[20p-E311-1~17] 15.6 Group IV Compound Semiconductors (SiC)

[20p-E311-12] Expansion of Shockley Stacking Faults in 4H-SiC Epitaxial Layer by Forward Bias Current or Ultraviolet Irradiation

〇Kazumi Takano¹, Yoshihiko Ohsaki¹, Yasuyuki Igarashi¹ (1.ITES)

Keywords:Silicon carbide, Shockley-type stacking fault, Stacking fault expansion

The expansion of Shockley-type stacking faults (SSFs) in an epitaxial layer results from forward bias current through the parasitic body diode in 4H-SiC MOSFET. It is known that the SSF expansion also occurs under ultraviolet (UV) irradiation. Similarity and difference between the SSF expansion by forward bias current and that by UV irradiation are investigated using commercial SiC MOSFET modules. The SSF expansions are shaped to right triangles in both cases only when the SSFs are expanded from the basal plane dislocation (BPD) which resides inside an epitaxial layer or extends to an epitaxial layer surface. However, the SSF expansions from the BPD near a substrate, become bar shapes by forward current, while become polygons by UV irradiation.