Oriented Alumina Substrate Grain Control for Epitaxial Growth
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor devices, such as light-emitting devices, face limitations in properties due to the characteristics of sapphire substrates, which are expensive and have size constraints, necessitating the development of alternative substrates like oriented alumina for improved epitaxial growth.
Innovation Solution
The use of oriented alumina substrates with crystalline grains having a tilt angle of 0.1° to 1.0° and an average sintered grain size of 10 μm or more, optimized through specific production methods involving multilayer body formation and sintering, to enhance the properties of semiconductor devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If sapphire substrates are used for epitaxial growth, then good device properties are achieved, but the substrate area is limited and cost is high
Solution Approach 1:
The patent replaces expensive sapphire substrates with oriented alumina substrates that can be mass-produced at lower cost. The alumina substrates serve as temporary growth substrates during epitaxial growth, enabling cost-effective production while maintaining device performance through controlled crystalline grain characteristics.
Solution Approach 2:
The patent changes the substrate material from sapphire to oriented alumina and controls specific parameters including tilt angle (0.1° to 1.0°) and average sintered grain size (10 μm or more) to achieve both large area and good device properties, resolving the contradiction between substrate area and device quality.
2Reliability
If sapphire substrates are used for epitaxial growth, then good device properties are achieved, but the substrate cost is high
Solution Approach 1:
The patent substitutes costly sapphire substrates with inexpensive oriented alumina substrates that can be manufactured at scale. These alumina substrates fulfill their function as growth templates during epitaxial growth and can be removed, providing a cost-effective solution that maintains device performance.
Solution Approach 2:
The patent changes the substrate material composition from sapphire to oriented alumina and optimizes microstructural parameters (tilt angle and grain size) to achieve low-cost manufacturing while preserving the epitaxial growth quality and resulting device properties.
3Use of energy by moving object
If oriented alumina substrates with large grain size are used, then light extraction efficiency is improved, but manufacturing complexity increases
Solution Approach 1:
The patent optimizes specific parameters of the oriented alumina substrate including tilt angle (0.1° to 1.0°) and average sintered grain size (10 μm or more) to enhance light extraction efficiency. These controlled parameter changes achieve improved optical performance while maintaining manufacturability through standardized production processes.
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 results in semiconductor devices with improved light extraction efficiency and optical transparency, leading to enhanced performance in devices like light-emitting diodes and solar cells, while also addressing the cost and size limitations of sapphire substrates.
Implementation Method 1
the slight tilt of semiconductor grains constituting the functional layer for the emission of light results in improved light extraction efficiency
Data Source
AI summary
An oriented alumina substrate for epitaxial growth according to an embodiment of the present invention includes crystalline grains constituting a surface thereof, the crystalline grains having a tilt angle of 0.1° or more and less than 1.0° and an average sintered grain size of 10 μm or more.