LED Electron Blocking Layer Segmentation for Droop Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Light-emitting diodes (LEDs) face issues with lattice inconsistency between the light-emitting structure and the support substrate, leading to lattice defects and reduced luminous efficiency due to dislocations, which degrade the light-emission efficiency and cause a droop phenomenon as current density increases.
Innovation Solution
A light-emitting device with an electron blocking layer having multiple uneven portions and sub-layers with specific doping concentration peak sections, allowing for improved carrier implantation paths and enhanced light-emission efficiency by effectively implanting holes into the active layer, even with increased size of uneven portions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the light-emitting structure is provided on a support substrate, then the LED can operate at low voltage with high efficiency, but lattice inconsistency between the light-emitting structure and support substrate causes lattice defects and dislocations that degrade luminous efficiency
Solution Approach 1:
The electron blocking layer is divided into multiple sub-layers with different doping concentrations, creating a segmented structure that progressively manages carrier flow. This segmentation allows for optimized hole implantation at each interface while maintaining overall device efficiency, resolving the contradiction between energy efficiency and luminous efficiency by addressing the lattice defect issue through structured doping rather than uniform design
Solution Approach 2:
Different regions of the electron blocking layer are assigned different doping concentrations, with peak sections located at specific interfaces between sub-layers. This local quality variation enables targeted hole implantation at critical locations where lattice defects occur, improving luminous efficiency in problematic regions while maintaining low voltage operation and energy efficiency in other regions
2Productivity
If the size of uneven portions is increased to improve hole implantation, then carrier implantation efficiency improves, but the droop phenomenon worsens at high current density
Solution Approach 1:
The doping concentration parameter is varied across different sections of the electron blocking layer, with peak concentrations positioned at specific interfaces. This parameter change strategy enables effective hole implantation without requiring excessive uneven portion sizes, thereby improving carrier implantation efficiency while avoiding the droop phenomenon that occurs at high current densities with oversized structures
3Reliability
If multiple sub-layers with peak sections are formed in the electron blocking layer, then hole implantation into the active layer is improved, but the device complexity increases
Solution Approach 1:
The electron blocking layer is segmented into multiple sub-layers with doping peak sections at their interfaces. This segmentation approach systematically improves hole implantation efficiency by creating multiple doping peaks that guide carriers through the layer, while the modular nature of the segmentation makes the complexity manageable and the structure reproducible
Solution Approach 2:
The electron blocking layer is constructed as a composite structure with multiple sub-layers having different doping concentrations. This composite approach enables sophisticated carrier control and improved hole implantation efficiency, while the systematic composition of identical elements in different concentrations maintains manufacturing feasibility and does not excessively increase device complexity
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 solution enhances optical characteristics and light-emission efficiency, alleviating the droop phenomenon by improving hole implantation and reducing resistance, thereby maintaining light intensity and electrostatic discharge (ESD) performance.
Implementation Method 1
the electron blocking layer may have two or more doping concentration peak sections of a P-type dopant in a thickness direction of the electron blocking layer
Implementation Method 2
the electron blocking layer may have two or more peak sections in a thickness direction of the even region
Implementation Method 3
A light-emitting diode (LED) is one of light-emitting devices that emit light when a current is applied thereto
Data Source
AI summary
Disclosed in one embodiment is a light-emitting device comprising: a first semiconductor layer; an active layer arranged on the first semiconductor layer and including a plurality of first uneven portions; an electron blocking layer including a plurality of second uneven portions arranged on the plurality of first uneven portions; and a second semiconductor layer formed on the electron blocking layer, wherein the electron blocking layer has at least two doping concentration peak sections of a p-type dopant in the thickness direction.