Nam, O., Zheleva, T.S., Bremser, M.D. et al. Journal of Elec Materi (1998) 27: 233. doi:10.1007/s11664-998-0393-8
Lateral epitaxial growth and coalescence of GaN regions over SiO2 masks previously deposited on GaN/AlN/6H-SiC(0001) substrates and containing 3 µm wide rectangular windows spaced 7 µm apart have been achieved. The extent and microstructural characteristics of these regions of lateral overgrowth were a complex function of stripe orientation, growth temperature, and triethylgallium (TEG) flow rate. The most successful growths were obtained from stripes oriented along 〈1 \( < 1\bar 100 > \)00〉 at 1100°C and a TEG flow rate of 26 µmol/min. A density of ∼109 cm−2 threading dislocations, originating from the underlying GaN/AlN interface, were contained in the GaN grown in the window regions. The overgrowth regions, by contrast, contained a very low density of dislocations. The surfaces of the coalesced layers had a terrace structure and an average root mean square roughness of 0.26 nm.