The effect of hollow silica nanoparticle shell structure on the dielectric properties of polyimide composite films

• The effect of HNSP shell density and thickness on dielectric features were studied. • The HSNP-added PI film showed an extremely low dielectric constant of 3.85 at −1MHz. • This work provides guidance for the preparation of low dielectric HSNP composites. A hollow silica nanoparticle (HSNP)/polyimide (PI) composite is expected to be applied to a low dielectric constant material for semiconductors. The effect of the shell structure of the HSNP on the HSNP/PI composite’s dielectric properties was investigated. The results indicated that the dielectric constant and dielectric loss of HNSP/PI composite film can be lowered by reducing the HSNP shell thickness (increase the air proportion) or decreasing the HSNP density (reduce the dipole polarization in electric field). When the shell thickness of HNSP decreases from 37.94 nm to 13.81 nm, the shell density decreases from 1.95 g/cm 3 to 1.75 g/cm 3 , the HSNP content increases from 0 vol% to 20 vol%, the HSNP/PI composite film dielectric constant reduces from 4.42 to 3.85(at 1 MHz). The effect of the hollow particles’ shell configuration on the composite’s dielectric properties was also clarified. These findings can help to promote the further application of hollow particles in low-dielectric materials.