Observation of nanosize effect in lateral nanoscale p-n and p-i-n junctions

We study nanosize-effect in lateral nanoscale p-n and p-i-n junction devices under light illumination. Current versus voltage (I-V) and current versus time (I-time) characteristics were investigated at low and at room temperature. At low temperature, only p-n junction devices show a photon sensitivity in I-V characteristics due to co-existence of donor-acceptor pair. At room temperature, both devices show photovoltaic nature, i.e., increase of reverse current is observed under light illumination. In addition, devices with narrow channel-width tend to produce larger photocurrent which is ascribed to the nanosize effect.