Probing inter-molecular interactions of dinaphthothienothiophene (DNTT) molecules in a transistor device using low-frequency Raman spectroscopy

The packing of Dinaphthothienothiophene (DNTT) molecules, such as their proximities and alignments, can significantly affect the carrier mobility within a device. Since the low-frequency vibrational modes in Raman scattering originate from the intermolecular interactions, they provide direct information about the molecular packing, particularly about their proximities from each other. Therefore, low-frequency Raman scattering turns out to be an indispensable tool to investigate DNTT-based devices for their potential improvements. Here, we report low-frequency Raman investigation on the DNTT molecules in a real transistor device to investigate the intermolecular interactions at a spatial resolution of a few hundreds of nanometers.