H01F41/30

Magnetic tunnel junction with low defect rate after high temperature anneal for magnetic device applications

A magnetic tunnel junction is disclosed wherein the reference layer and free layer each comprise one layer having a boron content from 25 to 50 atomic %, and an adjoining second layer with a boron content from 1 to 20 atomic %. One of the first and second layers in each of the free layer and reference layer contacts the tunnel barrier. Each boron containing layer has a thickness of 1 to 10 Angstroms and may include one or more B layers and one or more Co, Fe, CoFe, or CoFeB layers. As a result, migration of non-magnetic metals along crystalline boundaries to the tunnel barrier is prevented, and the MTJ has a low defect count of around 10 ppm while maintaining an acceptable TMR ratio following annealing to temperatures of about 400° C. The boron containing layers are selected from CoB, FeB, CoFeB and alloys thereof including CoFeNiB.

Magnetic random access memory and manufacturing method thereof

In a method of manufacturing a semiconductor device, a magnetic random access memory (MRAM) cell structure is formed. The MRAM cell structure includes a bottom electrode, a magnetic tunnel junction (MTJ) stack and a top electrode. A first insulating cover layer is formed over the MRAM cell structure. A second insulating cover layer is formed over the first insulating cover layer. An interlayer dielectric (ILD) layer is formed. A contact opening in the ILD layer is formed, thereby exposing the second insulating cover layer. A part of the second insulating cover layer and a part of the first insulating cover layer are removed, thereby exposing the top electrode. A conductive layer is formed in the opening contacting the top electrode.

Reduction of Capping Layer Resistance Area Product for Magnetic Device Applications
20210367146 · 2021-11-25 ·

A ferromagnetic layer is capped with a metallic oxide (or nitride) layer that provides a perpendicular-to-plane magnetic anisotropy to the layer. The surface of the ferromagnetic layer is treated with a plasma to prevent diffusion of oxygen (or nitrogen) into the layer interior. An exemplary metallic oxide layer is formed as a layer of metallic Mg that is plasma treated to reduce its grain size and enhance the diffusivity of oxygen into its interior. Then the plasma treated Mg layer is naturally oxidized and, optionally, is again plasma treated to reduce its thickness and remove the oxygen rich upper surface.

Magnetic Tunneling Junction with Synthetic Free Layer for SOT-MRAM
20210367143 · 2021-11-25 ·

A magnetic memory device includes a spin-orbit torque (SOT) induction spin Hall electrode and a free layer of a magnetic tunnel junction (MTJ) stack disposed on the spin Hall electrode which is a synthetic anti-ferromagnetic structure. The free layer has a magnetic moment which is askew of the long axis of the MTJ stack and askew the direction of current flow through the spin Hall electrode. The MTJ stack internally generates a magnetic field to switch the state of the free layer. The free layer includes a first layer separated from a second layer by a spacer layer, where the first layer and the second layer may have the same or different crystalline structures.

Multi-layer magnetoelectronic device

A method of producing a multilayer magnetoelectronic device and a related device. The method includes depositing a multilayer structure including at least two ferromagnetic layers disposed one on top of the other and each having a magnetic anisotropy with a corresponding magnetic moment. A magnetization curve is specified for the magnetoelectronic device. The number of ferromagnetic layers and, for each of the ferromagnetic layers, the magnetic moment and the magnetic hardness for obtaining the specified magnetization curve are determined. For each of the ferromagnetic layers a magnetic material, a thickness, an azimuthal angle and an angle of incidence are determined for obtaining the determined magnetic moment and magnetic hardness of the respective ferromagnetic layer. The multilayer structure is deposited using the determined material, thickness, azimuthal angle and angle of incidence for each of the ferromagnetic layers.

Method of processing workpiece
11171286 · 2021-11-09 · ·

There is provided a method of processing a workpiece for manufacturing a magnetoresistive effect element, the workpiece including a first multilayer film and a second multilayer film, the first multilayer film including a first magnetic layer, a second magnetic layer and a tunnel barrier layer formed between the first magnetic layer and the second magnetic layer, and the second multilayer film constituting a pinning layer in the magnetoresistive effect element. The method includes etching the first multilayer film and the second multilayer film, and heating the workpiece after the etching or during the etching. The heating includes heating the workpiece while adjusting an ambient condition of the workpiece.

Magnetic sensor bias point adjustment method

The present disclosure generally relates to a Wheatstone bridge that has four resistors. Each resistor includes a plurality of TMR structures. Two resistors have identical TMR structures. The remaining two resistors also have identical TMR structures, though the TMR structures are different from the other two resistors. Additionally, the two resistors that have identical TMR structures have a different amount of TMR structures as compared to the remaining two resistors that have identical TMR structures. Therefore, the working bias field for the Wheatstone bridge is non-zero.

MAGNETORESISTIVE STACK DEVICE FABRICATION METHODS
20210343936 · 2021-11-04 · ·

A method of fabricating a magnetoresistive device may comprise forming an electrically conductive region and forming a first seed region on one side of the electrically conductive region. A surface of the first seed region may be treated by exposing the surface to a gas. A second seed region may be formed on the treated surface of the first seed region. The method may also comprise forming a magnetically fixed region on one side of the second seed region.

Magnetoresistive sensors and methods for generating closed flux magnetization patterns

A method for generating a closed flux magnetization pattern of a predetermined rotational direction in a magnetic reference layer of a magnetic layer stack is provided. The method includes applying an external magnetic field in a predetermined direction to the magnetic layer stack causing magnetic saturation of the magnetic reference layer and of a pinned layer of the magnetic layer stack; and reducing the external magnetic field to form a first closed flux magnetization pattern in the magnetic reference layer and a second closed flux magnetization pattern in the pinned layer.

Ferrimagnetic Heusler compounds with high spin polarization

A magnetic device and method for providing the magnetic device are disclosed. The magnetic device includes a multilayer structure and a magnetic layer. The multilayer structure includes alternating layers of A and E. A includes a first material. The first material includes at least one of Co, Ru, or Ir. The first material may include an IrCo alloy. E includes at least one other material that includes Al. The other material(s) may include an alloy selected from AlGa, AlSn, AlGe, AlGaGe, AlGaSn, AlGeSn, and AlGaGeSn. A composition of the multilayer structure is represented by A.sub.1-xE.sub.x, where x is at least 0.45 and not more than 0.55. The magnetic layer includes an Al-doped Heusler compound. The magnetic layer shares an interface with the multilayer structure.