Abstract
We have fabricated organic field effect transistors constructed with pentacene active layers grown by vacuum deposition, polycarbonate (PC) gate dielectric layers fabricated by spin-coating and polyethylene naphthalate thin films used as substrates. The surface morphology of PC thin films was observed by atomic force microscopy (AFM). It was confirmed that the surface morphology of PC thin films had smoothness at a molecular level, although there was a problem to keep a balance between insulation property and smoothness of the surface. From the performance of the obtained organic field effect transistor, the carrier mobility was estimated to be 0.7×10-3 cm2/Vs, the on/off ratio to be 102 and the sub threshold voltage to be 32 V.
