STRUCTURAL INVESTIGATION OF FE SILICIDE FILMS GROWN BY PULSED-LASER DEPOSITION

Pulsed laser deposition was used to grow epitaxial beta-FeSi, films on Si(111) (1X1) and Si(111) (7X7) with the following epitaxial orientat ions: beta-FeSi2(001)//Si(111) with beta-FeSi2[010]//Si[110] and three rotational variants. Silicide growth was influenced by substrate temp erature and deposition rate, but not by the structure of the starting surface. Films containing both beta-FeSi, and FeSi were formed at low substrate temperatures and high deposition rates, while films containi ng only beta-FeSi2 were formed at higher substrate temperatures and lo wer deposition rates. FeSi grains had the following epitaxial relation ship to the Si substrate, FeSi(111)//Si(111) with FeSi(110BAR)//Si(112 BAR). The microstructure of the silicide films varied with film thickn ess, as did the roughness at the silicide/Si interface. These results suggest that an Fe-rich environment was created during the growth of t he silicide films.