Multipole Micro-Magnet Arrays via Coercivity Diffusion Patterning

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for fabricating multipole arrays of hard micro-magnets require access to the magnetic layer surface, making it difficult to integrate them into devices with buried components or after packaging.

Innovation Solution

A method involving the deposition of a coercivity changing element according to a pattern on a first material, followed by diffusion to form a magnetic layer with areas of different coercivity values, allowing for global and local magnetization without surface access.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If thermo-magnetic patterning or magnetic field patterning is used to fabricate multipole arrays, then multipole arrays of hard micro-magnets can be produced, but access to the magnetic layer surface is required which prevents integration after packaging or with buried components

Engineering Contradiction:

Improvemultipole array fabricationVSAvoidintegration flexibility

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The magnetic layer is deposited and patterned with different coercivity regions before other components are added and before final packaging. This preliminary patterning allows the magnetic structure to be created when access is available, and then the device can be completed with burried components and packaging without requiring subsequent access to the magnetic layer.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Instead of requiring lateral access to the magnetic layer surface for patterning, the invention uses vertical diffusion through a deposited layer. The coercivity is modified by diffusing elements through the thickness of the magnetic layer, transforming the problem from a lateral access requirement to a vertical processing approach that can be performed through existing structures.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Manufacturing precision

If conventional fabrication methods requiring surface access are used, then multipole arrays can be fabricated, but the process becomes very constraining when integrating hard micro-magnets into devices

Engineering Contradiction:

Improvemultipole array patterningVSAvoidintegration process complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The invention combines the magnetic layer deposition with the coercivity patterning process. By depositing a uniform magnetic layer and then selectively modifying its coercivity through element diffusion, two steps (deposition and patterning) are effectively merged into a integrated process that reduces overall device complexity and eliminates the need for separate surface access operations.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The invention replaces mechanical surface access methods (such as lithography and etching that require lateral access) with a diffusion-based chemical process. Instead of mechanically removing or patterning material from the surface, the coercivity is modified through controlled diffusion of alloying elements, substituting a chemical process for mechanical surface manipulation.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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

Enables the fabrication of multipole arrays of hard micro-magnets that can be integrated into devices even after packaging, with remagnetizable and reconfigurable properties.

Implementation Method 1

a step of diffusion of the coercivity changing element into certain regions to form a magnetic layer having first areas made of the first material and second areas having a second coercivity

Methodology Applied

Scientific EffectDiffusion: Diffusion

Implementation Method 2

the step of diffusion is achieved by heating

Methodology Applied

Scientific EffectHeating: Heating

Data Source

PatentEP4542589A1Method for fabricating an array of magnets and associated method for configuring and array of magnets

Publication Date: 2025.04.23 CENT NAT DE LA RECH SCI (C N R S)

Figure 1
Figure 2

AI summary

The invention concerns a method for fabricating an array of magnets (10), the method comprising: - a step of deposition of a coercivity changing element according to a pattern on a first material having a first coercivity value, the coercivity changing element being adapted to change the coercivity of the first material, and - a step of diffusion of the coercivity changing element into certain regions to form a magnetic layer (16) having first areas (A1) made of the first material and second areas (A2) having a second coercivity, made of a second material comprising the first material and the coercivity changing element.