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The morphologies of the deposits SnI2 and CdI2, which formed on the surface of a silicon crystal during vapor-solid transition, were studied. The SnI2 fractal structures and the CdI2 self-organizing structures were observed by scanning electron microscopy. It is most significant that the SnI2 fractal structures were composed of nanograins grown at the advancing front of SnI2 crystal accumulation, and showed a transient from equilibrium to non-equilibrium growth. The transient occurred as the cooling rate was increased up to 1000 K/min. The CdI2 self-organizing sunflower-like structures were composed of CdI2 nanocrystals, and indicated an anomalous growth mechanism. The experimental results suggest that the iodide thin films can give rise to fractal structures or self-organizing structures resulting from non-equilibrium growth processes.