Abstract: A sensor for measuring a parameter of a fluid includes a housing defining a fluid-proof chamber and an area of reduced thickness defining a membrane separating the chamber from the fluid. An actuating/detecting element is positioned within the chamber and mechanically coupled with the membrane. The actuating/detecting element includes a multilayer structure, having a metallic material member having a first metallized layer, and a piezoelectric material member having a second metallized layer connected to the first metallized layer via a sintered silver joint. A resonating element is mechanically coupled with the membrane and extends from the membrane, the resonating element being sized and dimensioned to transfer mechanical vibrations to and from the actuating/detecting element.