Admittance and Raman spectroscopy of nanodiamond thin films grown by HF CVD method

Diamond micro and nanocrystals continue to receive much attention due to unique optical and electronic properties that are dependent on a variety of material properties, such as size, shape, and composition. The electrical and optical properties of nanodiamonds and diamond-like carbon (DLC) are directly related to their structure, such as the types of different possible carbon sp2 and sp3 bonding and the different phases distribution, the size of nanocrystallites and nanoclusters, the types and distribution of bulk and surface defects All these have definite influence on the properties of diamond layers specially when the size of crystal is very small more atoms reside on the surface and as a result, more physical-chemical properties of nanodiamond are determined by the surface properties. The CVD diamond thin films with nanodiamond fraction indicate a conductivity as a function of the applied field due to the presence of numerous defects and charge localization sites, or ionisable sites, within the material, as well as nanodiamond and nondiamond structured carbon within grain boundaries.