Electrical defects in grown oxide on SiC and from the oxide/SiC interface

SiC MOS capacitors were fabricated in order to evaluate both the electrical defects from the oxide/SiC interface and the oxide charges from the thermally grown oxide. Two circular active areas were designed in order to be further tested as a differential gas sensor. The effective oxide charge was determined based on the deviation of experimental C-V curves from ideal ones, leading to a value of 4.2 x 10
¹²
cm
^-2
. The interface states' density was calculated based on the Terman method, demonstrating a decrease from near the SiC conduction band (8.5 × 10
¹²
cm
^-2
eV
^-1
) to deeper inside the gap (1.6 × 10
¹²
cm
^-2
eV
^-1
).