Seagate Technology Incorporated

Xiaohua Lou

Haiwen Xi

Yuankai Zheng

Dimitar Velikov Dimitrov

Wei Tian

Zheng Gao

Wenzhong Zhu

Yiran Chen

Xiaobin Wang

Dexin Wang

Olle Gunnar Heinonen

Michael Xuefei Tang

Yong Lu

Wonjoon Jung

Alan Xuguang Wang

Xuebing Feng

Song Sheng Xue

An apparatus and associated method for a non-volatile memory cell with a phonon-blocking insulating layer. In accordance with various embodiments, a magnetic stack has a tunnel junction, ferromagnetic free layer, pinned layer, and an insulating layer that is constructed of an electrically and thermally insulative material that blocks phonons while allowing electrical transmission through at least one conductive feature.

Memory cell with phonon-blocking insulating layer

A memory unit includes a magnetic tunnel junction data cell electrically coupled to a bit line and a word line. The magnetic tunnel junction data cell is configured to switch between a high resistance state and a low resistance state by passing a unipolar voltage across the magnetic tunnel junction data cell. A diode is electrically coupled between the magnetic tunnel junction data cell and the word line or bit line. A voltage source provides the unipolar voltage across the magnetic tunnel junction data cell that writes the high resistance state and the low resistance state.

Unipolar spin-transfer switching memory unit

A magnetic stack having a ferromagnetic free layer, a metal oxide layer that is antiferromagnetic at a first temperature and non-magnetic at a second temperature higher than the first temperature, a ferromagnetic pinned reference layer, and a non-magnetic spacer layer between the free layer and the reference layer. During a writing process, the metal oxide layer is non-magnetic. For magnetic memory cells, such as magnetic tunnel junction cells, the metal oxide layer provides reduced switching currents.

Magnetic stack with oxide to reduce switching current

A magnetic tunnel junction having a ferromagnetic free layer and a ferromagnetic pinned reference layer, each having an out-of-plane magnetic anisotropy and an out-of-plane magnetization orientation, the ferromagnetic free layer switchable by spin torque. The magnetic tunnel junction includes a ferromagnetic assist layer proximate the free layer, the assist layer having a low magnetic anisotropy less than 700 Oe and positioned to apply a magnetic field on the free layer.

Magnetic stack having assist layers

A magnetic tunnel junction memory cell includes a ferromagnetic reference layer, a ferromagnetic free layer, and a non-magnetic barrier layer separating the ferromagnetic reference layer from the ferromagnetic free layer. The magnetic tunnel junction cell has an asymmetric energy barrier for switching between a high resistance data state and a low resistance data state. Memory devices and methods are also described.

Magnetic memory with asymmetric energy barrier

A staggered magnetic tunnel junction includes a free magnetic layer extending in a lateral direction between a first end portion and an opposing second end portion and a tunneling barrier disposed between a reference magnetic layer and the first end portion and forming a magnetic tunnel junction. Current flows through the free magnetic layer in the lateral direction to switch the magnetic tunnel junction between a high resistance state and a low resistance state.

Staggered magnetic tunnel junction

A magnetic tunnel junction having a compsensation element is disclosed. The magnetic tunnel junction includes a reference element, and a compensation element having an opposite magnetization moment to a magnetization moment of the reference element. A free magnetic layer is between the reference element and the compensation element, and an electrically insulating and non-magnetic tunneling barrier layer separates the free magnetic layer from the reference element. The free magnetic layer includes CoFeBwherein X is a value being greater than 30 and Y is a value being greater than 15.

Magnetic tunnel junction with compensation element

Apparatus and associated method for writing data to a non-volatile memory cell, such as spin-torque transfer random access memory (STRAM). In accordance with some embodiments, a resistive sense element (RSE) has a heat assist region, magnetic tunneling junction (MTJ), and pinned region. When a first logical state is written to the MTJ with a spin polarized current, the pinned and heat assist regions each have a substantially zero net magnetic moment. When a second logical state is written to the MTJ with a static magnetic field, the pinned region has a substantially zero net magnetic moment and the heat assist region has a non-zero net magnetic moment.

Static magnetic field assisted resistive sense element

Magnetic stack having assist layer

An apparatus and method for compensating for asymmetric write current in a non-volatile unit cell. The unit cell comprises a switching device and an asymmetric resistive sense element (RSE), such as an asymmetric resistive random access memory (RRAM) element or an asymmetric spin-torque transfer random access memory (STRAM) element. The RSE is physically oriented within the unit cell relative to the switching device such that a hard direction for programming the RSE is aligned with an easy direction of programming the unit cell, and an easy direction for programming the RSE is aligned with a hard direction for programming the unit cell.

Asymmetric write current compensation

Non-volatile magnetic random access memory (MRAM) devices that include magnetic flip-flop structures that include a magnetization controlling structure; a first tunnel barrier structure; and a magnetization controllable structure that includes a first polarizing layer; and a first stabilizing layer, wherein the first tunnel barrier structure is between the magnetization controllable structure and the magnetization controlling structure and the first polarizing layer is between the first stabilizing layer and the first tunnel barrier structure, wherein the magnetic flip-flop device has two stable overall magnetic; configurations a second tunnel barrier structure and a reference layer, wherein the second tunnel barrier structure is between the magnetic flip-flop device and the reference layer.

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Bloomington, MN, United States of America

Xiaohua Lou