INOR 71

We recently discovered that the diode property could be accomplished to CNT devices through the mass transport of lithium ions. As a chemical bed for lithium ions, 1-pyrenemethylamine molecules were functionalized on single channel CNT transistors fabricated by photolithography. Lithium ions were then intercalated between CNT and 1-prenemethylamine on the CNT. In the lithium intercalated CNT transistors, diode-like I-V characteristics were observed over the bias voltage range of -10 to +10 V. We also found that this transistor does not show hysteresis on I-V curve. This diode-like property is due to asymmetric metal-CNT contacts facilitated by lithium ions transported to drain (-) electrode, resulting in the modulation of work function of metal electrodes, hence asymmetric metal-CNT contacts. In order to confirm the mass transport of lithium ions, the population distribution of lithium was examined from diode-like devices by using scanning photoelectron microscopy and space-resolved x-ray photoelectron spectroscopy. This approach using the concept of mass transport of lithium ions to modulate the metal contact characteristics is a simple and promising process that can be further applied to various nanomaterial-based electronic devices.