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Book Characterization of Diamond like Carbon Films Produced by Pulsed Laser Depostition

Download or read book Characterization of Diamond like Carbon Films Produced by Pulsed Laser Depostition written by Hideki Minami and published by . This book was released on 1999 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis and Characterization of Diamond like Carbon Thin Films for Biomedical Applications

Download or read book Synthesis and Characterization of Diamond like Carbon Thin Films for Biomedical Applications written by Russell Lee Leonard and published by . This book was released on 2010 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diamond-like carbon (DLC) thin films were produced by pulsed laser deposition (PLD) on silicon, fused silica, and silicon nitride substrates. The films produced were either undoped, made using a pure graphite target, or doped, using multi-component targets made from a combination of graphite and silicon, silicon nitride, titanium dioxide, or silicon monoxide. These films were evaluated for their potential use in biomedical applications, including coatings for artificial joints, heart stents, and bronchoscopes. The films were characterized by Raman spectroscopy, atomic force microscopy, ball-on-flat tribometry, contact angle measurements, and spectrophotometry. Film thickness was determined by optical profilometry. Film adhesion was checked by soaking the films in simulated body fluid (SBF) and monitoring the quality of the film surface at varying time intervals using an optical microscope. DLC coatings were produced with a root mean square surface roughness of less than 1 nm and a 0.08 lubricated coefficient of friction. Contact angles of water on the undoped films varied with deposition conditions, ranging from 65 to 88 degrees. Contact angles as low as 25 degrees were achieved by incorporating silicon monoxide dopant. DLC coatings were produced on fused silica having high transparency and showing no delamination after forty-three weeks of immersion in SBF. These results indicate that these films have potential as biomedical coatings.

Book Characterization of Amorphous Carbon Films Grown by Pulsed laser Deposition

Download or read book Characterization of Amorphous Carbon Films Grown by Pulsed laser Deposition written by and published by . This book was released on 1998 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Amorphous carbon (a-C) films grow via energetic processes such as pulsed-laser deposition (PLD). The cold-cathode electron emission properties of a-C are promising for flat-panel display and vacuum microelectronics technologies. These ultrahard films consist of a mixture of 3-fold and 4-fold coordinated carbon atoms, resulting in an amorphous material with diamond-like properties. The authors study the structures of a-C films grown at room temperature as a function of PLD energetics using x-ray reflectivity, Raman spectroscopy, high-resolution transmission electron microscopy, and Rutherford backscattering spectrometry. While an understanding of the electron emission mechanism in a-C films remains elusive, the onset of emission is typically preceded by conditioning where the material is stressed by an applied electric field. To simulate conditioning and assess its effect, the authors use the spatially-localized field and current of a scanning tunneling microscope tip. Scanning force microscopy shows that conditioning alters surface morphology and electronic structure. Spatially-resolved electron energy loss spectroscopy indicates that the predominant bonding configuration changes from predominantly 4-fold to 3-fold coordination.

Book Nanostructural Characterization of Amorphous Diamondlike Carbon Films

Download or read book Nanostructural Characterization of Amorphous Diamondlike Carbon Films written by and published by . This book was released on 2000 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanostructural characterization of amorphous diamondlike carbon (a-C) films grown on silicon using pulsed-laser deposition (PLD) is correlated to both growth energetic and film thickness. Raman spectroscopy and x-ray reflectivity probe both the topological nature of 3- and 4-fold coordinated carbon atom bonding and the topographical clustering of their distributions within a given film. In general, increasing the energetic of PLD growth results in films becoming more ''diamondlike'', i.e. increasing mass density and decreasing optical absorbance. However, these same properties decrease appreciably with thickness. The topology of carbon atom bonding is different for material near the substrate interface compared to material within the bulk portion of an a-C film. A simple model balancing the energy of residual stress and the free energies of resulting carbon topologies is proposed to provide an explanation of the evolution of topographical bonding clusters in a growing a-C film.

Book Pulsed Laser Deposited Amorphous Diamond and Related Materials

Download or read book Pulsed Laser Deposited Amorphous Diamond and Related Materials written by and published by . This book was released on 1999 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis and Characterization of Diamond like Carbon Coatings Deposited by Plasma Source Ion Implantation and Conventional Ion Beam Assisted Deposition Processes

Download or read book Synthesis and Characterization of Diamond like Carbon Coatings Deposited by Plasma Source Ion Implantation and Conventional Ion Beam Assisted Deposition Processes written by Brian M. Stout and published by . This book was released on 1999 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diamond-like carbon coatings produced by Plasma Source Ion Implantation (PSII) and beamline Ion Beam Assisted Deposition (IBAD) were synthesized and studied. Gas pressure and electrical current were used as variables to design four independent PSII test sets. Beamline IBAD samples were produced with a pre-optimized set of parameters. Profilometry measurements showed the films to have thicknesses between 1.44 +/- 09 and 1.64 +/- 04 microns and to possess very low roughness averages, ranging from 14 +/- 3 to 28 +/- 3 nm, which correlate with substrate surface roughness. Atomic Force Microscopy revealed that diamond-like carbon crystal sizes varied significantly with chamber pressure. Crystals were generally spherical in shape suggesting that films were highly amorphous. Microhardness and nanohardness test results showed the hardest films to be greater than 3 times the hardness of untreated steel. The elastic modulus of the films, measured during the nanohardness test, was directly related to film hardness. Fretting wear and Pin-on-Disk tests were performed to quantitatively assess the ability of films to resist wear. Fretting wear tests showed a dramatic decrease in friction for diamond-like carbon films with friction levels ranging from 10% to 30% of that of untreated steel. Pin-on-Disk tests revealed a significant improvement in wear resistance prior to stylus penetration into the substrate.

Book Pulsed Laser Deposition of Diamond like Carbon Films

Download or read book Pulsed Laser Deposition of Diamond like Carbon Films written by Deborah Lynn Thebert-Peeler and published by . This book was released on 1992 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Tribology of Diamond like Carbon Films

Download or read book Tribology of Diamond like Carbon Films written by Christophe Donnet and published by Springer Science & Business Media. This book was released on 2007-12-06 with total page 673 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights some of the most important structural, chemical, mechanical and tribological characteristics of DLC films. It is particularly dedicated to the fundamental tribological issues that impact the performance and durability of these coatings. The book provides reliable and up-to-date information on available industrial DLC coatings and includes clear definitions and descriptions of various DLC films and their properties.

Book Characterization of Carbon Nitride Films Produced by Pulsed Laser Deposition

Download or read book Characterization of Carbon Nitride Films Produced by Pulsed Laser Deposition written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon Nitride (CN[sub x]) films have been grown by ion-assisted pulsed-laser deposition (IAPLD). Graphite targets were laser ablated while bombarding the substrate with ions from a broad-beam Kaufman-type ion source. Ion voltage, current density, substrate temperature, and feed gas composition (N[sub 2] in Ar) were varied. Resultant films were characterized by Raman. Fourier transform infrared (FTIR), and Rutherford back scattering (RBS) spectroscopy. Samples with[approximately] 30% N/C ratio have been fabricated. The corresponding Raman and FTIR spectra indicate that nitrogen is incorporated into the samples by insertion into sp[sup 2]-bonded structures. A low level of C[identical-to]N triple bonds is also found. As the ion current and voltage are increased with a pure Ar ion beam, Raman peaks associated with nanocrystalline graphite appear in the spectra. Adding low levels of nitrogen to the ion beam first reduces the Raman intensity in the vicinity of the graphite disorder peak without adding detectable amounts of nitrogen to the films (as measured by RBS). At higher nitrogen levels in the ion beam, significant amounts of nitrogen are incorporated into the samples, and the magnitude of the''disorder'' peak increases. By increasing the temperature of the substrate during deposition, the broad peak due mainly to sp[sup 2]-bonded C-N in the FTIR spectra is shifted to lower wavenumber. This could be interpreted as evidence of single-bonded C-N; however, it is more likely that the character of the sp[sup 2] bonding is changing.

Book Diamond like Carbon Films

Download or read book Diamond like Carbon Films written by Yuto S. Tanaka and published by Nova Biomedical Books. This book was released on 2012-02 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents current research from across the globe in the study of diamond-like carbon films. Topics discussed include the peculiarities of ion-beam synthesis of carbon-based phases; electron field emission properties of non-metal and metal doped diamond like carbon; internal stress and its reduction of hydrogenated diamond-like carbon thin films deposited by plasma CVD methods; incorporating crystalline diamond particles in diamond-like carbon films to improve their properties and diamond-like carbon films applied as an alignment layer for LCDs.

Book Pulsed Laser Deposition of Amorphous Diamond Like Carbon Films with ArF 193 Nm Excimer Laser

Download or read book Pulsed Laser Deposition of Amorphous Diamond Like Carbon Films with ArF 193 Nm Excimer Laser written by and published by . This book was released on 1992 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have deposited hydrogen-free diamond-like amorphous carbon (amorphous diamond) films by ArF (193 nm) pulsed laser ablation of graphite. The deposition process is performed with the laser power density of only 5x10(8) W/cm2 at room temperature without any auxiliary energy source incorporation. The resulting films possess remarkable physical, optical and mechanical properties which are close to those of diamond and distinct from the graphite target used. The films have a mechanical hardness up to 38 GPa, an optical energy band gap of 2.6 eV and excellent thermal stability. Analysis of electron energy loss spectroscopy reveals the domination of diamond-type tetrahedral bonding structure in the films with the Sp3 bond fraction over 95%. Compared to other reported results of pulsed laser deposited diamond-like carbon films, our experimental results confirm that the laser wavelength or photon energy plays a crucial role in controlling the properties of the pulsed laser deposited diamond-like carbon films.