Surface structure and electric properties of nitrogen incorporated NCD films.

Linear characteristics were shown in I-V curves for nanocrytalline diamond (NCD) films deposited in a nitrogen rich atmosphere by microwave plasma chemical vapor deposition (MPCVD). In order to figure out how grain size, fraction and structure of N incorporated NCD films influence the electric performances of NCD films, the scanning electron microscopy (SEM), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy were applied. Different surface morphologies are shown while the nitrogen concentration was varied. A similar tendency of electrical conductivity change versus grain size decrease and grain boundary network increase in NCD films has been observed. C1s core-energy, N1s core-energy and Raman spectra showed that the fraction and the chemical bonds of carbon atoms varied when the N 2 concentration in plasma was different. All these measurements indicate that N 2 concentration in plasma is a critical parameter for the growth, grain size, chemical bond and the electrical performance of deposited NCD films. [ABSTRACT FROM AUTHOR]