WEB Top-Hat profile in Direct Laser Interference Patterning: Is it worth it?Friday (28.02.2020) 11:52 - 11:52 Poster Room Part of:
Uniform periodic microstructures formation over a large sample area is a challenging task in Direct Laser Interference Patterning (DLIP) process mainly due to the Gaussian laser beam intensity distribution inherent to most commercial lasers. In this work, a diffractive fundamental beam-mode shaper (FBS) element is combined with a DLIP optical setup to generate a square-shaped top-hat intensity distribution in the interference volume. The interference patterns produced by a symmetrical four-beam DLIP setup with Gaussian and top-top intensity distributions are measured, characterized and compared. The impact of both laser intensity distributions on process throughput as well as fill-factor is investigated and resulting microstructures height with height error over a structured surface is analyzed. Experiments showed that by utilizing top-hat shaped interference patterns it is possible to produce 35% deeper and 60% more homogeneous structures at the same throughput. The experimental results also show that structures with a certain structure's height and homogeneity can be produced also with a 40% higher throughput when employing the top-hat DLIP setup. Finally, the proposed DLIP system can be applied for a variety of applications that benefit from the nature of periodic microstructures produced at high throughput and uniformly.