INGAAS ISLAND SHAPES AND ADATOM MIGRATION BEHAVIOR ON (100)GAAS-SURFACES, (110)GAAS-SURFACES, (111)GAAS-SURFACES, AND (311)GAAS-SURFACES

The evolution of InGaAs island formation on (100), (110), (111), and ( 311) GaAs substrates was studied by atomic force microscopy. In additi on to determining the growth mode, shape, average size and distributio n of InGaAs islands on each orientation, measurement of the saturation island densities enabled an estimation of effective group III adatom surface diffusion lengths. Small lens-shaped islands in addition to la rger faceted islands were formed on (100) and (311) surfaces, while tr apezoidal and triangular islands were obtained on (110) and (111)B ori entations, respectively. Adatom diffusion lengths on these surfaces we re found to range from 0.06 mu m on(311)B to 3 mu m on (111)B. (C) 199 8 American Institute of Physics.