Method for manufacturing light emitting device

Abstract

Provided is a method for manufacturing a light emitting device that includes, on a substrate, a plurality of lower electrodes, a first, a second and a third organic layers each formed on one of the lower electrodes to emit light of a color different from each other, and a upper electrode opposite to the lower electrodes sandwiching the first, the second or the third organic layer. The method includes forming the first organic layer on the plurality of lower electrodes, removing the first organic layer on a certain lower electrode to expose the lower electrode, and then forming a new organic layer on the exposed lower electrode, and repeating this processing for the second and third organic layers.

Description

technical field [0001] The present invention relates to a method of manufacturing a light emitting device. More specifically, the present invention relates to a method of manufacturing a light emitting device such as a display device or a lighting device including an organic electroluminescence (organic EL) element. Background technique [0002] In recent years, as a flat panel display, an organic EL display device, which is a self-luminous type device, has attracted attention. The organic EL display device means a display device using, as a display element, an organic EL element including a pair of electrodes and an organic layer disposed between the pair of electrodes. An organic EL display device that performs color display uses a configuration in which organic EL elements for emitting white light are combined with color filters of various colors, or for emitting light such as red, green, and blue. A plurality of types of organic EL elements of mutually different colors...

AI Technical Summary

Problems solved by technology

[0011] The first problem is that the reaction between the electrode material and the etching gas produces compounds on the surface of the lower electrode, and the re-attachment of the reaction products to the surface of the lower electrode reduces the cleanliness of the lower electrode surface

Decrease in cleanliness of the lower electrode surface leads to deterioration of hole or electron injection characteristics from the lower electrode into the organic layer

Therefore, a reduction in luminous efficiency, an increase in power consumption due to a higher driving voltage, or display failure such as uneven light emission occurs

In particular, when an alloy material containing Al or Ag is used for the lower electrode, a reactive compound with the etching gas is easily generated on the surface of the lower electrode, and such a problem is conspicuous

When a material such as indium tin oxide (ITO), indium zinc oxide (IZO) or magnesium oxide (MgO) is formed in the surface of the lower electrode x ) and the like, although no reactive compound is generated, the degree of surface oxidation of the oxide transparent conductive film changes, thereby deteriorating the hole or electron injection characteristics into the organic layer

[0012] The second problem is that due to the etching of the surface of the lower electrode, the surface smoothness is reduced to cause local concentration of current, thereby reducing the luminous efficiency

Therefore, the cleanliness or smoothness decreases the most on the surface of the lower electrode forming the organic EL layer of the third color

As a result, reduction in luminous efficiency or display failure frequently occurs in the organic EL element forming the organic EL layer of the third color, thereby reducing the yield of the organic EL display device

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