SPLTRAK Abstract Submission
Spectroscopic Ellipsometry Analysis and Quantum Efficiency Simulation of CuInSe2 Solar Cells
Dhurba R. Sapkota1, Ambalanath Shan1, Balaji Ramanujam1, Puja Pradhan1, Richard Irving1, Adam B. Phillips1, Michael J. Heben1, Randy J. Ellingson1, Sylvain Marsillac2, Nikolas J. Podraza1, Robert W. Collins1
1University of Toledo, Toledo, OH, United States
/2Old Dominion University, Norfolk, VA, United States

CuInSe2 (CIS) thin-film solar cells in the substrate configuration were fabricated and studied using spectroscopic ellipsometry (SE). Starting with the parameterized complex dielectric functions of the individual component layers, SE analysis was performed using a step-wise procedure that ranks the fitting parameters according to their ability to reduce the mean square error of the fit. The resulting layer thicknesses and dielectric functions were used to simulate the external quantum efficiency (EQE) of the device assuming complete active layer collection. Electronic losses were identified by comparison with the measured EQE. Simulation results show that complete collection yields a short circuit current density of 42.62 mA/cm2. The goal of this study is to develop and optimize 1.0 eV bandgap CIS for use as a bottom cell absorber of multijunction solar cells.