Suppressive effect of a self-assembled monolayer on the polycrystallization of naphthyl-substituted diamine derivative thin film

We observed the polycrystallization process of a naphthyl-substituted diamine derivative (NPD) thin film on a self-assembled monolayer (SAM)-modified indium–tin–oxide (ITO) substrate. Fluorine-substituted SAM suppressed the growth of the polycrystalline region. After estimating the surface morphology of the polycrystalline region using AFM measurement, correlation between the molecular migration rate on the substrate, the rearrangement rate at the growth point, and the provision rate from the amorphous region clarified the polycrystallization growth mechanism for the NPD thin film. The formation of a channel around the polycrystalline region and the molecular migration rate on the substrate play important roles in polycrystalline region growth.