Elastic bladder method of fabricating an integrated circuit package having bonding pads in a stepped cavity

Abstract From the Canadian patent

An integrated circuit package is fabricated by assembling a stack which is comprised of a plurality of thin flat epoxy-glass layers, adhesive layers between the epoxy-glass layers, and a staircase-shaped cavity. This cavity extends from an outer epoxy-glass layer to an internal epoxy-glass layer, goes parallel along a portion of the flat surface. of the internal epoxy-glass layer and, then penetrates through it. Conductors lie on the internal epoxy-glass layer including bonding pads on the flat surface portion. After the stack is assembled the outer, epoxy-glass layer and the cavity are covered with an elastic bladder. Subsequently, the stack is laminated by forcing a fluid into the bladder …