Free Standing AlN Single Crystal Grown on Pre-Patterned and In Situ Patterned 4H-SiC Substrates
Free standing AlN wafers were grown on pre-patterned and in situ patterned 4H-SiC substrates by a physical vapor transport method. It is based on the coalescence of AlN microrods, which evolve from the apex of SiC pyramids grown on the SiC substrate during a temperature ramp up for in situ patterned substrate and SiC pyramids formed by reactive ion etching (RIE). This process yields stress-free (according XRD and Raman results) AlN single crystals with a thickness up to 400 µm and low dislocation density.
Anton J. Bauer, Peter Friedrichs, Michael Krieger, Gerhard Pensl, Roland Rupp and Thomas Seyller
G. R. Yazdi et al., "Free Standing AlN Single Crystal Grown on Pre-Patterned and In Situ Patterned 4H-SiC Substrates", Materials Science Forum, Vols. 645-648, pp. 1187-1190, 2010