Unicrystal Co–alloy media on Si(110)

Unicrystal Co–alloy/Cr/Ag films, which exhibit a single, in-plane easy axis orientation, were epitaxially grown on hydrofluoric acid etched Si(110) single crystal substrates by sputter deposition for the purpose of the systematic study of Co–alloy magnetocrystalline anisotropy. The orientation relationship was studied by x-ray θ/2θ diffraction, pole figure φ scan, and transmission electron microscopy, and it was determined to be Co(101̄0)[0001]‖Cr(112)[11̄0]‖Ag(110)[001]‖Si(110)[001]. The φ scan also showed two twin-related orientations of Cr grains. The easy axis hysteresis loops had a square shape, while the hard axis loops showed zero openness. The uniaxial anisotropy constants K1 and K2 of the unicrystal Co and CoCrTa films were determined from torque and hard axis hysteresis loop measurements.