The Isola FR408HR is a high-performance FR-4 resin system designed for multilayer PCB applications that require maximum thermal performance and reliability. This material is particularly suitable for environments where lead-free assembly is mandatory and high thermal endurance is crucial. With a glass transition temperature (Tg) of 190°C and a decomposition temperature (Td) of 360°C, FR408HR ensures stability and integrity under high thermal stresses, making it ideal for high-density and high-power applications .

Key features of FR408HR include its compatibility with FR-4 processing, which simplifies integration into existing manufacturing lines without the need for additional equipment or changes in standard procedures. It also boasts excellent moisture resistance at reflow temperatures, which helps in maintaining performance in humid conditions. Additionally, the material is CAF resistant and capable of withstanding multiple lamination cycles, which is beneficial for complex PCB designs .

FR408HR is available in various forms including laminate and prepreg, with options for different copper weights and types of glass fabric, such as E-glass and square weave glass. This versatility makes it suitable for a wide range of applications from basic to advanced circuit designs. Here are some key considerations for using FR408HR in PCB stackup:

• Ensure compatibility with lead-free soldering processes, as FR408HR can handle up to six times reflow at 260°C and solder float at 288°C.
• Utilize its via filling capabilities for high-density interconnect (HDI) designs.
• Consider its laser fluorescing and UV blocking properties for enhanced compatibility with Automated Optical Inspection (AOI) systems.
• Take advantage of its high thermal and electrical performance for applications requiring robust thermal management and signal integrity.

Overall, FR408HR provides a robust solution for advanced PCBs, bridging the gap between thermal and electrical performance requirements, making it an excellent choice for demanding applications .