Defect-mediated island formation in Stranski-Krastanov growth of Ge on Si(001)

Abstract
We have observed macroscopic island (macroisland) formation in Stranski-Krastanov growth of Ge on Si(001) surfaces under various growth conditions using transmission electron microscopy. The interplay between surface morphological evolution and defect formation during growth was revealed. We show that the nucleation of macroislands is predominantly heterogeneous. Furthermore, evidence is presented that macroisland formation is mediated by a particular defect which results from the coalescence of small faceted islands. DOI: http://dx.doi.org/10.1103/PhysRevLett.71.4007 © 1993 The American Physical Society