Experimental Study on Fabricating Micro-Hole Arrays on CVD Diamond Film Using a Nanosecond Pulsed Laser

The increasing demand for micro-parts and miniaturization of devices has led to development of manufacturing micro-holes on different materials. In this study, micro-hole arrays were drilled on a CVD diamond film using a nanosecond pulsed laser. The effect of laser processing parameters, such as pulse width, scanning speed, and scanning times on the shape, size, and morphology of micro-holes was investigated. The entrance, exit, and cross-sectional dimensions and morphology of the micro-holes were examined. The results demonstrated that micro-hole arrays with an entrance diameter of 49.1–56.3 μm, exit diameter of 4.6–10.6 μm, and taper angle of less than 18.5° can be obtained using a nanosecond pulsed laser. It was found that pulse width has little effect on entrance diameter, however, with the increase of pulse width, the micro-hole exit diameter and depth increased, while the taper angle decreased. With the increase of laser scanning speed, the micro-hole entrance diameter decreased slightly, and there is little variation in micro-hole exit diameter and taper angle. The scanning times were found to have little effect on micro-hole entrance diameter. However, with the increase of scanning times, the micro-hole exit diameter increased and the taper angle decreased.