Composite Magnetic Sealing Material for Electronic Circuit Packages

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional composite magnetic sealing materials for electronic circuit packages have high thermal expansion coefficients, leading to warping and interfacial delamination issues due to mismatches with substrate and components, which conventional noise countermeasures fail to address effectively.

Innovation Solution

A composite magnetic sealing material with a blend ratio of 50 vol. % to 85 vol. % of a first magnetic filler containing Ni and Fe, and a second magnetic filler with a different grain size distribution, along with a non-magnetic filler, to achieve a low thermal expansion coefficient and high magnetic shielding characteristics, while ensuring insulating performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If conventional composite magnetic sealing materials are used to achieve magnetic shielding characteristics, then magnetic shielding performance is improved, but thermal expansion coefficient becomes too large causing warping and delamination

Engineering Contradiction:

Improvemagnetic shielding performanceVSAvoidwarping and delamination due to thermal expansion mismatch

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent changes the particle size distribution parameter of magnetic fillers by introducing a specific D10 value (0.5μm to 5μm) alongside the D50 value. This parameter modification enables the composite material to achieve both high magnetic shielding performance and low thermal expansion coefficient, preventing warping and delamination while maintaining shielding effectiveness

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite magnetic sealing material combining magnetic fillers with specific particle size distribution (D50: 5μm to 20μm, D10: 0.5μm to 5μm) and resin materials. This composite structure achieves both high magnetic shielding characteristics and controlled thermal expansion properties, resolving the contradiction between shielding performance and dimensional stability

Inventive Principle:

Principle #40Composite materials

2Reliability

If the thermal expansion coefficient of magnetic sealing material is reduced to match substrate and components, then warping and delamination are prevented, but magnetic shielding characteristics may be compromised

Engineering Contradiction:

Improvethermal expansion matching to prevent warpingVSAvoidmagnetic shielding effectiveness

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent modifies the particle size distribution parameters (D50 and D10 values) of magnetic fillers to optimize both thermal expansion coefficient and magnetic shielding characteristics. By controlling D10 to be 0.5μm to 5μm while maintaining D50 at 5μm to 20μm, the material achieves low thermal expansion for warp prevention while preserving high magnetic shielding effectiveness

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent applies different particle size characteristics to different aspects of material performance: larger particles (D50 range) contribute to structural stability and thermal expansion control, while smaller particles (D10 range) enhance magnetic shielding properties. This local quality differentiation allows simultaneous achievement of both goals

Inventive Principle:

Principle #3Local quality

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 effectively reduces thermal expansion mismatch, prevents warping and delamination, and maintains high magnetic shielding effectiveness, enhancing the reliability and performance of electronic circuit packages.

Implementation Method 1

a composite magnetic sealing material added with soft magnetic powder having an oxide film as a molding material for electronic circuit package

Methodology Applied

Scientific EffectMagnetic shielding: Magnetism

Implementation Method 2

a first magnetic filler containing a 32 wt. % to 39 wt. % of metal material composed mainly of Ni in Fe

Methodology Applied

Scientific EffectFerromagnetism: Ferromagnetism

Implementation Method 3

conventional composite magnetic sealing materials have a drawback in that it has a large thermal expansion coefficient

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentUS10269727B2Composite magnetic sealing material and electronic circuit package using the same as mold material

Publication Date: 2019.04.23 TDK CORP

AI summary

Disclosed herein is a composite magnetic sealing material includes a resin material and a filler blended in the resin material in a blend ratio of 50 vol. % or more and 85 vol. % or less. The filler includes a first magnetic filler containing Fe and 32 wt. % or more and 39 wt. % or less of a metal material composed mainly of Ni, the first magnetic filler having a first grain size distribution, and a second magnetic filler having a second grain size distribution different from the first grain size distribution.