Method for manufacturing light emitting device
View Patent ↗An object of the present invention to improve reliability of a light emitting device having a mixed layer including an organic compound and metal oxide without reducing productivity. The above object is solved in such a way that after forming the mixed layer including the organic compound and metal oxide, the mixed layer is exposed to a nitrogen gas atmosphere without being exposed to a gas atmosphere including oxygen, and then a stacked film is formed over the mixed layer without exposing the mixed layer to a gas atmosphere including oxygen.
1. A method for manufacturing a light emitting device, comprising:
forming an anode over a substrate;
forming a mixed layer including an organic compound having an arylamine group and molybdenum oxide over the anode by co-evaporation, the mixed layer having a thickness of 60 nm or more;
after forming the mixed layer, spraying the mixed layer with a nitrogen gas for 10 to 180 minutes in a first chamber to expose the mixed layer to a nitrogen gas atmosphere without exposing the mixed layer to a gas atmosphere including oxygen;
after spraying the mixed layer with the nitrogen gas, transferring the substrate to a second chamber without exposing the mixed layer to a gas atmosphere including oxygen;
forming a hole transporting layer over the mixed layer in vacuum in the second chamber without exposing the mixed layer to a gas atmosphere including oxygen;
forming a light emitting layer over the hole transporting layer; and
forming a cathode over the light emitting layer,
wherein after the mixed layer is exposed to the nitrogen gas atmosphere, the nitrogen gas is evacuated, and the mixed layer is exposed to a nitrogen gas atmosphere again.
2. A method for manufacturing a light emitting device, comprising:
forming a cathode over a substrate;
forming an electron transporting layer over the cathode;
forming a light emitting layer over the electron transporting layer;
forming a hole transporting layer over the light emitting layer;
forming a mixed layer including an organic compound having an arylamine group and molybdenum oxide over the hole transporting layer by co-evaporation , the mixed layer having a thickness of 60 nm or more;
after forming the mixed layer, spraying the mixed layer with a nitrogen gas for 10 to 180 minutes in a first chamber to expose the mixed layer to a nitrogen gas atmosphere without exposing the mixed layer to a gas atmosphere including oxygen;
after spraying the mixed layer with the nitrogen gas, transferring the substrate to a second chamber without exposing the mixed layer to a gas atmosphere including oxygen; and
forming an anode over the mixed layer in vacuum in the second chamber without exposing the mixed layer to a gas atmosphere including oxygen,
wherein after the mixed layer is exposed to the nitrogen gas atmosphere, the nitrogen gas is evacuated, and the mixed layer is exposed to a nitrogen gas atmosphere again.
3. A method for manufacturing a light emitting device according to claim 1 , wherein a weight ratio between the organic compound and molybdenum oxide is set to be 95:5 to 20:80 in the mixed layer.
4. A method for manufacturing a light emitting device according to claim 2 , wherein a weight ratio between the organic compound and molybdenum oxide is set to be 95:5 to 20:80 in the mixed layer.
5. A method for manufacturing a light emitting device according to claim 1 , wherein the mixed layer is exposed to the nitrogen gas atmosphere at a room temperature without heating.
6. A method for manufacturing a light emitting device according to claim 2 , wherein the mixed layer is exposed to the nitrogen gas atmosphere at a room temperature without heating.
7. A method for manufacturing a light emitting device according to claim 1 , wherein an amount of moisture in the nitrogen gas is 40 ppm or less and the nitrogen gas is introduced in the first chamber at a flow rate of 1 to 500 sccm.
8. A method for manufacturing a light emitting device according to claim 2 , wherein an amount of moisture in the nitrogen gas is 40 ppm or less and the nitrogen gas is introduced in the first chamber at a flow rate of 1 to 500 sccm.