Non-equilibrium crystallization and spatial fingerprints in flash IR-annealed halide perovskite films

) is comparable between the two compositions, indicating that the additive redistributes intragrain disorder spatially rather than changing its total amount. These results are consistent with additive-mediated narrowing of the accessible crystallization pathway under rapid annealing. More broadly, the workflow shows that bright-field imaging can serve as a scalable probe of non-equilibrium crystallization in solution-processed semiconductors and provides a transferable route for linking processing, crystallization dynamics, and final microstructure in rapidly solidified thin films.