Coaxial top mram electrode
AssigneeInternational Business Machines Corporation
InventorsOscar van der Straten, Koichi Motoyama, Chih-Chao Yang
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Abstract
Embodiments of the invention include a semiconductor structure with a first magneto-resistive random access memory (MRAM) pillar with a bottom electrode layer, a reference layer connected above the bottom electrode layer, a free layer, and a tunnel barrier between the reference layer and the free layer. The MRAM pillar includes a pillar diameter. The semiconductor structure also includes a coaxial top electrode with a top diameter that is less than the pillar diameter.
Claims20
A semiconductor structure, comprising:
- a first magneto-resistive random access memory (MRAM) pillar, comprising:
- a bottom electrode layer;
- a reference layer connected above the bottom electrode layer;
- a free layer;
- and
- a tunnel barrier between the reference layer and the free layer, wherein the MRAM pillar comprises a pillar diameter;
- and
- a coaxial top electrode comprising a top diameter that is less than the pillar diameter.
A method of fabricating a magneto-resistive random access memory (MRAM) device, comprising:
- forming a bottom electrode layer, a reference layer connected above the bottom electrode layer, a free layer, and a tunnel barrier between the reference layer and the free layer;
- forming a first coaxial top electrode surrounded by a first conformal dielectric, wherein the coaxial top electrode comprises a top diameter and the conformal dielectric comprises a pillar diameter;
- etching the bottom electrode layer, the reference layer, the free layer, and the tunnel barrier to form an MRAM pillar, wherein the first conformal dielectric masks the bottom electrode layer, the reference layer, the free layer, and the tunnel barrier;
- removing the conformal dielectric;
- and
- forming an inter-level dielectric (ILD) around the MRAM pillar and the top electrode.
A semiconductor structure, comprising:
- a first magneto-resistive random access memory (MRAM) pillar comprising:
- a first body comprising a first pillar diameter;
- and
- a first coaxial top electrode comprising a first top diameter that is smaller than the first pillar diameter;
- a second MRAM pillar adjacent to the first MRAM pillar comprising:
- a second body comprising a second pillar diameter;
- and
- a second coaxial top electrode comprising a second top diameter that is smaller than the second pillar diameter;
- and
- an inter-level dielectric (ILD) between the first MRAM pillar and the second MRAM pillar.
Dependencies are inferred from the claim text.