Design and evaluation process of a robust pressure sensor for measurements in boundary layers of liquid fluids

In this work, the latest results of the design, fabrication and characterization of a new MEMS piezoresistive pressure sensor are presented. Significant changes in the layout as well as in the micro-fabrication process have been made, e.g. anodic bonding of a glass cover on the backside. The sensor has been developed in order to meet the special requirements of measurements in fluid mechanics, particularly with regard to the non-intrusive nature of the sensor. The sensor development, starting with the simulation of mechanical stresses within the diaphragm resulting from a pressure of up to 4 bar is described. These calculations have lead to an optimized placement of the piezoresistors in order to achieve a maximum sensitivity. Important parameters including sensitivity, resonance frequency and maximum load are described precisely. The experiments and the initial results, e.g. its linearity and its dynamic capability are demonstrated.