Micro-LED Chip Structure to Reduce Edge Surface Recombination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing micro-LED structures face challenges in enhancing light emission efficiency due to surface recombination carrier loss at the edges of the light emitting layer contacting the conductive layers.
Innovation Solution
A micro-LED structure is designed with a light emitting layer that extends horizontally away from the edges of the first and second conductive layers, preventing edge contact and reducing surface recombination, while also incorporating a metal layer on the light emitting layer between adjacent micro-LEDs for improved isolation and efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the light emitting layer contacts the conductive layers at the edges, then the device structure is simplified, but surface recombination carrier loss increases and light emission efficiency decreases
Solution Approach 1:
The light emitting layer is extended in the horizontal dimension away from the conductive layer edges, creating a dimensional offset that prevents edge contact. This horizontal extension into a new spatial zone eliminates the harmful edge contact while maintaining structural simplicity.
Solution Approach 2:
The extended horizontal portion of the light emitting layer acts as an intermediary zone between the conductive layers and the active light emission region. This intermediate structure prevents direct edge contact that would cause surface recombination, while still allowing proper carrier injection and light emission functionality.
2Loss of energy
If the light emitting layer extends horizontally away from the conductive layer edges, then light emission efficiency is improved by reducing surface recombination, but device complexity increases
Solution Approach 1:
The solution uses horizontal extension of the light emitting layer as a dimensional strategy to prevent edge contact. By utilizing the horizontal dimension rather than increasing vertical layering or complex 3D structures, the patent improves performance without proportionally increasing device complexity.
Solution Approach 2:
The light emitting layer has different functional zones: a horizontal extension zone that prevents surface recombination at edges, and a vertical active zone that performs light emission. This local differentiation of quality and function within the same layer achieves performance improvement without requiring entirely new complex structures.
3Productivity
If adjacent micro-LEDs are placed close together, then device integration density is improved, but carrier leakage between adjacent devices increases
Solution Approach 1:
The extended horizontal portion of the light emitting layer serves as an intermediary isolation zone between adjacent micro-LEDs. This intermediate structure prevents direct carrier leakage pathways between neighboring devices while maintaining close spacing for high integration density.
Solution Approach 2:
The continuous light emitting layer is effectively segmented into discrete functional regions for each micro-LED by the horizontal extension that creates isolation zones. This segmentation prevents carrier leakage between adjacent devices while maintaining the overall integrated structure.
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 enhances light emission efficiency by minimizing surface recombination and improving carrier injection efficiency, while the metal layer aids in isolating adjacent micro-LEDs, leading to improved performance and reliability.
Implementation Method 1
A micro-light emitting diode (micro-LED) is a device that emits light using an electric signal
Data Source
AI summary
A micro-LED chip includes multiple micro-LEDs. At least one micro-LED of the multiple micro-LEDs includes: a first type conductive layer; a second type conductive layer stacked on the first type conductive layer; and a light emitting layer formed between the first type conductive layer and the second type conductive layer. The light emitting layer is continuously formed on the whole micro-LED chip, the multiple micro-LEDs sharing the light emitting layer. An isolation structure is formed between adjacent micro-LEDs, at least a portion of the isolation structure being formed in the light emitting layer. A top surface of the isolation structure is above the light emitting layer, and a bottom surface of the isolation structure is under the light emitting layer.