Spatially resolved characterization of solution processed perovskite solar cells using the LBIC technique

Abstract

Perovskite organometal halide based solar cells have recently attracted substantial attention due to high power conversion efficiency and ease of processing. Their photovoltaic performance is significantly affected by perovskite film morphology and uniformity regardless of the deposition method. To compare the performance of perovskite solar cells prepared by different solution-based deposition methods and treatments, we used laser beam induced current (LBIC) to spatially resolve the current collection in different devices. Our results show that devices fabricated by the sequential deposition method yield a higher and more uniform LBIC distribution than those prepared by a single-step deposition. The non-uniformity in the LBIC is attributed to microscopic defects and impurity phases in the perovskite films. LBIC imaging provides useful information that will help optimize the growth conditions for better devices.