Novel Method for Measuring Carrier Diffusion Lengths in Metal-Halide Perovskites

Herein, it is demonstrated that the carrier diffusion lengths in metal-halide perovskite films can be estimated from contactless quasi-steady-state photoconductance measurements applying an approximate analysis. The approach to metal-halide perovskite layers of different compositions is applied, which is fabricated by wet-chemical processing and coevaporation. The extracted diffusion lengths are in the order of several micrometers for both examined perovskite layers and hence sufficiently large, i.e., much larger than the film thickness, to process high-efficiency solar cells from them. The presented analysis provides a useful and easy-to-apply methodology for the fast assessment of the electronic quality of metal-halide perovskite layers in the lab, without the need of complete solar cell processing.