Thermal, mechanical, and conductivity properties of cyanate ester composites

Abstract Cyanate ester resins have been widely proposed as replacements for epoxy resins in high temperature applications. One such application, semiconductor encapsulation, uses a large amount of inorganic filler, typically 65 wt%. The effect of filler incorporation, on the properties of cyanate ester composites, was assessed incrementally in this work. It was found that, as is the case with epoxy based encapsulants, silica filler increased cyanate ester composite thermal conductivity, Young's modulus, and dielectric constant (slightly), and decreased encapsulant thermal expansion. It was also found that silica addition resulted in a marginal decrease in strength. This indicated a high degree of interfacial adhesion between the untreated silica filler and the cyanate ester matrix, a conclusion supported by work by Possart et al. [1] .