Headway Technologies, Incorporated

Kabushiki Kaisha Toshiba

Tdk Corporation

Magic Technologies, Inc.

Kunliang Zhang

Min Li

Hui-Chuan Wang

Tong Zhao

Yuchen Zhou

Yu-Hsia Chen

Chyu-Jiuh Torng

Yewhee Chye

Junjie Quan

Kenichi Takano

Yue Liu

Glen A Garfunkel

Moris Musa Dovek

Wenyu Chen

Chen-Jung Chien

Hideaki Fukuzawa

Hiromi Yuasa

Simon H Liao

Min Zheng

Ruhang Ding

Kochan Ju

Joe Smyth

Yu-Chen Zhou

Yoshihiko Fuji

Michiko Hara

Yan Wu

Kowang Liu

Shohei Kawasaki

Shengyuan Wang

Cheng Tzong Horng

Erhard Theodor Schreck

Cherng-Chyi Han

Yun-Fei Li

Hui Wang

Liejie Guan

Ru-Ying Tong

Zhigang Bai

Po-Kang Wang

Shuichi Murakami

Mao-Min Chen

Katsuhiko Koui

Kenichiro Yamada

Masanori Sakai

Soichi Oikawa

Tom Zhong

Youfeng Zheng

Yoshinari Kurosaki

Yunfei Li

Jianing Zhou

Masashi Sano

Koichi Terunuma

PoKang Wang

Dan Abels

Rachid Sbiaa

Hiroshi Omine

Hitoshi Iwasaki

Zheng Gao

Masayuki Takagishi

Lijie Guan

Akihiko Takeo

Tomomi Funayama

Xuhui Jin

Masahiro Takashita

Weihao Xu

Fenglin Liu

Sangmun Oh

Chyu Jiuh Torng

Xiaomin Liu

Daniel Gerard Abels

Zhi Gang Bai

Hui-Chaun Wang

Yu-Hsai Chen

The present embodiments relate to a tunnel magnetoresistance (TMR) element. The TMR element can include a free layer comprising a metallic alloy that is doped using a dopant element. In some instances, the metallic alloy comprises a cobalt-iron (CoFe) alloy. The present embodiments relate to doping a small amount of an element (e.g., hafnium (Hf), tantalum (Ta), Yttrium (Y)) in a high flux CoFe layer of a tunnel magnetoresistance (TMR) element. The small amount of dopant can suppress a long-range order in the CoFe film. The amorphous state of a CoFe alloy can be induced by the dopant and result in a magnetically soft layer. A resistance of the TMR element can be modified based on an application of an external magnetic field to the free layer and the pin layer.

Tunneling magnetoresistance device with magnetically soft high moment free layer

Systems and methods for controlling a critical dimension (CD) uniformity of a magnetic head device are described. A film stack that is part of a system for controlling a critical dimension (CD) uniformity of a magnetic head device can include a substrate, a magnetoresistive (MR) sensor layer, and a hard mask layer. The system can also include a first mask that defines critical shape patterns other than the CD. The hard mask layer can be patterned using the first mask. The system can also include a second mask that defines the CD. A mandrel pattern can be formed on the hard mask layer using the second mask.

System for controlling a critical dimension (CD) uniformity of a magnetic head device

A read head includes a permanent magnet (PM) layer formed up to 100 nm behind a free layer where PM layer magnetization may be initialized in a direction that adjusts free layer (FL) bias point, and shifts sensor asymmetry (Asym) closer to 0% for individual heads at slider or Head Gimbal Assembly level to provide a significant improvement in device yield. Asym is adjusted using different initialization schemes and initialization directions. With individual heads, initialization direction is selected based on a prior measurement of asymmetry. The PM layer is CoPt or CoCrPt and has coercivity from 500 Oersted to 1000 Oersted. The PM layer may have a width equal to the FL, or in another embodiment, the PM layer adjoins a backside of the top shield and has a width equal to or greater than that of the FL.

Adaptive bias control for magnetic recording head

Methods of critical dimension (CD) uniformity control for magnetic head devices are disclosed. In some embodiments, a method can include providing a film stack, the film stack including a substrate, a magnetoresistive (MR) sensor layer, and a hard mask layer, patterning the hard mask layer using a first mask that defines critical shape patterns other than the CD, forming a mandrel pattern using a second mask that defines the CD, and forming a sidewall spacer pattern on sidewalls of the mandrel pattern, and removing the mandrel pattern.

Method of ultra-fine critical dimension patterning for magnetic head devices

A read head includes a permanent magnet (PM) layer formed up to 100 nm behind a free layer where PM layer magnetization may be initialized in a direction that adjusts free layer (FL) bias point, and shifts sensor asymmetry (Asym) closer to 0% for individual heads at slider or Head Gimbal Assembly level to provide a significant improvement in device yield. Asym is adjusted using different initialization schemes and initialization directions. With individual heads, initialization direction is selected based on a prior measurement of asymmetry. The PM layer is CoPt or CoCrPt and has coercivity from 500 Oersted to 1000 Oersted. The PM layer may have a width equal to the FL, or a width equal to the cross-track distance between outer sides of the longitudinal bias layers. In another embodiment, the PM layer adjoins a backside of the top shield.

A hard magnet stabilization scheme is disclosed for a top shield and junction shields for double or triple dimension magnetic reader structures. In one design, the hard magnet (HM) adjoins a top or bottom surface of all or part of a shield domain such that the HM is recessed from the air bearing surface to satisfy reader-to-reader spacing requirements and stabilizes a closed loop magnetization in the top shield. The HM may have a height and width greater than that of the top shield. The top shield may have a ring shape with a HM formed above, below, or within the ring shape, and wherein the HM stabilizes a vortex magnetization. HM magnetization is set or reset from room temperature to 100&#xb0; C. to maintain a desired magnetization direction in the top shield, junction shield, and free layer in the sensor.

Hard magnetic stabilized shield for double (2DMR) or triple (3DMR) dimension magnetic reader structures

The use of supermalloy-like materials such as NiFeMe where Me is one or more of Mo, Cr, and Cu for the side and top shields of a magnetic bit sensor is shown to provide better shielding protection from stray fields because of their extremely high permeability. Moreover, the side shield may comprise a stack in which a Ni, Fe, Co, FeNi, CoFe, or FeCo is sandwiched between two NiFeMe layers to enhance the bias field on an adjacent free layer. Including NiFeMe in a side shield results in an increase in readback amplitude under the same asymmetric sigma. For these sensors, the signal to noise ratio was higher and the bit error rate was lower than with conventional materials in the side shield. A method is disclosed for forming a magnetic bit sensor having supermalloy-like materials in the side shields.

Supermalloy and MU metal side and top shields for magnetic read heads

Hard magnet stabilized shield for double (2DMR) or triple (3DMR) dimension magnetic reader structures

A PMR (perpendicular magnetic recording) head is configured for thermally assisted magnetic recording (TAMR). The thermal energy is supplied by the near-fields of plasmons and the near-fields are directed to a magnetic recording medium by a PPG layer. The PPG layer is Rhodium (Rh) whose small-grained crystal structure normally makes it subject to thermal deformations and other weaknesses. By growing the PPG layer on a thin template layer (TTL), the portion of the PPG layer adjacent to the air-bearing surface (ABS) develops a larger grain size and stronger forces between its atomic constituents which makes it resistant to those deformations.

Rhodium film with thin template layer and its application to a thermally assisted magnetic recording (TAMR) writer

A seed layer stack with a smooth top surface having a peak to peak film thickness variation of about 0.5 nm is formed by sputter depositing a second seed layer on a first seed layer that is Mg, MgN, or an alloy thereof where the second seed layer has a bond energy substantially greater than that of the first seed layer. The second seed layer may be Ta or NiCr. In some embodiments, an uppermost seed layer that is one or both of Ru and Cu is deposited on the second seed layer. Higher coercivity (Hc) and perpendicular magnetic anisotropy (Hk) is observed in an overlying ferromagnetic layer than when a prior art seed layer stack is employed. The first seed layer has a thickness from 2 to 20 Angstroms and has a resputtering rate about 2 to 40 times that of the second seed layer.

Composite seed layer

A process flow is disclosed for forming a MR sensor having an antiferromagnetic (AFM) layer recessed behind a bottom shield to reduce reader shield spacing and improve pin related noise. An AP/AFM coupling layer/APstack that extends from an air bearing surface to the MR sensor backside is formed above the AFM layer. The APlayer is pinned by the AFM layer, and the APlayer serves as a reference layer to an overlying free layer during a read operation. The APand APlayers have improved resistance to magnetization flipping because back portions thereof have a full cross-track width 'w' between MR sensor sides thereby enabling greater pinning strength from the AFM layer. Front portions of the AP/APlayers lie under the free layer and have a track width less than 'w'. The bottom shield may have an anti-ferromagnetic coupling structure.

Magnetic reader sensor with shield spacing improvement and better pin flip robustness

A hard magnet stabilization scheme is disclosed for a top shield and junction shields for double or triple dimension magnetic reader structures. In one design, the hard magnet (HM) adjoins a top or bottom surface of all or part of a shield domain such that the HM is recessed from the air bearing surface to satisfy reader-to-reader spacing requirements and stabilizes a closed loop magnetization in the top shield. Alternatively, the HM may replace a shield domain. The top shield may have various shapes including a ring shape in which the HM stabilizes a vortex magnetization. In a whole shield coupling design, the HM contacts all of the top shield bottom surface except over the sensor and junction shield. HM magnetization is set or reset from room temperature to 100&#xb0; C. to maintain a desired magnetization direction in the top shield, junction shield, and free layer in the sensor.

A method of forming a sub-structure, suitable for use as a hot seed in a perpendicular magnetic recording head, is described. A buffer layer of alumina with a thickness of 50-350 Angstroms is formed by atomic layer deposition as a write gap. Thereafter, one or more seed layers having a body-centered cubic (bcc) crystal structure may be deposited on the buffer layer. Finally, a magnetic film made of FeCo or FeNi with a coercivity of 60-110 Oe is deposited on the seed layer(s) by a physical vapor deposition (PVD) method at a rate of 0.48 to 3.6 Angstroms per second. The magnetic film is preferably annealed at 220&#xb0; C. for 2 hours in a 250 Oe applied magnetic field.

Method of manufacturing a magnetic film having high coercivity for use as a hot seed in a magnetic write head

A MR sensor is disclosed with an antiferromagnetic (AFM) layer recessed behind a bottom shield to reduce reader shield spacing and improve pin related noise. Above the AFM layer is an AP2/AFM coupling layer/AP1 stack that extends from an air bearing surface to the MR sensor backside. The AP2 layer is pinned by the AFM layer, and the AP1 layer serves as a reference layer to an overlying free layer during a read operation. The AP1 and AP2 layers have improved resistance to magnetization flipping because back portions thereof have a full cross-track width 'w' between MR sensor sides thereby enabling greater pinning strength from the AFM layer. Front portions of the AP1/AP2 layers lie under the free layer and have a track width less than 'w'. The bottom shield may have an anti-ferromagnetic coupling structure. A process flow is provided for fabricating the MR sensor.

Magnetic reader sensor with shield spacing improvement and better pin flop robustness

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Fremont, CA, United States of America

Kunliang Zhang