The selective epitaxial growth of Si through windows in SiO2 was used to fabricate Si-on-insulator structures by means of epitaxial lateral overgrowth. Under suitable conditions, this process yielded a continuous epitaxial film over buried oxides. However, an unique so-called seam-like defect was observed at the interfaces where 2 lateral growth fronts met. A series of threading dislocations along the merging interface were identified as making up the structure of the seam defect. Epitaxial lattice mismatch at certain juncture points was suggested to have initiated the dislocations. Accumulated strains in the epitaxial film, which arose from oxide surface perturbations or interfacial stresses, were expected to be possible sources of the juncture mismatch.

Y.C.Shih, J.C.Lou, W.G.Oldham: Applied Physics Letters, 1994, 65[13], 1638-40