摘要:
A process of copper plating a through-hole in a printed circuit board, and the printed circuit board made from such process. The process comprises: providing a printed circuit board with at least two copper interconnect lines separated by an insulator in the vertical direction; providing a through-hole in the printed circuit board in the vertical direction such that the interconnect lines provide a copper land in the through-hole; applying a seed layer to an interior surface of the through-hole; removing an outermost portion of the seed layer from the interior surface of the through-hole with a laser; applying copper on the seed layer.
摘要:
A portion of compliant material includes four walls defining a slot. The slot has a relatively large cross-section end in fluid communication with a solder reservoir, and also has a relatively small cross-section end opposed to the relatively large cross-section end. The slot has a generally elongate rectangular shape when viewed in plan, with a length perpendicular to a scan direction, a width, parallel to the scan direction, associated with the relatively large cross section end, and a width, parallel to the scan direction, associated with the relatively small cross section end. The slot is configured in the portion of compliant material such that the relatively small cross-section end of the slot normally remains substantially closed, but locally opens sufficiently to dispense solder from the reservoir when under fluid pressure and locally unsupported by a workpiece. Methods of operation and fabrication are also disclosed.
摘要:
A portion of compliant material includes four walls defining a slot. The slot has a relatively large cross-section end in fluid communication with a solder reservoir, and also has a relatively small cross-section end opposed to the relatively large cross-section end. The slot has a generally elongate rectangular shape when viewed in plan, with a length perpendicular to a scan direction, a width, parallel to the scan direction, associated with the relatively large cross section end, and a width, parallel to the scan direction, associated with the relatively small cross section end. The slot is configured in the portion of compliant material such that the relatively small cross-section end of the slot normally remains substantially closed, but locally opens sufficiently to dispense solder from the reservoir when under fluid pressure and locally unsupported by a workpiece. Methods of operation and fabrication are also disclosed.
摘要:
An electronic device assembly is provided which includes a substrate, an interposer and an integrated circuit chip. The substrate is fabricated of a first material having a first thermal expansivity, and the interposer and integrated circuit chip are fabricated of a second material having a second thermal expansivity. The second thermal expansivity is different from the first thermal expansivity so that there is a coefficient of thermal expansion mismatch between the substrate and the interposer or chip. The interposer is coupled to the substrate via a first plurality of electrical contacts and an underfill adhesive at least partially surrounding the electrical contacts to bond the interposer to the substrate and thereby reduce strain on the first plurality of electrical contacts. The integrated circuit chip is coupled to the interposer via a second plurality of electrical contacts only, without use of an adhesive surrounding the second plurality of electrical contacts.
摘要:
A process for aligning at least two layers in an abutting relationship with each other comprises forming a plurality of sprocket openings in each of the layers for receiving a sprocket of diminishing diameters as the sprocket extends outwardly from a base, with the center axes of the sprocket openings in each layer being substantially alignable with one another, the diameter of the sprocket openings in an abutting layer for first receiving the sprocket being greater than the diameter of the sprocket openings in an abutted layer. This is followed by forming a plurality of reservoir openings in each of at least two of the layers and positioning the sprocket openings in the layers to correspond with one another and the reservoir openings in the layers to correspond with one another so that substantial alignment of the center axes of the corresponding sprocket openings in the layers effects substantial alignment of the center axes of the corresponding reservoir openings in the layers. Engaging the sprocket openings with the sprocket by inserting the end of the sprocket having the smallest diameter into the sprocket openings having the largest diameter in the layers and continuing through to the sprocket opening having the smallest diameter in the layers effects substantial alignment of the center axes of the corresponding sprocket openings and substantial alignment of the center axes of the corresponding reservoir openings in the layers. The invention also comprises apparatus for performing this process.
摘要:
An interconnection structure suitable for flip-chip attachment of microelectronic device chips to packages, comprising a two, three or four layer ball-limiting metallurgy 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.
摘要:
The present disclosure relates generally to semiconductor, integrated circuits, and particularly, but not by way of limitation, to centrifugal methods of filling high-aspect ratio vias and trenches with powders, pastes, suspensions of materials to act as any of a conducting, structural support, or protective member of an electronic component.
摘要:
A process of copper plating a through-hole in a printed circuit board, and the printed circuit board made from such process. The process comprises: providing a printed circuit board with at least two copper interconnect lines separated by an insulator in the vertical direction; providing a through-hole in the printed circuit board in the vertical direction such that the interconnect lines provide a copper land in the through-hole; applying a seed layer to an interior surface of the through-hole; removing an outermost portion of the seed layer from the interior surface of the through-hole with a laser; applying copper on the seed layer.
摘要:
A process of copper plating a through-hole in a printed circuit board, and the printed circuit board made from such process. The process comprises: providing a printed circuit board with at least two copper interconnect lines separated by an insulator in the vertical direction; providing a through-hole in the printed circuit board in the vertical direction such that the interconnect lines provide a copper land in the through-hole; applying a seed layer to an interior surface of the through-hole; removing an outermost portion of the seed layer from the interior surface of the through-hole with a laser; applying copper on the seed layer.
摘要:
A cleavable epoxy resin composition suitable for encapsulating electronic chips comprising the cured reaction product of a diepoxide containing a cyclic anhydride curing agent and an amine promoter.