Equilibrium shapes and energies of coherent strained InP islands

The equilibrium shapes and energies of coherent strained InP islands grown on GaP have been investigated with a hybrid approach that has been previous ly applied to InAs islands on GaAs. This combines calculations of the surfa ce energies by density-functional theory and the bulk deformation energies by continuum elasticity theory. The calculated equilibrium shapes for diffe rent chemical environments exhibit the {101}, {111}, {(1) over bar (1) over bar (1) over bar} facets and a (001) top surface. They compare quite well with recent atomic-force microscopy data. Thus in the InP/GaInP system a co nsiderable equilibration of the individual islands with respect to their sh apes can be achieved. Rie discuss the implications of our results for the O stwald ripening of the coherent InP islands. [S0163-1829(99)15147-6].