The crystal nucleation in the liquid phase deposition process for perovskite thin film fabrication

Abstract

The crystallization process during the preparation of perovskite thin films significantly impacts film morphology, coverage, and overall performance. While the LaMer model qualitatively suggests that higher crystallization rates correlate with increased nucleation density and improved thin film uniformity, quantitative investigations in this domain remain scarce. This study employs classical homogeneous nucleation theory to quantitatively assess perovskite crystallization rates, specifically examining the influence of temperature, evaporation mass transfer coefficient, and solute diffusion rate on crystallization driving force, nucleation rate, and nucleus population. Results demonstrate that elevated temperatures and enhanced evaporation mass transfer coefficients accelerate crystallization rates and increase nucleus density, with the latter exhibiting a more pronounced effect on nucleus proliferation. Conversely, elevated solute diffusion rates suppress both crystallization rate and nucleus density. These findings offer valuable insights for optimizing process parameters during perovskite thin film fabrication.