Polyquinoline bismaleimide blends as low-dielectric constant materials

Low-dielectric constant (kappa) materials have attracted much attention in the field of microelectronics packaging. Currently a number of low dielectric constant polymers have been reported with kappa in the range of 2.2 to 3.0, however, hardly any polymer satisfies all desired material requirements. Polyquinolines are thermoplastic polymers which show low dielectric constant, high thermal stability, good mechanical strength and low moisture absorption. We have blended a polyquinoline designated as PQ-100 with a bismaleimide in order to improve physical properties for microelectronics packaging applications. We have prepared transparent, tough polyquinoline/bismaleimide blend thin films containing 5 to 60 weight % bismaleimide contents as low-dielectric constant interlayer materials for multilevel interconnections. The effect of bismaleimide loading and curing conditions on dielectric, dynamic mechanical. and thermal stability properties of polyquinoline/bismaleimide thermoset blends was studied. By the incorporation of the bismaleimide, the blend thin films showed higher glass transition temperature up to 360 degrees C. The dielectric, thermal and mechanical properties of polyquinoline/bismaleimide blend thin films are discussed.