Stability of interfacial dislocations in (001) silicon surfacial grain boundaries

Ultrathin (001) silicon films bonded onto (001) silicon wafers, which form "surfacial grain boundaries" have been investigated by transmission electron microscopy. The samples were obtained by bonding one silicon-on-insulator (SOI) structure with one silicon wafer. After the removal of the SOI substrate, the remaining top thin film was further reduced by a thermal oxidation. Samples with a given film thickness selected in the 200 nm to 10 nm range were obtained. For very thin films, the thinning procedure can induce a mobility of the interfacial dislocations. To keep the interfaces stable, we have replaced the thermal oxidation thinning by a low-temperature chemical etching. (C) 2002 American Institute of Physics.