Abstract: A Cr layer with thickness of 150 nm was successfully deposited on the surface of diamond particles using DCmagnetron sputtering technique. The interface diffusion and reaction between Cr and diamond was promoted by annealing in the range from 300 ℃ to 600 ℃ in high vacuum. The Auger profile results showed that the width of interface layer was more than 90 nm. A Cr₂Ccarbide layer was formed after Cr/diamond annealed above 500 ℃. The formation of Cr₂Con the interface was confirmed by Auger line shapes. When the annealing temperature was below 500 ℃ and annealing time less than 4 h, Cr₂C₃ interface species was formed. Higher temperature and longer time resulted in Cr₂Cinterface species. The chemical reaction suggested that there was a strong chemical bond on the interface of Cr/diamond, which was one of the important factors for the high adhesion strength between metal and diamond. The interface diffusion and reaction was governed by the diffusion of carbon from diamond substrate. The activation energy of the interface diffusion reaction was 38.4 kJ/mol. The interface species varied with annealing temperature and time.

Key words: Diamond, Cr, Interface reaction, AES