Femtosecond Laser 3D Fabrication in Porous Glass for Micro- and Nanofluidic Applications

Abstract

Abstract:The creation of complex three-dimensional (3D) fluidic systems composed of hollow micro-and nanostructures embedded in transparent substrates has attracted significant attention from both scientific and applied research communities. However, it is by now still a formidable challenge to build 3D micro-and nanofluidic structures with arbitrary configurations using conventional planar lithographic fabrication methods. As a direct and maskless fabrication technique, femtosecond laser micromachining provides a straightforward approach for high-precision, spatially-selective, modification inside transparent materials through nonlinear optical absorption. In this paper, we demonstrate rapid fabrication of high-aspect-ratio micro-and/or nanofluidic structures with various 3D configurations by femtosecond laser direct writing in porous glass substrates. Based on this approach, we demonstrate several functional micro-and nanofluidic devices including a 3D passive microfluidic mixer, a capillary electrophoresis (CE) analysis chip, and an integrated micro-nanofluidic system for single DNA analysis. The possible mechanisms behind the formation of high-aspect-ratio micro-and nanochannels are also discussed. This technology offers new opportunities to develop novel 3D micro-nanofluidic systems for a variety of lab-on-a-chip applications.

From random inhomogeneities to periodic nanostructures induced in bulk silica by ultrashort laser

“…Thus, a control over the nanostructure properties is probably possible by slightly doping fused silica. The performed study helps to better understand the phenomena involved in volume nanograting development, which is crucial for the development of a wide range of applications in femtosecond laser material processing, particularly, nanofluidic channels for biomedicine and DNA molecular analysis, optical data storage devices, and computer-generated holograms for informatics [20][21][22][23][24][25][26].…”

“…A rigorous study of the phenomenon was performed by Taylor et al, where three regimes of femtosecond laser dielectric modification at different laser conditions were underlined [4]: (i) smooth modification, (ii) birefringent modification enabling nanograting self-organization, and (iii) disruptive modification at higher pulse energy and longer pulse duration. An ability to influence the resulting properties of femtosecond laser-written nanoplanes by changing laser parameters has opened up new opportunities in direct writing [3], developing polarization-sensitive devices [20][21][22], fabrication of nanofluidic channels [23][24][25], and five-dimensional optical data storage [26]. Several experimental works then investigated the evolution of nanograting formation [7,19,27,28].…”

Optical Sensitivity of Waveguides Inscribed in Nanoporous Silicate Framework

“…The pulse energy and scanning speed are two critical parameters determining future waveguide morphology and geometry during the LDW step. The waveguides observed by optical microscopy possess the shape of an elongated ellipse in the cross-section, which is the direct evidence of a filament structure appearance [ 38 ]. These filaments are characterized by height in the range of 50–400 µm ( Figure 2 a) and width 4–7 µm.…”

Recent Advancements in the Fabrication of Functional Nanoporous Materials and Their Biomedical Applications

“…Laser techniques have widely been employed to generate micro- and nanopatterned surfaces [ 130 ], microfluidic channels [ 131 ], and tiny photonic waveguide structures [ 131 ]. Laser irradiation in combined with dealloying strategies have been explored for fabricating nanoporous materials.…”