New bulk accelerometer for triaxial detection

A new structure for a piezoresistive triaxial accelerometer has been designed and fabricated. The FEM simulations shows a null cross sensitivity for the x and y detection and a very low level one for the z direction, <1.6%. The metal lines and the thickness of the passivation silicon oxide layers have been reduced to decrease stresses in the devices. The technology for the devices is a combination of bulk and surface micromachining based on commercial BESOI wafers.