Abstract: The invention relates to a method for dry cleaning or dry fluxing metallic surfaces before, during, or after a reflow soldering operation. The metallic surfaces that are dry cleaned or dry fluxed include (1) the metallic substrate on which an at least partially metallic, electronic component is to be mounted, (2) the solder paste, and (3) the metallic portions of the electronic component. The method comprises treating the metallic surface with a gaseous treatment atmosphere comprising unstable or excited gaseous species, and is substantially free of electrically charged species.

Abstract: The invention relates to a method for joining coated metallic conductors and the application of the method to production of very high density microjoints as well as to the fabrication of macrojoints. It is characteristic for the invention that the surfaces to be connected are coated with solder metal or solder alloy layers, one on the top of the other. The mating contact areas are heated for a short period of time over the temperature where the base coatings and the top coatings fuse transiently. It is essential that the base coating and the top coating cannot produce intermetallic compounds with each other and that the contact interface between them is as metallic as possible. This kind of contact can be obtained for example by chemical or electrochemical deposition. Moreover, when the topcoat is capable of protecting the base coating, for example bismuth, the joining can be performed under normal atmosphere and without any flux.

Abstract: In the production of a metallic honeycomb body for use as a metallic carrier, for supporting a catalyst, in the purification of an exhaust gas from automobiles or the like, a desired joint site for each layer constituting the metallic honeycomb body is preset, and, when a portion of contact between a metallic corrugated foil and a metallic flat foil for forming the metallic honeycomb body has reached the joint site, a brazing foil which has been cut into a predetermined length is inserted and enfolded in the contact portion.

Abstract: A method of precisely positioning a quantity of conductive spacers (e.g., spherically shaped solder balls) on respective conductive pads (e.g., copper pads) of an underlying substrate (e.g., an FR4 printed circuit board or flexible circuit member) wherein the spacers are forcibly retained within a suitable holder and, when engaged with the respective pads, reflowed to effect a plurality of positive electrical connections between the spacers and pads. Such forcible retention allows for partial extension of the spacers from the invention's carrier, which is also disclosed.

Abstract: Solder particles 220 are deposited onto metallized contacts of a direct chip attach (DCA) site located on a substrate 301. The contacts 302 are coated with a layer of flux 303. A pick up head 211 is positioned in a reservoir 201 of solder particles 220 and particles are attracted to the apertures in the end 213 of the head. The apertures have an arrangement corresponding to the footprint of the metallized contacts on the substrate. The head 211 is positioned adjacent the substrate 301 and the particles 220 released. The particles 220 stick to the flux 303 coated on the contacts 302. The particles are reflowed, leveled and again coated with flux. An integrated circuit chip is then placed on the leveled reliefs 501 and the reliefs reflowed again to attach the chip onto the contacts 302.

Abstract: A process of producing small metal bumps includes the steps of simultaneously holding small metal balls on an arrangement baseplate in the positions corresponding to those of electrodes of a semiconductor chip, a film carrier, or a substrate; aligning the small metal balls held on the arrangement baseplate with the electrodes; lightly pressing the small metal balls against the electrodes; to provisionally fix the balls to the electrodes; and pressing the provisionally fixed small metal balls to flatten the pressed surfaces of the small metal balls, and at the same time, to bond the small metal balls to the electrodes.

Abstract: A chip mounting section "H", defined on a flush surface of a substrate 1, is dissected into a plurality of subsections "E"--"E". Bond 2 is applied within the chip mounting section "H" on the flush surface of substrate 1 in a discrete manner so that a plurality of bonding bumps 2 are arranged within each region of subsection "E". A minimum clearance "L" between two bonding bumps 2, 2 in the same subsection "E" is smaller than a minimum clearance "D" between two bonding bumps 2, 2 belonging to adjacent to subsections "E" and "E". A chip 3 is mounted on plural bonding bumps 2 by applying a force thereon, thereby mashing plural bonding bumps 2 by a bottom surface of chip 3 without causing any void therein.

Abstract: The present invention relates generally to a new apparatus and method for molding metallic materials, such as, for example, solder. More particularly, the invention encompasses an apparatus that is used to form metallic interconnections, such as, for example, solder connections, such as, BGA (Ball Grid Array) or CGA (Column Grid Array) in a mold for later use to electrically or mechanically connect two devices, such as, for example, semiconductor devices. A method for forming the metallic connections that are used to electrically or mechanically connect two devices, such as, for example, semiconductor devices is also disclosed. However, these metallic interconnections in a mold could also be used to form other structures, such as, for example, heat sinks with fins, etc.

Abstract: This invention relates to a method of combining a plurality of surface mount technology components and at least one plated through-hole component on a printed wiring board. The method includes applying to a secondary side of the printed wiring board a first layer of a preselected quantity of electrically conductive adhesive and then attaching a first portion of the plurality of the surface mount technology components to the adhesive. The first layer of the adhesive is then reflowed, thereby adhering the first portion of the plurality of surface mount technology components to the secondary side of the printed wiring board. The method then continues by applying to a primary side of the printed wiring board a second layer of the first preselected quantity of electrically conductive adhesive and applying to the primary side of the printed wiring board a second preselected quantity of electrically conductive adhesive.

Abstract: In one aspect of the invention, a piston is sized to slide along a first axis within a hollow cylinder, and the piston and cylinder assembly is rotatable about a second axis with respect to a support structure. In another aspect of the invention, a container is sized to receive a bag having a mouth larger than a characteristic cross-section of an article to be deposited therein. A member supported by the container has a hole sized in accordance with the characteristic cross-section of the article, and the mouth of the bag is releasably secured to the hole so that the bag is gathered to provide an opening into the bag sized in accordance with the characteristic cross-section of the article.

Abstract: The invention provides a solder-precipitating composition containing Sn-Pb alloy powder and an organic acid salt of Pb as essential components, and capable of precipitating solder as a result of substitution between Sn contained in the Sn-Pb alloy powder and Pb contained in the organic acid salt of Pb. Further, the invention provides a mounting method including the steps of supplying a conductor on a board with a solder-precipitating composition which contains Sn-Pb alloy powder and an organic acid salt of Pb as essential components, heating the solder-precipitating composition supplied on the conductor, to precipitate solder on the conductor and pre-coat the conductor with solder, as a result of substitution reaction between Sn in the Sn-Pb alloy powder and Pb ions in the organic acid salt of Pb, mounting a device on the solder pre-coated conductor, and melting the solder layer to securely mount the device on the conductor.

Abstract: A method is available for forming a solder film on a metallic surface such as a pad of a metallic circuit of a printed circuit board and a lead frame of electronic parts which is capable of forming a precise and fine pattern. The method comprises selectively imparting tackiness to only a predetermined part of the metallic surface by use of a tacky layer-forming solution, adhering a powdered solder to the resulting tacky part, and then melting the solder by heating to thereby form a solder film.

Abstract: A method of applying bonding agents, such as solder pastes and conductive adhesives, to pad sites in the manufacture of electronic circuits uses a paste injection head. A permanent mask with cavity openings is applied around conductive pads on a carrier. The conductive pads correspond to chip attachment sites. The injection head is brought into contact with a surface of the mask, and pressure is applied to a bonding agent in the injection head. The injection head is then moved over the surface of the mask, filling cavity openings with the bonding agent. The injection head is then removed from the surface of the mask. If a solder paste is used, infrared radiation is applied to filled cavity openings to evaporate a paste flux and reflow solder to form solder balls within the cavity openings projecting above the mask. If a conductive adhesive is used, a stencil is applied to the surface of the mask prior to contacting the mask with said injection head.

Abstract: The present invention relates to a method for mounting electronic devices on a substrate by using soldering with flux which contains materials capable of ion-exchanging or ion-catching so as to catch impurity ions which seep from a solder portions, and thereby it is not necessary to have a fusing step and a cleaning step in an plating process of the method.

Abstract: A roll of tape with solder forms and methods for transferring the solder forms only or both the solder forms and portions of the tape to electronic components are disclosed. Electronic components may be any of integrated circuit chips, chip packages and printed circuit boards. Transferring solder forms to electronic components is a two-step process: (a) the solder forms are positioned and placed on a roll of tape off-line and (b) the solder forms on the roll of tape are transferred to the electronic components in an assembly line. The solder forms may be temporarily or permanently attached to the tape. In the first instance, only the solder forms are transferred. In the latter instance, tape portions are transferred to the electronic components with the solder forms. The solder forms may be attached to one side of the tape or in through-holes in the tape using either UV sensitive adhesives or cold adhesives such as solder flux.

Abstract: A method is provided for soldering a coil winding to a terminal pin. A specific quantity of solder is applied onto the terminal pin, the terminal pin having a winding end wrapped therearound. The solder, for example, can be applied by immersing the pin end into a solder bath having a temperature only slightly above the melting point of the solder. Subsequently, the solder is melted with a welding torch under a protective atmosphere only at a power and time required to achieve a soft-soldering temperature. As a result thereof, a soldering free of fluxing agent and without the high thermal stress of a welding is possible. Other embodiments include placing a ring of solder onto the terminal prior to heating. Also, a predetermined length of solder wire can be brought into contact with the terminal pin prior to heating. The invention provides a guide tube device for such a purpose.

Abstract: A composite transversely plastic interconnect for a microcarrier produces a carrier-to-substrate bond having low electrical resistance and high mechanical strength, significant bond height to mediate TCE mismatch between dissimilar carrier and substrate materials, and sufficient gap between the carrier and the substrate to permit effective post solder cleaning of the interconnect. A contact array consisting of solder balls is placed directly onto either of a carrier or a substrate interconnect surface with a stencil positioned to the chosen interconnect surface. The solder balls may have a selected melting temperature. Additionally, the solder balls may have a metallic coating, such as nickel or copper, or molten solder. The carrier and substrate are joined by mating an interconnect surface of each and applying heat. Solder paste may be applied to one of the interconnect surfaces to add additional height to the joint and compensate for lack of coplanarity between the carrier and the substrate.

Abstract: A technique for simultaneously forming large numbers of solder ball (or bump) contacts on a surface of a substrate is described. A dissolvable film carrier is provided with holes arranged in a shape to correspond to an array of contact pads on a substrate. The holes are filled with solder. The film carrier retains the solder. The carrier is placed over the surface of the substrate and is heated, causing the solder to re-flow and to wet and to adhere to the contact pads. The carrier, which resists the re-flow temperature, maintains the shape of the solder contacts while cooling. After cooling, the film carrier can be removed from around the solder contacts with a suitable solvent.

Abstract: The present invention is a brazed fitting suitable for use as a hydraulic coupling for pressurized fluids. A male component has a tapered surface which mates and creates an interface with a similarly tapered surface of a female component. A brazing material is heated to diffuse and alloy within the interface, forming a connection between the surface portions which is stronger than the metal being connected. A groove on the male component retains the brazing material in the middle of the surface portions so that after the components are joined in an interference fit, the assembly is heated and the brazing material melts in the middle of the interface and connects together the mating surfaces by diffusing and alloying. The counterbore of the female component does not require a base, and the resulting structure has improved fluid flow characteristics.

Abstract: In a method of bonding a pad on a semiconductor chip to a corresponding pad on a carrier, a wire ball is attached to the pad on the chip by bonding one end of a low melting temperature aluminum alloy bond wire to the chip pad. The wire is then broken off at the bond. A bead is formed on the chip pad by heating the ball to a temperature slightly above the melting point of the bond wire material for a predetermined period of time. The melted bead is then placed into contact with a corresponding pad on the carrier.

Abstract: An apparatus and method are described for injection molding solder mounds onto electronic devices. The apparatus has a reservoir for molten solder which is disposed over a cavity in an injection plate. The injection plate is disposed over a mold having an array of cavities therein into which solder in injection molded. The mold is disposed over a workpiece, such as a semiconductor chip or a semiconductor chip packaging substrate. The cavities in the mold are aligned with electrical contact locations on the chip or substrate. The workpiece is heated and the molten solder is forced under gas pressure into the cavity in the injection plate disposed above the array of cavities in the mold. The molten solder is forced into the array of cavities in the mold. The injection plate is advanced to slide over the mold to wipe away the excess solder above the mold at a plurality of wiping apertures in the injection plate.

Abstract: Catalytic converter carrier bodies have a jacket and adjacent layers of corrugated or smooth and corrugated metal foils wound or layered in the jacket. The metal foils contact each other and contact the jacket at connecting points, defining flow channels between the metal foils and between the metal foils and the jacket and defining brazing gaps at the connecting points. A method for brazing the carrier bodies includes initially dispersing powdered brazing material with a suitable particle size in a mixture of binder material and liquid. The flow channels are flooded with the liquid mixture for depositing the brazing material in at least some of the brazing gaps. Excess mixture is subsequently removed from the flow channels and the carrier body is then brazed.

Abstract: Solder balls are transferred onto a semiconductor device (50), for example a flip chip semiconductor device, without using solder evaporation techniques. In one form, pre-formed solder balls (36) are placed in recesses (32) formed in a transfer substrate (30). A semiconductor die (12) having a plurality of bond pads (14) is positioned with respect to the transfer substrate so that the solder balls are aligned to, and in contact with, the bond pads. The solder balls are then reflowed to form a metallurgical bond to the bond pads. One embodiment of the invention utilizes a transfer substrate made of silicon so that the coefficient of thermal expansion of the transfer substrate will closely match that of the semiconductor die, thereby minimizing solder ball alignment variances. Use of silicon as a transfer substrate material also allows the recesses to easily be made non-wettable by conventional silicon oxidation techniques.

Abstract: A domestic plumbing installation of a generally simple design which is easy to manufacture, is obtained in the following manner: a connecting end of the water-conduit element is merely pushed into a connection-receiving part and includes at least one locking notch, which extends generally perpendicularly to the direction of insertion, preferably approximately tangentially, the valve housing includes at least one locking bore extending generally perpendicularly to the direction of insertion preferably approximately tangentially to the connection-receiving part and ending in the connection-receiving part. To this end the locking notch is aligned with the locking bore; a locking pin preferably a tangential pin of solder material can be inserted into the locking bore and further into the locking notch for temporary assembly, when the tangential pin is inserted the water-conduit element is permanently secured to the valve housing by causing the solder material to melt.

Abstract: In a method for bonding bumps to leads by pressing leads installed on a carrier tape against bumps formed on a substrate, corresponding lead-bump pairs are individually bonded; particularly, one lead on the carrier and one bump on the substrate are first aligned, and then other pairs of leads and bumps are successively and individually bonded, thus performing a secure and uniform bonding action without necessity of alterations to the bumps.

Abstract: This invention presents a new soldering material comprising an indium layer formed on EFTE film for solder-mounting a semiconductor device onto a metal heat sink. This indium layer can be easily transferred onto the heat sink by pressure applied by a tool, without the aid of ultrasonic energy. This produces a highly immaculate surface of the indium layer transferred onto the heat sink, and achieves stable soldering strength of the soldered semiconductor device. This invention also offers a multi-layered soldering material comprising a thin layer of metal of which the melting point is higher than the soldering temperature, and two indium layers sandwiching said metal layer, formed on an EFTE film. This multi-layered soldering material can be easily transferred onto a metal heat sink by a pressure applying tool without the aid of ultrasonic energy resulting in the stable soldering of a semiconductor device even if it has surface irregularities, without causing an electrical leakage or short circuit.

Abstract: The bonding sheet of the present invention comprises a substrate having an opening, and a low-melting point bonding metal which closes the opening or is arranged on the peripheral portion of the opening, to project in the opening. According to a bonding sheet of the present invention, a low-melting point bonding metal is interposed between a conductor pattern of a substrate and electrode terminals of an electronic component, and is bonded by thermocompression at a low temperature without melting the low-melting point bonding metal, so that bonding of a large number of electrode terminals can be completed by a single bonding operation.

Abstract: A method for producing a high temperature, high strength bond between a ceramic shape and a metal substrate, such as joining a ceramic cap to a piston for an internal combustion engine. The composite joint is effected through the use of a ceramic preform fabricated using fibers, whiskers, platelets or sponge-like particles having the same composition as the ceramic body. The preform is joined to the ceramic shape by using a ceramic slip having a ceramic corresponding in composition with the ceramic body, with this juncture being heated to achieve a secure bond. The preform is joined to the metal substrate by first infiltrating the preform with molten material corresponding to the substrate, and then pressure bonding the infiltrated preform to the substrate after the molten material has solidified. The substrate can be metal or metal alloys. An example is given for the bonding of silicon carbide to a 300 series aluminum.

Abstract: A method of applying solder to contacts of a connector, when the contacts are spaced apart according to a given arrangement. The method includes the steps of perforating a water-soluble adhesive material to form perforations in a pattern according to the given arrangement, applying solder preforms around the perforations, positioning the adhesive material to center the solder preforms around the contacts, washing off the adhesive material with water, and heating the contacts to the flow-point temperature of the solder.

Abstract: A solder button may be attached to an elongated conductor by substantially surrounding a portion of the conductor with a mass of solder. The mass of solder may be crimped or heat welded into fixed position onto the elongated conductor, which is typically in ribbon form, with the solder being cut from a strip of solder by cutting and crimping means, the strip of solder being in transverse relation to the conductor at the crimping means. The elongated conductor, with attached solder buttons, may be attached by automated means in a single step to a pane of glass or the like.

Abstract: A vacuum interrupter whose envelope comprises a cylindrical insulated casing and top and bottom metal end bells that support movable and fixed contact rods. The cylindrical wall portion of the end shields are secured to the cylindrical wall portion of the end bells and are positioned by snap arrangement of mating deformations, preferably protruberations and mating voids.

Abstract: An apparatus and method for soldering miniaturized electrical components to the surface of PC boards. A layer of solder paste is provided, into which the contact portions of electrical component leads are pressed. The component with solder paste adhering to the leads is moved to its placement station on the board and placed thereon with the leads contacting their respective pads.

Abstract: Solder wire attached along its length to a base metal by a small quantity of solder melted at the solder-base metal juncture.

Abstract: A plug-in electrical fuse comprises a fusible wire (9) disposed within an insulating housing (1) and connected between the ends of two blade-like terminals (4) secured within and projecting from the housing. Fuses of this type are manufactured by forming a strip of terminal members from strip metal, each member comprising two spaced substantially-coplanar blade-like terminal portions interconnected at their leading ends (5) by an integral cross-bar portion, and each terminal member being integrally connected with each adjacent terminal member in the strip by an interconnecting bar of the metal strip. Fusible wire is secured to the terminal portions adjacent their rear ends to form a strip of terminal and wire assemblies, and this strip of assemblies is mounted in a strip of insulating housings with the fusible wires disposed within the housings and the leading ends of the terminal portions projecting therefrom.

Abstract: Disclosed is a method of bonding electronic components (14) to metallized substrates (21) by soldering. The solder is first deposited on an unmetallized substrate (10) in a pattern of discrete pads (11, 12, 13) corresponding to the leads (28, 29, 30) of the components to be bonded. The component leads are then placed on the pads and the solder is reflowed. The solder thereby adheres to the leads so that a controlled amount of solder will remain on each lead when the component is lifted from the substrate. The components can then be soldered to an appropriate metallized substrate.

Abstract: A method and apparatus for loading solder preforms on to the pins of a multiple pin connector. A positioning plate has open sockets in the pattern of the pins of the connector to be loaded, the sockets being sized to receive a single solder preform in each one. A slidable retainer fits into a channel below the positioning plate to partially close the sockets and retain preforms therein. Loose preforms are contained in a dam attached to the top of the positioning plate and are shaken into the sockets on a vibrator table. The dam and excess preforms are removed and the positioning plate is covered by a cover plate to hold the preforms in place. The connector pins are then inserted through slots in the retainer, through the preforms and through holes in the cover plate. The retainer is removed, allowing the preforms to drop on the pins and the loaded connector is removed from the apparatus.

Abstract: Disclosed is a method of bonding microelectronic chips to bonding surfaces utilizing thin, soft bonding material preforms. The bonding material, such as indium, is formed on a carrier strip. A portion of the material is transferred from the strip by bringing it in contact with the bonding surface and supplying pressure to the strip. The chip may then be bonded to the coated surface.

Abstract: A conductive hermetic sealing cover for a container is fabricated by disposing the cover with a superimposed preformed heat-fusible conductive ring having outer dimensions similar to those of the cover in a shallow cavity of a nonconductive supporting member, the cavity having dimensions only slightly larger than those of the cover to secure registration between the ring and the periphery of the cover. A plurality of pairs of spaced electrodes are resiliently engaged with the ring with substantially equal contact pressures and a separate pulse of current is passed between the electrodes of each pair and through the ring and the cover, thereby producing an effective spot weld between the ring and the cover adjacent each of the electrodes. The term "ring" is used herein and in the appended claims in its generic sense to include a closed loop of conductive material of any configuration corresponding to the periphery of the cover, usually round or rectangular.