Laser planarization efficiency and roughness of CVD diamond film

The orthogonal experiment of laser planarization of CVD polycrystalline diamond film was carried out, and the morphology was analyzed by using scanning electron microscope (SEM). The surface roughness Ra, the surface roughness Sa and the taper of kerf were measured by confocal laser scanning microscope. The influence of laser parameters on cutting quality was analyzed. The results show that the factors affecting kerf taper are pulse width, pulse frequency, feed speed and laser current in turn, and the factors affecting line roughness are feed speed, laser current, pulse frequency and pulse width in turn. After optimization by orthogonal test, the best groove surface morphology can be obtained with laser current of 64 A, pulse width of 400 μs, pulse frequency of 275 Hz and feed speed of 100 mm/min. Using the optimized parameters, the surface roughness Sa was measured to be 11.7 μm. When the incident angle increased to 75°, the surface roughness Sa decreased to 1.9 μm, and the actual removal efficiency reached 1.1 mm3/min.