Abstract: A sensor has an electrical interconnect grown in a cavity between first and second layers that are bonded together. Electrically conductive grain growth material is selectively deposited on at least one of two electrically conductive film interconnect regions that face one another across the cavity. The grain growth material is then grown upon predetermined conditions to form the electrical interconnect between the two interconnect regions. A sensor element deposited in the cavity is electrically coupled between the layers by the interconnect. The grain growth material can be tantalum that is heated after the layers are bonded to grow grains that interconnect the electrically conductive films.