EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Initiated Chemical Vapor deposition (iCVD) is an original technique for the fabrication of polymeric thin films. This method relies on the radical polymerization under vacuum, which takes place on a cooled substrate. The main advantages that render iCVD a very promising method for polymer thin films deposition are the low substrate temperature, the absence of solvent, the large range of monomers that can be used and the possibility to preserve “delicate” functional groups of the monomer structure. In this work, an organosilicate polymer, the p(V3D3), formed from the precursor trivinyltrimethylcyclotrisiloxane was deposited and studied as a low-k dielectric material for use in microelectronics for the realization of capacitors. More precisely, the thickness of the films has been varied from few nm to several microns and the physicochemical along with the mechanical properties were investigated. This study shows that the p(V3D3) is polymerized in uniform thin films on all the surface of a 200 mm Si wafer, for both thinner and thicker films. The polymer has also been conformably deposited on substrates with 3D structures for the evaluation in integrated capacitors. The deposition rate which depends on the process conditions, is constant for all deposition times. AFM, FTIR and ellipsometry results confirm that the obtained polymer is amorphous, cross-linked, and composed of siloxane rings and polyethylene chains. Moreover, the polymer composition remains similar and relatively independent of the film thickness. Electrical tests that were made in order to evaluate the dielectric properties of the material reveal a low dielectric constant (<3), low leakage currents (few nA/cm2 at 1 MV/cm) and high breakdown voltage (higher than 7 MV/cm). These characteristics are maintained over the whole range of thickness studied, which positions this material as a state of the art dielectric polymer for high-voltage applications.