AVS 56th International Symposium & Exhibition
    Thin Film Monday Sessions
       Session TF1+PV-MoA

Paper TF1+PV-MoA10
Novel Solar Cells based on a ZnGeAs2 Absorber Layer

Monday, November 9, 2009, 5:00 pm, Room A8

Session: Chalcogenide Photovoltaics
Presenter: T.J. Peshek, National Renewable Energy Laboratory and Arizona State University
Authors: T.J. Peshek, National Renewable Energy Laboratory and Arizona State University
T.J. Coutts, National Renewable Energy Laboratory
T.A. Gessert, National Renewable Energy Laboratory
Z.Z. Tang, Arizona State University
L. Zhang, Arizona State University
N. Newman, Arizona State University
M. van Schilfgaarde, Arizona State University
Correspondent: Click to Email
We present the latest results on the development of a novel thin film solar cell based upon the direct gap chalcopyrite semiconductor ZnGeAs2. This material has long been viewed as a promising solar material for high efficiency multijunction cells due to it being lattice matched to GaAs and having a band gap of about 1.1 eV. In light of recent advances in single junction solar cells based on chalcopyrite materials such as CuInSe2 we have fabricated the first, to our knowledge, single junction cell based on ZnGeAs2. Initial tests show the devices to have low conversion efficiencies because the photogenerated currents are low. However, we find that the open-circuit voltage in our first tests is approximately 0.135 V. It is our hypothesis based on the J-V curves that the current sourced by the cell can be improved significantly at this point by reducing the series resistance of the device and minimizing any shunts that seem to be present in these devices. The cell is structured according to the superstrate configuration using RF sputtered CdS as the n-type buffer layer. The p-type ZnGeAs2 absorber was deposited at about 600 K by pulsed laser deposition.

This work is supported by DOE-EERE grant DE-FG36-08GO18002, NREL, and Arizona State University. This abstract subject to governmental rights.