Resonant Raman characterisation of ultra-thin nano-protective carbon layers for magnetic storage devices

Gradowski, M. von; Ferrari, Andrea C.; Ohr, Ralph; Jacoby, B.; Hilgers, H.; Schneider, H.-H.; Adrian, H.

doi:10.1016/s0257-8972(03)00602-9

Cited by 38 publications

(28 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Obviously, an intensive D band and a weak shoulder G band appeared, the I D /I G ratio of the as-deposited film was about 2.5 from the curve-fitted Raman spectrum. According to Ref [22], the as-deposited carbon films contained large fraction of sp 2 sites, indicating the graphite-like structure for the as-deposited films. In addition, the comparative wider FWHM of G band indicated a higher bond length and bond angle disorder [25].…”

Section: Microstructure Of Nanocomposite Glc Filmsmentioning

confidence: 90%

“…The G band and the D band are characteristics of carbon-based materials, while the G band position around 1560 cm -1 originated from optical zone center vibrations (E2g mode) of all the pairs of sp 2 C atoms in aromatic rings and olefinic chains, and the D band peak at 1350 cm -1 originated from the breathing modes of sp 2 atoms in clusters of sixfold aromatic rings [22,23]. Based on the variation of the two bands, Raman spectrum can provide many information about the microstructure, such as the Full-Width Half-Maximum (FWHM), the position of the D and G bands, the intensity of the I D /I G ratio, etc., and the estimation of the sp 3 -and sp 2 -hybridized carbon bonds can be thus indirectly drawn from the variation degree of the G and the D bands [24].…”

Section: Microstructure Of Nanocomposite Glc Filmsmentioning

confidence: 99%

See 1 more Smart Citation

Nanocomposite Microstructure and Environment Self-Adapted Tribological Properties of Highly Hard Graphite-Like Film

Wang

et al. 2010

Tribol Lett

View full text Add to dashboard Cite

Graphite-like carbon (GLC) nanocomposite films were fabricated by DC magnetron sputtering using high pure graphite target at ambient temperature. Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) investigation showed that the as-deposited GLC films have high concentration of sp 2 -hybridized carbon. High-resolution transmission electron microscopy (HRTEM) images and selected area diffraction patterns (SADP) indicated a complex nanocomposite microstructure of the GLC films. As well as nanocrystalline graphite, a face-center cubic (fcc) diamond with a grain size in the range of 3-8 nm were dispersed in the amorphous carbon matrix inhomogenously and integrally. The nanocomposite GLC film had high hardness of 23 GPa, which was attributed to the mutual strengthening effect of nanoparticles and amorphous matrix. More importantly, the as-deposited nanocomposite GLC film exhibited excellent self-adapted tribological properties in different environments of ambient air, different relative humidity and water. The friction coefficients were 0.053 in ambient air and 0.046 in distilled water, while specific wear rates were 4.5 9 10 -16 m 3 N -1 m -1 and 1.6 9 10 -16 m 3 N -1 m -1 , respectively. The friction regimes and mechanisms in different environments were elaborated. This film is foreseen to high potential in protecting and solid lubricating material in humidity or water environment.

show abstract

Section: Microstructure Of Nanocomposite Glc Filmsmentioning

confidence: 90%

Section: Microstructure Of Nanocomposite Glc Filmsmentioning

confidence: 99%

Nanocomposite Microstructure and Environment Self-Adapted Tribological Properties of Highly Hard Graphite-Like Film

Wang

et al. 2010

Tribol Lett

View full text Add to dashboard Cite

show abstract

“…In order to analyze the Raman spectra, we adopte Gaussians function to fit these spectra which were all subtracted with baseline before fitting. In general, The D-and G-bands shown in the spectra are due to the inelastic scattering of sp 2 sites [11][12][13] . The variation in the position and the shape of the two peaks are due to the structural changes, formation of disorder, aromatic rings, micrographite, etc [11][12][13][14] .…”

mentioning

confidence: 99%

“…In general, The D-and G-bands shown in the spectra are due to the inelastic scattering of sp 2 sites [11][12][13] . The variation in the position and the shape of the two peaks are due to the structural changes, formation of disorder, aromatic rings, micrographite, etc [11][12][13][14] . The G peak is a bond stretching of all pairs of sp 2 sites arranged in olefin chains or aromatic rings [15][16][17] .…”

mentioning

confidence: 99%

“…The G peak is a bond stretching of all pairs of sp 2 sites arranged in olefin chains or aromatic rings [15][16][17] . The D peak is a breathing vibration of a six-fold aromatic ring, associated with disorder [11,12,15] . Low sp 2 contents in the films are expressed by a low intensity ratio I D /I G , whereas a higher ratio points to a larger clustering of sp 2 sites in volume or number [11][12][13][14][15][16] .…”

mentioning

confidence: 99%

See 1 more Smart Citation

Effect of nitrogen pressure on optical properties and microstructure of diamond-like carbon films grown by pulsed laser deposition

Ding

Liu

Kong

2009

Optoelectron. Lett.

View full text Add to dashboard Cite

The effect of nitrogen pressure on optical properties of hydrogen-free diamond-like carbon (DLC) films deposited by pulsed laser ablation graphite in different background pressures of nitrogen is reported. By varying nitrogen pressures from 0.05 to 15.00 Pa, the photoluminescence is gradually increased and optical transmittance is gradually decreased. Atomic force microscopy (AFM) is used to observe the surface morphology of the DLC films. The results indicate that the surface becomes unsmoothed and there are some globose particles on the films surface with the rise of nitrogen pressures. The microstructure of the films is characterized using Raman spectroscopy.Diamond-like carbon (DLC) is a very attractive material due to its unique properties, which resembles diamond while the synthetic conditions are easier compared with diamond [1][2][3][4] . Many physical and chemical methods have been adopted to synthesize DLC [4][5][6][7][8] . But most chemical vapor deposition (CVD) methods generate hydrogenated amorphous carbon which is not stable when temperature is high [9,10] . In addition, CVD techniques usually need high substrate temperature ( 800 o C) which is not favorable when the substrate is thermally sensitive. The pulsed laser deposition (PLD) has the unique ability to synthesize hydrogen-free DLC films at low deposition temperature. The deposition parameters (e.g. temperature, ambient gas pressure, laser intensity, etc) are important for PLD system. A wide range of DLC films growth conditions has been reported in the literature for the past several decades but there are few reports of nitrogen circumstances. In this letter, we report DLC films grown at different background pressures of nitrogen by PLD. DLC films are deposited by pulsed laser ablation of a high pure (99.999%) graphite target using a Tuilaser ThinFilms Star 20 excimer laser operating at 248 nm. The laser beam with energy of 120 mJ is focused with a spherical lens onto rotating target at an incidence angle of 45°. The repetition rate of laser pulses is set to 10 Hz. Before depositting the films, the quartz substrates are ultrasonically cleaned with acetone and alcohol for 10 minutes separately, then rinsed repeatedly in de-ionized water and blew dry and then placed in growth chamber immediately. The growth chamber is evacuated using a turbomolecular pump to 5.0 10 -6 Pa, and then backfilled with nitrogen to the required pressure. The DLC films are grown at different background nitrogen pressure ranging from 0.05 Pa to 15.00 Pa. The pulsed laser shots are maintained in the range of 10000-20000, in order to maintain the same film thickness for each deposition. The target to substrate distance is fixed at 60 mm. The films are deposited onto a rotating substrate which is wheeled by a motor in order to obtain uniform thin films. In order to avoid target drilling, the target is also rotated to provide each laser pulse a fresh target surface. Before deposition, the substrates are argon ion etched for residual impurities for 10 minutes.The microstruct...

show abstract

Raman Spectroscopy of Carbon Based Films – Spectra Interpretation and Selected Applications

Kahn

Waldhauser

2010

Berg Huettenmaenn Monatsh

View full text Add to dashboard Cite

Resonant Raman characterisation of ultra-thin nano-protective carbon layers for magnetic storage devices

Cited by 38 publications

References 16 publications

Nanocomposite Microstructure and Environment Self-Adapted Tribological Properties of Highly Hard Graphite-Like Film

Nanocomposite Microstructure and Environment Self-Adapted Tribological Properties of Highly Hard Graphite-Like Film

Effect of nitrogen pressure on optical properties and microstructure of diamond-like carbon films grown by pulsed laser deposition

Raman Spectroscopy of Carbon Based Films – Spectra Interpretation and Selected Applications

Contact Info

Product

Resources

About