A multilayer thin film for magnetic random access memory that includes thin platinum layers and thin cobalt-copper layers, and more particularly, to a multilayer thin film having magnetic layers including non-magnetic material copper that replaces a portion of the magnetic material cobalt.

Variable resistance elements and semiconductor devices including the variable resistance elements are disclosed. In some implementations, a variable resistance element may include a variable resistance element may include a free layer having a variable magnetization direction that switches between different magnetization directions upon application of a magnetic field, a pinned layer having a fixed magnetization direction, and a tunnel barrier layer interposed between the free layer and the pinned layer and including a metal chalcogenide having a cubic crystal structure.

In one embodiment, a spin torque device uses a thick (e.g., >1 nm, and preferably >=2-6 nm) ferrimagnet (FIM) layer, instead of a thin (e.g., <1-2 nm) FM layer in the device's stack. The FIM layer may be composed of a cobalt-gadolinium (CoGd) alloy, cobalt-terbium (CoTb) multilayers, or other materials that provide anti-ferromagnetic coupling between two sub-lattices. Negative exchange interaction between the two sub-lattices of the FIM may allow for low current switching. High thermal stability and external magnetic field resistance may also be achieved.

The present invention is directed to a magnetic tunnel junction (MTJ) memory element including a magnetic free layer structure and a magnetic reference layer structure with an insulating tunnel junction layer interposed therebetween; a magnetic fixed layer exchange coupled to the magnetic reference layer structure through an anti-ferromagnetic coupling layer; a magnesium oxide layer formed adjacent to the magnetic fixed layer; and a metal layer comprising nickel and chromium formed adjacent to the magnesium oxide layer. The magnetic reference layer structure includes a first and a second magnetic reference layers with a first perpendicular enhancement layer (PEL) interposed therebetween. 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 opposite to the first invariable magnetization direction. The magnetic free layer structure includes one or more magnetic free layers having a variable magnetization direction substantially perpendicular to layer planes thereof.

The invention relates to heterostructures including a layer of a two-dimensional material placed on a multiferroic layer. An ordered array of differing polarization domains in the multiferroic layer produces corresponding domains having differing properties in the two-dimensional material. When the multiferroic layer is ferroelectric, the ferroelectric polarization domains in the layer produce local electric fields that penetrate the two-dimensional material. The local electric fields can influence properties of the two-dimensional material, including carrier density, transport properties, optical properties, surface chemistry, piezoelectric-induced strain, magnetic properties, and interlayer spacing. Methods for producing the heterostructures are provided. Devices incorporating the heterostructures are also provided, including tunable sensors, optical emitters, and programmable logic gates.

In one embodiment, a spin torque device uses a thick (e.g., >1 nm, and preferably >=2-6 nm) ferrimagnet (FIM) layer, instead of a thin (e.g., <1-2 nm) FM layer in the device's stack. The FIM layer may be composed of a cobalt-gadolinium (CoGd) alloy, cobalt-terbium (CoTb) multilayers, or other materials that provide anti-ferromagnetic coupling between two sub-lattices. Negative exchange interaction between the two sub-lattices of the FIM may allow for low current switching. High thermal stability and external magnetic field resistance may also be achieved.

A topological spin memory effect, defined as the recovery of magnetic skyrmions or magnetic bubble skyrmions in magnetic thin films after a transition to a dramatically different spin texture, is used for encrypted non-volatile information storage. The storage strategy is based on magnetic skyrmions, that is, topologically protected spin textures comprising chiral domain walls surrounding small (e.g., nanometers to microns in diameter), typically circular, single-domain cores. Systems and methods are described for encrypted non-volatile information storage based on a spin memory effect in magnetic thin films that support skyrmions. Systems and methods encrypt and recover information stored in the form of magnetic skyrmions.

The present invention is directed to a magnetic tunnel junction (MTJ) memory element including a magnetic free layer structure and a magnetic reference layer structure with an insulating tunnel junction layer interposed therebetween; a magnetic fixed layer exchange coupled to the magnetic reference layer structure through an anti-ferromagnetic coupling layer; a magnesium oxide layer formed adjacent to the magnetic fixed layer; and a metal layer comprising nickel and chromium formed adjacent to the magnesium oxide layer. The magnetic reference layer structure includes a first and a second magnetic reference layers with a first perpendicular enhancement layer (PEL) interposed therebetween. 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 opposite to the first invariable magnetization direction. The magnetic free layer structure includes one or more magnetic free layers having a variable magnetization direction substantially perpendicular to layer planes thereof.

The present invention is directed to an STT-MRAM device comprising a plurality of memory elements. Each of the memory elements includes an MTJ structure that comprises a magnetic free layer structure and a magnetic reference layer structure with an insulating tunnel junction layer interposed therebetween; a first perpendicular enhancement layer (PEL) formed adjacent to the magnetic free layer structure; a magnetic dead layer formed adjacent to the first PEL; and a magnetic fixed layer exchange coupled to the magnetic reference layer structure through an anti-ferromagnetic coupling layer. The magnetic reference layer structure includes a first magnetic reference layer formed adjacent to the insulating tunnel junction layer and a second magnetic reference layer separated from the first magnetic reference layer by a second PEL. The first and second magnetic reference layers have a first invariable magnetization direction substantially perpendicular to layer planes thereof.

Embodiments of the disclosure provide methods and apparatus for fabricating magnetic tunnel junction (MTJ) structures on a substrate in for spin-transfer-torque magnetoresistive random access memory (STT-MRAM) applications. In one example, a film stack utilized to form a magnetic tunnel junction structure on a substrate includes a pinned layer disposed on a substrate, wherein the pinned layer comprises multiple layers including at least one or more of a Co containing layer, Pt containing layer, Ta containing layer, an Ru containing layer, an optional structure decoupling layer disposed on the pinned magnetic layer, a magnetic reference layer disposed on the optional structure decoupling layer, a tunneling barrier layer disposed on the magnetic reference layer, a magnetic storage layer disposed on the tunneling barrier layer, and a capping layer disposed on the magnetic storage layer.