The present invention relates to a method for producing a metal wire embedded flexible substrate from a laminate structure. The laminate structure includes a carrier substrate, a debonding layer disposed on at least one surface of the carrier substrate and including a polyimide resin, a metal wiring layer disposed in contact with the debonding layer, and a flexible substrate layer disposed in contact with the metal wiring layer. The adhesion strength between the metal wiring layer and the flexible substrate layer is greater than that between the metal wiring layer and the debonding layer. According to the method of the present invention, the flexible substrate with the metal wiring layer can be easily separated from the carrier substrate even without the need for other processes, such as laser and light irradiation. The embedding of the metal wires in the flexible substrate layer decreases the sheet resistance of an electrode and can protect the metal wires from damage or disconnection even when the flexible substrate is deformed in shape.

The present invention relates to a method for producing a metal wire embedded flexible substrate from a laminate structure. The laminate structure includes a carrier substrate, a debonding layer disposed on at least one surface of the carrier substrate and including a polyimide resin, a metal wiring layer disposed in contact with the debonding layer, and a flexible substrate layer disposed in contact with the metal wiring layer. The adhesion strength between the metal wiring layer and the flexible substrate layer is greater than that between the metal wiring layer and the debonding layer. According to the method of the present invention, the flexible substrate with the metal wiring layer can be easily separated from the carrier substrate even without the need for other processes, such as laser and light irradiation. The embedding of the metal wires in the flexible substrate layer decreases the sheet resistance of an electrode and can protect the metal wires from damage or disconnection even when the flexible substrate is deformed in shape.

A fabric-based item may include fabric layers and other layers of material. An array of electrical components may be mounted in the fabric-based item. The electrical components may be mounted to a support structure such as a flexible printed circuit. The flexible printed circuit may have a mesh shape formed from an array of openings. Serpentine flexible printed circuit segments may extend between the openings. The electrical components may be light-emitting diodes or other electrical devices. Polymer with light-scattering particles or other materials may cover the electrical components. The flexible printed circuit may be laminated between fabric layers or other layers of material in the fabric-based item.

A method for manufacturing a ceramic substrate containing glass includes a firing step in which an unfired silver-based conductor material is disposed on an unfired ceramic layer and is fired. The unfired silver-based conductor material contains at least one of a metal boride and a metal silicide.

[Problem] To achieve a wiring board capable of suppressing the difference in the amount of delay between two signal wirings constituting differential signal wirings, while securing flexibility in design.

[Solution] A wiring board is configured to include a first insulating layer 1, a first signal wiring 2 and a second signal wiring 3. The first insulating layer 1 includes fibers 4 having the long axis in a first direction and aligned approximately parallel to each other at a first interval and an insulating material 5 filling gaps between the fibers 4 of the first direction. The first signal wiring 2 is formed approximately parallel to the first direction on the first insulating layer 1. The second signal wiring 3 is formed parallel to the first signal wiring 2 such that the interval between the first and second signal wirings 2 and 3 be approximately an integral multiple of the first interval, and the second signal wiring 3 transmits a differential signal of a signal transmitted on the first signal wiring 2.

A glass substrate for a high-frequency device, which contains SiO.sub.2 as a main component, the glass substrate having a total content of alkali metal oxides in the range of 0.001-5% in terms of mole percent on the basis of oxides, the alkali metal oxides having a molar ratio represented by Na.sub.2O/(Na.sub.2O+K.sub.2O) in the range of 0.01-0.99, and the glass substrate having a total content of alkaline earth metal oxides in the range of 0.1-13% in terms of mole percent on the basis of oxides, wherein at least one main surface of the glass substrate has a surface roughness of 1.5 nm or less in terms of arithmetic average roughness Ra, and the glass substrate has a dielectric dissipation factor at 35 GHz of 0.007 or less.

A glass substrate for a high-frequency device, which contains SiO.sub.2 as a main component, the glass substrate having a total content of alkali metal oxides in the range of 0.001-5% in terms of mole percent on the basis of oxides, the alkali metal oxides having a molar ratio represented by Na.sub.2O/(Na.sub.2O+K.sub.2O) in the range of 0.01-0.99, and the glass substrate having a total content of alkaline earth metal oxides in the range of 0.1-13% in terms of mole percent on the basis of oxides, wherein at least one main surface of the glass substrate has a surface roughness of 1.5 nm or less in terms of arithmetic average roughness Ra, and the glass substrate has a dielectric dissipation factor at 35 GHz of 0.007 or less.

The present invention provides a resin composition comprising a cyanate compound (A); and an epoxy resin (B) represented by general formula (1):

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wherein a plurality of R each independently represent any of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and an alkoxy group having 1 to 6 carbon atoms.

An embedded power module includes a substrate, first and second semiconducting dies, first and second gates, and first and second vias. The first semiconducting die is embedded in the substrate and spaced between opposite first and second surfaces of the substrate. The second semiconducting die is embedded in the substrate, is spaced between the first and second surfaces, and is spaced from the first semiconducting die. The first gate is located on the first surface. The second gate is located on the second surface. The first via is electrically engaged to the first gate and the second semiconducting die, and the second via is electrically engaged to the second gate and the first semiconducting die.

A circuit board element includes a glass substrate, a first dielectric layer, and a first patterned metal layer. The glass substrate has an edge. The first dielectric layer is disposed on the glass substrate and has a central region and an edge region. The edge region is in contact with the edge of the glass substrate, and the thickness of the central region is greater than the thickness of the edge region. The first patterned metal layer is disposed on the glass substrate and in the central region of the first dielectric layer.