Surface microstructuring of single crystalline diamond based on the accumulated energy homogenization in the nanosecond pulsed laser ablation

In this paper, surface microstructuring of single crystalline diamond (SCD) by a nanosecond pulsed laser is performed. The nanometric surface characteristics of the ablated micro-grooves on the diamond caused by the thermal effect are firstly studied, where the deposited metamorphic layer, the irregular cross-sectional profile of the ablated groove and the non-uniform surface morphology are involved, and the dependence of the obtained surface characteristics on the ablation parameters of the infrared nanosecond pulsed laser, including the laser energy density, the pulse frequency, the scanning speed and the scanning times, is then analyzed and discussed. Finally, based on the mathematic analysis of the laser energy distribution and the accumulated energy intensity homogenization, the scanning path of the laser beam is programmed and five different types of surface microstructures are then fabricated on the diamond by controlling the scanning path with the optimized laser machining parameters to achieve the high surface quality of less cracking and better uniformity.