INVESTIGATION OF DEFECT PASSIVATION IN 4H-SiC USING HYDROGEN PLASMA AND EFFECT OF POST ANNEALING

摘要

In this paper, it was found that the electrically active defects in 4H-SiC single crystal could be passivated by hydrogen at low temperature. Hydrogen was introduced by plasma treatment and its effects were characterized by deep level transient spectroscopy. Hydrogen passivation of defects was indirectly confirmed by current-voltage curve, resulting in the reduction of the leakage current level. However, plasma-induced defects were formed by the bombardments of energetic particles to the crystal lattice, but they were annealed out at low annealing temperature of 400～500℃. From the above results, it can be concluded that these defect levels are related to the carbon vacancy-type defects. And it was revealed by Ⅰ-Ⅴ measurement that hydrogen passivation of defects was maintained up to 500℃.