Effect of Charge Carrier Mobility in Channel vs. Source-Drain Region on Vertical Organic Field Effect Transistor Performance

Lateral organic field effect transistors (OFETs), due to lithographic limitations, have channel lengths ranging in micro-meters. Vertical organic field effect transistors (VOFETs) have a channel perpendicular to the gate dielectric which means source and drain electrodes are vertically stacked. The vertical stacking of source and drain electrodes and due to the proximity leads to high off-state current density. There have been multiple efforts to reduce the off-state current and increase the on-state current. The presented simulation work explores the effect of different charge carrier mobility in source-drain region vs. channel region. In general, the charge carrier mobility in organic semiconductors increases with an increase in charge carrier concentration. The simulation results show that by enhancing the charge carrier mobility of the channel region by 10³ orders, the best device performance can be achieved.