In this paper we have implemented a recently proposed direct-measurement technique to characterize near-interface oxide traps (NITs) in SiC MOS capacitors with gate oxides obtained by four different processes. This measurement technique enables characterization of NITs with energy levels above the bottom of the conduction band, which are active in the accumulation mode of MOS capacitors on N-type SiC and in the strong inversion of N-channel MOSFETs. The measurements revealed that annealing in nitric oxide of thermally grown oxides in dry oxygen removes NITs that are further away from the SiC surface, but it leaves a defect with energy levels located between 0.13 eV and 0.23 eV above the bottom of conduction band. The oxides grown in pure nitric oxide exhibit NITs with energy levels above 0.2 eV. The measurements also show that low-temperature oxide deposition and subsequent annealing in nitric oxide resulted in the lowest density of NITs.

在本文中，我们已经实施了一种最近提出的直接测量技术，以通过四种不同工艺获得的栅氧化物来表征SiC MOS电容器中的近界面氧化物陷阱（NIT）。这种测量技术可以表征能级高于导带底部的NIT，这些NIT在N型SiC上的MOS电容器的累积模式下以及在N沟道MOSFET的强反转中起作用。测量结果表明，在干燥氧气中的热生长氧化物的一氧化氮中进行退火可以去除更远离SiC表面的NIT，但会留下缺陷，其能级位于导带底部以上0.13 eV至0.23 eV之间。在纯一氧化氮中生长的氧化物表现出能级高于0.2 eV的NIT。