Abstract:
A multilayer printed circuit board including a substrate board and a built-up structure formed over the substrate board. The built-up structure includes conductor circuits and resin insulating layers. The built-up structure has via holes interconnecting the conductor circuits through one or more resin insulating layers. The via holes are filled up with plating, and the resin insulating layers is formed of a cycloolefin resin.
Abstract:
A printed wiring board having a through hole conductor formed on the surface of a through hole formed in a copper-clad laminate board, and on the surface of the copper-clad laminate board 1 in the vicinity of an opening of the through hole. The through hole conductor is filled with a positive photosensitive resin. A capped conductor is formed on the positive photosensitive resin and is coupled to the through hole conductor. Further, a circuit pattern is formed on the surface of the copper-clad laminate board. An insulating layer is formed on the surface of the copper-clad laminate board, capped conductor, and the circuit pattern, and formed with a via hole extending from the surface of the insulating layer to the capped conductor. A via conductor is formed inside the via hole and on the surface of the insulating layer in the vicinity of an opening of the via hole.
Abstract:
A package substrate free of malfunction or error even with an IC chip in a high frequency range, particularly an IC chip with a frequency exceeding 3 GHz, is provided. A conductor layer 34P on a core substrate 30 is formed to have a thickness of 30 μm and a conductor circuit 58 on an interlayer resin insulating layer 50 is formed to have a thickness of 15 μm. By making the conductor layer 34P thick, it is possible to increase a volume of the conductor itself and decrease resistance. Further, by employing the conductor layer 34 as a power supply layer, it is possible to improve a capability of supplying power to the IC chip.
Abstract:
The present invention provides a number of techniques for laminating and interconnecting multiple substrates to form a multilayer package or other circuit component. A solder bump may be formed on the conductive pad of at least one of two or more substrates. The solder bump preferably is formed from an application of solder paste to the conductive pad(s). Adhesive films may be positioned between the surfaces of the substrates having the conductive pads, where the adhesive films include apertures located substantially over the conductive pads such that the conductive pads and/or solder bumps confront each other through the aperture. The two or more substrates then may be pressed together to mechanically bond the two or more substrates via the adhesive films. The solder bump(s) may be reflowed during or after the lamination to create a solder segment that provides an electrical connection between the conductive pads through the aperture in the adhesive films.
Abstract:
A solder resist comprising a thermosetting resin is printed on a surface of an insulating board (7) having a conductor circuit (6). The solder resist is then heat-cured to form an insulating film (1) having a low thermal expansion coefficient. A laser beam (2) is then applied to the portion of the insulating film in which an opening is to be formed, to burn off the same portion for forming an opening (10), whereby the conductor circuit (6) is exposed. This opening may be formed as a hole for conduction by forming a metal plating film on an inner surface thereof. It is preferable that an external connecting pad be formed so as to cover the opening. The film of coating of a metal is formed by using an electric plating lead, which is preferably cut off by a laser beam after the electric plating has finished.
Abstract:
Methods for fabricating Land Grid Array (LGA) interposer contacts that are both conducting and elastic. Also provided are LGA interposer contacts as produced by the inventive methods. Provided is LGA type which utilizes a pure unfilled elastomer button core that is covered with an electrically-conductive material that is continuous from the top surface to the bottom surface of the button structure. In order to obviate the disadvantages and drawbacks which are presently encountered in the technology pertaining to the fabrication and structure of land grid arrays using electrically-conductive interposer contacts, there is provided both methods and structure for molding elastomer buttons into premetallized LGA carrier sheets, and wherein the non-conductive elastomer buttons are surface-metallized in order to convert them into conductive electrical contacts.
Abstract:
A solvent-free filling material comprising a filler, a thermosetting resin, a curing agent, and a curing catalyst, wherein the thermosetting resin is an epoxy resin, and the curing agent is a dicyandiamide curing agent; a multilayer printed wiring board comprising a substrate, a through-hole, the filling material filling the through-hole, and a conductor layer formed on an exposed surface of the filling material in the through-hole; and a process for producing the multilayer printed wiring board.
Abstract:
An opening is formed in resin 20 by a laser beam so that a via hole is formed. At this time, copper foil 22, the thickness of which is reduced (to 3 μm) by performing etching to lower the thermal conductivity is used as a conformal mask. Therefore, an opening 20a can be formed in the resin 20 if the number of irradiation of pulse-shape laser beam is reduced. Therefore, occurrence of undercut of the resin 20 which forms an interlayer insulating resin layer can be prevented. Thus, the reliability of the connection of the via holes can be improved.
Abstract:
An opening is formed in resin 20 by a laser beam so that a via hole is formed. At this time, copper foil 22, the thickness of which is reduced (to 3 μm) by performing etching to lower the thermal conductivity is used as a conformal mask. Therefore, an opening 20a can be formed in the resin 20 if the number of irradiation of pulse-shape laser beam is reduced. Therefore, occurrence of undercut of the resin 20 which forms an interlayer insulating resin layer can be prevented. Thus, the reliability of the connection of the via holes can be improved.
Abstract:
Closed vias are formed in a multilayer printed circuit board by laminating a dielectric layer to one side of a central core having a metal layer on each side. A second dielectric layer is laminated to the other side of the central core. Closed vias in the central core have been formed by drilling partially through but not completely penetrating the central core, and then completing the via from the opposite side with a hole that is much smaller in diameter to form a pathway that penetrates completely through the central core from one side to another. The via is then plated with metal to substantially close the smaller hole. Approximately one half of the closed vias are situated such that the closed aperture faces one dielectric layer and a remainder of the closed vias are situated such that the closed aperture faces the other dielectric layer. Resin from one dielectric layer fills the cavities of approximately one half of the closed vias, and resin from the other dielectric layer fills the circular cavities of the remainder of the closed vias. The total amount of resin migrated from each of the dielectric layers into the closed via cavities is approximately equal.