Deposition Rate Of Diamond-like Carbon Film Research Articles

Hydrogen-free DLC films fabricated using superimposed HiPIMS-DCMS deposition system: Bias voltage effects

Diamond-like carbon (DLC) films were grown using a superimposed high-power pulse magnetron sputtering and direct current magnetron sputtering (HiPIMS-DCMS) deposition system at various bias voltages from 0 to −350 V. The microstructure, mechanical and tribological properties of the films were studied in relation to bias voltage. The results suggested that the deposition rate of DLC films decreased gradually with the enhancement of bias voltages. The surface roughness of DLC films decreased from 2.81 nm to 0.54 nm. The values of ID/IG of DLC films decreased first and increased later with the enhancement of bias voltages, and the value of ID/IG was the minimum at −150 V. Therefore, the highest sp3 CC fraction of DLC film was obtained when deposited at −150 V. Moreover, the hardness and internal stress of DLC films also show the law of increasing first and decreasing later. DLC film obtained the maximum hardness and highest internal stress of 32.0 GPa and − 2.08 GPa at −150 V. Finally, the friction test suggested that the films had excellent tribological performance. In particular, the film deposited at −150 V had excellent tribological properties, including low friction coefficient (0.095) and low wear rate (1.36 × 10−7 mm3/N·m).

Ultra-high-rate deposition of diamond-like carbon films using Ar/C2H2 plasma jet CVD in combination with substrate-stage discharge

Diamond-like carbon (DLC) films with excellent mechanical properties are used as functional surface protective films for cutting tools. The deposition rate of DLC films using conventional plasma chemical vapor deposition (CVD) methods is several hundred nm min−1. This study applied a negative DC pulsed voltage to a substrate stage irradiated with an Ar/C2H2 mixed plasma jet. The effect of the voltage applied to the stage on the fabricated DLC films was investigated based on the thicknesses and characteristics of the films. DLC films were formed on Si substrates using an Ar/C2H2 plasma jet CVD system. Ar plasma was ejected from a circular nozzle, and C2H2 gas was supplied as a carbon source gas from the center of the circular nozzle. DLC films with a nanoindentation hardness of 17 GPa were obtained by applying −500 V to the stage with a deposition rate of 2140 nm min−1.

Rapid Growth of Diamond-like Carbon Films by Nanopulse Magnetron Chemical Vapor Deposition

In this paper, we describe the development of a rapid deposition method for diamond-like carbon (DLC) films. The deposition rate of DLC films is investigated using magnetic field enhanced nanopulse plasma chemical vapor deposition (CVD). The maximum deposition rate of DLC films produced by this magnetron CVD is approximately fifty times larger than that of the same films produced by conventional plasma CVD. The area of DLC films having a high deposition rate corresponds to the region of the magnetic field distribution where the field is parallel to the substrate at heights of 15–20 mm.

Influence of duct bias on deposition rate of DLC film in T-shape filtered arc deposition

Diamond-like carbon (DLC) films were deposited by a T-shape filtered arc deposition (T-FAD) apparatus, applying bias voltage to the plasma transportation duct which filters the macrodroplet emitted from the cathode, in order to obtain a higher deposition rate. Ion current, deposition rate, discharge voltage, duct current, and anode current were measured as a function of duct bias. The anode current decreased and the duct current increased when a positive bias was applied to the duct. This fact indicates that the T-shape duct acted as another anode of the vacuum arc discharge. It was found that the maximum deposition rate as well as the ion current was obtained at about 15 V of duct bias. Improvement in plasma transportation to the process chamber through the duct was considered from the viewpoint of the characteristics of duct current against bias voltage. The value of the optimum duct bias was the same as the intersection point of the characteristics of duct current against bias voltage.

Negative pulsed voltage discharge and DLC preparation in PBIID system

The spectrum of optical emission from the plasma of hydrocarbon gases was measured with a photomultiplier and an optical multichannel analyzer in PBIID (plasma-based ion implantation and deposition) system. When negative pulsed voltage was applied to a sample, a strong optical emission was observed. It is important to know a contribution of negative pulsed voltage discharge on DLC (diamond-like carbon) synthesis. Spectra of CH (431 nm), H α (656 nm), H β (486 nm) and H γ (434 nm) were observed. Deposition rate of DLC film using acetylene gas was almost proportional to intensity of CH spectrum.

Deposition of diamond-like carbon films by plasma source ion implantation with superposed pulse

Diamond-like carbon (DLC) films were prepared on silicon wafer substrate by plasma source ion implantation with superposed negative pulse. Methane and acetylene gases were used as working gases for plasma. A negative DC voltage and a negative pulse voltage were superposed and applied to the substrate holder. The DC voltage was changed in the range from 0 to −4 kV and the pulse voltage was changed from 0 to −18 kV. The surface of DLC films was very smooth. The deposition rate of DLC films increased with increasing in superposed DC bias voltage. Carbon ion implantation was confirmed for the DLC film deposited from methane plasma with high pulse voltage. I D/ I G ratios of Raman spectroscopy were around 1.5 independent on pulse voltage. The maximum hardness of 20.3 GPa was observed for the film prepared with high DC and high pulse voltage.

Effect of microwave power on diamond-like carbon films deposited using electron cyclotron resonance chemical vapor deposition

Diamond-like carbon (DLC) films have been deposited using electron cyclotron resonance chemical vapor deposition (ECR-CVD) under various microwave power conditions. Langmuir probe measurement and optical emission spectroscopy (OES) were used to characterize the ECR plasma, while the films were characterized using Raman and infrared (IR) spectroscopies, hardness and optical gap measurements. It was found that the ion density and all signal peaks in the optical emission (OE) spectra increased monotonously following the increase in microwave power. Raman spectra and optical gap measurements indicate that the films become more graphitic with lower content of sp 3 -hybridized carbon atoms as the microwave power was increased. IR and hardness measurements indicate a reduction in hydrogen content and decrease in hardness for the film produced at relatively high microwave powers. A deposition mechanism is described which involved the ion bombardment of film surfaces and hydrogen–surface interactions. The deposition rate of DLC film is correlated to the ion density and CH 3 density.

Engineering analysis of diamond-like carbon coated polymeric materials for biomedical applications.

Diamond-like carbon (DLC) films have received much attention recently owing to their properties, which are similar to diamond: hardness, thermal conductivity, corrosion resistance against chemicals, abrasion resistance, good biocompatibility, and uniform flat surface. Furthermore, DLC films can be deposited easily on many substrates for wide area coat at room temperature. DLC films were developed for applications as biomedical materials in blood contacting-devices (e.g., rotary blood pump) and showed good biocompatibility for these applications. In this study, we investigated the surface roughness by Atomic Force Microscopy (AFM) and Hi-vision camera, SEM for surface imaging. The DLC films were produced by radio frequency glow discharge plasma decomposed of hydrocarbon gas at room temperature and low pressure (53 Pa) on several kinds of polycarbonate substrates. For the evaluation of the relation between deposition rate and platelet adhesion that we investigated in a previous study, DLC films were deposited at the same methane pressure for several deposition times, and film thickness was investigated. In addition, the deposition rate of DLC films on polymeric substrates is similar to the deposition rate of those deposited on Si substrates. There were no significant differences in substrates' surface roughness that were coated by DLC films in different deposition rates (16-40 nm). The surface energy and the contact angle of the DLC films were investigated. The chemical bond of DLC films also was evaluated. The evaluation of surface properties by many methods and measurements and the relationship between the platelet adhesion and film thickness is discussed. Finally, the presented DLC films appear to be promising candidates for biomedical applications and merit investigation.

腐食防食小特集 ＲＦプラズマＣＶＤ法によるＤＬＣ膜の生成とその摩擦・摩耗特性

Hard diamond-like-carbon (DLC) films were deposited on silicon substrate by RF plasma CVD using methane as a reactant gas. Both CH4 concentration and RF power were varied to find out a better deposition condition to make DLC film harder, since DLC film will be applied to tribological use. The deposition condition of CH4: 100% and RF power: 300W was the best in this paper. The deposition rate of DLC film under the condition was 2.1μm/hr.Friction and wear experiments were conducted with a reciprocating friction and wear test apparatus. EDX and XPS were used to analyze the sliding surfaces. The DLC film deposited under the above condition was slid against several kinds of metals to investigate fundamental friction and wear properties. And the results were compared with those of silicon substrate and steel (S15C). DLC film coating extremely reduced friction and wear of silicon substrate slid against all metals used in this paper. DLC film showed very low friction and wear especially against Ti alloy (Ti-6Al-4V), pure Ti, and stainless steel (SUS304). These 3 kinds of metals have characteristic of causing seizure easily during sliding or machining. The above mentioned results suggest that DLC film will have good tribological performance against metals that have high adhesive characteistic.