The Amorphous Carbon Thin Films Synthesized by Gas Injection Magnetron Sputtering Technique in Various Gas Atmospheres

Abstract

This work presents the potential for using pulsed gas injection to produce amorphous carbon films. In this experiment, the frequency of injecting small amounts of gas was used to control the pressure amplitudes, thus achieving the conditions of plasma generation from stationary, through quasi-stationary, to pulsed oscillations of pressure. In addition, we used various gases and their mixtures, an alternative to argon. In the experiment, we studied the energy state of the plasma. The films were examined for phase and chemical composition, surface morphology, and optical and mechanical properties. We determined low-frequency pulsed gas injections to be conditions favorable for C(sp3) − C(sp3) bond formation. The plasma generated by gas injections is better ionized than that generated by static pressure. Pulsed conditions favor the plasma species to retain their kinetic energy, limiting the probability of intermolecular collision events. Since helium has a relatively high ionization energy, it is a practical addition to sputtering gas because of the increasing sp3 content in the films. The electrons created by helium ionization improve the plasma’s ionization degree.

Optical Properties of Amorphous Carbon Thin Films Fabricated Using a High-Energy-Impulse Magnetron-Sputtering Technique

“…The XPS technique is a surface-sensitive method and, in contrast to the Raman measurements, where the recorded signal comes from the whole film, provides us with information only about the surface (subsurface) state of the sample. Such discrepancies between the composition of the carbon films were observed earlier [48,57,58]. Optical measurements show a significant difference in the properties of the fabricated a-C films.…”

Influence of Carbon ionization increment by adding Ne on the Bonding, Electrical, and Tribological properties of Carbon Thin Films deposited by HiPIMS

“…Gas Injection Magnetron Sputtering (GIMS) is an implementation in which the gas injection frequency is reduced, and gases with ionization energy higher than that of argon or a mixture of these gases are used. In the GIMS process, helium-argon has been reported to exhibit a higher sp 3 /sp 2 ratio [21]. Another promising alternative to increase carbon ionization is the High-power Impulse Magnetron Sputtering (HiPIMS) technique, which generates discharges with relatively high plasma densities and exhibits high ionization energies in metal targets.…”

Surface Roughness Effects on the Properties of Silicon-Doped Diamond-like Carbon Coatings

“…Various surface modification techniques (polishing, sandblasting, etching), ion implantation, or deposition of thin hard coatings are available [21][22][23][24]. Examples include diamond-like carbon (DLC) coating type a-C:H characterized by high hardness due to sp 3 bonds (typical in diamond) and excellent lubrication properties due to sp 2 bonds (typical in graphite) [25][26][27][28][29].…”