Optoelectronic design of multijunction wire-array solar cells
Abstract
Microwire solar cells have demonstrated promising optical and photovoltaic performance in arrays of single junction Si wires. Seeking higher efficiencies, we have numerically investigated III-V on Si_(1-x)Ge_x architectures as candidates for tandem microwire photovoltaics via optical and electronic transport modeling. Optical modeling indicates that light trapping is an important design criterion. Absorption is more than doubled by the presence of Al2O3 scattering particles around the wires, leading to high overall light collection despite low wire packing fraction. Texturing of the microwire outer surface, which was found to occur experimentally for GaP/Si microwires, is also shown to enhance absorption by over 50% relative to wires with smooth surfaces, allowing for the use of thinner layers. Finally, full optoelectronic simulations of GaAs on Ge structures revealed that current matching is attainable in these structures and that wire device efficiencies can approach those of planar cells.
Additional Information
© 2011 IEEE. The author would like to thank Michael G. Deceglie and Nick Strandwitz for useful discussion. Support for this work was provided by DARPA (D.B.T-E., A.T.) and the Department of Energy Basic Energy Sciences, Office of Science through the Light Material Interactions Energy Frontier Research Center under contract number DE-SC0001293 (MDK and HAA). D.B.T-E. acknowledges the NSF for fellowship support.Additional details
- Eprint ID
- 93614
- Resolver ID
- CaltechAUTHORS:20190307-092212032
- Defense Advanced Research Projects Agency (DARPA)
- Department of Energy (DOE)
- DE-SC0001293
- NSF Graduate Research Fellowship
- Created
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2019-03-08Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field
- Caltech groups
- Kavli Nanoscience Institute