Semiconductor LED with Rough Surface and Channel Layer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional semiconductor light emitting diodes using nitride semiconductors face inefficiencies in light extraction in the lateral direction, limiting their external light emitting efficiency.

Innovation Solution

The semiconductor light emitting diode is manufactured with a light emitting structure that includes forming roughness on its outer surface, a channel layer, and a second electrode layer, with mesa etching to expose the channel layer, enhancing light extraction angles and efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If conventional smooth outer surface is used in light emitting structure, then manufacturing process is simple, but light extraction angle in lateral direction is limited

Engineering Contradiction:
Improvelight extraction angleVSAvoidsurface structure complexity
Core Design Contradiction:
Illumination intensityVSDevice complexity

Solution Approach 1:

The patent applies surface curvature by forming roughness on the outer surface of the light emitting structure. This roughness creates curved and irregular surface features that scatter light in multiple directions, thereby improving the light extraction angle in the lateral direction compared to a conventional smooth planar surface.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Solution Approach 2:

The patent implements local quality by creating roughness specifically on the outer surface of the light emitting structure while maintaining other structural integrity. The roughness is localized to the surface region where light extraction occurs, allowing improved light extraction without fundamentally redesigning the entire device structure.

Inventive Principle:
Principle #3Local quality

2Productivity

If conventional light emitting structure without channel layer is used, then device structure is simpler, but external light emitting efficiency is limited

Engineering Contradiction:
Improveexternal light emitting efficiencyVSAvoidlayer structure complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent applies segmentation by introducing a channel layer that divides and separates the light emitting structure into distinct functional regions. The channel layer creates isolated light emitting regions or quantum wells that improve carrier confinement and recombination efficiency, thereby enhancing external light emitting efficiency through structural segmentation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The channel layer acts as an intermediary between the p-type and n-type semiconductor layers, providing a controlled interface for carrier injection and recombination. This intermediary layer facilitates efficient charge carrier transport and confinement, improving the overall light emission process without requiring complete restructuring of the device.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 approach improves light emitting efficiency in the lateral direction and external light extraction, enhancing the overall performance of the semiconductor light emitting diode.

Implementation Method 1

forming roughness on an outer surface of the light emitting structure... improve a light extraction angle of light emitted in a lateral direction

Methodology Applied
Scientific EffectLight scattering: Scattering

Data Source

PatentEP2219239B1Semiconductor light emitting diode
Publication Date: 2015.04.29 LG INNOTEK CO LTD
  • EP2219239B1 patent drawingFigure 1~2
  • EP2219239B1 patent drawingFigure 3~4
  • EP2219239B1 patent drawingFigure 5~6

AI summary

Disclosed is a semiconductor light emitting device (110). The semiconductor light emitting device includes a light emitting structure (110) including a first conductive semiconductor layer (111), an active layer (113) below the first conductive semiconductor layer, and a second conductive semiconductor layer below the active layer (115); a channel layer (120) below the light emitting structure, in which an inner portion of the channel layer is disposed along an outer peripheral portion (118) of the light emitting structure (110) and an outer portion of the channel layer extends out of the light emitting structure; and a second electrode layer (130) below the light emitting structure (110).