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International audienceTwo dry subtractive techniques for the fabrication of microchannels in borosilicate glass were investigated, plasma etching and laser ablation. Inductively coupled plasma reactive ion etching was carried out in a fluorine plasma (C4F8/O2) using an electroplated Ni mask. Depth up to 100 μm with a profile angle of 83°-88° and a smooth bottom of the etched structure (Ra below 3 nm) were achieved at an etch rate of 0.9 μm/min. An ultrashort pulse Ti:sapphire laser operating at the wavelength of 800 nm and 5 kHz repetition rate was used for micromachining. Channels of 100 μm width and 140 μm height with a profile angle of 80-85° were obtained in 3 min using an average power of 160 mW and a pulse duration of 120 fs. A novel process for glass-glass anodic bonding using a conductive interlayer of Si/Al/Si has been developed to seal microfluidic components with good optical transparency using a relatively low temperature (350°C)