LED Light Extraction via Recessed Window Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current light-emitting diodes (LEDs) face challenges in enhancing light-emitting efficiency, which is crucial for their widespread application in various devices due to limitations in power consumption, heat generation, and optical properties.
Innovation Solution
A light-emitting device design featuring a semiconductor window layer with recesses, where the side wall surface is inclined, and an ohmic contact layer formed between the semiconductor window layer and the transparent conductive layer, optimizing contact resistance and light extraction efficiency by directing emitted light to escape through the flat surface.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If recesses are added to the semiconductor window layer, then light extraction efficiency is improved, but device structure complexity increases
Solution Approach 1:
The semiconductor window layer is segmented into multiple recesses with different depths and configurations. This segmentation creates multiple light extraction pathways and interfaces, thereby improving light extraction efficiency while maintaining a manageable structural complexity through systematic design of the recess patterns.
Solution Approach 2:
The invention introduces vertical dimensionality by creating recesses at different depths within the semiconductor window layer. This multi-level recess structure adds a depth dimension to the previously planar surface, enabling enhanced light extraction through multiple interfaces without requiring excessive lateral complexity.
2Productivity
If the side wall surface is made inclined, then light extraction is enhanced, but manufacturing precision requirements increase
Solution Approach 1:
The invention optimizes the inclination angle of the side wall surfaces as a key parameter to balance light extraction enhancement with manufacturing feasibility. By selecting specific inclination angles that provide sufficient optical improvement while remaining within standard fabrication capabilities, the design achieves enhanced performance without excessively stringent precision requirements.
3Reliability
If contact resistance is reduced at the flat surface, then electrical performance is improved, but light extraction pathways are reduced
Solution Approach 1:
The invention applies different qualities to different regions: the flat surface area is optimized for low contact resistance to ensure excellent electrical performance, while the recess structures provide dedicated light extraction pathways. This local differentiation allows simultaneous optimization of both electrical and optical functions without compromise.
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
The design significantly improves luminous intensity by reducing contact resistance and enhancing light extraction, resulting in increased light-emitting efficiency compared to traditional LED structures without recesses.
Implementation Method 1
The side wall surface of one of the recesses is inclined with respect to the flat surface... directing emitted light to escape through the flat surface
Implementation Method 2
an ohmic contact layer formed between the semiconductor window layer and the transparent conductive layer, optimizing contact resistance
Data Source
AI summary
This disclosure discloses a light-emitting device. The light-emitting device comprises: a substrate; and a first light-emitting unit comprising a plurality of light-emitting diodes electrically connected to each other on the substrate. A first light-emitting diode in the first light-emitting unit comprises a first semiconductor layer with a first conductivity-type, a second semiconductor layer with a second conductivity-type, and a light-emitting stack formed between the first and second semiconductor layers. The first light-emitting diode in the first light-emitting unit further comprises a first connecting layer on the first semiconductor layer for electrically connecting to a second light-emitting diode in the first light-emitting unit; a second connecting layer, separated from the first connecting layer, formed on the first semiconductor layer; and a third connecting layer on the second semiconductor layer for electrically connecting to a third light-emitting diode in the first light-emitting unit.