Voltage-Driven Magnetic Memory With Antiferromagnetic Bit Line
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional magnetic random access memory technologies face challenges with high power consumption and tunnel barrier breakdown when using spin transfer torque magnetization switching, and require techniques to enhance magnetization modulation with voltage writing methods.
Innovation Solution
A magnetic memory design incorporating a magnetoresistive device with a first and second magnetic layer, a nonmagnetic layer in between, and wiring with antiferromagnetic materials, utilizing a voltage writing method that applies voltage between the bit line and electrode to modulate magnetization without flowing current through the tunnel barrier, and employing high dielectric materials to increase magnetization state modulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If spin transfer torque magnetization switching is used to write data, then magnetization can be switched effectively, but power consumption increases and peripheral circuit area increases
Solution Approach 1:
The patent replaces the conventional current-based spin transfer torque method with a voltage-based magnetization switching method. By applying voltage to the magnetic storage layer through an insulating layer, the method substitutes electrical current injection with electric field-induced electron number modulation, thereby reducing power consumption while achieving magnetization switching.
Solution Approach 2:
The patent changes the fundamental writing parameter from current density to voltage. By controlling the number of electrons in the magnetic storage layer through voltage application, the system achieves magnetization switching without requiring high current density, thus reducing power consumption and peripheral circuit requirements.
2Use of energy by moving object
If voltage magnetization writing method is used, then power consumption is reduced, but tunnel barrier breakdown occurs and magnetization modulation efficiency is insufficient
Solution Approach 1:
The patent applies voltage locally to the magnetic storage layer through the insulating layer, creating a localized electric field that modulates electron number only in the vicinity of the interface. This localized approach prevents widespread tunnel barrier breakdown while achieving effective magnetization switching in the target region.
Solution Approach 2:
The insulating layer serves as an intermediary between the voltage source and the magnetic storage layer. It enables voltage application for magnetization control while preventing direct current flow that would cause tunnel barrier breakdown, thus protecting the barrier while achieving the desired magnetization modulation.
3Productivity
If voltage magnetization writing method is used, then degree of integration increases, but magnetization modulation efficiency with applied voltage is insufficient
Solution Approach 1:
The patent enhances magnetization modulation efficiency by changing the control parameter from direct magnetic field or current to voltage-induced electron number modulation. This parameter change enables more efficient coupling between the applied voltage and the magnetic state, improving modulation efficiency while maintaining high integration density.
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 approach reduces power consumption, suppresses tunnel barrier breakdown, and allows for higher integration density by controlling magnetization direction effectively without current limitations, enabling efficient and reliable magnetic memory operations.
Implementation Method 1
attempts have been actively performed for applying a magnetoresistive effect device utilizing a tunnel magnetoresistive effect to magnetic random access memory
Implementation Method 2
Writing to the magnetoresistive effect device is performed by a spin transfer torque magnetization switching method in general, and magnetization of a magnetic storage layer is switched by injecting spin-polarized electrons (spin injection current) into the magnetic storage layer
Implementation Method 3
In the voltage magnetization writing method, by applying a voltage to the magnetic storage layer of the magnetoresistive effect device via an insulating layer, the number of electrons is changed of the magnetic storage layer in the vicinity of an interface with the insulating layer, and a magnetization direction of the magnetic storage layer is changed
Data Source
AI summary
A magnetic memory according to an embodiment includes: a magnetoresistive device including a first magnetic layer, a second magnetic layer, and a first nonmagnetic layer between the first magnetic layer and the second magnetic layer; a first wiring electrically connected to the first magnetic layer; a second wiring that is electrically connected to the second magnetic layer and contains an antiferromagnetic material; a third wiring crossing the second wiring; an insulating layer between the second wiring and the third wiring; a first write circuit for applying a voltage between the second wiring and the third wiring; and a read circuit electrically connected to the first wiring and the second wiring.