Control of semiconductor surface morphology and wettability via nanosecond laser texturing

Efficient thermal management in modern compact electronics requires surfaces with controlled wettability and strong wicking capability. Although laser-textured silicon is widely studied for its optical response, its wetting and capillary transport properties remain less explored. In this work, silicon wafers were processed using a nanosecond Nd:YAG laser to create two types of textured surfaces, GraySi and BlackSi. The resulting microstructures were characterized in terms of morphology, wettability, and wicking performance using the Wi number. BlackSi exhibited significantly greater wicking capability (Wi = 2.3) compared to GraySi (Wi = 1.3). The evaporation behavior of water droplets was also investigated. Laser texturing was shown to reduce evaporation time due to enhanced hydrophilicity and, importantly, to modify the evaporation mode: BlackSi maintained a constant contact radius regime, while GraySi transitioned to a mixed regime.