Barrier Inhomogeneities of Mo Schottky Barrier Diodes on 4H-SiC

In this work we present the results of electrical characterization of 4H-SiC power Schottky diodes with a Mo metal barrier for high power applications. A comparison between different Schottky Barrier Height (SBH) evaluation methods (capacitance-voltage and current-voltage measurements), together with the comparison with other authors' works, indicates that thermionic current theory is the dominant transport mechanism across the barrier from room temperature (RT) to 450K, while at T < 300K some anomalies in J-V curves appear and SBH and ideality factor significantly change their values. These deviations from ideality are attributed to Schottky barrier inhomogeneities. In particular, a model based on two SBHs seems appropriate to properly describe the electrical behavior of our devices.