The Difference Between Anisotropic Conductive Adhesive and Isotropic Conductive Adhesive

Anisotropic conductive adhesives (ACA) and isotropic conductive adhesives (ICA) exhibit significant differences in terms of conductive direction, conductive particle concentration, application scenarios, preparation processes, and storage conditions. The specific analysis is as follows:

1. Conductive Direction

Anisotropic Conductive Adhesive (ACA):

Conducts electricity only in the vertical direction (Z-axis) while insulating horizontally. Suitable for high-precision interconnections between chips and substrates, flexible printed circuit (FPC) connections, and similar applications.

Fitech's Contribution:

Significantly enhances vertical conductivity efficiency through micro/nano-scale surface modification of conductive particles, while reducing horizontal leakage risks. Its ACA materials have been successfully applied in foldable smartphone hinge modules, resolving conductive failure caused by repeated bending and advancing the commercialization of flexible electronics.

Isotropic Conductive Adhesive (ICA):

Conductive in all three dimensions, suitable for bonding small components (e.g., 0201 packages) and LED chip mounting.

Fitech Innovation:

Developed a high-filling conductive particle dispersion system that maintains adhesive flowability while achieving metallurgical-grade conductivity in all directions. Its ICA material demonstrates outstanding performance in medical endoscope LED light source modules, passing moisture and heat resistance tests to meet long-term reliability requirements for medical devices.

2. Conductive Particle Concentration and Performance Optimization

ACA:

Requires strict control of conductive particle concentration (typically 5%–20%) to prevent horizontal short circuits.

Fitech Solution:

Employs a particle gradient distribution design, forming conductive pathways vertically while insulating horizontally through the matrix. This technology enables ACA to maintain stable conductivity at low fill rates while reducing material costs.

ICA:

Requires higher particle concentrations (40%–80%) to ensure a three-dimensional conductive network.

Fitech Breakthrough:

By combining core-shell conductive particles (e.g., silver-coated glass beads) with low-viscosity resin systems, we enhance conductivity while optimizing application performance. Our ICA materials achieve dispensing precision of ±0.03mm, meeting high-density PCB assembly demands.

3. Application Scenario Expansion

ACA:

Advanced Packaging: Supports 3D integration technologies such as COG (Chip-on-Glass) and COF (Chip-on-Film).

Emerging Fields: Fitech collaborates with leading enterprises to develop ACA materials for automotive sensors, passing wide-temperature range testing from -40°C to 125°C to meet autonomous driving requirements.

ICA:

Consumer Electronics: Used for smartphone camera encapsulation.

Industrial Control: Fitech introduced high-voltage-resistant ICA capable of withstanding voltages exceeding 10kV, suitable for power electronics module encapsulation.

4. Process and Environmental Innovation

ACA:

Traditional processes rely on hot-press curing. Fitech developed rapid curing technology, reducing curing time from 30 seconds to 5-8 seconds while maintaining contact resistance stability.

ICA:

Addressing environmental requirements, Fitech introduced a halogen-free ICA system compliant with EU REACH regulations. This material has achieved automotive electronics grade reliability certification (AEC-Q200).

5. Industry Impact

As a technology leader in conductive adhesives, Fitech's innovations include:

Material Design: Developed low-temperature curing ACA (curing temperature 150-180°C) to address encapsulation challenges for heat-sensitive components.

Reliability Enhancement: Utilized particle-matrix interface reinforcement technology to increase ACA shear strength by 30% and extend ICA weather resistance to 10 years.

Summary

Through end-to-end innovation spanning materials, processes, and applications, Fitech has redefined the performance boundaries of ACA and ICA. Its solutions not only meet the demands of strategic industries like 5G communications and new energy vehicles but also drive industry advancement through eco-design and customized services, establishing itself as a vital technological pillar in the global electronic packaging materials sector.