Magnetization Inclination for Fast Spin-Transfer Torque Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Spin implantation magnetization reversal elements using perpendicular magnetization films experience prolonged magnetization reversal times and decreased readout signal amplitudes, necessitating a solution for high-speed operation with reduced current consumption.
Innovation Solution
A memory apparatus with a layer structure including a memory layer, a magnetic fixed layer, and an intermediate non-magnetic layer, where a standby current is used to incline the magnetization direction from perpendicular, followed by a recording current to change it, optimizing magnetization reversal time and signal amplitude.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If a perpendicular magnetization film is used for spin implantation magnetization reversal, then the device size can be miniaturized, but the magnetization reversal time is prolonged
Solution Approach 1:
The patent applies preliminary action by inclining the magnetization direction from perpendicular to in-plane using a weak magnetic field or current before applying the main recording current. This preliminary inclination prepares the magnetization in a state that reduces the reversal time when the recording current is applied, thus resolving the contradiction between miniaturization and reversal speed.
Solution Approach 2:
The patent changes the magnetization direction parameter from strictly perpendicular to inclined (at a specific angle to the perpendicular direction). This parameter change allows the device to maintain miniaturization benefits while achieving faster magnetization reversal by optimizing the initial magnetization orientation before switching.
2Volume of moving object
If a perpendicular magnetization film is used for spin implantation magnetization reversal, then the device size can be miniaturized, but the readout signal amplitude decreases
Solution Approach 1:
The patent optimizes the magnetization direction parameter by inclining it at a specific angle relative to the perpendicular direction. This angular optimization simultaneously addresses both the reversal time and readout signal amplitude issues, allowing miniaturization while maintaining adequate signal strength for reliable readout.
3Duration of action of moving object
If standby current is applied to incline magnetization direction, then the magnetization reversal time is shortened, but the current consumption increases
Solution Approach 1:
The patent uses a weak current or magnetic field as a preliminary action to incline the magnetization direction before applying the main recording current. This preliminary step requires minimal energy compared to the alternative of applying a much stronger current to achieve the same reversal effect directly, thus reducing overall current consumption while achieving fast reversal.
Solution Approach 2:
The patent substitutes the direct application of high current (mechanical/electrical force) with a combination of weak current and magnetic field action. This substitution achieves the same magnetization reversal effect with lower energy consumption by utilizing the synergistic effect of multiple weaker influences rather than one strong influence.
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 configuration shortens magnetization reversal time, decreases current requirements, and maintains readout signal amplitude, enabling high-speed operation with reduced current consumption.
Implementation Method 1
a memory layer where a direction of magnetization is changed corresponding to information... current being capable of flowing in a lamination direction of the layer structure
Implementation Method 2
a method of reversing magnetization by directly implanting spin-polarized electrons into a recording layer
Data Source
Figure 1
Figure 2
Figure 3
AI summary
[Object] To provide a memory apparatus capable of operating at high speed with less current and inhibiting a decrease in an amplitude of a readout signal. [Solving Means] A memory apparatus includes a memory device having a layer structure at least including a memory layer where a direction of magnetization is changed corresponding to information, a magnetic fixed layer where the direction of the magnetization is fixed, and an intermediate layer made of a non-magnetic body disposed between the memory layer and the magnetic fixed layer; current being capable of flowing in a lamination direction of the layer structure; a wiring for supplying the memory device with current flowing to the lamination direction; and a memory control unit for storing information by flowing standby current at a predetermined level to the memory device via the wiring to incline the magnetization direction of the memory layer from the direction perpendicular to a film surface and flowing recording current that is higher than the standby current via the wiring to change the magnetization direction of the memory layer.