SCANNING-TUNNELING-MICROSCOPY OF DIAMOND-LIKE NANOCOMPOSITE FILMS

Scanning tunneling microscopy is used in the present investigation to study metal containing diamond-like nanocomposites, viz. (a-C:H)/(a-Si :O)/Me films. By comparing images taken before and after samples were annealed at 450-degrees-C for two hours, a formation of sp2-rich regio ns is found in Pt containing samples, in contrast to the high thermal stability shown for transition-metal containing samples. It indicates that the Pt engenders the ''loosening'' of the diamond-like matrix wit h a decrease in the energy barrier. These results are further confirme d by Fourier transformation infrared spectroscopy and Raman spectrosco py. The obtained micro- and nanoscale surface images and observed tran sformation from sp3 to sp2 bonding provides new understanding of the f undamental structure of diamond-like films.