Organic light emitting device and method for manufacturing same

1. A light emitting device, comprising:

a base substrate;

a plurality of first electrodes on the base substrate;

a plurality of banks extending along a periphery of the first electrodes above a surface of the base substrate; and

a plurality of light emitting elements extending along a direction in a plurality of groove regions defined by the banks; and

a plurality of second electrodes covering the light emitting elements,

wherein

each of the light emitting elements includes one or more functional layers between the first electrodes and the second electrodes,

within at least one of the groove regions:

a sub-bank extends along the direction and has a height equal to or smaller than a height of the banks,

for each of the one or more functional layers in the at least one of the groove regions, portions of each of the one or more functional layers on each side of the sub-bank are made of a same material, and

a thickness of the one or more functional layers is smaller than a height of the sub-bank.

2. The light emitting device according to claim 1 , wherein

the sub-bank is continuous, in the direction, from one end to another end of each of the light emitting elements in the at least one of the groove regions.

3. The light emitting device according to claim 1 , wherein

an upper end of the sub-bank is closer to the surface of the base substrate than an upper end of each of the banks.

4. The light emitting device according to claim 1 , wherein

a plurality of second banks is in each of the groove regions, the second banks partitioning, in the direction, the one or more functional layers of adjacent light emitting elements.

5. The light emitting device according to claim 4 , wherein

an upper end of each of the second banks is closer to the surface of the base substrate than an upper end of each of the banks.

6. The light emitting device according to claim 5 , wherein

the second banks and the sub-bank have a same height.

7. The light emitting device according to claim 1 , wherein

in the at least one of the groove regions in which the sub-bank extends, each of the first electrodes which is under the one or more functional layers spans the portions of the one or more functional layers on each side of the sub-bank.

8. The light emitting device according to claim 7 , wherein

in the at least one of the groove regions in which the sub-bank extends, each of the first electrodes is under peripheral portions of the banks which define the at least one of the groove regions.

9. The light emitting device according to claim 8 , wherein

each of the first electrodes is provided separately for one of the light emitting elements.

10. The light emitting device according to claim 1 , wherein

each of the at least one of the groove regions in which the sub-bank extends has a groove width of at least 80 μm, and

each of the portions of each of the one or more functional layers on each side of the sub-bank has a width of at most 80 μm.

11. The light emitting device according to claim 1 , wherein

each of the at least one of the groove regions in which the sub-bank extends includes small and large groove widths, and

the sub-bank is disposed at least in a groove region having a largest groove width among the groove widths.

12. The light emitting device according to claim 1 , wherein

in the at least one of the groove regions in which the sub-bank extends, the sub-bank is above the substrate and each of the first electrodes and below each of the one or more functional layers of each of the light emitting elements.

13. The light emitting device according to claim 12 , wherein

in the at least one of the groove regions in which the sub-bank extends, each of the light emitting elements is directly on the sub-bank.

14. The light emitting device according to claim 1 , wherein

the sub-bank has a lower liquid repellency than the banks.

15. The light emitting device according to claim 1 , wherein

the sub-bank and the banks comprise a same material.