Epitaxial growth of 4H–SiC(0 3 3̄ 8) and control of MOS interface

Homoepitaxial growth on 4H–SiC(0 3 3̄ 8) by chemical vapor deposition (CVD) and the MOS interface have been investigated. Unintentionally-doped 4H–SiC(0 3 3̄ 8) epilayers showed a low background doping concentration of 3×1014 cm−3 and a low trap concentration of 8×1011 cm−3. Almost complete (∼100%) closing of micropipes was realized, although some of very large (>3 μm) micropipes were threading into epilayers. Conductance measurements on n-type MOS capacitors revealed that the interface state density (Dit) near the conduction-band edge is lower on 4H–SiC(0 3 3̄ 8) than on 4H–SiC(0 0 0 1). Higher channel mobility was obtained for inversion-type (0 3 3̄ 8) MOSFETs, compared to (0 0 0 1) MOSFETs.