Deposition of Al-doped ZnO thin-films with radio frequency magnetron sputtering for a source/drain electrode for pentacene thin-film transistor

Abstract

Al-doped ZnO thin-films were deposited with the radio frequency magnetron sputtering technique at various temperatures and sputtering powers for a source/drain electrode in the pentacene thin-film transistor. With the increase in the deposition temperature and the decrease in the radio frequency sputtering power, the crystallinity was increased and the surface roughness was decreased, which lead to the decrease in the electrical resistivity of the film. Al-doped ZnO film deposited at 200 degrees C and sputtering power of 50 W showed a low resistivity (9.73 x 10(4) mu Omega cm), high crystallinity, low roughness and uniform surface morphology. The pentacene thin-film transistor fabricated with Al-doped ZnO film as a source/drain electrode showed a device performance, (mobility: 7.89x 10(-3) cm(2)/Vs and on/off ratio: similar to 5x10(4)) which is comparable with an indium tin oxide electrode grown at room temperature. (C) 2009 Elsevier B.V. All rights reserved.