Aluminum nitride substrate growth by halide vapor transport epitaxy

High-quality AlN layers with thickness up to 50 pm have been grown by HVTE at growth rates up to 60 mum/h at deposition temperatures of 1000-1100degreesC in the pressure range of 50-760 Torr. The HVT process uses an aluminum chloride amine adduct as the aluminum source and ammonia for the nitrogen. This new technique eliminates the main difficulties of the conventional HVPE growth, where aluminum oxidation and the strong reactivity of aluminum chloride with quartz create the potential for oxygen contamination. The crystalline layer quality as determined by X-ray rocking curve measurement shows FWHM of 300-900 and 500-1300 arcsec for (0 0 2) and (1 0 2) planes, respectively. (C) 2002 Elsevier Science B.V. All rights reserved.