GaN Mesa Growth Substrates With Differentiated Porosification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for manufacturing growth substrates for InGaN diodes require spatially localized dopant implantations, making the process complex and inefficient for achieving various porosification levels necessary for emitting or detecting light at different wavelengths.
Innovation Solution
A method involving a crystalline stack with a doped bottom layer and an indium-containing top layer, where the bottom layer is porosifiable at a specific electrical voltage and the top layer is not, allowing for the creation of mesas with varying porosification levels through electrochemical porosification without the need for spatially localized dopant implantations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If spatially localized implantation of dopants is implemented to achieve various porosification levels, then the manufacturing precision of porosification levels is improved, but the device complexity increases
Solution Approach 1:
The patent changes the doping level parameter across different mesas to achieve various porosification levels. By varying the doping concentration in the InGaN layer from mesa to mesa, the electrochemical porosification process produces different porosity levels without requiring complex spatially localized implantation, thus resolving the contradiction between manufacturing precision and device complexity
Solution Approach 2:
The patent applies local quality by creating spatial variation in doping levels across different mesas. Each mesa region has a specific doping level tailored to achieve the desired porosification level, allowing precise control of porosity characteristics in different locations without complex manufacturing steps
2Adaptability or versatility
If spatially localized implantation of dopants is implemented, then the adaptability of porosification levels is improved, but the ease of manufacture deteriorates
Solution Approach 1:
The patent achieves adaptability across various porosification levels by varying the doping level parameter during a single electrochemical porosification process. This approach provides versatile control over porosity while maintaining manufacturing simplicity, as the doping variation can be achieved through standard epitaxial growth techniques rather than complex localized implantation procedures
3Productivity
If various doping levels are created in doped InGaN layers, then the productivity of wavelength-specific diode production is improved, but the device complexity increases
Solution Approach 1:
The patent merges the doping variation step with the epitaxial growth process. By incorporating different doping levels during the initial layer formation rather than requiring separate implantation steps for each mesa, the method achieves efficient production of wavelength-specific diodes while reducing overall process 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
Enables the production of InGaN diodes with different porosification levels, allowing for the emission or detection of light at various wavelengths without the complexity of dopant implantations, thereby simplifying the manufacturing process and enhancing the substrate's functionality.
Implementation Method 1
the doped bottom layer has a doping level predefined so that it is porosifiable at an electrical voltage of predefined value VECE
Implementation Method 2
the top layer has a proportion of indium x2>0 predefined so that it is absorbent of the illumination light radiation
Implementation Method 3
photoassisted porosification of the top portion of the mesa M(2) by emission of the illumination light radiation
Data Source
AI summary
A method for manufacturing a growth substrate, including producing mesas based on GaN having various porosification levels, implementing differentiated steps of electrochemical porosification, non-photoassisted and photoassisted, of various portions of the mesas.