We report on a recently-observed difference in nitrogen doping during the growth of homoepitaxial films grown on on-axis 4H-SiC (SiC-silicon carbide) substrates patterned with arrays of mesas. In particular, the doping of webbed cantilevered regions that grew laterally from the tops of mesas free of axial screw dislocations was observed to be significantly greater than solid mesas with screw dislocations that grew vertically along the [0001] c-axis. (c) 2007 Elsevier B.V. All rights reserved.