SELF-ORGANIZED INAS ISLANDS ON (100)-INP BY METALORGANIC VAPOR-PHASE EPITAXY

The effects of growth temperature, InAs deposition thickness and depos ition rate on the areal density, size, uniformity and spatial distribu tion of self-organized InAs nanoscale islands grown on exact and vicin al (100) InP substrates by metalorganic vapor-phase epitaxy are invest igated in detail by AFM. At 500 degrees C, the island density is found to increase as the InAs deposition thickness is increased, while the average island size decreases slightly. At growth temperatures above 5 00 degrees C, larger inhomogenous islands also appear. Decreasing the deposition rate increases the island density and substrate coverage. T he unintentional As/P exchange is found to have a significant influenc e on island formation by producing excess material for the islands. Lo w-temperature photoluminescence from the recombination of carriers in the buried InAs islands is observed in the 1.4-1.8 mu m spectral regio n. (C) 1997 Elsevier Science B.V.