Template Effects of Tetrakis(thiadiazole)Porphyrazine to the Structures of Phthalocyanine Thin Films

Molecular templating is an attractive method to improve the crystallinity of organic thin films and control the molecular orientations in them. Here, we report on the templating effects of an organic n-type semiconductor, tetrakis(thiadiazole)porphyrazine (H 2 TTDPz), on the structure and optical absorption of a p-type semiconductor, copper phthalocyanine (CuPc). X-ray diffraction measurements for the double layer thin films, CuPc/H 2 TTDPz, indicate a flat-on structure of CuPc, which is copied by the structure of the H 2 TTDPz thin films, in spite of that the CuPc thin films usually form edge-on type thin films. The optical absorption measurements show new low-energy transitions in the templated CuPc films.