An ultra-thin Si layer (16nm) bonded onto a Si wafer was studied by means of grazing incidence X-ray diffraction. Satellite peaks around the {220} reflections coming from 2 periodic dislocation networks localized at the bonding interface were measured. These lateral superlattice peaks were explained with a simple continuum model, and their positions gave information about the tilt and twist misalignment of the 2 crystals, as well as the nature and interactions between the dislocation arrays. The square symmetry of dissociated screw dislocations (twist) and the average alignment of the mixed dislocations (tilt) were observed. The analysis of the satellite truncation rods showed that the strain field was strong enough to affect the surface, and that the dissociation of screw dislocations has to be taken into account.

Dislocation Strain Field in Ultra-Thin Bonded Silicon Wafers Studied by Grazing Incidence X-Ray Diffraction. J.Eymery, D.Buttard, F.Fournel, H.Moriceau, G.T.Baumbach, D.Lübbert: Physical Review B, 2002, 65[16], 165337 (6pp)