Anti-Contact Layer in Tandem OLED Charge Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In tandem organic light emitting display devices, the second electrode often comes into contact with the charge generation layer at the edges of the substrate, leading to uneven electric charge supply and accelerated degradation of the organic emissive layers, particularly at higher temperatures.
Innovation Solution
An anti-contact layer is introduced between the second electrode and the charge generation layer, completely surrounding the charge generation layer to prevent direct contact and ensure equal electric charge supply to both organic emissive layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the second electrode is extended to the edges of the substrate to supply electric charges, then electric charge supply capability is improved, but the electrode comes into contact with the charge generation layer causing uneven charge distribution and reduced device lifetime
Solution Approach 1:
An anti-contact layer is introduced as an intermediary between the second electrode and the charge generation layer. This layer prevents direct contact while allowing the electrode to extend to substrate edges, thereby maintaining charge supply capability without causing uneven charge distribution or device degradation.
2Ease of manufacture
If the second electrode contacts the charge generation layer at substrate edges, then electrode extension is simplified, but excessive electric charge supply to one organic emissive layer occurs causing accelerated degradation
Solution Approach 1:
The anti-contact layer serves as a mediator that allows the second electrode to extend to substrate edges for manufacturing simplicity while preventing excessive charge supply to the organic emissive layer, thereby maintaining layer stability and preventing accelerated degradation.
3Area of stationary object
If the second electrode is extended to substrate edges for charge supply, then charge supply coverage is improved, but contact with charge generation layer causes unbalanced charge distribution between organic emissive layers
Solution Approach 1:
The anti-contact layer acts as an intermediary that enables the second electrode to extend to substrate edges for comprehensive charge supply coverage while preventing direct contact with the charge generation layer, thereby ensuring uniform charge distribution between the first and second organic emissive layers.
Data Source
AI summary
An organic light emitting display device includes: a substrate including a display area having a plurality of pixel regions and a non-display area; a first electrode on the substrate; a first organic emissive layer on the first electrode; a charge generation layer on the first organic emissive layer as a common layer for the plurality of pixel regions; a second organic emissive layer on the charge generation layer; a second electrode on the second organic emissive layer as a common electrode for the plurality of pixel regions; and an anti-contact layer between the charge generation layer and the second electrode as a common layer for the plurality of pixel regions. The anti-contact layer completely surrounds the charge generation layer.