[18p-P14-1~19] 15.6 Group IV Compound Semiconductors (SiC)

[18p-P14-16] Nitrogen doping of 4H-SiC MOS interface after ¹⁵NO post-oxidation anneal characterized by electron-spin-resonance (ESR) spectroscopy

〇Takahide Umeda¹, Mitsuru Sometani², Shinsuke Harada² (1.Univ. of Tsukuba, 2.AIST)

Keywords:SiC-MOS interface, post nitridation anneal, nitrogen doping

Nitridation processes on SiC-MOS interfaces (e.g., using NO post-oxidation anneal) are known as the standard process for improving performances of SiC-MOSFETs. Some previous studies pointed out that nitrogen donors are formed in the channel region after the nitridation, raising the channel mobilities of SiC-MOSFETs. In this work, we performed ¹⁵NO post-oxidation anneal and evaluated ¹⁵N-donor densities using electron-spin-resonance (ESR) spectroscopy. As a result, the densities of ¹⁵N donors were estimated to be below our detection limit (< 2e11 cm^-2). Instead, we observed a drastic reduction in carbon interface defects, which amounts to ~ 3e12 cm^-2.