Abstract:
Solder pads for improving reliability of a semiconductor package are provided. The package includes a substrate and/or a chip. The solder pad includes a plurality of first solder pads located on a surface of the substrate and/or the chip, and at least a second solder pad located on a predetermined region of the surface of the substrate and/or the chip. Each of the first solder pads has a first diameter. The second solder pad has a second diameter greater than the first diameter so as to sustain a stronger thermal stress on the substrate and/or the chip.
Abstract:
A multilayered substrate includes a plurality of connection point groups, each including connection points. At least two inside conductors are each electrically coupled to inside connection points in at least two connection point groups, wherein each of the inside conductors is substantially equal in length between the inside connection points of adjacent connection point groups which is defined as a inside conductor length. At least two outside conductors are each electrically coupled to outside connection points in at least two connection point groups, wherein each of the outside conductors is substantially equal in length between the outside connection points of the adjacent connection point groups which is defined as an outside conductor length. The inside conductor length is shorter than the outside conductor length.
Abstract:
A circuit board comprising a first solder leading land 13a disposed next to a mounting land located rearmost in a direction the circuit board moving during flow soldering of an electronic component, and a second solder leading land 13b disposed behind the first solder leading land 13a against the direction. The present invention provides a circuit board which can effectively prevent solder bridges caused by excessive solder accumulated around leads and lands located in the rearmost position while the electronic component is flow soldered at narrow pitches as is represented by a case with QFPIC. The circuit board of the present invention is suitable for use of lead-free solder, thus contributes to an environment protection.
Abstract:
Patterns for a routable interface of the signal lines of a integrated circuit device include several groups of terminals distributed about the pattern center, each group clustered along a corresponding curvilinear reference segment extending outward from the pattern center to its perimeter. Routability zones are created between each successive pair of groups. For higher terminal density, in at least one of the terminal groups of the pattern, either the offset of the terminals from the reference line segment is not uniform, or the distance of the terminals from the pattern center does not increase uniformly. A portion, preferably at least about 50% of the terminals in a group of the pattern are not collinear with, but offset from, the reference segment. A portion, preferably at least about 90% of the terminals in a given terminal group are each closer to the reference line segment of that terminal group than they are to the reference segment of another terminal group. The patterns of this invention can be employed on IC chips, IC package layers and PCB layers for patterning of terminals, pins, via, pads and another connector devices useful in IC devices.
Abstract:
A printed circuit board apparatus, configurations and methods are presented which provide for close spacing between the HUB and multiple processors as well as a common configuration for two or four processor boards. A printed circuit board is provided with conductive apertures and portions corresponding to an efficient Packaging allowing for the attachment of the processor-chip on one side of the printed circuit board, and the HUB and other supporting electronic components on the other side of the printed circuit board. This configuration allows for the close spacing of the electrical conductors of the HUB and the processors without the limitations imposed by the physical dimensions of the respective hardware. Additionally, a symmetric packaging of the conductive apertures and portions about a centerline of the printed circuit board allows for a simple design modification to allow for a two two-processor board to be manufactured from a similarly configured four-processor board.
Abstract:
A semiconductor device includes a wiring pattern formed on a board, and a semiconductor chip bonded to the wiring pattern by ultrasonic welding. The wiring pattern is formed such that when the semiconductor chip is disposed on the wiring pattern, a range shared between the wiring pattern and positional variation regions of portions to be bonded of the semiconductor chip accompanied by the ultrasonic welding becomes as wide as possible. Such a semiconductor device makes it possible to ensure a sufficient positional deviation range of a wiring pattern with respect to a positional deviation in each bump type electrode, and hence to cope with a multi-pin structure for flip-chip mounting and to improve both an initial bonding characteristic and a mounting reliability.
Abstract:
A circuit board of the invention comprises: an insulating base, which has a semiconductor element mounting portion on an top or bottom side thereof, and on which wiring patterns led out of the semiconductor element mounting portion are installed; and a plurality of substantially circular terminal pads, which are formed on the bottom side of the insulating base, which are connected to the wiring patterns, and to which solder terminals will be joined, wherein each of the terminal pads is provided with a solder lead portion which projects from a center side toward a perimeter side of the insulating base in a diametrical direction of the terminal pad. A part of the solder terminal is pulled out at the solder lead portion, whereby it is possible to prevent a fatigue failure of a joint of the terminal pad and the solder terminal due to a concentration of thermal stress, to electrically connect the solder terminal to the terminal pad in a stable manner for a long time period.
Abstract:
A method for wave soldering comprises the steps of providing a circuit board having a plurality of electronic components thereon and providing a pallet comprising a frame, first and second parallel rails attached to the frame, and third and fourth rails for receiving the circuit board. The third and fourth rails are attached to the first and second rails and the third and fourth rails form an angle of between about 30.degree. and 60.degree. with the first and second rails. Next, a solder wave is provided which generally flows in a first direction. Finally, the pallet is moved in a second direction generally perpendicular with the first direction across the solder wave. The components are therefore positioned at an angle with respect to the solder wave and solder-related electrical defects are reduced.
Abstract:
In order to produce keyboards, two pairs of diagonally connected squares with rounded corners are used as fixed contacts. A direct diagonal connection electrically connects two non-adjacent squares. The squares are conductive lacquer (carbon lacquer) and cover copper pads on a printed circuit board.
Abstract:
A pallet for holding a printed circuit board comprises first and second parallel rails and third and fourth parallel rails. The third and fourth rails each have first and second ends and form an angle of between about 30.degree. and 60.degree. with the first and second rails. The first and second ends of the third and fourth rails are connected to one of the first and second rails. The pallet further comprises an attachment for securing the printed circuit board to the third and fourth rails. The angled pallet has advantages over conventional pallets as shorts and shadowing are reduced.