A superhydrophobic fluorinated-silica/polyimide nanofiber membrane with ultra-low dielectric constant

For ultra-large-scale integrated circuits to proceed at a rapid pace, dielectric materials with an ultralow permittivity, excellent mechanical properties, and moisture resistance are highly sought after. Herein, a series of F-SiO2/PI nanofiber films with an ultralow-k value have been successfully created by coaxial electrospinning and in situ sol-gel techniques, allowing them to be used under moisture conditions. Thanks to the introduction of fluorinated substituents and high porosity, F-SiO2/PI films exhibited ultralow dielectric constants, less than 1.8 at 1 MHz, and high hydrophobicity with contact angles greater than 145 degrees. In addition, when TEOS was added in quantities ranging from 0.25 to 1.00 ml, F-SiO2/PI films with dielectric constants of 1.81-2.65 (1 MHz) at 80% R.H., and the water contact angles of 146.1 degrees, 148.0 degrees, 151.9 degrees, and 154.2 degrees, respectively, were obtained, compared to 4.17 of dielectric constant at 80% R.H. and contact angle with water 112.0 degrees for pure PI nanofiber films. In this regard, the F-SiO2/PI films offered great promise as an insulating material for electronics and microelectronics.