[16a-P5-1~15] 15.6 Group IV Compound Semiconductors (SiC)

[16a-P5-12] An analysis of in-plane defect distribution of carbon-related defects in dry-oxide C-face 4H-SiC MOSFET

〇Yohei Kagoyama¹, Mitsuo Okamoto², Hironori Yoshioka², Shinsuke Harada², Takahiro Yamasaki³, Takahisa Ohno³, Takahide Umeda¹ (1.Univ. of Tsukuba, 2.AIST, 3.NIMS)

Keywords:MOSFET, interfacial defect, ESR

Up to date, we have investigated carbon-related interfacial defects in C-face dry-oxide 4H-SiC MOSFETs using electrically-detected-magnetic-resonance (EDMR) spectroscopy. In the observed EDMR signal, we found a strong signature of “dipolar broadening” which indicates a magnetic-dipole-dipole interaction between high-density electron spins. In this work, we analyze the dipolar broadening of the EDMR signal using a numerical simulation. The density of electron spins in C-face dry-oxide MOS interfaces was estimated to be 6×10¹³ cm^-2, based on the linewidth of the EDMR signal. On the contrary, we estimated the interface-state density to be 5×10¹² cm^-2 on the basis of current-voltage characteristics of the MOSFET at 500 to 570 K. We simulated several types of electron-spin distributions that satisfied the above experimental results. Finally, we numerically simulated the dipolar broadening for each distribution, and discussed the most probable distribution.