Novel soluble pentacene and anthradithiophene derivatives for organic thin-film transistors

Four new solution-processable pentacene- (PEN) and anthradithiophene- (ADT) based organic semiconductors bearing two phenylethynyl (PE-) or triethylsilylphenylethynyl (TESPE-) substituents have been synthesized, characterized, and incorporated in thin-film transistors (TFTs). The molecular structures of these four materials have been determined by single-crystal X-ray diffraction. Thin films of all four compounds have been fabricated via drop-casting and exhibited p-channel OTFT transport with hole mobilities as high as ∼0.01 cm²/V s. Compared to PEN derivatives, ADT-based compounds exhibited superior device performance and photooxidative stability in ambient. The film morphologies and microstructures of these compounds have been characterized by optical microscopy and X-ray diffraction to rationalize device performance trends.