Abstract: Where an electrical connection is needed between an electric circuit on a substrate and a component with very finely spaced leads, pads are formed on the substrate at points where such connections to the circuit are to be made. A solder paste is deposited using a particular, described stencil having a thickness and apertures with specific tolerances. The component is positioned so that its leads to be attached are contiguous with corresponding pads, and the electrical connections are completed by reflowing the solder paste forming consistent and reliable electrical joints of solder alloy.

Abstract: A method and apparatus for efficiently repairing or reworking a printed circuit board having a solder ball grid array thereon efficiently and at minimum cost includes the steps of drilling out a plated-through hole to sever electrical connections between a ball grid array pad on one surface of the printed circuit board and internal circuits and circuits on an opposite surface of the printed circuit board; inserting a pin having an insulated sleeve surrounding a portion thereof into the drilled-out hole, the pin having attached to one end a wire for attachment to the ball grid array on one surface of the printed circuit board and a post at the other end of the pin for attachment of a wire to the post; the pin having a stop along its length to control vertical positioning of the pin in the drilled-out hole, the pin referred to as a via replacement (VR) pin.

Abstract: A method and apparatus for efficiently repairing or reworking a printed circuit board having a solder ball grid array thereon efficiently and at minimum cost includes the steps of drilling out a plated-through hole to sever electrical connections between a ball grid array pad on one surface of the printed circuit board and internal circuits and circuits on an opposite surface of the printed circuit board; inserting a pin having an insulated sleeve surrounding a portion thereof into the drilled-out hole, the pin having attached to one end a wire for attachment to the ball grid array on one surface of the printed circuit board and a post at the other end of the pin for attachment of a wire to the post; the pin having a stop along its length to control vertical positioning of the pin in the drilled-out hole, the pin referred to as a via replacement (VR) pin.

Abstract: A method and apparatus for efficiently repairing or reworking a printed circuit board having a solder ball grid array thereon efficiently and at minimum cost includes the steps of drilling out a plated-through hole to sever electrical connections between a ball grid array pad on one surface of the printed circuit board and internal circuits and circuits on an opposite surface of the printed circuit board; inserting a pin having an insulated sleeve surrounding a portion thereof into the drilled-out hole, the pin having attached to one end a wire for attachment to the ball grid array on one surface of the printed circuit board and a post at the other end of the pin for attachment of a wire to the post; the pin having a stop along its length to control vertical positioning of the pin in the drilled-out hole, the pin referred to as a via replacement (VR) pin.

Abstract: A high strength ternary lead-free solder alloy, solder paste and method. The alloy consists essentially of a major portion of tin, from in excess of 5 wt % bismuth to 25 wt % bismuth and 2 to 5 wt % silver.

Abstract: Where an electrical connection is needed between an electric circuit on a substrate and a component with very finely spaced leads, pads are formed on the substrate at points where such connections to the circuit are to be made. A solder paste is deposited using a particular, described stencil having a thickness and apertures with specific tolerances. The component is positioned so that its leads to be attached are contiguous with corresponding pads, and the electrical connections are completed by reflowing the solder paste forming consistent and reliable electrical joints of solder alloy.

Abstract: A method and apparatus for efficiently repairing or reworking a printed circuit board having a solder ball grid array thereon efficiently and at minimum cost includes the steps of drilling out a plated-through hole to sever electrical connections between a ball grid array pad on one surface of the printed circuit board and internal circuits and circuits on an opposite surface of the printed circuit board; inserting a pin having an insulated sleeve surrounding a portion thereof into the drilled-out hole, the pin having attached to one end a wire for attachment to the ball grid array on one surface of the printed circuit board and a post at the other end of the pin for attachment of a wire to the post; the pin having a stop along its length to control vertical positioning of the pin in the drilled-out hole, the pin referred to as a via replacement (VR) pin.

Abstract: A method and apparatus for efficiently repairing or reworking a printed circuit board having a solder ball grid array thereon efficiently and at minimum cost includes the steps of drilling out a plated-through hole to sever electrical connections between a ball grid array pad on one surface of the printed circuit board and internal circuits and circuits on an opposite surface of the printed circuit board; inserting a pin having an insulated sleeve surrounding a portion thereof into the drilled-out hole, the pin having attached to one end a wire for attachment to the ball grid array on one surface of the printed circuit board and a post at the other end of the pin for attachment of a wire to the post; the pin having a stop along its length to control vertical positioning of the pin in the drilled-out hole, the pin referred to as a via replacement (VR) pin.

Abstract: A high solidus temperature, high service temperature, high strength ternary solder alloy, solder paste and method. The alloy contains a major proportion of tin of at least about 70% by weight, a selectively limited amount of silver from about 6.5 to about 7.5% by weight, balance indium.

Abstract: A high solidus temperature, high service temperature, high strength ternary solder alloy, solder paste and method. The alloy contains a major proportion of tin of at least about 70% by weight, a selectively limited amount of silver from about 6.5 to about 7.5% by weight, balance indium.

Abstract: A method and apparatus for efficiently repairing or reworking a printed circuit board having a solder ball grid array thereon efficiently and at minimum cost includes the steps of drilling out a plated-through hole to sever electrical connections between a ball grid array pad on one surface of the printed circuit board and internal circuits and circuits on an opposite surface of the printed circuit board; inserting a pin having an insulated sleeve surrounding a portion thereof into the drilled-out hole, the pin having attached to one end a wire for attachment to the ball grid array on one surface of the printed circuit board and a post at the other end of the pin for attachment of a wire to the post; the pin having a stop along its length to control vertical positioning of the pin in the drilled-out hole, the pin referred to as a via replacement (VR) pin.

Abstract: Where an electrical connection is needed between an electric circuit on a substrate and a component with very finely spaced leads, pads are formed on the substrate at points where such connections to the circuit are to be made. A solder paste is deposited using a particular, described stencil having a thickness and apertures with specific tolerances. The component is positioned so that its leads to be attached are contiguous with corresponding pads, and the electrical connections are completed by reflowing the solder paste forming consistent and reliable electrical joints of solder alloy.

Abstract: The method for soldering a chip to a substrate to form a module and then soldering the module to a circuit board includes selecting a three level hierarchy of solders by the temperature required to melt. By this method, a module can be soldered to and de-soldered from a circuit board without affecting adversely the solder between the chip and the substrate. The package formed by this method is free of faults that are caused frequently during both manufacture and service.

Abstract: The method for soldering a chip to a substrate to form a module and then soldering the module to a circuit board includes selecting a three level hierarchy of solders by the temperature required to melt. By this method, a module can be soldered to and de-soldered from a circuit board without affecting adversely the solder between the chip and the substrate. The package formed by this method is free of faults that are caused frequently during both manufacture and service.