Influence of the Existence of an Underlying SiO2 Layer on the Lateral Solid‐Phase Epitaxy of Amorphous Silicon

Abstract

The influence of the existence of an underlying layer on the lateral solid‐phase epitaxy (L‐SPE) of amorphous Si was investigated by comparing the characteristics of L‐SPE with and without an underlying layer. For the L‐SPE with an underlying layer which had a change 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 is caused primarily by high density dislocations incorporated by relaxation of the stress which originates from the retardation of Si atom rearrangement. For the L‐SPE without the underlying layer, a few dislocations were detected only in the lower side of the L‐SPE layer. The density of crystal defects did not increase during the L‐SPE since the change from {110} to {111} facet growth was suppressed. Thus, we confirmed that removal of the underlying layer prior to annealing for L‐SPE dramatically reduces the crystal defects formed during L‐SPE and halts the facet growth change from {110} to {111}.