摘要:
A method of making an electronic package is described, wherein a substrate is provided with a pattern of conductive pads and a portion of solder positioned on selected ones of the pattern of copper pads. The solder is then reflowed to form partial hemispherically shaped caps on the selected copper pads. The partial hemispherically shaped caps are then coated with a solder flux. A thin semiconductor chip with a pattern of conductive elements, corresponding to partial hemispherically shaped capped pads, is then positioned on the substrate so that the conductive elements of the thin semiconductor chip substantially line up with the partial hemispherically shaped capped pads of the substrate. The solder is then heated to reflow temperature and an electrical couple is formed between the thin semiconductor chip and the substrate. Since all the solder necessary to make the electrical couple is positioned on the substrate, it is possible to use a thin semiconductor chip in the electronic package avoiding the problem presented by the handling and processing steps associated with securing a bumped wafer substrate during the thinning process and in subsequent processes of making the thinned semiconductor chip from the bumped wafer, for example, the dicing step.
摘要:
A microelectronic unit can include a lead frame and a device chip. The lead frame can have a plurality of monolithic lead fingers extending in a plane of the lead frame. Each lead finger can have a fan-out portion and a chip connection portion extending in the lead frame plane. The fan-out portions can have first and second opposed surfaces and a first thickness in a first direction between the opposed surfaces. The chip connection portions can have a second thickness smaller than the first thickness. The chip connection portions can define a recess below the first surface. The device chip can have a plurality of at least one of passive devices or active devices. The device chip can have contacts thereon facing the chip connection portions and electrically coupled thereto. At least a portion of a thickness of the device chip can extend within the recess.
摘要:
A component can include a substrate having a first surface and a second surface remote therefrom, an opening extending in a direction between the first and second surfaces, and a conductive via extending within the opening. The substrate can have a CTE less than 10 ppm/° C. The conductive via can include a plurality of base particles each including a first region of a first metal substantially covered by a layer of a second metal different from the first metal. The base particles can be metallurgically joined together and the second metal layers of the particles can be at least partially diffused into the first regions. The conductive via can include voids interspersed between the joined base particles. The voids can occupy 10% or more of a volume of the conductive via.
摘要:
An apparatus and method, the apparatus includes a substrate configured to support a plurality of dielectric layers, a device coupling area positioned in the substrate, and a plurality of gas exit apertures formed through the substrate. The plurality of gas exit apertures is configured to provide venting of at least one of moisture and outgassed material and the device coupling area is configured to receive an electronic device coupleable to the plurality of dielectric layers.
摘要:
A method and an arrangement for measuring the cooling rate and thermal gradient between the top and bottom surfaces of a printed circuit board. Moreover, it is intended to facilitate control over the temperature gradient which is encountered between the top and bottom of the PCB so as to prevent warpage thereof during the formation of solder joints in a reflow solder oven.
摘要:
Method and apparatus are disclosed for mounting a flexible film semiconductor chip carrier on a second level electronic package. The resulting electronic packaging structure includes electrically conductive spacers, such as solder balls or solder coated copper balls, which electrically interconnect outer lead bonding pads on the flexible film semiconductor chip carrier and corresponding bonding pads on the second level electronic package, and which physically support the flexible film of the semiconductor chip carrier substantially in a plane above the surface of the second level electronic package. This electronic packaging structure is made using a special assembly fixture comprising a base plate, a pressure insert with a resilient member, and a top plate. The flexible film semiconductor chip carrier with the spacers attached thereto is placed over the resilient member of the pressure insert which is clamped together with the second level electronic package between the top and base plates. Then, this assembly is heated to reflow the solder of the spacers, and the assembly fixture is disassembled,; leaving 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.
摘要:
Method and apparatus are disclosed for mounting a flexible film semiconductor chip carrier on a second level electronic package. The resulting electronic packaging structure includes electrically conductive spacers, such as solder balls or solder coated copper balls, which electrically interconnect outer lead bonding pads on the flexible film semiconductor chip carrier and corresponding bonding pads on the second level electronic package, and which physically support the flexible film of the semiconductor chip carrier substantially in a plane above the surface of the second level electronic package. This electronic packaging structure is made using a special assembly fixture comprising a base plate, a pressure insert with a resilient member, and a top plate. The flexible film semiconductor chip carrier with the spacers attached thereto is placed over the resilient member of the pressure insert which is clamped together with the second level electronic package between the top and base plates. Then, this assembly is heated to reflow the solder of the spacers, and the assembly fixture is disassembled, leaving 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. The spacers may be attached to the flexible film semiconductor chip carrier using a special template having a pattern of openings corresponding to the pattern of outer lead bonding pads on the flexible film semiconductor chip carrier.
摘要:
A controlled collapse chip connect method of joining an IC chip to a microelectronic circuit card. According to the method an inhomogeneous, anisotropic column of solder is deposited from a Pb/Sn alloy onto solder wettable I/O terminals of the I/C chip, without subsequent homogenizing reflow. The solder core has a Pb rich core and an Sn rich cap. The matching footprint of the solder wettable I/O terminals on the microelectronic circuit card is substantially free of deposited solder and presents a protected Cu surface to the solder columns, or, at most a surface of Cu and anti-oxidant. The chip is aligned with the corresponding footprints on the microelectronic circuit card, and the solder is reflowed to bond the chip to the microelectronic circuit card.
摘要:
A component can include a substrate having a first surface and a second surface remote therefrom, an opening extending in a direction between the first and second surfaces, and a conductive via extending within the opening. The substrate can have a CTE less than 10 ppm/° C. The conductive via can include a plurality of base particles each including a first region of a first metal substantially covered by a layer of a second metal different from the first metal. The base particles can be metallurgically joined together and the second metal layers of the particles can be at least partially diffused into the first regions. The conductive via can include voids interspersed between the joined base particles. The voids can occupy 10% or more of a volume of the conductive via.
摘要:
A microelectronic unit can include a lead frame and a device chip. The lead frame can have a plurality of monolithic lead fingers extending in a plane of the lead frame. Each lead finger can have a fan-out portion and a chip connection portion extending in the lead frame plane. The fan-out portions can have first and second opposed surfaces and a first thickness in a first direction between the opposed surfaces. The chip connection portions can have a second thickness smaller than the first thickness. The chip connection portions can define a recess below the first surface. The device chip can have a plurality of at least one of passive devices or active devices. The device chip can have contacts thereon facing the chip connection portions and electrically coupled thereto. At least a portion of a thickness of the device chip can extend within the recess.