Chapter 4 - Cyanate Ester Resins with Low Dielectric Properties and Applications

Abstract

Cyanate ester resins were recognized from a consideration of polymer structure that these resins had potential for low dielectric applications. The processing characteristics, chemical versatility, and properties associated with this class of thermoset resins have qualified it for low dielectric applications that include printed circuit boards, microelectronic interconnects, antenna coatings, radomes, and sonar domes. This chapter reviews the chemistry and structure–property relationships of cyanate ester resins that are relevant to low dielectric applications. The uniqueness of the cyanate ester resin resides in its polymerization and structure. It is a simple one-component thermoset system with a simple well-defined network structure. This provides a solid foundation on which scientific structure–property studies are built. The high symmetry and low polarity of the network structure are responsible for the low dielectric character of this resin system. The limits as to how low the cyanate ester resin dielectric constant can be pushed may be extrapolated are described in the chapter. For applications, there are always tradeoffs between conflicting properties and between cost and performance. In the future, performance demands for low dielectric materials will inevitably increase, as more is demanded from microelectronics and communications. Based on the currently known property database, the materials availability, and the processing simplicity, cyanate ester resins have a healthy performance to cost ratio.