Abstract: An integrated circuit package for EPROM, CCD, and other optical integrated circuit devices has a substrate base having metallized vias extending there through. An integrated circuit die is affixed to a first surface of the substrate, and is electrically connected to the metallized vias. An adhesive bead is applied onto the substrate around the die. The bead covers the side surfaces of the die, the periphery of the upper first surface of the die, and the bond wires. The bead and the upper first surface of the die form a cavity above the die. A layer of a transparent encapsulating material is deposited onto the die, within the cavity formed by the bead. The encapsulating material is hardened, and subsequently forms an exterior surface of the package. The transparent encapsulating material allows light of a selected frequency to illuminate the light sensitive circuitry of the die.

Abstract: A mounting for a flip chip integrated circuit device having a light sensitive cell is disclosed. The mounting includes an insulating substrate having an aperture between its first and second surfaces. A flip chip integrated circuit device is placed on the first surface of the substrate. A light sensitive cell of the integrated circuit device faces the aperture. Solder bumps on the integrated circuit are electrically connected to corresponding conductive metallizations on the first surface of the substrate. A transparent aperture cover is affixed to the second surface of the substrate with an adhesive bead. The aperture cover extends over the aperture, allowing light to be transmitted through the aperture cover to the light sensitive cell. The side surfaces of the aperture cover include features for locking the adhesive bead to the aperture cover.

Abstract: A package for an integrated circuit is described, as is a method of making the package. An exemplary method of making a package for an integrated circuit die includes a first step of providing an insulating substrate having a substantially planar first surface. A conductive path extends through the substrate. Step two of the method places an integrated circuit die, such as an EEPROM or a CCD or SAW integrated circuit die, on the first surface of the substrate. Step three electrically connects the integrated circuit die to the conductive path. Step three applies an imperforate bead of a viscous adhesive material on the first surface of the substrate around the die. The bead extends to a height above the first surface of the substrate greater than the height of the integrated circuit die. Step four provides a lid having a first surface.

Abstract: A package for surface acoustical wave (SAW) device includes an electrically insulative substrate having a first surface with an electrically conductive layer formed thereon. A first surface of the SAW device is attached to the electrically conductive layer. An electrically conductive adhesive bead overlies the substrate first surface and surrounds the SAW device. An electrically conductive lid defines a free space over a second surface of the SAW device, the lid being electrically connected to the electrically conductive layer by the adhesive bead and one or more tabs extending from the lid through the adhesive bead to the electrically conductive layer. The electrically conductive adhesive bead, electrically conductive layer and electrically conductive lid enclose and shield the SAW device.

Abstract: A mounting for a semiconductor integrated circuit device, such as a charge coupled device ("CCD") or an erasable programmable read only memory device ("EPROM"), includes an insulating substrate having an aperture between its first and second surfaces. A first surface of the integrated circuit device is placed adjacent to and facing the first surface of the substrate. Light sensitive circuitry on the first surface of the integrated circuit device is aligned with the aperture. Solder bumps on the periphery of the first surface of the integrated circuit are electrically connected to corresponding conductive metallizations on the first surface of the substrate. A aperture cover transparent to light is affixed to the second surface of the substrate and extends over the aperture, so that light may be transmitted through the aperture cover and aperture to the light sensitive circuitry on the first surface of the integrated circuit device. The substrate may be a printed circuit board.

Abstract: An improved interconnection ball joint for a ball grid array integrated circuit package includes a substrate base having a first surface to which an integrated circuit die is affixed, and an opposite second surface. A metallized via extends through the substrate. The via has a central hole which extends through the substrate. The hole is plugged with a flexible nonconductive material, such as epoxy solder mask material. A metallic interconnection ball land is on the second surface of the substrate, integral with the metallized via and adjacent to the hole and the plug of nonconductive material. A solder interconnection ball is formed on the land, opposite the via and the plug of nonconductive material. A metal-to-metal annular bond is formed at the joint between the interconnection ball and the land around the plug of nonconductive material in the center of the via.

Abstract: Two interdigitated comb-shaped fixed voltage buses such as a power bus and ground bus, in the form of metallization are provided substantially encircling of an integrated circuit die in an integrated circuit package or other integrated die assembly. Any selection of bonding pads on the die and metallization leads in the assembly may be connected to the fingers of either bus. The length of wire bond or TAB connections and the area occupied by the buses is minimized by the interdigitated geometry of the buses.

Abstract: A heat spreader with one or more integrally formed open regions discourages the formation of air bubbles in the encapsulant of a plastic packaged integrated circuit. Little or no air bubbles can be trapped between the heat spreader and the encapsulant surface. Any air bubbles that do form in the encapsulant can escape through the open regions of the heat spreader. The heat spreader of the invention is placed on the surface of a liquid encapsulant and the encapsulant fills the open regions of the heat spreader and covers the sides of the open regions. When the encapsulant hardens, a form fitting bond between the heat spreader and the upper surface of the encapsulant is created. This form fitting bond provides for secure attachment of the heat spreader to the surface of the encapsulant. One embodiment of the heat spreader of the invention includes integrally formed tabs with which a supplementary heat spreader, such as heat tower, is inserted for even greater heat dissipation capability.

Abstract: A method and apparatus for applying flux to a series of metallization contacts or plated contact pad a substrate exposed by an apertured solder mask, employs a compressible transfer pad. A central flux pick-up area is formed on the transfer pad bottom surface. The bottom surface may be spherical and may include a cylindrical post onto which a predetermined amount of flux is transferred, such as by dipping the pick-up area into a reservoir of semi-liquid paste flux. The transfer pad is then positioned over and compressed on the solder mask such that the picked up flux on the flux pick-up area of the transfer pad is pressure forced by compression of the transfer pad through apertures in the solder mask directly and successively into all the series of depressions formed on the substrate until all the depressions are substantially filled with flux.

Abstract: A method for soldering the underside of a substrate between leads. A paste of solder emulsified in a flux material is printed onto a carrier and film. The paste is adhered to the film by drying or reflowing before being placed onto the substrate between the projecting leads. The substrate and film are then heated. The molten solder having an affinity for plated surface areas of the substrate and no affinity for the polyimide film transfers and self-aligns to the plated surfaces of the substrate. The method allows selective soldering of the underside surface of a substrate having leads without soldering these leads, or selective soldering of some plated areas of a substrate while leaving other plated areas free of solder.