Abstract: A chip stack comprising a flex circuit which itself comprises a flexible substrate having opposed, generally planar top and bottom surfaces. Disposed on the top surface of the substrate in spaced relation to each other are at least first and second top conductive patterns. Similarly, disposed on the bottom surface of the substrate in spaced relation to each other are at least first and second bottom conductive patterns. The first top and bottom conductive patterns are electrically connected to each other, as are the second top and bottom conductive patterns. At least one top chip package including a first packaged chip is electrically connected to the first top conductive pattern, with at least one bottom chip package including a second packaged chip being electrically connected to the second bottom conductive pattern. The substrate is folded such that the second top conductive pattern is electrically connected to the top chip package.

Abstract: A retaining ring interconnect. A retaining ring is formed on a perimeter of a pad on each of two adjoining surfaces of two PCB substrates. A conductive paste is applied between the pads on the two adjoining surfaces. The retaining rings are aligned and facing with each other. By performing a heat compression process, the retaining rings are connected to encompass the conductive paste. A eutectic bond is thus formed to bond the two PCB substrates.

Abstract: A chip stack comprising at least two base layers, each of which includes a base substrate and a first conductive pattern disposed on the base substrate. The chip stack further comprises at least one interconnect frame having a second conductive pattern disposed thereon. The interconnect frame is disposed between the base layers, with the second conductive pattern being electrically connected to the first conductive pattern of each of the base layers. Also included in the chip stack are at least two integrated circuit chips which are electrically connected to respective ones of the first conductive patterns. One of the integrated circuit chips is at least partially circumvented by the interconnect frame and at least partially covered by one of the base layers. The chip stack further comprises a transposer layer comprising a transposer substrate having a third conductive pattern disposed thereon.

Abstract: A stackable flex circuit IC package includes a flex circuit comprised of a flexible base with a conductive pattern thereon, and wrapped around at least one end portion of a frame so as to expose the conductive pattern at the edge portion. An IC device is mounted within a central aperture in the frame, and is electrically coupled to the conductive pattern. The IC device is sealed in place within the frame with epoxy. A stack of the IC packages is assembled by disposing a conductive epoxy of anisotropic material between the conductive patterns at the edge portions of adjacent IC packages. Application of pressure in a vertical or Z-axis direction between adjacent IC packages completes electrical connections between the individual conductors of the conductive patterns of adjacent IC packages to interconnect the IC packages of the stack, while at the same time maintaining electrical isolation between adjacent conductors within each of the conductive patterns.

Abstract: A chip module comprising a chip array which includes an interconnect substrate having opposed, generally planar surfaces and a first interconnect pad array disposed on at least one of the surfaces thereof. Attached to the interconnect substrate is at least one integrated circuit chip of the chip array which is electrically connected to the first interconnect pad array. The chip module further comprises a package which itself comprises a main body defining a cavity sized and configured to receive the chip array and having a generally planar interconnect shelf which extends within the cavity and includes a second interconnect pad array disposed thereon. The package also includes a lid which is attachable to the main body. The chip array is insertable into the cavity such that the first and second interconnect pad arrays are in aligned contact with each other and the attachment of the lid to the main body encloses and seals the chip array within the package.

Abstract: A method of making chip stacks begins with the formation of a plurality of panels having apertures therein and conductive pads on opposite sides thereof. Solder paste is deposited on the conductive pads prior to mounting plastic packaged IC chips within each of the apertures in each of the panels so that opposite leads thereof reside on the conductive pads at opposite sides of the apertures. The plural panels are then assembled into a stack, such as by use of a tooling jig which aligns the various panels and holds them together in compressed fashion. The assembled panel stack is heated so that the solder paste solders the leads of the packaged chips to the conductive pads and interfacing conductive pads of adjacent panels together, to form a panel stack comprised of a plurality of chip package stacks. Following cleaning of the panel stack to remove solder flux residue, the individual chip package stacks are separated from the panel stack by cutting and breaking the stack.

Abstract: An integrated circuit chip stack includes a stack of chip packages mounted on a substrate. Each chip package includes a plastic packaged chip mounted within a central aperture in a thin, planar frame by soldering leads at opposite ends of the plastic package to conductive pads on an upper surface of the frame adjacent the central aperture. Conductive traces and vias couple the conductive pads to other conductive pads on upper and lower surfaces of the frame adjacent outer edges thereof. The conductive pads adjacent the outer edges are soldered to the conductive pads of adjacent chip packages by dipping the edges of an assembled stack of the chip packages in solder. The chip stack thus formed is mounted on a substrate. Each chip package can be individually addressed by the substrate, such as to enable the chip therein, using a stair step arrangement of the conductive pads in which the pads on the opposite surfaces of each frame are coupled in offset fashion by vias extending through the frame.

Abstract: An IC chip package includes a chip having an upper active surface thereof bonded to the lower surface of a substrate. A plurality of terminals on the active surface are wire bonded within the outer periphery of the chip by bonding wires extending through a plurality of apertures in a lower layer of the substrate to bonding pads on an upper surface of the lower substrate layer. Metallized strips couple the bonding pads to conductive pads at the outer edges of the lower substrate layer. The substrate includes an upper layer having apertures therein. After wire bonding, the apertures in the upper and lower substrate layers are filled with epoxy which is cured and then ground flush with the upper surface of the upper substrate layer. The chip is then lapped to a desired thickness, following which the chip package is electrically tested at various temperatures.

Abstract: A device for increasing the density of integrated circuit chips on a printed circuit board. A plurality of integrated circuits are packaged within chip carriers and stacked, on one top of the other, on a printed circuit board. Each of the input/output data terminals, power and ground terminals of the chips are connected in parallel. Each chip is individually accessed by selectively enabling the desired chip.