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Formation and evolution of black silicon microcolumns with array distribution after IR nanosecond-pulsed laser ablation

ABSTRACT The combination of low reflectivity and the semi-conductive properties of silicon found in black silicon make it a prime candidate for application in photovoltaic solar cells by manipulating the surface microstructure of the silicon. The black silicon can be produced by a complex laser ablation process both temporally and spatially. In this study, in order to explore the formation mechanism of the silicon microcolumn, the ablation area morphology was analyzed four times for 2min, 5min,10min and 20min and the analysis was induced by a 1064 nm nanosecond-pulsed laser in 10−1 Pa of ambient pressure. The experimental results indicated that the black silicon microcolumns were formed through irradiation accumulation, not instantly and stood neatly at the spot center. With the energy coupling, an increased amount of silicon became vapor and was re-deposited back onto the surface.