Selective epitaxial mesas of SiC were successfully grown on masked 4H-SiC (0 0 0 1) and (1 1 (2) over bar 0) substrates using a carbon mask by a CVD method. The carbon mask was removed by thermal oxidation without surface degradation, resulting in the successful formation of SiC epitaxial mesa structures on SiC substrates. The influences of crystal orientation, "step-flow growth" on SiC mesas, and polytypes of grown layers have been investigated. The external lateral growth on the carbon mask was observed along the <1 1 (2) over bar 0 > direction on the off-axis (0 0 0 1) and along the < 0 0 0 1 > direction on the on-axis (1 1 (2) over bar 0) 4H-SiC substrates. Both on the off-axis (0 0 0 1) and the on-axis (1 1 (2) over bar 0) substrates, the main portion of epitaxial mesas is homoepitaxially grown 4H-SiC. Cross-sectional transmission electron microscopic analysis revealed that 3C-SiC existed at the upstream side of step-flow on the off-axis (0 0 0 1) substrate and in the external lateral growth region along the <0 0 0 1> direction on the on-axis (1 1 (2) over bar 0) substrate. (C) 2003 Elsevier Science B.V. All rights reserved.