Temperature-Dependent Electrical Characteristics and Extraction of Richardson Constant from Graphitic-C/n-Type 6H-SiC Schottky Diodes

Energetically deposited graphitic carbon (C) is known to form high-endurance rectifying contacts to a variety of semiconductors. Graphitic contacts to n-type 6H-SiC have demonstrated current rectification ratios (at ± 1.5 V) up to 1:106. In this article, the current voltage temperature (I-V-T) characteristics of these devices are examined to reveal more detail on the junction/barrier properties that are critical to performance. Analysis of the I-V-T characteristics and disparity between barrier heights extracted from the I-V-T data and C-V data show inhomogeneity in the contacts and this has been quantified. Accounting for the inhomogeneity, the homogeneous Richardson constant of the n-type 6H-SiC can be extracted from the I-V-T data, and this value agrees with the reported theoretical value.