author = "Capote, Gil and Mastrapa, G. and Trava-Airoldi, Vladimir Jesus",
          affiliation = "{Universidad Nacional de Colombia} and {Pontif{\'{\i}}cia 
                         Universidade Cat{\'o}lica do Rio de Janeiro (PUC-Rio)} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)}",
                title = "Influence of the Acetylene Precursor Dilution with Argon on the 
                         Microstructure, Mechanical and Tribological Properties of aC:H 
                         Films Deposited by Modified Pulsed-DC PECVD Method",
                 year = "2015",
         organization = "The International Conference on Metallurgical Coatings and Thin 
                         Films, 42. (ICMCTF).",
             abstract = "Amorphous hydrogenated carbon (a-C:H) films have been grown using 
                         different hydrocarbon precursors in order to find the best set of 
                         mechanical and tribological proprieties. The addition of noble 
                         gases to the hydrocarbon precursor atmosphere is expected to 
                         increase the ratio of ion to neutral radicals on the surface of 
                         the growing film without changing the H/C ratio of the gas 
                         mixture. This is in fact a powerful way to investigate the effect 
                         of ion bombardment on the structural arrangement and properties of 
                         a-C:H films. In this work, acetylene (C2H2) was be studied using 
                         argon as an inert additional gas, in order to determine the 
                         mechanical and tribological properties and microstructure of a-C:H 
                         films. The films were deposited employing an asymmetrical bipolar 
                         pulsed-DC plasma enhanced chemical vapor deposition (PECVD) system 
                         and an active screen that worked as an additional cathode. The 
                         a-C:H films were analyzed according to their microstructure, 
                         mechanical, and tribological properties as a function of the 
                         amount of argon diluted in the acetylene. The films microstructure 
                         and the hydrogen contents were probed by means of Raman 
                         spectroscopy. The internal stress was determined through 
                         measurement of the change in the substrate curvature by means of a 
                         profilometer, while nanoindentation experiments allowed to 
                         determinate the hardness and the elastic modulus of the film. The 
                         friction coefficient and wear resistance of the films were 
                         determined using a tribometer, while the adhesion of the films was 
                         evaluated via the scratch test. In order to improve the a-C:H 
                         films adhesion to steel substrates, a thin amorphous silicon 
                         interlayer was used. The results showed that the atmosphere of 
                         argon diluted in acetylene induced modifications in the properties 
                         of the a-C:H films. Hard, adherent, low-stress, and high wear 
                         resistant a-C:H films were deposited on steel substrates using a 
                         combination of a modified and asymmetrical bipolar pulsed-DC PECVD 
                         system, an active screen as additional cathode, and 
                         acetylene-argon atmospheres. The use of an amorphous silicon 
                         interlayer improved the a-C:H films deposition onto steel 
                         substrates. These results suggest that the used methodology 
                         represented a step forward for thin film growth by using lower 
                         pressure and higher plasma density than the conventional PECVD 
                         system and may represent a new and useful alternative for 
                         mechanical and tribological applications.",
  conference-location = "San Diego, California",
      conference-year = "20-24 apr.",
             language = "en",
        urlaccessdate = "02 dez. 2020"