Light Emitting Device Via Electrode Active Area
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lateral-type light emitting devices face issues with light loss and reliability due to mesa etching and increased operating voltage, as well as degraded light extraction efficiency caused by electrode absorption.
Innovation Solution
A light emitting device design featuring a substrate with a first and second conductive semiconductor layer, an active layer, a contact layer, and insulating layer, along with branch electrodes and via electrodes that pass through the insulating layer to secure a wider active layer area and reduce operating voltage, improving light extraction efficiency and reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If mesa etching is performed to form electrodes on the nitride semiconductor layer, then the active layer area is reduced, but light loss is caused at the active layer
Solution Approach 1:
The patent transitions from a planar electrode configuration to a three-dimensional via electrode structure that penetrates through the insulating layer. This vertical dimension allows electrodes to contact the nitride semiconductor layer at multiple points without occupying excessive horizontal active layer area, thereby reducing light loss while maintaining electrical connectivity.
Solution Approach 2:
The patent introduces an insulating layer as an intermediary between the electrode and the nitride semiconductor layer. This insulating layer with controlled thickness and dielectric properties enables electrical connection through via electrodes while preventing direct contact that would cause light absorption, thus resolving the contradiction between electrical connectivity and light extraction efficiency.
2Area of moving object
If a through-electrode type is used to partially connect the electrode to the nitride semiconductor layer, then the removed area of active area is reduced, but operating voltage increases
Solution Approach 1:
The patent divides the electrode structure into multiple segments: a planar electrode layer, an insulating layer, and multiple via electrodes distributed across the surface. This segmentation allows the electrical connection to be distributed across multiple small contact points rather than one large contact, reducing the operating voltage while maintaining a wide active layer area.
Solution Approach 2:
The patent adds the vertical dimension by creating via electrodes that penetrate through the insulating layer to contact the nitride semiconductor layer. This three-dimensional configuration reduces the horizontal footprint of electrodes, preserving active layer area while providing multiple low-resistance contact paths that reduce operating voltage.
3Reliability
If an electrode layer is disposed on the nitride semiconductor layer, then electrical connection is achieved, but light extraction efficiency is degraded due to light absorption
Solution Approach 1:
The patent introduces an insulating layer as an intermediary between the electrode and the nitride semiconductor layer. This insulating layer with controlled thickness and dielectric properties enables electrical connection through via electrodes while preventing direct contact that would cause light absorption, thus resolving the contradiction between electrical connectivity and light extraction efficiency.
Solution Approach 2:
The patent applies different properties to different regions: the insulating layer provides electrical isolation in most areas while allowing localized electrical connection through via electrodes. The electrode structure has local conductivity where needed (at via contacts) and local insulation where light extraction is critical, optimizing both electrical connection and light extraction efficiency.
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 enhances light efficiency and reliability by minimizing center current crowding and reducing operating voltage, resulting in increased light intensity and wall-plug efficiency.
Implementation Method 1
A light emitting device (LED) includes a p-n junction diode having a characteristic of converting electric energy into light energy
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Disclosed are a light emitting device, a method of manufacturing a light emitting device, a light emitting device package and a lighting system. The light emitting device a substrate comprises a first conductive semiconductor layer on the substrate; an active layer on the first conductive semiconductor layer; a second conductive semiconductor layer on the active layer; a contact layer on the second conductive semiconductor layer; an insulating layer on the contact layer; a first branch electrode electrically connected to the first conductive semiconductor layer; a plurality of first via electrodes connected to the first branch electrode and electrically connected to the first conductive semiconductor layer by passing through the insulating layer; a first pad electrode electrically connected to the first branch electrode; a second pad electrode contacts the contact layer by passing through the insulating layer; a second branch electrode connected to the second pad electrode and disposed on the insulating layer; and a plurality of second via electrodes provided through the insulating layer to electrically connect the second branch electrode to the contact layer.