The effect of an underlying SiO2 layer upon the lateral solid-phase epitaxy of amorphous material was investigated by comparing the characteristics of samples with, and without, an underlying SiO2 layer. In the case of lateral solid-phase epitaxy, with an underlying SiO2 layer, which changed from {110} to {111} facet growth, high-density crystal defects (most of which were dislocations) were detected; especially in the {111} facet growth region. The formation of {111} facets was caused mainly by high densities of dislocations which were incorporated by the relaxation of stresses which originated from the retardation of Si atom arrangement. In the case of lateral solid-phase epitaxial material without an underlying SiO2 layer, a few dislocations were detected only on the lower side of the layer. The density of crystal defects did not increase during lateral solid-phase epitaxy because the change from {110} to {111} facet growth was suppressed. It was concluded that the removal of an underlying SiO2 layer before annealing markedly reduced the number of crystal defects which formed during lateral solid-phase epitaxy, and halted facet growth changes from {110} to {111}.

Y.Morimoto, S.Nakanishi, N.Oda, T.Yamaji, H.Matuda, H.Ogata, K.Yoneda: Journal of the Electrochemical Society, 1994, 141[1], 188-92