OLED Electrode Trench Design for Low Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic light emitting diodes (OLEDs) face challenges in maintaining brightness uniformity and stability due to voltage decreases in transparent electrode layers, especially when used in large-area lighting applications, where high current injection is required, leading to non-uniform light emission and increased resistance.
Innovation Solution
The solution involves forming a trench with concave and convex parts on the substrate to increase the surface area of the electrodes, allowing for a low-resistance electrode without increasing the thickness or line width of the metal auxiliary electrode, thereby minimizing voltage drops and ensuring uniform current injection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the thickness or line width of the metal auxiliary electrode is increased to reduce resistance, then the electroconductivity is improved, but the opening ratio of the light emission region is decreased
Solution Approach 1:
The invention transitions from a planar electrode structure to a three-dimensional structure by forming a trench (concave part) in the substrate and filling it with metal auxiliary electrode material. This vertical dimensionality change increases the electrode surface area and conductive path without occupying additional lateral space, thereby reducing resistance while preserving the opening ratio of the light emission region.
2Illumination intensity
If a high driving current is used to achieve high brightness in large-area OLEDs, then the brightness is improved, but the voltage decrease in the electrode becomes large causing non-uniform current injection
Solution Approach 1:
The invention segments the electrode structure by introducing a metal auxiliary electrode that divides the current injection path into multiple parallel channels: one through the transparent electrode and another through the metal auxiliary electrode in the trench. This segmentation reduces the overall resistance and distributes the current more uniformly across the large-area light emission surface, enabling high brightness while maintaining current uniformity.
Data Source
AI summary
An exemplary embodiment of the present invention provides an organic light emitting diode, comprising a substrate, a first electrode, an organic material layer, and a second electrode, wherein a trench comprising a concave part and a convex part is provided on the substrate, the first electrode is provided on the substrate on which the trench is formed by being deposited, and an auxiliary electrode is provided on the first electrode. The organic light emitting diode according to the exemplary embodiment of the present invention may increase surface areas of the first electrode and the auxiliary electrode formed on the substrate, thereby implementing a low resistance electrode. In addition, since a line width of the electrode is not increased, it is possible to prevent a decrease of an opening ratio of the organic light emitting diode.