We have fabricated and measured the room-temperature capacitance in metal-insulator-metal (MIM) structures utilizing the Parylene C films as the insulators in the frequency range 1 kHz to 1 MHz. The Parylene-C films were of variable thicknesses and were either spin-on dense films or columnar microfibrous thin films (μFTFs) grown using oblique angle physicochemical vapor deposition. The values of the vapor tilt angle, χ_v, used were 30°, 60°, or 90°. Expectedly, columnar microfibrous thin film of Parylene C is observed to have lower values of k than the dense one. However, it is observed that the dielectric constant of the μFTFs is increased with increasing deposition tilt angle χ_v. This is explained in terms of film porosity as a function of χ_v, which is enhanced in films deposited at lower tilt angles. The dependence of k on measurement frequency suggests that molecular dipole effects dominate charge polarization in the films.
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