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Structural variations of Si1-xCx and their light absorption controllability
Jihyun Moon1, Seung Jae Baik, Byungsung O
1KIER-UNIST Advanced Center for Energy, Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon, 305-343, South Korea. sjbaik@hknu.ac.kr.
Nanoscale Research Letters
|September 8, 2012
Summary
Third-generation photovoltaics utilize tunable bandgap materials like silicon-carbon (Si1-xCx) alloys with embedded nanocrystalline silicon. Stoichiometry and oxygen content critically control light absorption in these advanced solar cell materials.
Area of Science:
- Materials Science
- Nanotechnology
- Photovoltaics
Background:
- Third-generation photovoltaics require tunable bandgap materials for enhanced efficiency.
- Nanocrystalline silicon (nc-Si) embedded in silicon-carbon (Si1-xCx) alloys present a promising avenue.
- Controlling light absorption is crucial for optimizing nc-Si embedded Si1-xCx absorber materials.
Purpose of the Study:
- To investigate the light absorption controllability of nc-Si embedded Si1-xCx.
- To compare the properties of nc-Si embedded Si1-xCx with stoichiometric SiC.
- To propose a design strategy for nc-Si embedded absorber materials for next-generation photovoltaics.
Main Methods:
- Production of nc-Si embedded Si1-xCx via thermal annealing of Si-rich Si1-xCx and superlattice structures.
- Investigation of light absorption properties.
- Comparative analysis with stoichiometric SiC.
Main Results:
- Stoichiometric changes in the matrix material significantly influence light absorption.
- Incorporation of oxygen plays a key role in tuning light absorption.
- Distinct characteristic differences were observed between nc-Si embedded Si1-xCx and stoichiometric SiC.
Conclusions:
- The study highlights the importance of matrix stoichiometry and oxygen content for light absorption control.
- Results provide insights for designing advanced nc-Si embedded absorber materials.
- A design strategy for third-generation photovoltaic materials is discussed based on experimental findings and literature.
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