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The potential uses of diamond films can be found in a diverse range of industrial applications. However, deposition of diamond films onto some foreign materials is still not a simple task. Here we present the growth of adherent diamond films on copper rods with the focus on substrate pre-treatment by polyvinyl alcohol composite nanofibres. The primary role of the polymer fibres substantially act as a carbon source which enhances the diamond nucleation and accelerates a homogenous CVD growth. Diamond growth was carried out in pulsed linear antenna microwave chemical vapour deposition system, which is characterized by cold plasma due to larger distance of hot plasma region from the substrate, at various gas compositions. The large distance between plasma source and the substrate holder also allows the uniform deposition of diamond on a large number of substrates with complex geometry (3D objects) as well as for the vertically positioned substrates. Moreover, the inhomogeneity in diamond film thickness deposited on vertically positioned substrates was suppressed by using polyvinyl alcohol nanofibre textile. Combination of PVA polymer fibres use together with this unique deposition system leads to a successful overcoating of the copper rods by continuous diamond film without the film cracking or delamination. We propose that the sequence of plasma-chemical reactions enhances the transformation of certain number of carbon atoms into the sp³-bonded form which further are stabilized by atomic hydrogen coming from plasma. [ABSTRACT FROM AUTHOR]

Abstract: The nanocrystalline diamond (NCD) layers were grown by the large area (linear plasma) MWCVD on polished silicon substrates with and without intermediate mirror-like metallic coatings. The optical reflectance and Raman spectroscopy in the ultraviolet, visible and near infrared region (UV–VIS–NIR) reveals the thickness and the optical quality of NCD layers. The modified grazing angle reflectance (GAR) spectroscopy is applied in the mid infrared region 800–4000/cm to detect the molecular vibrations (functional groups) at the functionalized NCD surface. The optical absorbance of functionalized NCD surface is evaluated from p-polarized reflectance spectra measured at Brewster angle of incidence (BAR) to eliminate the interference fringes. We report a significant enhancement of sensitivity of BAR using NCD growth on metal mirrors. [Copyright &y& Elsevier]