The hetero-epitaxial lateral overgrowth technique, using grooved sapphire (00•1) and (11•0) SiC(00•1)Si and Si(111) substrates, was used to prepare AlxGa1-xN monocrystalline films (with x-values of up to 0.13) having a low dislocation density. Straight grooves of these substrates were aligned parallel to the <1¯1•0> or <11•0> directions of AlxGa1-xN. Neither a selective growth mask nor patterned GaN single crystal films were used. Dislocation densities of less than about 106/cm2 were detected via plan-view transmission electron microscopy.

Low Dislocation-Density GaN and AlxGa1-xN Grown on Grooved Substrates. S.Sano, T.Detchprohm, S.Mochizuki, S.Kamiyama, H.Amano, I.Akasaki: Journal of Crystal Growth, 2002, 235[1-4], 129-34