Abstract: A microelectronic element such as a semiconductor chip has springs such as coil springs bonded to contacts so that the springs serve as electrical connections to a circuit panel. The unit can be tested readily and can be surface-mounted to a circuit panel by bonding the distal ends of the springs, remote from the microelectronic element, to the panel. The springs can also serve as antennas so as to provide a miniaturized phased array.

Abstract: A method of making a stacked microelectronic assembly includes providing a flexible substrate having a plurality of attachment sites, test contacts and conductive terminals, and including a wiring layer with leads extending to the attachment sites. The method includes assembling a plurality of microelectronic elements to the attachment sites and electrically interconnecting the microelectronic elements and the leads. The flexible substrate is then folded so as to stack at least some of the microelectronic elements in substantially vertical alignment with one another to provide a stacked assembly with the conductive terminals exposed at the bottom end of the stack and the test contacts exposed at the top end of the stack.