Organic EL Anode Adhesion via Partition Wall Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The conventional top emission type active matrix organic electroluminescent devices face issues with anode electrode peeling due to low adhesion with the flattening insulation layer, leading to device reliability concerns and increased resistance in the transparent cathode electrode.
Innovation Solution
The solution involves forming a partition wall with an overhang structure to separate anode electrodes and using the anode electrode material as a subsidiary electrode, which enhances adhesion and reduces the risk of peeling, while also improving the cathode electrode's conductivity by forming it directly on the anode electrode material.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a conventional top emission type active matrix organic EL device is manufactured with a flattening insulation layer, then the manufacturing process can be simplified, but the anode electrode peels off due to low adhesion
Solution Approach 1:
The patent divides the originally single flattening insulation layer into two separate insulation layers: a first insulation layer formed before the anode electrode, and a second insulation layer formed after the anode electrode. This segmentation allows each layer to serve its specific function - the first layer provides a stable base for electrode formation while the second layer provides planarization for subsequent processing, thereby resolving the adhesion problem while maintaining manufacturing simplicity.
Solution Approach 2:
The first insulation layer acts as an intermediary between the substrate and the anode electrode, providing a surface that ensures proper adhesion. By introducing this intermediate layer with specific material properties, the patent enables reliable electrode attachment without compromising the overall manufacturing process.
2Illumination intensity
If the transparent cathode electrode is made thinner to improve transparency, then light emission is enhanced, but the resistance increases
Solution Approach 1:
The patent employs composite material structures for the cathode electrode, combining transparent conductive oxide layers with metallic layers. This composite approach allows the electrode to maintain both high transparency (from the thin oxide layer) and low resistance (from the metallic component), resolving the contradiction between optical performance and electrical performance.
3Illumination intensity
If the aperture ratio is increased to improve display brightness, then more light is emitted, but the TFT size must be reduced which complicates manufacturing
Solution Approach 1:
The patent transitions from a bottom-emission architecture to a top-emission architecture, changing the dimensional direction of light output. This dimensional change allows light to be emitted from the top surface, enabling the aperture ratio to be determined by the pixel structure rather than being constrained by TFT size, thereby decoupling brightness from TFT dimensions and simplifying manufacturing.
Data Source
Figure 1A~1B
Figure 1C~1D
Figure 1E~1F
AI summary
An organic electroluminescent device, adapted to enhance device reliability while allowing simplification of a manufacturing process, and a method for manufacturing the same are disclosed. The organic electroluminescent (EL) device, comprising a substrate (31), TFTs (32) located in respective unit pixel regions on the substrate (31), a first insulation layer (33) to insulate the TFTs (32), first electrodes (39) formed on the first insulation layer (33) while contacting the TFTs (32), respectively, a partition wall (38) positioned between the unit pixel regions on the first insulation layer (33), a subsidiary electrode (39) formed on the partition wall (38), an organic light emitting layer (43) positioned on the first electrodes (39), an insulation part (40) to insulate each first electrode (39) from an associated subsidiary electrode (39), and a second electrode (44) positioned on the organic light emitting layer (43) and connected with the subsidiary electrode (39).