OLED Through-Hole Encapsulation Structure Against Moisture Ingress
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electroluminescence display devices with through-holes in the display area are vulnerable to water and oxygen permeation, which can compromise their functionality and longevity, especially when these holes are located within the display area.
Innovation Solution
The electroluminescence display device incorporates a substrate with a display area and a non-display area, featuring a through-hole surrounded by an inner dam and a trench, along with an etch-stopper and passivation films, to minimize water and oxygen ingress. This configuration includes an encapsulation layer and a matrix arrangement of light emitting diodes and driving elements, with the trench having a saw-tooth sidewall to disconnect the light emitting layer continuity and enhance encapsulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a through-hole is provided in the display area for additional devices, then the adaptability and functionality of the display device are improved, but the reliability deteriorates due to increased vulnerability to water and oxygen permeation
Solution Approach 1:
The encapsulation structure is segmented into multiple functional components: an inner dam surrounding the through-hole, a trench between the inner dam and through-hole, and an etch-stopper layer. This segmentation creates multiple barrier zones that collectively prevent water and oxygen permeation while accommodating the through-hole for additional devices
Solution Approach 2:
The etch-stopper acts as an intermediary layer between the trench and the through-hole, providing a protective barrier that prevents water and oxygen from reaching the light emitting diode. The insulating layer serves as another intermediary, filling the trench and providing additional protection while maintaining structural integrity
2Area of stationary object
If the non-display area is minimized to maximize display area, then the area efficiency is improved, but the manufacturing complexity increases due to the need for additional encapsulation structures
Solution Approach 1:
The inner dam, trench, and etch-stopper structures are merged into a unified encapsulation system that surrounds the through-hole. The insulating layer is combined with the trench structure, filling it while providing both mechanical support and environmental protection. This merging reduces the overall complexity compared to separate protective structures
Solution Approach 2:
The complex encapsulation structures (inner dam, trench, etch-stopper) are localized only around the through-hole area, while the rest of the display area maintains simple pixel structures. This local quality approach minimizes the impact on overall display area while providing targeted protection where needed
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design maximizes the display area by minimizing the non-display area occupied by the through-hole, effectively prevents water and oxygen from permeating into the light emitting diode, ensuring the stability and longevity of the display device even with a hole in the display panel.
Implementation Method 1
an etch-stopper arranged between the trench and the through-hole on an insulating layer
Implementation Method 2
an electroluminescence display device includes a plurality of electroluminescence diodes. The electroluminescence diode includes an anode electrode, a light emitting layer formed on the anode electrode, and a cathode electrode formed on the light emitting layer. If a high potential voltage is applied to the anode electrode and a low potential voltage is applied to the cathode electrode, holes in the anode electrode and electrons in the cathode electrode respectively move to the light emitting layer. When holes and electrons are combined with each other in the light emitting layer, exciton is formed during an excitation process, and light is generated due to energy from the exciton.
Data Source
AI summary
An electroluminescence display device including a substrate having a display area and a non-display area arranged near the display area, a light emitting diode in the display area, an encapsulation layer on the light emitting diode, the encapsulation layer including a first inorganic encapsulation layer, a second inorganic encapsulation layer and an organic encapsulation layer disposed between the first and second inorganic encapsulation layers, a through-hole arranged inside the display area to penetrate the substrate, an inner dam surrounding the through-hole, a trench arranged between the inner dam and the through-hole, and an etch-stopper arranged between the trench and the through-hole, wherein the first inorganic encapsulation layer and the second inorganic encapsulation layer are disposed on the display area and covering the inner dam and the trench.