This report focuses on the specialized application of SMA (Styrene-Maleic Anhydride Copolymer) in high-frequency and high-speed CCL interconnect boards, as well as the current status of the electronic materials industry from 2025 to 2026.
CCL interconnect boards are hybrid copperclad laminates that are compatible with both conventional multilayer through-hole boards and high-frequency/high-speed blind-buried via boards. They are widely used in 5G base stations, AI servers, computing motherboards, high-end industrial controls, automotive electronics, and other fields.
With its low dielectric loss, high thermal stability, excellent epoxy compatibility, strong adhesion, low water absorption, and moisture-heat resistance, SMA has become a core modified curing material in the resin system of interconnect boards. It is a key additive for reducing Df, improving heat resistance, preventing CAF failure, and enhancing lamination yield in current high-frequency CCLs. The trend of replacing traditional amine-based and phenolic hardeners is clear.
Product Fundamentals and Application Value in CCL Interconnect Boards
Core SMA Product Characteristics (CCL-Specific Metrics)
SMA specially designed for CCL interconnect boards is a styrene-maleic anhydride copolymer resin. By adjusting the anhydride content, molecular weight, and styrene/anhydride ratio, it can be tailored for different grades of interconnect board systems. Key parameters are as follows:
Molecular Structure: Styrene/maleic anhydride molar ratio of 3:1 to 6:1, anhydride content of 15%–30%, providing stable active sites for epoxy ring-opening curing.
Thermal Performance: Glass transition temperature (Tg) of 120–160°C, thermal decomposition temperature >300°C, fully compatible with lead-free 260°C reflow soldering processes.
Dielectric Properties: At 10 GHz, Dk of 3.0–3.5 and Df of 0.002–0.005, making it a critical low-loss material for high-frequency interconnect boards.
Process Adaptability: Lowers the curing temperature and shortens the curing cycle of the resin system, reduces internal stress in laminates, and effectively improves issues such as blistering, delamination, and warpage.
Reliability: Significantly enhances moisture-heat resistance and resistance to CAF (conductive anodic filament) migration, greatly improving the long-term service reliability of high-end interconnect boards.
Core Application Value
Performance: Balances four key parameters—low dielectric constant, high heat resistance, strong adhesion, and low CTE—addressing the shortcomings of traditional curing agents, such as high high-frequency loss, insufficient heat resistance, and weak adhesion.
Process: Gradient curing is well-suited for the multilayer lamination process of interconnect boards, improving production yield and reducing plant energy costs.
Cost: Domestically produced SMA enables import substitution, achieving comparable performance while significantly lowering the raw material cost of high-end CCL.
Trend: Aligned with the high-frequency upgrades of 5G, AI computing, and high-speed servers, SMA is poised to become a standard ingredient in next-generation high-end interconnect board formulations.
