Fast multiphoton microfabrication of freeform polymer microstructures by spatiotemporal focusing and patterned excitation.

One of the limits of conventional scanning multiphoton microfabrication is its low throughput due to point-by-point processing. In order to surpass this limit, a multiphoton microfabrication system based on spatiotemporal focusing and patterned excitation has been developed to quickly provide three-dimensional (3D) freeform polymer microstructures. 3D freeform polymer microstructures using Rose Bengal as the photoinitiator are created by sequentially stacking two-dimensional fabricating patterns. The size of each fabrication area can be larger than 300 × 170 μm2 (full width at half maximum). Compared to conventional scanning multiphoton excitation and fixed mask pattern generation, this approach offers freeform microstructures and a greater than three-order increase in fabrication speed. Furthermore, the system is capable of optically sectioning the fabricated microstructures for providing 3D inspection.