Delphi Technologies, Inc.

Delco Electronics Corporation

Bradley H Carter

Shing Yeh

Scott David Brandenburg

John Karl Isenberg

Frans Peter Lautzenhiser

Dwadasi Hare Rama Sarma

Curtis Wayne Melcher

Kevin J Hawes

Carl William Berlin

Otto Muller-Girard, Jr

Dwadasi H Sarma

Frank Stepniak

Jason C Short

David Jay Vess

Jerome Anthony Schneider

Cynthia J Baron

Donald A Ozogar

Scott A Williams

Lynda G Flederbach

A fuel injector wherein a cylindrical surface supports an electrical heating structure covering 360&#xb0; or almost 360&#xb0; of the surface for heating fuel. The structure comprises a first dielectric layer adhered to the surface; a thick film resistance heating element; a second dielectric layer; spaced-apart first and second conductor pads, wherein the first conductor pad is disposed in contact with a dielectric layer and a first end of the heating element, and wherein the second conductor pad is disposed in contact with a dielectric layer and a second end of the heating element. Another dielectric layer may be disposed over the preceding layers and the first and second conductor pads and having first and second windows formed therein for access to the first and second conductor pads. The resistance heating element may selectively be trimmed by overprinting in a pattern one or more times to improve the uniformity of heating.

Fuel injector with a trimmable heater and an increased heater contact area

An improved electrical printed circuit exhibiting a combination of enhanced solderability and outstanding adhesion with a dielectric substrate includes a stack of two different types of conductive films. The stack includes a first conductive film that is printed onto the substrate with an ink that has been specially formulated to achieve enhanced adhesion with the substrate, and a second film that is applied over the first film using an ink that has been specifically formulated to achieve enhanced solderability.

Method for improving the thermal cycled adhesion of thick-film conductors on dielectric

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 thick-film paste for printing thick-film circuit elements, including solder stops, conductors, resistors and capacitors, and a method for using the paste. The paste has a composition that includes an organic vehicle, a filler material that contributes the desired electrical and/or material properties to the thick film fired from the paste, and an additive that is insoluble in the organic vehicle and contributes pseudoplastic Theological properties to the paste during printing. The additive also preferably evaporates, burns off, sublimates or is otherwise removed below the firing temperature of the paste.

Thick-film paste with insoluble additive

A method by which a conventional circuit trace (,) is modified with a layer (,) of high-conductivity solder alloy to yield a high-current circuit trace (,) for high-current routing on a substrate (,). The method generally entails the use of a solder composition that contains a dispersion of metal particles (,) in a solder alloy (,). The metal particles (,) are selected on the basis of having a higher electrical conductivity than the solder alloy (,), and are present in sufficient amounts so that the electrical conductivity of the solder composition is significantly higher than that of the solder alloy (,). The solder composition is deposited on a conductor (,), and then reflowed to form a conductive layer (,) on the conductor (,). The metal particles (,) remain as a discrete dispersion within the conductive layer (,) in order to suitably promote the conductivity of the layer (,). The solder composition is preferably deposited in an amount sufficient to increase the current-carrying capacity of the resulting circuit trace (,) for high-current routing on the substrate (,), e.g., in excess of six amps.

High-current circuit trace and composition and method therefor

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

The invention includes the discovery that the addition of a thermosetting polymer to a thick-film conductor formulation including a thermoplastic polymer will substantially retard the spreading of the thick-film conductor ink upon firing of the printed conductor. The thermosetting polymer may be from the family of allylic esters, for example poly(diallyl phthalate). The invention also includes the discovery that the thermosetting resin can be dissolved with an organic solvent to form an additive so as to uniformly distribute the thermosetting polymer within the thick-film conductor formulation including the thermoplastic polymers. Preferred organic solvents include alcohols with a weight ratio of thermoset-to-organic solvent ranging from about 1:1.5 to about 1:3.

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Kokomo, IN, United States of America

Bradley H Carter