Published online by Cambridge University Press: 21 March 2011
High-quality 4H-SiC has been epitaxially grown on (1120) substrates by chemical vapor deposition. The physical properties of epilayers and MOS interfaces on both (1120) and off-axis (0001) substrates are elucidated. An unintentionally doped 4H-SiC epilayer on (1120) shows a donor concentration of 1×1014 cm−3 with a total trap concentration as low as 3.8×1012 cm−3. Inversion-type planar MOSFETs fabricated on 4H-SiC (1120) exhibit a high channel mobility of 96 cm2/Vs. The channel mobility decreases according to the T−2.2 dependence above 200K, indicating reduced Coulomb scattering and/or electron trapping. The superior MOS interface on (1120) originates from the much lower interface state density near the conduction band edge.