Title :
Grain Size Reduction by Doping Cr Underlayer with Ru for Longitudinal Magnetic Recording Media
Author :
Sun, An-Cheng ; Hsu, Jen-Hwa ; Sheng, C.H. ; Kuo, P.C. ; Huang, H.L.
Author_Institution :
Dept. of Phys. & Center for Nanostorage Res., Nat. Taiwan Univ., Taipei
Abstract :
A Cr underlayer was doped with 10 at. % Ru to enlarge the Cr lattice and promote the Co(11.0) formation of the CoCrPtTaB magnetic layer by in-plane tensile stress at a recording layer/underlayer interface. The texture, grain size and magnetic characteristics of CoCrPtTaB/Cr(Ru) were examined as well. The CrRu(002) underlayer exhibit markedly enhanced Co(11.0) orientation, increasing coercivity and preferential alignment of the c-axis. The grain size and grain size distribution of the recording layer decreased as the CoCrPtTaB magnetic layer grew epitaxially on the CrRu underlayer. The grain size of the recording layer was reduced from 11.2 nm with a pure Cr underlayer to 5.4 nm with a CrRu underlayer. The latter is the smallest grain size yet reported for CoCr-based alloy recording media
Keywords :
boron alloys; chromium alloys; cobalt alloys; coercive force; grain size; interface magnetism; magnetic epitaxial layers; magnetic recording; metallic thin films; platinum alloys; ruthenium alloys; tantalum alloys; texture; CoCrPtTaB-CrRu; coercivity; doping; grain size; grain size distribution; grain size reduction; in-plane tensile stress; longitudinal magnetic recording media; magnetic layer; magnetic properties; preferential alignment; recording layer-underlayer interface; texture; underlayer; Chromium; Crystallography; Doping; Grain size; Lattices; Magnetic recording; Signal to noise ratio; Sputtering; Sun; Tensile stress; Chromium alloys; cobalt alloys; epitaxial growth; magnetic recording;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2006.888490
