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GaAs core--shell nanowires for photovoltaic applications
Josef A Czaban1, David A Thompson, Ray R LaPierre
1Centre for Emerging Device Technologies, McMaster University, Hamilton, Ontario, Canada L8S 4L7.
Nano Letters
|January 16, 2009
Summary
Tellurium (Te) doping in gallium arsenide (GaAs) core-shell nanowires impacts photovoltaic device morphology and efficiency. Increased Te doping duration led to reduced solar cell performance.
Area of Science:
- Materials Science
- Nanotechnology
- Semiconductor Physics
Background:
- Gallium arsenide (GaAs) core-shell nanowires are promising for photovoltaic applications.
- Controlling dopant effects on nanowire morphology is crucial for device performance.
Purpose of the Study:
- To investigate the role of tellurium (Te) as an n-type dopant in GaAs core-shell nanowires.
- To understand the impact of Te doping on nanowire morphology and photovoltaic device characteristics.
Main Methods:
- Vapor-liquid-solid (VLS) growth process using molecular beam epitaxy (MBE).
- Fabrication and characterization of Te-doped GaAs core-shell p-n junction nanowires.
- Evaluation of photovoltaic device operating characteristics.
Main Results:
- Tellurium (Te) doping significantly altered the morphology of GaAs nanowires.
- Te exhibited a surfactant effect, promoting radial nanowire growth.
- Increased Te-doped GaAs growth duration negatively impacted solar cell efficiency.
Conclusions:
- Te doping influences GaAs nanowire growth and photovoltaic performance.
- Optimizing Te doping concentration and growth duration is essential for efficient GaAs nanowire solar cells.
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