Single platform femtosecond laser microfabrication of multilayer glass microfluidic devices

The fabrication of glass microfluidic devices typically involves complex multi-step workflows that require intermediate chemical or mechanical processing. In this study, we present a single-platform femtosecond laser fabrication approach for multilayer glass microfluidic devices. The proposed method combines microchannel fabrication, inlet/outlet port drilling, and hermetic laser welding in a single fabrication workflow. Debris-free microchannels with dimensions of approximately 50 μm × 50 μm were produced using air-assisted material removal. For glass bonding, a spiral scanning-based welding strategy was employed, and fluidic testing confirmed leak-free operation up to 70 μL/min, corresponding to an estimated pressure drop of approximately 2.5 bar. The presented approach provides a fully laser-based route for rapid prototyping of multilayer glass microfluidic devices without requiring chemical processing or intermediate surface treatment steps.