Phenyl Derivative of Dibenzothiopheno[6,5-b:6′,5′-f]-Thieno[3,2-b]Thiophene (DPh-DBTTT): High Thermally Durable Organic Semiconductor for High-Performance Organic Field-Effect Transistors

Phenyl-substituted heteroacene, diphenyl-dibenzothiopheno[6,5-b:6',5'-f]-thieno[3,2-b]thiophene (DPh-DBTTT), is introduced as a thermally durable high-performance organic semiconductor. The DPh-DBTTT single crystals exhibit hole mobility up to 31.9 cm(2) V-1 s(-1), and the vacuum-deposited DPh-DBTTT thin-film transistors show a maximum mobility of 6.32 cm(2) V-1 s(-1). X-ray crystallographic analysis reveals that the small tilting angle between the phenyl substituent and the DBTTT core reduces the reorganization energy dramatically. The structure-property relationships are thoroughly investigated using atomic force microscopy, transmission electron microscopy, and grazing incidence X-ray diffraction analyses, in addition to charge-transport studies. The vacuum-deposited DPh-DBTTT thin-film transistors show superior thermal durability compared to the core DBTTT, which is highly valuable for device processability.