TY - JOUR
T1 - Columnar Structure in FePt-C Granular Media for Heat-Assisted Magnetic Recording
AU - Varaprasad, B. S.D.C.S.
AU - Wang, J.
AU - Shiroyama, T.
AU - Takahashi, Y. K.
AU - Hono, K.
N1 - Publisher Copyright:
© 1965-2012 IEEE.
PY - 2015/11/1
Y1 - 2015/11/1
N2 - We attempted a compositionally graded sputtering process to overcome the phase separation in the growth direction in the FePt-C granular film in order to realize the columnar structure of FePt grains with an aspect ratio larger than 1.5. In order to overcome the problem of the formation of a second FePt-C layer for the thickness larger than 6 nm, we deposited the FePt-C film by changing the carbon concentration during the sputtering process. The formation of the second FePt-C layer was suppressed, which led to the growth of columnar grains with an aspect ratio of 1.5. The overall volume fraction of carbon is a decisive factor on the size of the FePt grains. Using the compositionally graded process, FePt-C nanogranular films with an average grain size of 7.8 nm, a thickness of 10 nm, and a perpendicular coercivity of 40 kOe were obtained.
AB - We attempted a compositionally graded sputtering process to overcome the phase separation in the growth direction in the FePt-C granular film in order to realize the columnar structure of FePt grains with an aspect ratio larger than 1.5. In order to overcome the problem of the formation of a second FePt-C layer for the thickness larger than 6 nm, we deposited the FePt-C film by changing the carbon concentration during the sputtering process. The formation of the second FePt-C layer was suppressed, which led to the growth of columnar grains with an aspect ratio of 1.5. The overall volume fraction of carbon is a decisive factor on the size of the FePt grains. Using the compositionally graded process, FePt-C nanogranular films with an average grain size of 7.8 nm, a thickness of 10 nm, and a perpendicular coercivity of 40 kOe were obtained.
KW - FePt-C
KW - Heat Assisted Magnetic Recording
KW - columnar structure
KW - granular media
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U2 - 10.1109/TMAG.2015.2435027
DO - 10.1109/TMAG.2015.2435027
M3 - Article
AN - SCOPUS:84946133149
SN - 0018-9464
VL - 51
JO - IEEE Transactions on Magnetics
JF - IEEE Transactions on Magnetics
IS - 11
M1 - 7117424
ER -