Abstract:
A semiconductor device-mounting construction including a semiconductor device having a plurality of electrodes formed on one main surface thereof. A printed circuit board having a writing pattern formed on one main surface thereof and a plurality of solder bumps interposed between the plurality of electrodes and the writing pattern to electrically connect the semiconductor device and the printed circuit board together. All of the voids, which are present in an interface of each of those of the plurality of solder bumps which are disposed closest to an outer peripheral edge of the semiconductor device, joined to the semiconductor device, are fine, and generally uniform in size.
Abstract:
A circuit board including a desired number of electrically insulating layers and wiring layers laminated alternately, and an inner via hole for securing an electrical connection between the wiring layers by compressing and hardening a conductive paste including a conductive particle and a resin. In the electrically insulating layer, a porous sheet is provided a resin sheet at least one surface, and the porous sheet is not impregnated with a resin at least at a central portion. A through hole penetrating the electrically insulating layer in the direction of the thickness of the electrically insulating layer is filled with a conductive paste including a conductive particle and a resin, and pores that are present inside the porous sheet are filled with laminated resin. The average hole diameter of the pores inside the porous sheet may be smaller than the average particle size of the conductive particle. Thereby, it is possible to make the insulating layer of the circuit board securing the interlayer electrically connection by an inner via hole including a conductive paste to be homogenized and ultra-thin and improve the reliability of the connection of the inner via hole.
Abstract:
A process for sealing a ceramic filter by infiltrating a metal into an end of the filter. The process includes the steps of contacting the end of a porous ceramic filter with a molten metal, whereby the metal enters into the ceramic matrix to substantially fill the void space. The ceramic filter is cooled to form a filter having a ceramic-metal composite portion. The present invention also provides a filter having an infiltrated metal seal. Methods for joining infiltrated ends are also provided.
Abstract:
A printed circuit board includes an uncured substrate material with closed voids which are disposed with a through-hole. When the through-hole is formed, voids which exist in the substrate material open from inner wall of the through-hole to form a hollow-shaped part. By filling the through-hole and the hollow-shaped part with conductive paste, the adhesion improves by the increased holding effect between the conductive paste and the wall surface of the through-hole.
Abstract:
Apertures in a tape formed on a substrate allow straight plating of solder bumps to heights above 4 mils. The solder bumps are combined with a lower density material to form an hourglass-shaped structure which allows interconnections to bonding pads of electronic components with pitches less than 9 mils.
Abstract:
A polymeric three-layer membrane having metal-filled microscopic pores extending through the complete thickness of the membrane, including a central restraining core layer, and an adhesive layer on each surface of the core layer. The membrane is used to form interconnects between electronic parts.
Abstract:
A method and apparatus for cooling electrical components on a substrate during a rework process. A block of a porous, thermally conductive material, saturated with a liquid, is positioned on an electrical component to be cooled. During the rework processing of an adjacent electrical component, the liquid in the porous, thermally conductive block vaporizes, thereby maintaining the temperature of the electrical component below its reflow temperature. A second thermally conductive block, in thermal contact with the porous, thermally conductive block, and the substrate on which the electronic component to be cooled is attached, is positioned between the electronic component to be cooled and the electronic component undergoing rework. A supply of liquid is provided to the porous, thermally conductive block to maintain the temperature of the electronic component to be cooled at a predetermined level for a specified period of time.
Abstract:
The present invention provides a printed circuit substrate comprising a lightweight prepreg and a conductive layer. The prepeg having uniform formation, low linear thermal expansion coefficient and good mechanical strength, comprising a porous para-oriented aromatic polyamide film and a thermoplastic resin and/or a thermosetting resin, the porous para-oriented aromatic polyamide film being impregnated with the thermoplastic resin and/or the thermosetting resin, a process for producing the same, and a printed circuit substrate/board using the same.
Abstract:
Apertures in a tape formed on a substrate allow straight plating of solder bumps to heights above 4 mils. The solder bumps are combined with a lower density material to form an hourglass-shaped structure which allows interconnections to bonding pads of electronic components with pitches less than 9 mils.