Nanocomposite–parylene C thin films with high dielectric constant and low losses for future organic electronic devices

Abstract

Nanocomposite–parylene C (NCPC) thin films were deposited with a new technique based on the combination of chemical vapor deposition (CVD) for parylene C deposition and RF-magnetron sputtering for silver deposition. This method yields good dispersion of Ag-containing nanoparticles inside the parylene C polymer matrix. Film composition and structure were studied by using several techniques. It was found that the plasma generated by the RF-magnetron reactor modifies the film density as well as the degree of crystallinity and the size of parylene C crystallites. Moreover, silver is incorporated in the parylene matrix as an oxide phase. The average size of the Ag oxide nanoparticles is lower than 20 nm and influences the roughness of the NCPC films. Samples with various contents and sizes of silver-oxide nanoparticles were investigated by broadband dielectric spectroscopy (BDS) in view of their final application. It was found that both the content and the size of the nanoparticles influence the value of the dielectric constant and the frequency-dependence of the permittivity. In particular, β-relaxation is affected by the addition of nanoparticles as well as the dissipation factor, which is even improved. A dielectric constant of 5 ± 1 with a dissipation factor of less than 0.045 in the range from 0.1 Hz to 1 MHz is obtained for a 2.7 µm thick NCPC with 3.8% Ag content. This study provides guidance for future NCPC materials for insulating gates in organic field-effect transistors (OFETs) and advanced electronic applications.

Frequency Dependent Negative Dielectric Behavior in Parylene C Based Composite Films

“…It can be seen that polarisation reduces the negative permittivity values (Figure 1d). Mokni et al (2019) measured the dielectric permittivity value of PAC to be approximately 5 at a frequency of 1 MHz. In other studies, results are obtained that show a low dielectric permittivity (Kahouli et al, 2009;Hu et al, 2022).…”

Implantable application of polymer‐based biosensors

“…Their applications in wearable electronics further promote the development of flexible polymeric materials. Amounts of polymeric semiconductors (e.g., poly(3-hexylthiophene) (P3HT), polyethylene (PE), 52 diketopyrrolopyrrole (DPP)-2,6-pyridine dicarboxamide (PDCA) 53 ) and insulators (e.g., polyvinyl alcohol (PVA), 54 Parylene-C, 55 poly(methyl meth-acrylate) (PMMA) 56 ) have been synthesized to construct electronic devices with high flexibility and performance. Some of them have also been proven feasible in implantable application for their advantageous properties in mechanics and biocompatibility (Figure 3), such as poly (L-lactic acid) (PLLA), 24d poly(lactide-co-glycolide) (PLGA), 24e polyvinylidene fluoride (PVDF), 57 poly(pyrrole) (Ppy), 25a and poly(3,4-ethy-lenedioxythiophene (PEDOT): polystyrene sulfonate (PSS).…”

Advanced hybrid nanomaterials

“…Regarding specific applications, the dielectric properties were investigated by broadband dielectric spectroscopy (BDS) in "Nanocomposite-parylene C thin films with high dielectric constant and low losses for future organic electronic devices" [29]. A combination of deposition techniques was used, chemical vapor deposition for parylene and RF-magnetron sputtering for silver nanoparticles.…”