Hgst Netherlands, B.v.

Western Digital Technologies, Inc.

Other

John C Read

Jeffrey Childress

Young-Suk Choi

Matthew Joseph Carey

Patrick Braganca

Neil Smith

Yang Li

Shekar B Chandrashekariaih

Neil Leslie Robertson

Kurt A Rubin

Jordan Asher Katine

Michael Grobis

Ricardo Ruiz

Mac D Apodaca

Lei Wan

David Patrick Druist

Goran Mihajlovic

Derek Stewart

Zhaoqiang Bai

William R Wachtler

Tomoya Nakatani

A memory cell includes an ovonic threshold switch (OTS) selector containing a first electrode, a second electrode, an OTS located between the first electrode and the second electrode, and a current focusing layer containing discrete electrically conductive current focusing regions having a width of 30 nm or less located between the first electrode and the OTS, and a memory device located in electrical series with the OTS selector.

Memory device containing selector with current focusing layer and methods of making the same

A phase change memory cell includes a first electrode, a second electrode located over the first electrode, a vertical pillar structure located between the first and second electrodes, the pillar structure containing a first phase change memory (PCM) material portion, a second PCM material portion and an intermediate electrode located between the first PCM material portion and the second PCM material portion, and a resistive liner containing a first segment electrically connected in parallel to the first PCM material portion between the first electrode and the intermediate electrode, and a second segment electrically connected in parallel to the second PCM material portion between the intermediate electrode and the second electrode. The first PCM material portion has a different electrical resistance than the second PCM material portion, and the first segment of the resistive liner has a different electrical resistance than the second segment of the resistive liner.

Multi-level phase change memory cells and method of making the same

Embodiments disclosed herein generally relate to a multilayer magnetic device, and specifically to a spin-torque transfer magnetoresistive random access memory (STT-MRAM) device which provides for a reduction in the amount of current required for switching individual bits. As such, a polarizing reference layer consisting of a synthetic antiferromagnet (SAF) structure with an in-plane magnetized ferromagnet film indirectly exchange coupled to a magnetic film with perpendicular magnetic anisotropy (PMA) is disclosed. By tuning the exchange coupling strength and the PMA, the layers of the SAF may both be canted such that either may be used as a tilted polarizer for either an in-plane free layer or a free layer with PMA.

Tilted synthetic antiferromagnet polarizer/reference layer for STT-MRAM bits

The present disclosure generally relates to a nano-particle matrix in a 3D NVM RRAM device. The RRAM device utilizes a material that may be deposited into high aspect ratio channels, has good cycle ability, short erase and write times, and write/erase voltages that are compatible with CMOS. The RRAM material is disposed between two electrodes of the device and includes conductive nano-particles that are distributed within an insulating matrix. The particles are distributed below the percolation threshold.

Nano-particle matrix for 3D NVM RRAM

Embodiments disclosed herein generally relate to a magnetic head having an amorphous ferromagnetic reference layer. The ferromagnetic reference layer may have amorphous structure as a result of an amorphous ferromagnetic underlayer that the ferromagnetic reference layer is deposited thereon. The amorphous ferromagnetic reference layer enhances magnetoresistance, leading to an improved magnetic head.

Underlayer for reference layer of polycrystalline CPP GMR sensor stack

A disk drive includes a disk including a magnetizable layer of material, and a transducer. The transducer has a read element that includes a first shield layer, a pinned layer, a metallic spacer, an AP (anti-parallel) free layer, and a second shield layer. The pinned layer has a surface area which is greater than the area of the AP free layer. The read element also includes an anti-ferromagnetic layer for substantially fixing the magnetic orientation of a plurality of domains in the pinned layer. The ferromagnetic layer is adjacent the pinned layer. The pinned layer, and the anti-ferromagnetic layer both have surface areas which are greater than the area associated with the AP free layer. The anti-ferromagnetic layer, in one embodiment, has a pinning strength in the range of 0.5 erg/cmto 1.5 erg/cm.

Giant magneto resistive sensor and method for making same

In one embodiment, a device includes a reference layer, a free layer positioned above the reference layer, and a spacer layer positioned between the reference layer and the free layer, the spacer layer providing a gap between the reference layer and the free layer, wherein the reference layer extends beyond a rear extent of the free layer in an element height direction perpendicular to a media-facing surface of the device, and wherein a rear portion of the spacer layer that extends beyond the rear extent of the free layer has an increased resistivity in comparison with a resistivity of a rest of the spacer layer. In other embodiments, a method for forming the device is presented, along with other device structures having an extended pinned layer (EPL).

Magnetic recording head with CPP-GMR spin-valve sensor and extended pinned layer

A magnetic head according to one embodiment includes an underlayer, a first nonmagnetic spacer layer above the underlayer, a free layer above the first nonmagnetic spacer layer, a second nonmagnetic spacer layer above the free layer, and a cap layer above the second nonmagnetic spacer layer. At least one of the cap layer and the underlayer comprises a soft ferromagnetic material and a high spin orbit coupling material. Other embodiments are also described.

Magnetic sensor with doped ferromagnetic cap and/or underlayer

A current-perpendicular-to-the-plane giant magnetoresistance (CPP-GMR) has a multilayer reference layer containing a Heusler alloy. The multilayer reference layer includes a crystalline non-Heusler alloy ferromagnetic layer on an antiferromagnetic layer, a Heusler alloy layer, and an intermediate crystalline non-Heusler alloy of the form CoFeX, where X is one or more of Ge, Al, Si and Ga, located between the non-Heusler alloy layer and the Heusler alloy layer. The CoFeX alloy layer has a composition (CoFe)Xwhere y is between about 10 and 90 atomic percent, and z is between about 50 and 90 atomic percent. The CoFeX alloy layer induces very strong pinning, which greatly lessens the likelihood of magnetic instability by the spin polarized electron flow from the free layer to the reference layer.

Current-perpendicular-to-the-plane (CPP) magnetoresistive sensor with multilayer reference layer including a crystalline CoFeX layer and a Heusler alloy layer

A current-perpendicular-to-the-plane magnetoresistive sensor has an antiparallel free (APF) structure and soft side shields wherein the upper free layer (FL2) of the APF structure is magnetically coupled antiparallel to the top shield and a top shield seed layer via a nonmagnetic antiparallel coupling (APC) layer. In one embodiment the antiparallel coupling is through an antiferromagnetic-coupling (AFC) layer that provides a dominant antiferromagnetic indirect exchange coupling of FL2 to the top shield. In another embodiment the antiparallel coupling is by an APC layer that decouples FL2 and the top shield and causes the edge-induced magnetostatic coupling between FL2 and the seed layer to dominate. The degree of coupling is controlled by the composition and thickness of the nonmagnetic APC layer between FL2 and the seed layer, and by the thickness of the seed layer.

Current-perpendicular-to-the-plane (CPP) magnetoresistive (MR) sensor having an antiparallel free (APF) structure with improved magnetic stability

A method for making a current-perpendicular-to-the-plane (CPP) magnetoresistive (MR) sensor that has a reference layer with low coercivity includes first depositing, within a vacuum chamber, a seed layer and an antiferromagnetic layer on a substrate without the application of heat. The substrate with deposited layers is then heated to between 200-600&#xb0; C. for between 1 to 120 minutes. The substrate with deposited layers is then cooled, preferably to room temperature (i.e., below 50&#xb0; C., but to at least below 100&#xb0; C., in the vacuum chamber. After cooling of the antiferromagnetic layer, the ferromagnetic reference layer is deposited on the antiferromagnetic layer. Then the substrate with deposited layers is removed from the vacuum chamber and subjected to a second annealing, in the presence of a magnetic field, by heating to a temperature between 200-400&#xb0; C. for between 0.5-50 hours.

Method for making a current-perpendicular-to-the-plane (CPP) magnetoresistive sensor having a low-coercivity reference layer

A method and apparatus for increasing the electrical resistivity and corrosion resistance of the material forming a spacer layer in current-perpendicular-to-the-plane (CPP) giant magnetoresistive (GMR) sensors. The increased resistivity of the spacer layer, and thus, the CPP-GMR sensor permits a larger voltage across the sensor and a higher signal-to-noise ratio. The increased corrosion resistance of the spacer layer minimizes the effects of exposing the spacer layer to corrosive materials during fabrication. For example, adding tin to silver to form a metallic alloy spacer layer increases the corrosion resistance of the spacer layer and the electrical resisitivity of the CPP-GMR sensor relative to a spacer layer consisting solely of silver. The Ag&#x2014;Sn alloy permits a larger current to flow through the sensor, which increases the signal-to-noise ratio.

CPP-GMR sensor with corrosion resistent spacer layer and higher signal/noise ratio

An air-bearing slider used in a magnetic recording disk drive has a surface that supports a magnetoresistive (MR) read head or sensor and an electrical lapping guide (ELG) adjacent to the MR sensor. The ELG is formed of a different material than the MR sensor so as to have both a high electrical resistivity and a substantially higher etch rate. When the ELG and MR sensor are etched simultaneously to form their respective back edges, the ELG will have a sharp well-defined non-tapered wall at the back edge. The ELG has a film thickness close to but generally thinner than that of the MR sensor, and a sheet resistance to generally match the resistance measurement capability of the lapping tool. The preferred material for the ELG is an alloy comprising silver (Ag) and one or more of Sn, Ge and zinc Zn.

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San Joes, CA, United States of America

John C Read