Top-Emitting OLED Cathode IR Drop Reduction via Conductive Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The top-emitting IJP OLED structure faces issues with severe voltage drop due to higher resistance in the thinner cathode material, leading to uneven brightness and a short operating life, along with image sticking problems.
Innovation Solution
An organic electroluminescent diode device with a conductive layer between the first electrode and electron injection layer, an inverted structure with additional layers such as electron and hole transport layers, and a light-coupling layer, fabricated using techniques like inkjet printing and sputtering, to enhance electron injection and reduce IR drop effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a top-emitting IJP OLED structure is used with a thinner cathode material, then the device achieves active light emission and high color reality, but the panel experiences severe voltage drop and uneven brightness
Solution Approach 1:
An electron injection layer is introduced as an intermediary between the cathode and the light-emitting layer. This layer facilitates electron injection into the light-emitting layer, allowing the cathode to be thinner while maintaining effective electron supply, thus resolving the contradiction between thin cathode design and brightness uniformity
Solution Approach 2:
The original cathode structure is segmented into a conductive layer and a separate electron injection layer. The conductive layer provides electrical connection while the electron injection layer specifically handles electron injection into the light-emitting layer, improving electron injection efficiency and reducing IR drop effects
2Length of moving object
If the cathode material is made thinner to achieve top-emitting structure, then the device becomes lighter and thinner, but the resistance increases causing severe IR drop
Solution Approach 1:
The electron injection layer acts as a mediator that compensates for the high resistance of the thin cathode by providing an efficient electron injection pathway directly into the light-emitting layer, reducing the impact of IR drop
Solution Approach 2:
The energy level parameters of the electron injection layer are specifically designed to match between the cathode and light-emitting layer, creating favorable energy level alignment that enhances electron injection efficiency and reduces voltage drop
3Reliability
If additional layers (electron injection layer, transport layers) are added to improve electron injection, then electron injection efficiency increases, but the device structure becomes more complex
Solution Approach 1:
The electron injection layer is designed with multi-functionality: it serves as both an electron injection interface and an electron transport pathway. The transport layers similarly perform multiple functions including charge transport and energy level matching, reducing the need for additional specialized 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 configuration effectively reduces electron injection gaps, prevents image sticking, and ensures uniform brightness by minimizing the impact of IR drop, thereby extending the panel's operating life and maintaining consistent display quality.
Implementation Method 1
effectively reduce a potential gap between the first electrode layer and the electron injection layer by adding a conductive layer between a first electrode layer and an electron injection layer, thereby increasing an effect of electron injection
Implementation Method 2
a light-emitting layer (150), wherein the light-emitting layer is disposed on the electron injection layer
Data Source
AI summary
The present invention provides an organic electroluminescent diode device, a display panel, and a manufacturing method thereof. The organic electroluminescent diode device includes a first electrode layer, a conductive layer, an electron injection layer, a light-emitting layer, a hole injection layer, and a second electrode layer, and the conductive layer is provided between the first electrode layer and the electron injection layer.