Transport properties at 3C-SiC interfaces

Abstract

For years cubic (3C) silicon carbide (SiC) has been believed to be a very promising wide bandgap semiconductor for high frequency and high power electronics. However, 3C-SiC is fraught with large concentrations of various defects, which have so far hindered the achievement of the predicted properties at a macroscopic level. These defects have properties that are inherently nanoscale and that will have a strong influence on the electrical behavior of the material, particularly at interfaces commonly found in electronic devices. The aim of this thesis is then to understand and overcome some of the challenges faced for fabrication of electronic devices in this material, by studying the nanoscale transport properties at 3C-SiC interfaces. In this way, the non-ideal macroscopic behavior of fabricated devices can be better understood and ultimately improved. To this end, characterization approaches that are able to distinguish morphological, electrical and structural features at the nanoscale are essential. Most attention is given to scanning probe microscopy based methodologies, able to physically probe the sample and image tip-sample interactions of morphological and electrical nature at the nanoscale. The topics of investigation include the major concerns related to the electronic transport at metal/SiC interfaces and the non ideal behavior in metal/oxide/SiC systems.