Delphi Technologies, Inc.

Delco Electronics Corporation

Shing Yeh

Bradley H Carter

Scott David Brandenburg

William David Higdon

Frank Stepniak

Curtis Wayne Melcher

Mark Wendell Gose

Thomas Alan Degenkolb

Douglas Ray Sparks

Larry Lee Jordan

Ralph Edward Cornell

David A King

William S Murphy

Ruth Ellen Beni

Anthony Alan Duffer

Ahmer R Syed

A liquid metal rotary connector for a vehicle steering mechanism utilizes a conductive alloy comprising Gallium, Indium, Tin and Zinc to electrically couple stationary and rotary terminals of the connector. The alloy is a liquid at ambient temperatures, and has a melting point of &#x2212;36&#xb0; C., though testing has shown that it operates satisfactorily at temperatures as low as &#x2212;40&#xb0; C. In a preferred arrangement, the rotary connector provides a two-wire connection through which power is supplied from the steering column to the steering wheel, and electronic modules located in the steering column and the steering wheel support bi-directional data communication through voltage and current modulation of the supplied power.

Liquid metal rotary connector apparatus for a vehicle steering wheel and column

An improved vertical integrated circuit device package that eliminates or reduces the need for wire bond connections and/or solder connections is provided. The package includes a vertical device having electrodes on opposite surfaces, and a compressed spring member that is used to establish compression electrical connections between the electrodes and corresponding electrically conductive elements.

Compression connection for vertical IC packages

A tin-lead solder alloy containing copper and optionally silver as its alloying constituents. The solder alloy consists essentially of, by weight, about 55% to about 75% tin, about 11% to about 44% lead, up to about 4% silver, nickel, palladium, platinum and/or gold, greater than 1% to about 10% copper, and incidental impurities. The solder alloys contain a small portion of CuSn intermetallic compounds, and exhibit a melting mechanism in which all but the intermetallic compounds melt within a narrow temperature range, though the actual liquidus temperature of the alloys may be considerably higher, such that the alloys can be treated as requiring peak reflow temperatures of about 250&deg; C. or less. The intermetallic compounds precipitate out to form a diffusion barrier that increases the reliability of solder connections formed therewith.

Lead-based solder alloys containing copper

A lead-free solder alloy consisting essentially of, by weight, 3.0% to 3.5% silver, greater than 1% to about 15% copper, the balance tin and incidental impurities, and having an effective melting range of about 215&deg; C. to about 222&deg; C. The solder alloy is noneutectic, and therefore characterized by solidus and liquidus temperatures, the former being in a range of about 215&deg; C. to about 218&deg; C., while the latter is about 290&deg; C. or more. However, the melting mechanism exhibited by the alloy is such that the alloy is substantially all melted and does not exhibit a &ldquo;mushy zone&rdquo; above the effective melting range, enabling the alloy to behave similarly to the SnAgCu eutectic alloy.

Lead-free solder alloy and solder reflow process

A tin-lead solder alloy containing copper and/or nickel and optionally silver, palladium, platinum and/or gold as its alloying constituents. The solder alloy consists essentially of, by weight, about 5% to about 70% tin, up to about 4% silver palladium, platinum and/or gold, about 0.5% to about 10% copper and/or nickel, the balance lead and incidental impurities. The presence of copper and/or nickel in the alloy has the beneficial effect of inhibiting the dissolution and leaching of silver from a silver-containing thick-film, such as a conductor or solder pad, into the molten solder alloy during reflow. In addition, solder joints formed of the solder alloy form a diffusion barrier layer of intermetallic compounds that inhibit solid-state interdiffusion between silver from a silver-containing thick-film and tin from the solder joint.

Leach-resistant solder alloys for silver-based thick-film conductors

A solder alloy containing indium, lead, silver and copper as its alloying constituents, and a soldering process employing the solder alloy. The solder alloy consists essentially of, by weight, about 50% to about 65% indium, about 0.5% to about 3.0% silver, up to about 3.0% copper, the balance lead and incidental impurities. The alloy preferably has a solidus temperature in a range of about 173&deg; C. to about 178&deg; C., and a liquidus temperature in a range of about 187&deg; C. to about 196&deg; C. As such, the alloy can be used in a reflow process with a peak reflow temperature of about 220&deg; C. to about 240&deg; C., and is therefore compatible with most circuit components and can be simultaneously reflowed with 63Sn-37Pb solder.

Solder process and solder alloy therefor

A method for solder bumping a surface-mount circuit component, as well as electrically and mechanically connecting the component to a conductor on a substrate, and the components and assemblies formed thereby. The method generally entails forming a multilayer metal bump containing discrete layers, including at least one layer of a solder alloy, a first metallic layer having a sufficiently high melting point so as not to melt or deform at the reflow temperature of the solder alloy, and a second metallic layer containing at least one metal that is soluble in the solder alloy. During reflow, the first metallic layer does not collapse, while the solder layer and the second metallic layer readily flow and subsequently bond the first metallic layer to suitable structures on the component and substrate. As a result of the reflow operation, the multilayer metal bump of this invention forms a solder connection with a graded composition, namely, an intermediate region formed primarily by the first metallic layer, and at least one end region that contains a solid solution formed of the solder layer and the first and second metallic layers.

Method of solder bumping a circuit component

A solder bumping method and structure for producing fine-pitch solder bump and which eliminate conventional process compatibility requirements for under bump metallurgy (UBM) and solder bump formation. The method generally entails forming an input/output pad on the surface of a semiconductor device, and then forming a metal layer on the input/output pad that will serve as the UBM of the solder bump. A plating seed layer is then formed on the UBM and on the surrounding surface of the device, after which a mask is formed on the plating seed layer and a via is formed in the mask to expose a portion of the plating seed layer overlying the UBM, and preferably portions of the plating seed layer not overlying the UBM. A solder material is then deposited on the portion of the plating seed layer exposed within the via. Because the via is not limited by the size of the UBM, the deposited solder material is able to cover an area larger than the metal layer, thereby increasing the amount of solder material available to form the solder bump without requiring a thicker mask.

Surface mount circuit device and solder bumping method therefor

A method by which semiconductor wafers (10, 12) can be solder bonded to form a semiconductor device, such as a sensor with a micromachined structure (14). The method entails forming a solderable ring (18) on the mating surface of a device wafer (10), such that the solderable ring (18) circumscribes the micromachine (14) on the wafer (10). A solderable layer (20, 26, 28) is formed on a capping wafer (12), such that at least the mating surface (24) of the capping wafer (12) is entirely covered by the solderable layer (20, 26, 28). The solderable layer (20, 26, 28) can be formed by etching the mating surface (24) of the capping wafer (12) to form a recess (16) circumscribed by the mating surface (24), and then forming the solderable layer (26) to cover the mating surface (24) and the recess (16) of the capping wafer (12). Alternatively, the solderable layer (28) can be formed by depositing a solderable material to cover the entire lower surface of the capping wafer (12), patterning the resulting solderable layer (28) to form an etch mask on the capping wafer (12), and then to form the recess (16), such that the solderable layer (28) covers the mating surface (24) but not the surfaces of the recess (16).

Process for bonding micromachined wafers using solder

A lead-free solder alloy suitable for forming solder joints of a surface-mount integrated circuit device, such as a flip chip. The solder alloy has a sufficiently low liquidus temperature to achieve desirable reflow properties at temperatures of 240.degree. C. and less, and is therefore compatible with integrated circuit processes. The solder alloy has a sufficiently high solidus temperature to ensure that solder joints formed with the alloy exhibit suitable mechanical properties at application temperatures up to 150.degree. C. when mounting a component to a laminate substrate. The solder alloy generally contains, in weight percent, about 7 to about 11% indium, about 2.5 to about 3.5% silver, and about 0.5 to about 1.5% copper, the balance tin and incidental impurities.

Fatigue-resistant lead-free alloy

Composite solder paste compositions adapted to be deposited using a dry film photoresist mask to form solder joints for flip chip integrated circuit devices. The composite solder paste compositions are characterized by the ability to flow at a first temperature during bumping reflow while the photoresist mask is present, yet upon subsequently reheating to a higher temperature yield solder joints capable of withstanding temperatures of 200.degree. C. and higher. As such, the present invention retains the advantages associated with using a dry film photoresist as a mask during deposition of the solder, yet results in the formation of solder joints that exhibit enhanced reliability in severe thermal environments.

Composite solder paste for flip chip bumping

A carrier device (10) is provided for transferring solder bumps (16) to a surface of a flip chip integrated circuit device (18). The carrier device (10) is equipped with cavities (12) on its surface for receiving and retaining solder material (14), by which the solder material (14) can be transferred to the flip chip (18) as molten solder bumps (16). The cavities (12) are located on the surface of the carrier device (10) such that the location of the solder material (14) will correspond to the desired solder bump locations on the flip chip (18) when the carrier device (10) is registered with the flip chip (18). The size of the cavities (12) can be controlled in order to deliver a precise quantity of solder material (14) to the flip chip (18).

Solder bump transfer device for flip chip integrated circuit devices

A terminal pattern is provided for an integrated circuit device, such as a ball grid array package or an integrated circuit flip chip. The terminal pattern is composed of a number of terminals arranged in concentric arrays, each array having a substantially circular shape and being composed of a number of terminals. The terminal pattern is composed of at least two arrays, and more typically three or more arrays. When the integrated circuit device is mounted to its intended substrate, the individual terminals of the terminal pattern each register with and are soldered to a corresponding conductor of a conductor pattern formed on the substrate. A significant advantage is that, due to the terminals of the terminal pattern being arranged in concentric arrays, a smaller maximum width for the terminal pattern is achieved than possible with a conventional rectangular terminal pattern having the same number of terminals. As such, the terminal pattern and the resulting solder joints between the terminal pattern and its corresponding conductor pattern exhibit improved fatigue life as compared to the conventional rectangular terminal pattern.

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Kokomo, IN, United States of America

Shing Yeh