Organic semiconductors based on vacuum-deposited films of fused-ring polycyclic aromatic hydrocarbon have great potential to be utilized as an active layer for electronic and optoelectronic devices. In this study, pentacene thin films and electrode materials were deposited by Organic Molecular Beam Deposition (OMBD) and vacuum evaporation respectively. For the gate dielectric layer, photoacryl (OPTMER PC403 from JSR Co.) was spin-coated and cured at 220℃. Electrical characteristics of the device were investigated, where the channel length and width was 50 μm and 5 mm. It was found that field effect mobility was 0.039 cm2V-1s-1, threshold voltage was -8 V, and on/off current ratio was 106. Further details will be discussed.