Effects of Polymeric Dielectric Morphology on Pentacene Morphology and Organic TFT Characteristics

Abstract

Abstract.In this paper, we report on the effects of the polymeric dielectric morphology on pentacene morphology and organic thin film transistor (TFT) characteristics. The morphology and thickness of cyclo-olefin polymer (COP) dielectric could be controlled by selecting a solvent. Higher the solvent's boiling point is, thinner and smother COP films could be obtained. Using the solvent of trimethylcyclohexane, the spin-coated COP films of ca. 330 nm with the peak-to-valley of 7.35 nm and the roughness of root mean square of 0.58 nm were obtained, and pentacene TFT showed high mobility of 2.0 cm 2 V -1 s -1 , which originated from highly ordering of pentacene thin films deposited on the smoother and thinner COP films.