A circuit board according to an embodiment includes a first insulating portion including at least one insulating layer; a second insulating portion disposed on the first insulating portion and including at least one insulating layer; and a third insulating portion disposed under the first insulating portion and including at least one insulating layer; wherein the insulating layer constituting the first insulating portion includes a prepreg containing glass fibers, and wherein each of the insulating layers constituting the second and third insulating portions is made of resin coated copper (RCC).

A method of fabricating a composite conductive film is provided. The method includes providing, as a matrix, a layer of cross-linkable polymer, where the cross-linkable polymer is in a non-cross-linked state. The method further includes introducing inorganic nanowires upon a surface of the layer of cross-linkable polymer. The inorganic nanowires are, in isolated form, characterized by a first conductivity stability temperature. The method further includes embedding at least some of the inorganic nanowires into the layer of cross-linkable polymer to form an inorganic mesh, thereby forming the composite conductive film. The method further includes cross-linking the polymer within a surface portion of the composite conductive film. Cross-linking the polymer within the surface portion of the composite conductive film results in the surface portion having a second conductivity stability temperature that is greater than the first conductivity stability temperature.

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 wirings and electro-conductive contact sheet group both laid on the surface of the substrate, where the substrate is overlaid with solder resist, and the solder resist has no contact with the electro-conductive contact sheet group.

A stretchable wire assembly includes a metal wire coupled between two elastic substrates. The two elastic substrates are selectively coupled together, and the metal wire is attached to one or both elastic substrates at select locations. The form of the metal wire is such that when the elastic substrates are in a relaxed, or non-stretched, state the metal wire forms a tortuous path, such as a waveform, along the coupled elastic substrates. The tortuous path of the metal wire provides slack such that as the elastic substrates are stretched the slack is taken up. Once released, the elastic substrates move from the stretched position to the relaxed, non-stretched position, and slack is reintroduced into the metal wire in the form of the original tortuous path.

A composite conductive film is provided that includes a layer of cross-linked polymer having a surface and an inorganic mesh comprising a plurality of nanowires of an inorganic material. The nanowires are, in isolated form, characterized by a first conductivity stability temperature. Further, the plurality of nanowires is embedded within at least a region of the layer of cross-linked polymer, where the region is continuous from the surface of the layer of cross-linked polymer. The layer of cross-linked polymer and the inorganic mesh are arranged to form the composite conductive film having a second conductivity stability temperature that is greater than the first conductivity stability temperature.

A layer stack for a touch panel is described. The layer stack includes a substrate including a polymer for depositing one or more layers on the substrate; a patterned transparent conductive oxide (TCO) layer provided over the substrate, which comprises areas of TCO and gaps between the areas of TCO; a first dielectric material provided in the gaps of the patterned TCO layer and a dielectric layer being deposited directly on the TCO areas of the TCO layer and directly on the first dielectric material. Further, a touch panel including a layer stack and a method for forming a layer stack for a touch panel is described.

Low dielectric constant (low-k) polyhemiaminal (PHA) and polyhexahydrotriazine (PHT) materials with cyclic aliphatic ring structures are described. The materials are formed by a method that includes heating a mixture comprising amines and paraformaldehyde. The reaction mixtures may be used to form low-k PHT prepregs, composites and dielectrics used in integrated circuits.

Low dielectric constant (low-k) polyhemiaminal (PHA) and polyhexahydrotriazine (PHT) materials with cyclic aliphatic ring structures are described. The materials are formed by a method that includes heating a mixture comprising amines and paraformaldehyde. The reaction mixtures may be used to form low-k PHT prepregs, composites and dielectrics used in integrated circuits.

A contactless current sensing circuit for sensing current in a conductive wire on a dielectric substrate of a printed circuit board (PCB) includes a plurality of magnetic tunneling junction (MTJ) structures including first and second MTJ structures on a first side of the conductive wire, and third and fourth MTJ structures on a second side of the conductive wire opposite to the first side. The MTJ structures are located within the H-field induced by a current flowing through the conductive wire.

The present disclosure provides a hydrophobic low-dielectric-constant film and a preparation method therefor. The low-dielectric-constant film is formed from one or more fluorine-containing compounds A by means of a plasma enhanced chemical vapor deposition method, and the one or more fluorine-containing compounds comprise a compound having the general formula C.sub.xSi.sub.yO.sub.mH.sub.nF.sub.2x+2yn+2 or C.sub.xSi.sub.yO.sub.mH.sub.nF.sub.2x+2yn, x being an integer from 1 to 20, y being an integer from 0 to 8, m being an integer from 0 to 6, and n being 0, 3, 6, 7, 9, 10, 12, 13, 15, 16, 17 and 19. Thus, a nano-film having a low dielectric constant and good hydrophobicity is formed on the surface of a substrate.