有機半導体の“隠された”薄膜相

抄録

In thin films of rod–shaped molecules such as pentacene, in addition to the single crystal structure, crystalline phases unique to thin films, the so–called thin–film phases, are formed. These crystalline polymorphs can be easily identified using X–ray diffraction techniques. Nevertheless, the crystalline polymorphs of dinaphthothienothiophene (DNTT), which is classified as a rod–shaped molecule, has not been reported. Previous studies have concluded that the thin film structure of DNTT is identical to that of single crystals. In this study, high–resolution X–ray diffraction measurements are performed for more precise analysis. The results reveal for the first time the existence of the thin–film phase of DNTT. Thus, this study significantly revises the conventional schematic of DNTT thin film growth.