Patent ID: 7125789

Claim:
A method for forming connection members and assembling said members on the contact pads on a semiconductor device comprising the steps of: providing a metal sheet with a top surface and a bottom, having a core layer of a non-reflowable metal and a layer of reflowable material adherent to each surface, the thickness of said sheet determining the height of said connection members; providing a two-part die for guiding a stamping punch, each part having a structure to match the pattern of said contact pads; positioning and clamping said sheet between said die parts; providing a stamping punch having a plurality of stamping pins, the diameter of said pins determining the diameter of said connection members, said pins distributed to match said contact pad distribution; aligning said punch, said die having said sheet clamped between said parts and said semiconductor device so that each stamp pin is located over one of said contact pads; pressing said punch through said die and said sheet so that each stamping pin punches a connection member from said sheet, creating one connection member for each contact pad; bringing said members in surface contact with said pads; applying heat to said individual members and said device to melt said reflowable material between said members and said pads; and cooling the temperature below the reflow temperature whereby each member becomes firmly attached to its respective pad.