Forward tunneling current in {111}-oriented homoepitaxial diamond p–n junction

We investigated the current transport mechanism of {111}-oriented homoepitaxial diamond p–n junction. It is found that the slope of the current–voltage characteristic in semi-logarithmic scale is constant in a wide range of temperatures and the pre-exponential factor is weakly temperature dependent. Our analysis show that the dominant transport mechanism in forward bias is tunneling through deep levels with characteristic energies of 260 meV and 102 meV. The reduced masses, obtained by the tunneling energies, suggest that the carriers involved in the tunneling current are electrons.

► The mechanism responsible for current transport in diamond p–n junction has been studied.
► We performed current voltage and capacitance–voltage experiments in a wide range of temperatures.
► The dominant transport mechanism in forward bias was found to be a tunneling process.
► According to our analysis, the carriers responsible of the tunneling mechanism are electrons.