A printed circuit board structure includes a printed circuit board having a conductive structure, a dielectric structure and a copper foil layer. The copper foil layer has a first sub-copper foil layer and a second sub-copper foil layer on the printed circuit board. The dielectric structure and the first sub-copper foil layer have an opening. The opening exposes the conductive structure. A conductive bump is on the first sub-copper foil layer and in the opening, and the conductive bump is electrically connected to the conductive structure. A recess is between the first sub-copper foil layer and the second sub-copper foil layer, and the top surface of the second sub-copper foil layer is exposed. A method of forming the structure above is also provided.

Pastes are disclosed that are configured to coat a passage of a substrate. When the paste is sintered, the paste becomes electrically conductive so as to transmit electrical signals from a first end of the passage to a second end of the passage that is opposite the first end of the passage. The metallized paste contains a lead-free glass frit, and has a coefficient of thermal expansion sufficiently matched to the substrate so as to avoid cracking of the sintered paste, the substrate, or both, during sintering.

Pastes are disclosed that are configured to coat a passage of a substrate. When the paste is sintered, the paste becomes electrically conductive so as to transmit electrical signals from a first end of the passage to a second end of the passage that is opposite the first end of the passage. The metallized paste contains a lead-free glass frit, and has a coefficient of thermal expansion sufficiently matched to the substrate so as to avoid cracking of the sintered paste, the substrate, or both, during sintering.

Pastes are disclosed that are configured to coat a passage of a substrate. When the paste is sintered, the paste becomes electrically conductive so as to transmit electrical signals from a first end of the passage to a second end of the passage that is opposite the first end of the passage. The metallized paste contains a lead-free glass frit, and has a coefficient of thermal expansion sufficiently matched to the substrate so as to avoid cracking of the sintered paste, the substrate, or both, during sintering.

A wiring board, a multilayer wiring board, and a method of manufacturing a wiring board adapted to make the filling of through holes and the formation of fine wiring patterns. The wiring board comprises an insulator; a through hole between front and back surfaces of the insulator; a through hole conductor for electrically connecting front and back surface side openings; through hole lands around the front and the back surface side openings, and connected to the through hole conductor; lid plating conductors on the front and the back surface sides, and placed on the respective through hole lands; and wiring patterns formed on the front are compatible and the back surface of the insulator. The thickness of the through hole lands is 1.0 m or more and 10.0 m or less, and the area of each lid plating conductor is less than the area of each through hole land.

A coil coating method for multilayer coating of a continuous metal strip, which is disposed in the strip passage, in which on a flat side of the metal strip, a curable polymer primer is applied by means of a roller application and cured in order to form an electrically insulating primer layer and a curable polymer varnish is applied onto said primer layer by means of roller application and cured in order to form an electrically insulating varnish layer, wherein at least one at least electrically conductive conductor track is printed on at least some areas between the primer layer and the varnish layer is proposed. In order to increase the reproducibility of the coil coating method, it is proposed that the conductor track be printed on some areas of the pre-cured primer layer and that the conductor track and varnish be applied using a wet-on-wet process.

A fabrication process for soft-matter printed circuit boards is disclosed in which traces of liquid-phase GaIn eutectic (eGaIn) are patterned with UV laser micromachining (UVLM). The terminals of the elastomer-sealed LM circuit connect to the surface mounted chips through vertically-aligned columns of eGaIn-coated ferromagnetic microspheres that are embedded within an interfacial elastomer layer.

A filling method of conductive paste includes a step of providing a protective film on a principal surface of a metal foil clad laminated sheet, a step of forming bottomed via holes, a step of removing the film from a surface to a midway thereof to form a conductive paste flowing groove having the via holes, a step of disposing a housing member on the film, and thereby, causing a conductive paste injecting channel and a vacuum evacuating channel to communicate with a conductive paste flowing space S, a step of depressurizing the space S via the channel, and a step of injecting conductive paste into the space S via the channel, and thereby, filling an inside of the via holes with the conductive paste.

A substrate for mounting a semiconductor device includes an insulating layer having first and second opposed surfaces defining a thickness. First and second electrically conductive lands are included in the insulating layer. The first electrically conductive lands extend through the whole thickness of the insulating layer and are exposed on both the first and second opposed surfaces. The second electrically conductive lands have a thickness less than the thickness of the insulating layer and are exposed only at the first surface. Electrically conductive lines at the first surface of the insulating layer couple certain ones of the first electrically conductive lands with certain ones of the second electrically conductive lands. The semiconductor device is mounted to the first surface of the insulating layer. Wire bonding may be used to electrically coupling the semiconductor device to certain ones of the first and second lands.

A printed circuit board includes a first insulating layer; a connection via penetrating through at least a portion of the first insulating layer and having an upper surface exposed to an upper surface of the first insulating layer; a cavity penetrating through at least a portion of the first insulating layer and having the upper surface of the first insulating layer as a bottom surface of the cavity; a bridge disposed in the cavity and having a first bridge pad disposed on a lower side of the bridge; and a bonding layer including conductive particles connected to the connection via and the first bridge pad.