of an overhanging part of the second die during a wire bonding operation impact of the capillary tip 15 with the die pads on the overhanging part 117 of the die 116 may cause the overhanging part of the die to flex as shown by the arrow 19 and bounce and or to crack or break flex or bounce can result in poor wire bond interconnection to the die pads and cracking or breakage of the die as shown for example at 118 can destroy the circuitry on the die fig2 a and 2b illustrate a conventional approach to supporting an overhanging part of an upper die in a die stack in this example a first u201c lower u201d die 24 is affixed active side upward using an adhesive onto a die attach surface of a lower substrate 22 and the lower die is electrically connected to the substrate by wire bonds between pads on the die and wire bond sites on an metal layer in the upper layer of the substrate electrically insulating block or bar shaped spacers 25 are mounted using an adhesive upon the lower substrate outside the wire bond sites for interconnection of the lower die and parallel to rows of bond sites for electrical interconnection of the second u201c upper u201d die 224 an insulating adhesive 23 is provided over the lower die and over the upward facing surfaces of the spacers and then the second u201c upper u201d die 224 is then mounted upon the adhesive 23 on the lower die and the spacers the adhesive 23 has a thickness that is sufficient when cured that to provide clearance above the lower die 24 for the loop height of.