Theoretical analysis of tunneling current in 4H-SiC Schottky barrier diodes under reverse-biased conditions based on the complex band structure

Abstract

The tunneling current in heavily doped 4H-SiC Schottky barrier diodes under reverse-biased conditions is calculated based on the complex band structure by the empirical pseudopotential method. When the experimental values for effective mass and barrier height are assumed, the calculation result by the approximation assuming a parabolic complex band significantly underestimates the experimental tunneling current. In contrast, the calculation using the non-parabolic complex band by the empirical pseudopotential method we propose in this study reproduces the experimental result with better accuracy. These results imply that it is important to consider the non-parabolicity of the complex bands when calculating the tunneling current.