Epitaxial Co/sub 80/Pt/sub 20/ films with in-plane uniaxial anisotropy

Uniaxial Co
₈₀
Pt
₂₀
epitaxial films with in-plane anisotropy were prepared by dc sputter deposition using W/Ag templates on H-terminated Si(110) substrates. The epitaxial relationship as a function of the CoPt thickness, studied by electron and X-ray diffraction, is complex for CoPt thickness < 5 nm. For CoPt thickness > 5 nm, the epitaxial relationship was found to be CoPt(1010)[0001] || W(112)[110] || Ag(110)[001]|| Si(110)[001]. Anisotropy constants were measured using in-plane torque curves and the initial magnetization curves along the hard axis. For 10 to 20 nm thick Co
₈₀
Pt
₂₀
, Κ1 was found to be ~ 9 × 10
⁶
erg/cc and Κ2 was negligible.