Sven Hujo | DELO Industrial Adhesives: What if your adhesive could not only secure your microLEDs but also boost their light output?
00:05:44 - 00:07:03
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Summary of the clip:
What if your adhesive could not only secure your microLEDs but also boost their light output?
Even when using traditional solder reflow, challenges like void formation under the die can compromise thermal and mechanical performance. A capillary underfill, a low-viscosity adhesive dispensed next to the chip, wicks underneath via capillary action to fill these voids. This process secures the die, prevents movement during subsequent reflow steps, and significantly reinforces the fragile solder joints against mechanical stress.
The mechanical reinforcement provided by an underfill dramatically improves the overall reliability of the assembly, especially for components with gap sizes below 50 micrometers. It increases the die shear strength and protects the component from stresses induced by thermal cycling and mechanical shock or vibration. This is particularly crucial for devices with small components and fine-pitch interconnects, where the solder joints themselves are inherently weak.
Underfills can be engineered for more than just mechanical support. By incorporating white, reflective fillers into the adhesive formulation, the underfill can act as a micro-reflector around the base of the LED chip. This white underfill scatters and reflects light that would otherwise be absorbed or trapped by the substrate, effectively increasing the total light output and improving the overall efficiency of the display package.
In this short video, you can learn:
* How capillary underfills eliminate voids and reinforce solder joints in micro-assembly.
* The role of underfills in improving die shear strength and overall device reliability.
* The novel use of white, reflective underfills to increase the light output of LED packages.
š **Clip Abstract** This clip explains the function and benefits of capillary underfills in advanced electronic packaging. It details how these materials reinforce solder joints to improve mechanical reliability and can even be formulated with white fillers to enhance the light output of LED components.
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#CapillaryUnderfill, #MicroLEDs, #SolderJointReliability, #ReflectiveUnderfill, #ARdisplays, #AdvancedPackaging
This is a highlight of the presentation:
Investigation of Electrically Conductive Adhesives for Miniaturized SMD Components
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00:04:01 - 00:05:08
Why do high-yield micro-assembly lines rely on dual-stage light and thermal curing instead of single-step mechanisms?
Why do high-yield micro-assembly lines rely on dual-stage light and thermal curing instead of single-step mechanisms?
To achieve high-yield assembly of ultra-miniature components like microLEDs, relying on a single curing mechanism often introduces risk. Thermal curing takes time and can lead to thermal expansion-induced drifting, while pure UV curing cannot reach shaded areas underneath the die.
By utilizing a dual-stage process, an initial ultra-fast UV light curing step instantly freezes the component's position within seconds. This initial structural fixation prevents physical misalignment during subsequent transport and bulk handling.
The assembly is then transferred to a thermal oven for bulk curing, ensuring maximum cross-linking density and structural integrity. This hybrid approach eliminates position drift and drastically improves process yield in automated high-throughput manufacturing lines.
In this short video, you can learn:
* How dual-stage UV-thermal curing eliminates component drift during pick-and-place
* The physical mechanisms of light-activation versus secondary thermal cross-linking
* Best practices for securing high-precision optical and electrical alignments
š **Clip Abstract** This clip covers how hybrid curing processes stabilize precise electronic assemblies during automated production. By combining rapid UV fixation with bulk thermal curing, manufacturers can prevent component drift and ensure high reliability.
#DualStageCuring, #UVThermalCuring, #MicroAssembly, #ComponentDrift, #MicroLEDDisplay, #AdvancedPackaging
00:13:02 - 00:14:45
How do you prevent conductive particle migration when jetting two liquid adhesives side-by-side?
How do you prevent conductive particle migration when jetting two liquid adhesives side-by-side?
Integrating structural and electrical bonds in a single micro-assembly step requires dispensing distinct chemistries in close proximity. When liquid Non-Conductive Adhesives (NCA) and Isotropic Conductive Adhesives (ICA) are co-dispensed, they must possess absolute chemical and rheological compatibility.
Without precise rheological control, the silver particles from the conductive ICA will migrate and diffuse into the neighboring NCA channel. This uncontrolled particle percolation degrades mechanical adhesion and introduces massive lateral short-circuit risks under high-density arrays.
Achieving a pristine, sharp boundary under microscopes requires formulating precise viscosity, thixotropy, and surface tension compatibility. Successfully engineered systems maintain distinct boundaries even when applied as sub-millimeter co-jetted droplets.
In this short video, you can learn:
* The critical role of rheological matching in multi-material micro-assembly
* Why silver particle diffusion across liquid boundaries causes devastating electrical failures
* Technical criteria for evaluating chemical co-compatibility during simultaneous jetting operations
š **Clip Abstract** This clip explores the complex physics of dispensing non-conductive and conductive adhesives in immediate physical contact. It highlights how rheological engineering prevents particle diffusion, protecting high-density arrays from catastrophic lateral short circuits.
#IsotropicConductiveAdhesives, #RheologicalMatching, #JetDispensing, #ParticleMigration, #AdvancedPackaging, #MicroAssembly
00:07:00 - 00:08:35
Are you choosing the right conductive adhesive category for fine-pitch microelectronic interconnects?
Are you choosing the right conductive adhesive category for fine-pitch microelectronic interconnects?
Selecting the appropriate electronic adhesive requires a fundamental understanding of electrical percolation pathways. Non-conductive adhesives (NCAs) serve primarily as mechanical anchors where electrical contact is maintained purely through physical bump-to-pad force.
Conversely, Isotropic Conductive Adhesives (ICAs) distribute conducting particles uniformly in three dimensions, making them highly effective for uniform bulk connections like grounding but prone to short-circuits in high-density pitches.
For sub-millimeter pitch assemblies such as micro-bumped flip chips and RFIDs, Anisotropic Conductive Adhesives (ACAs) isolate conductivity strictly along the vertical compression axis, enabling multi-terminal connectivity down to the micron scale.
In this short video, you can learn:
* The mechanical and electrical differences between NCA, ICA, and ACA technologies
* Why ICA materials pose a high risk of lateral short circuits in fine-pitch arrays
* How ACA particle sizes enable isolated vertical conductivity for advanced flip-chip packaging
š **Clip Abstract** This clip breaks down the selection criteria and technical distinctions among non-conductive, isotropic, and anisotropic adhesives. It explains how selecting the appropriate electrical pathway geometry prevents shorts in miniaturized semiconductor packages.
#AnisotropicConductiveAdhesives, #FinePitchInterconnects, #ElectricalPercolation, #IsotropicConductiveAdhesives, #AdvancedPackaging, #FlipChipAssembly