Light emitting device including planarization layer, method of manufacturing the light emitting device, and display apparatus including the light emitting device

A display apparatus comprising:

• a first pixel configured to emit light of a first wavelength;
• and
• a second pixel configured to emit light of a second wavelength different from the first wavelength,
• wherein the first pixel comprises:
• a reflective layer comprising a plurality of nanostructures that are periodically two-dimensionally arranged;
• a planarization layer disposed on the reflective layer;
• a first electrode disposed on the planarization layer;
• an organic emission layer disposed on the first electrode, the organic emission layer being configured to emit visible light comprising the light of the first wavelength and the light of the second wavelength;
• and
• a second electrode disposed on the organic emission layer,
• wherein the planarization layer comprises a conductive material that is transparent with respect to light emitted by the organic emission layer, and
• wherein the planarization layer is disposed on upper surfaces of the plurality of nanostructures such that an air gap is provided between adjacent nanostructures of the plurality of nanostructures.

A method of manufacturing a light emitting device, the method comprising:

• coating a substrate with a mixture of graphene oxide and tetramethyl orthosilicate (TMOS) sol in a solvent;
• curing the mixture coated on the substrate;
• annealing the cured mixture to reduce graphene oxide to reduced graphene oxide and form a planarization layer comprising an organic-inorganic hybrid layer in which the reduced graphene oxide is dispersed;
• transferring the planarization layer to a reflective layer comprising a plurality of nanostructures that are periodically two-dimensionally arranged;
• disposing a first electrode on the planarization layer;
• disposing an organic emission layer on the first electrode;
• and
• disposing a second electrode on the organic emission layer,
• wherein the planarization layer is conductive and transparent with respect to light emitted by the organic emission layer,
• wherein the planarization layer is disposed on upper surfaces of the plurality of nanostructures such that an air gap is provided between adjacent nanostructures the plurality of nanostructures.

A light emitting device comprising:

• a reflective layer comprising:
• a plurality of nanostructures that are periodically two-dimensionally provided;
• and
• a plurality of recesses that are periodically two-dimensionally provided;
• a planarization layer disposed on the reflective layer;
• a first electrode disposed on the planarization layer;
• an organic emission layer disposed on the first electrode;
• and
• a second electrode disposed on the organic emission layer,
• wherein the planarization layer comprises a conductive material transparent with respect to light emitted by the organic emission layer,
• wherein the planarization layer is disposed on upper surfaces of the plurality of nanostructures such that an air gap is provided between adjacent nanostructures of the plurality of nanostructures, and
• wherein the planarization layer further comprises an organic-inorganic hybrid layer in which reduced graphene oxide is dispersed.