The magnetic field is an important non-contacting energy field that can affect material synthesis. In this study, a dynamic magnetic field with an angular frequency of 100 π rad/s was applied in hot filament chemical vapor deposition, and its effects on diamond nucleation were intensively investigated by scanning electron microscopy, transmission electron microscopy, atomic force microscope, grazing incidence X-ray diffraction, and Raman spectroscopy. The results showed that the dynamic magnetic field enhanced diamond nucleation, with deposited diamonds having a large crystal grain size and high crystallinity. Furthermore, the angular frequency of the dynamic magnetic field was varied from 83 to 600 π rad/s, and the diamond nucleation density was measured to clarify the corresponding enhancement of the dynamic magnetic field. The diamond nucleation density zigzagged from 1.48 × 109 to 2.49 × 109 cm−2 over the investigated angular frequency range but was well-fitted to the electric field excited by a dynamic magnetic field. The enhancement of the dynamic magnetic field in diamond nucleation was ascribed to electron-stimulated hydrogen desorption.
Read full abstract