Li MA（马丽）, Cong-mian ZHEN（甄聪棉）, Zhao-guang PANG（庞兆广）, Deng-lu HOU（侯登录）
(Hebei Advanced Thin Films Laboratory, College of Physics Science and Information Engineering, Hebei Normal University, Shijiazhuang 050016, China)
Abstract-Co5Sm/Cr bilayer films were deposited on Si and glass slides by means of a Direct-Current (DC) magnetron sputtering system with substrate heating. Magnetic properties measurements show that the sample with glass substrate has a comparatively large coercivity (Hc=2 141.2 Oe) with a relatively low optimal temperature (Ts=350 ℃). X-ray diffraction patterns indicate that Cr presents a hexagonal-close-packed (hcp) texture on Si, while a body-centered-cubic (bcc) structure on glass substrate, which leads to Co5Sm films having different lattice constants on Si and glass substrates. At their optimal temperature, the grain size of the sample on glass slide is smaller with its size distribution more uniform. Concurrently, the shape of magnetic domain is more regular and ordered. The value of magnetic switching volume (V*) for the film on glass is 1.65×10-18 cm3, smaller than that for films on Si. For the film on glass, the magnetization reversal mechanism is mainly influenced by magnetocrystalline anisotropy, the shape of the crystal grain and the stress in the film.
Key words-magnetic recording media; magnetron sputtering; Co5Sm; substrate
Manuscript Number: 1674-8042(2011)04-0317-04
doi: 10.3969/j.issn.1674-8042.2011.04.003
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