Field-dependent mobility of highly oriented pentacene thin-film transistors

Pentacene thin films were grown by vacuum evaporation method. The structural properties of the films were characterized by X-ray diffraction and atomic force microscopy. Carrier transport characteristics of pentacene thin film transistors were investigated in terms of the field-dependent mobility. It was found in X-ray diffraction analysis that moderate thermal treatment significantly improved the film quality, but little modification was observed under the atomic force microscope and the electrical characteristics measurement. Thus, it can be concluded that it is of great importance to control the surface conditions and the early stage of film growth.