A theoretical and experimental analysis was made of strain relaxation in SiGe/Si(110) heterostructures. It was shown that, above a certain composition, the critical thickness for edge (a/6)<112> Shockley partial dislocations was less than that for 60° (a/2)<110> total dislocations. The net stress was greater on (a/6)<112> edge dislocations for epilayers which were thinner than the critical value, but was greater on 60° (a/2)<110> dislocations for thicknesses which were greater than the critical value. From the sensitive dependence of this critical value upon the stacking fault energy, it was deduced that the latter was equal to 65mJ/m2 in the case of Si0.7Ge0.3.

Quantitative Analysis of Strain Relaxation in GexSi1-x/Si(110) Heterostructures and an Accurate Determination of Stacking Fault Energy in GexSi1-x Alloys. R.Hull, J.C.Bean, L.J.Peticolas, D.Bahnck, B.E.Weir, L.C.Feldman: Applied Physics Letters, 1992, 61[23], 2802-4