Mechanical enhancement and dielectric properties of SiO2 contained polyimides under high frequency.

Communication industry has developed relying on technological advancement in microelectronics and large-scale integrated circuits. Modified polyimide (MPI) materials with low dielectric loss, relatively simple fabrication process, and cost-effectiveness have significant social and economic benefits. In this work, 6FAPB and 6FDA were used to polymerize fluorinated PI films by thermal imidization, and SiO₂ was used to modify PI films for further obtaining low dielectric constant (ε)/loss (tanδ) and enhance mechanical properties. The values of dielectric constant (ε) and tan δ were 2.75 and 0.00491, respectively, under 10 GHz. Meanwhile, the elastic modulus of MPI films was enhanced by the SiO₂ adding process, with a maximum tensile modulus of 2.42 GPa. The results indicate that low polarity Si–O–Si bonds lead to a decrease in overall polarity of PI films and lead to tan decrease. This work provides a simple method to increase mechanical properties and reduce the dielectric constant/loss (at 10 GHz high frequency) of PI film by introducing trifluoromethyl and SiO₂. [ABSTRACT FROM AUTHOR]