The role of deep level traps in barrier height of 4H–SiC Schottky diode

This paper presents a discussion about the influence of deep level defects on the height of Ni–Si based Schottky barriers to 4H–SiC. The defects were characterized by deep level transient spectroscopy (DLTS) in a wide range of temperatures (78–750 K). The numerical simulation of barrier height value as a function of dominant defect concentration was carried out to estimate concentration, necessary to “pin” Fermi level and thus significantly influence the barrier height. From comparison of the results of simulation with barrier height values obtained by capacitance–voltage (C–V) measurements it seems that dominant defect in measured concentration has a very small impact on the barrier height and on the increase of reverse current.