Fig. 8

Pillar arrays fabricated with different laser intensity and laser focus relative distance Δz. Material: E-shell 300. a SEM image of pillars fabricated with different laser intensity and relative laser focus positions. b Measured pillars diameter wp with respect to the laser intensity I and the relative distance Δz. Laser intensity is respectively 0.74 kW/ μm2, 0.81 kW/ μm2, 0.90 kW/ μm2, and 0.96 kW/ μm2 with the correspondence of laser power 1.59 mW, 1.75 mW, 1.94 mW, and 2.07 mW. c Top view of the pillar array. d SEM image of the pillar array viewed with 45 ∘