研究目的

Investigating the interaction between CVD grown microcrystalline diamond and thermally evaporated Fe at elevated temperatures in the range of 400–800 ?C under vacuum conditions.

研究成果

The CVD diamond–Fe interaction in the range of 400–800 ?C is significantly lower in comparison with previously reported data for the range of temperatures 900–1300 ?C. Diamond etching and graphitization in the range of 400–800 ?C are undetectable during microscopic measurements and can be detected only by XRD and Raman measurements. Annealing of the diamond in contact with Fe slightly reduces the quality parameter in the range of 98.7–99.4%, confirming a slight interaction of diamond–Fe at the selected temperature range. Strong diffusion of carbon into the Fe occurs even at low-temperature annealing conditions of 400 ?C. Formation of an Fe–C transition layer due to the interdiffusion process in the diamond–Fe system can be detected in the temperature range 600–800 ?C. The thickness of this transition layer is relatively low (approx. 0.5 μm) due to the limited ability of the Fe3C to form. When annealing at 600 ?C, one can detect a diffusion of the Fe into the diamond film. The Fe diffusion coefficient was estimated from 1.25 × 10?17 m2 s?1 at 400 ?C up to 1.25 × 10?15 m2 s?1 at 800 ?C. The diffusion activation energy of the Fe was determined to be 69.1 kJ/mol.

研究不足

The study was limited to the temperature range of 400–800 ?C and did not explore higher temperatures where diamond etching and graphitization are more pronounced.