Headway Technologies, Incorporated

Magic Technologies, Inc.

Chen-Jung Chien

Chyu-Jiuh Torng

Cherng-Chyi Han

Mao-Min Chen

Min Li

Cheng Tzong Horng

Kunliang Zhang

Ru-Ying Tong

Po-Kang Wang

Moris Musa Dovek

Yun-Fei Li

Kochan Ju

Liubo Hong

Hui-Chuan Wang

Jei-Wei Chang

Yu-Hsia Chen

Wei Cao

Fenglin Liu

Min Zheng

Dan Abels

Ruying Tong

Kowang Liu

Sung Soo Chung

Chyu Jiuh Torng

A magnetic pole suitable for perpendicular magnetic recording is described. This write pole is symmetrically located relative to its side shields and has at least three additional surfaces that are disposed to lie in planes that are normal to the substrate's top surface.

Self-aligned full side shield PMR and method to make it

A hard bias structure for biasing a free layer in a MR element within a read head is comprised of a composite hard bias layer having a CoCrPt/CoCrPtconfiguration. The upper CoCrPtlayer has a larger Hc value and a thickness about 2 to 10 times greater than that of the CoCrPtlayer. The hard bias structure may also include a BCC underlayer such as FeCoMo which enhances the magnetic moment of the hard bias structure. Optionally, the thickness of the CoCrPtlayer is zero and the CoCrPtlayer is formed on the BCC underlayer. The present invention also encompasses a laminated hard bias structure. The Mrt value for the hard bias structure may be optimized by adjusting the thicknesses of the BCC underlayer and CoCrPt layers. As a result, a larger process window is realized and lower asymmetry output during a read operation is achieved.

Hard bias design for extra high density recording

A dynamic fly heater (DFH) for improved lifetime and better film uniformity is disclosed for a magnetic head. The heater has a lower amorphous Ta layer and an upper W layer to promote small grain size and reduced electro-migration. The composite film is especially advantageous for heaters greater than 1000 Angstroms thick where dR/R is difficult to control in the prior art. The DFH may be a (Ta/W)laminate in which the Ta layers are about 30 Angstroms thick and the combined thickness of the W layers is from 400 to 1200 Angstroms. A Ta film is preferably sputter deposited with an Ar pressure of 3 to 5 mTorr and the W film is sputter deposited in the same chamber with a 3 to 20 mTorr Ar pressure. In one embodiment, a merged read/write head has one DFH in the read head and a second DFH in the write head.

Ta/W film as heating device for dynamic fly height adjustment

A method of forming a CPP-GMR spin valve having a pinned layer with an AP2/coupling/AP1 configuration is disclosed wherein the AP2 portion is a FCC-like trilayer having a composition represented by CoFe/FeTa/CoFeor CoFe/FeCo/CoFewhere x is 3 to 30 atomic %, y is 40 to 100 atomic %, and z is 75 to 100 atomic %. Preferably, z is 90 to provide a face centered cubic structure that minimizes electromigration. Optionally, the middle layer is comprised of an Fe rich alloy such as FeCr, FeV, FeW, FeZr, FeNb, FeHf, or FeMo. EM performance is improved significantly compared to a spin valve with a conventional AP2 CoFeor CoFesingle layer. MR ratio is also increased and RA is maintained at an acceptable level. The coupling layer is preferably Ru and the AP1 layer may be comprised of a lamination of CoFe and Cu layers as in [CoFe/Cu]/CoFe.

FCC-like trilayer AP2 structure for CPP GMR EM improvement

A process for forming the write pole of a PMR head is described. This write pole is symmetrically located relative to its side shields, This is accomplished, not through optical alignment, but by coating the pole with a uniform layer of non-magnetic material of a predetermined and precise thickness, followed by the formation of the shield layer around this.

Method for manufacturing a self-aligned full side shield PMR

A laminated main pole layer is disclosed in which a non-AFC scheme is used to break the magnetic coupling between adjacent high moment layers and reduce remanence in a hard axis direction while maintaining a high magnetic moment and achieving low values for Hch, Hce, and Hk. An amorphous material layer with a thickness of 3 to 20 Angstroms and made of an oxide, nitride, or oxynitride of one or more of Hf, Zr, Ta, Al, Mg, Zn, or Si is inserted between adjacent high moment stacks. The laminated structure also includes an alignment layer below each high moment layer within each stack. In one embodiment, a Ru coupling layer is inserted between two high moment layers in each stack to introduce an AFC scheme. An uppermost Ru layer is used as a CMP stop layer. A post annealing process may be employed to further reduce the anisotropy field (Hk).

Laminated film for head applications

A CPP-GMR spin valve having a pinned layer with an AP2/coupling/AP1 configuration is disclosed wherein the AP2 portion is a FCC-like trilayer having a composition represented by CoFe/FeTa/CoFeor CoFe/FeCo/CoFewhere x is 3 to 30 atomic %, y is 40 to 100 atomic %, and z is 75 to 100 atomic %. Preferably, z is 90 to provide a face centered cubic structure that minimizes electromigration. Optionally, the middle layer is comprised of an Fe rich alloy such as FeCr, FeV, FeW, FeZr, FeNb, FeHf, or FeMo. EM performance is improved significantly compared to a spin valve with a conventional AP2 CoFeor CoFesingle layer. The MR ratio of the spin valve is also increased and the RA is maintained at an acceptable level. The coupling layer is preferably Ru and the AP1 layer may be comprised of a lamination of CoFe and Cu layers as in [CoFe/Cu]/CoFe.

A hard bias structure for biasing a free layer in a MR element within a magnetic read head is comprised of a soft magnetic underlayer such as NiFe and a hard bias layer comprised of CoCrPtor CoCrPtthat are rigidly exchange coupled to ensure a well aligned longitudinal biasing direction with minimal dispersions. The hard bias structure is formed on a BCC seed layer such as CrTi to improve lattice matching. The hard bias structure may be laminated in which each of the underlayers and hard bias layers has a thickness that is adjusted to optimize the total H, Mt, and S values. The present invention encompasses CIP and CPP spin values, MTJ devices, and multi-layer sensors. A larger process window for fabricating the hard bias structure is realized and lower asymmetry output and NBLW (normalized base line wandering) reject rates during a read operation are achieved.

Composite hard bias design with a soft magnetic underlayer for sensor applications

A method to fabricate an MTJ device and its connections to a CMOS integrated circuit is described. The device is built out of three layers. The bottom layer serves as a seed layer for the center layer, which is alpha tantalum, while the third, topmost, layer is selected for its smoothness, its compatibility with the inter-layer dielectric materials, and its ability to protect the underlying tantalum.

Bottom conductor for integrated MRAM

In magnetic read heads based on bottom spin valves the preferred structure is for the longitudinal bias layer to be in direct contact with the free layer. Such a structure is very difficult to manufacture. The present invention overcomes this problem by introducing an extra layer between the bias electrodes and the free layer. This layer protects the free layer during processing but is thin enough to not interrupt exchange between the bias electrodes and the free layer. In one embodiment this is a layer of copper about 5 &#x212b; thick and parallel exchange is operative. In other embodiments ruthenium is used to provide antiparallel exchange between the bias electrode and the free layer. A process for manufacturing the structure is also described.

Patterned exchange bias GMR using metallic buffer layer

A structure that is well suited to connecting an MTJ device to a CMOS integrated circuit is described. It is built out of three layers. The bottom layer serves as a seed layer for the center layer, which is alpha tantalum, while the third, topmost, layer is selected for its smoothness, its compatibility with the inter-layer dielectric materials, and its ability to protect the underlying tantalum. A method for its formation is also described.

A spin-valve magnetoresistive read element has a thin conductive lead layer of high sheet conductivity, high hardness, high melting point, high corrosion resistance and lacking the propensity for smearing, oozing, electromigration and nodule formation. Said lead layer is formed upon the hard magnetic longitudinal bias layer of an abutted junction spin-valve type magnetoresistive read head and said read head is therefore suitable for reading high density recorded disks at high RPM.

Robust hard bias/conductor lead structures for future GMR heads

A method for fabricating a longitudinally hard biased, bottom spin valve GMR sensor with a lead overlay (LOL) conducting lead configuration and a narrow effective trackwidth. The advantageous properties of the sensor are obtained by providing two novel barrier layers, one of which prevents oxidation of and Au diffusion into the free layer during annealing and etching and the other of which prevents oxidation of the capping layer during annealing so as to allow good electrical contact between the lead and the sensor stack.

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Sunnyvale, CA, United States of America

Chen-Jung Chien