CoFe Magnetic Memory Element With Oxygen Interface
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Magnetic Random Access Memory (MRAM) faces challenges in increasing capacity and reducing chip size while maintaining a stable thermal disturbance constant, which is crucial for long-term information retention, especially when the size of the Magnetic Tunnel Junction (MTJ) element is minimized.
Innovation Solution
The magnetic memory element incorporates a memory layer with perpendicular magnetic anisotropy, a reference layer with fixed magnetization, and a tunnel barrier layer with oxygen atoms at the interface, using an alloy of cobalt and iron, to enhance magnetic anisotropy energy and thermal stability, allowing for variable magnetization and stable information retention.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If the size of the MTJ element is minimized to increase memory capacity and reduce chip size, then memory density is improved, but the thermal disturbance constant becomes insufficient leading to unstable information retention
Solution Approach 1:
The patent applies local quality by creating perpendicular magnetic anisotropy at specific interfaces (tunnel barrier layer/memory layer interfaces) rather than uniformly throughout the structure. Oxygen atoms are selectively positioned at these interfaces to generate localized magnetic anisotropy, allowing the magnetic properties to be optimized locally while maintaining overall device miniaturization.
Solution Approach 2:
The patent employs composite materials by combining cobalt and iron to form a CoFe alloy in the memory layer. This composite material structure provides both the necessary magnetic properties and enables the generation of perpendicular magnetic anisotropy when interfaced with the tunnel barrier layer, resolving the contradiction between size reduction and thermal stability.
2Productivity
If the size of the MTJ element is reduced to increase memory capacity, then productivity is improved, but the magnetic anisotropy energy becomes insufficient leading to poor thermal stability
Solution Approach 1:
The patent transitions from in-plane magnetization to perpendicular magnetization by changing the dimension of magnetic anisotropy. The tunnel barrier layer/memory layer interface structure generates magnetic anisotropy in the perpendicular direction (out-of-plane), which provides stronger thermal stability even for minimized element sizes, thus enabling high memory capacity while maintaining sufficient magnetic anisotropy energy.
Solution Approach 2:
The patent changes the magnetic anisotropy parameter from in-plane to perpendicular orientation through the introduction of oxygen atoms at the tunnel barrier layer/memory layer interfaces. This parameter change fundamentally alters the magnetic energy landscape, providing sufficient magnetic anisotropy energy even when the MTJ element size is minimized for high productivity.
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 ensures a sufficient thermal disturbance constant, enabling the MTJ element to stably retain information for a long period even when minimized, by increasing perpendicular magnetic anisotropy energy and maintaining reliable data storage.
Implementation Method 1
a memory layer which includes magnetic anisotropy on a film surface in a perpendicular direction
Implementation Method 2
A Magnetic Random Access Memory (MRAM) includes a Magnetic Tunnel Junction (MTJ) element which according to a magneto-resistive effect has a resistance value that is variable due to magnetized states
Data Source
AI summary
A magnetic memory element includes a memory layer having magnetic anisotropy on the film surface thereof in the perpendicular direction and in which the magnetization direction is variable, a reference layer having magnetic anisotropy on the film surface thereof in the perpendicular direction and in which the magnetization direction is not variable, and a tunnel barrier layer which is interposed between the memory layer and the reference layer. The memory layer is made of an alloy including cobalt (Co) andiron (Fe). A plurality of oxygen atoms are present on both interfaces of the memory layer.