David Dewey | Fujikura Kasei: Does a thicker coating always guarantee better electromagnetic shielding, or are you wasting material?
00:15:53 - 00:17:16
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Summary of the clip:
Does a thicker coating always guarantee better electromagnetic shielding, or are you wasting material?
The relationship between dry film thickness (DFT) and shielding effectiveness is not universal; it is highly dependent on the underlying physical shielding mechanism. In this segment, the critical distinction between reflective EMI shielding and magnetic conductive shielding is demystified. For reflective coatings containing silver or copper, the skin depth effect dictates that exceptionally thin layers—often just 10 to 15 microns—are highly sufficient to achieve maximum shielding performance.
Conversely, low-frequency magnetic shielding operates by conducting magnetic flux lines around sensitive components rather than reflecting them. Because this mechanism relies on magnetic reluctance and reluctance path volume, performance scale-up is directly proportional to material volume. As a result, magnetic coatings require much higher film thicknesses, often needing to be applied up to 500 microns to achieve optimal shielding effectiveness.
Understanding this trade-off is essential for material scientists and manufacturing engineers looking to optimize material usage and cost. Applying a reflective coating too thickly yields diminishing returns and adds unnecessary weight, while applying a magnetic conductive coating too thinly will fail to route low-frequency interference away from sensitive ICs.
In this short video, you can learn:
* The physical differences between reflective shielding and magnetic conductive routing mechanisms.
* Why reflective coatings function effectively at ultra-thin levels (10-15 microns) while magnetic shields require up to 500 microns.
* How to optimize dry film thickness to balance target attenuation, material cost, and component weight.
📋 **Clip Abstract** Explore how the physical mechanism of an EMI shield dictates its optimal coating thickness. This clip details why reflective paints excel at ultra-thin levels, whereas low-frequency magnetic shields must be applied significantly thicker to route interference away.
#EMIShielding, #DryFilmThickness, #SkinDepth, #MagneticReluctance, #PrintedElectronics, #ElectromagneticCompatibility
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00:06:54 - 00:08:28
Can a humble conductive paint really replace advanced physical vapor deposition sputtered coatings?
Can a humble conductive paint really replace advanced physical vapor deposition sputtered coatings?
Conventional board-level electromagnetic interference (EMI) shielding often relies on complex, expensive, and rigid metal cans or high-vacuum sputtering processes. In this clip, we discuss how advancements in robotically controlled precision spraying and vacuum screen printing enable the application of silver-based conductive paints directly onto individual microchips and components. This approach offers a highly conformable, additive alternative to conventional physical vapor deposition (PVD).
By utilizing automated dispensers, the fluid properties of these acrylic- and polyester-based conductive paints can be leveraged to fill precise gaps and coat complex 3D architectures. This eliminates the design limitations of rigid shielding tapes and sheets while drastically lowering capital expenditure associated with sputtering chambers.
From a commercial standpoint, transitioning from subtractive or high-vacuum deposition to an additive spray-on process yields significant material savings, faster cycle times, and simplified assembly lines. The resulting micro-coatings provide excellent attenuation in the megahertz range, making them highly viable for automotive electronics, medical hardware, and consumer devices.
In this short video, you can learn:
* How automated spray and vacuum printing technologies enable component-level EMI shielding without vacuum chambers.
* The key mechanical and rheological advantages of using conductive paints as conformal coatings over rigid metal shields.
* How to achieve weight and cost reductions in consumer electronics by replacing sputtered metal layers with precise additive coatings.
📋 **Clip Abstract** Discover how advanced robotic spraying and vacuum screen printing turn simple conductive paints into high-precision alternatives to sputtered metal coatings. This additive approach offers a cost-effective, lightweight method for component-level EMI shielding in complex electronic assemblies.
#ComponentLevelShielding, #ConductivePaints, #PrecisionSpraying, #VacuumScreenPrinting, #PrintedElectronics, #MicroelectronicsPackaging
00:09:19 - 00:10:43
Why is wave absorption, rather than reflection, the critical key to solving 5G and radar cavity resonance?
Why is wave absorption, rather than reflection, the critical key to solving 5G and radar cavity resonance?
As operating frequencies climb into the millimeter-wave (mmWave) spectrum for 5G and automotive radar, conventional metal shields that reflect electromagnetic interference (EMI) become a liability. Reflective surfaces inside device housings cause wave reverberation and cavity resonance, which severely degrade signal integrity. This clip introduces a carbon-epoxy composite paint designed to match the electrical impedance of free space, allowing waves to enter the material rather than bounce off it.
Once the mmWave signals enter the coating, the material's carefully balanced carbon-to-resin ratio drives high dielectric loss. This mechanism converts the unwanted electromagnetic energy into negligible, harmless heat, effectively damping the interference within the housing.
This sprayable, two-part epoxy system operates across the 30 GHz to 300 GHz spectrum, delivering up to 20 dB (90%) of attenuation at just a 150-micron dry film thickness. This represents a massive processing breakthrough over traditional pre-cut elastomer sheets or foam absorbers, which are notoriously difficult to apply to complex, miniaturized device geometries.
In this short video, you can learn:
* The physics of impedance matching and dielectric loss in carbon-filled polymer coatings for high-frequency attenuation.
* Why mmWave applications require absorbing coatings instead of reflective metal shields to prevent cavity resonance.
* The processing and cost advantages of sprayable carbon-epoxy absorbers over traditional die-cut foam and elastomer sheets.
📋 **Clip Abstract** Learn about a novel carbon-epoxy paint that suppresses high-frequency cavity resonance by absorbing mmWave signals instead of reflecting them. Operating up to 300 GHz, this material converts electromagnetic energy into heat through dielectric loss, presenting a major upgrade for 5G and radar systems.
#CavityResonance, #DielectricLoss, #CarbonEpoxyAbsorber, #SprayableEMIAbsorber, #AutomotiveRadar, #mmWaveTechnology