Western Digital (fremont), Inc.

Wd Media, LLC

Western Digital Technologies, Inc.

Komag Corporation

Sandisk Technologies Inc.

Gerardo Bertero

Shaoping Li

Ming Mao

Qunwen Leng

Michael L Mallary

Shihai He

Yuankai Zheng

David Treves

Steven C Rudy

David E Wachenschwanz

Sudhir S Malhotra

Alan Kalitsov

Rongfu Xiao

Ge Yi

Derek Stewart

Donald C Stafford

Andrew M Homola

Tu Chen

Christopher H Bajorek

Donald Joseph Brunnett

Michael Alex

Zhihong Zhang

James L Chao

Neil Leslie Robertson

Michael Grobis

Yunfei Ding

B Ramamurthy Acharya

Mac D Apodaca

Anup Roy

Michael Nicolas Albert Tran

Eric J Champion

Zhaoqiang Bai

Charles Changqing Chen

Yingbo Zhang

Hong-Sik Jung

Haiwen Xi

Zhitao Diao

Daniel Bedau

Antony Ajan

Tsutomu Tom Yamashita

Christopher L Beaudry

Christopher B Wolf

Tomoko Seki

Ling Wang

Michinobu Suekane

Makoto Imakawa

Miaoyin Wang

Daniel K Lottis

Zhengsheng Shan

Chen Jung Chien

Ananth Kaushik

Abhinandan Chougule

Emur M Velu

Kuok San Ho

Lei Wang

Feng Q Liu

Paul Christopher Dorsey

Lien-Chang Wang

Chen-jung Chien

Guanxiong Li

Hua Yuan

Donghong Li

Alexander S Chernyshov

Kumar Srinivasan

Zhipeng Li

Hoan Cong Ho

Diep Nguyen

Wei Cao

Changhe Shang

Haifeng Wang

Bincheng Wang

Fenghua Zong

Ching Jackie Tsoi

Jianxin Fang

Javier Wong

Debashish Tripathy

Guolun Hao

Oleg Mryasov

Srikanth Ganesan

Ruisheng Liu

Mazin Almaqablah

Jackie Tsoi Jung

A magnetoresistive memory cell includes a magnetoresistive layer stack containing a reference layer, a nonmagnetic spacer layer, and a free layer. A ferroelectric material layer having two stable ferroelectric states is coupled to a strain-modulated ferromagnetic layer to alter a sign of magnetic exchange coupling between the strain-modulated ferromagnetic layer and the free layer. The strain-modulated ferromagnetic layer may be the reference layer or a perpendicular magnetic anisotropy layer that is located proximate to the ferroelectric material layer. The magnetoresistive memory cell may be configured as a three-terminal device or as a two-terminal device, and may be configured as a tunneling magnetoresistance (TMR) device or as a giant magnetoresistance (GMR) device.

Magnetoresistive memory device and method of operating same using ferroelectric-controlled exchange coupling

A ferroelectric memory device contains a two-dimensional semiconductor material layer having a band gap of at least 1.1 eV and at least one of a thickness of 1 to 5 monolayers of atoms of the semiconductor material or includes a two-dimensional charge carrier gas layer, a source contact contacting a first portion of the two-dimensional semiconductor material layer, a drain contact contacting a second portion of the two-dimensional semiconductor material layer, a ferroelectric memory element located between the source and drain contacts and adjacent to a first surface of the two-dimensional semiconductor material layer, and a conductive gate electrode located adjacent to the ferroelectric memory element.

Ferroelectric memory devices employing conductivity modulation of a thin semiconductor material or a two-dimensional charge carrier gas and methods of operating the same

A two-step SET pulse may be applied to a phase change material of a phase change memory cell in which a first lower SET pulse is applied to make the phase change material dwell at 600K to incubate nuclei near the maximum nucleation rate and then a second higher SET pulse is immediately applied to make the phase change material dwell at 720K to maximize crystal growth. Moreover, the slope of the falling edge of a RESET pulse applied prior to the two-step SET pulse may be adjusted to increase the number of nuclei (e.g., formed with a steeper falling edge) to increase SET efficiency at the expense of a more stable amorphous phase (e.g., formed with a less steep falling edge) that improves data retention.

Set/reset methods for crystallization improvement in phase change memories

A phase change memory device includes a phase change material portion located between a first electrode and a second electrode, and a crystallization template material portion located between the first electrode and the second electrode in contact with the phase change material portion. The crystallization template material portion and the phase change material portion belong to a same crystal system and have matching lattice spacing, or the crystallization template material portion and the phase change material portion do not belong to the same crystal system, but have a matching translational symmetry along at least one paired lattice plane with a matching lattice spacing.

Phase change memory device with crystallization template and method of making the same

Systems and methods for improving the crystallization of a phase change material of a phase change memory cell are described. A two-step SET pulse may be applied to the phase change material in which a first lower SET pulse is applied to make the phase change material dwell at 600K to incubate nuclei near the maximum nucleation rate and then a second higher SET pulse is immediately applied to make the phase change material dwell at 720K to maximize crystal growth. Moreover, the slope of the falling edge of a RESET pulse applied prior to the two-step SET pulse may be adjusted to increase the number of nuclei (e.g., formed with a steeper falling edge) to increase SET efficiency at the expense of a more stable amorphous phase (e.g., formed with a less steep falling edge) that improves data retention.

A magnetoresistive memory device includes a magnetic-exchange-coupled layer stack containing a free layer, a reference layer and an electrically conductive, non-magnetic interlayer exchange coupling layer located between the free layer and the reference layer, and an insulating spacer layer located in a series connection with the magnetic-exchange-coupled layer stack between a first electrode and a second electrode. The first electrode and the second electrode are configured to provide a programming voltage across the magnetic-exchange-coupled layer stack and the insulating spacer layer.

Voltage-controlled interlayer exchange coupling magnetoresistive memory device and method of operating thereof

A magnetic read apparatus includes a read sensor, a shield structure and a side magnetic bias structure. The read sensor includes a free layer having a side and a nonmagnetic spacer layer. The shield structure includes a shield pinning structure and a shield reference structure. The nonmagnetic spacer layer is between the shield reference structure and the free layer. The shield reference structure is between the shield pinning structure and the nonmagnetic spacer layer. The shield pinning structure includes a pinned magnetic moment in a first direction. The shield reference structure includes a shield reference structure magnetic moment weakly coupled with the pinned magnetic moment. The side magnetic bias structure is adjacent to the side of the free layer.

Free layer magnetic reader that may have a reduced shield-to-shield spacing

A heat assisted magnetic recording (HAMR) media structure is disclosed. The HAMR media structure includes a magnetic recording layer comprising an array of magnetic grains for storing information; a heat sink layer disposed below the magnetic recording layer and having a first thermal conductivity; and an anisotropic thermal barrier layer disposed between the magnetic recording layer and the heat sink layer and having a vertical thermal conductivity and an in-plane thermal conductivity, wherein the vertical thermal conductivity is substantially higher than the in-plane thermal conductivity.

HAMR media structure having an anisotropic thermal barrier layer

A magnetic read apparatus includes a media-facing surface (MFS), a sensor, a shield structure, a side bias structure, and a shield reference bias structure. The sensor includes a free layer and a nonmagnetic layer. The shield structure includes a shield pinning structure and a shield reference structure between the shield pinning structure and the nonmagnetic layer. The nonmagnetic layer is between the free layer and a shield reference structure. The shield pinning structure includes a pinned moment oriented in a first direction. The shield reference structure includes a reference structure moment weakly coupled with the pinned moment. The side bias structure is adjacent to a side of the free layer and biases the free layer in a first direction parallel to the MFS. The shield reference bias structure is adjacent to the shield reference structure and biases the shield reference structure in a direction opposite to the first direction.

Free layer only magnetic reader that may have a reduced shield-to-shield spacing and a multilayer side bias

A recording medium having improved signal-to-noise ratio (SNR) capabilities includes dual cap layers over the recording layer, where the Curie temperature of the first cap layer over the recording layer is greater than the Curie temperature of the recording layer, and the Curie temperature of the second cap layer over the first cap layer is greater than the Curie temperature of the first cap layer. The first cap layer may be composed of a magnetically hard material, such as L1CoPt, where the second cap layer may be composed of a magnetically soft material, such as Co. Such a medium is particularly useful in the context of heat-assisted magnetic recording (HAMR).

Dual cap layers for heat-assisted magnetic recording media

A tunnel magnetoresistance (TMR) read sensor having a tabbed AFM layer and an extended pinned layer and methods for making the same are provided. The TMR read sensor has an AFM layer recessed from the air bearing surface, providing a reduced shield-to-shield distance.

Magnetic read head with antiferromagentic layer

A soft underlayer (SUL) and methods for making an SUL are provided, the SUL having characteristics that make it compatible with the high temperature requirements associated with heat-assisted magnetic recording (HAMR) media growth and writing, e.g., temperatures greater than 500&#xb0; C. The SUL may have a high crystallization temperature of greater than 450&#xb0; C. and a high Curie temperature greater than 300&#xb0; C., for example. Additionally, the SUL can maintain a saturation magnetization value greater than, e.g., 9 kGauss, at such high temperatures, thereby having the ability to remain amorphous at temperatures up to, e.g., 650&#xb0; C., and exhibiting a relatively flat integrated noise profile from approximately 300&#xb0; C. to 650&#xb0; C. Further still, a spacer layer material is chosen such that inter-diffusion does not occur at these high temperatures.

Soft underlayer for heat assisted magnetic recording media

Apparatuses and methods for providing thin shields in a multiple sensor array are provided. One such apparatus is a magnetic read transducer including a first read sensor, a second read sensor, and a shield assembly positioned between the first read sensor and the second read sensor at an air bearing surface (ABS) of the magnetic read transducer, the shield assembly including a first shield layer assembly having a first footprint with a first area, and a second shield layer assembly having a second footprint with a second area, where the second area is greater than the first area.

Apparatuses and methods for providing thin shields in a multiple sensor array

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Redwood City, CA, United States of America

Gerardo Bertero