Contactless Series Resistance Imaging of Perovskite Solar Cells via Inhomogeneous Illumination

TL;DR

This paper introduces a contactless, non-invasive imaging technique using inhomogeneous illumination and photoluminescence to map series resistance in large-area perovskite solar cells, enabling defect detection without electrical contact.

Contribution

The study presents a novel contactless imaging method for series resistance mapping in perovskite solar cells, applicable to fully processed devices and capable of detecting high-resistance features.

Findings

Successfully visualized series resistance variations in perovskite cells.

Validated the method against contacted luminescence imaging techniques.

Demonstrated potential for application in tandem solar cell sub-cells.

Abstract

A contactless effective series resistance imaging method for large area perovskite solar cells that is based on photoluminescence imaging with non-uniform illumination is introduced and demonstrated experimentally. The proposed technique is applicable to partially and fully processed perovskite solar cells if laterally conductive layers are present. The capability of the proposed contactless method to detect features with high effective series resistance is validated by comparison with various contacted mode luminescence imaging techniques. The method can reliably provide information regarding the severeness of the detected series resistance through photo-excitation pattern manipulation. Application of the method to sub-cells in monolithic tandem devices, without the need for electrical contacting the terminals, appears feasible.