|
By the methods of transmission electron microscopy and ultrasoft X-ray emission spectroscopy (USXES) the investigations of the phase composition, orientation and substructure of the surface layers formed during the pulse photon treatment of the heterostructure Si-C have been made.
The initial Si-C heterostructures were obtained by deposition of carbon films on Si(111) in a vacuum of 2•10-3 Pa. The photon treatment was made in a vacuum of 5•10-3 Pa by xenon lamp irradiation (the wave length of 0.2-1.2 µm) with sets of pulses (10-2s) during 1-2 s.
The density of the irradiation energy, coming to the sample (Ei) was changed in the range of 140-260 J•cm2. By the TEM method it has been established that at Ei ≥ 180 J•cm2 as a result of solid phase interaction of the carbon film with silicon the cubic SiC with the crystal lattice parameter a=0.436 nm is formed. The structure of all the synthesized films has been shown to be the nanocrystalline with average size of the crystals 8-12 nm.
For the USXES analysis and qualitative estimation of the phases the simulation of experimental findings with the use of the standard SiL2,3 spectra of the amorphous SiC, the crystalline SiC and the amorphous SiH has been made. By the simulation results the conclusion has been made that in the heterostructures Si-C after the pulse photon treatment the heterophase system containing the amorphous and the crystalline phase SiC is formed. Also, the films contain the amorphous phase SiH up to 14%.
The work was performed under the grant of the Russian Foundation for Basic Research No. 06-03-96503r-tsentr-OFI.
|