Design and realisation of a quasi monolithic silicon load cell

In this paper, the first silicon load cell is presented designed for measuring a load up to 1000 kg. A prototype has been realised. An improved cryogenic RIE process with high aspect ratio was developed for the fabrication of thin springs. Low temperature silicon direct bonding was used for the final assembly. The mechanical structure was tested using poly silicon strain gauges. Encapsulated resonant strain gauges [1] will be used in the final design in order to obtain the desired accuracy of 0.03%