Embodiments described herein may be related to apparatuses, processes, and techniques directed to bridges having a glass core, where the bridges may include one or more thick traces and one or more thin traces, where the thin traces are layered closer to a surface of the glass core, and the thick traces are layered further away from the glass core. During operation, the thin traces may be used to transmit signals between the coupled dies, and the thick traces may be used to transmit power between the coupled dies. During manufacture, the rigidity and highly planner surface of the glass core may enable thinner traces closer to the surface of the glass core to be placed with greater precision resulting in increased overall quality and robustness of transmitted signals. Other embodiments may be described and/or claimed.

A circuit layer is formed by drilling vias and forming channels in a circuit layer which has catalytic particles exposed on the surfaces, channels, and vias. A first flash electroless deposition is followed by application of dry film, followed by selective laser ablation of the dry film channels and vias. A second electroless solution is applied which provides additional deposition over the first flash electroless deposition but only on the vias and trace channel areas. An electrodeposition follows, using the first deposition as a cathode. The dry film is stripped and the first electroless layer is etched, leaving only depositions in the channels and vias.

A multilayer circuit board structure includes superconducting connections to internal layers thereof, for example by inclusion of superconducting vias. Two or more panels can each comprise respective electrically insulative substrates, each have one or more through-holes, and also include a respective bimetal foil on at least a portion of a respective surface thereof, which is patterned to form traces. The bimetal foil includes a first metal that is non-superconductive in a first temperature range and a second metal that is superconductive in the first temperature range. The panels are plated to deposit a third metal on exposed traces of the second metal, the third metal superconductive in the first temperature range. Panels are join (e.g., laminated) to form at least a three-layer superconducting printed circuit board with an inner layer, two outer layers, and superconducting vias between the inner layer and at least one of the two outer layers.

Embodiments provide a multilayer printed circuit board intended to connect electronic components, the board comprising a stack of a plurality of conductive layers, the conductive layers comprising two surface layers and one or more internal layers, the board comprising one or more counterbored holes, each counterbored hole comprising a portion with metallization opening onto one of the two surface layers and a portion without metallization opening onto the other surface layer; the multilayer printed circuit board may advantageously comprise one or more metal pads, each metal pad being joined to one of the two surface layers so as to occult the portion without metallization of a corresponding counterbored hole.

Embodiments provide a multilayer printed circuit board intended to connect electronic components, the board comprising a stack of a plurality of conductive layers, the conductive layers comprising two surface layers and one or more internal layers, the board comprising one or more counterbored holes, each counterbored hole comprising a portion with metallization opening onto one of the two surface layers and a portion without metallization opening onto the other surface layer; the multilayer printed circuit board may advantageously comprise one or more metal pads, each metal pad being joined to one of the two surface layers so as to occult the portion without metallization of a corresponding counterbored hole.

A method for manufacturing a printed wiring board includes forming through holes in a double-sided copper-clad laminated plate such that a high-density region of the through holes and a low-density region of the through holes are formed, forming an electrolytic plating film on a copper foil of the plate in the high-density and low-density regions, forming a masking resist to mask the plating film in the high-density region, etching the plating film in the low-density region exposed from the resist such that the plating film in the low-density region is thinned, peeling off the resist from the plating film in the high-density region, and forming a conductor circuit including the copper foil and the plating film in the high-density and low-density regions. The forming of the plating film on the copper foil of the plate includes forming the plating film in the through holes in the high-density and low-density regions.

A method for manufacturing a circuit board embeds a portion of an outer circuit layer in an outer dielectric layer which increases contact area between the outer circuit layer and the outer dielectric layer, improving adhesion between the outer circuit layer and the outer dielectric layer, and reducing a thickness of the outer circuit substrate, thereby reducing the overall thickness of the finished circuit board.

A reel-to-reel method to laser-ablate a circuitry pattern on the fly in a reel-to-reel machine as part of a process to fabricate a printed flexible circuit. The laser ablation method includes using an appropriate laser to irradiate a metal sheet thus ablating the edges of an intended circuitry pattern. Slugs can be removed by using an optional sacrificial liner, and the slugs can be optionally ablated into smaller parts first. The laser ablation can also include an optional method of creating tie bars to provide structural support to the web of circuitry patterns.

A reel-to-reel method to laser-ablate a circuitry pattern on the fly in a reel-to-reel machine as part of a process to fabricate a printed flexible circuit. The laser ablation method includes using an appropriate laser to irradiate a metal sheet thus ablating the edges of an intended circuitry pattern. Slugs can be removed by using an optional sacrificial liner, and the slugs can be optionally ablated into smaller parts first. The laser ablation can also include an optional method of creating tie bars to provide structural support to the web of circuitry patterns.

Provided is a liquid mixture for filling blind holes in copper foil, relating to the technical field of electroplating hole filling. The liquid mixture comprises copper sulfate pentahydrate 210-240 g/L, citric acid 40-50 g/L, tartaric acid 10-20 g/L, chloride ion 40-70 ppm, accelerator 0.5-2 g/L, leveling agent 5-15 g/L, inhibitor 5-10 g/L, and sulfonate ion liquid 50-180 g/L. The leveling agent comprises tetranitro blue tetrazolium blue and triazolyl acetyl hydrazide.