Current-Voltage Properties of Schottky Contact Formed by Copper Layer Deposited on Ion-Implanted P-Type Diamonds

We have formed a Schottky contact on p-type diamond substrates doped only by boron ion implantation process. The doping concertation in the drift layer was 4×10^18 cm^-3 and that beneath the Ohmic contact layer was about 1×10^21 cm^-3 in order to reduce the contact resistance at the Ohmic contact. We investigate the rectifying properties for the Schottky electrode fabricated by copper layer. The observed current between two Ohmic electrodes linearly depended on the applied voltage. From the I-V characteristics between the Ohmic and Schottky contacts, the rectification behavior was not clearly observed for the case of copper electrode, and rectification ratio, which is the current ratio of forward direction to reverse direction, was considerably low.