Loading patent…
AssigneeInternational Business Machines Corporation
InventorsKishor V. Desai, Kohn Harold
Estimating the term…
A method and apparatus are disclosed for mounting a flexible film semiconductor chip carrier on a second level electronic package, such that the flexible film of the carrier is supported substantially in a plane above the surface of the second level electronic package. The method comprises positioning preformed spacers embedded in a dissolvable polysulfone foam holder between the outer lead bonding pads on the flexible film semiconductor chip carrier and corresponding (matching) bonding pads on the second level electronic package. Each of the preformed spacers may comprise, for example, a solder cylinder with a copper core. The preformed spacers may be bonded to the outer lead bonding pads on the chip carrier, and to the matching bonding pads on the second level electronic package, by reflowing the solder of the spacers using, for example, a conventional solder reflow oven. Then, the holder is dissolved, and washed away, in a conventional vapor degreaser using, for example, methylene chloride, to leave the flexible film semiconductor chip carrier mounted on the second level electronic package with the flexible film of the carrier having a planar geometry as desired.
A method for outer lead bonding a circuitized, flexible sheet of polyimide film having a thickness of less than approximately 127.0 micrometers (about 0.005 inch) which is mounted on a frame and which is carrying an electronic device, onto a circuitized substrate having mounting pads thereon in a pattern matching a corresponding pattern of outer lead bonding pads on the circuitized, flexible film, which comprises the steps of:
Dependencies are inferred from the claim text.