Angle-Dependent Polarized Raman Spectroscopy of TIPS Pentacene Single-Crystalline Domains Deposited on Au-Striped Substrates

Abstract

ABSTRACT6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) was deposited on SiO2/Si substrates with Au stripes using electrostatic spray deposition (ESD). We observed that crystalline domains on the substrates were preferentially oriented. To elucidate this phenomenon, the correlation between the orientation direction and stripe direction was investigated by angle-dependent polarized Raman spectroscopy. Since the acene planes in TIPS pentacene take an edge-on orientation on the substrates, C-C ring stretch modes can be used to probe the in-plane orientation. We found that the long molecular axis of acene planes is inclined at about 50° or 110° from the stripe direction. This result suggests that the molecular orientation of the crystalline domains can be controlled by the stripes.