Western Digital Technologies, Inc.

Sandisk Technologies Inc.

California State University, Northridge

Alan Kalitsov

Bhagwati Prasad

Derek Stewart

Gerardo Bertero

Matthew Joseph Carey

Bruce David Terris

Neil Smith

Daniel Bedau

Ananth Kaushik

Masaaki Higashitani

Peter Rabkin

Paul Christopher Dorsey

Lei Wan

Goran Mihajlovic

Kumar Srinivasan

Hoan Cong Ho

Tiffany Santos

Nicholas Kioussis

Julian Velev

Artur Useinov

Rajesh Chopdekar

Oleg Mryasov

A memory device includes a first electrode, a second electrode, and a magnetic tunnel junction located between the first electrode and the second electrode. The magnetic tunnel junction includes a reference layer, a free layer, a nonmagnetic tunnel barrier layer located between the reference layer and the free layer, and a platinum-containing layer containing platinum and at least one element selected from iridium, hafnium or ruthenium. The platinum-containing layer contacts the free layer.

Voltage controlled magnetic anisotropy (VCMA) memory devices including platinum containing layer in contact with free layer

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 magnetoelectric memory device includes a magnetic tunnel junction located between a first electrode and a second electrode. The magnetic tunnel junction includes a reference layer, a nonmagnetic tunnel barrier layer, a free layer, and a dielectric capping layer. At least one layer that provides voltage-controlled magnetic anisotropy is provided within the magnetic tunnel junction, which may include a pair of nonmagnetic metal dust layers located on, or within, the free layer, or a two-dimensional metal compound layer including a compound of a nonmagnetic metallic element and a nonmetallic element.

Voltage-controlled magnetic anisotropy memory device including an anisotropy-enhancing dust layer and methods for forming the same

Magnetoelectric or magnetoresistive memory cells may include a plurality of reference layers and optionally a plurality of free layers to enhance the tunneling magnetoresistance (TMR) ratio.

Magnetoresistive memory device including a plurality of reference layers

A magnetoresistive memory device includes a magnetic tunnel junction including a free layer, at least two tunneling dielectric barrier layers, and at least one metallic quantum well layer. The quantum well layer leads to the resonant electron tunneling through the magnetic tunnel junction in such a way that it strongly enhances the tunneling probability for one of the magnetization states of the free layer, while this tunneling probability remains much smaller in the opposite magnetization state of the free layer. The device can be configured in a spin transfer torque device configuration, a voltage-controlled magnetic anisotropy, a voltage controlled exchange coupling device configuration, or a spin-orbit-torque device configuration.

Magnetic tunnel junction memory devices employing resonant tunneling and methods of manufacturing the same

A magnetic memory device includes a first electrode, a second electrode, and a layer stack located between the first electrode and the second electrode. The layer stack includes a reference layer, a tunnel barrier layer, a free layer, and a magnetoelectric multiferroic layer including at least one crystalline grain. The magnetization of the magnetoelectric multiferroic layer may be axial, canted, or in-plane. For axial or canted magnetization of the magnetoelectric multiferroic layer, a deterministic switching of the free layer may be achieved through coupling with the axial component of magnetization of the magnetoelectric multiferroic layer. Alternatively, the in-plane magnetization of the magnetoelectric multiferroic layer may be employed to induce precession of the magnetization angle of the free layer.

Multiferroic-assisted voltage controlled magnetic anisotropy memory device and methods of manufacturing the same

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 magnetic device includes a first electrode, a second electrode, a plurality of magnetic junctions each containing a ferromagnetic reference layer and a ferromagnetic free layer located between the first electrode and the second electrode, and a plurality of magnetoelectric multiferroic portions having different structural defect densities located between the first electrode and the second electrode. Each of the plurality of magnetoelectric multiferroic portions is magnetically coupled to the ferromagnetic free layer of a respective one of the plurality of magnetic junctions.

Magnetic device including multiferroic regions and methods of forming the same

A magnetoresistive memory device includes a first electrode, a second electrode, and a layer stack located between the first electrode and the second electrode. The layer stack may include a ferroelectric material layer and a metamagnetic tunnel junction containing a metamagnetic material layer, an insulating barrier layer, and a metallic material layer. Alternatively, the layer stack may include a multiferroic material layer, the metamagnetic material layer, the insulating barrier layer, and a reference magnetization layer.

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San Jose, CA, United States of America

Alan Kalitsov