title: Amorphous-to-crystalline phase transformation of thin film rubrene.
abstract: We report on the amorphous-to-crystalline phase transformation of rubrene thin films. The crystallization of the organic thin films displays disk-like domains whose nucleation and growth follow phase transformation kinetics well-established for inorganic materials under certain time and temperature conditions. We understood that the crystallization of amorphous rubrene thin film shows site-saturated nucleation behavior while the crystalline growth involves both diffusion and interface-controlled kinetics displaying spherulitic disk growth behavior. The activation energy of the transformation kinetics was about 0.78 eV on hexamethyldisilazane-functionalized SiO(2) substrate as mostly consumed at the growth process. The crystallization kinetics changes with the film substrate; more hydrophobic substrate induces a lesser number of crystalline nuclei while causing faster growth of those nuclei.
authors.affiliation: Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749, Korea.
authors.forename: Se-Woong
authors.initials: SW
authors.lastname: Park
authors.forename: Jeong-Min
authors.initials: JM
authors.lastname: Choi
authors.forename: Kwang Hyun
authors.initials: KH
authors.lastname: Lee
authors.forename: Han Woong
authors.initials: HW
authors.lastname: Yeom
authors.forename: Seongil
authors.initials: S
authors.lastname: Im
authors.forename: Young Kook
authors.initials: YK
authors.lastname: Lee