Hitachi Global Storage Technologies Netherlands B.v.

Hitachi, Ltd.

Hgst Netherlands, B.v.

Hitachi Global Storage Technologies Japan, Ltd.

Kabushiki Kaisha Tsuchiya Seisakusho

Takayuki Ichihara

Hiroyuki Nakagawa

Ichiro Tamai

Hiroaki Nemoto

Kyo Akagi

Yoshinori Honda

Ikuko Takekuma

Hisashi Takano

Masafumi Mochizuki

Kiwamu Tanahashi

Yoshiyuki Hirayama

Takehiko Hamaguchi

Mineaki Kodama

Takeji Yogo

Hiroyuki Suzuki

Masayoshi Shimizu

Takuya Matsumoto

Hiroshi Ikeda

Yuzuru Hosoe

Masukazu Igarashi

Yoshiaki Kawato

Hiroyuki Katada

Hideki Zaitsu

Futoshi Tomiyama

Fumio Isshiki

Fumiko Akagi

Hiroyasu Tanabe

Naoto Ito

Ryoko Araki

Akitsuna Nakagaki

Atsuko Kuroda

Eriya Arita

Takeshi Mitomo

Akio Miyazawa

Kosuke Saito

Masuhito Iinuma

Haruo Yokoo

In order to provide a thermal energy assisted medium capable of improving anti-sliding reliability over long periods of time in low flying head conditions, while also maintaining a high SNR, a unique medium is proposed. A soft magnetic layer is formed on a substrate, a soft magnetic layer is formed thereon via a non-magnetic intermediate layer, and an intermediate layer, a crystal oriented control intermediate layer, an artificial lattice intermediate layer having an artificial lattice film in which a first layer comprising Co and a second layer comprising Pt and Pd are laminated repeatedly to form a recording layer, and a cap layer and an lubricating layer are formed. The concentration of Pd comprising the second layer is from about 20 atomic % to about 40 atomic %. Other mediums and systems are also described.

Thermal energy assisted medium

The embodiments of the present invention relate to a shingled magnetic recording system having a magnetic recording medium that has a magnetization easy axis in the recording layer of the medium that is oriented in from the bottom surface to the top surface of the recording layer. Additionally, a magnetization easy axis in the recording layer of the medium is inclined with respect to the recording track width direction.

Magnetic recording with tilted media in the cross track direction

Embodiments of the invention provide a manufacturing method which permits a high quality perpendicular magnetic recording medium to be manufactured with a high yield by preventing abnormal discharge which sputters particles from the target. In one embodiment, while the perpendicular magnetic recording medium is formed, DC pulses are applied to the target. During the reversal period (Reversal Time) between sputtering periods, a voltage of the opposite polarity is applied. During the sputtering period, a negative voltage is applied which biases the target surface to a negative potential, causing Ar+ to collide with and sputter CoCrPt and SiOfor deposition on the intermediate layer. The top surface of the insulation material (SiO) on the target is charged by Ar+ to have a voltage larger than the target voltage. However, arcing can be prevented since the charge on the surface of the insulation material is neutralized due to a positive voltage applied to the target during the non-sputtering period.

Method for manufacturing perpendicular magnetic recording medium

A heat-assisted magnetic recording (HAMR) disk drive has a laser, a transducer coupled to the laser and a rotatable disk. The disk has a recording layer with concentric or spiral data tracks, servo sectors extending across the tracks, a laser power gap adjacent each servo sector, and data sectors between the laser power gaps and the servo sectors. The servo sector preceding the first data sector to be written and the servo sector following the last data sector to be written are identified. Any old data in the data sectors between said first and last servo sectors is acquired, and the old and new data is combined. The laser is turned on when the laser power gap adjacent the first servo sector rotates past the transducer. The combined old and new data is then written in all of the data sectors continuously between said first and last servo sectors.

Heat-assisted magnetic recording (HAMR) disk drive and method for writing

In a magnetic head to be used for a shingled recording method, degradation of a signal resolution and a decrease in a signal-to-noise ratio which are caused by an asymmetrical inter-bit transition curvature are prevented, and a low bit error rate is realized. A magnetic head includes a recording head and a reproducing head. The reproducing head includes a pair of magnetic shields and a sensor sandwiched between the pair of magnetic shields. The gap between the magnetic shields is formed so that the longitudinal direction thereof gets inclined by a certain angle with respect to a cross-track direction in line with the shape of a curvature of an inter-bit transition on an effective record track in a record pattern recorded on a recording medium.

Magnetic head and magnetic disk drive to be used for shingled recording method

A thermally assisted magnetic recording medium includes a substrate and at least two, i.e., first and second magnetic recording layers. These layers are hard magnetic layers and contain magnetic grains and a non-magnetic substance magnetically segregating the magnetic grains at grain boundaries. The first magnetic recording layer has a magnetic anisotropy energy K, a grain volume v, and energy for maintaining its recording magnetization Kv; the second magnetic recording layer has a magnetic anisotropy energy K, a grain volume v, and energy for maintaining its recording magnetization Kv; and the ratio Kv/kT of Kvto a thermal fluctuation energy kT, where krepresents a Boltzmann constant and T represents an absolute temperature, and the ratio Kv/kT of Kvto kT satisfy the following conditions: Kv/kT is larger than Kv/kT at room temperature, but is smaller than Kv/kT at temperatures around the Curie temperature of the first magnetic recording layer.

Thermally assisted recording media and system

Embodiments of the present invention help to provide a discrete track medium for realizing a high track density in a low price by adopting a configuration, in which filling of a non-magnetic material into a guard band portion and smoothing processing of a medium surface are not required. According to one embodiment, a perpendicular magnetic recording medium, on the non-magnetic substrate, includes at least: a soft magnetic underlayer; a first recording layer including a crystal grain having a magnetic property and a non-magnetic grain boundary having an oxide, as a main component, surrounding the crystal grain; a second recording layer containing a ferromagnetic metal as a main component and not containing an oxide; and at least one non-magnetic layer provided between the first recording layer and the second recording layer. A recording track portion for magnetically recording information and a guard band portion provided between adjacent recording track portions are included in the perpendicular magnetic recording medium. The relationship between the total thickness tof the non-magnetic layer in the guard band portion and the total thickness tof the non-magnetic layer in the recording track portion is set as t&#x3e;t

Perpendicular magnetic recording medium, method of manufacturing the same, and magnetic recording device

Embodiments of the present invention provide a perpendicular magnetic recording media having excellent resolution, signal to noise ratio (S/N), and a small adjacent track erasure. According to one embodiment, underlayers for controlling the orientation and segregation of a magnetic layer, a magnetic layer including an oxide and an alloy of magnetic materials mainly composed of Co, Cr, and Pt, and a ferromagnetic-metal layer which does not contain oxygen, are formed over a substrate. The magnetic layer has at least two layers including ferromagnetic grains and oxides, a first magnetic layer, which is the part of the magnetic layer closer to the substrate, has grain boundaries mainly composed of Cr oxide and at least one oxide selected from Si, Ti, Nb, and Ta, and grain boundaries of a second magnetic layer at the ferromagnetic-metal layer side includes at least one oxide selected from Si, Ti, Nb, and Ta in which Cr oxide is less than the first magnetic layer.

Perpendicular magnetic recording media and magnetic storage apparatus using the same

A magnetic recording medium having excellent fly-ability and corrosion resistance is provided in a high yield by controlling protuberant on a medium surface caused by deposition of giant silicon oxide particles, which are created during the film deposition of a granular recording layer including Si and oxygen. In one embodiment of the invention, a recording layer is deposited by a sputtering method using a target which is composed of a mixture of an alloy including at least Co and powdered crystalline SiO.

Manufacturing of magnetic recording medium

A perpendicular magnetic recording medium is manufactured having excellent thermal stability and recording performances across the entire disk surface. In one embodiment, the recording layer includes at least two layers deposited by using a reactive sputtering method under an oxygen-containing atmosphere at a deposition rate larger than the second recording layer which is formed on the first recording layer while depositing the first recording layer on the intermediate layer.

Manufacturing process for perpendicular magnetic recording medium

In a granular magnetic recording layer of a perpendicular magnetic recording medium, media noises are reduced by separating adequately magnetic crystal grains and non-magnetic grain boundary and decreasing magnetic exchange interactions among the magnetic crystal grains without causing damage to magnetic anisotropy of the magnetic crystal grains. In one embodiment, the perpendicular magnetic recording medium, in which crystal alloy grains containing Co, Pt, and Cr, and non-magnetic grain boundary containing Si and O is included; the ratio of the number of O atom to that of Si atom in the magnetic recording layer is between about 2.5 and 5; the Si atomic composition in the magnetic recording layer is between about 3 and 6 atomic %; and the O atomic composition in the magnetic recording layer is between about 12 and 20 atomic %, is used. The in-plane distribution of perpendicular coercivity at any points of the medium of the magnetic recording layer is made at most about &#xb1;10% of an average value.

Perpendicular magnetic recording medium and manufacturing of the same

Disclosed are a perpendicular magnetic recording medium with lower medium noise, insusceptible to thermal fluctuation and high recording resolution and a method of manufacturing it. As the step of forming a metal layer at the time of forming a recording layer on a non-magnetic substrate via a plurality of underlayers and the step of forming an oxide layer with an average thickness of 0.2 nm or less are repeated, the crystal grains are magnetically isolated without disturbing the orientation of the crystal grain of the recording layer of the perpendicular magnetic recording medium or without degrading the magnetic characteristic of the crystal grain of the recording layer.

Perpendicular magnetic recording medium and method of manufacturing it

Embodiments of the invention provide a perpendicular magnetic recording medium capable of reconciling a high recording density with high thermal stability, and having a high write-ability while maintaining high magnetic anisotropy energy. In one embodiment, a perpendicular magnetic recording medium has a soft-magnetic underlayer, and magnetic recording layers, and the magnetic recording layers comprises a first recording layer containing magnetic grains oriented in a direction normal to a medium plane, and a second recording layer containing magnetic grains tilted in a cross-track direction. There can be provided a perpendicular magnetic recording medium resistant to thermal fluctuation, small in medium noise, and excellent in write-ability.

Magnetic recording medium containing first and second recording layers, each layer containing a columnar structure

A hard disk drive and magnetic medium including a servo area, a data area divided into a plurality of sector blocks and at least one micro-servo area disposed between two sector blocks. There may be a micro-servo area immediately preceding each of the plurality of sector blocks. The micro-servo areas include an address mark and a track parity check code that allow the detection of an external shock that causes the recording (write) head to skip to an adjacent track in the hard disk medium. The micro-servo area is smaller than the servo areas, and various numbers of different track parity check codes can be used for different resolution of shock detection. An acceleration sensor may also be provided to detect larger external shocks. By detecting various external shocks with improved accuracy, and aborting the recording operation of data if an external shock is detected, the corruption of data in adjacent tracks is substantially reduced to improve disk drive performance.

Magnetic hard disk drive

Growing community of inventors

Tokyo, Japan

Takayuki Ichihara