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1.
Preparation of super-hard coatings by pulsed laser deposition 总被引:1,自引:0,他引:1
G. Reisse S. Weissmantel D. Rost 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1275-1278
Amorphous diamond-like carbon (DLC) films and nanocrystalline cubic boron nitride (c-BN) films were prepared by pulsed laser deposition. DLC films with 80 to 85% sp3 bonds prepared at a laser fluence above 6 J/cm2 and a substrate temperature below 100 °C show high compressive stresses in the range of 8 to 10 GPa. Those stresses can be completely removed by means of pulsed laser annealing, allowing the preparation of DLC films with several-micrometre thickness. c-BN films were prepared with additional ion-beam bombardment at a substrate temperature of 250 °C. The properties of DLC and c-BN films deposited at high growth rates up to 100 nm/min are presented . PACS 81.15.Fg; 68.60.Bs: 62.40.+i 相似文献
2.
K. Sreejith 《Applied Surface Science》2005,252(2):296-302
Attempt has been made to deposit diamond like carbon (DLC) films from ethanol through electrodeposition at low voltages (80-300 V) at 1 mm interelectrode separation. The films were characterized by atomic force microscopy (AFM), Scanning electron microscopy (SEM), Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy and Auger electron Spectroscopy (AES). AFM investigations revealed the grain sizes are of tens of nanometers. The films were found to be continuous, smooth and close packed. Presence of peaks at 2958, 2929 and 2869 cm−1 in FTIR spectrum indicates the bonding states to be of predominantly sp3 type (C-H). Raman spectroscopy analysis revealed two broad bands at ∼1350 and ∼1570 cm−1. The downshift of the G-band of graphite is indicative of presence of DLC. Analysis of the Raman spectra for the samples revealed an improvement in the film quality with increase in the voltage. Micro Raman investigations indicate the formation of diamond phase at the deposition potential of 80 V. The sp2 contents the films calculated from Auger electron spectra were calculated and were found to be 31, 19 and 7.8% for the samples prepared at 80, 150 and 300 V, respectively. A tentative mechanism for the formation of DLC has been proposed. These results indicate the possibility of deposition of DLC at low voltage. 相似文献
3.
Zhenyu Zhang Fengwei Huo Zhenyuan Jia Dongming Guo Zhuji Jin Renke Kang 《Applied Surface Science》2008,254(22):7193-7197
A novel kind of La2O3 doped diamond-like carbon (DLC) films with thickness of 100-120 nm were deposited by unbalanced magnetron sputtering. Raman spectra and photoluminescence properties were measured by Raman spectrometer operated by 325 nm He-Cd laser and 514 nm Ar+ laser, respectively. The intensities of Raman spectra and photoluminescence are higher than those of pure DLC films. The La2O3 doped DLC films have the potential promising for the application of solar cell coatings. 相似文献
4.
Optical and Electrical Properties Evolution of Diamond-Like Carbon Thin Films with Deposition Temperature 下载免费PDF全文
Optical and electrical properties of diamond-like carbon (DLC) films deposited by pulsed laser ablation of graphite target at different substrate temperatures are reported. By varying the deposition temperature from 400 to 25℃, the film optical transparency and electrical resistivity increase severely. Most importantly, the transparency and resistivity properties of the DLC films can be tailored to approaching diamond by adjusting the deposition temperature, which is critical to many applications. DLC films deposited at low temperatures show excellent optical transmittance and high resistivity. Over the same temperature regime an increase of the spa bonded C content is observed using visible Raman spectroscopy, which is responsible for the enhanced transparency and resistivity properties. 相似文献
5.
Jisheng Zhang 《Applied Surface Science》2008,254(13):3896-3901
Diamond-like carbon (DLC) films were prepared on silicon substrates by liquid phase electrodeposition from a mixture of acetonitrile and deionized water. The deposition voltage was clearly reduced owing to the presence of deionized water in the electrolyte by changing the basic properties (dielectric constant and dipole moment) of the electrolyte. Raman spectra reveal that the ratio of sp3/sp2 in the DLC films is related to the concentration of acetonitrile. The surface roughness and grain morphology determined by atomic force microscopy are also influenced by the concentration of the acetonitrile. The UMT-2 universal micro-tribometer was used to test the friction properties of the DLC films obtained from electrolytes with different concentration. The results convey that the DLC film prepared from the electrolyte containing 10 vol.% acetonitrile has the better surface morphology and friction behavior comparing with the other. In addition the growth mechanism of the film was also discussed. 相似文献
6.
Timothy T. Ho Manisha Gupta Fatema Rezwana Chowdhury Zhijiang Chen Ying Yin Tsui 《Applied physics. B, Lasers and optics》2013,113(3):429-436
Here, we report the fabrication of diamond-like carbon (DLC) thin films using pulsed laser deposition (PLD). PLD is a well-established technique for deposition of high-quality DLC thin films. Carbon tape target was ablated using a KrF (248 nm, 25 ns, 20 Hz) excimer laser to deposit DLC films on soap-coated substrates. A laser fluence between 8.5 and 14 J/cm2 and a target to substrate distance of 10 cm was used. These films were then released from substrates to obtain freestanding DLC thin foils. Foil thicknesses from 20 to 200 nm were deposited using this technique to obtain freestanding targets of up to 1-inch square area. Typically, 100-nm-thick freestanding DLC films were characterized using different techniques such as AFM, XPS, and nano-indentation. AFM was used to obtain the film surface roughness of 9 nm rms of the released film. XPS was utilized to obtain 74 % sp2, 23 % sp3, and 3 % C–O bond components. Nano-indentation was used to characterize the film hardness of 10 GPa and Young’s modulus of 110 GPa. Damage threshold properties of the DLC foils were studied (1,064 nm, 6 ns) and found to be 7 × 1010 W/cm2 peak intensity for our best ultrathin DLC foils. 相似文献
7.
Diamond-like carbon (DLC) films deposited on different substrates by plasma enhanced chemical vapour deposition were investigated. Bonding states and film quality were characterized by FT-IR spectroscopy. The influence of the power of plasma and the deposition time on the sp2/sp3 ratio as well as the concentration of CHn bonds was studied. The influence of sp2/sp3 ratio on the formation process of conducting channels in diamond-like carbon films as a result of electrical breakdown was determined. Reproducible increase of diamond-like carbon film conductivity, with initial sp2/sp3 ratio larger than 0.16, was observed after electrical breakdown. 相似文献
8.
Diamond-like carbon (DLC) films were deposited on Si (1 0 0) substrate using a low energy (219 J) repetitive (1 Hz) miniature plasma focus device. DLC thin film samples were deposited using 10, 20, 50, 100 and 200 focus shots with hydrogen as filling gas at 0.25 mbar. The deposited samples were analyzed by XRD, Raman Spectroscopy, SEM and XPS. XRD results exhibited the diffraction peaks related to SiO2, carbon and SiC. Raman studies verified the formation amorphous carbon with D and G peaks. Corresponding variation in the line width (FWHM) of the D and G positions along with change in intensity ratio (ID/IG) in DLC films was investigated as a function of number of deposition shots. XPS confirmed the formation sp2 (graphite like) and sp3 (diamond like) carbon. The cross-sectional SEM images establish the 220 W repetitive miniature plasma focus device as the high deposition rate facility for DLC with average deposition rate of about 250 nm/min. 相似文献
9.
Diamond-like carbon (DLC) is an attractive biomedical material due to its high inertness and excellent mechanical properties. In this study, DLC films were fabricated on Ti6Al4V and Si(1 0 0) substrates at room temperature by pulsed vacuum arc plasma deposition. By changing the argon flow from 0 to 13 sccm during deposition, the effects of argon flow on the characteristics of the DLC films were systematically examined to correlate to the blood compatibility. The microstructure and mechanical properties of the films were investigated using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) surface analysis, a nano-indenter and pin-on-disk tribometer. The blood compatibility of the films was evaluated using in vitro platelet adhesion investigation, and the quantity and morphology of the adherent platelets was investigated employing optical microscopy and scanning electron microscopy.The Raman spectroscopy results showed a decreasing sp3 fraction (an increasing trend in ID/IG ratio) with increasing argon flow from 0 to 13 sccm. The sp3:sp2 ratio of the films was evaluated from the deconvoluted XPS spectra. We found that the sp3 fraction decreased as the argon flow was increased from 0 to 13 sccm, which is consistent with the results of the Raman spectra. The mechanical properties results confirmed the decreasing sp3 content with increasing argon flow. The Raman D-band to G-band intensity ratio increased and the platelet adhesion behavior became better with higher flow. This implies that the blood compatibility of the DLC films is influenced by the sp3:sp2 ratio. DLC films deposited on titanium alloys have high wear resistance, low friction and good adhesion. 相似文献
10.
采用脉冲激光气相沉积(PLD)法,研究了氢气压强对非晶CH薄膜性能的影响。原子力显微镜图和白光干涉图显示,薄膜表面平整致密,随着氢气压强增大,粗糙度变大。拉曼光谱分析表明,氢气压强增加,G峰和D峰位置都在向高波数方向移动。傅里叶变换红外光谱分析显示,薄膜中存在sp3—CH2和sp2—CH等基团。最后,采用PLD漂浮法在最优参数氢气压强为0.3 Pa下,成功制备了不同厚度(100~300 nm)、满足一定力学强度、无明显宏观缺陷的自支撑CH薄膜。 相似文献
11.
Diamond-like carbon (DLC) films were fabricated by pulsed laser ablation of a liquid target. During deposition process the growing films were exited by a laser beam irradiation. The films were deposited onto the fused silica using 248 nm KrF eximer laser at room temperature and 10−3 mbar pressure. Film irradiation was carried out by the same KrF laser operating periodically between the deposition and excitation regimes. Deposited DLC films were characterized by Raman scattering spectroscopy. The results obtained suggested that laser irradiation intensity has noticeable influence on the structure and hybridization of carbon atoms deposited. For materials deposited at moderate irradiation intensities a very high and sharp peak appeared at 1332 cm−1, characteristic of diamond crystals. At higher irradiation intensities the graphitization of the amorphous films was observed. Thus, at optimal energy density the individual sp3-hybridized carbon phase was deposited inside the amorphous carbon structure. Surface morphology for DLC has been analyzed using atomic force microscopy (AFM) indicating that more regular diamond cluster formation at optimal additional laser illumination conditions (∼20 mJ per impulse) is possible. 相似文献
12.
D. Guo K. Cai L.-T. Li Y. Huang Z.-L. Gui 《Applied Physics A: Materials Science & Processing》2002,74(1):69-72
Diamond-like-carbon (DLC) films have been deposited on Si, aluminum and indium tin oxide-coated glass from several organic
solvents with pulse-modulated power. The films are characterized by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy.
XPS spectra show that the main composition of the films is carbon and Raman spectra show that the films are typical DLC films
and a high potential is preferable in the formation of sp
3-structure carbon. Comparing the results from different solvents and different substrates we deduce that the methyl group
of the solvents has a critical function in forming the DLC films. However, the formation process and the characters of the
films, such as appearance, resistivity and thickness, are mainly determined by the substrate. We may call this deposition
a substrate-controlled reaction.
Received: 31 May 2000 / Accepted: 9 January 2001 / Published online: 3 April 2001 相似文献
13.
Tomas Kocourek Miroslav Jelinek Vladimír Vorlíček Josef Zemek Tomáš Janča Věra Žížková Jiří Podlaha Cyril Popov 《Applied Physics A: Materials Science & Processing》2008,93(3):627-632
Textile blood vessels with a length of 30 cm were coated with amorphous diamond-like carbon (DLC) layers with thicknesses
up to 200 nm. The layers were created by pulsed laser deposition in vacuum or argon ambient. The percentage of sp3 carbon was evaluated using X-ray photoelectron spectroscopy, X-ray excited Auger electron spectroscopy and Raman spectroscopy.
Depending on the deposition conditions the sp3 content varied from ∼40% to 60%. The adhesion of the DLC layers to the textile vessels was checked. The preliminary biocompatibility
results from in vivo tests with sheep are also given. 相似文献
14.
S.S. Roy P. Papakonstantinou R. McCann J. McLaughlin A. Klini N. Papadogiannis 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1009-1014
The effect of nitrogen addition and laser fluence on the atomic structure of amorphous carbon films (a-C) synthesized by femtosecond pulsed laser deposition has been studied. The chemical bonding in the films was investigated by means of X-ray photoelectron (XPS) and Raman spectroscopies. XPS studies revealed a decrease in the sp3 bonded carbon sites and an associated increase in the N-sp2C bonding sites with increasing nitrogen content in the CNx films. An increase in laser fluence from 0.36 to 1.7 J/cm2 led to a rise in sp3C sites. These results were further confirmed by Raman spectroscopy. The ID/IG ratio increased monotonically and G line-width decreased with the increase of nitrogen content in the films indicating a rise in either the number or the size of the sp2 clusters. Furthermore a visible excitation wavelength dependence study established the resonant Raman process in a-C and CNx films. PACS 81.05.Uw; 81.15.Fg; 82.80 相似文献
15.
In order to improve the adherence of DLC films, interlayers of amorphous hydrogenated carbon (a-C:H) and titanium nitride (TiN) were deposited by means of the pulsed vacuum arc technique. Bilayers were obtained by using a carbon target of 99.98% of purity in mixtures of (Ar + CH4) and (Ar + H2) for producing a-C and DLC, respectively and a target of titanium of 99.999% in a mixture of (Ar + N2) for growing TiN. After the deposition, chemical and morphological differences between TiN/DLC and a-C:H/DLC bilayers grown on silicon and stainless steel 304 were studied using X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), and scanning probe microscopy (SPM) techniques. XPS analysis showed a difference in sp3/(sp2+sp3) bonds ratio for each bilayer, being 0.67 for TiN/DLC and 0.45 for a-C:H/DLC bilayers. sp3 and sp2 bonds were also observed by the FTIR technique. SPM images, in atomic force microscopy (AFM) and lateral force microscopy (LFM) modes were carried out for illustrating the comparison between TiN/DLC and a-C/DLC morphologic characteristics. Roughness and grain size were studied as a function of the H2 concentration for both bilayers. 相似文献
16.
Petr Písařík Miroslav Jelínek Karel Smetana Jr. Barbora Dvořánková Tomáš Kocourek Josef Zemek Dagmar Chvostová 《Applied Physics A: Materials Science & Processing》2013,112(1):143-148
Optical and biomedical properties of diamond-like carbon (DLC) films of various sp2, sp3 bonds were studied. The layers were prepared by pulsed laser deposition (PLD) for laser energy densities from 4 J?cm?2 to 14 J?cm?2. The percentage of sp2 and sp3 bonds was calculated using X-ray photoelectron spectroscopy (XPS). In dependence on density the films contained up to 70 % of sp3 bonds. Optical properties were measured using spectroscopic ellipsometry in region from 250 nm to 1000 nm (n=2.6–2.7; k=0.07–0.25) and by transmission measurement (from 200 nm to 1100 nm). The adhesion and growth of human fibroblasts and keratinocytes of DLC films were tested in vitro. 相似文献
17.
S. Rey F. Antoni B. Prevot E. Fogarassy J.C. Arnault J. Hommet F. Le Normand P. Boher 《Applied Physics A: Materials Science & Processing》2000,71(4):433-439
Diamond-like carbon (DLC) films have been grown on Si substrates at ambient temperature by the pulsed-laser ablation technique,
using pulses of different durations both in the nano- and picosecond ranges and at various energy fluences. The stability
of these films was investigated as a function of thermal anneals performed in UHV conditions up to 1273 K. Their physico-chemical
properties have been characterized by different techniques including X-ray photo-emission, Auger electron and electron-energy-loss
spectroscopies, Raman scattering, spectroscopic ellipsometry and atomic-force microscopy. The thermal stability of the films
has been demonstrated to be related to their initial structural (sp3/sp2 ratio) and chemical (contaminant) properties. DLC layers prepared under optimized conditions have been found to show a very
good thermal stability up to 900 K.
Received: 4 Jule 2000 / Accepted: 6 July 2000 / Published online: 6 September 2000 相似文献
18.
Neeraj Dwivedi Sushil Kumar Hitendra K. Malik C. Sreekumar Saurabh Dayal C.M.S. Rauthan O.S. Panwar 《Journal of Physics and Chemistry of Solids》2012,73(2):308-316
Copper containing diamond like carbon (Cu-DLC) thin films were deposited on various substrates at a base pressure of 1×10?3 Torr using a hybrid system involving DC-sputtering and radio frequency-plasma enhanced chemical vapor deposition (RF-PECVD) techniques. The compressive residual stresses of these films were found to be considerably lower, varying between 0.7 and 0.94 GPa and Cu incorporation in these films improve their conductivity significantly. Their structural properties were studied by Raman spectroscopy, atomic force microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction techniques that clearly revealed the presence of Cu in the DLC structure. Raman analysis yields that Cu incorporation in DLC enhances the graphite-like sp2 bonding. However, the sp2 bonding was found to continuously reduce with the increasing C2H2 gas pressure, this may be due to reduction of Cu nanocrystal at the higher pressure. FTIR results inferred various bonding states of carbon with carbon, hydrogen and oxygen. In addition, hydrogen content and sp3 and sp2 fractions in different Cu-DLC films were also estimated by FTIR spectra and were correlated with stress, electrical, optical and nano-mechanical properties of Cu-DLC films. The effect of indentation load (4–10 mN) on nano-mechanical properties of these films was also explored. 相似文献
19.