Sublimation growth and atmospheric pressure CVD growth of 6H-SiC was conducted on (11 (2) over bar0) substrates, and the effect of nitrogen was investigated by growing the crystals with and without intentional nitrogen doping. Nitrogen had a powerful effect to improve the crystal quality on crystal growth of SiC on (11 (2) over bar0) substrates. In CVD growth, flat surfaces without step bunching was obtained with intentional nitrogen doping. In sublimation growth, hollow core defects were generated, and pits were observed on the surface. Both the size and the density of the pits were decreased by growing the crystals in nitrogen atmosphere. High nitrogen concentration in the crystals resulted in higher evaporation rate and higher surface flatness, and thus crystals with low defect density was grown on (11 (2) over bar0) substrates by growing the crystals with intentional nitrogen doping. Lower C/Si ratio in the vapor phase was also important to keep the surface flat.