Single crystals of AlN have been grown by seeded (on SiC substrates) and unseeded (spontaneous nucleation) sublimation techniques. Tantalum carbide coated graphite crucibles were used. Temperature gradient and source-substrate distance have been found to be the most influencing parameters of crystal growth. AlN crystals of maximum dimension 12 mm (length) × 10 mm (width) × 300 μm (thickness) were grown on 6H-SiC substrates and the best (0002) oriented crystal showed an XRD omega rocking curve FWHM of 4.81 arcmin. AlN nucleated as independent hexagonal islands and coalesced as growth progressed on. Growth rate of AlN grown on C-face SiC has been found to be higher than that on Si-face SiC. Tantalum carbide coated crucibles have been found to be better suited for AlN growth as the impurity incorporation in to the crystals due to crucible was very less. Spontaneously nucleated crystals exhibited an incompleted pyramid-like structure with (1010) and (1100) as their prominent faces.