Light-Emitting Element Structure With Bragg Reflector for Afterimage Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current light-emitting elements in display devices face challenges in enhancing optical efficiency and minimizing momentary afterimages, primarily due to limitations in the design of semiconductor layers and reflective structures.
Innovation Solution
The proposed solution involves a light-emitting element configuration with a multilayer insulating film surrounding the semiconductor and reflective layers, where the insulating film is formed as a multilayer film and the reflective layer is designed as a distributed Bragg reflector, alternately stacking layers with different refractive indices to improve light reflection and quantum efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional single-layer insulating film and simple reflective layer are used, then the device structure is simple, but the quantum efficiency is low and momentary afterimages occur
Solution Approach 1:
The insulating film is divided into multiple layers (first insulating film, second insulating film, third insulating film) with different refractive indices, where each layer serves a specific optical function to improve light extraction efficiency and reduce momentary afterimages while maintaining manageable device complexity
Solution Approach 2:
The reflective layer is designed as a distributed Bragg reflector comprising alternating layers of high refractive index material (e.g., TiO2, Ta2O5) and low refractive index material (e.g., SiO2, SiNx), creating a composite structure that achieves high reflectivity across a broad wavelength range, thereby improving quantum efficiency
2Reliability
If a distributed Bragg reflector with alternating refractive indices is used, then light reflection efficiency is improved, but the manufacturing process becomes more complex
Solution Approach 1:
The distributed Bragg reflector is designed with specific thickness parameters for each layer (typically λ/4 optical thickness) and controlled refractive index ratios, allowing optimization of reflection efficiency across different wavelengths while maintaining compatibility with existing semiconductor fabrication processes
Solution Approach 2:
The alternating high and low refractive index layers act as optical intermediaries that progressively build up reflectivity through multiple interfaces, enabling high light reflection efficiency without requiring single-layer materials with extremely high reflectivity that would be difficult to manufacture
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 the quantum efficiency and reduces momentary afterimages, leading to improved light output efficiency and optical performance of the light-emitting elements.
Implementation Method 1
the reflective layer is designed as a distributed Bragg reflector, alternately stacking layers with different refractive indices to improve light reflection
Implementation Method 2
alternately stacking layers with different refractive indices
Implementation Method 3
a light-emitting layer disposed on the first semiconductor layer
Data Source
AI summary
A light-emitting element includes a first semiconductor layer, a light-emitting layer disposed on the first semiconductor layer, a second semiconductor layer disposed on the light-emitting layer, a device electrode layer disposed on the second semiconductor layer, a reflective electrode layer disposed on the device electrode layer, an insulating film surrounding a side surface of the light-emitting layer, a side surface of the second semiconductor layer, and a side surface of the device electrode layer, and a reflective layer surrounding a side surface of the insulating film, wherein the side surface of the device electrode layer is aligned with a side surface of the reflective electrode layer.