A ceramic circuit substrate is suitable for silver nanoparticle bonding of semiconductor elements and has excellent close adhesiveness with a power module sealing resin. A ceramic circuit substrate has a copper plate bonded, by a braze material, to both main surfaces of a ceramic substrate including aluminum nitride or silicon nitride, the copper plate of at least one of the main surfaces being subjected to silver plating, wherein: the copper plate side surfaces are not subjected to silver plating; the thickness of the silver plating is 0.1 m to 1.5 m; and the arithmetic mean roughness Ra of the surface roughness of the circuit substrate after silver plating is 0.1 m to 1.5 m.

An evacuated core circuit board (10) for dissipating heat from a heat generating electronic component, the evacuated core circuit board comprising: at least one circuit layer (12) to which the heat generating electronic component (14) is electronically coupled; a base layer (16) a comprising a body structure (19) having a substantially hollow interior (20); and a dielectric layer (18) provided between at least a portion of the circuit layer (12) and the base layer (16), wherein the hollow interior (20) is at least partially evacuated.

Disclosed are: a microetching agent which can form roughened shapes less affected by differences in the crystallinity of the copper and with which roughened shape excellent in terms of adhesiveness to resins, etc. can be formed on either electrolytic copper or rolled copper; and a method for producing a wiring board which includes a step of roughening a copper surface using the microetching agent. In the present invention, the microetching agent for copper is an acidic aqueous solution containing an inorganic acid, a cupric ion source, a halide ion source, and a polymer. The polymer has a functional group containing a nitrogen atom. It is preferable that the microetching agent contain a sulfate ion source.

The present invention relates to a metallic nano structure including a plurality of metallic nano materials; and a junction locally disposed in a region where the metallic nano materials adjacent to each other among the plurality of metallic nano materials are in contact with each other in order to bond the adjacent metallic nano materials.

Electrodeposited copper foils having properties suitable for use as current collectors in lithium-ion secondary batteries are disclosed. The electrodeposited copper foils include a drum side and a deposited side. At least one of the deposited side or the drum side exhibits a void volume (Vv) value in the range of 0.17 to 1.17 m.sup.3/m.sup.2.

Electrodeposited copper foils having properties suitable for use as negative electrode current collectors in lithium-ion secondary batteries are disclosed. The copper foil has a yield strength in the range of 11 to 45 kg/mm.sup.2, and a difference in residual stress between the drum side and the deposited side of at most 95 MPa. Negative electrode current collectors for lithium-ion secondary battery, a lithium-ion secondary battery incorporating the negative electrode, and batteries containing the negative electrode current collector are also disclosed.

A surface-treated copper foil of the present disclosure includes a copper foil substrate, at least one surface of which has a surface treatment coat including at least a roughening-treated surface on which roughening particles are formed. Observation of a cross-section of the surface-treated copper foil with a scanning electron microscope shows that on a surface of the surface treatment coat, a standard deviation of the particle height of the roughening particles is 0.16 m or more and 0.30 m or less, and an average value of the ratio of the particle height to the particle width (particle height/particle width) of the roughening particles is 2.30 or more and 4.00 or less.

A surface-treated copper foil according to exemplary embodiments includes a copper foil layer and a protrusion layer formed on one surface of the copper foil layer. Pores are formed inside the protrusion layer or around a boundary between the copper foil layer and the protrusion layer. Abnormal growth of the protrusions may be prevented through the pores and thus a bonding force with the insulation layer may be improved.

The present disclosure generally relates to printed circuit boards or printed circuit board assemblies for fiber optic communications. In one example, a method may include coupling at least one optoelectronic component to a surface of a printed circuit board. The method may include lasering the surface of the printed circuit board to form a laser-roughened area on the surface of the printed circuit board. The method may include coupling an optical component to the printed circuit board at the laser-roughened area on the surface of the printed circuit board.

A copper foil for printed circuits is prepared by forming a primary particle layer of copper on a surface of a copper foil, and then forming a secondary particle layer based on ternary alloy composed of copper, cobalt and nickel on the primary particle layer. The average particle size of the primary particle layer is 0.25 to 0.45 m, and the average particle size of the secondary particles layer based on ternary alloy composed of copper, cobalt and nickel is 0.05 to 0.25 m. Provided is a copper foil for printed circuits, in which powder fall from the copper foil can be reduced and the peeling strength and heat resistance can be improved by forming a primary particle layer of copper on a surface of a copper foil, and then forming a secondary particle layer based on copper-cobalt-nickel alloy plating on the primary particle layer.