OLED Anode Fence Structure for Lateral Leakage Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
OLED panels face lateral leakage current issues due to continuous organic multilayers, leading to reduced signal voltage amplitude, image blurring, and decreased color gamut, especially when voltage differences exist between adjacent sub-pixels, and existing solutions complicate manufacturing with low repeatability and reproducibility.
Innovation Solution
The OLED panel incorporates a fence structure with a trench between the sidewall of the fence and the pixel definition layer, utilizing a shadowing effect to discontinue the first charge transport layer, thereby minimizing lateral leakage current, and includes a ring-shaped fence structure with notches to ensure continuity and conductivity, simplifying the manufacturing process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a pixel definition layer is used to achieve physical separation of adjacent sub-pixels, then manufacturing complexity is reduced, but lateral leakage current occurs between adjacent sub-pixels
Solution Approach 1:
The patent introduces a fence structure that divides the pixel definition layer into multiple segments (first pixel definition layer and second pixel definition layer separated by a trench). This segmentation interrupts the continuous charge transport layer, blocking lateral leakage current paths while maintaining the overall pixel definition function. The segmented approach resolves the contradiction by preserving manufacturing simplicity while eliminating the harmful lateral leakage effect.
Solution Approach 2:
The fence structure acts as an intermediary element between adjacent sub-pixels. It includes a conductive layer connected to the anode and a pixel definition layer with a trench, serving as a mediator that provides electrical connection while physically blocking the continuous path for lateral leakage current. This intermediary structure resolves the contradiction by maintaining ease of manufacture while preventing the harmful effect.
2Productivity
If the organic multilayer is continuously deposited without shadow mask, then manufacturing productivity is improved, but lateral leakage current reduces signal voltage amplitude
Solution Approach 1:
The fence structure segments the pixel definition layer and charge transport layer, creating discrete regions that prevent lateral leakage current. This segmentation allows continuous deposition without shadow masks while maintaining signal integrity, as the fenced regions isolate adjacent sub-pixels and prevent current leakage that would reduce signal voltage amplitude.
Solution Approach 2:
The patent extracts the harmful lateral leakage current path by removing the continuous connection between adjacent sub-pixels through the trench in the pixel definition layer. This extraction maintains the benefits of continuous deposition for productivity while eliminating the harmful effect on signal voltage amplitude through the isolated fenced regions.
3Manufacturing precision
If lateral leakage current is blocked by discontinuing the charge transport layer, then display resolution is improved, but manufacturing complexity increases
Solution Approach 1:
The fence structure serves as an intermediary that achieves precise pixel isolation without requiring complex discontinuous charge transport layer deposition. The mediator structure (fence with conductive layer and pixel definition layer) provides a straightforward manufacturing approach that improves display resolution by blocking lateral leakage while avoiding the complexity of precise continuous layer interruption.
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 configuration effectively reduces lateral leakage current, enhancing display resolution and color gamut while improving the reliability and reproducibility of OLED panel performance by discontinuing the charge transport layer and maintaining conductivity, thus simplifying the manufacturing process.
Implementation Method 1
As a trench is formed between a sidewall of the fence structure and a sidewall of the opening area prior to the evaporation of the OLED multilayer, then the evaporated first charge transport layer may be discontinued in the trench, resulting from a shadowing effect of the fence structure.
Data Source
AI summary
An OLED panel includes a plurality of light-emitting elements, that each light-emitting element includes a fence structure on a substrate and in an opening of a pixel definition layer. A trench is formed between the fence structure and the pixel definition layer. Charge transport layer is disconnected at the trench by a shadowing effect of the fence structure during thermal evaporation of the charge transport layer. Therefore, lateral current leakage between two adjacent light-emitting elements is minimized.