Fabrication and multifunction integration of microfluidic chips by femtosecond laser direct writing

Abstract

In the pursuit of modern microfluidic chips with multifunction integration, micronanofabrication techniques play an increasingly important role. Despite the fact that conventional fabrication approaches such as lithography, imprinting and soft lithography have been widely used for the preparation of microfluidic chips, it is still challenging to achieve complex microfluidic chips with multifunction integration. Therefore, novel micronanofabrication approaches that could be used to achieve this end are highly desired. As a powerful 3D processing tool, femtosecond laser fabrication shows great potential to endow general microfluidic chips with multifunctional units. In this review, we briefly introduce the fundamental principles of femtosecond laser micronanofabrication. With the help of laser techniques, both the preparation and functionalization of advanced microfluidic chips are summarized. Finally, the current challenges and future perspective of this dynamic field are discussed based on our own opinion.

Laser Direct Writing of Thick Hybrid Polymers for Microfluidic Chips

“…Laser direct writing (LDW) of thick photostructurable polymers is emerging as an interesting new technology for microfabrication [5] but there are still only few articles published on this topic. In [6] Cadarso et al used LDW technique for patterning an 85 µm thick layer of an in-house epoxy-resist (EpoDWL) similar to SU-8.…”

Design, Fabrication and Computational Characterization of a 3D Micro-Valve Built by Multi-Photon Polymerization

“…Direct Laser Writing (DLW) by multi-photon polymerization (MPP) is a very promising technique for the fabrication of three-dimensional (3D) structures with sub-micron resolution [1,2]. In particular, when the beam of an ultra-fast (picosecond or femtosecond) laser is tightly focused into the volume of a transparent, photosensitive material, the polymerization process can be initiated by nonlinear OPEN ACCESS multi-photon absorption inside the focal volume.…”

Optical screw-wrench for microassembly

“…In recent years, twophoton polymerization (2PP or TPP) has emerged as a powerful tool for the fabrication of three-dimensional (3D) microstructures 1 . The high resolution and high degree of design flexibility conferred by 2PP means that it can be applied to different microfluidic applications in which liquid fluids need to be transported, mixed, or controlled by means of valves or switches 2 . Furthermore, by using photosensitive resins that contain the appropriate nanomaterials, different functions can be incorporated into the 2PP-fabricated microstructure 3,4 .…”