Three-dimensional microfluidic channel with arbitrary length and configuration fabricated inside glass by femtosecond laser direct writing

We demonstrate, for the first time to the best of our knowledge, fabrication of three-dimensional microfluidic channels with arbitrary lengths and configurations inside glass by femtosecond laser direct writing. The main fabrication process includes two steps: (1) direct formation of hollow microchannels in a porous glass substrate immersed in water by femtosecond laser ablation and (2) postannealing of the glass substrate at similar to 1150 degrees C by which the porous glass can be consolidated. We show that a square-wavelike channel with a total length of similar to 1.4 cm and a diameter of similar to 64 mu m can be easily produced similar to 250 mu m beneath the glass surface. (C) 2010 Optical Society of America