M. Fernanda Villa-Bracamonte, J.R. Montes-Bojorquez, A. Ayon
University of Texas at San Antonio,
Keywords: photovoltaics, perovskite, MAPbI3, ellipsometry
Summary:Perovskite Solar Cells (PSCs) have become a promising photovoltaic technology due to their excellent properties such as tunable band gap, large absorption coefficient and electronic properties of the active material. However, the rapid development of PSCs has led to the necessity of viable metrology technologies to meet the requirements towards a large-scale production. In this regard, spectroscopic ellipsometry is considered the most appropriate technique due to its outstanding measurement features such as accuracy, reproducibility, and nondestructive testing. In this work, we present a comprehensive multilayer modeling approach to investigate the optical properties of a PSC by the ellipsometry analysis of a Methylammonium Lead Iodide (MAPbI3) perovskite/PEDOT:PSS/ITO film stack on a glass substrate. The absorption coefficient obtained from the model is compared to the ultraviolet-visible (UV-Vis) spectroscopy measured absorption spectra, while the thickness of each layer is validated by profilometry. We propose that spectroscopic ellipsometry characterization can be used at the different stages of the PSCs fabrication process in order to understand the different mechanisms that impact the final performance of the photovoltaic device.