Nitrided Magnetoresistive Stack for Low-Energy Magnetization Reversal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current magneto resistive elements require significant energy for magnetization reversal, which is inefficient and not effectively addressed by existing technologies.
Innovation Solution
A magneto resistive element design featuring a laminate structure with specific nitride and non-nitride regions in ferromagnetic layers and a non-magnetic layer, where the nitride regions are closer to the insulating layer, reducing the energy required for magnetization reversal by lowering saturation magnetization and coercive force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If conventional magneto resistive element structure is used, then magnetization reversal can be achieved, but high energy consumption is required
Solution Approach 1:
The patent applies local quality by creating distinct nitride and non-nitride regions within the ferromagnetic layer. The nitride region (containing nitrogen) is positioned closer to the insulating layer and has lower saturation magnetization, while the non-nitride region has higher saturation magnetization. This spatial differentiation of material properties allows the element to reduce overall energy consumption for magnetization reversal while the non-nitride region maintains magnetization stability.
Solution Approach 2:
The patent employs composite materials by combining ferromagnetic material with nitrogen-containing regions and nitrogen-free regions in a single layer. This composite structure leverages the different magnetic properties of nitrided and non-nitrided portions to achieve both low energy consumption (from the nitride region) and high stability (from the non-nitride region), resolving the contradiction between energy efficiency and reliability.
2Reliability
If high current density is applied for magnetization reversal, then magnetization reversal is achieved, but excessive energy consumption and heating occur
Solution Approach 1:
By positioning the nitride region with lower saturation magnetization closer to the insulating layer, the patent reduces the current density threshold for magnetization reversal. This local modification allows magnetization switching at lower current densities, thereby reducing both energy consumption and heat generation while maintaining reliable magnetization reversal capability.
3Ease of manufacture
If uniform ferromagnetic layer is used, then manufacturing is simple, but magnetization reversal requires high energy
Solution Approach 1:
The patent introduces local quality variations (nitride and non-nitride regions) within the ferromagnetic layer to reduce energy for magnetization reversal. Despite this structural complexity, the manufacturing process remains relatively simple by using sequential sputtering with nitrogen atmosphere control, thus achieving a balance between manufacturing ease and energy efficiency.
Solution Approach 2:
The patent changes the nitrogen concentration parameter within the ferromagnetic layer to create regions with different magnetic properties. By controlling the nitrogen atmosphere during sputtering, the patent achieves the desired nitride/non-nitride region distribution, reducing magnetization reversal energy while maintaining manufacturing feasibility through parameter control rather than complex processing.
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 design enables magnetization reversal with lower energy consumption and increased MR ratio, reducing current density and unnecessary bias magnetic fields, while maintaining magnetization stability.
Implementation Method 1
The first ferromagnetic layer has a first non-nitride region and a first nitride region. The first nitride region is closer to the insulating layer than the first non-nitride region. The first nitride region contains nitrogen.
Implementation Method 2
A magneto resistive element in which a conductor is used for a non-magnetic layer is called a giant magneto resistive (GMR) element
Implementation Method 3
a magneto resistive element in which an insulating layer (a tunnel barrier layer or a barrier layer) is used for a non-magnetic layer is called a tunnel magneto resistive (TMR) element
Implementation Method 4
Patent Document 3 describes a method of controlling a direction of magnetization using spin transfer torque (STT) generated by flowing a current through a magneto resistive element in the lamination direction. This method is called a spin injection magnetization reversal method.
Data Source
AI summary
A magneto resistive element includes a laminate including a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic layer and an insulating layer configured to cover at least a part of a side surface of the laminate and including an insulator. The first ferromagnetic layer has a first non-nitride region and a first nitride region that is closer to the insulating layer than the first non-nitride region and contains nitrogen.