Experimental investigation on enhanced ablation of silicon with the combined pulse laser

The combined pulse laser (CPL) based on long-pulsed lasers has been proven to be an effective way of improving laser processing efficiency by combining their processing advantages. In this Letter, a CPL with a 500 mJ millisecond pulse and a 150 mJ nanosecond pulse is utilized to study the interaction process between laser and silicon. Based on high-speed images of plasma distribution and laser supported detonation wave (LSDW), as well as the height characteristics of ablation morphology, the energy coupling of plasma with variable delay time is analyzed. The irradiation of the material by millisecond pulse within the delay time enhances the strong coupling process between nanosecond pulse and the target.