Thin seeded Co/Ni multilayer film with perpendicular anisotropy for spintronic device applications

A bottom spin valve structure in a spintronic device, comprising:

• (a) a composite seed layer comprising at least a lower Ta layer formed on a substrate and a metal (M1) layer having a fcc(111) or hcp(001) crystal structure disposed on the lower Ta layer;
• (b) a (Co/Ni)x laminated reference layer formed on the composite seed layer, and wherein x is from about 5 to 70 and wherein a thickness (t2) of each Ni layer is greater than a thickness (t1) of each Co layer;
• (c) a tunnel barrier layer formed on the (Co/Ni)x laminated reference layer;
• (d) a magnetic layer having a high spin polarization and a small magnetic damping coefficient formed on the tunnel barrier layer;
• and
• (e) a capping layer formed on the magnetic layer.

A spintronic device for MAMR recording, comprising:

• a first electrode and a second electrode with a stack of layers formed between said first electrode and second electrode, including:
• (a) a composite seed layer comprising at least a lower Ta layer contacting the first electrode and a metal M1 layer having a fcc(111) or hcp(001) crystal orientation disposed on the lower Ta layer opposite the first electrode;
• (b) a (Co/Ni)x laminated layer that serves as a spin injection layer which is formed on the composite seed layer, and wherein x is from about 5 to 70 and wherein a thickness (t2) of each Ni layer is greater than a thickness (t1) of each Co layer;
• (c) a metallic spacer formed between a field generation layer (oscillator layer) and the (Co/Ni)x laminated layer;
• and
• (d) a magnetic layer that serves as an oscillator layer, and having a high spin polarization and a small magnetic damping coefficient formed on the metallic spacer.

A method of forming a spin valve structure in a spintronic device;

• comprising:
• (a) depositing a composite seed layer having a fcc(111) crystalline lattice structure on a substrate, said composite seed layer comprises at least a lower Ta layer and a metal M1 layer having a fcc(111) or hcp(001) crystal orientation disposed on the lower Ta layer;
• (b) forming a stack of layers on said composite seed layer, said stack of layers comprises:
• (1) a (Co/Ni)x laminated reference layer where x is from about 5 to 70 and wherein a thickness (t2) of each Ni layer is greater than a thickness (t1) of each Co layer;
• (2) a magnetic layer having a high spin polarization and a small magnetic damping coefficient, said magnetic layer has a magnetic moment along an easy axis direction that is switched to an opposite direction when a spin torque of sufficient magnitude is applied thereto;
• and
• (3) a metallic spacer or tunnel barrier layer formed between said (Co/Ni)x laminated reference layer and said magnetic layer.