Glass Substrate Coil Circuit Board With EMI Shielding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional LC filters are large and difficult to integrate into small communication devices, and substrates like glass epoxy and LTCC technology face issues with rough surfaces and electromagnetic interference shielding.
Innovation Solution
A circuit board design featuring a glass substrate with coil wiring patterns on both surfaces, through holes for electrical connection, and an electromagnetic shielding layer made of conductive material to shield against electromagnetic waves, allowing for compact and high-capacity communication devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If conventional LC filters are used, then frequency filtering function is achieved, but the size becomes large and cannot be integrated into small communication devices
Solution Approach 1:
The patent transitions from planar coil patterns to three-dimensional coil structures formed through through-holes in the substrate. This vertical dimensionality change enables compact filter design that fits within small communication device housings while maintaining filtering performance
Solution Approach 2:
The coil structure is nested within the substrate by forming through-holes that pass completely through the substrate thickness. The coil pattern is embedded inside the substrate volume rather than occupying surface area, achieving space-efficient integration
2Ease of manufacture
If glass epoxy substrate with drilled through-holes is used, then coil structure is formed, but the inner peripheral wall becomes rough due to exposed glass fibers
Solution Approach 1:
The patent changes the substrate material from glass epoxy to glass ceramic, fundamentally altering the material properties. Glass ceramic provides a inherently smooth surface without exposed fibers, eliminating the roughness problem while maintaining manufacturability of through-holes
Solution Approach 2:
The use of glass ceramic as a composite material combines the benefits of ease of through-hole formation with inherent surface smoothness, resolving the contradiction between manufacturability and surface quality
3Ease of manufacture
If glass epoxy substrate is used, then coil pattern can be formed, but electrical characteristics deteriorate due to local variations in wiring width and diameter caused by rough surface
Solution Approach 1:
Changing the substrate material to glass ceramic fundamentally improves the surface parameters, providing uniform smoothness that ensures consistent wiring dimensions and reliable electrical characteristics throughout the coil structure
4Reliability
If LTCC technology with multilayer ceramic wiring is used, then coil is formed, but the thickness direction becomes large and cannot accommodate slim device housings
Solution Approach 1:
The patent uses through-holes that extend vertically through the substrate to create the coil structure in the thickness direction, rather than using multilayer horizontal stacking. This approach maintains thin profile while achieving three-dimensional coil geometry
Solution Approach 2:
The coil is segmented into multiple sections formed in different through-holes, with each section contributing to the overall inductance. This segmentation allows the coil to be distributed through the substrate thickness without requiring excessive total thickness
5Ease of manufacture
If conventional substrates are used, then coil structure is formed, but electromagnetic shielding against noise and interference is difficult to provide
Solution Approach 1:
The glass ceramic substrate serves multiple functions: it provides the structural base, enables through-hole coil formation, ensures surface smoothness for electrical performance, and offers inherent electromagnetic shielding properties. This multi-functionality resolves the contradiction between ease of manufacture and EMI protection
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 provides compact circuit boards with excellent electromagnetic shielding properties, suitable for small-size, high-speed communication devices, improving electrical characteristics and accommodating slim device housings.
Implementation Method 1
a through hole inner conductive surface formed on the inner side of the through hole, the through hole inner conductive surface enabling electrical connection between the end of the first coil wiring pattern and the end of the second coil wiring pattern
Implementation Method 2
an electromagnetic shielding layer comprised of conductive material, the electromagnetic shielding layer shielding against electromagnetic waves generated by the at least one coil
Data Source
AI summary
A circuit board includes a glass substrate having a first surface and a second surface facing away from the first surface; a first coil wiring pattern formed on the first surface and a second coil wiring pattern formed on the second surface, the first and second coil wiring patterns constituting part of a coil; a through hole extending through a predetermined portion of the glass substrate from an end of the first coil wiring pattern to an end of the second coil wiring pattern; a through hole inner conductive surface formed on the inner side of the through hole, the first and second coil wiring patterns and the through hole inner conductive surface constituting the coil wound around a direction perpendicular to an axis of the through hole and to a direction in which the first and second coil wiring patterns extend.