Rapid thermal process (RTP) has been carried out on the deposited nanocrystalline diamond (NCD) films. The RTP treatments performed at 800 and 1200 degrees C have been shown to exert prominent influence on the morphology and structure of the NCD films. The loss of material at grain boundaries has been observed at both 800 and 1200 degrees C RTP treatments. Large-scale amorphous SiOx nanowires with diameters of 30-50 nm and length up to 10 pm were synthesized after RTP treatment at 1200 degrees C for 60 s. The synthesized nanowires were characterized in detail by scanning electron microscopy, transmission electron microscopy, selected area electron diffraction and energy-dispersed X-ray spectrometry analysis. A possible growth mechanism has been proposed to explain the observed phenomenon. (c) 2005 Elsevier B.V. All rights reserved.