LED Epitaxy Structure With Alternating Doping for Uniform Current Spreading

Solution Overview

Problem

Conventional light emitting diodes (LEDs) suffer from poor current spreading, leading to decreased luminous efficiency, uneven illumination, and color variation.

Innovation Solution

The proposed LED structure incorporates a semiconductor epitaxy structure with a substrate, featuring a semiconductor composite layer and multiple current spreading layers with alternating high and low doping concentrations, and varying thicknesses to ensure uniform current distribution.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If conventional LED structure is used, then device simplicity is maintained, but current spreading is poor leading to uneven illumination and color variation

Engineering Contradiction:

Improveuniformity of illuminationVSAvoidstructure complexity

Core Design Contradiction:

Illumination intensityVSDevice complexity

Solution Approach 1:

The semiconductor composite layer is segmented into multiple current spreading layers with alternating high and low doping concentrations. This segmentation creates distinct regions that guide current flow patterns, forcing current to spread uniformly across the emission region rather than concentrating in specific areas, thereby resolving the uneven illumination problem while maintaining reasonable structural complexity

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the semiconductor composite layer are assigned different doping concentrations (high and low alternating patterns) to create localized electrical properties. This local quality variation ensures that current spreads uniformly across different areas of the LED, preventing color variation and achieving consistent illumination intensity throughout the device

Inventive Principle:

Principle #3Local quality

2Loss of energy

If current spreading layers with alternating doping concentrations are added, then luminous efficiency is improved, but manufacturing complexity increases

Engineering Contradiction:

Improveluminous efficiencyVSAvoidmanufacturing process complexity

Core Design Contradiction:

Loss of energyVSEase of manufacture

Solution Approach 1:

The semiconductor composite layer is divided into multiple current spreading layers with alternating high and low doping concentrations. This segmentation creates distinct regions that guide current flow patterns, forcing current to spread uniformly across the emission region rather than concentrating in specific areas, thereby resolving the uneven illumination problem while maintaining reasonable structural complexity

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The doping concentration parameter is systematically varied across different layers of the semiconductor composite structure. By alternating between high and low doping concentrations in a controlled manner, the invention optimizes current spreading characteristics and enhances carrier recombination efficiency, directly improving luminous efficiency through parameter optimization

Inventive Principle:

Principle #35Parameter changes

3Stability of the object's composition

If multiple current spreading layers are implemented, then color consistency is improved, but device complexity increases

Engineering Contradiction:

Improvecolor consistencyVSAvoidlayer structure complexity

Core Design Contradiction:

Stability of the object's compositionVSDevice complexity

Solution Approach 1:

Different regions of the semiconductor composite layer are assigned different doping concentrations (high and low alternating patterns) to create localized electrical properties. This local quality variation ensures that current spreads uniformly across different areas of the LED, preventing color variation and achieving consistent illumination intensity throughout the device

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The semiconductor composite layer is segmented into multiple current spreading layers with alternating high and low doping concentrations. This segmentation creates distinct regions that guide current flow patterns, forcing current to spread uniformly across the emission region rather than concentrating in specific areas, thereby resolving the uneven illumination problem while maintaining reasonable structural complexity

Inventive Principle:

Principle #1Segmentation

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 design enhances the brightness of LEDs by achieving uniform current spreading, thereby improving luminous efficiency and maintaining consistent illumination and color across the LED surface.

Implementation Method 1

Current spreading allows these charge carriers to move from high concentration areas to low concentration areas, achieving effective carrier injection

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Implementation Method 2

When electrons and holes are injected into the P-N junction region, they undergo recombination within this region to release energy and generate the light emitted by the LEDs

Methodology Applied

Scientific EffectElectroluminescence: Electroluminescence

Data Source

PatentEP4531119A1Light emitting diode

Publication Date: 2025.04.02 TAIWAN ASIA SEMICONDUCTOR CORPORATION

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AI summary

The invention relates to a light emitting diode, which comprises a substrate and a semiconductor epitaxy structure. The semiconductor epitaxial structure is disposed on the substrate. The semiconductor epitaxial structure comprises semiconductor composite layers and a plurality of current spreading layers which are disposed among the semiconductor composite layers. The doping concentrations of the upper and lower adjacent current spreading layers are alternately high and low.