Organic Light-Emitting Display Partition Wall Moisture Barrier
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing organic light-emitting display devices face issues with moisture permeation through insulating layers supporting partition walls, which can lead to degradation of the organic light-emitting layer, and insufficient contact area between the upper and auxiliary electrodes.
Innovation Solution
The design includes a first bank insulating layer with holes exposing the lower and auxiliary electrodes, a second bank insulating layer with a partition wall overlapping it, and a positively tapered surface to ensure the upper electrode connects directly to the auxiliary electrode while preventing moisture ingress, using a protective layer to further shield the organic light-emitting layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a partition wall is used to prevent organic light-emitting layer deposition on the auxiliary electrode, then the contact area between upper electrode and auxiliary electrode is improved, but moisture can permeate through the insulating layer supporting the partition wall
Solution Approach 1:
The insulating layer is divided into multiple segments: a first insulating layer supporting the partition wall, and a second insulating layer extending from the first insulating layer to cover the step. This segmentation allows the partition wall to maintain contact area while the second insulating layer blocks moisture permeation paths through the step.
Solution Approach 2:
The insulating layer structure is extended into a third dimension by creating a step with a first insulating layer and a second insulating layer at different levels. The partition wall is positioned on the first insulating layer while the second insulating layer covers the step, creating a multi-level moisture barrier that prevents lateral moisture permeation while maintaining electrical contact.
2Ease of manufacture
If the upper electrode and protective layer are not deposited on the insulating layer supporting the partition wall, then the partition wall can support the structure, but a path for external moisture to permeate to the organic light-emitting layer is created
Solution Approach 1:
The first insulating layer is formed beforehand to provide a support surface for the partition wall before the upper electrode and protective layer are deposited. This preliminary insulating layer prevents moisture permeation from the substrate side while allowing subsequent layers to be deposited without requiring complete coverage of the insulating layer surface.
Solution Approach 2:
The second insulating layer acts as an intermediary moisture barrier between the first insulating layer and the external environment. It extends from the first insulating layer to cover the step, blocking moisture permeation paths while allowing the upper electrode and protective layer to be deposited only where needed for electrical contact.
3Object-affected harmful factors
If a second bank insulating layer is spaced apart from the first bank insulating layer, then moisture permeation is prevented, but the contact area between upper electrode and auxiliary electrode may be reduced
Solution Approach 1:
The second insulating layer is positioned locally to cover only the step region where moisture permeation is most likely to occur. It is spaced apart from the first insulating layer only where needed to block moisture paths, while leaving other areas open to maintain electrical contact between the upper electrode and auxiliary electrode through the partition wall.
Solution Approach 2:
The spaced-apart configuration of the first and second insulating layers creates a three-dimensional moisture barrier structure. The vertical spacing and lateral extension of the second insulating layer over the step provide moisture protection without completely enclosing the auxiliary electrode, allowing electrical contact to be maintained through the partition wall while blocking moisture permeation paths.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An organic light-emitting display device including a partition wall is provided. The organic light-emitting display device includes a first bank insulating layer covering an edge of a lower electrode and a second bank insulating layer supporting the partition wall. The second bank insulating layer is completely spaced apart from the first bank insulating layer. The first bank insulating layer facing the second bank insulating layer is completely covered by an upper electrode which is disposed on a portion of the lower electrode exposed by the first bank insulating layer.