Direct observation of stacking fault nucleation in the early stage of ZnSe/GaAs pseudomorphic epitaxial layer growth

The nucleation of stacking faults in the initial stage of growth of ZnSe/GaAs(001) epilayers has been studied by high-resolution transmission electron microscopy. Stacking faults have been observed to nucleate on the {111} planes on the slopes of ZnSe islands and hang over the adjacent (001) surface. The image details of a V-shaped fault originating from a sharp tip at a later stage of growth is in good agreement with the simulated image of stacking faults emerging from a dimer array of three chains. This gives support to residual dimer array on the 2x1 reconstructed (001) surface as the origin of stacking faults in ZnSe epilayers. (C) 2000 American Institute of Physics. [S0003-6951(00)02744-3].