Abstract
Solar cells made from multicrystalline silicon material, which still represent the majority of solar cells produced today, are by nature inhomogeneous devices. Their bulk excess carrier lifetime, which decisively influences the short circuit current density, the saturation current density, and the effective bulk diffusion length, may vary from position to position by an order of magnitude or more. Moreover, such cells may contain ohmic shunts and, in particular in the edge regions, positions of significant depletion region recombination current. The classical local characterization method for solar cells is light beam‐induced current (LBIC) mapping. This method does not give direct information on factors influencing the dark current density. A reliable quantitative local characterization of inhomogeneous cells can be performed by combining dark lock‐in thermography (DLIT) with electro‐ and photoluminescence (EL and PL) imaging. In this contribution, the well‐established and the most recent findings on the application of these methods are reviewed and typical application examples are presented. It is shown that luminescence imaging is most appropriate for local series resistance imaging and for qualitatively imaging of all kinds of recombination‐active defects. DLIT, on the other hand, shows a lower spatial resolution, but is most appropriate for imaging local two‐diode parameters like depletion region‐ and bulk saturation current densities, the latter allowing to draw conclusions also to the local short circuit current density. A comprehensive local characterization of silicon solar cells is possible by applying both DLIT and luminescence imaging, which complement each other.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.