Single crystalline growth of a soluble organic semiconductor in a parallel aligned liquid crystal solvent using rubbing-Treated polyimide films

For directional control of organic single crystals, we propose a crystal growth method using liquid crystal as the solvent. In this study, we examined the formation of 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C₈-BTBT) single crystals using a parallel aligned liquid crystal (LC) cell and rubbing-Treated polyimide films in order to clarify the effects of LC alignment on anisotropic C₈-BTBTcrystal growth. Based on the results, we found that the crystal growth direction of C₈-BTBT single crystals was related to the direction of the aligned LC molecules because of rubbing treatment. Moreover, by optical evaluation, we found that the C₈-BTBT single crystals have a aligned molecular structure.