Electrical properties of in-situ grown and transferred organic nanofibers

摘要

Para-hexaphenylene (p6P) molecules have the ability to self-assemble into organic nanofibers, which exhibit a range of interesting optical and optoelectronic properties such as intense, polarized luminescence, waveguiding and lasing. The nanofibers are typically grown on specific single-crystalline templates, such as muscovite mica, on which mutually parallel nanofibers are self-assembled upon vapor deposition of the organic material under high vacuum conditions. Besides such single-crystalline templates, the nanofibers can also be grown on non-crystalline gold surfaces, on which the orientation of the nanofibers can be manipulated by structuring the gold surface prior to para-hexaphenylene (p6P) deposition. In this work it is demonstrated, how such organic nanofiber growth can be controlled by modifying the design of the underlying gold structures prior to growth. Here, the investigated designs include pinning lines and gratings. We demonstrate how gold gratings fabricated on an insulating substrate can enable electrical contact to in-situ grown p6P nanofibers. Furthermore, the electrical characteristics of in-situ grown fibers are compared to that of transferred p6P nanofibers. The transferred nanofibers are initially grown on muscovite mica, and subsequently transferred onto a target substrate by drop casting, and electrodes are applied on top by a special shadow mask technique.