Share Email Print
cover

Proceedings Paper

Studies of polycrystalline pentacene thin-film transistors at the microscopic level
Author(s): Horng-Long Cheng; Wei-Yang Chou; Chia-Wei Kuo; Yu-Shen Mai; Fu-Ching Tang; Szu-Hao Lai
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

The electronic transport properties of polycrystalline pentacene-based thin film transistors (TFTs) were investigated at the microscopic level using microRaman spectroscopy. All the pentacene film, which were thermally evaporated as a layer with thickness of 70 nm, featured polycrystalline structure with only "thin film" phase polymorph and grain morphology as verified by x-ray diffraction (XRD) measurements. We have investigated the molecular vibrational modes of pentacene in the active channel during operations the organic TFT devices using in-situ Raman spectroscopy. Extra vibrational modes resulting from vibrational coupling effect in pentacene film were studied. The interlayer and intralayer intermolecular vibrational coupling energy was calculated from the Davydov splitting using a simple coupled-oscillator model. The results suggest that the C-H in-plane bending vibrational coupling energy of pentacene molecules in solid film is affected by operating device. Additionally, the aromatic C-C stretching vibrational modes also were investigated. However, it is rather difficult to obtain the variations of lattice parameters of pentacene film in a very small active channel by using electron diffraction and XRD. At the same time, MicroRaman technique provides the capability to explore the intermolecular coupling and molecular structure modifications.

Paper Details

Date Published: 25 August 2006
PDF: 11 pages
Proc. SPIE 6336, Organic Field-Effect Transistors V, 63361B (25 August 2006); doi: 10.1117/12.678724
Show Author Affiliations
Horng-Long Cheng, National Cheng Kung Univ. (Taiwan)
Wei-Yang Chou, National Cheng Kung Univ. (Taiwan)
Chia-Wei Kuo, National Cheng Kung Univ. (Taiwan)
Yu-Shen Mai, National Cheng Kung Univ. (Taiwan)
Fu-Ching Tang, National Cheng Kung Univ. (Taiwan)
Szu-Hao Lai, National Cheng Kung Univ. (Taiwan)


Published in SPIE Proceedings Vol. 6336:
Organic Field-Effect Transistors V
Zhenan Bao; David J. Gundlach, Editor(s)

© SPIE. Terms of Use
Back to Top