Post-growth thermal processing at 1200 to 1400C was shown to improve markedly the quality of thin (200nm) films which had been grown, using molecular beam epitaxy, onto SiC substrates. A comparison of both on-axis (00•2) and off-axis (10•2) X-ray diffraction peaks reflected this improvement. Cross-sectional transmission electron micrographs confirmed a reduction in the incidence of dislocations and grain boundaries, while plan-view micrographs demonstrated that threading defect densities could be reduced to about 3 x 108/cm2 by annealing.

Defect Annihilation in AlN Thin Films by Ultra-High Temperature Processing Z.Y.Fan, G.Rong, N.Newman, D.J.Smith: Applied Physics Letters, 2000, 76[14], 1839-41