摘要:
A method and structure for coupling a heat conductor (e.g., heat spreader, heat sink) to a semiconductor chip. In a first embodiment, a thermally conductive shape is formed on the heat conductor, a material in an uncured or partially cured state is dispensed on the chip and on peripheral portions of the chip, and the heat conductor is applied to the material to push the thermally conductive shape into the material such that the material is redistributed to contact both the thermally conductive shape and the chip. The material is then cured (e.g., by pressurization at elevated temperature). In a second embodiment, a thermally conductive shape is formed on the chip, a material (e.g., epoxy) in an uncured or partially cured state is dispensed on the thermally conductive shape and on peripheral portions of the chip, and the heat conductor is pushed into the material to make the material contact both the thermally conductive shape and the heat conductor. The material is then cured (e.g., by pressurization at elevated temperature). For both the first embodiment and the second embodiment, an average thickness of a peripheral portion of the cured material exceeds an average thickness of a central portion of the cured material.
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:
A method of forming BGA interconnections having improved fatigue life is disclosed. In particular, a combination of mask-defined and pad-defined solder joints are selectively positioned within the BGA package. The mask-defined solder joints possess a high equilibrium height, which forces the pad-defined solder joints to elongate, thereby making the pad-defined solder joints more compliant. Further, the pad-defined solder joints posses a slightly longer fatigue life because the stress concentrations found in the mask-defined solder joints are not present in the pad-defined solder joints. Therefore, the fatigue life of BGA packages is increased by implementing a majority of mask-defined solder joints to maintain a high equilibrium height, and selectively placing pad-defined solder joints in high stress areas of the BGA package.
摘要:
A ribbon cable includes electrical conductors surrounded by an insulator and vent tubes positioned adjacent and parallel to the conductors and insulator. The vent tubes allow airflow between an internal area of the enclosure and an external atmosphere and prevent access to the internal area of the enclosure.
摘要:
A method of making a wirebond electronic package which includes a semiconductor chip bonded to the upper surface of an organic laminate substrate, including to a thermal material located on the substrate and comprised of a plurality of thermally conductive concentric lines. These lines form paths of heat escape for the chip during operation thereof and may operate in combination with other elements to extend the heat paths. Concentric lines also assure sufficient bonding area on the substrate so as to prevent delamination of the chip from the substrate as may occur during high temperatures associated with subsequent processing such as solder ball re-flow.
摘要:
A method of producing opto-electronic cards and printed circuit boards which are adapted to provide for passive alignment of VCSELs to waveguides. Also provided are opto-electronic cards and printed circuit boards which incorporate structure providing for the passive alignment of VCSELs to waveguides.
摘要:
A method of making a flip chip package that maintains flatness over a wide temperature range and provides good heat dissipation is described. A laminate substrate is electrically connected to electrical contacts disposed on a chip and underfill material is applied between the soldered connections. A body, for example an uncured dielectric material, is applied to the chip, the laminate substrate, a thermally conductive member or combinations thereof, and thermally conductive member is disposed adjacent to the surface of the chip that is opposite the surface connected to the laminate substrate. The body is extruded between the chip and the thermally conductive member. The thickness of the thermally conductive member is determined by balancing the stiffness and the CTE of both the thermally conductive member and the laminate substrate, and the length and width of the thermally conductive member may vary but are at least the size of the corresponding length and width of the chip.
摘要:
A method of making a flip chip package that maintains flatness over a wide temperature range and provides good heat dissipation is described. A laminate substrate is electrically connected to electrical contacts disposed on a chip and underfill material is applied between the soldered connections. A body, for example an uncured dielectric material, is applied to the chip, the laminate substrate, a thermally conductive member or combinations thereof, and thermally conductive member is disposed adjacent to the surface of the chip that is opposite the surface connected to the laminate substrate. The body is extruded between the chip and the thermally conductive member. The thickness of the thermally conductive member is determined by balancing the stiffness and the CTE of both the thermally conductive member and the laminate substrate, and the length and width of the thermally conductive member may vary but are at least the size of the corresponding length and width of the chip.
摘要:
An electrical connector assembly which utilizes a double layered elastomeric for a pressure exertion member wherein the two, individual layers are of different hardness. The first layer is of a relatively low durometer elastomeric material while the second layer is of higher durometer elastomeric material and includes several projections, e.g., for engaging a circuitized substrate such as a flexible circuit. Both layers preferably have the same spring rate, while the projections of the second layer may possess a variety of different configurations, e.g., cylindrical or boxlike. The individual projections may each include extension portions which in turn are positioned within corresponding openings within the substantially solid first layer.
摘要:
A high speed interposer which includes a substrate having alternatingly oriented dielectric and conductive layers which form a substrate, openings which extend from one opposing surface of the substrate to a second opposing surface, conductive members positioned within the openings and also extending from surface to surface (and beyond, in some embodiments), and a plurality of shielding members positioned substantially around the conductive members to provide shielding therefore during the passage of high frequency signals through the conductive members.