High-resolution transmission electron microscopic analysis of porous silicon∕silicon interface

Abstract

From high-resolution transmission electron microscopy, a strong contrast was observed in the interface between porous silicon and the silicon substrate, which was associated with the presence of high stress. It was determined that stress in the porous silicon∕Si interface is caused by dislocations and that lattice matching occurs through pairs of edge-dislocations. In addition, a high density of dislocations was also observed in the neighborhood of the Si nanocrystals that compose porous silicon. From the experimental results, a mechanism for the formation of porous silicon is proposed.