Simultaneous additive and subtractive three-dimensional nanofabrication using integrated two-photon polymerization and multiphoton ablation

Abstract

Modern three-dimensional nanofabrication requires both additive and subtractive processes. However, both processes are largely isolated and generally regarded as incompatible with each other. In this study, we developed simultaneous additive and subtractive fabrication processes using two-photon polymerization followed by femtosecond (fs) laser multiphoton ablation. To demonstrate the new capability, submicrometer polymer fibers containing periodic holes of 500-nm diameter and microfluidic channels of 1-µm diameter were successfully fabricated. This method combining both two-photon polymerization and fs laser ablation improves the nanofabrication efficiency and enables the fabrication of complex three-dimensional micro-/nanostructures, promising for a wide range of applications in integrated optics, microfluidics and microelectromechanical systems. An international team of researchers has combined two well-known fabrication techniques to produce intricate three-dimensional nanostructures. Yong Fen Lu and co-workers say that their novel approach could be used to make nanosized devices that are difficult to produce through either technique alone. Both techniques employ a femtosecond laser. The first — two-photon polymerization—is used to ‘draw’ 3D structures in a photocurable polymer. The second—femtosecond laser multiphoton ablation—is used to cut voids, such as channels, in the polymer. Combining these two techniques enables the efficient fabrication of complex three-dimensional nanostructures, such as integrated optical circuits and lab-on-a-chip devices.