Rapid Electro-Deposition of H_2 Free Quality Diamond Like Carbon Films on Stainless Steel 304 Substrate Using a Nanocrystalline SnO_2 Interlayer

摘要

Good quality diamond like carbon (DLC) films are deposited on bare as well as nanocrystalline SnO_2 layer coated stainless steel 304 substrates. SnO_2 film is deposited on stainless steel substrates by electrolysis of 10mM SnCl_2 solution in nitric acid medium and then subsequently heating the sample in oxygen ambient conditions. The carbon film on the other hand, is prepared by dissociative cleavage of methanol under high D.C. potential of 1kV. Deposition conditions are optimised to get best quality films, which are characterized by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and Atomic Force Microscopy (AFM). It has been observed that films with SnO_2 interlayer grow much faster than those without it. It is believed that the SnO_2 layer acts both as protective barrier against carbon diffusion into the SS substrate and also promotes nucleation due to anchorage of CH_3~+ and H~+ radicals (necessary for growth of DLC film) onto its oxygen deficient sites.