Abstract
Mixed organic–inorganic halide perovskites are finding strong interest as thin film solar cell materials. XPS depth profiling of a spin‐coated (FAPbI 3 ) 0.95 (MAPbBr 3 ) 0.05 perovskite thin‐film solar cell, has been performed. Profiles have been recorded using traditional monatomic and cluster ion beam bombardment and compared to those obtained using a new femtosecond laser ablation (fs‐LA) approach. The femtosecond laser employed has a wavelength of 1030 nm and a pulse length of 160 fs. Monatomic and cluster ion sputter depth profiling of the halide perovskite results in preferential sputtering of C, N and I and the appearance of Pb 0 in the Pb 4f spectrum as a preferential sputtering artefact. fs‐LA depth profiling is shown to retain the original composition and chemical state information of the perovskite layer with no chemical damage. An ablation rate of ≈33 nm through the perovskite layer was found at an incident laser energy of 42 μJ per pulse. A combined fs‐LA/monatomic sputtering depth profile enabled all layers in the cell to be identified whilst retaining the true composition of the perovskite layer.