Group III-Nitride LED Current Spreading Layer with SiC
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Group III-nitride light emitting devices, such as LEDs and LDs, face challenges in enhancing output power and reducing operating voltage to prevent heat generation and improve reliability, while also requiring increased electrostatic discharge (ESD) resistance without the need for additional protective devices.
Innovation Solution
Incorporating a current spreading layer with a SiC layer between n-type clad layers, which includes high-concentration n-doped AlxGayIn1-x-yN layers and a SiC layer, enhancing current spreading and ESD resistance through the formation of a 2-dimensional electron gas layer and high dielectric constant properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional n-type clad layers are used in group III-nitride light emitting devices, then the device structure is simple, but the operating voltage is high and ESD resistance is insufficient
Solution Approach 1:
The patent combines ESD protection functionality and current spreading functionality into a single integrated layer structure. The SiC layer is merged with n-doped AlxGayIn1-x-yN layers to form a composite current spreading layer that simultaneously provides ESD protection and current spreading, eliminating the need for separate ESD protection devices and reducing structural complexity despite enhanced functionality
Solution Approach 2:
The patent uses composite material structure consisting of SiC layer combined with n-doped AlxGayIn1-x-yN layers. This composite current spreading layer leverages the high dielectric constant of SiC for ESD protection and the doped semiconductor properties of AlxGayIn1-x-yN for current spreading, achieving multiple functions through material composition
2Reliability
If operating voltage is not reduced, then device structure remains conventional, but heat generation increases and reliability decreases
Solution Approach 1:
The patent applies local quality by creating regions with different doping concentrations within the current spreading layer. The n-doped AlxGayIn1-x-yN layers have high electron concentration (1×10^19 to 1×10^21 cm^-3) to improve current spreading locally, while the SiC layer provides high dielectric constant regions for ESD protection, with each component optimized for its specific function to reduce overall operating voltage and heat generation
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 configuration reduces operating voltage, increases light emitting efficiency and output, and provides effective ESD protection, extending the useful life of the devices while simplifying manufacturing and reducing costs by eliminating the need for separate protective components.
Implementation Method 1
enhancing current spreading and ESD resistance through the formation of a 2-dimensional electron gas layer
Implementation Method 2
enhancing current spreading and ESD resistance through the formation of a 2-dimensional electron gas layer and high dielectric constant properties
Data Source
AI summary
The present invention provides a group III-nitride light emitting device improved in operating voltage and electrostatic discharge characteristics. The group III-nitride light emitting device comprises a lower n-type clad layer, a current spreading layer, an upper n-type clad layer, an active layer and an p-type clad layer formed in their order on a substrate. The current spreading layer includes a SiC layer.