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.

A magnetic memory element including first and second magnetic free layers having a variable magnetization direction substantially perpendicular to layer planes thereof; a first perpendicular enhancement layer (PEL) interposed between the first and second magnetic free layers; first and second magnetic reference layers having a first invariable magnetization direction substantially perpendicular to layer planes thereof; a second PEL interposed between the first and second magnetic reference layers; an insulating tunnel junction layer formed between the first magnetic free layer and reference layer; an anti-ferromagnetic coupling layer formed adjacent to the second magnetic reference layer; a magnetic fixed layer formed adjacent to the anti-ferromagnetic coupling layer and having a second invariable magnetization direction substantially opposite to the first invariable magnetization direction; a non-magnetic layer comprising oxygen and a transition metal and formed adjacent to the second magnetic free layer; and a magnesium oxide layer formed adjacent to the non-magnetic layer.

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.

A method of manufacturing an MRAM device, the method including forming a first magnetic layer on a substrate; forming a first tunnel barrier layer on the first magnetic layer such that the first tunnel barrier layer includes a first metal oxide, the first metal oxide being formed by oxidizing a first metal layer at a first temperature; forming a second tunnel barrier layer on the first tunnel barrier layer such that the second tunnel barrier layer includes a second metal oxide, the second metal oxide being formed by oxidizing a second metal layer at a second temperature that is greater than the first temperature; and forming a second magnetic layer on the second tunnel barrier layer.

The present invention is directed to a magnetic memory element including a magnetic free layer structure incorporating three magnetic free layers separated by two perpendicular enhancement layers (PELs) and having a variable magnetization direction substantially perpendicular to layer planes thereof; an insulating tunnel junction layer formed adjacent to the magnetic free layer structure; a first magnetic reference layer formed adjacent to the insulating tunnel junction layer opposite the magnetic free layer structure; a second magnetic reference layer separated from the first magnetic reference layer by a third perpendicular enhancement layer; an anti-ferromagnetic coupling layer formed adjacent to the second magnetic reference layer; and a magnetic fixed layer formed adjacent to the anti-ferromagnetic coupling layer. The first and second magnetic reference layers have a first invariable magnetization direction substantially perpendicular to layer planes thereof. The magnetic fixed layer has a second invariable magnetization direction substantially opposite to the first invariable magnetization direction.

A magnetoresistive sensor includes a magnetic reference layer. The magnetic reference layer includes a permanent closed flux magnetization pattern of a predetermined rotational direction. Furthermore, the magnetoresistive sensor includes a magnetic free layer. The magnetic free layer has a total lateral area that is smaller than a total lateral area of the magnetic reference layer. A centroid of the magnetic free layer is laterally displaced with respect to a centroid of the magnetic reference layer.

A spintronic device controls both the electrical charge and the spin of electrons to transmit, process, and store information. The control of electron spin provides additional degrees of freedom to modify the electric and magnetic properties of materials such as magnetic anisotropy. However, the development and integration of spintronic devices has been limited, in part, by the lack of a robust approach to electrically gate magnetism. Conventional approaches to gating magnetism either exhibit impractically small changes to the properties of a magnet or limited operating lifetime due to material degradation. Here, a magneto-ionic device operates using a hydrogen-gated magneto-ionic mechanism to overcome these shortcomings. A gate voltage applied to the magneto-ionic device causes protons to move towards a magnetic layer where the protons reduce to hydrogen. The presence of hydrogen and protons leads to large changes in the magnetic layer without degradation. This voltage-induced process is reversible.

A magnetic tunnel junction (MTJ) is disclosed wherein first and second interfaces of a free layer (FL) with a first metal oxide (Hk enhancing layer) and second metal oxide (tunnel barrier), respectively, produce perpendicular magnetic anisotropy (PMA) to increase thermal stability. In some embodiments, a capping layer that is a conductive metal nitride such as MoN contacts an opposite surface of the Hk enhancing layer with respect to the first interface to reduce interdiffusion of oxygen and nitrogen compared with a TiN capping layer and maintain an acceptable resistance×area (RA) product. In other embodiments, the capping layer may comprise an insulating nitride such as AlN that is alloyed with a conductive metal to minimize RA. Furthermore, a metallic buffer layer may be inserted between the capping layer and Hk enhancing layer. As a result, electrical shorts are reduced and the magnetoresistive ratio is increased.

The present disclosure relates to a spin-orbit torque-based switching device and a method of fabricating the same. The spin-orbit torque-based switching device of the present disclosure includes a spin torque generating layer provided with a tungsten-vanadium alloy thin film exhibiting perpendicular magnetic anisotropy (PMA) characteristics and a magnetization free layer formed on the spin torque generating layer.

A magnetic tunnel junction stack includes: a pinned layer; a main oxide barrier layer on the pinned layer; a free layer on the main oxide barrier layer; and a hybrid oxide/metal cap layer on the free layer. The hybrid oxide/metal cap layer includes: a first oxide layer on the free layer; a second oxide layer on the first oxide layer; and a metallic cap layer on the second oxide layer, wherein the free layer is free of boron (B).