Formation of an extended CoSi2 thin nanohexagons array coherently buried in silicon single crystal

REQUEJO, F. G.; KELLERMANN, G.; A. F. CRAIEVICH; GIOVANETTI, L. J.; DOS SANTOS CLARO, P. C.; MONTORO, L. A.; RAMIREZ, A.J.

Campinas, SP, Brazil.

Congreso; 22ª Reunião Anual de Usuários; 2012

LNLS

A Co-doped silica film was deposited on the surface of a Si(100) wafer and isothermally annealed at 750C. This thermal treatment induced the formation of spherical Co nanoparticles embedded in the silica ¯lm and a few atomic layer thick CoSi2 nanoplatelets within the Si(100) wafer. The structure, morphology and spatial orientation of the CoSi2 nanoplatelets incrusted in the Si crystal were characterized by Transmission Electron Microscopy (TEM) and synchrotron Grazing-incidence-Small-angle X-ray scattering (GISAXS) techniques. The experimental results indicate that the CoSi2 nanoplatelets exhibit a nearly regular hexagonal shape and a uniform thickness. The CoSi2 nanostructures lattice is coherent with the Si lattice and each of them is parallel to one of the four planes belonging to the 111 crystallographic form of the host lattice, indicating a crystal growth with a Si111 habit plane. Furthermore, in order to study the growth kinetics of the formation of these nanostructures, in situ experiments were performed, annealing the samples from room temperature to 750C and following the evolution of the GISAXS signal in the process. TEM studies and GISAXS experiments were performed at the Brazilian Nanotechnology National Laboratory (LME-LNNano) and XRD2 X-ray di®raction beam line of the Brazilian Synchrotron Light Laboratory (LNLS), respectively, in Campinas, Brazil.