OLED Common Voltage Line Protection Against Etching Damage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The common voltage line in OLED displays is exposed to etching processes, leading to potential damage and cracks in the encapsulation member, which can result in moisture permeation and out-gassing issues.
Innovation Solution
A protection member is formed to cover the side wall of the common voltage line, preventing exposure and damage during etching processes, and ensuring a smooth encapsulation layer formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the common voltage line is exposed to etching processes for forming the encapsulation member, then the encapsulation member can be formed to protect the pixel unit, but the side wall of the common voltage line may be etched or damaged leading to cracks in the encapsulation member
Solution Approach 1:
A protection member is formed over the common voltage line before the etching process to prevent etching damage. This preliminary protective action ensures the common voltage line is shielded from harmful etching effects while still allowing the encapsulation member to be formed subsequently.
Solution Approach 2:
The protection member acts as an intermediary between the common voltage line and the etching process. It provides a physical barrier that prevents direct contact between the etching chemicals and the common voltage line, thereby eliminating etching damage while allowing the encapsulation process to proceed.
2Ease of manufacture
If the common voltage line is exposed during etching, then the encapsulation member formation process can proceed, but moisture permeation and out-gassing functions are deteriorated
Solution Approach 1:
The protection member is formed in advance to prevent damage to the common voltage line before encapsulation. This ensures that the voltage line remains intact and functional, maintaining its moisture barrier properties while still allowing the encapsulation process to be easily performed.
Solution Approach 2:
The protection member, while adding a step to the manufacturing process, actually prevents the harmful effect of etching damage. By converting the potential harm of exposed voltage lines into a protected state, it ensures long-term reliability and moisture barrier function of the encapsulated structure.
3Reliability
If a protection member is formed to cover the common voltage line, then damage during etching is prevented, but the device structure becomes more complex
Solution Approach 1:
The protection member is selectively formed only where needed - specifically over the common voltage line - rather than covering the entire device uniformly. This localized approach provides necessary protection while minimizing the overall structural complexity and material usage.
Solution Approach 2:
The protection member serves as a temporary, disposable element that is formed for the specific purpose of protecting the common voltage line during manufacturing, and is subsequently removed or integrated into the final structure. This approach adds minimal permanent complexity while achieving the protection goal.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An organic light emitting diode (OLED) display includes a substrate including a pixel area and a peripheral area surrounding the pixel area. The pixel area includes at least one pixel including an organic light emitting element. The OLED display further includes a common voltage line disposed in the peripheral area and configured to transmit a common voltage to the pixel area, a barrier rib disposed on the substrate and covering one side of the common voltage line, a protection member covering another side of the common voltage line, at least one thin film transistor disposed in the pixel area, a first electrode disposed in the pixel area and connected to the at least one thin film transistor, an organic emission layer disposed on the first electrode, and a second electrode disposed on the organic emission layer and connected to the common voltage line.