GaAsSb Core-Shell Nanowires for 1.4-1.7 μm Emission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge lies in developing semiconductor nanowires with a GaAsSb core and a GaAsSbN shell that exhibit an emission wavelength maximum of greater than 1.35 μm, which has not been previously reported, and requires advanced methods for growth and control.
Innovation Solution
The development of GaAs(1−y)Sby/GaAs(1−x)SbxN core-shell nanowires, where y=0.03-0.07 and x=0.27-0.34, using molecular beam epitaxy and vapor phase growth mechanisms, allowing for precise control of composition and structure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional nanowire growth methods are used, then growth is achieved, but emission wavelength cannot exceed 1.35 μm
Solution Approach 1:
The patent applies parameter changes by systematically varying composition parameters (Sb content x=0.08-0.15, N content y=0.005-0.035) and growth parameters (temperature 500-600°C, V/III ratio 5-20) to achieve emission wavelengths exceeding 1.35 μm. This resolves the contradiction by finding optimal parameter combinations that enable longer wavelength emission while maintaining controllable growth conditions.
Solution Approach 2:
The patent uses composite materials by creating core-shell nanowire structures with GaAs/GaAsSb cores and GaAsSbN shells. This composite approach enables bandgap engineering to achieve emission wavelengths >1.35 μm while the shell structure provides growth stability, resolving the contradiction between extended wavelength and manufacturing control.
2Temperature
If Sb concentration is increased to extend emission wavelength, then emission wavelength increases, but growth stability deteriorates
Solution Approach 1:
The patent applies local quality by creating a core-shell structure where the core region (GaAs/GaAsSb) has high Sb concentration for wavelength extension, while the shell region (GaAsSbN) has moderate Sb concentration for growth stability. This spatial differentiation resolves the contradiction by allowing high Sb content locally in the core without compromising overall growth stability.
Solution Approach 2:
The patent uses preliminary action by forming a stable core structure first, then depositing the shell layer that accommodates higher Sb content. This sequential approach allows the system to establish growth stability before introducing higher Sb concentrations, preventing growth deterioration while achieving extended emission wavelengths.
3Manufacturing precision
If core-shell structure is implemented for bandgap tuning, then emission wavelength control improves, but device complexity increases
Solution Approach 1:
The patent applies segmentation by dividing the nanowire into core and shell segments with distinct compositional functions. The core (GaAs/GaAsSb) provides structural foundation while the shell (GaAsSbN with x=0.08-0.15) enables precise bandgap tuning. This segmentation achieves superior wavelength control while maintaining manageable structural complexity through clear functional division.
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
These nanowires achieve an average emission maximum of 1.4-1.7 μm at room temperature, demonstrating enhanced optical properties and potential for applications in infrared photodetection and quantum networking.
Implementation Method 1
methodologies of nanowire formation and thin film formation are not readily interchangeable... such as molecular beam epitaxy (MBE)
Implementation Method 2
various vapor phase growth mechanisms
Data Source
AI summary
Compositions comprising Group V/III nanowires, and methods of making such nanowires are described. Some compositions comprise one or more core-shell nanowires comprising a core and a first shell surrounding or substantially surrounding the core. The core is formed from GaAs(1−y)Sby, where y=about 0.03-0.07 and the first shell is formed from GaAs(1−x)SbxN, where x=0.27-0.34. The nanowires have an average emission maximum of 1.4-1.7 μm. Some nanowires further comprise a second shell surrounding or substantially surrounding the first shell. The second shell is formed from a Group V/III material such as Ga1−mAlmAs, where m=0-0.2. Some nanowires have the structure GaAs(0.93-0.97)Sb(0.03-0.07)/GaAS(0.66-0.73)Sb(0.27-0.34)N/Ga(0.8-1)Al(0-0.2)As.