XAFS spectra from reflectivity measurements.

The reflectivity of TiSi(2) films was measured as a function of photon energy E at the Ti K-edge region at a glancing angle theta close to the critical angle theta(C) of total reflection. TiSi(2) silicide films (about 30 nm thickness) were prepared by silicidation of Ti thin films deposited on Si(001) substrates. Since the Fresnel reflectivity R(theta,E) is a function of the dispersion delta(E) and of the absorption beta(E), the absorption beta(E) which carries the XAFS signal can be solved as beta(theta,delta,R) for observed reflectivity R and for estimated delta. The dispersion delta(E) is related to the absorption beta(E) by the Kramers-Kronig (K-K) relations since the refractive index is n(E) = 1 - delta(E) - ibeta(E). beta(E) was calculated from the observed reflectivity R(theta,E) using theoretical values for initial delta(E). Titanium K-edge XAFS for TiSi(2) was extracted from the reflectivity by 'ReflXAFS'.