Seed layer for enhancing tunnel magnetoresistance with perpendicularly magnetized Heusler films

A method of fabricating a magnetic random access memory (MRAM) stack comprising:

• forming one or more seed layers comprising:
• forming a multi-layer templating structure above a substrate, wherein the multi-layer templating structure includes a crystalline structure configured to enhance a tunnel magnetoresistance (TMR) of the MRAM stack through enhancement of spin polarization of a Heusler compound by improvement of chemical ordering and crystallinity of the Heusler compound, wherein the forming the multi-layer templating structure comprises:
• forming a first layer comprising a binary alloy having a cesium-chloride (CsCl) structure;
• forming a layer of a first binary alloy including tungsten-aluminum (WAI) over the first layer;
• and
• forming a layer of a second binary alloy having a cesium-chloride (CsCl) structure over the WAl layer;
• and
• forming a first magnetic layer comprising:
• templating a Heusler compound through the multi-layer templating structure such that the Heusler compound exhibits perpendicular magnetic anisotropy due at least in part to tetragonal distortion induced by the multi-layer templating structure.

A magnetic random-access memory (MRAM) array, comprising:

• a plurality of bit lines and a plurality of corresponding complementary bit lines forming a plurality of bit line-complementary bit line pairs;
• a plurality of word lines intersecting the plurality of bit line pairs at a plurality of cell locations;
• a plurality of MRAM cells located at each cell location of the plurality of cell locations, each MRAM cell of the plurality of MRAM cells being electrically connected to a corresponding bit line of the plurality of bit lines and selectively interconnected to a corresponding one of the plurality of the complementary bit lines under control of a corresponding one of the word lines of the plurality of word lines, each MRAM cell of the plurality of MRAM cells comprising:
• a first magnetic layer comprising a Heusler compound having perpendicular magnetic anisotropy;
• and
• one or more seed layers comprising:
• a multi-layer templating structure comprising a crystalline structure configured to template the Heusler compound and enhance a tunnel magnetoresistance (TMR) of each MRAM cell of the plurality of MRAM cells through enhancement of spin polarization of the Heusler compound by improvement of chemical ordering and crystallinity of the Heusler compound, wherein the first magnetic layer is formed over the multi-layer templating structure, the multi-layer templating structure comprising:
• a first layer comprising a binary alloy having a cesium-chloride (CsCl) structure;
• a layer of a first binary alloy comprising tungsten-aluminum (WAI) formed over the first layer;
• and
• a second layer of comprising a second binary alloy having a cesium-chloride (CsCl) structure formed over the WAl layer.

A computer system comprising:

• one or more processing devices;
• and
• one or more memory devices communicatively and operably coupled to the one or more processing devices, at least one memory device of the one or more memory devices comprising one or more magnetic random access memory (MRAM) devices, each MRAM device of the one or more MRAM devices comprising:
• a first magnetic layer comprising a Heusler compound having perpendicular magnetic anisotropy;
• and
• one or more seed layers comprising:
• a multi-layer templating structure comprising a crystalline structure configured to template the Heusler compound and enhance a tunnel magnetoresistance (TMR) of each MRAM device of the one or more MRAM devices through enhancement of spin polarization of the Heusler compound by improvement of chemical ordering and crystallinity of the Heusler compound, wherein the first magnetic layer is formed over the multi-layer templating structure, the multi-layer templating structure comprising:
• a first layer comprising a binary alloy having a cesium-chloride (CsCl) structure;
• a layer of a first binary alloy comprising tungsten-aluminum (WAI) formed over the first layer;
• and
• a second layer comprising a second binary alloy having a cesium-chloride (CsCl) structure formed over the WAl layer.

A magnetic random-access memory (MRAM) device, comprising:

• a plurality of MRAM stacks, each MRAM stack of the plurality of MRAM stacks comprising:
• a first magnetic layer comprising a Heusler compound having perpendicular magnetic anisotropy;
• and
• one or more seed layers comprising:
• a multi-layer templating structure comprising a crystalline structure configured to template the Heusler compound and enhance a tunnel magnetoresistance (TMR) of each MRAM stack of the plurality of MRAM stacks through enhancement of spin polarization of the Heusler compound by improvement of chemical ordering and crystallinity of the Heusler compound, wherein the first magnetic layer is formed over the multi-layer templating structure, the multi-layer templating structure comprising:
• a first layer comprising a binary alloy having a cesium-chloride (CsCl) structure;
• a layer of a first binary alloy comprising tungsten-aluminum (WAI) formed over the first layer;
• and
• a layer of a second binary alloy having a cesium-chloride (CsCl) structure formed over the WAl layer.