ETA-Photovoltaics materials Interface optimization
EMSL Project ID
34725
Abstract
We will provide a fundamental scientific foundation to understand the charge transport innovel oxide-based solar cells, and to tailor the transport by doping and/or interface modification of the
material systems. These results will provide the basis for improvements in solar cell efficiency, which is
a primary goal in the quest to harness solar power to meet the world's energy demands. The
research project focuses on proposed extremely thin absorber (ETA) solar cell designs, and consists of
a study of the band alignments between n-type ZnO and common inorganic photon absorber, p-type
semiconductor, and electrode materials in both thin film form and nanostructured devices.
Deposition of well-defined n-type oxides such as ZnO by pulsed laser deposition (PLD) is a signature
strength of our laboratory, and this knowledge will be extended to deposition of inorganic photon
absorber (CdTe) and p-type semiconductor (CuSCN) materials. Band offset measurements by high
resolution x-ray photoelectron spectroscopy (XPS) are another area of expertise, and will provide
valuable information on the efficacy of charge injection from the absorber to the semiconductor oxide,
and from the semiconductor oxide to the electrode. Further, bulk electronic charge transport can be
measured utilizing a multi-functional Physical Property Measurement System (PPMS). With these
results, the band alignments and thus charge transport can be optimized through either cation or anion doping of the n-type ZnO, and/or interface modification. Once optimized materials parameters are determined, they will be applied to nanostructured ZnO deposited by pulsed laser deposition in material stacks similar to solar cell devices.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2009-10-01
End Date
2011-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Jaffe JE, TC Kaspar, T Droubay, and T Varga. 2013. "Band offsets for mismatched interfaces: The special case of ZnO on CdTe (001)." Journal of Vacuum Science and Technology A--Vacuum, Surfaces and Films 31(6):061102. doi:10.1116/1.4816951
Jaffe JE, TC Kaspar, T Droubay, T Varga, ME Bowden, and GJ Exarhos. 2010. "Electronic and defect structure of CuSCN." Journal of Physical Chemistry C 114(19):9111-9117. doi:10.1021/jp101586q