The influence of nitrogen addition on the morphology, growth rate, and Raman spectra of combustion grown diamond

摘要

The influence of intentional nitrogen addition on diamond deposition using a low pressureacetylene-oxygen flat flame was studied. The film morphology was assessed by scanning electronmicroscopy, growth rates by cross-section thickness measurements, and nitrogen incorporation byRaman spectroscopy. It was found that the addition of nitrogen increased the growth parameter z,and for the conditions investigated <100> textured films were obtained for nitrogen levels betweenthree and five parts per thousand (ppt). It was found that there was no change in growth rate over therange 0-7 ppt N{sub}2 addition. At higher levels the films became amorphous. For low levels (<5 ppt)the luminescence signal in the Raman spectra increased steadily with nitrogen addition, while thefeatures associated with sp{sup}2 and sp{sup}3 bonded carbon were unchanged. Comparisons withnatural diamond and hot-filament grown material demonstrate that nitrogen is a significant impurity inour acetylene source. Equilibrium calculations showed that NO and atomic nitrogen were the twodominant products that may be responsible for the observed changes in morphology and Ramanspectra.