The application provides a printed circuit board and an optical module so as to alleviate poor contact between the electro-conductive contact sheet group and the clamping piece due to the solder resist. The printed circuit board includes a substrate, and electro-conductive contact sheet group positioned on the surface of the substrate, where a part of the substrate is overlaid with solder resist, and there is a gap between the solder resist and the electro-conductive contact sheet group.

A PCBA for use in a high-energy broadband electric field includes a low-voltage power supply and alternating conductive and dielectric layers. An outermost one of the conductive layers includes a dielectric surface switch having closely-spaced switch contacts. The first switch contact is connected to the positive terminal and the second switch contact is connected to the negative terminal. Vias connect the conductive layers to the terminals through the respective first and second switch contacts to form power and ground planes. A metamaterial layer of nickel is doped with up to 20 percent phosphorus or chromium by weight, has a uniform thickness of less than 5 m, is sandwiched between interfacing surfaces of a pair of the conductive and dielectric layers, and evenly coats one of the interfacing surfaces. A sonobuoy system includes the PCBA, e.g., an Electronic Function Select board, a cylindrical housing, and an acoustic array.

A method of fabricating a composite conductive film is provided. The method includes providing, as a matrix, a layer of photoresist material. The method further includes introducing a plurality of inorganic particles upon a surface of the layer of photoresist material. The method further includes, without patterning the layer of photoresist material, embedding at least some of the plurality of inorganic particles into the layer of photoresist material to form an inorganic mesh within the layer of photoresist material, thereby forming the composite conductive film. Embedding at least some of the plurality of inorganic particles into the layer of photoresist material results in the composite conductive film being patternable and substantially transparent to optical light.

A circuit assembly (200) is disclosed comprising a substrate (210) and conducting layers (250) on opposing sides of the substrate (210), there being at least one via (220) through the substrate (210), which via (220) forms a conductive path between the conducting layers, wherein the substrate (210) is a foam substrate, and wherein the via (220) is provided with a solid dielectric lining (270) plated with a conducting material (250).

A process for manufacturing a flexible cellulosic substrate comprises at least one functional circuit and/or at least one functional board. The flexible cellulosic substrates are made functional by printing with a functional ink, which provides good performance (signal speed/dielectric properties of the substrate), is economical, thermally and dimensionally stable, and is able to be produced simply and reproducibly at an industrial rate. The process starts with an aqueous fibrous suspension comprising paper pulp and/or a pulp of (micro/macro) cellulose fibrils and produces a wet fibrous mat from this suspension. One of the faces of the wet fibrous mat is printed by means of at least one functional ink capable of transmitting, emitting, and/or processing at least one signal in order to produce at least one topography comprising at least one track for circulation of the signal. Printed circuits and functional boards are obtained by the manufacturing process.

A method of fabricating a composite conductive film is provided. The method includes providing, as a matrix, a layer of cross-linkable polymer while the cross-linkable polymer is in a substantially noncross-linked state. The method further includes introducing a plurality of inorganic nanowires onto a surface of the layer of cross-linkable polymer and embedding at least some of the plurality of inorganic nanowires into the layer of cross-linkable polymer to form an inorganic mesh within the layer of cross-linkable polymer, thereby forming the composite conductive film. The method further includes cross-linking the cross-linkable polymer within at least a surface portion of the composite conductive film, wherein following the cross-linking, the cross-linkable polymer within at least the surface portion of the composite conductive film is in a cross-linked state.

A PCBA for use in a high-energy broadband electric field includes a low-voltage power supply and alternating conductive and dielectric layers. An outermost one of the conductive layers includes a dielectric surface switch having closely-spaced switch contacts. The first switch contact is connected to the positive terminal and the second switch contact connected to the negative terminal. Vias connect the conductive layers to the terminals through the respective first and second switch contacts to form power and ground planes. A metamaterial layer of nickel is doped with up to 20 percent phosphorus or chromium by weight, has a uniform thickness of less than 5 m, is sandwiched between interfacing surfaces of a pair of the conductive and dielectric layers, and evenly coats one of the interfacing surfaces. A sonobuoy system includes the PCBA, e.g., an Electronic Function Select board, a cylindrical housing, and an acoustic array.

The present invention relates to a surface-treated copper foil, which has excellent adhesive strength with a resin substrate, shows low bending deformation after adhesion with a resin substrate, and is suitable as a high-frequency foil due to its low transmission loss, to a copper clad laminate comprising same, and to a printed wiring board.

Semiconductor packages including package substrates having non-homogeneous dielectric layers, and methods of fabricating such semiconductor packages, are described. In an example, a semiconductor package substrate includes a dielectric layer having a resin-rich region, e.g., a resin-rich sublayer, and a filler-rich region, e.g., a filler-rich sublayer. The sublayers may contain respective mixtures of an organic resin material and an inorganic filler material. The filler-rich sublayer may have a higher density of the inorganic filler material than the resin-rich sublayer. A density of the inorganic filler material may be lesser near a top surface of 0 the dielectric layer in which an electrical interconnect is embedded. The electrical interconnect may have a greater adhesion affinity to the organic resin material than the inorganic filler material, and thus, the electrical interconnect may readily attach to the functionally-graded dielectric layer.

A method of fabricating a composite conductive film is provided. The method includes providing, as a matrix, a layer of cross-linkable polymer while the cross-linkable polymer is in a substantially noncross-linked state. The method further includes introducing a plurality of inorganic nanowires onto a surface of the layer of cross-linkable polymer and embedding at least some of the plurality of inorganic nanowires into the layer of cross-linkable polymer to form an inorganic mesh within the layer of cross-linkable polymer, thereby forming the composite conductive film. The method further includes cross-linking the cross-linkable polymer within at least a surface portion of the composite conductive film, wherein following the cross-linking, the cross-linkable polymer within at least the surface portion of the composite conductive film is in a cross-linked state.