Title :
a-Si/c-Si1−xGex/c-Si heterojunction solar cells
Author :
Hadi, Sabina Abdul ; Nayfeh, Ammar ; Hashemi, Pouya ; Hoyt, Judy
Author_Institution :
Masdar Inst. of Sci. & Technol., Abu Dhabi, United Arab Emirates
Abstract :
The performance and material quality requirements of thin film a-Si/c-Si1-xGex/Si heterojunction solar cells are investigated by modeling and simulation. The effects of Ge content, Si1-xGex thickness, Si1-xGex lifetime and a-Si/c-Si1-xGex interfacial quality have been studied. The simulations predict that Si1-xGex based thin film solar cells provide a significant increase in solar cell output current for Ge fractions larger than 30%, due to the narrower band-gap and increased absorption. In addition, the efficiency of thin (2μm) Si1-xGex solar cells surpasses that of Si for minority carrier lifetimes larger than 0.5μs. For these 2μm thin layers, simulations predict reduced material quality requirements for Si1-xGex cells, with a clear performance advantage relative to Si based solar cells.
Keywords :
carrier lifetime; germanium compounds; silicon compounds; solar cells; thin film devices; Si1-xGex; heterojunction solar cells; material quality requirements; minority carrier lifetimes; size 2 mum; thin film solar cells; Charge carrier lifetime; Epitaxial growth; Heterojunctions; Photonic band gap; Photovoltaic cells; Silicon; Efficiency; Heterojunction; Lifetime; SiGe; Solar; thin film;
Conference_Titel :
Simulation of Semiconductor Processes and Devices (SISPAD), 2011 International Conference on
Conference_Location :
Osaka
Print_ISBN :
978-1-61284-419-0
DOI :
10.1109/SISPAD.2011.6035083
