[16a-C302-1~12] 15.6 Group IV Compound Semiconductors (SiC)

▼ [16a-C302-10] A Distributed Model for Near-Interface Traps in 4H-SiC MOS Capacitors

〇(D)Xufang Zhang¹, Dai Okamoto¹, Tetsuo Hatakeyama², Mitsuru Sometani², Shinsuke Harada², Ryoji Kosugi², Noriyuki Iwamuro¹, Hiroshi Yano¹ (1.U. Tsukuba, 2.AIST)

Keywords:4H-SiC MOS, near-interface traps, distributed model

Near-interface traps (NITs) are one of the most harmful oxide defects locating near the interface of SiO₂/4H-SiC, which leads to the poor properties of 4H-SiC MOSFETs. However, currently, there is no good approach to estimate the density and distribution of the NITs because it is hard to distinguish the NITs and fast interface states. In this work, we established a distributed model to investigate the NITs based on the tunneling mechanism in the strong accumulation region. It yields frequency-dependent capacitance and conductance in agreement with the experimental results of dry oxidation and NO-annealed samples. Based on the proposed model, we estimated the density distribution of the NITs against the tunneling depth.