Barrier height requirements for leakage suppression in diamond power Schottky diodes

Abstract

Diamond Schottky barrier diodes show promise for high voltage, power, and temperature applications due to the outstanding properties of diamond. However, there is still a lack of precise calculation for the Schottky barrier height requirements needed to display their ideal performances. In this work, we exploit semi-empirical models for resistivity and breakdown in p-type diamond, as well as numerical calculations for Schottky contact leakage currents, to outline the challenges and requirements of diamond Schottky diodes. We calculate the required barrier height and temperature stability for a Schottky contact to unleash the full potential of diamond and compare these requirements to the available experimental data. Additionally, we present the optimal performance of diamond Schottky barrier diodes and discuss their future prospects. Our results show that optimal performances of diamond Schottky barrier diodes are technologically accessible for the ultra-high voltage range (<5 kV) and moderately high temperature (550 K) and particularly efficient but more challenging at the high voltage range (1 kV). Lastly, we demonstrate that diamond Schottky barrier diodes are the most performing alternative at high temperature among wide band-gap semiconductors.