Magnetoresistive Element Tapered Shift Control Layer Stray Field Suppression

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Magnetoresistive effect elements face challenges in maintaining stable magnetization orientation due to stray magnetic fields generated by the reference and shift control layers, leading to failures in magnetization reversal and data storage in memory devices.

Innovation Solution

The magnetoresistive effect element is designed with a specific shape for the shift control layer and reference layer, where the shift control layer has a smaller top area and larger bottom area, and the angle between the top and side of the shift control layer is greater than that of the reference layer, effectively suppressing stray magnetic fields and stabilizing magnetization orientations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the reference layer and shift control layer are designed with conventional shapes, then the magnetoresistive effect element can be manufactured with standard processes, but stray magnetic fields are generated that destabilize magnetization orientation

Engineering Contradiction:

Improvemagnetization orientation stabilityVSAvoidstray magnetic fields

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The shift control layer is designed with an asymmetric shape where the top area is smaller than the bottom area, creating a tapered structure. This asymmetric geometry modifies the magnetic field distribution to reduce stray fields that destabilize magnetization orientation in the storage layer.

Inventive Principle:

Principle #4Asymmetry

Solution Approach 2:

The invention transitions from a conventional two-dimensional planar shape to a three-dimensional tapered structure by varying the area of the shift control layer from top to bottom. This dimensional change allows for optimized magnetic field control that cannot be achieved with flat, uniform shapes.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Reliability

If the shift control layer has a smaller top area and larger bottom area with greater angles, then stray magnetic fields are suppressed and magnetization is stabilized, but the manufacturing precision requirements increase

Engineering Contradiction:

Improvemagnetization reversal stabilityVSAvoidlayer shape control precision

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The invention specifies particular parameter ranges for the shift control layer geometry, including angle thresholds (greater than reference layer angles) and area relationships (top area smaller than bottom area). These parameter definitions provide clear manufacturing targets while achieving the desired magnetic field suppression.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If the magnetoresistive effect element uses standard layer configurations, then the device complexity is low, but the magnetic field strength required for magnetization reversal is insufficient leading to data storage failures

Engineering Contradiction:

Improvedata storage reliabilityVSAvoidmagnetic field strength for magnetization reversal

Core Design Contradiction:

ReliabilityVSForce

Solution Approach 1:

The shift control layer acts as an intermediary magnetic layer between the reference layer and storage layer. By controlling its shape and magnetization, it mediates the magnetic field distribution to enhance the effective field strength acting on the storage layer, improving magnetization reversal reliability.

Inventive Principle:

Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This design enhances the magnetic field strength required for magnetization reversal, reduces failures in data storage, and improves the reliability of magnetoresistive random access memory (MRAM) by controlling stray magnetic fields and optimizing the distribution of magnetic flux density.

Implementation Method 1

stray magnetic fields generated by the reference and shift control layers

Methodology Applied

Scientific EffectStray magnetic field: Magnetic Field

Implementation Method 2

Magnetoresistive effect elements which exhibit a resistance switchable based on the state thereof

Methodology Applied

Scientific EffectMagnetoresistive effect: Magnetoresistance

Data Source

PatentUS10230042B2Magnetoresistive element and method of manufacturing the same

Publication Date: 2019.03.12 KIOXIA CORP

AI summary

A magnetoresistive effect element according to one embodiment includes: a first magnetic layer; a nonmagnetic layer; a second magnetic layer; a metal layer; and a third magnetic layer. An area of a bottom of the third magnetic layer is larger than an area of a top of the third magnetic layer. An angle between the top of the third magnetic layer and a side of the third magnetic layer is larger than an angle between a top of the second magnetic layer and a side of the second magnetic layer, or an angle between the bottom of the third magnetic layer and a side of the third magnetic layer is smaller than an angle between the bottom of the second magnetic layer and a side of the second magnetic layer.