Organic EL device, EL display panel, method for manufacturing the organic EL device and method for manufacturing the EL display panel

Abstract

Disclosed is a method for manufacturing an organic EL device which comprises a hole injection layer having a flat surface that is not contaminated. Specifically disclosed method for manufacturing an organic EL device, which comprises a step of forming an anode on a substrate; a step of forming a hole injection layer on the anode; a step of forming an inorganic film on the substrate and the hole injection layer; a step of forming a bank on the inorganic film in such a manner that at least a part of the inorganic film formed on the hole injection layer is exposed; a step of etching the exposed inorganic film by using the bank as a mask so that the hole injection layer is exposed therefrom; and a step of forming an organic light-emitting layer by applying an organic light-emitting material onto the exposed hole injection layer. The hole injection layer contains tungsten oxide or molybdenum oxide.

Description

technical field [0001] The present invention relates to an organic EL (Electroluminescent: electroluminescence) device, an organic EL display panel and a manufacturing method thereof. Background technique [0002] In recent years, research and development on self-luminous displays typified by organic EL displays have been actively conducted as candidates for post-liquid crystal displays and post-plasma displays. There are two types of current organic EL displays. One is a low-molecular-weight organic EL display using a low-molecular-weight organic compound in a light-emitting layer, and the other is a high-molecular-weight organic EL display using a high-molecular organic compound. [0003] Currently, due to the high luminous efficiency and long life of the material, the development of low-molecular-weight organic EL displays that use vacuum processes such as vacuum evaporation to produce the light-emitting layer is in the lead. However, the organic light-emitting layer of...

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Problems solved by technology

However, since the hole transport layer made of metal oxide is dissolved by alkali or water, for example, it may be dissolved during the formation of the bank by etching with an alkali solution, and the surface of the hole transport layer may become deformed. uneven

When the surface of the hole transport layer is uneven, the work function of the hole transport layer is not constant, and the luminous efficiency of the organic EL device may decrease.

In addition, when the hole transport layer is dissolved by an alkaline solution, the surface roughness of the hole transport layer may increase.

If the surface roughness of the hole transport layer increases, it will be difficult for the functional layer formed on the hole transport layer to cover the entire surface of the hole transport layer, so that the organic EL device may be short-circuited.

[0009] In addition, when banks are formed after the formation of the hole transport layer, the surface of the hole transport layer may be contaminated by residues from the banks.

If the surface of the hole transport layer is contaminated by the residue of the bank, the efficiency of the hole transport layer will further vary, and the luminous efficiency of the organic EL device may decrease.

In addition, since the bank is an insulator, after the surface of the hole transport layer is polluted by the residue of the bank, the surface impedance of the hole transport layer increases, and the driving voltage of the organic EL device increases.

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