Autonomous multi-sensor micro-system for measurement of ocean water salinity

This paper describes the design, fabrication and application of a micro-fabricated salinity sensor system. The theoretical electrochemical behaviour is described using electrical equivalent diagrams and simple scaling properties are investigated analytically and numerically using finite element method (FEM). The chip design and fabrication is described and measurement results of two different electrode designs are presented. The 4 mm x 4 mm multi-sensor allows for salinity determination with an accuracy of +/- 0.5 psu through determination of the electrical conductivity, temperature and pressure with accuracies of +/- 0.6 mS, +/- 0.065 degrees C and +/- 0.05 bar, respectively.