After a copper plate 14 is bonded to at least one surface of a ceramic substrate 10 via an active metal containing brazing filler metal 12 which contains silver, the unnecessary portion of the copper plat 14 and active metal containing brazing filler metal 12 is removed, and thereafter, an unnecessary portion of the copper plate 14 is removed by chemical polishing so as to cause the active metal containing brazing filler metal 12 to protrude from the side face portion of the copper plate 14, and then, a silver layer 18 adhered to the surface of the copper plate 14 by the chemical polishing is removed.

A ceramic circuit board includes an insulating substrate composed of stacked insulating layers of an alumina-based sintered body, internal leads containing Cu embedded in the insulating substrate, and one or a plurality of metal layers containing Cu embedded in the insulating substrate, at least one of the metal layers being located nearer than the internal leads to the surface of the insulating substrate in the stacking direction, wherein at least part of the metal layer overlaps the internal leads in plan view.

A process of improving resistance to conductive anodic filament (CAF) formation is disclosed. The process includes dissolving a base resin material, a lubricant material, and a coupling agent in a solvent to form a functionalized sizing agent solution. The process also includes applying the functionalized sizing agent solution to individual glass fibers following a glass fiber formation process. The process further includes removing the solvent via a thermal process that partially converts the base resin material. The thermal process results in formation of coated glass fibers having a flowable resin coating that is compatible with a pre-impregnated (prepreg) matrix material utilized to form a prepreg material for manufacturing a printed circuit board. During one or more printed circuit board manufacturing operations, the flowable resin coating flows to fill voids between the individual glass fibers that represent CAF formation pathways.

In order to improve the strength and elongation of a solder and improve the reliability of a joining portion joined by the solder, the present invention provides a solder alloy that comprises 2.0-4.0 mass % of Ag, 0.5-1.0 mass % of Cu, 0.1-1.0 mass % of Sb, 0.1-0.5 mass % of an additive element selected from the group consisting of Ca, Mn, and Al, and a balance of Sn.

A surface finish may be formed in a microelectronic structure, wherein the surface finish may include an interlayer comprising a refractory metal, phosphorus, and nickel, with the refractory metal having a content of between about 2 and 12% by weight and the phosphorus having a content of between about 2 and 12% by weight with the remainder being nickel. In one embodiment, the refractory metal of the interlayer may consist of one of tungsten, molybdenum, and ruthenium. In another embodiment, the interlayer may comprise the refractory metal being tungsten having a content of between about 5 and 6% by weight and phosphorus having a content of between about 5 and 6% by weight with the remainder being nickel.

The invention relates to a process for forming a cobalt-iron alloy film. In particular, the process is performed under ultrasonic vibrations to form the cobalt-iron alloy film. The cobalt-iron alloy film consists of about 75-95 wt. % of cobalt, 4.5-20 wt. % of iron and 0.5-5 wt. % of phosphorus and also has peaks at about 43.2, 45.1, 50.4, 65.5, 74.1 and 83.2 2-theta degree (2) in the X-ray diffraction pattern.

This application provides a circuit board, an electronic device, and a production method for a circuit board. The circuit board includes: a board body; an electronic component, welded to a surface of the board body by using soldering tin; and a reaction particle, disposed on the surface of the board body and adjacent to a weld leg for welding the electronic component. When the circuit board is energized and in an environment with water, the reaction particle reacts with the weld leg to form an insoluble protection layer on an outer surface of the weld leg, and the insoluble protection layer isolates the weld leg from water to prevent dendrite corrosion of the weld leg.

A printed wiring board includes a first conductor layer including a first conductor circuit and a second conductor circuit formed adjacent to the first circuit, a resin insulating layer formed on the first conductor layer such that the insulating layer is filling space between the first and second conductor circuits, and a second conductor layer formed on the insulating layer such that distance (T) between the first and second conductor layers is in the range of 4.5 m to 10.5 m. The resin insulating layer includes inorganic particles having average particle diameter (D1) such that ratio (D1/S) of the diameter (D1) to distance (S) of the space is less than 0.25 and that ratio (D1/T) of the diameter (D1) to the distance (T) is less than 0.25, where the distance (S) of the space between the first and second conductor circuits is in the range of 4.5 m to 10.5.

A nanocomposite coating composition for use in the mitigation of whisker growth from a metallic surface (82) includes a polymer matrix (86) comprising a base polymer and insulating material nanoplatelets (85), for example clay nanoplatelets, within the polymer matrix (86). A conformal coating (84) for application to a metal surface (82) is formed from the coating composition. The conformal coating mitigates the spontaneous growth of whiskers (83), in particular tin whiskers, from the coated surface (82), reducing the risk of short-circuits caused by such whiskers bridging gaps within electronic devices. Methods are provided for the preparation of coating compositions and coatings.

The wiring board of the present disclosure includes an insulating layer, and a wiring conductor existing so as to be adjacent to both main surfaces of the insulating layer; the insulating layer includes at least two particle-containing resin layers containing insulating particles in an insulating resin, and a particle-free resin layer formed of an insulating resin; and the particle-free resin layer is interposed between the particle-containing resin layers.