Epitaxial Ag templates on Si(001) for bicrystal CoCrTa media

Ag thin films were sputter deposited on hydrofluoric acid-etched Si(001) single crystal substrates and employed as templates for the epitaxial growth of Cr(001) films and consequently bicrystal CoCrTa(<11(2)over bar 0>) films. The orientation relationship was determined to be bicrystal CoCrTa on Cr(001)[100]parallel to Ag(001)[110]parallel to Si(001)[110]. X-ray diffraction analysis showed only strong Ag(002) peaks throughout the Ag film thickness range of 50-1500 Angstrom. Atomic force microscopy showed that almost continuous Ag films can be achieved in the thickness range of 500-1000 Angstrom, which result in the highest coercivities in CoCrTa films whose magnetic properties were found to vary with the Ag template thickness and surface morphology. The periodic in-plane angular variation of magnetic properties and torque curves with a four-fold symmetry were confirmed in the bicrystal CoCrTa films. (C) 1997 American Institute of Physics.