Recording Characteristics Of Perpendicular Media Research Articles

Effect of Using Oblique-Incidence Deposited Ru Interlayers Deposited by Evaporation and Sputtering on Recording Characteristics of Perpendicular Media

Oblique-incidence evaporation and sputtering were performed to investigate the effect of reducing the Ru interlayer thickness on the recording characteristics of perpendicular magnetic recording media. Deep gaps were observed at grain boundaries on oblique-incidence evaporated and sputtered films when the incident angle was over 60 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> . Evaporated Ru films have a lower density than sputtered Ru films at the same incident angle. This indicates that the self-shadowing effect predominantly occurs due to suppression of migration of deposited atoms for evaporation films. However, degradation of the crystal orientation is observed in evaporated Ru films due to the present experimental limitations. Examination of the recording characteristics revealed that the Ru interlayer thickness can be reduced by using an oblique-incidence sputtered Ru interlayer and the writing ability can be improved by reducing the spacing loss between the head and the soft magnetic underlayer.

Effects of the exchange stiffness constant and distribution on the recording characteristics of perpendicular media

The relationship between the exchange stiffness constant of a perpendicular medium- and high-density recording characteristics was investigated by micromagnetic simulation. As the exchange stiffness increases, larger magnetic clusters are formed in the ac-erased magnetization state. The shortest recordable bit length of the medium corresponds to the cluster size observed in the ac-erased magnetization state. The slope of the magnetization loop also correlates with the average magnetic cluster size.

垂直磁気記録媒体へのリングヘッド記録におけるヘッドスキュー角の影響

The recording characteristics of perpendicular media with a ring head were investigated experimentally and by simulation to determine their suitability for high-density perpendicular recording. The recording mechanisms of both perpendicular single-layered and double-layered media were clarified by MFM analysis and simulation of the recorded magnetization pattern with a head skew angle. It was found that the effect of the head skew angle on the recording characteristics differs between single-layered and double-layered media.

Recording characteristics of perpendicular media deposited on a ferrite disk substrate

A soft-magnetic ferrite disk substrate was investigated as an underlayer of perpendicular double layer hard disk media for single-pole heads. Although a soft-magnetic thin-film is generally used for the underlayer, concern about the eddy current effect for a metallic underlayer in high-frequency operations. In order to avoid the eddy current, Co–Cr perpendicular media were prepared on the Mn–Zn ferrite substrate to examine their read/write performance. Experimental results with a single-pole writing head and an MR head showed that the ferrite substrate disk had better writing sensitivity and frequency response owing to its large volume and electrical resistivity.

Magnetic Recording Characteristics of Perpendicular Media with a Thin Soft Backlayer Using Merged MR Heads

The recording characteristics of single- and double-layer perpendicular media without and with a thin soft magnetic backlayer were investigated by using merged MR heads. In single-layer media, even a thin soft back-layer with a thickness of 10 nm increased the low-density output and the overwrite property by nearly 4 dB at magnetic spacings of less than 47 nm. In double-layer media with a 10-nm-thick backlayer, no degradation of the recording density was observed.

Track Edge Noise Characteristics in Low Noise Longitudinal and Perpendicular Media

In this paper, we discuss the track-edge noise characteristics in perpendicular media in comparison to longitudinal media. The composition of the magnetic layer was the same in each medium. We found that the track-edge recording characteristics of perpendicular media were very different from those of longitudinal media. Cross-track profiles of normalized medium noise in perpendicular media, considered as a whole, is higher than in longitudinal media. In longitudinal media, distinct track-edge noise was observed, but in perpendicular media, the track-edge noise level is lower than on-track noise. The reason for the low track-edge noise characteristics in perpendicular media is due to a suppressed demagnetize field around the track edge, which results in a sharp track-edge shape. Furthermore, the side-erasure width in perpendicular media is narrower than that in longitudinal media, and is less dependent of the yaw-angle.