A system of circuit card components each include through-holes for soldering having recessed copper layers for thermal insulation. Thermal insulation prevents heat conduction away from flowing solder, allowing the solder to flow freely through the through-hole. Even high-temperature, lead-free solders may maintain the necessary temperature to flow. Different circuit layers include specialized features based on distance from a top or bottom surface. Vias surrounding the through-hole maintain the necessary cross-sectional area for electrical connectivity.

A multilayer printed circuit board includes a plurality of conductive layers formed by a conductive material, in which a blank region with the conductive material removed is formed in at least part of at least an intermediate conductive layer that is formed inside the multilayer printed circuit board, among the plurality of conductive layers, a plurality of island regions are formed by the conductive material included in the intermediate conductive layer in the blank region, and each of the plurality of island regions is not electrically connected to other regions included in the intermediate conductive layer and is disposed so as to be dispersed from one another.

A method of a circuit signal enhancement of a circuit board comprises the following steps: forming a first substrate body with a first signal transmission circuit layer and a second substrate body with a second signal transmission circuit layer; forming a first signal enhancement circuit layer and a second signal enhancement circuit layer on the first substrate body and the second substrate body; forming a third substrate body with a third signal transmission circuit layer and a fourth substrate body with a fourth signal transmission circuit layer on the carrier; separating the third substrate body and the fourth substrate body from the carrier; combining the first signal transmission circuit layer and the third signal transmission circuit layer through the first signal enhancement circuit layer; and combining the second signal transmission circuit layer and the fourth signal transmission circuit layer through the second signal enhancement circuit layer.

The present invention provides a method for detecting and adjusting failed back-drills in PCBs in the process of fabricating a PCB so that the failed back-drill can be screened out or repaired. This is accomplished, by after detecting poor back drills in a PCB, measuring the actual thickness of each PCB board. Next, the measured actual thickness of each PCB board is compared with .the theoretical thickness of each PCB board. The back drill depth for each area of the PCB board is then adjusted for its theoretical thickness and percent variation from the measured thickness.to adjust the poor back drill.

A method for manufacturing a circuit board structure with a waveguide is provided. The method includes: providing a first substrate unit, a second substrate unit, a third substrate unit, and two adhesive layers, the first substrate unit including a first dielectric layer and a first conductive layer, the first conductive layer including a first shielding area and two first artificial magnetic conductor areas disposed on two sides of the first shielding area; the second substrate unit including a second dielectric layer and a second conductive layer, the second conductive layer including a second shielding area; the third substrate unit defining a first slot, and the adhesive layer defining a second slot; stacking the first substrate unit, one of the adhesive layers, the third substrate unit, another one of the adhesive layers, and the second substrate unit in that order; pressing the intermediate body.

An electromagnetic wave transmission board proofed against internal signal leakage includes an inner plate, a first outer plate, a second outer plate, a first plate bump, a first conductive bump, a second plate bump, and a second conductive bump. The inner plate defines a first through hole with a plated metal layer on the hole wall. The first and second plated bumps are disposed between the first outer and inner plates. The second plate bump and the second conductive bump are disposed between the second outer plate and the inner plate. The plate metal layer, the first plate bump, the first conductive bump, the first outer plate, the second outer plate, the second conductive bump, and the second plated bump jointly form an air-filled chamber. A method for manufacturing the electromagnetic wave transmission board is also provided.

A method for step-soldering includes applying a first solder alloy having a melting point in a temperature range from 160 to 210° C. to a jointed portion of a first electronic component and a substrate, and heating them in the temperature range from 160 to 210° C., and applying a second solder alloy having the melting point in a temperature range lower than 160° C. to a joint portion of a second electronic component and the substrate, and heating them in the temperature range lower than 160° C. The first solder alloy consists of 13-22 mass % of In, 0.5-2.8 mass % of Ag, 0.5-5.0 mass % of Bi, 0.002-0.05 mass % of Ni and a balance Sn.

A lighting strip has a printed circuit board with one or more perforated lines at which the printed circuit board length may be adjusted by breaking off an end portion of the printed circuit board. A first layer has a first set of conductive tracks and a second layer has a second set of conductive tracks corresponding to the first set of conductive tracks. Each conductive track of the second set is vertically aligned and positioned over the corresponding conductive track of the first set. An array of contact terminals is provided on a third layer. A plurality of lighting elements is disposed along the lighting strip, each electrically connected to a respective pair of the contact terminals. The lighting strip further comprises a set of vias connecting each conductive track of the first set to the corresponding conductive track of the second set.

According to one embodiment, a semiconductor memory system includes a substrate, a plurality of elements and an adhesive portion. The substrate has a multilayer structure in which wiring patterns are formed, and has a substantially rectangle shape in a planar view. The elements are provided and arranged along the long-side direction of a surface layer side of the substrate. The adhesive portion is filled in a gap between the elements and in a gap between the elements and the substrate, where surfaces of the elements are exposed.

A circuit board includes at least one circuit board unit sequentially stacked in a thickness direction of the circuit board, an insulating layer, an electromagnetic shielding layer, and a barrier layer. The circuit board unit includes a substrate layer, and two conductive layers respectively disposed on two opposite sides of the substrate layer in a thickness direction of the substrate layer, and each of the conductive layers includes a plurality of signal lines. The insulating layer is located on a side of an outermost conductive layer away from the substrate layer. The electromagnetic shielding layer is located on a side of the insulating layer away from the substrate layer. The barrier layer is located between the electromagnetic shielding layer and the outermost conductive layer. The barrier layer at least covers a plurality of signal lines in the outermost conductive layer.