54 results about "Flip chip interconnect" patented technology

A flip chip interconnect system comprises and elongated pillar comprising two elongated portions, one portion including copper and another portion including solder. The portion including copper is in contact with the semiconductor chip and has a length preferably of more than 55 microns to reduce the effect of .alpha. particles from the solder from affecting electronic devices on the chip. The total length of the pillar is preferably in the range of 80 to 120 microns.

The present invention is a method and apparatus for forming a bump for semiconductor interconnect applications, such as reverse wire bonding or stud bumping for flip chip interconnections. The bump is formed by (1) ball bonding at the bump site, (2) raising the capillary a predetermined height after forming the ball bond with the wire paying out of the capillary tip, (3) moving the capillary laterally a predetermined distance, preferably in a direction toward the site of other end of the wire loop, if the bump is to be used as the platform for a stitch bond of a wire loop, (4) raising the capillary further, and (5) moving the capillary diagonally downwardly and in the opposite direction of the first lateral motion. The wire is then severed by raising the capillary, closing the clamps and raising the capillary again to snap the wire pigtail off at the bump.

An interconnection structure suitable for flip-chip attachment of microelectronic device chips to packages, comprising a two, three or four layer ball-limiting composition including an adhesion/reaction barrier layer, and having a solder wettable layer reactive with components of a tin-containing lead free solder, so that the solderable layer can be totally consumed during soldering, but a barrier layer remains after being placed in contact with the lead free solder during soldering. One or more lead-free solder balls is selectively situated on the solder wetting layer, the lead-free solder balls comprising tin as a predominant component and one or more alloying components.

A flip chip interconnection structure is formed by mechanically interlocking joining surfaces of a first and second element. The first element, which may be a bump on an integrated circuit chip, includes a soft, deformable material with a low yield strength and high elongation to failure. The surface of the second element, which may for example be a substrate pad, is provided with asperities into which the first element deforms plastically under pressure to form the mechanical interlock.

A method comprises forming semiconductor flip chip interconnects where the flip chip comprises a wafer and a substrate having electrical connecting pads and electrically conductive posts operatively associated with the pads and extending away from the pads to terminate in distal ends. Solder bumping the distal ends by injection molding solder onto the distal ends produces a solder bumped substrate. Another embodiment comprises providing the substrate having the posts on the pads with a mask having a plurality of through hole reservoirs and aligning the reservoirs in the mask to be substantially concentric with the distal ends. This is followed by injecting liquid solder into the reservoirs to provide a volume of liquid solder on the distal ends, cooling the liquid solder in the reservoirs to solidify the solder, removing the mask to expose the solidified solder after the cooling and thereby provide a solder bumped substrate. This is followed by positioning the solder bumped substrate on a wafer in a manner that leaves a gap between the wafer and the substrate. The wafer has electrically conductive sites on the surface for soldering to the posts. Abutting the sites and the solder bumped posts followed by heating the solder to its liquidus temperature joins the wafer and substrate, after which, the gap is optionally filled with a material comprising an underfill.

A semiconductor flipchip package includes a central cavity area on the first major side for receiving a flipchip die therein. The package substrate is substantially made from a single material that serves as the support and stiffener and provides within the cavity floor all the connecting points for flipchip interconnection to the silicon die. The integral cavity wall serves as a stiffener member of the package and provides the required mechanical stability of the whole arrangement without the need for a separate stiffener material to be adhesively attached. The cavity walls may contain extra routing metallization to create bypass capacitors to enhance electrical performance. Optional methods to cover the silicon die enhance thermal performance of the package.

A flip chip interconnection system includes: providing a conductive lead coated with a protective coating; forming a groove through the protective coating to the conductive lead for controlling solder position on a portion of the conductive lead; and attaching a flip chip having a solderable conductive interconnect to the portion of the conductive lead.

The present invention provides alloys for forming sputtered under bump metallization seed layers and electroplated or otherwise deposited bump metallurgy. The alloys of the present invention are comprised of silver with gold or palladium, copper with gold, or gold with nickel or palladium which provide suitable sputtering and electrical characteristics and resistance to corrosion and tarnishing. The invention further provides for semiconductor devices made from metal alloys for UBM and bump metallurgy, and for a method of making such semiconductor devices.

The present invention relates generally to conductive polymer composites, electrically conductive adhesives, and methods of producing the same. The conductive polymer composites and electrically conductive adhesives may be used for electronic component interconnects, flip chip interconnections, electrical connections to circuit boards, jumper connections, or similar uses. The method of forming a conductive polymer composite includes mixing conductive metal flakes, functionalized conductive metal nanoparticles, and a polymer precursor and curing the polymer precursor to form a composite. In one embodiment, the conductive polymer composites may be composed of microparticles of silver flake and sintered silver nanoparticles between the silver flakes. The polymer composites have an electrical conductivity of less than 10⁻⁵ Ω·cm.

A flip-chip interconnect structure for a RFID tag is described which permits the use of an isotropic electrically conductive adhesive (ECA) without requirement of critical alignment of the chip terminal pads to antenna terminals on the substrate. The interconnect foot print utilizes design principles of standard discrete SMD terminal footprint, which does not require alignment accuracy of a NCA/ACA flip chip bonder. The use of an ECA also eliminates the need for curing the adhesive while under heat and pressure on the chip placement machine. Because of the wide placement tolerance the chips can be placed with a low cost highly productive SMT placement machine. After placement, the assemblies leave the placement machine and are cured in an oven, thereby further improving the productivity of the placement machine. Further productivity improvement is realized by the elimination of bumping which is no longer required. The overall cost reduction of the final assembly by the process of the invention is estimated at about 60 to 85 percent.

Attaching a semiconductor chip to a substrate by applying mechanical vibrations (150) to a polymeric compound (130) and the contacting areas (114, 124) of a first (113) and a second (121) metallic member immersed in the compound, while the two metallic members approach (140) each other until they touch. The mechanical vibration causes displacements of the first member relative to the second member, and the vibration includes displacements (150) oriented at right angles to the direction (140) of the approach. The polymeric compound (130) includes a non-conductive adhesive resin paste (NCP) and filler particles; the paste is deposited before the attaching step. The first member (113) is affixed to the chip and the second member (121) to the substrate.

Various exemplary embodiments provide materials and methods for flip-chip packaging technology. The disclosed flip-chip packaging technology can use a single B-stage wafer-applied photo-sensitive adhesive along with printed interconnects, which does not include conventional underfill materials and processes. In one embodiment, a photo-sensitive adhesive can be applied on a semiconductor die or a base substrate with conductive bumps printed in through-openings of the photo-sensitive adhesive. One or more semiconductor dies can be laterally packaged or vertically stacked on the base substrate using the printed conductive bumps as interconnects there-between.

A method for fabricating a flip-chip semiconductor package comprising processing a semiconductor device, for example a semiconductor chip and processing a device carrier, for example a substrate. The semiconductor device comprises bump structures formed on a surface thereof. The substrate comprises bond pads formed on a surface thereof. The semiconductor chip is heated to a chip process temperature. The chip process temperature melts solder portions on the bump structures. The substrate is heated to a substrate process temperature, wherein said substrate process temperature may be different to the chip process temperature. The semiconductor chip is spatially aligned in relation to the substrate to correspondingly align the bump structures in relation to the bond pads. The semiconductor chip is displaced towards the substrate to abut the bump structures with the bond pads to thereby form bonds there between. A system for performing the above method is also disclosed.

A flip chip interconnect pad layout has the die signal pads are arranged on the die surface near the perimeter of the die, and the die power and ground pads arranged on the die surface inboard from the signal pads; and has the signal pads on the corresponding package substrate arranged in a manner complementary to the die pad layout and the signal lines routed from the signal pads beneath the die edge away from the die footprint, and has the power and ground lines routed to vias beneath the die footprint. Also, a flip chip semiconductor package in which the flip chip interconnect pad layouts have the die signal pads situated in the marginal part of the die and the die power and ground pads arranged on the die surface inboard from the signal pads, and the corresponding package substrates have signal pads arranged in a manner complementary to the die pad layout and signal lines routed from the signal pads beneath the die edge away from the die footprint.

The invention discloses a flip-chip assembly and manufacture method thereof. Various aspects can be implemented for providing flip-chip interconnect structures for connecting or mounting semiconductor chips to supporting substrates, such as cards, circuit boards, carriers, lead frames, and the like. In general, one aspect can be a method of providing a flip-chip interconnect structure that includes providing a semiconductor work piece that includes one or more bond pads. The method also includes depositing a first non-reflowable layer that has a first melting temperature higher than a predetermined first reflow temperature. The method further includes depositing a reflowable stress relief layer that reflows at the predetermined first reflow temperature. The method additionally includes depositing a second non-reflowable layer that has a second melting temperature higher than the predetermined first reflow temperature such that the deposited reflowable stress relief layer is between the first and the second non-reflowable layers.

A single focal plane integrated circuit hybrid replaces multiple focal plane circuits and associated off-focal plane signal processing electronics. A dual function, dual color focal plane PSD sensor chip assembly includes a PSD array, a traditional pixelized camera array, a signal processing chip, and flip-chip interconnects and wirebond pads to support electronics on the signal processing chip. The camera array is made of a material sensitive to wavelengths longer than the PSD array material is sensitive to. The PSD array is disposed in the same substrate as the camera array. The PSD array tracks object locations and directs the camera array to window and zoom while capturing images. Inherent registration of PSD cells to the pixelized camera array makes responsivity map testing and spatial calibration unnecessary. Reduction in power dissipation is achieved by powering on the camera array only when the PSD detects a change in scene.

In some embodiments, a low stress, low-temperature metal-metal composite flip chip interconnect is presented. In this regard, a method is introduced consisting of combining a powder of substantially pure tin with a powder of tin alloy having a lower melting point than pure tin and depositing the combination of metals between an integrated circuit device and a package substrate. Other embodiments are also disclosed and claimed.