Thin films growth by PIIID technique from hexamethyldisilazane/argon mixture

• We deposited films from HMDSN/Ar mixtures using PIIID.
• We studied the structure of the samples by FTIR.
• We studied the hardness and thickness of the samples by nanoindentation.
• We studied the wettability and surface energy of the films.
• We studied the optical properties (refractive index) of the films.

Plasma polymer thin films are pinhole-free and have also a high cross-linked structure. These kinds of films are insoluble in mild acids and bases and present good adhesion on different materials. These features make the films relevant for industrial applications and are used in different fields such as electronics, mechanics, biomedics, electrics, protective coatings and others. The plasma polymer hexamethyldisilazane/argon films (ppHMDSN/Ar) were deposited on substrates which were placed between two stainless steel parallel plate electrodes fed by a radio-frequency source operated at 13.56 MHz and 50 W at a total pressure (HMDSN and argon) of 80 mTorr. The negative bias of 10 kV and 10 Hz pulse were used for ion implantation. The structural characterization of the films was done by FTIR spectroscopy. The contact angle for water was of approximately 98° and the surface energy of 30 mJ/m2 which represents a hydrophobic surface, measured by goniometric method. The refractive index of these materials presents values from 1.56 to 1.64 measured by ultraviolet–visible technique. The thickness of the samples was measured by profilometry and showed values from 96 to 210 nm for different deposition conditions resulting in deposition rates from 4.8 to 10.5 nm/min. Hardness values ranging from 0.9 to 2.6 GPa were found for the films measured by nanoindentation technique.