Abstract: Cleaning of a micromimiature high-density flip-chip assembly is carried out by spinning the assembly while applying cleaning fluid to a central portion of the assembly. Confinement of the cleaning fluid to a critical interconnection space of the assembly is ensured by a centrally apertured cover that resiliently engages the top of the assembly. During spinning, cleaning fluid is introduced through the aperture in the cover and is directed into and confined to flow radially in the interconnection space.

Abstract: The bottom and side surfaces of an electronic device, such as an integrated circuit chip or a multichip assembly, are surrounded by a soft gel medium. The gel medium is laterally confined by a rigid plastic rim that is epoxy-bonded in place along its perimeter. A plate, made of plastic or metal, can be attached to the top surface of the rim, in order to provide a cover for the package.

Abstract: A novel packaging of semiconductor elements, such as MCM tiles, with a variety of printed circuit or wired boards (PWB), the packages occupying a small size, at least in the vertical direction, relative to prior art OMPAC devices. The MCM tile includes an interconnection substrate with peripheral metallizations and at least one chip or integrated circuit (IC) mounted on the substrate by solder reflow or conductive adhesive technology. The PWB which may be a single level or a multilevel, is provided with an aperture for accommodation of at least one chip therein. Depending on the type of interconnection between the substrate and the PWB, the aperture may be larger than the substrate of the MCM tile for wire bonding interconnection or smaller than the substrate for solder reflow or conductive adhesive interconnection. In the wire bonding case, the MCM tile is positioned within the aperture resting on the surface of the PWB or of a structural member or of a heat sink which encloses one end of the aperture.

Abstract: A technique for monitoring the drawdown zone of an optical fiber preform is disclosed. The technique involves detecting the caustic rays emanating from the drawdown zone. Analysis of these rays allows one to determine the geometric properties of both the drawdown zone and the resultant optical fiber. In addition, detailed information concerning the index of refraction distribution in the fiber may be obtained. The process is amenable to realtime applications during the drawing of an optical fiber.