Laser Micro-Raman Spectroscopy of CVD Nanocrystalline Diamond Thin Film

Abstract

Laser micro-Raman spectroscopy is an ideal tool for assessment and characterization of various types of carbonbased materials. Due to its special optical properties (CrN) coated stainless steel substrates. NCD films have been investigated by laser micro-Raman spectroscopy. The fingerprint of diamond based materials is in the spectral region of 1000-1600 cm -1 in the first order of Raman scattering spectrum. By using of Gaussian peak fitting, characteristic peaks in the micro-Raman spectrum of NCD films including diamond peak (D), NCD features, a vibrational density of states (VDOS) in the ultra-nanocrystalline diamond (UNCD) clusters, graphitic (G) band and disordered (D) band can be assigned. These peaks and bands can be broadened, shifted in the spectral region or may be eliminated from the spectra due to NCD films grain sizes, synthesis conditions and other surface effects on the crystals. The increasing grain sizes to about 100 nm and faceted grains as the most important parameters can promote the diamond Raman signal, eliminate the VDOS, UNCD and even NCD features in the Raman spectrum.

Observation of Graphite-Like and Diamond-Like Nanostructures in the Raman Spectra of Natural and Synthesized MoS2 Crystals with Small Carbon Additives

“…In what follows, we will denote this spectral component as D(k') (k' ≈ k/2). Our results are confirmed by the observation of similar vibrational D and D(k) bands with frequencies at 1148 and 1239 cm -1 in the Raman spectra of thin CVD nanocrystalline diamond films with a grain size of 10 -35 nm [47]. A similar G(k') component close to 1457 cm -1 in Fig.…”

Effect of nanodiamonds surface deposition on hydrophilicity, bulk degradation and in-vitro cell adhesion of 3D-printed polycaprolactone scaffolds for bone tissue engineering

“…Another two peaks around 1100 cm −1 and 1441 cm −1 represented a fingerprint of the nanoscale size of the deposited NDs [87]. Interestingly, the high purity and quality of the deposited NDs were confirmed by the absence of the D-band that might appear at around 1350 cm −1 in the Raman spectrum [24,59,84]. This could be attributed to the post-treatment of the deposited NDs by oxygen plasma that increased the diamond phase purity and quality as reported by Yang and Teii [88].…”

“…This peak was assigned to the sp 3 -bonded carbon phase and represented the optical phonon large diamond crystals (aggregated NDs). This diamond peak was relatively broad and of lower intensity owing to the small crystal size of the aggregated NDs [59,84].…”

“…The second characteristic feature of the treated group was the G-band at 1530 cm −1 , which was assigned to the bond stretching of all carbon-carbon double-bonded pairs of sp 2 atoms that were often observed together with the NDs' surfaces and grain boundaries [59,85,86]. The diamond peak and Gband are considered the most important characteristic features in the Raman spectrum of NDs.…”

“…The G-band indicated the presence of disordered carbon or graphite carbon, which was often observed together with NDs. Another two peaks around 1100 cm −1 and 1441 cm −1 were observed and assigned to the TPA (trans-polyacetylene) fragments at the boundary of diamond grains [58,59].…”