development.

7 . The method according to claim 4 , wherein the first resist layer, that is removed in the liftoff in each of patterning the second resist layer and patterning the third resist layer, and the second and third resist layers, that are removed in the liftoff in forming the individual light-emitting layers, are formed so as to have an invertedly tapered shape tapering down toward the substrate.

8 . The method according to claim 4 , wherein a liquid-repellent layer containing a liquid-repellent ingredient is formed on an upper surface of each of the first resist layer, the second resist layer, and the third resist layer.

9 . The method according to claim 4 , wherein;

above the substrate, a bank, defining ends of light-emitting regions where light is emitted in the first, second, and third light-emitting layers, is provided upright, and

each of the first resist layer, the second resist layer, and the third resist layer is thicker than the bank.

10 . The method according to claim 4 , wherein the third resist layer is thicker than the second resist layer, which is thicker than the first resist layer.

11 . The method according to claim 4 , wherein

the first light-emitting layer contains a first quantum dot,

the second light-emitting layer contains a second quantum dot,

the third light-emitting layer contains a third quantum dot, and

a ratio of ligands coordinating with the second quantum dot is smaller than a ratio of ligands coordinating with the first quantum dot and the ligands coordinating with the third quantum dot.

12 . The method according to claim 11 , wherein the second light-emitting layer is a light-emitting layer that emits red light.

13 . The method according to claim 11 , wherein at least one of the first quantum dot, the second quantum dot, and the third quantum dot contains indium phosphide.

14 . A method for manufacturing a display device, the method comprising:

forming a first resist layer over a substrate;

patterning the first resist layer by removing, through exposure and development, the first resist layer formed above a first region of the substrate;

forming a first charge-transport material layer over the patterned first resist layer and above the first region of the substrate with the first resist layer removed;

forming a first light-emitting material layer over the first charge-transport material layer;

forming a second resist layer over the first light-emitting material layer;

patterning the second resist layer by removing, through exposure and development, the first resist layer formed above a second region of the substrate, followed by lifting off the first charge-transport material layer, the first light-emitting material layer, and the second resist layer formed over the first resist layer above the second region;

forming a second charge-transport material layer over the patterned second resist layer and above the second region of the substrate with the first resist layer removed; and

forming a second light-emitting material layer over the second charge-transport material layer.

15 . The method according to claim 14 , further comprising:

after forming the second light-emitting material layer, forming a third resist layer over the second light-emitting material layer;

patterning the third resist layer by removing, through exposure and development, the first resist layer formed over a third region of the substrate, followed by lifting off the first charge-transport material layer, the first light-emitting material layer, the second resist layer, the second charge-transport material layer, the second light-emitting material layer, and the third resist layer formed above the third region;

forming a third charge-transport material layer over the patterned third resist layer and above the third region of the substrate; and

forming a third light-emitting material layer over the third charge-transport material layer.

16 . The method according to claim 15 , further comprising:

after forming the third light-emitting material layer, forming light-emitting layers and charge transport layers individually by removing, through exposure and development, the second resist layer formed over the first light-emitting material layer above the first region of the substrate, followed by lifting off the second charge-transport material layer, the second light-emitting material layer, the third resist layer, the third charge-transport material layer, and the third light-emitting material layer formed over the second resist layer above the first region, and by removing, through exposure and development, the third resist layer formed over the second light-emitting material layer above the second region of the substrate, followed by lifting off the third charge-transport material layer and the third light-emitting material layer formed over the third resist layer above the second region, to produce a first light-emitting layer and a first individualized charge transport layer that are the first light-emitting material layer and the first charge-transport material layer formed above the first region, to produce a second light-emitting layer and a second individualized charge transport layer that are the second light-emitting material layer and the second charge-transport material layer formed above the second region, and to produce a third light-emitting layer and a third individualized charge transport layer that are the third light-emitting material layer and the third charge-transport material layer formed above the third region, wherein:

the first individualized charge transport layer contains a first nanoparticle,

the second individualized charge transport layer contains a second nanoparticle,

the third individualized charge transport layer contains a third nanoparticle, and

a ratio of ligands coordinating with the second nanoparticle is smaller than a ratio of ligands coordinating with the first nanoparticle and the ligands coordinating with the third nanoparticle.

17 . A display device comprising:

a plurality of pixel electrodes disposed in correspondence with a plurality of subpixel formation regions;

a first common charge transport layer provided over the plurality of pixel electrodes;

a first light-emitting layer and a second light-emitting layer, each provided, over the first common charge transport layer, in a location facing a corresponding one of the plurality of pixel electrodes;

a bank provided upright so as to define ends of light-emitting regions where light is emitted in the first and second light-emitting layers;

a common electrode provided over both of the first light-emitting layer and the second light-emitting layer, the first common charge transport layer and the common electrode being disposed over the bank; and

a resist layer provided in a location overlapping the bank in a plan view, and between the first common charge transport layer and the common electrode.

18 . The display device according to claim 17 , wherein

a stack including the first light-emitting layer, the second light-emitting layer, and the resist layer is formed over the bank, and

the resist layer is disposed between the first common charge transport layer and the first and second light-emitting layers.

19 . The display device according to claim 17 , further comprising:

an effective display region; and

a frame region disposed around the effective display region,

wherein the first common charge transport layer is not provided in the frame region.

20 . The display device according to claim 19 , wherein

the common electrode is disposed astride both of the effective display region and the frame region, and

the frame region includes a connecting portion connecting together a wire connected to an external power source and the common electrode.

Assignments (1)

Continuity (1)

References Cited (13)