Near- And far-field Raman spectroscopic studies of nanodiamond composite films deposited by coaxial arc plasma

M. Ali Ali, Tanja Deckert-Gaudig, Mohamed Egiza, Volker Deckert, Tsuyoshi Yoshitake

Research output: Contribution to journalArticle

Abstract

Raman spectroscopic studies on nanodiamond composite (NDC) films, comprising nano-sized diamond grains and an amorphous carbon (a-C) matrix, deposited by coaxial arc plasma deposition are challenging because the scattering of the nano-sized diamond grains competes with the strong signal of the a-C matrix. To unravel the nanocomposite structure of NDC films, both far- and near-field Raman spectroscopy were employed. Based on the comparison of visible and ultraviolet far-field Raman data, component spectra based on either nanodiamond or a-C were estimated by a peak-decomposition procedure based on band fitting. Near-field optical resolution achieved via tip-enhanced Raman spectroscopy reveals sharper peaks of both the nanodiamond and the amorphous carbon than the far-field spectra. Consequently, the peak-decomposition procedure is not required, which evidently indicates the effective detection of nanodiamond grains embedded in a-C matrices and is a direct result of the high spatial resolution that limits the number of probed grains. The size of the nanocrystals could additionally be estimated from the profile and position of a diamond peak. This work demonstrates that tip-enhanced Raman spectroscopy is a powerful nondestructive method for nanodiamond composite films, which allows direct access to parameters hitherto only available via average data.

Original languageEnglish
Article number041601
JournalApplied Physics Letters
Volume116
Issue number4
DOIs
Publication statusPublished - Jan 27 2020

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)

Cite this