Organic electroluminescent element, organic electroluminescent unit, and electronic apparatus
An organic electroluminescent element according to one embodiment of the disclosure includes, in order, an anode, an organic light-emitting layer, an electron transport layer, an intermediate layer, and a cathode. The electron transport layer includes a sodium fluoride layer. The intermediate layer includes an ytterbium layer. The ytterbium layer is in contact with the sodium fluoride layer on side of the cathode.
1. An organic electroluminescent element comprising, in order:
an anode;
an organic light-emitting layer,
an electron transport layer including a sodium fluoride layer, wherein the electron transport layer is in direct physical contact with the organic light-emitting layer,
an intermediate multilayer comprising a plurality of layers, including an ytterbium layer;
a cathode multilayer;
the ytterbium layer being in contact with the sodium fluoride layer on side of the cathode multilayer;
a distance from the anode to the cathode multilayer is an optical length in which a cavity is generated, and
the cathode multilayer includes a translucent metal layer or a reflective metal layer at an interface on side of the electron transport layer.
2. The organic electroluminescent element according to claim 1 , wherein the sodium fluoride layer is in contact with the organic light-emitting layer.
3. The organic electroluminescent element according to claim 1 , wherein the cathode multilayer is in contact with the ytterbium layer.
4. The organic electroluminescent element according to claim 1 , wherein the intermediate multilayer includes a film thickness adjusting layer provided at the ytterbium layer on the side of the cathode multilayer, the film thickness adjusting layer including a transparent electrically-conductive material.
5. The organic electroluminescent element according to claim 4 , wherein the intermediate multilayer includes a silver underlayer that is in contact with the film thickness adjusting layer on the side of the electron transport layer.
6. The organic electroluminescent element according to claim 5 , wherein the intermediate multilayer includes an ytterbium film quality adjusting layer provided at the film thickness adjusting layer on the side of the cathode multilayer.
7. The organic electroluminescent element according to claim 4 , wherein the intermediate multilayer includes an ytterbium film quality adjusting layer provided at the film thickness adjusting layer on the side of the cathode multilayer.
8. The organic electroluminescent element according to claim 3 , wherein the cathode multilayer includes an ytterbium cap layer that is in contact with the translucent metal layer or the reflective metal layer on side opposite to the electron transport layer.
9. The organic electroluminescent element according to claim 1 , wherein the ytterbium layer has a thickness in a range from 0.1 nm to 10 nm.
10. The organic electroluminescent element according to claim 1 , wherein the sodium fluoride layer has a thickness in a range from 0.1 nm to 20 nm.
11. The organic electroluminescent element according to claim 10 , wherein the sodium fluoride layer has a thickness in a range from 0.1 nm to 1 nm.
12. The organic electroluminescent element according to claim 10 , wherein the sodium fluoride layer has a thickness in a range from 15 nm to 20 nm.
13. An organic electroluminescent unit comprising a plurality of organic electroluminescent elements,
one or more of the organic electroluminescent elements including, in order
an anode,
an organic light-emitting layer,
an electron transport layer including a sodium fluoride layer, wherein the electron transport layer is in direct physical contact with the organic light-emitting layer,
an intermediate multilayer comprising a plurality of layers, including an ytterbium layer, and
a cathode multilayer,
the ytterbium layer being in contact with the sodium fluoride layer on side of the cathode multilayer,
wherein the intermediate multilayer includes a metal-doped organic material layer provided at the ytterbium layer on the side of the cathode multilayer.
14. The organic electroluminescent element according to claim 13 , wherein the intermediate multilayer includes a film thickness adjusting layer provided at the metal-doped organic material layer on the side of the cathode multilayer, the film thickness adjusting layer including a transparent electrically-conductive material.
15. The organic electroluminescent element according to claim 14 , wherein the intermediate multilayer includes an ytterbium film quality adjusting layer provided at the film thickness adjusting layer on the side of the cathode multilayer.
16. The organic electroluminescent element according to claim 13 , wherein metal of the metal-doped organic material layer includes ytterbium.
17. An electronic apparatus comprising an organic electroluminescent unit that includes a plurality of organic electroluminescent elements,
one or more of the organic electroluminescent elements including, in order
an anode,
an organic light-emitting layer,
an electron transport layer including a sodium fluoride layer, wherein the electron transport layer is in direct physical contact with the organic light-emitting layer,
an intermediate multilayer comprising a plurality of layers, including an ytterbium layer, and
a cathode multilayer,
the ytterbium layer being in contact with the sodium fluoride layer on side of the cathode multilayer,
wherein the intermediate multilayer includes a metal-doped organic material layer provided at the ytterbium layer on the side of the cathode multilayer.