EL display device and method for producing same
View Patent ↗To provide a device whose life is less likely to be reduced by deterioration of a light-emitting layer material, an EL display device includes: a pixel electrode, for each pixel, above a substrate; auxiliary wiring in a different region, above the substrate, from the pixel electrode; a transition metal oxide layer on the pixel electrode and the auxiliary wiring; a light-emitting layer in a region, above the transition metal oxide layer, corresponding to the pixel; a common electrode continuously above the auxiliary wiring and the light-emitting layer, and electrically connected to the auxiliary wiring; and a material deterioration suppressing layer continuously on a portion of the transition metal oxide layer above the auxiliary wiring and the light-emitting layer, mainly containing barium, and having a thickness equal to or greater than a size of a single barium atom and smaller than 10 nm.
1. An EL display device, comprising:
a pixel electrode provided, for each pixel, above a substrate;
auxiliary wiring provided in a region, above the substrate, different from a region in which the pixel electrode is provided;
a transition metal oxide layer provided at least on the pixel electrode and on the auxiliary wiring;
a light-emitting layer provided at least in a region, above the transition metal oxide layer, corresponding to said each pixel; and
a common electrode provided continuously above the auxiliary wiring and above the light-emitting layer, and electrically connected to the auxiliary wiring, wherein
a material deterioration suppressing layer is provided continuously in physical contact with a portion of the transition metal oxide layer above the auxiliary wiring and in physical contact with the light-emitting layer, the material deterioration suppressing layer containing barium as a major component, and having a thickness that is equal to or greater than a size of a single barium atom and is smaller than 10 nm.
2. The EL display device of claim 1 , wherein
the thickness of the material deterioration suppressing layer is equal to or greater than 5 nm.
3. The EL display device of claim 1 , wherein
an organic functional layer containing barium is provided on the material deterioration suppressing layer, and
the common electrode contains metal oxide.
4. The EL display device of claim 1 , wherein
the light-emitting layer emits blue light, and
the light-emitting layer has a thickness of 70 nm or greater and 90 nm or smaller.
5. The EL display device of claim 1 , wherein
the light-emitting layer emits blue light, and
current density per unit area in the light-emitting layer is 30 mA/cm 2 or higher and 40 mA/cm 2 or lower.
6. The EL display device of claim 1 , wherein
the transition metal oxide layer contains molybdenum or tungsten.
7. The EL display device of claim 1 , wherein
the transition metal oxide layer is a hole injection layer.
8. The EL display device of claim 1 , wherein
the light-emitting layer contains an organic polymeric material.
9. A method for manufacturing an EL display device, comprising:
forming, for each pixel, a pixel electrode above a substrate;
forming auxiliary wiring in a region, above the substrate, different from a region in which the pixel electrode is formed;
forming a transition metal oxide layer continuously on the pixel electrode and on the auxiliary wiring;
forming a light-emitting layer at least in a region, above the transition metal oxide layer, corresponding to said each pixel;
forming a material deterioration suppressing layer continuously in physical contact with a portion of the transition metal oxide layer above the auxiliary wiring and in physical contact with the light-emitting layer, the material deterioration suppressing layer containing barium as a major component, and having a thickness that is equal to or greater than a size of a single barium atom and is smaller than 10 nm; and
forming a common electrode above the material deterioration suppressing layer, the common electrode being electrically connected to the auxiliary wiring.