RT Journal Article T1 Long-Term Field Screening by Mobile Ions in Thick Metal Halide Perovskites: Understanding Saturation Currents A1 Almora Rodríguez, Osbel A1 Miravet Martínez, Daniel A1 Gelmetti, Ilario A1 Garcia Belmonte, Germà K1 Charge carrier mobility K1 Debye length K1 Drift-diffusion simulations K1 Ionic conductivity in solid state matter K1 Metal halide perovskites K1 Semiconductor interfaces K1 X-ray detectors AB Metal halide perovskite-based semiconductor devices with micrometer-to-millimeter-thick perovskite layers show a current response upon polarization which evolves up to several hours, transiting several regimes. This is the case of X-ray detectors where the use of absorber perovskites produces instabilities in the dark reverse saturation current hindering the signal processing. Even though these phenomena are often attributed to the electronic-ionic conductivity and the interface phenomena in these perovskites, a proper theoretical description is missing. Herein, the numerical simulation study reproduces the main experimental trends and explains the origin of some of the apparently-always-increasing current transients in thick perovskite samples. The mobile ion concentration and mobility are correlated with three main transport regimes and interpretation and parameterization are provided to the current saturation time in terms of the ionic screening of the electric field toward the interfaces. The final steady-state under reverse polarization is found as diffusion-limited electronic current, which results from abrupt mobile ion depletion proportional to the Debye length in the vicinity of a contact. The conclusions suggest the material optimization of the contact interfaces as a pathway to reduce the long current saturation times in these devices. PB John Wiley & Sons YR 2022 FD 2022-09-06 LK http://hdl.handle.net/10433/15308 UL http://hdl.handle.net/10433/15308 LA en NO Physica Status Solidi RRL, 2022, 16, 2200336 NO Universidad Pablo Olavide. Departamento de Sistemas Físicos, Químicos y Naturales DS RIO RD May 24, 2026