ABSTRACT
Wide-bandgap semiconductors offer substantial benefits for electronic devices operating at extreme conditions such as high temperature, high power, and high speed. Silicon Carbide (SiC) is attractive because of its high critical breakdown field, high thermal conductivity, and high electron saturation velocity. In addition to these important material characteristics, the high-quality thermal oxide on SiC enables metal–oxide–semiconductor field-effect transistors (MOSFETs) for power applications. This chapter discusses the effects of Nitrogen (N) on electron trapping at silicon dioxide (SiO2)/SiC interfaces as revealed by temperature-dependent, high-frequency C–V and transient capacitance spectroscopy techniques. Two different methods of introducing N at the SiO2/SiC interface were used: postoxidation Nitric Oxide (NO) annealing and ion implantation of N near the SiC surface prior to thermal oxidation. Although a detailed understanding of the mechanism of N passivation remains elusive, a reduction of the interface state density using the NO annealing process was the breakthrough that led to the recent commercialization of 4H-SiC power MOSFET circuits.
