Other

International Business Machines Corporation

Edward John Dombroski

William C Ward

Douglas W Phelps, Jr

William H Guthrie

Richard W Noth

James A Bilowith

A platform carries an integrated circuit (IC) (20) for handling and alignment through wire bonding operations, provides interconnections, and supports the shielded IC with uniform, controlled adhesive thickness. The platform base (10) has a flat portion which may have a slot (30) extending the length of a chip with wire-bond pads (140). The IC is mounted to the platform base with cast or contained adhesive, epoxy, or tape (50), which provides at least one adhesive surface. For several rows of wire-bond pads, there may be several slots. If the platform carries more than one chip, the platform base may have one or more slots (30, 40) per chip. A platform may carry other components (110, 120). Circuitry (90) may be printed on one or both sides of the platform base, with moderate resistivity to damp ringing of noise signals. Wire bonds are made through the slot (30), connecting IC pads with circuitry. The platform base may have conductive areas (90) on one or both sides to provide a shield or bus connected by wire bonds. Conductive bus elements (60 and 70) may be attached with tape (80). The platform may have terminals (100) for interconnection with higher level of circuitry and/or narrow leads (1220) extending over the IC. The platform base may be formed of metal, stamped in a continuous strip consisting of many individual platform segments, the individual segments being excised during assembly.

Tape application platform and processes therefor

A platform carries an integrated circuit (IC) (20) for handling and alignment through wire bonding or TAB operations, provides interconnections, and supports the shielded IC with uniform, controlled adhesive thickness. The platform base (10) has a flat portion which may have a slot (30) extending the length of a chip with wire-bond pads (140). The IC is mounted to the platform base with cast or contained adhesive, epoxy, or tape (50), which provides at least one adhesive surface. For several rows of wire-bond pads, there may be several slots. If the platform carries more than one chip, the platform base may have one or more slots (30, 40) per chip. A platform may carry other components (110, 120). Circuitry (90) may be printed on one or both sides of the platform base, with moderate resistivity to damp ringing of noise signals. Wire bonds are made through the slot (30), connecting IC pads with circuitry. The platform base may have conductive areas (90) on one or both sides to provide a shield or bus connected by wire bonds. Conductive bus elements (60 and 70) may be attached with tape (80). The platform may have terminals (100) for interconnection with higher level of circuitry and/or narrow leads (1220) extending over the IC. The platform base is preferably made from epoxy-glass laminate with conductive layers of a clad composite with preferred resistivity and preferred thermal expansion. Platform bases may be composite metal, stamped in a continuous strip, with platform segments excised during assembly. Another embodiment provides a lead paddle assembly in which two tape application platforms hold an IC in a rigid assembly.

An integrated-circuit manufacturing process uses a platform to carry an integrated circuit (IC) (20) for handling and alignment through wire bonding or TAB operations, to provide interconnections, and to support the shielded IC with uniform, controlled adhesive thickness. The platform base (10) has a flat portion which may have a slot (30) extending the length of a chip with wire-bond pads (140). The IC is mounted to the platform base with cast or contained adhesive, epoxy, or tape (50), which provides at least one adhesive surface. For several rows of wire-bond pads, there may be several slots. If the platform carries more than one chip, the platform base may have one or more slots (30, 40) per chip. A platform may carry other components (110, 120). Circuitry (90) may be printed on one or both sides of the platform base, with moderate resistivity to damp ringing of noise signals. Wire bonds are made through the slot (30), connecting IC pads with circuitry. The platform base may have conductive areas (90) on one or both sides to provide a shield or bus connected by wire bonds. Conductive bus elements (60 and 70) may be attached with tape (80). The platform may have terminals (100) for interconnection with higher level of circuitry and/or narrow leads (1220) extending over the IC. The platform base is preferably made from epoxy-glass laminate with conductive layers of a clad composite with preferred resistivity and preferred thermal expansion. Platform bases may be composite metal, stamped in a continuous strip, with platform segments excised during assembly. Another embodiment provides a lead paddle assembly in which two tape application platforms hold an IC in a rigid assembly.

A platform serves to carry an integrated circuit chip (20) for handling and alignment through wire bonding or TAB operations, provides interconnections, and supports the IC chip in its use environment. The platform base (10) has a flat portion which may have a slot (30) passing through it and extending approximately the length of an IC chip (which has wire-bond pads (140), some of which may be near a chip axis). The IC chip is mounted to the platform base with tape (50), which provides at least one adhesive surface. The tape may be a cast or contained adhesive or epoxy with or without a backing layer, or it may be a thermoplastic or thermo-setting plastic. TAB or wire-bond pads are aligned with respect to the platform slot. If the chip has more than one row of wire-bond pads, the platform may have more than one slot. If more than one chip is mounted to the platform, the platform's base may have one or more slots (30, 40) per chip. Circuitry (90) may be printed on one or both sides of the platform base. The circuitry is preferably made to have a relatively high sheet resistivity to damp ringing of noise signals. Wire bonds are made through the slot (30), connecting pads on the IC chip with printed circuitry. The platform base may have an electrically conductive area (90) on one or both sides to provide a shield, ground plane and/or power bus, connected by wire bonds to pads of the IC chip and to a higher level of circuitry. Conductive bus elements (60 and 70) having continuous wire-bond areas may be provided, attached with tape (80). The platform may have terminals (100) for interconnection with a higher level of circuitry and/or narrow leads (1220) extending over the IC chip. Components (110, 120) other than the integrated circuit chip may also be carried on the tape application platform.

This is a semiconductor chip package configuration particularly suited for stacking. These described arrangement is especially adapted to be used with the so-called Lead-On-Chip type package. Each package is of minimum size, and provided with a thermal heat sink arranged with respect to the remainder of the package to balance the stresses induced in the package during fabrication. This is accomplished by placing a lead frame on the active face of the semiconductor chip, bonding the lead frame conductors to respective input/output pads on the active face of the chip, and molding an encapsulant completely around five of the six sides of the chip but leaving a substantial portion of the sixth side unencapsulated. A heat sink is affixed on the exposed, i.e. unencapsulated, portion of the sixth side of the chip. The heat sink is comprised of a metal capable of thermally conducting and dissipating waste heat away from the chip and is of a mass, thickness, and area to counterbalance stresses such, as bending stresses, introduced into the chip by the application of the lead frame and encapsulant to the chip. The heat sink can also employed as a ground plane to provide an electromagnetic shield when the chips are arranged in a stack.

Stackable vertical thin package/plastic molded lead-on-chip memory cube

Multiple, single conductor, tape automated bonding (TAB) tapes are sequentially applied to a semiconductor device by the bonding of a first, etched, single layer TAB tape to an outer row of bonding pads on a semiconductor chip and to selected contacts on a lead frame followed by the laying down of at least one additional etched, single layer TAB tape which is then bonded to an inner row of bonding pads on the semiconductor chip and to different selected lead frame contacts. If desired the subsequent TAB tape may be adhered to the preceding TAB tape to increase the mechanical strength of all the tapes and improve the electrical characteristics of the tapes. The application of one or more ground planes to the assembly is also shown.

Growing community of inventors

Jericho, VT, United States of America

Edward John Dombroski