Abstract: There is provided a ball grid array package for housing semiconductor devices. The package has a metallic base with conductive vias extending through holes formed in the base. The conductive vias terminate adjacent an exterior surface of the base. A dielectric coating on at least part of the base and through hole walls electrically isolates the metallic base from the package circuitry.

Abstract: The bending of a ball grid array electronic package having a metallic base is reduced minimizing stresses applied to the innermost row of solder balls when the package base is cyclically heated and cooled. Reducing the stresses applied to the solder balls increases the number of thermal cycles before solder ball fracture causes device failure. Among the means disclosed to reduce the bending moment are a bimetallic composite base, an integral stiffener, a centrally disposed cover bonded to an external structure and a package base with a stress accommodating depressed portion.

Abstract: A semiconductor package is provided that has a rigid metal substrate and a dielectric layer covering a first portion of the rigid metal substrate, with a second portion of the rigid metal substrate being substantially free of the dielectric layer. A semiconductor device is electrically bonded to the second portion of the rigid metal substrate and metal circuit traces defining electrical paths are formed on the dielectric layer, at least one of which contacts the rigid metal substrate through at least one via in the dielectric layer. Additionally, a method is provided for grounding a semiconductor device and at least one circuit trace on a rigid metal substrate substantially covered by a dielectric layer, which includes creating at least one via in the dielectric layer using a laser and creating circuit traces on the dielectric layer, at least one of which contacts the rigid metal substrate through at least one of the vias.

Abstract: A surface mount package to encapsulate one or more semiconductor devices has a standoff that maintains the thickness of solder columns bonding the package to an external circuit. The standoff either extends over or circumscribes a central portion of the package base. To enhance the thermal performance of the standoff, a solderable layer enhances soldering of the standoff to the external circuit.In alternative embodiments, the standoff contains a flange having a plurality of apertures useful for either mechanically locking an adhesive or for enabling irradiation of an adhesive by a light source. The standoff may contain protrusions for alignment, strength or circuit routing.

Abstract: There is provided a component for an electronic package and a method for the manufacture of that component. The component has a metallic substrate with a surface coated by a dielectric. A centrally disposed cavity extends through the dielectric into the metallic substrate to a depth, D.sub.1. Circumscribing and abutting this cavity is an annular channel having a depth D.sub.2 that is less than D.sub.1. A semiconductor device bonded to the base of the cavity is electrically interconnected to both circuit traces formed on the dielectric coating and to the annular channel.A method of forming the annular channel is to mechanically mill a precursor annular channel having an outer wall a desired distance from the sidewalls of the metallic substrate and a width substantially greater than the desired width of the annular channel. A cavity is then formed in the region circumscribed by the outer wall of the precursor annular channel.

Abstract: There is disclosed components for electronic packaging applications having integral bumps. A leadframe is formed by etching a metallic strip from one side to form outwardly extending, substantially perpendicular integral bumps. The metallic strip is then etched from the opposite side to form individual leads. When the integrally bumped component is an package base, fatigue of solder balls is reduced.

Abstract: There is provided a metallic component for an electronic package. The component is coated with an electrically non-conductive layer and has a plurality of conductive circuit traces are formed on a surface. The circuit traces are soldered directly to the input/output pads of an integrated circuit device and to a second plurality of circuit traces. The component may include a heat sink to enhance dissipation of heat from an encapsulated integrated circuit device.

Abstract: There is provided a leadframe having a plurality of coplanar electrically conductive leads. At least one metallic guard is bonded to the leads with a dielectric layer disposed between the metallic guard and the leads. The metallic guard has good adhesion to a polymer molding resin such that when the leadframe structure is encased in a molding resin, delamination is minimized. By restricting delamination, the ingress of water and water soluble contaminants to an integrated circuit device is inhibited.

Abstract: There is provided a base for an electronic package. The base includes a peripheral portion for a polymer adhesive and a central portion for one or more semiconductor devices. A lead support is adjacent the substrate and located between the peripheral portion and the central portion. When a polymer adhesive bonds a leadframe to the package base, the lead support prevents deflection of the inner lead tips.

Abstract: There are provided polymer plugs for sealing the vent hole of an adhesively sealed electronic package. The polymer vent hole plug is selected to be either an ultraviolet curable polymer or a thermosetting polymer resin. One effective vent hole plug is a cylindrical plug having a diameter under 1.4 millimeters formed from a UV-curable epoxy.

Abstract: There is disclosed an adhesively sealed electronic package in which a compensation apparatus is provided for excess adhesive. As a result, excess adhesive does not extend beyond the package perimeter, squeeze-out, or travel along the inner lead fingers interfering with wire bonding. The compensation is a chamfer on the peripheral edges and/or interior edges of the package base component and cover component.

Abstract: An electronic package with a semiconductor chip, a lead frame, a metal casing, and a redistribution interposer. The chip is mounted on the interposer and wirebonded to first ends of redistribution leads of the interposer. The redistribution leads have second ends orientated in a general flipped orientation relative to their corresponding first ends. The second ends are wirebonded to pads of the lead frame. The interposer allows smaller chips to be used in the package without changing the lead frame. The interposer also allows the chip to be flip-mounted in the package without changing the lead frame or casing, this allows redirection of the chip's thermal path.

Abstract: There is provided an electronic package where the package components define a cavity. A semiconductor device and a portion of a leadframe occupy part of the cavity. Substantially the remainder of the cavity is filled with a compliant polymer, such as a silicone gel. Since the cavity is no longer susceptible to gross leak failure, the seal width of adhesives used to assemble the package may be reduced, thereby increasing the area available for mounting the semiconductor device.

Abstract: There is provided a module for supporting a plurality of semiconductor devices within an electronic package. The module has a support substrate and an apertured substrate laminated together with a polymer adhesive. A plurality of semiconductor devices are disposed within apertures formed in the apertured substrate and bonded to the support substrate by that same polymer adhesive.

Abstract: There is provided an electronic package where the package components define a cavity. A semiconductor device and a portion of a leadframe occupy part of the cavity. Substantially the remainder of the cavity is filled with a compliant polymer, such as a silicone gel. Since the cavity is no longer susceptible to gross leak failure, the seal width of adhesives used to assemble the package may be reduced, thereby increasing the area available for mounting the semiconductor device.

Abstract: A pearlescent pigment comprising a platelet-shaped substrate coated with titanium dioxide, an oxide of copper, and optionally oxides of aluminum, and/or zinc, whereby the pigment is silver-gray.

Abstract: There is provided an electronic package assembly having a die attach paddle bonded to the package base by a compliant adhesive. A recessed channel formed in the base is partially overlapped by the die attach paddle. During package sealing, excess adhesive accumulates in the recessed channel, eliminating bridging of the adhesive to the leadframe.

Abstract: A system for testing chips uses a patterned tape having a patterned array of cantilevered contact leads. The tape serves as an interface between the chip under test and a testing unit by providing conductive leads from the I/O terminals on the chip to an off-chip measuring system. The leads on the array may have balls, tips or other shapes on the end to provide contact with the terminals and compensate for height differences. The tape is a single frame or has a series of arrays each positioned around an opening where the chip will be located when a particular pattern is positioned over that chip for test. The pattern on the tape may be the same array or a different array. The tape is indexed to a new pattern when the old one is damaged or no longer needed. Alignment with the chip is by optical sensing and physical pin movement. The tape may have a flap protruding into an aperture and deflectable to provide for planar contact of the leads to the device under test.

Abstract: Playing cards are marked with binary codes adjacent both side edges of the face of each card in a standard deck. The code includes a precode which signals a card reader to read the code in proper bit sequence depending on the direction of card movement past the reader. The binary code includes six bits to represent face value and suit of the card, and a four-bit error detection code which can detect errors of two bits in the code.A deck of coded cards is dealt either manually or automatically according to at least one predetermined program. The coded cards are passed over photocells which read the binary codes on the face of the card. The photocell outputs are sent to a microprocessor, which compares the code to the predetermined program and directs the card to the appropriate player location.

Abstract: An improved floppy disc drive, with direct disc rotational drive, characterized by a step motor having a plurality of pole pairs with pole pieces fabricated from a portion of the drive housing at predetermined locations, and a disc having radial webs and positioned so that pairs of such radial webs align one pair at a time with successive ones of successively energized pole pairs, thereby providing a highly efficient and compact disc drive motor. The drive assembly also contains a read head drive with a step motor and transmission means for driving the read head radially with respect to the floppy disc. Means are provided which enable clutch operation to engage the disc with the drive only when the disc is properly seated within the drive assembly.