Abstract
Implementation of an optically active material on silicon has been a persistent technological challenge. For tandem photovoltaics using a Si bottom cell, as well as for other optoelectronic applications, there has been a longstanding need for optically active, wide band gap materials that can be integrated with Si. ZnSiP2 is a stable, wide band gap (2.1 eV) material that is lattice matched with silicon and comprised of inexpensive elements. As we show in this paper, it is also a defect-tolerant material. Here, we report the first ZnSiP2 photovoltaic device. We show that ZnSiP2 has excellent photoresponse and high open circuit voltage of 1.3 V, as measured in a photoelectrochemical configuration. The high voltage and low band gap-voltage offset are on par with much more mature wide band gap III-V materials. Photoluminescence data combined with theoretical defect calculations illuminate the defect physics underlying this high voltage, showing that the intrinsic defects in ZnSiP2 are shallow and the minority carrier lifetime is 7 ns. These favorable results encourage the development of ZnSiP2 and related materials as photovoltaic absorber materials.
Original language | American English |
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Pages (from-to) | 1031-1041 |
Number of pages | 11 |
Journal | Energy and Environmental Science |
Volume | 9 |
Issue number | 3 |
DOIs | |
State | Published - Mar 2016 |
Bibliographical note
Publisher Copyright:© The Royal Society of Chemistry 2016.
NREL Publication Number
- NREL/JA-5J00-66212
Keywords
- tandem photovoltaics
- wide band gap materials
- ZnSiP2