Other

Cadence Design Systems, Inc.

Magic Technologies, Inc.

Advanced Numicro Systems, Inc.

Jun Chen

Yimin Guo

Rongfu Xiao

Chyu-Jiuh Torng

Tom Zhong

Yee-Chung Fu

Wei Cao

Guomin Mao

Gordon Yowell

Duane H Samuelson

Stephen I Kaylor

Hao Ji

Abdelhakim Bouamama

Raja Mitra

David H Gorman

Thomas B Richartz

James A Gayoso

A magnetoresistive element comprises a nonmagnetic nano-current-channel (NCC) structure provided on a surface of the magnetic recording layer, which is opposite to a surface of the magnetic recording layer where the tunnel barrier layer is provided, and comprising a spatial distribution of perpendicular conducting channels throughout the NCC structure thickness and surrounded by an insulating medium, making the magnetic recording layer a magnetically soft-hard composite structure. Correspondingly, the critical write current and write power are reduced with reversal modes of exchange-spring magnets of the magnetically soft-hard composite structure.

Magnetoresistive element having a nano-current-channel structure

The invention comprises a method of forming a novel magnetic pinning structure having a (100) textured or cube-textured reference layer through a non-epitaxial texturing approach so that an excellent coherent tunneling effect is achieved in a pMTJ element due to its texture structure of CoFe BCC (100)/MgO rocksalt (100)/CoFe BCC (100). Correspondingly, a high MR ratio and a high pinning strength on the reference layer can be achieved for perpendicular spin-transfer-torque magnetic-random-access memory (pSTT-MRAM) using perpendicular magnetoresistive elements as basic memory cells which potentially replace the conventional semiconductor memory used in electronic chips, especially mobile chips for power saving and non-volatility.

Perpendicular MTJ element having a cube-textured reference layer and methods of making the same

A magnetoresistive element comprises a nonmagnetic sidewall-current-channel (SCC) structure provided on a surface of the SOT material layer that exhibits the Spin Hall Effect, which is opposite to a surface of the SOT material layer where the magnetic recording layer is provided, and comprising an insulating medium in a central region of the SCC structure, and a conductive medium being a sidewall of the SCC structure and surrounding the insulating medium, making an electric current crowding inside the SOT material layer and the magnetic recording layer to achieve a spin-orbit torque and a higher spin-polarization degree for an applied electric current.

STT-SOT hybrid magnetoresistive element and manufacture thereof

A perpendicular magnetoresistive element comprises (counting from the element bottom): a reference layer having magnetic anisotropy in a direction perpendicular to a film surface and having an invariable magnetization direction; a tunnel barrier layer; a crystalline recording layer having magnetic anisotropy in a direction perpendicular to a film surface and having a variable magnetization direction; an oxide buffer layer; and a cap layer, wherein the crystalline recording layer consists of a CoFe alloy that is substantially free of boron and has BCC (body-centered cubic) CoFe grains having epitaxial growth with (100) plane parallel to a film surface.

Methods of forming perpendicular magnetoresistive elements using sacrificial layers

An ultra-fast magnetic random access memory (MRAM) comprises a three terminal bottom-pinned composite SOT magnetic tunneling junction (bCSOT-MTJ) element including (counting from top to bottom) a magnetic flux guide (MFG) having a very high magnetic permeability, a spin Hall channel (SHC) having a large positive spin Hall angle, an in-plane magnetic memory (MM) layer, a tunnel barrier (TB) layer, and a magnetic pinning stack (MPS) having a synthetic antiparallel coupling pinned by an antiferromagnetic material. The magnetic writing is significantly boosted by a combined effort of enhanced spin orbit torque (SOT) and Lorentz force generated by current-flowing wire (CFW) in the SHC layer and spin transfer torque (STT) by a current flowing through the MTJ stack, and further enhanced by a magnetic close loop formed at the cross section of MFG/SHC/MM tri-layer. Such bCSOT-MTJ element will have a very fast (down to picoseconds) switching speed and consume much less power suitable level 1 or 2 cache application for SMRAM, CPU, GPU and TPU.

Bottom-pinned magnetic random access memory having a composite SOT structure

The invention disclosed a method to make an implanted hard mask with ultra-small dimensions for fabricating integrated nonvolatile random access memory. Instead of directly depositing hard mask material on top of the memory film stack element, we first make ultra-small VIA holes on a pattern transfer molding (PTM) layer using a reverse memory mask, then fill in the hard mask material into the VIA holes within the PTM material. Ultra-small hard mask pillars are formed after removing the PTM material. To improve the adhesion of the hard mask pillars with the underneath memory stack element, a hard mask sustaining element (HMSE) is added below PTM. Due to a better materials adhesion between HMSE and the hard mask, a stronger hard mask array can be formed.

Making a memoristic array with an implanted hard mask

A magnetoresistive element comprises a novel iPMA cap layer on a surface of a ferromagnetic recording layer. The iPMA cap layer introduces giant interfacial magnetic anisotropy energies (G-iMAE) on the interface between the recording layer and the iPMA cap layer, yielding a giant interfacial perpendicular magnetic anisotropy (G-iPMA) of the recording layer.

Magnetoresistive element having a giant interfacial perpendicular magnetic anisotropy

An ultra-fast magnetic random access memory (MRAM) comprises a three terminal composite SOT magnetic tunneling junction (CSOT-MTJ) element including a magnetic flux guide (MFG) having a very high magnetic permeability, a spin Hall channel (SHC) having a large positive spin Hall angle, an in-plane magnetic memory (MM) layer, a tunnel barrier (TB) layer, and a magnetic pinning stack (MPS) having a synthetic antiparallel coupling pinned by an antiferromagnetic material. The magnetic writing is significantly boosted by a combined effort of enhanced spin orbit torque (SOT) and Lorentz force generated by current-flowing wire (CFW) in the SHC layer and spin transfer torque (STT) by a current flowing through the MTJ stack, and further enhanced by a magnetic close loop formed at the cross section of MFG/SHC/MM tri-layer.

Ultra-fast magnetic random access memory having a composite SOT-MTJ structure

The invention comprises a novel composite seed structure (CSS) having lattice constant matched crystalline structure with the Co layer in above perpendicular magnetic pinning layer (pMPL) so that an excellent epitaxial growth of magnetic super lattice pinning layer [Co/(Pt, Pd or Ni)]along its FCC (111) orientation can be achieved, resulting in a significant enhancement of perpendicular magnetic anisotropy (PMA) for perpendicular spin-transfer-torque magnetic-random-access memory (pSTT-MRAM) using perpendicular magnetoresistive elements as basic memory cells which potentially replace the conventional semiconductor memory used in electronic chips, especially mobile chips for power saving and non-volatility.

Composite seed structure to improve PMA for perpendicular magnetic pinning

A magnetoresistive element comprises a novel iPMA cap layer on a surface of a recording layer to induce a giant interfacial perpendicular magnetic anisotropy (G-iPMA) of the recording layer and a method of making the same. The recording layer comprises a first free layer immediately contacting to the tunnel barrier layer and having a body-centered cubic structure with a (100) texture, and a second free layer having a body-centered cubic structure with a (110) texture or a face-centered cubic structure with a (111) texture, and a crystal-breaking layer inserted between the first free layer and the second free layer.

Magnetoresistive element having a giant interfacial perpendicular magnetic anisotropy and method of making the same

A magnetoresistive element using combined spin-transfer-torque controlled magnetic bias and VCMA effects comprising a free layer and an adjacent-bias layer separated by a nonmagnetic spacing layer, wherein the free layer has an interfacial perpendicular magnetic anisotropy and a variable magnetization direction substantially perpendicular to a film surface, the adjacent-bias layer has a perpendicular magnetic anisotropy and a variable magnetization direction substantially perpendicular to a film surface, and the perpendicular anisotropy of the free layer is sufficiently higher than that of the adjacent-bias layer such that the critical switching current to reverse the free layer magnetization direction is at least 3 times as high as the critical switching current to reverse the adjacent-bias layer magnetization direction. Further, there is provided a toggle writing method of the perpendicular magnetoresistive element comprises: applying a first write pulse having a first voltage magnitude and a first pulse width to reverse the adjacent-bias layer magnetization direction to be anti-parallel to the free layer magnetization direction by spin-transfer-torque effect, and applying a second write pulse having a second voltage magnitude and a second pulse width to reverse the free layer magnetization direction to be parallel to the adjacent-bias layer magnetization direction by voltage-controlled magnetic anisotropy effect under the magnetic dipole bias field from the adjacent-bias layer.

Magnetoresistive element having an adjacent-bias layer and a toggle writing scheme

The invention comprises a novel composite multi-stack seed layer (CMSL) having lattice constant matched crystalline structure with the Co layer in above perpendicular magnetic pinning layer (pMPL) so that an excellent epitaxial growth of magnetic super lattice pinning layer [Co/(Pt, Pd or Ni)]along its FCC (111) orientation can be achieved, resulting in a significant enhancement of perpendicular magnetic anisotropy (PMA) for perpendicular spin-transfer-torque magnetic-random-access memory (pSTT-MRAM) using perpendicular magnetoresistive elements as basic memory cells which potentially replace the conventional semiconductor memory used in electronic chips, especially mobile chips for power saving and non-volatility.

Composite multi-stack seed layer to improve PMA for perpendicular magnetic pinning

The present invention discloses an enhanced synthetic antiferromagnetic (eSAF) element with a very strong RKKY coupling comprising a magnetic pinning layer having a face-center-cubic (fcc) crystalline structure and a magnetic reference layer having a body-center-cubic (bcc) crystalline structure which are antiferromagnetically coupled by a composite non-magnetic spacer (CnmS) containing a bi-layer of (Ru, Rh or Ir)/Cr or tri-layer of (Ru, Rh, or Ir)/(W, Mo, or V)/Cr. With such eSAF, a strong magnetic pinning element is formed which can be used to make various thin STT-MRAM film stacks with good thermal and magnetic stability while maintaining high TMR value.

Synthetic magnetic pinning element having strong antiferromagnetic coupling

An approach is described for efficient and accurate signal electromigration analysis of digital-on-top designs with complex interface pin shapes. According to some embodiments, the approach includes performance of parasitic analysis for the interface between nets and primitive/macro cell (blocks). Specifically, the approach includes performing parasitic analysis based on actual location information corresponding to overlap/connection between ports within blocks, external net connections to the ports, and internal net (block net) connections to the port. Thus, by determining the actual locations of the connections (as opposed to a presumed location) the parasitic effects associated with the ports and the connections thereof can be calculated.

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Fremont, CA, United States of America

Jun Chen