Novel ether-bridged fluorinated poly(phenylquinoxaline) (PEPPQ) dielectric films with enhanced glass-transition temperatures (T-g) have been developed in order to meet the high temperature demands for interlayer dielectrics used in microelectronic fabrication. The PEPPQ films were prepared from newly-developed aromatic bis(alpha-diketone) monomers containing ortho-substituted methyl groups (2-1) or a fluorene moiety (2-2) in their molecular structures. The obtained PEPPQ films exhibited excellent combined properties, including high thermal stability with T-g over 260 degrees C, high electrical insulating characteristics with a volume resistivity of over 10(17) Omega cm, and a dielectric strength higher than 212 V mu m(-1). Besides, the bulky substituents and low-molar-electronegative trifluoromethyl groups endowed the polymers with low dielectric constants (D-K < 2.82 at 1 MHz) and good water repellent property.