THE INFLUENCE OF ISLAND-INDUCED STRAIN ON THE Si SURFACE MORPHOLOGY IN Ge-Si MULTILAYERS:A TRANSMISSION ELECTRON MICROSCOPY STUDY
THE INFLUENCE OF ISLAND-INDUCED STRAIN ON THE Si SURFACE MORPHOLOGY IN Ge-Si MULTILAYERS： A TRANSMISSION ELECTRON MICROSCOPY STUDY

Growth and ordering of coherently strained Ge-rich islands in Ge/Si single layer and multilayer systems and the influence of island arrangements on the evolution of the surface morphology of Si cap layers during deposition by low-pressure chemical vapour deposition(LPCVD) on Si(001)substrates at 700℃ have been investigated by TEM of cross-section and plan-view specimens. At distances between the Ge layers of 35-50nm, vertical order of GeSi islands is observed for Ge-Si bilayer systems and for Ge-Si multilayer systems consisting of 5 layer pairs whereas latgreement with earlier results the vertical ordering in the multilayer system can be understood as result of the elastic interaction between island nuclei forming in the layers with close islands in the elastic interaction. Characteristic for all Si surfaces are the spatial correlation between the presence of island-induced lattice strain and the appearance of arrays of larger square-shaped of the control of growth parameters and of the island-induced strain state for the evolution of the Si top layer surface morphology during LPCVD growth.