Luminescence effects on subcell current–voltage analysis in InGaP/GaAs tandem solar cells

Abstract

We investigate the role of luminescence effects on the analysis of solar cell properties. InGaP/GaAs tandem solar cells fabricated using hydride vapor phase epitaxy have a luminescent coupling (LC) efficiency of 0.6% from the top to the bottom subcell. We investigate the impact of LC on subcell current-voltage curve analysis using electroluminescence (EL) measurements. EL efficiency measurements were performed using a reference InGaP single-junction device. It was found that the luminescence extraction from the top subcell, and therefore its luminescence collection efficiency, is lower than that from the bottom subcell. This is due to LC from the top subcell to the bottom subcell. By considering the luminescence extractions of each subcell, more reasonable subcell voltages than those found by conventional methods can be obtained. © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.