TY - JOUR
T1 - Novel soft magnetic underlayer for double-layered perpendicular magnetic recording media
T2 - Electroless-deposited films of CoNiFe-based alloy
AU - Asahi, Toru
AU - Yokoshima, Tokihiko
AU - Kawaji, Jun
AU - Osaka, Tetsuya
AU - Ohta, Hiroshi
AU - Ohmori, Masahiro
AU - Sakai, Hiroshi
N1 - Funding Information:
Manuscript received October 15, 2003. This work was carried out at the “Center for Practical Nano-Chemistry” 21C-COE Program, MEXT, Japan. This work was supported in part by grants-in-aid from the Special Coordination Funds for Promoting Science and Technology and by the Center of Excellence Research, MEXT.
PY - 2004/7
Y1 - 2004/7
N2 - We present a novel fabrication process for a soft magnetic underlayer of a CoNiFe-based alloy for a double-layered perpendicular magnetic recording medium using electroless deposition. The electroless-deposited CoNiFeP film is focused on as the soft magnetic underlayer. The CoNiFeP soft magnetic underlayer was fabricated on a 2.5-in glass disk with a Ni/Ti seed layer and the substrate was rotated in an electroless deposition bath under a magnetic field applied. The CoNiFeP underlayer as deposited was flattened using a chemical mechanical polishing, and the film thickness thereby became about 1 μm. The in-plane coercivity and saturation magnetic flux density of the CoNiFeP underlayer were less than 2 Oe and more than 12 kG, respectively. The magnetic domain observation revealed that the CoNiFeP underlayer electroless deposited under the magnetic field applied and the substrate rotated exhibited no marked domain boundary, vanishing a spike noise in read-write experiments. A double-layered perpendicular magnetic recording medium with the electroless-deposited CoNiFeP film showed a sufficient overwrite performance and high signal-to-noise ratio as compared with a typical soft magnetic underlayer fabricated using sputtering.
AB - We present a novel fabrication process for a soft magnetic underlayer of a CoNiFe-based alloy for a double-layered perpendicular magnetic recording medium using electroless deposition. The electroless-deposited CoNiFeP film is focused on as the soft magnetic underlayer. The CoNiFeP soft magnetic underlayer was fabricated on a 2.5-in glass disk with a Ni/Ti seed layer and the substrate was rotated in an electroless deposition bath under a magnetic field applied. The CoNiFeP underlayer as deposited was flattened using a chemical mechanical polishing, and the film thickness thereby became about 1 μm. The in-plane coercivity and saturation magnetic flux density of the CoNiFeP underlayer were less than 2 Oe and more than 12 kG, respectively. The magnetic domain observation revealed that the CoNiFeP underlayer electroless deposited under the magnetic field applied and the substrate rotated exhibited no marked domain boundary, vanishing a spike noise in read-write experiments. A double-layered perpendicular magnetic recording medium with the electroless-deposited CoNiFeP film showed a sufficient overwrite performance and high signal-to-noise ratio as compared with a typical soft magnetic underlayer fabricated using sputtering.
KW - Conife-based alloy
KW - Double-layered perpendicular magnetic recording media
KW - Electroless deposition
KW - Soft magnetic underlayers
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U2 - 10.1109/TMAG.2004.832123
DO - 10.1109/TMAG.2004.832123
M3 - Article
AN - SCOPUS:4444275618
VL - 40
SP - 2356
EP - 2358
JO - IEEE Transactions on Magnetics
JF - IEEE Transactions on Magnetics
SN - 0018-9464
IS - 4 II
ER -