Effects of incomplete ionization on forward current-voltage characteristics of p-type diamond Schottky barrier diodes based on numerical simulation

Abstract

The forward current-voltage characteristics of p-type diamond pseudo-vertical Schottky barrier diodes are investigated via numerical simulation. Impact ionization decrease the hole concentration of the p- drift layer from 10(15) to 10(14) cm(-3) at 300 K, thereby increasing the forward voltage drop and on-resistance. When we consider an incomplete ionization with increasing temperature, the increase in the hole concentration is more dominant than the enhanced phonon scattering, thereby resulting in an increasing forward current. We modified the Ohmic contact for both metallic conduction at the p+ layer and incomplete ionization at the p- drift layer. The Baliga figure-of-merit of the device with and without incomplete ionization is 25 and 192 MW cm(-2), respectively. Incomplete ionization should be considered in the numerical study of diamond power devices.