MRAM Storage Element Current Segmentation for Junction Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
MRAM devices are prone to damage and degradation due to excessive write current, affecting their performance and reliability, and existing solutions either compromise storage density or access speed.
Innovation Solution
A memory system that uses a combination of first and second currents to control the storage state of a storage element, where the second current flows through a source line without flowing through the storage element, reducing the risk of damage and enabling higher integration density and faster access speeds.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional MRAM write operations use high current through the storage element, then the storage state can be changed, but the magnetic tunnel junction becomes damaged or degraded
Solution Approach 1:
The write current path is segmented into two separate paths: one through the storage element (first current) and another through the source line (second current). This segmentation allows the total write current to be distributed, reducing the current burden on the magnetic tunnel junction while maintaining effective write capability.
Solution Approach 2:
The source line acts as an intermediary element that carries part of the write current (second current) without requiring it to pass through the storage element. This intermediary path enables current to be diverted away from the vulnerable magnetic tunnel junction, protecting it from excessive current damage.
2Ease of manufacture
If the memory structure is simplified to reduce complexity, then manufacturing becomes easier, but memory integration density decreases
Solution Approach 1:
The source line serves multiple functions: it acts as a current path for write operations (carrying second current), provides a reference potential for read operations, and enables the segmented current path mechanism. This multi-functionality reduces the need for additional dedicated structures, maintaining manufacturing simplicity while achieving higher integration density through the innovative current path configuration.
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 prevents degradation caused by excessive current, ensuring long-term reliability and enabling higher memory integration density and faster access speeds while maintaining the non-volatile and fast access characteristics of MRAM.
Implementation Method 1
a resistance between the source line and the bit line changes according to a relative direction between a magnetization direction of the free layer and a magnetization direction of the fixed layer
Implementation Method 2
a spin torque transfer layer, disposed between the free layer and the tunnel barrier layer; the spin torque transfer layer is configured to change the magnetization direction of the free layer
Data Source
AI summary
A memory and a read and write method of memory can prevent the magnetic random-access memory (MRAM) from being easily damaged or degraded by excessive write current during use, and increase memory integration density. The memory includes: a storage unit, comprising a storage element; a source line, electrically connected to a first end of the storage element; the memory is configured to change a storage state of the storage element by a first current and a second current, the first current flowing through the storage element and the second current flowing through the source line without flowing through the storage element.