Fabrication and electrical characterisation of graphitic Schottky contacts to silicon, silicon carbide and gallium oxide

There is an increasing demand for power electronic devices that exhibit high current rectification and high environmental/thermal stability. This demand has driven research into novel materials that provide stable performance in extreme environments. Abundant and low-cost carbon thin film materials are potential candidates because they exhibit a wide range of electrical characteristics that depend systematically on their microstructure/bonding. More specifically, their electrical characteristics are sensitive to the ratio of diamond-like to graphitic bonding within the film. The electrical resistivity of the carbon film can be varied by many orders of magnitude within a readily accessible range of microstructures. Energetic deposition methods are one way to control the bonding ratios in carbon thin films and energetic deposition has been exploited for much of the work in this thesis.<br><br> The electronic devices that were fabricated and tested during this project were Schottky diodes. These devices, normally consisting of metal-semiconductor junctions, were instead formed between energetically deposited graphitic carbon (with high graphite like bonding fraction) and the semiconductor materials silicon, silicon carbide and gallium oxide. These materials were selected due to their proven or anticipated application in power devices. Once fabricated, the graphitic-C/semiconductor junctions were characterized micro-structurally and electrically. Subsequent analysis of the measurements revealed reasons for the excellent device performance and/or guidance for further improvements.