On the Extraction of Charge Carrier Mobility in High-Mobility Organic Transistors

Transistor parameter extraction by the conventional transconductance method can lead to a mobility overestimate. Organic transistors undergoing major contact resistance experience a significant drop in mobility upon mild annealing. Before annealing, strong field-dependent contact resistance yields nonlinear transfer curves with locally high transconductances, resulting in a mobility overestimate. After annealing, a contact resistance below 200 Omega cm is achieved, which is stable over a wide V-G range.