We investigated the growth of quaterrylene thin films on substrates with different surface energy: silicon dioxide (SiO
2) and an octadecyltrichlorosilane self-assembled monolayer (OTS-SAM). We clearly elucidated that a lattice strain induced by the molecular-substrate interaction was essential factor for determining overall growth process and evolving structures. Surface modification by SAMs drastically changed the overall growth process from a Stranski-Krastanov (S-K) mode (layer-plus-island) on the SiO
2 surface to a Frank-van der Merwe (F-M) mode (layer-by-layer) on the OTS surface. Detailed structural analysis by X-ray diffraction techniques revealed that the S-K mode was induced by lattice strain in the initial wetting layers on the SiO
2 surface. On the other hand, strain-free initial layers were already formed at the beginning of growth on the OTS surface, thereby suppressing island formation. Moreover, the films on the SiO
2 surface were found to incorporate high microstrain driven by crystal defects such as dislocations and a mosaic structure. In contrast, few crystal defects were present in the films on OTS surface, demonstrating that OTS treatment efficiently improves the molecular alignment.
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