MRAM Seed Layer Shunting for Low-Resistance MTJ Structures
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional MRAM structures face increased resistance and tunnel magnetoresistance (TMR) penalties due to the use of thick tunnel barrier seed layers, which adversely affect magnetic properties and scalability.
Innovation Solution
A memory structure with a seeding area featuring a tunnel barrier seed layer beneath a chemical templating layer, where redeposited metallic material shunts the sidewalls to reduce resistance with minimal TMR loss, incorporating a non-magnetic pedestal structure and a MTJ structure with intentional shunting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a thick tunnel barrier seed layer is used, then deposition control is improved, but resistance increases and TMR performance deteriorates
Solution Approach 1:
The patent divides the tunnel barrier structure into two distinct segments: a thick seed layer (5-10 nm) for deposition control and a thin functional barrier layer (1-2 nm) for low resistance and high TMR performance. This segmentation allows each layer to optimize its thickness for its specific function, resolving the contradiction between deposition control and TMR performance.
Solution Approach 2:
The patent introduces a chemical templating layer as an intermediary between the thick seed layer and the thin functional barrier layer. This intermediate layer facilitates the transition from the thick seed structure to the thin functional barrier, enabling both deposition control from the thick layer and low resistance/high TMR from the thin layer.
2Manufacturing precision
If a thick tunnel barrier seed layer is used, then deposition control is improved, but device scalability is reduced
Solution Approach 1:
By segmenting the barrier structure into thick seed and thin functional layers, the patent enables scalable device fabrication. The thin functional layer (1-2 nm) allows for smaller device dimensions and higher density, while the thick seed layer remains optimized for deposition control during manufacturing.
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 solution achieves reduced resistance and minimal TMR penalty, enhancing the performance and scalability of MRAM structures by optimizing magnetic and crystallographic order while maintaining effective data storage.
Implementation Method 1
Redeposited metallic material is located on at least a sidewall of the tunnel barrier seed layer of the seeding area so as to shunt that area of the structure
Implementation Method 2
growing magnetic stacks on top of a relatively thick tunnel barrier seed layer is desired for better deposition control; a thin tunnel barrier seed layer results in magnetic or crystallographic disordering resulting in adverse magnetic properties
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
A memory structure, i.e., magnetoresistive random access memory (MRAM) structure, is provided that includes a seeding area including at least a tunnel barrier seed layer (22) located beneath a chemical templating layer (24b, 24u) that is wider than the magnetic tunnel junction (MTJ) structure (26, 28, 30) that is located on the chemical templating layer. Redeposited metallic material (36) is located on at least a sidewall of the tunnel barrier seed layer of the seeding area so as to shunt that area of the structure. The memory structure has reduced resistance with minimal tunnel magnetoresistance (TMR) loss penalty.