Fig. 1.

Schematic illustration of the fabrication procedure for 3D multilayered microfluidic chips integrated with polymer microcomponents by hybrid “all-in-one” femtosecond laser processing. a–d FLAE of a photosensitive glass to fabricate 3D multilayered glass microfluidic channels, which involves a femtosecond laser direct writing with the “control layer” strategy, b first heat treatment, c HF etching, and d second heat treatment to improve the surface smoothness. e, f Integration of high-precision polymer 3D microstructures in 3D embedded multilayered microchannels at different depths by TPP with optimized parameters. e SU-8 injection into the fabricated multilayered microchannels and prebaking with different times, which depend on the channel depth. f Direct femtosecond laser writing for TPP with different laser powers for different depths. g Developing to remove the unsolidified liquid resin after postbaking. All schematics in this figure are illustrated based on the two-layered microfluidic chip, where each channel is crossed with a right angle