Organic Electroluminescent Device Multi-Layer Passivation Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Active matrix type organic electroluminescent devices face limitations in preventing moisture and gas infiltration due to the use of ultraviolet sealants, which can lead to reliability issues and increased device thickness.
Innovation Solution
The formation of multiple passivation layers on a substrate where the organic electroluminescent layer is formed, including a first and second passivation layer, to isolate the light emitting diode and organic electroluminescent layer from external moisture and outgas, enhancing the device's reliability and allowing for improved seal line formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single seal line formed of ultraviolet sealant is used to attach substrates, then the device structure is simple, but moisture and gas can easily infiltrate into the device
Solution Approach 1:
The invention divides the sealing function into multiple segments: a first seal line and a second seal line are formed at different positions, creating a multi-layer sealing structure that prevents moisture and gas infiltration more effectively than a single seal line
Solution Approach 2:
The first seal line is formed before attaching the second substrate, creating a preliminary seal that prevents infiltration pathways. This preliminary sealing action enhances the overall reliability before final assembly is complete
2Reliability
If a moisture absorption agent is added inside the device to prevent infiltration, then moisture prevention is improved, but the device thickness increases
Solution Approach 1:
The invention extracts the moisture absorption function from the internal device structure and relocates it to the sealing layers. The seal lines themselves are designed to provide moisture barrier functionality, eliminating the need for separate internal moisture absorption agents and maintaining thin device profile
Solution Approach 2:
The seal lines serve multiple functions: they provide mechanical attachment between substrates, create sealing barriers against moisture and gas, and replace the need for separate moisture absorption agents. This multi-functionality reduces device thickness while maintaining reliability
3Manufacturing precision
If two substrates are attached with TFTs and organic electroluminescent layer, then active matrix type high resolution display is achieved, but moisture and gas infiltration increases due to single seal line
Solution Approach 1:
The sealing system is segmented into multiple independent seal lines at different positions, creating redundant barrier pathways that prevent moisture and gas from reaching the sensitive TFT and organic electroluminescent layer, thereby maintaining high reliability in high-resolution active matrix displays
Data Source
AI summary
An organic electroluminescent device and a method of fabricating the same are provided. The organic electroluminescent device includes a first substrate, a second substrate, a thin film transistor formed on the first substrate, a light emitting diode comprising first and second electrodes and an organic luminescent layer that are formed on the thin film transistor, and first and second passivation layers formed on the first substrate on which the light emitting diode is formed.