Organic electronic device manufacturing method and organic EL device manufacturing method

1. An organic electronic device manufacturing method, comprising:

forming a first electrode on a substrate;

forming, on the substrate, a first bank defining a first aperture, such that at least a portion of the first electrode is exposed at a bottom of the first aperture;

forming a first organic functional film by applying a droplet of a first ink into the first aperture, the first ink containing a first organic material;

after the forming of the first organic functional film, forming, on the first bank, a second bank defining a second aperture, the second aperture communicating with the first aperture;

forming a second organic functional film by applying a droplet of a second ink into the second aperture so as to cover a surface of an exposed portion of the first organic functional film, the second ink containing a second organic material differing from the first organic material; and

forming a second electrode on the second organic functional film, wherein

in the forming of the second bank, the second bank is formed such that, in plan view, a bottom edge of a sidewall surface of the second bank facing the second aperture is located at the same position as or is set back from a bottom edge of a sidewall surface of the first bank facing the first aperture, and

in the forming of the second organic functional film, the droplet of the second ink is applied such that an upper edge of the second organic functional film within the second aperture is located at a same level as or at a higher level than the bottom edge of the sidewall surface of the second bank.

2. The organic electronic device manufacturing method of claim 1 , wherein

the forming of the first bank includes:

forming a first bank film on the substrate, the first bank film containing a first bank material; and

forming the first aperture by exposing a portion of the first bank film to light and developing the first bank film by using a first developer,

the forming of the second bank includes:

forming a second bank film on the first bank and the first organic functional film, the second bank film containing a second bank material; and

forming the second aperture by exposing a portion of the second bank film to light and developing the second bank film by using a second developer, and

in the forming of the second bank film during the forming of the second bank, a material that is etchable by using the second developer is used as the second bank material, the first organic functional film being resistant to etching using the second developer.

3. The organic electronic device manufacturing method of claim 2 , wherein

in the forming of the first aperture during the forming of the first bank, alkaline developer is used as the first developer, and

in the forming of the second aperture during the forming of the second bank, aqueous developer is used as the second developer.

4. The organic electronic device manufacturing method of claim 1 , wherein

the forming of the first bank includes applying a liquid-repellent treatment to a surface of the first bank,

the forming of the second bank includes applying a liquid-repellent treatment to a surface of the second bank,

in the applying of a liquid-repellent treatment to the surface of the first bank, the liquid-repellent treatment is performed such that an upper surface of the first bank has a first contact angle relative to the droplet of the first ink, and the sidewall surface of the first bank facing the first aperture has a second contact angle relative to the droplet of the first ink, the first contact angle being greater than the second contact angle, and

in the applying of a liquid-repellent treatment to the surface of the second bank, the liquid-repellent treatment is performed such that an upper surface of the second bank has a third contact angle relative to the droplet of the second ink, and the sidewall surface of the second bank facing the second aperture has a fourth contact angle relative to the droplet of the second ink, the third contact angle being greater than the fourth contact angle.

5. The organic electronic device manufacturing method of claim 4 , wherein

in the applying of a liquid-repellent treatment to the surface of the first bank and the applying of a liquid-repellent treatment to the surface of the second bank, each liquid-repellent treatment is performed such that the third contact angle is greater than the fourth contact angle, the fourth contact angle is greater than the first contact angle, and the first contact angle is greater than the second contact angle.

6. The organic electronic device manufacturing method of claim 2 , wherein

in the forming of the first bank film during the forming of the first bank, the first bank film is formed to have a liquid-repellent surface by using a liquid-repellent material as the first bank material, and

in the forming of the second bank film during the forming of the second bank, the second bank film is formed to have a liquid-repellent surface by using a liquid-repellent material as the second bank material.

7. The organic electronic device manufacturing method of claim 1 , wherein

in the forming of the first organic functional film, the first organic functional film is formed such that an upper edge thereof does not reach the upper surface of the first bank.

8. An organic EL device manufacturing method, comprising:

forming a first electrode on a substrate;

forming, on the substrate, a first bank defining a first aperture, such that at least a portion of the first electrode is exposed at a bottom of the first aperture;

forming a first organic functional film by applying a droplet of a first ink into the first aperture, the first ink containing a first organic material;

after the forming of the first organic functional film, forming, on the first bank, a second bank defining a second aperture, the second aperture communicating with the first aperture;

forming a second organic functional film by applying a droplet of a second ink into the second aperture so as to cover a surface of an exposed portion of the first organic functional film, the second ink containing a second organic material differing from the first organic material; and

forming a second electrode on the second organic functional film, wherein

in the forming of the second bank, the second bank is formed such that, in plan view, a bottom edge of a sidewall surface of the second bank facing the second aperture is located at the same position as or is set back from a bottom edge of a sidewall surface of the first bank facing the first aperture,

in the forming of the second organic functional film, the droplet of the second ink is applied such that an upper edge of the second organic functional film within the second aperture is located at a same level as or at a higher level than the bottom edge of the sidewall surface of the second bank,

in the forming of the first organic functional film, a laminate including a carrier injection layer and a carrier transport layer is formed as the first organic functional film, and

in the forming of the second organic functional film, a light-emitting layer is formed as the second organic functional film, the light-emitting layer causing electroluminescence by recombination of holes and electrons.