Micro-blood flow measurement using thermal conductivity micro-needles: a new CMOS compatible manufacturing process onto porous silicon

Tissue thermal conductivity can be recorded thanks to a mini-invasive microsensor to control and/or study skin hydration, blood micro-flow within capillaries. Based on the same measurement protocol used for a previous "hybrid-made" microsensor, a micro-needle has been developed onto silicon using standard CMOS process. It was formed on a porous silicon based substrate which guarantees a reliable thermal insulation of the sensing elements. Sensor technological steps are presented as well as its calibration into phantoms.