ION CHANNELING STUDIES OF EPITAXIAL FE AND CO SILICIDES ON SI

High quality epitaxial Co and Fe silicides have been grown by molecula r beam epitaxy on Si(111) and Si(001) substrates with film thicknesses ranging between 25 and 8400 Angstrom. We used Rutherford backscatteri ng spectrometry channeling techniques to measure the lattice distortio n as a function of film thickness. The critical thickness h(c) corresp onding to the film thickness at which strain relieving dislocations be gin to appear was determined for CoSi2 on Si(111) and Si(001) as well as for Si on CoSi2(111). For CoSi2 on Si(001), a larger critical thick ness was obtained than on Si(111), where h(c) is similar to 45 Angstro m. Epitaxial Si on CoSi2(111) was found to be under a compressive stra in up to thicknesses of about 350 Angstrom depending on substrate miso rientation. Strain measurements were also performed on epitaxially sta bilized Co and Fe monosilicides with the CsCl structure. Channeling me asurements on thick epitaxial films of bcc-Fe, Fe3Si, FeSi, and Fe0.5S i were used to determine the crystalline quality. Excellent channeling minimum yields of 4.0% were found for bcc-Fe/Si(111). The results are compared with structural information obtained from x-ray diffraction and Brillouin scattering spectroscopy. (C) 1994 American Institute of Physics.