title: Crystallization of rubrene on a nanopillar-templated surface by the melt-recrystallization process and its application in field-effect transistors.
abstract: We present an approach to fabricate a continuous and crystalline rubrene film using the melt-recrystallization process with the assistance of a silicon nanopillar template. Better film morphology, enhanced crystallinity, and mainly oriented crystallites with the c-axis of the orthorhombic rubrene aligning parallel to the nanopillars were obtained as compared to that on a planar substrate. The oriented crystal growth is further modulated by the surface modification. It is suggested that the sidewalls of nanopillars play a key role in mediating the switch of crystal orientation and crystal growth. The obtained nanopillar-templated rubrene film was used to fabricate a vertical field-effect transistor. The device gave a current density of 78 mA cm(-2), on-off ratio around 10(3-4), subthreshold swing of 89.1 mV per decade and transconductance of 154.9 mS cm(-2) on an ODTS-modified substrate surface.
authors.affiliation: Institute of Chemistry, Academia Sinica, Taipei, Taiwan. ytt@gate.sinica.edu.tw.
authors.forename: Chi-Chih
authors.initials: CC
authors.lastname: Ho
authors.forename: Yu-Tai
authors.initials: YT
authors.lastname: Tao