Gamma-ray Irradiated Organic Thin Film Transistors Based on Perfluoropentacene with Polyimide Gate Insulator

抄録

N-channel field effect transistors with a Si/polyimide(PI)/perfluoropentacene/Au structure were fabricated, and irradiated wby gamma-ray ith a Co⁶⁰ source. The changes of the drain current ID vs. source/drain voltage V_SD (I_D - V_SD) characteristics were measured after every 200 Gray in silicon (Gy_Si) irradiations up to the total dose of 1200 Gy_Si. The drain current ID gradually increased up to the total dose of 1200 Gy_Si. The threshold voltage V_th decreased up to 400 Gy_Si, and gradually recovered above 600 Gy_Si. The mobility μ was almost unchanged up to 1200 Gy_Si. Those behaviors were explained by accumulation of positive trapped charge within the gate insulator PI near the interface. Evidence for the accumulation of interface traps was hardly observed.