Self-organized growth of InAs quantum wires and dots on InP(001): The role of vicinal substrates

We have studied the self-organized growth of InAs nanostructures in an InP matrix by gas-source molecular-beam epitaxy on both nominally oriented and vicinal InP(001). Atomic force microscopy and low-temperature photoluminescence demonstrate that the off-cut direction of vicinal substrates—largely independent of growth conditions—determines the morphology of nanostructures, that is, quantum dot, quantum wire, or two-dimensional growth; whereas, on nominally oriented substrates, the morphology is very strongly dependent on the growth conditions.