Micro- and nanostructures inside sapphire by fs-laser irradiation and selective etching

Micro- and nanofabrication of cavities in the volume of sapphire was performed by femtosecond laser irradiation followed by chemical etching with aqueous solution of HF acid. Depending on the focusing conditions self-organized nanostructures or elliptical microchannels are produced. This manufacturing technique is potentially usable for photonic crystals in integrated optical elements or microfluidic devices for applications in life science, biology or chemistry.