Organic field-effect transistors for nonvolatile memory devices using charge-acceptor layers

We introduce a charge-accepting layer on a gate dielectric to investigate the reversible threshold voltage (Vth) shifts in both p-channel and n-channel organic field-effect transistors (OFETs) using organic semiconductors of pentacene and poly-naphthalene dicarboximide [P(NDI2OD-T2)], respectively. Bottom gate with top drain-source contact structure of both devices exhibited a unipolar property of field-effect transistor behavior. Furthermore, the existence of fullerene (PCBM) and poly(3-hexylthiophene) (P3HT) films as a charge-accepting-like storage layers in p-channel and n-channel devices, respectively, resulted in a reversible Vth shifts upon the application of external gate bias (Vbias). Hence, p-channel OFETs exhibited a memory window of 2.4 V and n-channel OFETs exhibited a memory window of 10.7 V for program and erase electrically upon application of gate bias.