SELF-ORGANIZED GROWTH OF ZNTE NANOSCALE ISLANDS ON (001)GAAS

The Stransky-Krastanow metalorganic vapor phase epitaxy growth of self -organized ZnTe islands on homoepitaxial (001)GaAs is demonstrated. Th e -7.4% lattice mismatch of the ZnTe/GaAs heterostructure leads to a s train-driven distribution of nanoscale ZnTe islands on top of a two-di mensionally (2D) grown wetting layer. Atomic force microscopy and Ruth erford backscattering spectrometry are used to determine the island di mensions and the thickness of the wetting layer. The density of the is lands, their average diameter, and aspect ratio turn out to be about 5 20 mu m(-2), 13.6 nm, and 0.20, respectively, for a 1.2 ML thick 2D la yer. Furthermore, the average aspect ratio of the islands decreases by increasing the thickness of the wetting layer, as expected by the pro gressive extinction of the strain-driven island nucleation. (C) 1998 A merican Institute of Physics.