A packaged sensor assembly and method of forming that includes a first substrate having opposing first and second surfaces and a plurality of conductive elements each extending between the first and second surfaces. A second substrate comprises opposing front and back surfaces, one or more detectors formed on or in the front surface, and a plurality of contact pads formed at the front surface which are electrically coupled to the one or more detectors. A third substrate is mounted to the front surface to define a cavity between the third substrate and the front surface, wherein the third substrate includes a first opening extending from the cavity through the third substrate. The back surface is mounted to the first surface. A plurality of wires each extend between and electrically connecting one of the contact pads and one of the conductive elements.