Femtosecond laser assisted etching of quartz: microstructuring from inside

In quartz crystal substrates, microchannels were made by femtosecond laser assisted etching, i.e., irradiation of focused femtosecond laser pulses followed by wet etching. By the use of wet etching, the laser irradiated region was selectively etched out, and a microchannel was formed inside the quartz substrate. The laser irradiated region was found to be amorphous by transmission electron microscopy. Anisotropy in the etching rate inside the quartz was observed.