[15p-C302-1~18] 15.6 Group IV Compound Semiconductors (SiC)

△ [15p-C302-16] Shunt current in 4H-SiC mesa pn diodes caused by post-oxidation nitridation of SiO₂ passivation

〇Satoshi Asada¹, Tsunenobu Kimoto¹, Jun Suda¹ (1.Kyoto Univ.)

Keywords:SiC diode, Post-oxidation nitridation, Band bending

It is known that surface passivation with post-oxidation nitridation on a mesa sidewall of a 4H-SiC p-n diode induces shunt current, a ledge in forward current-voltage (I-V) characteristics. In this work, the origin was studied by adopting various surface passivation processes on 4H-SiC mesa p-n diodes. It is shown that the shunt current can be qualitatively explained by considering band bending along the mesa sidewall, which results from fixed charge introduced by post-oxidation nitridation.