OLED light-emitting device, display device, electronic device, and method of manufacturing OLED light-emitting device
A first stack-structured light-emitting element includes light-emitting units and a first charge generation layer between the light-emitting units. A second stack-structured light-emitting element includes light-emitting units and a second charge generation layer between the light-emitting units. Each of the first and second charge generation layers consists of one or more charge generation component layers. A first end region of the first charge generation layer and a second end region of the second charge generation layer overlap above the top face of the element separation layer. In the overlap region, an end region of a component layer of the first or second stack-structured light-emitting element configured to block charges of either polarity is interposed between charge generation component layers of the first and second charge generation layers configured to generate charges of the same polarity as the charges to be blocked by the component layer.
1. An OLED light-emitting device comprising:
an element separation layer having openings defining light-emitting regions and a top face between the openings;
lower electrodes exposed inside the openings;
a first stack-structured light-emitting element disposed on a first lower electrode of the lower electrodes; and
a second stack-structured light-emitting element disposed on a second lower electrode of the lower electrodes adjacent to the first lower electrode, the second stack-structured light-emitting element being adjacent to the first stack-structured light-emitting element;
wherein the first stack-structured light-emitting element includes a first light-emitting unit and a second light-emitting unit stacked above the element separation layer and a first charge generation layer located between the first light-emitting unit and the second light-emitting unit,
wherein each of the first light-emitting unit and the second light-emitting unit includes a light-emitting layer,
wherein the first charge generation layer includes a first charge generation component layer configured to generate a first charge being a positive charge or a negative charge and a second charge generation component layer located above the first charge generation component layer and configured to generate a second charge having a polarity opposite of the first charge,
wherein the second stack-structured light-emitting element includes a third light-emitting unit and a fourth light-emitting unit stacked above the element separation layer and a second charge generation layer located between the third light-emitting unit and the fourth light-emitting unit,
wherein each of the third light-emitting unit and the fourth light-emitting unit includes a light-emitting layer,
wherein the second charge generation layer includes a third charge generation component layer configured to generate a third charge having a polarity same as the first charge and a fourth charge generation component layer located above the third charge generation component layer and configured to generate a fourth charge having a polarity opposite of the third charge,
wherein a first end region of the first charge generation layer and a second end region of the second charge generation layer overlap above the top face of the element separation layer,
wherein the overlap region includes the first charge generation component layer, the second charge generation component layer, the third charge generation component layer, and the fourth charge generation component layer laid in this order from the bottom,
wherein the second charge generation component layer between the first charge generation component layer and the third charge generation component layer is configured to block the first charge and the third charge, and
wherein the third charge generation component layer between the second charge generation component layer and the fourth charge generation component layer is configured to block the second charge and the fourth charge.
2. The OLED light-emitting device according to claim 1 , wherein, in the overlap region, an end region of the light-emitting layer of the first stack-structured light-emitting element is interposed between the first charge generation layer and the second charge generation layer.
3. The OLED light-emitting device according to claim 1 , wherein the first end region of the first charge generation layer and the second end region of the second charge generation layer are tapered above the top face of the element separation layer.
4. The OLED light-emitting device according to claim 1 ,
wherein the first light-emitting unit and the second light-emitting unit are configured to emit light of a first color,
wherein the third light-emitting unit and the fourth light-emitting unit are configured to emit light of a second color,
wherein each of the first light-emitting unit and the second light-emitting unit includes a hole transport layer,
wherein each of the third light-emitting unit and the fourth light-emitting unit includes a hole transport layer, and
wherein the hole transport layers of the first light-emitting unit and the second light-emitting unit are thicker than the hole transport layers of the third light-emitting unit and the fourth light-emitting unit.
5. A display device including the OLED light-emitting device according to claim 1 .
6. An electronic device including the OLED light-emitting device according to claim 1 .
7. A method of manufacturing an OLED light-emitting device, the method comprising:
forming lower electrodes;
forming an element separation layer having openings to define light-emitting regions and a top face between openings in such a shape that each lower electrode is exposed from an opening; and
forming a first stack-structured light-emitting element and a second stack-structured light-emitting element adjacent to each other above the element separation layer,
wherein the first stack-structured light-emitting element includes a first light-emitting unit and a second light-emitting unit stacked above the element separation layer and a first charge generation layer located between the first light-emitting unit and the second light-emitting unit,
wherein each of the first light-emitting unit and the second light-emitting unit includes a light-emitting layer,
wherein the first charge generation layer includes a first charge generation component layer configured to generate a first charge being a positive charge or a negative charge and a second charge generation component layer located above the first charge generation component layer and configured to generate a second charge having a polarity opposite of the first charge,
wherein the second stack-structured light-emitting element includes a third light-emitting unit and a fourth light-emitting unit stacked above the element separation layer and a second charge generation layer located between the third light-emitting unit and the fourth light-emitting unit,
wherein each of the third light-emitting unit and the fourth light-emitting unit includes a light-emitting layer,
wherein the second charge generation layer includes a third charge generation component layer configured to generate a third charge having a polarity same as the first charge and a fourth charge generation component layer located above the third charge generation component layer and configured to generate a fourth charge having a polarity opposite of the third charge,
wherein a first end region of the first charge generation layer and a second end region of the second charge generation layer overlap above the top face of the element separation layer,
wherein the overlap region includes the first charge generation component layer, the second charge generation component layer, the third charge generation component layer, and the fourth charge generation component layer laid in this order from the bottom,
wherein the second charge generation component layer between the first charge generation component layer and the third charge generation component layer is configured to block the first charge and the third charge, and
wherein the third charge generation component layer between the second charge generation component layer and the fourth charge generation component layer is configured to block the second charge and the fourth charge.
8. The method according to claim 7 , further comprising:
forming the first charge generation component layer of the first charge generation layer by vapor deposition with a metal mask placed at a first position;
placing the metal mask at a second position by moving the metal mask from the first position after forming the first charge generation component layer; and
forming the third charge generation component layer of the second charge generation layer by vapor deposition of same material as the first charge generation component layer with the metal mask placed at the second position.