Electric force microscopy imaging of charge accumulation and barrier lowering at Al/pentacene junction

摘要

We investigated the current-voltage and interface properties of the Al/pentacene/Au sandwiched sample. When the bias voltage was applied between Al and Au, a rectifying current-voltage curve was obtained as expected from the energy diagram. When measured in air, however, the forward current increased slowly to saturation even though the bias voltage was fixed. Cross-sectional electrostatic force microscopy of the interface suggested that a barrier lowering due to hole accumulation at the Al/pentacene junction was responsible.