AlO Layer Prevents Peeling on Organic Passivation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In organic EL and liquid crystal display devices, the moisture content in organic passivation layers, such as polyimide, leads to gas release during baking processes, causing conduction or insulation failures due to peeling off of metal or insulating layers from the passivation film.
Innovation Solution
The implementation of an AlO layer over the organic passivation layer, along with additional AlO layers and gas exhaust holes in the electrode layers, helps to prevent peeling by controlling moisture and gas release, ensuring stable layer adhesion during high-temperature processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If an organic passivation layer (e.g., polyimide) is used to flatten the pixel portion, then the mechanical strength and heat resistance are improved, but moisture content increases causing gas release during baking
Solution Approach 1:
A resin layer is introduced as an intermediary between the organic passivation layer and the upper layers (electrode or insulating layers). This resin layer acts as a buffer that absorbs or accommodates the gas released from the organic passivation layer during baking, preventing the gas from directly causing peeling between the organic passivation layer and the upper layers.
2Stability of the object's composition
If the organic passivation layer contains moisture, then the material properties are maintained, but peeling occurs during baking process
Solution Approach 1:
The resin layer is formed in advance before the electrode or insulating layers are deposited on the organic passivation layer. This preliminary action ensures that when gas is released during subsequent baking processes, the resin layer is already in position to prevent peeling, thereby maintaining layer adhesion reliability without requiring removal of moisture from the organic passivation layer.
3Object-generated harmful factors
If high-temperature baking is applied to remove moisture, then gas release is reduced, but layer peeling occurs due to thermal stress
Solution Approach 1:
The resin layer serves as a cushioning layer that is positioned beforehand between the organic passivation layer and the upper layers. During high-temperature baking, this cushioning layer absorbs the thermal stress and gas pressure, preventing direct stress transmission that would cause peeling between the organic passivation layer and the electrode or insulating layers.
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 solution effectively prevents the peeling off of conductive or insulating layers from the organic passivation layer, maintaining electrical integrity and insulation by thoroughly degassing and protecting against reabsorption of moisture, thus enhancing the reliability of display devices.
Implementation Method 1
wherein the organic passivation layer is prevented from reabsorbing moisture by an AlO layer
Implementation Method 2
it releases gasses in a baking process in a post process
Data Source
AI summary
An organic EL display device has a semiconductor circuit substrate comprising a TFT and an organic passivation layer thereon. An AlO layer is formed over the organic passivation layer, and an electrode layer is formed on the AlO layer. The electrode layer connects with TFT via a through hole formed in the AlO layer and in the organic passivation layer.