Dielectrics in Silicon Carbide Devices: Technology and Application
Anthony O’Neill, Oliver Vavasour, Stephen Russell, Faiz Arith, Jesus Urresti, Peter Gammon
Formation of dielectric layers on SiC is a key feature of device processing technology. Achieving high mobility SiC MOSFETs is dependent on solving challenges within gate stack formation, where the dielectric plays a central role. Dielectrics also play a key role in surface passivation of SiC devices. This chapter reviews the main dielectrics that are used in SiC devices. The most commonly used dielectrics in electronic devices are SiO2 and Si3N4 and so these are introduced first, followed by high-κ dielectrics (i.e. dielectrics with higher permittivity than Si3N4). The methods of dielectric deposition are discussed before focusing on SiC thermal oxidation. Different parameters of the oxidation process and post-oxidation annealing, which have an impact on oxide quality and the formation of residual carbon in the SiO2/SiC interface, are evaluated. Efforts to improve electron mobility in SiC MOSFETs using a variety of dielectric layer formation techniques are reviewed, indicating where progress has been made. Issues surrounding SiC surface passivation by dielectrics are also discussed.
Silicon Oxide, High-κ Dielectrics, MOSFET, Gate Oxide, Surface Passivation, Post Oxidation Annealing, Field Effect Mobility, Silicon Nitride
Published online 2/15/2020, 44 pages
Citation: Anthony O’Neill, Oliver Vavasour, Stephen Russell, Faiz Arith, Jesus Urresti, Peter Gammon, Dielectrics in Silicon Carbide Devices: Technology and Application, Materials Research Foundations, Vol. 69, pp 63-106, 2020
Part of the book on Advancing Silicon Carbide Electronics Technology II
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