Abstract:
A method and apparatus for vertically interconnecting stacks of silicon segments. Each segment includes a plurality of adjacent die on a semiconductor wafer. The plurality of die on a segment are interconnected on the segment using one or more layers of metal interconnects which extend to all four sides of the segment to provide edge bonding pads for external electrical connection points. After the die are interconnected, each segment is cut from the backside of the wafer using a bevel cut to provide four inwardly sloping edge walls on each of the segments. After the segments are cut from the wafer, the segments are placed on top of one another to form a stack. Vertically adjacent segments in the stack are electrically interconnected by applying electrically conductive epoxy to all four sides of the stack. The inwardly sloping edge walls of each of the segments in the stack provide a recess which allows the electrically conductive epoxy to access the edge bonding pads and lateral circuits on each of the segments once the segments are stacked. The stack of electrically interconnected segments is then mounted below the surface of a circuit board and electrically connected to circuits on the board by applying traces of electrically conductive epoxy between the bonding pads on the top segment of the stack and the circuit board.
Abstract:
The present invention provides a copper-clad laminate characterized in that an electrolytic copper foil on the glossy (shiny) surface side of which a copper electrodeposit is formed, is bonded at its glossy surface side to one side or each of both sides of a substrate, which has a fine-pitch wiring (circuit) pattern and exhibits a high etching factor. The present invention further provides a copper-clad laminate which can be suitably employed in the production of such a printed wiring board.
Abstract:
A hybrid integrated circuit device includes a circuit board having at least two electrical conductors; a chip resistor bridgingly disposed across two of the electrical conductors of the circuit board; and solder electrically connecting the chip resistor to the two electrical conductors. The chip resistor has an electrically insulating substrate, two electrodes disposed on the electrically insulating substrate, separated from each other, and each electrode has a contact end electrically contacting the electrical conductors of the circuit board and a resistor element disposed on the electrically insulating substrate and electrically connected to the contact ends of the electrodes. The solder electrically connects the electrodes of the chip resistor to the electrical conductors of the circuit board.
Abstract:
The present invention provides a copper-clad laminate characterized in that an electrolytic copper foil on the glossy surface side of which a copper electrodeposit is formed, is bonded at its glossy surface side to one side or each of both sides of a substrate, which has a fine-pitch wiring (circuit) pattern and exhibits a high etching factor. The present invention further provides a copper-clad laminate which can be suitably employed in the production of such a printed wiring board.
Abstract:
A family of modular hybrid assemblies with high frequency interconnections is effected by a high frequency circuit assembly attached to a motherboard. Each assembly comprises standardized conducting elements and customizable transitions and circuit regions. The customizable transitions can be placed anywhere along the conducting element and are capable of low and high frequency performance. Attachment of the assembly can be effected via a standardized clamping structure which compresses an elastomeric member upon the conducting elements or by bending the conducting elements and soldering on end to attachment sites on the motherboard. Each member of the family of modular hybrid assemblies provides a controlled impedance transition from a transmission line on the circuit assembly to a transmission line on the motherboard.
Abstract:
A method of bonding a flexible circuitized substrate to a circuitized substrate (e.g., printed circuit board) to interconnect selected circuitry of both substrates using solder. Solder paste is applied over conductive pads on the circuitized substrate and organic dewetting material (e.g., epoxy coating) adjacent thereto. The flexible substrate, having conductors located within and/or traversing an aperture in the flexible substrate's dielectric, is positioned above the solder paste and heat is applied (e.g., in an oven). The paste, dewetting from the organic material, "balls up" and substantially surrounds a solder member (ball) attached to a bridging portion of the flexible substrate's conductor, thereby connecting both substrates. A frame member may be used to align the flexible substrate, both during solder member attachment thereto, as well as for aligning the flexible substrate having solder members attached, to the respective solder paste locations on the lower substrate.
Abstract:
An active connector assembly (10) for use in acting on electrical signals is disclosed. The assembly (10) includes a receptacle (14) for mounting on a printed circuit board (30), a pin header (12) for receiving signals from other data handling systems and a circuit card (16) attached electrically and mechanically along one edge (16a) to contact elements (26) in the pin header (12) and having an opposing edge (16b) for insertion into the receptacle (14) and electrical engagement with contact elements (28) therein.
Abstract:
To provide heat dissipation from components mounted on a printed circuit board, a copper layer is applied to a printed circuit board. A layer of pure aluminum is applied to this copper layer by electroplating. The printed circuit board is coated on both sides with copper and pure aluminum layers. The components are mounted on one of the copper and pure aluminum layers. The printed circuit board has bores in the regions of the components. The copper and pure aluminum layers extend over the inner walls of these bores, whereby communication is established between the copper and pure aluminum layer in contact with the components and the copper and aluminum layer on the opposite side of the printed circuit board. The pure aluminum layer applied by electroplating is mechanically machined in the region of the components to achieve a planar surface. Areas are left open in the copper and pure aluminum layer. Soldering contacts and strip conductors are arranged provided on the printed circuit board within these left-open areas.
Abstract:
A structure of joining two printed circuit boards with solder. A reserve solder layer is applied on a pattern of joint leads of the printed circuit on a base plate of the first board. A similar pattern of high thermal conductivity to the pattern of joint leads of the second printed circuit board is formed on the opposite or back surface of the base plate thereof in almost or exact coincidence with the latter. To join the first and second boards, the latter is turned upside down and then its joint lead pattern is put on the solder layer in registry with that of the first board. And it is at a point on each patch of the thermal conductivity pattern that heat is then applied thereto to obtain the structure between the joint leads of the two printed circuit boards.
Abstract:
A method and apparatus are disclosed for mounting a flexible film semiconductor chip carrier on a second level electronic package, such that the flexible film of the carrier is supported substantially in a plane above the surface of the second level electronic package. The method comprises positioning preformed spacers embedded in a dissolvable polysulfone foam holder between the outer lead bonding pads on the flexible film semiconductor chip carrier and corresponding (matching) bonding pads on the second level electronic package. Each of the preformed spacers may comprise, for example, a solder cylinder with a copper core. The preformed spacers may be bonded to the outer lead bonding pads on the chip carrier, and to the matching bonding pads on the second level electronic package, by reflowing the solder of the spacers using, for example, a conventional solder reflow oven. Then, the holder is dissolved, and washed away, in a conventional vapor degreaser using, for example, methylene chloride, to leave 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.