Dielectric loss in thin films of an aromatic polyimide

The dielectric response of thin aromatic polyimide films with thicknesses ranging from 40 nm to 3 μm has been measured in the frequency range of 104-108 Hz. The dielectric loss shows a frequency-independent behavior regardless of film thickness, which is attributed to the dipolar response of the dielectric lattice. Film morphology is found to affect the magnitude of the dielectric loss but not its frequency dependence.