The structure of an ultra-thin epitaxial Ge layer during in situ deposition onto a Si(001) surface was investigated. Peaks arising from the 2 x 1 reconstruction disappeared at ML coverages. The layer was epitaxial with respect to the substrate up to a coverage of ≈5Ml, beyond which the strained layer relaxes gradually. At a coverage of 10ML the lateral strain was reduced to 2.2% compared with 4.0% in the unrelaxed layer.

The Initial Stages of Growth of Ge on Si(001) Studied by X-Ray Diffraction. A.A.Williams, J.E.Macdonald, R.G.van Silfhout, J.F.van der Veen, A.D.Johnson, C.Norris: Journal of Physics - Condensed Matter, 1989, 1[SB], 273-4