LAUSR

Abstract A dual RF inductively coupled plasma jet without the sheath gas was designed to grow diamond. The used radio frequencies were 13.56 MHz and 4 MHz, respectively. In this tandem RF system, the high electron temperature (~ 2.48 eV) and the high electron density (~ 6.65 × 10 21  m − 3 ) were found by analyzing the gas phase diagnosis results of optical emission spectra (OES). Nanocrystalline diamond films were deposited with the typical cauliflower-like morphology and the individual nodules morphology observed by the field emission electron microscopy (SEM). The surface roughness and crystalline phase of samples were measured by Atomic force microscopy (AFM) and X-ray diffraction (XRD). The Williamson-Hall (W-H) analysis was used to study the individual contribution of crystallite sizes and lattice strain on the peak broad of diamond, inferring that probably presence of stress and defects in nanodiamond. Raman spectra with an intense broad band near 1140 cm − 1 , confirmed the presence of the nanocrystalline diamond phase with few of sp 2 carbon.