Selective Area Growth of Semipolar (20(2)over-bar1) and (20(2)over-bar(1)over-bar) GaN Substrates by Metalorganic Vapor Phase Epitaxy

We carried out the selective area growths of GaN on semipolar (20 (2) over bar1), (20 (2) over bar(1) over bar), and related non- and semi-polar GaN substrates by metalorganic vapor phase epitaxy. By changing the growth parameters and directions of the SiO2 stripe mask, the differences in GaN structures between the growths on the different substrates were investigated. In the case of the stripes parallel to a-axis, anisotropic GaN structures with (000 (1) over bar) and (10 (1) over bar1) facets were obtained for all the non- and semi-polar GaN substrates. On the other hand, in the case of the stripes perpendicular to a-axis, isotropic GaN structures were obtained for the (20 (2) over bar1) and (20 (2) over bar(1) over bar) GaN substrates. However, the GaN structures between them were quite different. After 120 min of growth, {11 (2) over bar0} and (20 (2) over bar(1) over bar) facets markedly expanded for the (20 (2) over bar1) and (20 (2) over bar(1) over bar) GaN substrates, respectively. Moreover, by exploiting the effect of growth temperature, the growth of a continuous (20 (2) over bar(1) over bar) GaN layer with voids was realized. (C) 2013 The Japan Society of Applied Physics