Formation of low-index facets in Ga0.2In0.8As and InAs islands on a InP(113)B substrate

Strained ${\mathrm{Ga}}_{\mathrm{0.2}}{\mathrm{In}}_{\mathrm{0.8}}\mathrm{As}$ and InAs islands were grown on a InP(113)B substrate by gas source molecular beam epitaxy and examined by transmission electron microscopy and atomic force microscopy. The islands are mainly bounded by the low-index facets {001}, {111}B, and {110} [inclination with respect to the (113)B surface of 25°, 29°, and 31°, respectively]. Some of the consequences of the substrate orientation on the island shape and formation are discussed.