International Business Machines Corporation

Samsung Electronics Co., Ltd.

Industrial Technology Research Institute

Guohan Hu

Daniel Christopher Worledge

Jonathan Zanhong Sun

Jeong-Heon Park

Younghyun Kim

Stephen L Brown

Naigang Wang

Luqiao Liu

Cheng-Wei Chien

Alexander Reznicek

Chandrasekara Kothandaraman

Kwangseok Kim

Junghyuk Lee

Matthias Georg Gottwald

Pouya Hashemi

David William Abraham

Philip Louis Trouilloud

Janusz Jozef Nowak

Yu Lu

Saba Zare

Jung-Hyuk Lee

Jonathan Zanghong Sun

A memory device including a pedestal structure containing a cobalt aluminum layer and a magnesium-aluminum-oxide containing base layer both of which have a (001) crystal orientation is provided. The memory device further includes a magnetic tunnel junction (MTJ) pillar containing an ordered alloy forming an interface with the cobalt aluminum alloy layer. The use of the structural and textural engineered pedestal structure provides improved control of resistance, as well as improved magnetic properties such as higher tunnel magnetoresistance (TMR) and higher perpendicular magnetic anisotropy (PMA), and closer distribution of the ordered alloy.

Textured cobalt aluminum/magnesium-aluminum-oxide pedestal for memory devices

A semiconductor device that includes a substrate, a crystalline bottom electrode layer on an upper side of the semiconductor substrate, a conductive crystalline metal layer above the crystalline bottom electrode layer, and a conductive oxide layer above the conductive crystalline metal layer. The conductive oxide layer has a low resistance. The semiconductor device also includes a magnetic tunnel junction (MTJ) above the conductive crystalline metal layer, the MTJ including a tunnel barrier layer, a free layer on a first side of the tunnel barrier layer and a reference layer on a second side of the tunnel barrier layer opposite the first side.

Reactive serial resistance reduction for magnetoresistive random-access memory devices

Embodiments of the invention are directed to a magnetic tunnel junction (MTJ) storage element that includes a reference layer, a tunnel barrier and a free layer on an opposite side of the tunnel barrier layer from the reference layer. The reference layer has a fixed magnetization direction. The free layer includes a first region, a second region and a third region. The third region is formed from a third material that is configured to magnetically couple the first region and the second region. The first region is formed from a first material having a first predetermined magnetic moment, and the second region is formed from a second material having a second predetermined magnetic moment. The first predetermined magnetic moment is lower that the second predetermined magnetic moment.

Magnetic exchange coupled MTJ free layer having low switching current and high data retention

A modified double magnetic tunnel junction (mDMTJ) structure is provided which includes a narrow base and the use of a spin diffusion layer (i.e., non-magnetic, spin-conducting metallic layer) which gives a low resistance-area product (RA) for the tunnel barrier layer that forms an interface with the spin diffusion layer.

Low RA narrow base modified double magnetic tunnel junction structure

A memory structure, i.e., magnetoresistive random access memory (MRAM) structure, is provided that includes a seeding area including at least a tunnel barrier seed layer located beneath a chemical templating layer that is wider than the magnetic tunnel junction (MTJ) structure that is located on the chemical templating layer. Redeposited metallic material is located on at least a sidewall of the tunnel barrier seed layer of the seeding area so as to shunt that area of the structure. The memory structure has reduced resistance with minimal tunnel magnetoresistance (TMR) loss penalty.

MRAM structure with enhanced magnetics using seed engineering

A multilayered magnetic free layer structure is provided that includes a first magnetic free layer and a second magnetic free layer separated by a non-magnetic layer in which the first magnetic free layer is composed of an ordered magnetic alloy. The ordered magnetic alloy provides a first magnetic free layer that has low moment, but is strongly magnetic. The use of such an ordered magnetic alloy first magnetic free layer in a multilayered magnetic free layer structure substantially reduces the switching current needed to reorient the magnetization of the two magnetic free layers.

Multilayered magnetic free layer structure containing an ordered magnetic alloy first magnetic free layer for spin-transfer torque (STT) MRAM

A method for forming a memory device that includes providing a free layer of an alloy of cobalt (Co), iron (Fe) and boron (B) overlying a reference layer; and forming metal layer comprising a boron (B) sink composition atop the free layer. Boron (B) may be diffused from the free layer to the metal layer comprising the boron sink composition. At least a portion of the metal layer including the boron (B) sink composition is removed. A metal oxide is formed atop the free layer. The free layer may be a crystalline cobalt and iron alloy. An interface between the metal oxide and free layer can provide perpendicular magnetic anisotropy character.

In-situ annealing and etch back steps to improve exchange stiffness in cobalt iron boride based perpendicular magnetic anisotropy free layers

A modified double magnetic tunnel junction structure is provided which includes an amorphous spin diffusion layer (i.e., an amorphous non-magnetic, spin-conducting metallic layer) sandwiched between a magnetic free layer and a first tunnel barrier layer; the first tunnel barrier layer contacts a first magnetic reference layer. A second tunnel barrier layer is located on the magnetic free layer and a second magnetic reference layer is located on the second tunnel barrier layer. Such a modified double magnetic tunnel junction structure exhibits efficient switching (at a low current) and speedy readout (high tunnel magnetoresistance).

Amorphous spin diffusion layer for modified double magnetic tunnel junction structure

A planar magnetic structure includes a closed loop structure having a plurality of core segments divided into at least two sets. A coil is formed about one or more core segments. A first antiferromagnetic layer is formed on a first set of core segments, and a second antiferromagnetic layer is formed on a second set of core segments. The first and second antiferromagnetic layers include different blocking temperatures and have an easy axis pinning a magnetic moment in two different directions, wherein when current flows through the coil, the magnetic moments rotate to form a closed magnetic loop in the closed loop structure.

Planar solenoid inductors with antiferromagnetic pinned cores

A bottom pinned magnetic tunnel junction (MTJ) stack having improved switching performance is provided which can be used as a component/element of a spin-transfer torque magnetoresistive random access memory (STT MRAM) device. The improved switching performance which, in turn, can reduce write errors and improve write voltage distributions, is obtained by inserting at least one heavy metal-containing layer into the magnetic free layer and/or by forming a heavy metal-containing layer on a MTJ capping layer that is located above the magnetic free layer.

STT MRAM matertails with heavy metal insertion

A multilayered magnetic free layer structure is provided that includes a first magnetic free layer and a second magnetic free layer separated by a non-magnetic layer in which the second magnetic free layer is composed of a M/Msuperlattice structure or a M/Mmultilayer structure, wherein Mis a first magnetic metal selected from the group consisting of cobalt (Co), iron (Fe) and alloys thereof, and Mis a second magnetic metal selected from the group consisting of platinum (Pt), palladium (Pd), nickel (Ni), rhodium (Rh), iridium (Jr), rhenium (Re) and alloys thereof.

Multilayered magnetic free layer structure for spin-transfer torque (STT) MRAM

Method for forming a planar solenoid inductor

Techniques relate to forming a magnetic tunnel junction (MTJ). A synthetic antiferromagnetic reference layer is adjacent to a tunnel barrier layer. The synthetic antiferromagnetic reference layer includes a first magnetic layer, a second magnetic layer, and a reference spacer layer sandwiched between the first magnetic layer and the second magnetic layer. A magnetic free layer is adjacent to the tunnel barrier layer so as to be opposite the synthetic antiferromagnetic reference layer. The synthetic antiferromagnetic reference layer has a thickness of at least one of 3 nanometers (nm), 4 nm, and 3-4 nm.

Thin reference layer for STT MRAM

A magnetoresistive random access memory device (MRAM) device is described. The MRAM device has a stack arrangement in which a tunnel barrier layer is formed over a magnetizable reference layer, a metal layer is formed over the tunnel barrier layer, a free layer of a magnetizable material is formed over the metal layer, and an oxide layer is formed over the free layer as a cap layer. The resulting MRAM device has a thin free layer that exhibits a low magnetic moment.

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Yorktown Heights, NY, United States of America

Guohan Hu