The Isola FR408 is a high-performance FR-4 epoxy laminate and prepreg system designed for advanced circuitry applications, featuring a glass transition temperature (Tg) of 180°C and a decomposition temperature (Td) of 360°C. With a dielectric constant (Dk) of 3.67 and a dissipation factor (Df) of 0.0120, FR408 is particularly suited for broadband circuit designs that require faster signal speeds or improved signal integrity. The material's compatibility with most FR-4 processes allows for seamless integration into existing manufacturing setups without additional complexity.

When building a PCB stackup using FR408, consider the following guidelines:

• Choose the appropriate copper foil type and weight based on your circuit's current carrying requirements and thermal management needs. FR408 is available with HTE Grade 3 and RTF (Reverse Treat Foil) copper, with weights ranging from ½ to 2 oz (18 to 70 µm).
• Utilize the material's low Dk and Df properties to enhance the performance of high-speed digital and RF applications, ensuring better signal integrity and reduced signal loss.
• Ensure that the stackup design accommodates the thermal properties of FR408, particularly its Tg and Td, to maintain structural integrity and reliability under thermal stress.

FR408's processing advantages include compatibility with UV blocking and AOI fluorescence, which facilitates easier inspection and quality control during PCB fabrication. Additionally, the material's robust physical and thermal properties make it a reliable choice for multilayer PCBs that require high reliability and performance in demanding applications.