Preparation of Fe–Pt perpendicular double-layered media with high electric resistivity backlayer

Magnetic Thin Films for Perpendicular Magnetic Recording Systems

“…Therefore, we should pay attention not only to the recording layer but also the SUL in order to develop high performance perpendicular magnetic recording media. Concerning the SULs, a large value of B s d, where d is the thickness of the SUL, is required for making the most of the writing ability of the magnetic recording head, and various sputter-deposited SULs with the thickness of more than a 100 nm have been reported [8][9][10][11]. However, we face the following critical issues in developing the SULs for practical use.…”

Novel Soft Magnetic Underlayer for Double-Layered Perpendicular Magnetic Recording Media: Electroless-Deposited Films of CoNiFe-Based Alloy

“…Therefore, we need to pay much attention to the development of not only the recording layer but also the SUL in order to fabricate a high-performance perpendicular magnetic recording medium. In particular, the SUL with a high-saturation magnetic flux density is desired to make the best use of writing capability of a recording head, and various sputtered-deposited SULs containing a relatively large amount of Fe element with a thickness of more than a few hundred nanometers have been a focus [1]- [4]. However, we currently face the following critical issues in developing the SULs for a practical use: 1) efficiency of mass productivity is rather low when the thick SUL with a considerable Fe element is sputter deposited and 2) peculiar layered structures are needed to suppress the "spike noise" caused by domain boundaries in the SUL [5]- [7].…”