Magnetic element with perpendicular magnetic anisotropy for high coercivity after high temperature annealing

A magnetic memory element formed between a first electrode and a second electrode, comprising:

• (a) a tunnel barrier layer that forms a first interface with a first surface of a free layer and thereby induces or enhances perpendicular magnetic anisotropy (PMA) in the free layer;
• (b) the free layer;
• (c) a reference layer that contacts a side of the tunnel barrier that is opposite the first interface;
• (d) an Hk enhancing layer which is a metal oxide that forms a second interface with the free layer at a second surface thereof that is opposite the first surface, and thereby induces or enhances PMA in the free layer;
• (e) a first non-magnetic diffusion barrier formed between the Hk enhancing layer and the first electrode;
• and
• (f) a second non-magnetic diffusion barrier formed between the reference layer and the second electrode, each of the first and second non-magnetic diffusion barriers comprises at least one of SiN, TIN, Mo, W, Cr, V, or CoaFebXc or CoFeNiX wherein X is one of Zr, Hf, Nb, Cu, Mo, B, P, and Ta, and (a+b+c)=100 atomic %.

A method of forming a magnetic memory element with a stack of layers, comprising:

• (a) depositing a reference layer above a substrate;
• (b) forming a tunnel barrier on the reference layer;
• (c) depositing a free layer that contacts a top surface of the tunnel barrier to form a first interface which induces or enhances perpendicular magnetic anisotropy (PMA) in the free layer;
• (d) forming a metal oxide layer that contacts a top surface of the free layer to form a second interface that induces or enhances PMA in the free layer;
• (e) depositing a non-magnetic diffusion barrier on the metal oxide layer, the non-magnetic diffusion barrier comprises at least one of SiN, TiN, Mo, W, Cr, V, or CoaFebXc or CoFeNiX wherein X is one of Zr, Hf, Nb, Cu, Mo, B, P, and Ta, and (a+b+c)=100 atomic %;
• (f) forming a hard mask on the non-magnetic diffusion barrier;
• and
• (g) annealing the stack of layers.

A method of forming a magnetic memory element with a stack of layers, comprising:

• (a) depositing a non-magnetic diffusion barrier over a substrate, the non-magnetic diffusion barrier comprises at least one of SiN, TiN, Mo, W, Cr, V, or CoaFebXc or CoFeNiX wherein X is one of Zr, Hf, Nb, Cu, Mo, B, P, and Ta, and (a+b+c)=100 atomic %;
• (b) forming a metal oxide layer on the non-magnetic diffusion barrier;
• (c) depositing a free layer that contacts a top surface of the metal oxide layer to form a first interface which induces or enhances perpendicular magnetic anisotropy (PMA) in the free layer;
• (d) forming a tunnel barrier that contacts a top surface of the free layer to form a second interface that induces or enhances PMA in the free layer;
• (e) depositing a reference layer on the tunnel barrier;
• (f) forming a hard mask on the reference layer;
• and
• (g) annealing the stack of layers at a temperature of about 400° C.