Abstract:
The present invention has for its object to provide a process for manufacturing multilayer printed circuit boards which is capable of simultaneous via hole filling and formation of conductor circuit and via holes of good crystallinity and uniform deposition can be constructed on a substrate and high-density wiring and highly reliable conductor connections can be realized without annealing. The present invention is related to a process for manufacturing multilayer printed circuit boards which comprises disposing an interlayer resin insulating layer on a substrate formed with a conductor circuit, creating openings for formation of via holes in said interlayer resin insulating layer, forming an electroless plated metal layer on said interlayer resin insulating layer, disposing a resist thereon, performing electroplating, stripping the resist off and etching the electroless plated metal layer to provide a conductor circuit and via holes, wherein the electroplating is performed intermittently using said electroless plated metal layer as cathode and a plating metal as anode at a constant voltage between said anode and said cathode.
Abstract:
An apparatus includes an electronic component mounted on a substrate and metal conductors electrically connecting the electronic component. A conformal coating overlies the metal conductors and comprises a polymer into which a phosphine compound is impregnated and/or covalently bonded. Accordingly, the conformal coating is able to protect the metal conductors from corrosion caused by sulfur components (e.g., elemental sulfur, hydrogen sulfide, and/or sulfur oxides) in the air. That is, the phosphine compound in the polymer reacts with any corrosion inducing sulfur component in the air and prevents the sulfur component from reacting with the underlying metal conductors. Preferably, the phosphine compound in the polymer does not react with other components in the air (e.g., carbon dioxide) which would otherwise deplete its availability for the target reaction. The phosphine compound may be rendered completely non-volatile by covalently bonding it directly into the polymer backbone.
Abstract:
A circuit board includes a substrate, a circuit pattern and a through electrode. The circuit pattern is disposed on one side of the substrate in a thickness direction thereof. The through electrode is filled in a through-hole formed in the substrate with one end connected to the circuit pattern. The circuit pattern and the through electrode each have an area containing a noble metal component (e.g., Au component) and are connected to each other therethrough.
Abstract:
Provided is metal-containing resin particle for forming a conductor pattern in which the metal particles are dispersed in a resin matrix, and the content of the metal particles is 70 wt % or less.
Abstract:
A substrate for embodying multi-package comprises an underlying layer has a polymer material containing a conductive filler and provided with a step-like groove divided into step part and bottom part; a coating layer formed over the underlying layer, the coating layer is formed so that it may define a metal-wire forming area on the step part and the bottom part of the step-like groove and the conductive filler in the metal-wire forming area is exposed; and a metal wire formed via a plating process using the exposed conductive filler in the metal-wire forming area defined by the coating layer as a seed layer.
Abstract:
Briefly, a novel material process is disclosed wherein one or more nucleation modifiers are added, in trace amounts, to a lead-free tin-rich solder alloy to produce a solder composition with reduce or suppressed undercooling temperature characteristics. The modifier being a substance which facilitates the reduction of extreme anisotropic properties associated with body-centered-tetragonal tin based lead-free solder. The addition of the nucleation modifiers to the solder alloy does not materially effect the solder composition's melting point. As such, balls of solder with the nucleated composition freeze while other solder balls within the array remain in the melt. This effectively enables one substrate to be pinned to another substrate by one or more predetermined solder balls to secure the package while the remaining solder joints are in the liquid state. Further, the addition of a trace amount of nucleation sites within the composition facilitates control over the number, size, and orientations of primary intermetallic compounds in tin rich crystallite grains. Moreover, trace amounts of one or more solid and/or insoluble nucleating modifiers within a given volume of solder reduces the size of average crystallites within the composition.
Abstract:
Briefly, a novel material process is disclosed wherein one or more nucleation modifiers are added, in trace amounts, to a lead-free tin-rich solder alloy to produce a solder composition with reduced or suppressed undercooling temperature characteristics. The modifier being a substance which facilitates the reduction of extreme anisotropic properties associated with body-centered-tetragonal tin based lead-free solder. The addition of the nucleation modifiers to the solder alloy does not materially effect the solder composition's melting point. As such, balls of solder with the nucleated composition freeze while other solder balls within the array remain in the melt. This effectively enables one substrate to be pinned to another substrate by one or more predetermined solder balls to secure the package while the remaining solder joints are in the liquid state.
Abstract:
An electronic component having a semiconductor element bonded to a substrate with solder has a decreased bonding strength if there is not a suitable clearance between the semiconductor element and the substrate. Therefore, a solder preform having high melting point metal particles dispersed in solder has been used in the manufacture of electronic components. However, when an electronic component was manufactured using a conventional solder preform, there were cases in which the semiconductor element leaned or the bonding strength was not adequate.A solder preform according to the present invention has a variation in the size of high melting point metal particles which is at most 20 micrometers when the metal particle diameter is 50 micrometers, and an alloy layer of the high melting point metal particles and the main component of solder is formed around the high melting point metal particles. In addition, no voids at all are present in the solder. An electronic component according to the present invention has a semiconductor element bonded to a substrate with the above-described solder preform and has excellent resistance to heat cycles.
Abstract:
There are disclosed insulated ultrafine powder comprising electroconductive ultrafine powder which is in the form of sphere, spheroid or acicular each having a minor axis in the range of 1 to 100 nm and an insulating film applied thereto; a process for producing the same which is capable of covering the surfaces of the insulated ultrafine powder with the insulating film having a thickness in the range of 0.3 to 100 nm without causing any clearance or vacancy; and a resin composite material which uses the same. A high dielectric constant of the material is assured by adding a small amount of insulated ultrafine powder wherein an insulating film is applied to the electroconductive ultrafine powder, while maintaining the processability and moldability that are the characteristics inherent in a resin material.
Abstract:
A printed circuit board (PCB) includes a base substrate, an electrical wiring, a dummy pad and a thermally conductive adhesion member. The base substrate includes a light-emitting diode (LED) mounted on a first surface of the base substrate. The electrical wiring is electrically connected to the LED. The dummy pad is formed on the first surface to be connected to the electrical wiring. The thermally conductive adhesion member is attached to a second surface of the base substrate. Therefore, superior heat radiation may be obtained, thereby reducing or preventing damage to the LED and the LCD device using the LED by radiating the heat from the LED used as a light source.