T. Asahi et al., Influence of substrates on magnetic property and crystalline orientation of CoCrTa/TiCr perpendicular magnetic recording medium, J MAGN MAGN, 212(1-2), 2000, pp. 293-299
The influence of substrates on magnetic property and crystalline orientatio
n of CoCrTa/TiCr perpendicular magnetic recording medium was investigated u
sing a glass plate and a Si(1 0 0) single crystal. Magnetic measurements re
vealed that the film sputtered on a Si(1 0 0) substrate possessed a higher
perpendicular coercive force than that on glass, where the pretreatment of
the Si(1 0 0) substrate by aqueous HF solution effectively improved the mag
netic properties. X-ray diffraction analysis of the films indicated that th
e crystallinity of the TiCr layer formed on the Si(1 0 0) substrate with th
e HF pretreatment was higher than that on the glass substrate. It was also
found that CoCrTa and TiCr layers on the Si(1 0 0) substrate with the KF pr
etreatment had a narrower distribution of their c-axis orientation than tho
se on glass substrate. The results of X-ray diffraction analysis were consi
stent with those of the TEM observation for cross-section bright- and dark-
field images and the corresponding THEED patterns. These results suggest th
at the crystalline surface of the Si(1 0 0) substrate with HF pretreatment
has the effect of inducing preferred orientation in the TiCr underlayer, wh
ich leads to a decrease in distribution of the c-axis orientation of Co gra
ins in the CoCrTa layer, resulting in an increase in the perpendicular coer
cive force. (C) 2000 Elsevier Science B.V. All rights reserved.