Effect of DC self-bias on the adhesion of diamond-like carbon deposited on metal tracks by RF-PECVD

In this work, we investigate the use of high power impulse magnetron sputtering (HiPIMS) for the deposition of micrometer thick diamond like carbon (DLC) coatings on Si and steel substrates. The adhesion on both types of substrates is ensured with a simple Ti interlayer, while the energy of impinging ions is adjusted by using RF (Radio Frequency) biasing on the substrate at −100 V DC self-bias. Addition of acetylene to the working Ar+Ne atmosphere is investigated as an alternative to Ar sputtering, to improve process stability and coatings quality. Peak current is maintained constant, providing reliable comparison between different deposition conditions used in this study. The main advantages of adding acetylene to the Ar+Ne gas mixture are an increase of deposition rate by a factor of 2, when comparing to the Ar+Ne process. Moreover, a decrease of the number of surface defects, from ~40% surface defects coverage to ~1% is obtained, due to reduced arcing. The mechanical and tribological properties of the deposited DLC films remain comparable for all investigated gas compositions. Nanoindentation hardness of all coatings is in the range of 25 to 30 GPa, friction coefficient is between 0.05 and 0.1 and wear rate is in the range of 0.47 to 0.77 × 10−6 mm3 N−1m−1.

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Diamond-like Carbon Film Deposition on an Artificial Heart Blood Pump Using a Flexible Type Electrode with r.f. Plasma CVD Processing

MRS Proceedings ◽

10.1557/proc-0956-j09-25 ◽

2006 ◽

Vol 956 ◽

Author(s):

Kazuya Kanasugi ◽

Yasuharu Ohgoe ◽

Katsuya Tsuchimoto ◽

Keisuke Sato ◽

Kenji K. Hirakuri ◽

...

Keyword(s):

Artificial Heart ◽

Carbon Film ◽

Film Coating ◽

Film Structure ◽

Film Deposition ◽

Blood Pump ◽

Diamond Like Carbon ◽

Dlc Film ◽

Self Bias ◽

Heart Blood

ABSTRACTDiamond-like carbon (DLC) film was deposited uniformly on an irregular structure such as a polyurethane artificial heart blood pump using a special 3-dimensional type electrode. Process of applying the DLC film coating is accomplished by inserting a large number of small metallic balls (φ0.8 mm chromium balls). It is then possible to adjust the shape of the electrode in such a way that the DLC film coating can be applied to the irregular surface of the artificial heart. In investigating the availability of the electrode, under helium (He) plasma, the plasma states were measured using double probe analysis. Lateral profiles of the electron temperature were higher in the centre and decreased towards the edges of the electrode. On the other hand, the plasma density profiles were lower in the centre part than at the edges. The electrode kept ion sheath on the artificial heart blood pump's surface at self-bias voltage uniformly. The results were that the DLC film was deposited completely on the artificial heart blood pump at the film thickness of approximately 350 - 380 nm. Additionally the film structure was uniform.

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Substrate Effect on the Diamond-Like Carbon Films Synthesized by RF Plasma Enhanced Chemical Vapor Deposition

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.3574 ◽

2007 ◽

Vol 539-543 ◽

pp. 3574-3579 ◽

Cited By ~ 1

Author(s):

S.S. Tzeng ◽

Wei Min Wu ◽

J.S. Hsu

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Carbon Films ◽

The Self ◽

Rf Plasma ◽

Diamond Like Carbon ◽

Working Pressure ◽

Glass Substrates ◽

Self Bias

Diamond-like carbon (DLC) films were synthesized by RF plasma enhanced chemical vapor deposition using methane as carbon source. Effect of substrate on the growth of DLC films was investigated by using four different substrate materials, silicon wafer (100), glass, flat-polished and mirror-polished alumina. The carbon films were deposited at four different self-bias voltages (-157 V, -403 V, -500 V and -590 V) by changing the plasma power under fixed flow rate and working pressure. Raman analyses indicated that DLC films were deposited on silicon and glass substrates at the self-bias -403 V ~ -590 V, and polymer-like carbon films were obtained at -157 V. For the alumina substrates, different Raman results were observed for flat-polished and mirror-polished alumina substrates. The hardness of DLC films, deposited on silicon and glass substrates at the self-bias -403 V ~ -590 V, was within 16~20 GPa using nanoindentation technique.

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Diamond-Like Carbon Deposition for Tribological Applications at Los Alamos National Laboratory

MRS Proceedings ◽

10.1557/proc-383-411 ◽

1995 ◽

Vol 383 ◽

Cited By ~ 1

Author(s):

K. C. Walter ◽

M. Nastasi ◽

H. Kung ◽

P. Kodali ◽

C. Munson ◽

...

Keyword(s):

Carbon Deposition ◽

Tribological Behavior ◽

National Laboratory ◽

Rf Plasma ◽

Diamond Like Carbon ◽

Alamos National Laboratory ◽

Los Alamos National Laboratory ◽

Self Bias ◽

Coating Characteristics ◽

Deposition Techniques

ABSTRACTDiamond-like carbon (DLC) films have been deposited on silicon using two deposition techniques. Both deposition techniques used acetylene (C2H2) plasmas as the carbon/hydrogen source. One technique, that is relatively well known, employs an rf-plasma with an associated self-bias on the substrate. DLC films have also been deposited using a pulsed-bias method. Coatings of various thickness have been deposited using both deposition methods, and various combinations of gas pressure and bias. Coating characteristics, such as composition, density, and sp3 content, of selected films will be presented. For each deposition technique, the correlation between coating characteristics, mechanical properties and tribological behavior is presented.

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Effect of target self-bias voltage on the mechanical properties of diamond-like carbon films deposited by RF magnetron sputtering

Thin Solid Films ◽

10.1016/j.tsf.2004.04.006 ◽

2004 ◽

Vol 468 (1-2) ◽

pp. 149-154 ◽

Cited By ~ 31

Author(s):

S. Chowdhury ◽

M.T. Laugier ◽

I.Z. Rahman

Keyword(s):

Mechanical Properties ◽

Magnetron Sputtering ◽

Bias Voltage ◽

Rf Magnetron Sputtering ◽

Carbon Films ◽

Diamond Like Carbon ◽

Self Bias

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Electron energy loss spectroscopy of diamond-like carbon thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130997 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1272-1273

Author(s):

J. Kulik ◽

Y. Lifshitz ◽

G.D. Lempert ◽

S. Rotter ◽

J.W. Rabalais ◽

...

Keyword(s):

Thin Films ◽

Energy Loss ◽

Electron Energy ◽

Ion Beam ◽

Diamond Like Carbon ◽

Ion Beam Deposition ◽

Chemistry Research ◽

Carbon Thin Films ◽

Electron Energy Loss ◽

Beam Deposition

Carbon thin films with diamond-like properties have generated significant interest in condensed matter science in recent years. Their extreme hardness combined with insulating electronic characteristics and high thermal conductivity make them attractive for a variety of uses including abrasion resistant coatings and applications in electronic devices. Understanding the growth and structure of such films is therefore of technological interest as well as a goal of basic physics and chemistry research. Recent investigations have demonstrated the usefulness of energetic ion beam deposition in the preparation of such films. We have begun an electron microscopy investigation into the microstructure and electron energy loss spectra of diamond like carbon thin films prepared by energetic ion beam deposition.The carbon films were deposited using the MEIRA ion beam facility at the Soreq Nuclear Research Center in Yavne, Israel. Mass selected C+ beams in the range 50 to 300 eV were directed onto Si {100} which had been etched with HF prior to deposition.

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Chemical structure of diamond-like carbon thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017668x ◽

1990 ◽

Vol 48 (4) ◽

pp. 710-711

Author(s):

N.-H. Cho ◽

K.M. Krishnan ◽

D.B. Bogy

Keyword(s):

Electrical Resistivity ◽

Chemical Structure ◽

Diamond Like Carbon ◽

Chemical Structures ◽

Sputtering Power ◽

Data Aquisition ◽

Equilibrium Phases ◽

Electron Energy Loss ◽

Power Densities ◽

Preparation Techniques

Diamond-like carbon (DLC) films have attracted much attention due to their useful properties and applications. These properties are quite variable depending on film preparation techniques and conditions, DLC is a metastable state formed from highly non-equilibrium phases during the condensation of ionized particles. The nature of the films is therefore strongly dependent on their particular chemical structures. In this study, electron energy loss spectroscopy (EELS) was used to investigate how the chemical bonding configurations of DLC films vary as a function of sputtering power densities. The electrical resistivity of the films was determined, and related to their chemical structure.DLC films with a thickness of about 300Å were prepared at 0.1, 1.1, 2.1, and 10.0 watts/cm2, respectively, on NaCl substrates by d.c. magnetron sputtering. EEL spectra were obtained from diamond, graphite, and the films using a JEOL 200 CX electron microscope operating at 200 kV. A Gatan parallel EEL spectrometer and a Kevex data aquisition system were used to analyze the energy distribution of transmitted electrons. The electrical resistivity of the films was measured by the four point probe method.

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