[20a-E311-1~11] 15.6 Group IV Compound Semiconductors (SiC)

[20a-E311-11] Influence of non-uniform interface defect distribution on channel mobility in SiC MOSFET — Study based on local DLTS measurement and device simulation —

〇Kohei Yamasue¹, Yuji Yamagishi¹, Yasuo Cho¹ (1.Tohoku Univ.)

Keywords:local DLTS, scanning nonlinear dielectric microscopy, SiC

Recently, a novel scanning probe microscopy method called local DLTS has been developed for the nanoscale evaluation of interface state density (D_it) distribution at the insulator-semiconductor interfaces. By using local DLTS, we have shown that D_it at the SiO₂/SiC interfaces has non-uniform in-plane distribution. In this talk, we discuss the influence of non-uniform D_it distribution on the channel mobility of SiC MOSFET using 3D device simulation which incorporates D_it distribution actually measured by local DLTS. Our results show that the non-uniformity of D_it persisting even after the nitridization of the interfaces significantly reduces the channel mobility of SiC MOSFET.