Elucidation of ambient gas effects in organic nano-floating-gate nonvolatile memory

Pentacene-based organic field-effect transistor nonvolatile memories employing nano-floating-gate show high performance in vacuum, typically with field-effect mobility of 0.6 cm2/Vs, memory window of 45 V, reading ON/OFF ratio over 106, and excellent retention ability and programming/erasing endurance. The memory performance is unstable in air, which is demonstrated to result mainly from the device operation instability in O2. The O2-induced acceptor-like trap states reduce the electron supply in pentacene during programming, limiting the electron trapping into the nano-floating-gate and thus suppressing the positive threshold voltage shift. The corresponding hole trapping during erasing is not effectively influenced by the ambient gas effects.