International Business Machines Corporation

Virat Vasav Mehta

Eric Raymond Evarts

Alexander Reznicek

Pouya Hashemi

Michael Rizzolo

Chandrasekharan Kothandaraman

Saba Zare

Bahman Hekmatshoartabari

Oscar Van Der Straten

Provided is a magnetoresistive random-access memory (MRAM) cell. The MRAM cell comprises a top contact, a hard mask layer below the top contact, and a magnetic tunnel junction (MTJ) below the hard mask layer. The MRAM cell further comprises a diffusion barrier below the MTJ, a bottom contact below the diffusion barrier, and a magnetic liner arranged around the bottom contact.

Selectively biasing magnetoresistive random-access memory cells

A spin-orbit torque magnetoresistive random-access memory device formed by fabricating a spin-Hall-effect (SHE) layer above and in electrical contact with a transistor, forming a spin-orbit-torque (SOT) magnetoresistive random access memory (MRAM) cell stack disposed above and in electrical contact with the SHE rail, wherein the SOT-MRAM cell stack comprises a free layer, a tunnel junction layer, a reference layer, and a diode structure, forming a write line disposed in electrical contact with the SHE rail, forming a protective dielectric layer covering a portion of the SOT-MRAM cell stack, and forming a read line disposed above and adjacent to the diode structure.

Spin-orbit-torque magnetoresistive random-access memory

An embodiment of the invention may include a magnetic random-access memory (MRAM) structure and method of making the structure. The MRAM structure may include a magnetic tunnel junction stack. The MRAM structure may include a magnetic liner located between the magnetic tunnel junction stack and a top contact, where the magnetic liner may be a ferromagnetic material. This may enable the magnetic liner to act as an independent variable to balance many of the magnetic parameters in the MTJ film stack in order to achieve zero magnetic field at the MTJ layer.

MRAM containing magnetic top contact

A sub-micrometer pressure sensor is provided that includes a multilayered magnetic tunnel junction (MTJ) pillar that contains a non-magnetic metallic spacer separating a first magnetic free layer from a second magnetic free layer. The presence of the non-magnetic metallic spacer in the multilayered MTJ pillar improves the sensitivity without compromising area, and makes the pressure sensor binary (either 'on' or 'off') with little or no drift, and sensitivity change over time. Moreover, the resistivity switch in such a pressure sensor is instantly and a low error rate is observed.

Multilayered magnetic free layer structure in magnetic tunnel junction arrays for sub-micrometer resolution pressure sensors

A method of manufacturing a double magnetic tunnel junction device is provided. The method includes forming a first magnetic tunnel junction stack. The first magnetic tunnel junction stack includes a first reference layer. The method also includes forming a second magnetic tunnel junction stack, where the second magnetic tunnel junction stack includes a second reference layer. The method also includes bonding the first magnetic tunnel junction stack to the second magnetic tunnel junction stack with ultra-high vacuum bonding to form the double magnetic tunnel junction device.

Double magnetic tunnel junction device, formed by UVH wafer bonding

An erasable magnetoresistive random-access memory (MRAM) structure and a method of making the same includes an MRAM cell disposed between bit line and word line circuit elements, and a vertical-cavity surface-emitting laser (VCSEL) element disposed above the MRAM cell. A laser output of the VCSEL is directed toward the MRAM cell.

Nanosecond non-destructively erasable magnetoresistive random-access memory

A sub-micrometer pressure sensor including a multilayered magnetic tunnel junction (MTJ) pillar containing a magnetostrictive material layer above or below a magnetic free layer of the multilayered MTJ pillar is provided. Advanced patterning allows for scaling of the multilayered MTJ pillar down to 25 nm or below which enables the formation of a large array of extremely high resolution pressure sensors. By varying the thickness of the magnetostrictive material layer, the sensitivity of the pressure sensor can be fine tuned. Unique magnetostrictive materials in the multilayered MTJ pillar will alter the device current with the input of external pressure. Furthermore, unique arrays with much smaller critical elements can be organized in differential sensing arrangements of the multilayered MTJ pillar with pressure sensing capability that can outperform current piezoelectric based pressure sensing arrays.

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Menands, NY, United States of America

Virat Vasav Mehta