A method of ultrasonically bonding semiconductor elements includes the steps of: (a) aligning surfaces of a plurality of first conductive structures of a first semiconductor element to respective surfaces of a plurality of second conductive structures of a second semiconductor element; (b) ultrasonically forming tack bonds between ones of the first conductive structures and respective ones of the second conductive structures; and (c) forming completed bonds between the first conductive structures and the second conductive structures.