Controlling 4H-SiC Schottky Barriers by Molybdenum and Molybdenum Nitride as Contact Materials

Abstract

In this paper, Schottky diodes, consisting of an n-doped 4H-silicon carbide substrate, and molybdenum and molybdenum nitride thin-film metallization, are presented. By the variation of the nitrogen amount in the molybdenum nitride thin films, we successfully manage to adjust the effective Schottky barrier height in the range 0.68-1.03 eV at room temperature. In addition, the temperature dependence of the Schottky barrier height can be influenced by the nitrogen fraction used during sputter deposition. The electrical behavior of the junctions is analyzed using current over voltage (I/V) and capacitance over voltage (C/V) measurements in a temperature range of 25 °C-300 °C and 25 °C-175 °C, respectively. The characteristics are evaluated, and typical diode parameters are extracted.

In this paper, Schottky diodes, consisting of an n-doped 4H-silicon carbide substrate, and molybdenum and molybdenum nitride thin-film metallization, are presented. By the variation of the nitrogen amount in the molybdenum nitride thin films, we successfully manage to adjust the effective Schottky barrier height in the range 0.68-1.03 eV at room temperature. In addition, the temperature dependence of the Schottky barrier height can be influenced by the nitrogen fraction used during sputter deposition. The electrical behavior of the junctions is analyzed using current over voltage (I/V) and capacitance over voltage (C/V) measurements in a temperature range of 25 °C-300 °C and 25 °C-175 °C, respectively. The characteristics are evaluated, and typical diode parameters are extracted.