Molecular design and application of low dielectric bismaleimide resin

Abstract With the development of communications technology, the copper‐clad laminate (CCL) for integrated circuits (IC) pointed to the direction of high‐frequency and high‐speed development, that is, a lower dielectric constant and dielectric loss requirements. Bismaleimide (BMI) resins feature stable dielectric properties and excellent thermal stability over a wide temperature range, widely used in the manufacture of high‐frequency and high‐speed CCL substrates. However, the comprehensive performance of BMI resin itself, including dielectric properties, still cannot fully meet the needs of the ever‐changing communications industry, so the molecular design modification of BMI resin to enhance the dielectric properties is currently one of the key research directions for integrated circuit CCL. This paper reviews the development of BMI resins and their applications, focusing on the main methods of molecular design modification and formulation optimization, including allyl, diamine, internal chain‐extended, and chemical/physical blending modification. Finally, the low dielectric BMI resin and its application and development in high‐frequency and high‐speed CCL are summarized and prospected. Future research directions include the design and synthesis of multi‐component copolymers to further realize the balance between low dielectric and comprehensive performance, as well as exploring the possibility of novel composite modifications to provide more competitive high‐performance materials for the IC laminate field. Highlights The development of bismaleimide resin and their applications are reviewed. Bismaleimide monomers' synthesis and chemical reaction are summarized. The modified methods of bismaleimide resin in low dielectric are reviewed. Future research directions of low dielectric bismaleimide are prospected.