Magnetic-Dielectric Composite for High-Frequency Antenna Substrates
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Solution Overview
Problem
Existing metal-based soft magnetic materials suffer from high eddy current loss at high frequencies, leading to decreased permeability in GHz regions, limiting their use in high-frequency applications due to low electric resistance and separation issues with insulating dielectric materials.
Innovation Solution
A magnetic-dielectric composite is created by embedding spaced soft magnetic material nanowires, such as Fe7Co3, within a porous insulating dielectric substrate, utilizing anodization and electrodeposition to control permittivity and minimize eddy current loss, with the substrate acting as both a dielectric and insulating material.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If metal-based soft magnetic materials are used to maintain permeability, then magnetic properties are improved, but eddy current loss increases due to low electric resistance
Solution Approach 1:
The soft magnetic material is segmented into nanowire form with diameter of 10-500 nm, separating the material into electrically isolated segments that prevent eddy current formation while maintaining magnetic properties. The nanowires are spaced apart and surrounded by insulating dielectric substrate to ensure electrical isolation.
Solution Approach 2:
The invention uses a porous insulating dielectric substrate with pores filled by soft magnetic material nanowires. The porous structure provides both mechanical support and electrical insulation, allowing the magnetic nanowires to maintain permeability while the dielectric material prevents eddy current loss through its high electric resistance.
2Loss of energy
If ferrite-based materials are used to reduce eddy current loss, then electric resistance is improved, but saturation magnetization decreases requiring larger volume
Solution Approach 1:
The invention creates a composite material system combining soft magnetic material nanowires (providing high saturation magnetization) with insulating dielectric substrate material (providing high electric resistance). This composite structure achieves both low eddy current loss and high saturation magnetization by combining the advantages of both materials without their individual limitations.
3Temperature
If metal-based soft magnetic materials are used for high permeability, then magnetic properties are improved, but separation from insulating dielectric materials occurs
Solution Approach 1:
The soft magnetic material nanowires are nested within the pores of the insulating dielectric substrate, with the nanowires surrounded by the dielectric material. This nested structure ensures intimate contact and strong adhesion between the magnetic and dielectric components, preventing separation while maintaining the electrical insulation necessary for high-frequency operation.
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 composite achieves stable high permeability and permittivity across 0.1 to 5 GHz, enabling smaller mobile devices with improved data communication quality and frequency stability by minimizing eddy current loss and maintaining permeability in high-frequency bands.
Implementation Method 1
the substrate for use in a mobile phone operating in a high frequency band is used in various cases... a high permittivity and high permeability substrate
Implementation Method 2
a ferrite (MFe2O4)-based material having high electric resistance in a high frequency region is usually used... the soft magnetic material basically needs to have excellent permeability and saturation magnetization, high electric resistance and low coercive force characteristics and low eddy current loss characteristics are required
Implementation Method 3
a nanoporous alumina membrane obtained by a two-step anodization process in which a 99.998% pure aluminum plate is, i.a., anodized in 0.3-M oxalic acid (C 2 H 2 O 4 ) at 40 V for 4 hours to produce pores having a diameter of 40 nm
Implementation Method 4
NiFe ferromagnetic nanowires are deposited from a solution of 0.084-M NiCl 2 ·6H 2 O, 0.476-M NiSO 4 ·6H 2 O, 0.029-M FeSO 4 ·6H 2 O, 0.65-M H 3 BO 3 , 0.019-M sodium saccharin, and 0.0004-M sodium dodecyl-sulfate at pH = 3.4 and using a 100mA/cm2 current density
Data Source
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AI summary
The present invention relates to a magnetic-dielectric composite for a high-frequency antenna substrate, and a manufacturing method therefor, the composite comprising: a porous insulating dielectric substrate including an upper surface, a lower surface and lateral surfaces, and having a plurality of pores penetrating the upper surface and the lower surface; and soft ferrite nano-wires provided within the pores, wherein the soft ferrite nano-wires are encompassed by the insulating dielectric substrate so as to be separated from each other. The present invention controls a dielectric constant and can minimize eddy current loss by having a structure in which the soft ferrite nano-wires are provided within the pores of the insulating dielectric substrate and in which the soft ferrite nano-wires are encompassed by the insulating dielectric substrate so as to be separated from each other.