A multilayer ceramic substrate according to the present disclosure has ceramic layers and a patterned conductor, and a cavity is formed in the multilayer ceramic substrate. The cavity reaches to any one of principal surfaces of the multilayer ceramic substrate and forms an opening, and the opening is covered with a sealing member at the principal surface of the multilayer ceramic substrate.

In a printed circuit board (1), thermal vias (19) are formed between the lower surface (A) and an upper surface (B) of the substrate plate (10) of the printed circuit board through the steps of: applying a respective solder resist mask (21, 31) to the lower surface (A) and the upper surface (B); applying solder to the lower surface (A) and reflow soldering the solder, wherein the solder penetrates into the boreholes (20) and forms convex menisci (26) protruding beyond the edge (22) of the respective boreholes on the lower surface (A); and creating regions (35) on the upper surface (B), which are freed from solder resist material, and which are intended for contacting at least one electronic component (17) on the upper surface and each of which comprise at least one of the thermal vias. Subsequently, the upper surface (B) can be provided with electrical components (17) on these regions (35). The first solder resist mask (21) has a respective region (23) that is free of solder resist on the lower surface around the edge of every borehole (20).

Systems and methods for providing a soldered interface between a circuit board and a connector pin. The methods comprise: using a jet paste dispenser to apply first solder into a plated contact cavity formed in the circuit board; using a stencil screen printer to apply second solder (a) over the plated contact cavity which was at least partially filled with the first solder by the jet paste dispenser and (b) over at least a portion of a pad surrounding the plated contact cavity; inserting the connector pin in the plated contact cavity such that the connector pin passes through the second solder and extends at least partially through the first solder; and performing a reflow process to heat the first and second solder so as to create a solder joint between the circuit board and the connector pin.

Filing a plated through-hole of a circuit board with solder is facilitated by an apparatus which includes a wire solder assembly and a controller. The wire solder assembly includes a wire probe sized to extend into the plated through-hole from one side of the circuit board, and a solder block associated with the wire probe so that the probe passes through the solder block. The controller controls heating of the wire probe, when the wire probe is operatively inserted into the plated through-hole, by passing a current through the wire probe. The heating of the wire probe heats a conductive plating of the plated through-hole and melts the solder block. The heating of the conductive plating and the melting of the solder block causes the solder to migrate into the plated through-hole by capillary action to fill the plated through-hole with the solder.

A process of fabricating a circuit includes providing a first sheet of dielectric material including a first top surface having at least one first conductive trace and a second sheet of dielectric material including a second top surface having at least one second conductive trace, depositing a first solder bump on the at least one first conductive trace, applying the second sheet of dielectric material to the first sheet of dielectric material with bonding film sandwiched in between, bonding the first and second sheets of dielectric material to one another, and providing a conductive material to connect the first solder bump on the at least one first conductive trace to the at least one second conductive trace.

Electronic assembly methods and structures are described. In an embodiment, an electronic assembly method includes bringing together an electronic component and a routing substrate, and directing a large area photonic soldering light pulse toward the electronic component to bond the electronic component to the routing substrate.

Discovered is a daughter circuit board for direct connection to another mother circuit board. The daughter circuit board has an edge electrode for conductive connection to a surface pad on the mother board. An opening in the daughter circuit board can be aligned with the surface pad on the mother circuit board. The opening can contain solder which when reflowed can establish a bond between the daughter circuit board and the surface pad on the mother circuit board.

Provided is an electronic component mounting structure and method for mounting electronic components on the side of a printed circuit board by means of simple fabrication and enlarging the surface area for mounting electronic components. A cut face of a conductive plating layer, which is obtained by cutting along a via in which a conductive plating layer covering an inner wall face of a via hole is electrically connected to a conductive pattern layer of the printed circuit board, is exposed at a cut end face and used as a land pattern which is solder-connected to a mount connecting portion of the electronic component. The end face at which the land pattern is exposed is a surface parallel to the side of the printed circuit board, and therefore electronic components can be mounted on the end face parallel to the side.

A method of manufacturing a circuit substrate includes forming, in an insulating substrate and circuit patterns that are provided on a first surface and a second surface of the insulating substrate, a through-hole penetrating the insulating substrate and the circuit patterns, where the circuit patterns contain Cu as a main component. The method includes filling, in the through-hole, an electrically conductive paste that is a melting-point shift electrically conductive paste including SnBi solder powder, Cu powder, and resin, and forming a protrusion obtained by causing the electrically conductive paste to protrude from the through-hole. The method further includes performing pressure treatment on the protrusion near the through-hole; and performing heat treatment on the insulating substrate whose protrusion is subjected to the pressure treatment and causing the circuit patterns and the electrically conductive paste to be electrically connected with each other.

Electronic assembly methods and structures are described. In an embodiment, an electronic assembly method includes bringing together an electronic component and a routing substrate, and directing a large area photonic soldering light pulse toward the electronic component to bond the electronic component to the routing substrate.