H01F41/308

TMR Sensor with Magnetic Tunnel Junctions with a Free Layer Having an Intrinsic Anisotropy

Embodiments of the present disclosure generally relate to a large field range TMR sensor of magnetic tunnel junctions (MTJs) with a free layer having an intrinsic anisotropy. In one embodiment, a tunnel magnetoresistive (TMR) based magnetic sensor in a Wheatstone configuration includes at least one MTJ. The MTJ includes a free layer having an intrinsic anisotropy produced by deposition at a high oblique angle from normal. Magnetic domain formations within the free layer can be further controlled by a pinned layer canted at an angle to the intrinsic anisotropy of the free layer, by a hard bias element, by shape anisotropy, or combinations thereof.

Highly Physical Ion Resistive Spacer to Define Chemical Damage Free Sub 60nm MRAM Devices
20210217951 · 2021-07-15 ·

A magnetic tunneling junction (MTJ) structure comprises a pinned layer on a bottom electrode. a barrier layer on the pinned layer, wherein a second metal re-deposition layer is on sidewalls of the barrier layer and the pinned layer, a free layer on the barrier layer wherein the free layer has a first width smaller than a second width of the pinned layer, a top electrode on the free layer having a same first width as the free layer wherein a first metal re-deposition layer is on sidewalls of the free layer and top electrode, and dielectric spacers on sidewalls of the free layer and top electrode covering the first metal re-deposition layer wherein the free layer and the top electrode together with the dielectric spacers have a same the second width as the pinned layer wherein the dielectric spacers prevent shorting between the first and second metal re-deposition layers.

Method for manufacturing a magnetic memory element using Ru and diamond like carbon hard masks

A method for manufacturing a magnetic memory element array that includes the use of a Ru hard mask layer and a diamond like carbon hard mask layer formed over the Ru hard mask layer. A plurality of magnetic memory element layers are deposited over a wafer and a Ru hard mask layer is deposited over the plurality of memory element layers. A layer of diamond like carbon is deposited over the Ru hard mask layer, and a photoresist mask is formed over the layer of diamond like carbon. A reactive ion etching is then performed to transfer the image of the photoresist mask onto the diamond like carbon mask, and an ion milling is performed to transfer the image of the patterned diamond like carbon mask onto the underlying Ru hard mask and memory element layers. The diamond like carbon mask can then be removed by reactive ion etching.

SHORT CIRCUIT REDUCTION IN MAGNETIC TUNNEL JUNCTIONS

A spin-transfer torque magneto-resistive random access memory (STT-MRAM) device is provided. The STT-MRAM device includes a substrate, a dielectric layer and a magnetic tunnel junction (MTJ) stack. The substrate includes a conductor and a landing pad. The MTJ stack includes a reference layer element, a free layer assembly and a barrier layer element. The reference layer element is lined with redeposited metal and is disposed on the landing pad within the dielectric layer. The free layer assembly includes a free layer element, a hard mask layer element disposed on the free layer element, redeposited metal lining sidewalls of the free and hard mask layer elements and dielectric material lining the redeposited metal. The barrier layer element is interposed between and has a same width as the reference layer element and the free layer assembly.

Self-aligned encapsulation hard mask to separate physically under-etched MTJ cells to reduce conductive R-deposition

A method for etching a magnetic tunneling junction (MTJ) structure is described. A MTJ stack is deposited on a bottom electrode wherein the MTJ stack comprises at least a pinned layer, a barrier layer on the pinned layer, and a free layer on the barrier layer, A top electrode layer is deposited on the MTJ stack. A hard mask is deposited on the top electrode layer. The top electrode layer and hard mask are etched. Thereafter, the MTJ stack not covered by the hard mask is etched, stopping at or within the pinned layer. Thereafter, an encapsulation layer is deposited over the partially etched MTJ stack and etched away on horizontal surfaces leaving a self-aligned hard mask on sidewalls of the partially etched MTJ stack. Finally, the remaining MTJ stack not covered by hard mask and self-aligned hard mask is etched to complete the MTJ structure.

Sub 60nm etchless MRAM devices by ion beam etching fabricated T-shaped bottom electrode

A first conductive layer is patterned and trimmed to form a sub 30 nm conductive via on a first bottom electrode. The conductive via is encapsulated with a first dielectric layer and planarized to expose a top surface of the conductive via. A second conductive layer is deposited over the first dielectric layer and the conductive via. The second conductive layer is patterned to form a sub 60 nm second conductive layer wherein the conductive via and second conductive layer together form a T-shaped second bottom electrode. MTJ stacks are deposited on the T-shaped second bottom electrode and on the first bottom electrode wherein the MTJ stacks are discontinuous. A second dielectric layer is deposited over the MTJ stacks and planarized to expose a top surface of the MTJ stack on the T-shaped second bottom electrode. A top electrode contacts the MTJ stack on the T-shaped second bottom electrode plug.

Method for manufacturing reduced pitch magnetic random access memory pillar
10868236 · 2020-12-15 · ·

A method for forming self aligned magnetic memory element pillars for Magnetic Random Access Memory. The method allows the magnetic memory element pillars to be arranged in staggered rows of memory elements at a pitch that is smaller than what is possible using photolithography alone. The method involves forming a spacer mask in the form of an array of connected rings arranged in a square pattern of non-staggered rows. A sacrificial mask material is deposited over the spacer mask and the spacer mask is then removed, leaving sacrificial mask material in the holes at the center of the rings and also in the spaces between the rings. A reactive ion processes is then performed to transfer the pattern of the sacrificial mask onto underlying hard mask layers. A material removal process can then be performed to define a plurality of memory element pillars.

MRAM device formation with in-situ encapsulation

MRAM devices with in-situ encapsulation are provided. In one aspect, a method of forming an MRAM device includes: patterning an MRAM stack disposed on a dielectric into individual memory cell stacks, wherein the MRAM stack includes a bottom electrode, a MTJ, and a top electrode, and wherein the patterning is performed using an intermediate angle IBE landing on the dielectric; removing redeposited metal from the memory cell stacks using a high angle IBE; redepositing the dielectric along the sidewalls of the memory cell stacks using a low angle IBE to form a first layer of dielectric encapsulating the memory cell stacks; and depositing a second layer of dielectric, wherein the first/second layers of dielectric form a bilayer dielectric spacer structure, wherein the patterning, removing of the redeposited metal, and redepositing the dielectric steps are all performed in-situ. An MRAM device is also provided.

MRAM DEVICE FORMATION WITH IN-SITU ENCAPSULATION

MRAM devices with in-situ encapsulation are provided. In one aspect, a method of forming an MRAM device includes: patterning an MRAM stack disposed on a dielectric into individual memory cell stacks, wherein the MRAM stack includes a bottom electrode, a MTJ, and a top electrode, and wherein the patterning is performed using an intermediate angle IBE landing on the dielectric; removing redeposited metal from the memory cell stacks using a high angle IBE; redepositing the dielectric along the sidewalls of the memory cell stacks using a low angle IBE to form a first layer of dielectric encapsulating the memory cell stacks; and depositing a second layer of dielectric, wherein the first/second layers of dielectric form a bilayer dielectric spacer structure, wherein the patterning, removing of the redeposited metal, and redepositing the dielectric steps are all performed in-situ. An MRAM device is also provided.

Large Height Tree-Like Sub 30nm Vias to Reduce Conductive Material Re-Deposition for Sub 60nm MRAM Devices
20200343443 · 2020-10-29 ·

A stack of connecting metal vias is formed on a bottom electrode by repeating steps of depositing a conductive via layer, patterning and trimming the conductive via layer to form a sub 30 nm conductive via, encapsulating the conductive via with a dielectric layer, and exposing a top surface of the conductive via. A MTJ stack is deposited on the encapsulated via stack. A top electrode layer is deposited on the MTJ stack and patterned and trimmed to form a sub 60 nm hard mask. The MTJ stack is etched using the hard mask to form an MTJ device and over etched into the encapsulation layers but not into the bottom electrode wherein metal re-deposition material is formed on sidewalls of the encapsulation layers underlying the MTJ device and not on sidewalls of a barrier layer of the MTJ device.