Spin orbit torque (sot) memory devices and methods of fabrication

A method of fabricating a spin orbit torque (SOT) device, the method comprising:

• depositing and planarizing a layer including a spin orbit coupling material;
• depositing a second layer including the spin orbit coupling material over the planarized first layer;
• forming a material layer stack for a magnetic tunnel junction (MTJ) memory device, the forming comprising:
• depositing a fixed magnetic layer;
• depositing a tunnel barrier layer on the fixed magnetic layer;
• and
• depositing a free magnetic layer on the tunnel barrier layer;
• etching the material layer stack, wherein the etching forms a magnetic tunnel junction (MTJ) device;
• and
• etching the second layer including the spin orbit coupling material by using the MTJ device as a mask.

An apparatus comprising:

• a transistor above a substrate, the transistor comprising:
• a drain contact coupled to a drain;
• a source contact coupled to a source;
• a gate contact coupled to a gate;
• and
• a spin orbit torque (SOT) device coupled with the drain contact, the SOT device comprising:
• a fixed magnet;
• a first electrode coupled with the fixed magnet;
• a free magnet;
• a tunnel barrier between the free magnet and the fixed magnet;
• and
• a spin orbit torque (SOT) electrode coupled with the free magnet, the SOT electrode comprising:
• a first layer comprising a spin orbit coupling material, wherein the first layer has a first lateral length;
• and
• a second layer comprising the spin orbit coupling material, wherein:
• the second layer is between the free magnet and the first layer;
• the second layer is in contact with the first layer over a second lateral length that is smaller than the first lateral length;
• and at least a portion of the first layer at an interface with the second layer comprises oxygen;
• and
• a conductive interconnect coupled with the SOT electrode, wherein the MTJ device is laterally between the conductive electrode and the drain contact.