Epitaxial Growth of Cu Thin Films on (111)Si at Room Temperature

Abstract

AbstractEpitaxial growth of Cu thin films on atomically cleaned (111)Si has been studied by transmission electron microscopy (TEM), x-ray diffractometry (XRD) and Auger electron spectroscopy (AES). An interface compound, CuSix with x= 11.2 to 14 at.%, was observed to be present at the Cu/Si interface. Interfacial dislocations at the silicide/Si interface were identified to be of edge type with 1/2<110> Burgers vectors. η“-Cu3Si was found to form in samples annealed at 200 °C for 1 h. Solid phase epitaxial growth of silicon on (111)Si was observed to occur at a temperature as low as 200 °C. Polycrystalline η”-Cu3Si is the only phase present in samples annealed at 200–800 °C. In samples annealed at or higher than 850 °c, a mixture of η′-Cu3Si and η“-Cu3Si were found to be present.