Abstract:
A substrate has at least one via-in-pad that includes a bond pad and a bore. In addition, the substrate has a plug coupled to the at least one via-in-pad, the plug has a first conductive material and adapted to couple with a solder ball having a second conductive material, the first conductive material having a higher reflow temperature than the second conductive material.
Abstract:
A through hole 2 in a circuit board 1 and to be joined to a lead 5 in a surface mounting component 6 is prepared from a material such as nickel, and palladium having a thermal conductivity equal to or less than 100 W/m.K, the circuit board 1 involving a alloy layer composed of at least a member selected from elements of solder 8, a pad 7, and the lead 5 in a solder joined site of the lead 5 and the pad 7, whereby a quantity of heat transmitted to the joined site via the through hole 2 is reduced at the time when wave-soldering is applied to the back of the circuit board 1 after the surface mounting component 6 was mounted, so that the joined site is maintained at a temperature equal to or less than a melting point of the alloy layer, and hence, exfoliation in an interface of the joined site is prevented, and reliability in the joint of the lead 5 and the pad 7 is elevated.
Abstract:
A soldering system which reduces the numbers of steps for paste supply and soldering onto a printed circuit board. A printed circuit board has through holes through which a lead of each provided part is to be inserted. A printing mask is matched with the through holes and a paste receiving plate having holes to which solder paste is supplied corresponding to the through holes is disposed. A printing roller is swept by forcibly rotating it to fill with solder paste, then a printing squeegee follows the printing roller to further fill through holes. Parts are loaded on the through holes and reflowing is carried out on the printed circuit board and paste receiving plate, so that the parts are soldered to the printed circuit board.
Abstract:
In the formation of through wirings in a silicon substrate and so forth, there was a need for the development of a technology that would allow metal to be reliably filled particularly in the vicinity of openings of through holes and other fine holes. This invention provides a metal filling method and member with filled metal sections in which, in the inflow and filling of a plating solution into through holes 11 of a substrate 10 by immersing said substrate 10 in heated and melted conductive metal, filled metal sections are formed by preliminarily forming a metal layer 15 on the inner surface of one of the ends of through holes 11 of this substrate 10 as well as on substrate top surface 13 around those openings, removing substrate 10 on which inflow and filling of the plating solution into through holes 11 has been completed from the plating solution, and then cooling to solidify the plating solution that has been filled into the through holes.
Abstract:
An inductor for a computer power supply module is provided. The inductor includes a one-piece, single turn winding formed of a material for conducting heat and electrical current. The material having at least about five times the amount of electrically conductive material necessary for conducting electrical current.
Abstract:
Each of junctions formed between a semiconductor device and a substrate comprises metal balls of Cu, or other materials and compounds of Sn and the metal balls, and the metal balls are bonded together by the compounds.
Abstract:
Edge mounting flexible media to a rigid PC board construction can be achieved by various methods. In any method used, there is a desire to create solderable pads on the edge of the rigid PC board. In accordance with the invention, the solderable pads are created by edge plating the PC Board or by a sliced via method. Depending on the type of flexible transmission line used, the construction will differ accordingly. For terminating flexible circuit media, the flex pads are laid out in such a way that the pads are etched in a configuration that matches up with the edge pads on the rigid PC Board. Solder past is then applied to the pads on the flex. The rigid PC Board is fixtured at a right angle to the flex and run through the reflow oven.
Abstract:
A mounting structure of a semiconductor package can improve resistance against thermal and mechanical external force. The mounting structure of a semiconductor package establishes electrical connection of a pad on a printing circuit board to a connection wiring by soldering the semiconductor package. The pad may be integrally formed with a via. The soldering may be performed by penetrating a part of solder within the via so that the connection wiring is connected to the pad through the via at a layer different from a layer of the pad.
Abstract:
Fine pitch area array packaging is achieved using a via-in-pad design within the area array attach portion of a printed circuit board (PCB). The limitation of the design is the wicking action, whereby solder applied to the capture pad contact surface is depleted by capillary action into the via hole when reflowed, causing insufficient solder to be present at the contact surface to effect reliable and repeatable electrical connections. In one implementation, an initial application of solder is applied to plug the via hole with a material having a higher final melting temperature than eutectic solder, thereby providing a stable plug. This plug is formed by the initial solder application that may be either a eutectic solder containing a third metal that forms intermetallic compounds, when reflowed, that elevate the liquidus temperature or a solder having a different formulation with an inherent higher melting temperature. An alternative implementation is to plate the via hole with a material, such as nickel, which prevents eutectic solder, applied to the via capture pad contact surface, from wetting the hole surface and being drawn away from the contact surface by capillary action. Thus, the solder, applied to the via capture pad and used to establish an electrical connection is not depleted.
Abstract:
A ball-grid array connector structure for an electronic package in which the ball pitch can be reduced to increase the packaging density has a plastic substrate having at least one hollow through-hole and an electrode covering the wall of the through-hole and forming an electrode pad surrounding the through-hole on each surface of the substrate. A metallic ball is joined, either directly or through a solder or a combination of a metallic bump and a solder, to the electrode pad on at least one surface of the substrate at the position of the through-hole. The connector structure can be formed either by sealing an open end of the through-hole on the side to which the ball is not joined, or increasing the pressure within the through-hole by a pressure-control mechanism, before the through-hole is blocked by reflowing the ball itself or the metallic bump or solder used to connect the ball.