Spin-Orbit-Torque Element Heat Sink Layer Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Magnetization reversal in spin-orbit-torque magnetoresistance effect elements requires high current densities, leading to issues like Joule heat-induced dissolution and electromigration in the spin-orbit torque wiring, which affects the longevity of these elements.
Innovation Solution
Incorporating a heat sink layer that overlaps with the spin-orbit torque wiring and is positioned within a specific distance to effectively dissipate heat generated, reducing the need for high current densities and mitigating heat trapping.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high current density is applied to achieve magnetization reversal, then magnetization reversal is achieved, but Joule heat-induced dissolution and electromigration occur in the spin-orbit torque wiring
Solution Approach 1:
A heat sink layer is introduced as an intermediary component between the spin-orbit torque wiring and the substrate. This heat sink layer acts as a thermal mediator that captures and dissipates Joule heat generated during magnetization reversal, preventing direct thermal damage to the spin-orbit torque wiring and reducing electromigration effects.
Solution Approach 2:
The harmful thermal energy is extracted from the spin-orbit torque wiring system by introducing a dedicated heat sink layer. This layer selectively absorbs and removes the Joule heat that would otherwise cause dissolution and electromigration, separating the thermal management function from the magnetization reversal function.
2Temperature
If the spin-orbit torque wiring is made thin to reduce heat trapping, then heat trapping is reduced, but the wiring becomes more susceptible to dissolution and electromigration
Solution Approach 1:
The heat sink layer serves as a protective intermediary that enables the use of thin spin-orbit torque wiring. By providing an external thermal management solution, the wiring can be made thinner for better heat dissipation without compromising durability, as the heat sink layer compensates for the reduced thermal mass of the thin wiring.
Solution Approach 2:
Instead of managing heat within the平面 dimensions of the spin-orbit torque wiring, the solution extends thermal management to a vertical dimension by introducing a heat sink layer beneath the wiring. This dimensional transition allows heat to be dissipated through a separate thermal pathway without requiring the wiring itself to be thick.
3Temperature
If a heat sink layer is added to improve heat dissipation, then heat dissipation is improved, but device complexity increases
Solution Approach 1:
The heat sink layer is designed to perform multiple functions: it serves as a thermal management component for heat dissipation, a structural support layer for the thin spin-orbit torque wiring, and potentially a protective barrier against substrate-related thermal issues. This multi-functionality justifies the added structural element.
Solution Approach 2:
The heat sink layer is designed with specific parameter optimizations: it is positioned at a controlled distance from the spin-orbit torque wiring (not too close to interfere with magnetization reversal, not too far to be ineffective), and its material composition is selected for optimal thermal conductivity. These parameter optimizations ensure effective heat dissipation while minimizing unnecessary complexity.
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
The implementation of a heat sink layer improves heat dissipation in spin-orbit torque magnetoresistance effect elements, enhancing their durability and performance by reducing the risk of Joule heat-induced damage and electromigration.
Implementation Method 1
when a current flows in the SOT wiring, Joule heat is generated
Implementation Method 2
a heat sink layer which extends in a first direction, is disposed so that the heat sink layer and the spin-orbit torque wiring at least partially overlap when viewed in a plan view from the lamination direction, and is provided spaced from the spin-orbit torque wiring in the lamination direction by a distance of twice a thickness of the functional unit or less
Implementation Method 3
magnetization reversal using a pure spin current generated due a spin Hall effect which is a mechanism different from an STT and serves as a means for reducing an inversion current
Implementation Method 4
A pure spin current generated due to a spin Hall effect induces a spin-orbit torque (SOT) and magnetization reversal occurs due to the SOT
Data Source
AI summary
A spin-orbit-torque magnetoresistance effect element of the present invention includes: a functional unit, a first ferromagnetic layer whose magnetization direction is configured to be fixed, a second ferromagnetic layer whose magnetization direction is configured to change, and a non-magnetic layer located between the first ferromagnetic layer and the second ferromagnetic layer being laminated therein; a spin-orbit torque wiring which extends in a first direction which intersects a lamination direction of the functional unit and is joined to the second ferromagnetic layer; a heat sink layer which extends in the first direction, is disposed so that the heat sink layer and the spin-orbit torque wiring at least partially overlap when viewed in a plan view from the lamination direction, and is provided spaced from the spin-orbit torque wiring in the lamination direction by a distance of twice a thickness of the functional unit or less in the lamination direction thereof.