Abstract: In a reflow soldering apparatus, air heated by heaters is blown by fans onto a printed circuit board. Temperature controllers that control temperature of the heaters supply operation amount thereof to a calculation unit that calculates consumed electric energy of soldering apparatus. Inverters that control revolution of fans supply a value of current to the calculation unit. A control unit supplies a coefficient of the consumed electric energy to the calculation unit. The calculation unit calculates a total amount of consumed electric energy of the reflow soldering apparatus based on the operation amount, value of current and coefficient of the consumed electric energy thus obtained. A display unit displays on an operation screen the total amount of consumed electric energy of the reflow soldering apparatus, which has been calculated by the calculation unit.

Abstract: According to this brazing method, a first base member having a non-plated surface, a metal layer for functioning as a diffusion barrier layer, a brazing foil, and a second base member having a surface are arranged in this order so that the non-plated surface of the first base member and the surface of the second base member are faced with each other. The first base member and the second base member are brazed by using the brazing foil. The cost of providing a diffusion barrier layer between the first base member and the brazing foil is thereby reduced.

Abstract: A solder joint may be used to attach components of an organic vapor jet printing device together with a fluid-tight seal that is capable of performance at high temperatures. The solder joint includes one or more metals that are deposited over opposing component surfaces, such as an inlet side of a nozzle plate and/or an outlet side of a mounting plate. The components are pressed together to form the solder joint. Two or more of the deposited metals may be capable of together forming a eutectic alloy, and the solder joint may be formed by heating the deposited metals to a temperature above the melting point of the eutectic alloy. A diffusion barrier layer and an adhesion layer may be included between the solder joint and each of the components.

Abstract: A solder is deposited on a heat sink. The solder is first reflowed at a first temperature that is below about 120° C. The solder is second heat aged at a temperature that causes the first reflowed solder to have an increased second reflow temperature. The heat aging process results in less compressive stress in a die that uses the solder as a thermal interface material. The solder can have a composition that reflows and adheres to the die and the heat sink without the use of organic fluxes.

Abstract: A method of manufacturing an orthopaedic implant device having a porous outer surface is described. In one embodiment, the implant device includes a porous layer, an intermediate layer, and a solid substrate. The porous layer is preferably bonded to the intermediate layer by cold isostatic pressing. The intermediate layer is preferably bonded by vacuum welding to the solid substrate such that the porous layer forms at least a portion of the outer surface of the orthopaedic implant device. Preferably, a diffusion bond is created between the bonded intermediate layer and the solid substrate by hot isostatic pressing. In another embodiment, a porous layer is created on an outer surface of a solid layer by selective melting. Preferably, the solid layer is bonded to the solid substrate such that the porous layer forms at least a portion of the outer surface of the orthopaedic implant device.

Abstract: A method of forming solder bumps on electrodes of a circuit board without producing bridging using a solder transfer sheet which does not require alignment includes superposing a circuit board and a solder transfer sheet having a solder layer adhered to at least one side of a supporting substrate, performing heating under pressure to a temperature lower than the solidus temperature of the solder to selectively perform solid phase diffusion bonding of the solder layer to electrodes, and peeling the transfer sheet from the circuit board. The solder layer is in the form of a continuous solder coating or in the form of a monoparticle layer of solder particles which are adhered to the supporting substrate by an adhesive layer.

Abstract: A method for securing electronic components, in particular power semiconductor components such as diodes, transistors or thyristors, and connection elements, to a substrate by pressure sintering. The method includes: applying a pastelike layer, made up of a metal powder and a solvent, to a supporting film; drying the pastelike layer; applying at least one component to the dried layer; subjecting the at least one component, the supporting film and the dried layer to pressure, as a result of which the adhesive force between the layer and the component becomes greater than that between the layer and the supporting film; lifting off the at least one component, with the layer adhering to it, from the supporting film; positioning the component, with the layer adhering to it, to the substrate; and subjecting the substrate and the component to pressure, for connecting them by sintering.

Abstract: A method for attaching a porous metal layer to a dense metal substrate, wherein the method is particularly useful in forming orthopedic implants such as femoral knee components, femoral hip components, and/or acetabular cups. The method, in one embodiment thereof, comprises providing a solid metal substrate; providing a porous metal structure; contouring a surface of the porous metal structure; placing the porous structure against the substrate such that the contoured surface of the porous metal structure is disposed against the substrate, thereby forming an assembly; applying heat and pressure to the assembly in conjunction with thermal expansion of the substrate in order to metallurgically bond the porous structure and the substrate; and removing mass from the substrate after the porous structure is bonded to the substrate, thereby finish processing the assembly.

Abstract: A method and apparatus for the formation of coplanar electrical interconnectors. Solder material is deposited onto a wafer, substrate, or other component of an electrical package using a complaint mold such that the terminal ends of the solder material being deposited, i.e., the ends opposite to those forming an attachment to the wafer, substrate, or other component of an electrical package are coplanar with one another. A complaint mold is used having one or more conduits for receiving solder material and having a compliant side and a planar side. The compliant side of the mold is positioned adjacent to the wafer, substrate, or other component of an electrical package allowing solder material to be deposited onto the surface thereof such that the planar side of the compliant mold provides coplanar interconnectors. An Injection Molded Solder (IMS) head can be used as the means for filling the conduits of the compliant mold of the present invention.

Abstract: The present general inventive concept includes a wave soldering apparatus, a soldering method using the wave soldering apparatus, and a method of forming a solder bump for a flip chip. The wave soldering apparatus includes a solder bath containing a molten solder. A nozzle is arranged in the solder bath so as to upwardly spout the molten solder toward a bottom surface of a substrate that passes an upper portion of the solder bath. A liquid that is separated from the molten solder is contained in a downstream area of the solder bath, and buoyancy is applied to the molten solder, which is adhered to the substrate, by the liquid. Since the amount of the molten solder adhered to the substrate is increased by the buoyancy, it is possible to form the solder bump to have a height sufficient to use it as a flip chip.

Abstract: A clad solder thermal interface material is described. In one example the material has a first layer of solder, a second layer of solder clad to the first layer of solder, the second layer having a melting temperature lower than the melting temperature of the first layer, and a third layer of solder clad to the first layer of solder opposite the second layer, the third layer having a melting temperature lower than the melting temperature of the first layer.

Abstract: A method for attaching a porous metal layer to a dense metal substrate, wherein the method is particularly useful in forming orthopedic implants such as femoral knee components, femoral hip components, and/or acetabular cups. The method, in one embodiment thereof, comprises providing a solid metal substrate; providing a porous metal structure; contouring a surface of the porous metal structure; placing the porous structure against the substrate such that the contoured surface of the porous metal structure is disposed against the substrate, thereby forming an assembly; applying heat and pressure to the assembly in conjunction with thermal expansion of the substrate in order to metallurgically bond the porous structure and the substrate; and removing mass from the substrate after the porous structure is bonded to the substrate, thereby finish processing the assembly.

Abstract: A method of forming a structure by a material additive process, the method comprising the steps: providing a substrate having a surface, providing an interlayer on the surface which conforms to the surface of the substrate, forming a melt pool in the interlayer, the depth of the melt pool being less than the depth of the interlayer, selectively depositing a material within the melt pool, allowing the material to solidify, and applying heat and pressure to diffusion bond the material to the substrate.

Abstract: A method having a step of heating a mass forming a braze. Before the heating step, the method includes steps of arranging the mass and the member on the support. In particular, it includes a step of positioning the mass on the support and a step of applying a first compressive force on the mass so as to compress said mass against the support, the intensity of the first force increasing up to a predetermined first value chosen so as to flatten the mass. Next, the method includes a step of positioning the member on the flattened mass and a step of applying a second compressive force to the member so as to compress said member against the flattened mass and the support, the intensity of the second force increasing up to a second predefined value, the second predefined value being lower than the first predefined value.

Abstract: A system, method, and device for applying conductive bonding material to a substrate are disclosed. The method includes providing conductive bonding material in a plurality of cavities of a mold. A total number of cavities in the plurality of cavities being greater than a total number of at least one conductive pad of a circuit supporting substrate corresponding to the mold. The conductive bonding material in the mold is heated to a reflow temperature of the conductive bonding material. At least one wettable surface is placed in substantial contact with the heated conductive bonding material in at least one cavity. The mold and the corresponding circuit supporting substrate are brought in close proximity to each other such that the heated conductive bonding material in at least one cavity comes in contact with at least one conductive pad of the corresponding circuit supporting substrate.

Abstract: A stator for a torque converter, including a pump side blade plate with a first outer circumferential portion and a turbine side blade plate with a second outer circumferential portion in contact with the first outer circumferential portion. One of the first or second outer circumferential portions includes an axially extending lip with a plurality of notches and the other of the first or second outer circumferential portions includes a plurality of radially outward protrusions disposed in the plurality of notches and the lip includes a plurality of at least partially radially inward protrusions in contact with other of the first or second outer circumferential portions and exerting force on the other of the first or second outer circumferential portions to urge the pump and turbine side plates together.

Abstract: A method for forming metallurgical interconnections and polymer adhesion of a flip chip to a substrate includes providing a chip having a set of bumps formed on a bump side thereof and a substrate having a set of interconnect points on a metallization thereon, providing a measured quantity of a polymer adhesive in a middle region of the chip on the bump side, aligning the chip with the substrate so that the set of bumps aligns with the set of interconnect points, pressing the chip and the substrate toward one another so that a portion of the polymer adhesive contacts the substrate and the bumps contact the interconnect points, and heating the bumps to a temperature sufficiently high to form a metallurgical connection between the bumps and the interconnect points. Also, a flip chip package is made by the method. In some embodiments the metallurgical connection includes an alloy of gold and tin at the interface between the bumps and the interconnect points.

Abstract: Provided is a method and apparatus for mounting a plurality of electronic components. The method comprises mounting a first electronic component on a substrate; forming a mask on the substrate to expose the first electronic component and a region of the substrate on which a solder paste is to be applied; forming a guide on a portion of the mask disposed around the first electronic component; applying the solder paste onto the substrate by using a squeezer contacting a portion of the mask disposed around the region of the substrate on which the solder paste is to be applied; removing the guide and the mask; and mounting a second electronic component on the solder paste.

Abstract: Nano-scale particle paste may be used for on-die routing and other applications using deposition and inkjet printing. A metal paste is applied to a surface of a die to electrically couple two spaced apart connection points of the die. Alternatively, or in addition, the paste may contain carbon nanotubes. The paste may be used on other surfaces as well.

Abstract: A mold fill head includes a solder delivery head and an interface portion having a compliant portion secured to the solder delivery head and a dispensing region associated with the compliant portion. The dispensing region is formed with at least one aperture configured to interface with cavities in a mold plate, the at least one aperture being in fluid communication with the solder delivery head. The compliant portion is configured and dimensioned to urge the dispensing region against the mold plate when held a predetermined distance therefrom and to substantially tolerate variations in flatness of the mold plate, variations in the predetermined distance, and/or variations in an angular orientation of the interface portion and the mold plate.

Abstract: Methods of forming a conductive structure on a substrate prior to packaging, and a test probe structure generated according to the method, are disclosed. The conductive structure includes a high aspect ratio structure formed by injected molded solder. The invention can be applied to form passive elements and interconnects on a conventional semiconductor substrate after the typical BEOL, and prior to packaging. The method may provide better electromigration characteristics, lower resistivity, and higher Q factors for conductive structures. In addition, the method is backwardly compatible and customizable.

Abstract: A method for attaching a porous metal layer to a dense metal substrate, wherein the method is particularly useful in forming orthopedic implants such as femoral knee components or acetabular cups. The method, in one embodiment thereof, comprises providing a structured porous layer; providing a dense metal substrate; providing a binding mixture; applying the binding mixture to the exterior of the substrate; placing the porous layer against the substrate such that the binding mixture is disposed there between forming an assembly; and heat treating the assembly to metallurgically bond the porous layer to the substrate.

Abstract: When a diamond is brazed to a metal substrate, while obtaining a stable joining strength, a joined interface of the diamond is not eroded to provide a good joint with a beautiful view. A brazing-filler material containing at least one selected from a group consisting of gold and silver, and copper as principal components, and further containing 0.001 to 5 mass % of vanadium is used. Preferably, a vanadium content is not more than 2.0 mass %, and more preferably not more than 0.5 mass %. Using this brazing-filler material, unidirectional solidification is performed from a side of diamond to form vanadium carbide in a joined interface in a shape of islands, and thereby an interface having a beautiful view with stable joining strength can be obtained. In addition, strong joining is possible also by a usual solidification method.

Abstract: This invention describes the roll bonding of Al and Ni-bearing Cu alloys to suitable substrates to produce self-brazing materials for the elevated temperature, aggressive environment application. The Al and Ni-bearing Cu alloy for the self-brazing layers can be obtained by cladding layers of elemental Ni and Al to Cu. The Al content in the self-brazing layers can be varied from 2 to 100%. The Ni content in the self-brazing Cu alloy can be varied from 10 to 100%. Additional alloying elements in the commercial Cu alloys such as Fe, Cr, Si, Mn, Sn and Zn are unavoidable. Trace elements in the commercial alloys such as Pb, Ag and As will also affect the brazing and shall be reduced.

Abstract: A system for joining a pair of structural members having widely differing coefficients of thermal expansion is disclosed. A mechanically “thick” foil is made by dispersing a refractory metal powder, such as molybdenum, niobium, tantalum, or tungsten into a quantity of a liquid, high expansion metal such as copper, silver, or gold, casting an ingot of the mixture, and then cutting sections of the ingot about 1 mm thick to provide the foil member. These foil members are shaped, and assembled between surfaces of structural members for joining, together with a layer of a braze alloy on either side of the foil member capable of wetting both the surfaces of the structural members and the foil. The assembled body is then heated to melt the braze alloy and join the assembled structure. The foil member subsequently absorbs the mechanical strain generated by the differential contraction of the cooling members that results from the difference in the coefficients of thermal expansion of the members.

Abstract: A method for the manufacturing or repair of a superalloy gas turbine component including a liquid phase diffusion bonding process wherein the brazing heat treatment used for the diffusion bonding of a powder material to the component is accomplished by a heat cycle that is performed on the component for another purpose. A manufacturing solution heat treatment, a pre-weld heat treatment, a post-weld heat treatment, or a rejuvenating heat treatment may be used as the brazing heat treatment. The composition of the powder material is selected so that a desired set of material properties is achieved when the powder material is subjected to the dual-purpose heat cycle. In one embodiment, a 50/50 mixture of AM775 and IN939 powder is diffusion brazed to an IN939 superalloy component using a heat treatment which also functions as the post-casting solution heat treatment for the IN939 component.

Abstract: A system and method of joining together first and second electric terminals includes providing the second terminal with an aperture extending therethrough and a notch therein. The first and second terminals are positioned in overlapping relationship with one another so the aperture overlaps the first terminal to provide access to the first terminal through the second terminal, and so the notch overlaps the first terminal. Heat is applied to the first terminal through the aperture in the second terminal to heat the first and second terminals. The end of a solder wire is positioned in engagement with the notch of the heated second terminal to locate the solder wire with respect to the terminals and to melt the solder wire to form a solder pool that contacts the first and second terminals.

Abstract: A process for welding superalloys, and particularly articles formed of gamma prime-strengthened nickel-base superalloys whose chemistries and/or microstructures differ. The process entails forming the faying surface of at least one of the articles to have a cladding layer of a filler material. The filler material may have a composition that is different from both of the articles, or the same as one of the articles. The cladding layer is machined to promote mating of the faying surfaces, after which the faying surfaces are mated and the articles welded together. After cooling, the welded assembly is free of thermally-induced cracks.

Abstract: A solder bump fabrication method and apparatus. The method comprises following steps. First, a printed circuit board, having a plurality of devices, is provided. A material is formed on the printed circuit board, and it is disposed between pins of the devices so that the material prevents the devices from short-circuiting due to the solder bumps. Then, the solder bumps are formed on the pins of the devices so that the devices are fixed on the printed circuit board. The printed circuit board is passed through an infrared oven to melt the solder bumps. Finally, extra solder bumps other than those attached to the device pins are removed, and the material separates the solder bumps attached to the pins of the devices so that the devices are prevented from short circuiting. In addition, the apparatus is provided with a plurality of through holes corresponding to gaps between the pins on the printed circuit board.

Abstract: The invention concerns a method whereby a soldering joint is applied on one of the surfaces of a collector plate (2, 3) before inserting the ends of the tube to be assembled thereto, in the form of a flexible adhesive previously perforated to correspond to the holes (20) of the plate.

Abstract: Reaction-brazing of tungsten or molybdenum metal bodies to carbonaceous supports enables an x-ray generating anode to be joined to a preferred lightweight substrate. Complementary surfaces are provided on a dense refractory metal body and a graphite or a carbon-carbon composite support. A particulate braze mixture comprising Hf or Zr carbide, Mo or W boride, Hf or Zr powder and Mo or W powder is coated onto the support surface, and hafnium or zirconium foil may be introduced between the braze mixture and the refractory metal body complementary surface. Reaction-brazing is carried out at or near the eutectic point of the components, which may be influenced to some extent by the presence of carbon and boride. Heating to about 1865° C.

Abstract: A brazing product, e.g. a brazing sheet product, having an aluminium layer made of an aluminium alloy comprising silicon in an amount in the range of 2 to 18 weight %, and a layer comprising nickel on the outer surface of the aluminium layer such that taken together the aluminium layer and all layers exterior thereto form the filler metal for a brazing operation. The filler metal has a composition containing at least one element: (i) with a smaller exchange current density for the Hydrogen Evolution Reaction (“HER”) than nickel and/or (ii) such that the electro-chemical potential difference between particles of Ni-aluminide(s) of the filler and the aluminium alloy matrix of the filler is reduced. The filler metal's mol-ratio of Ni to such element(s) is in the range of 10:(O.3-30). The invention also relates to a method of manufacturing a brazed assembly using the brazing product, and to a brazed assembly comprising at least one component made of the brazing product.

Abstract: Recesses are formed in a solder transfer plate and filled with solder. Core bumps of an electronic component are brought into contact with the solder in the recesses, and thereby the metal contained in the solder in the recesses is melted. The electrical connecting structure, on which the core bump is coated with solder, is formed by separating the electronic component from the transfer plate.

Abstract: An apparatus for placing an array of solder balls on a substrate includes a carrier plate having an array of holes therethrough. Each hole is capable of holding a solder ball. A ball placement head having an array of pins is aligned with a desired pattern of solder balls held by the carrier plate. The array of pins push the pattern of solder balls through the holes in the carrier plate onto the substrate.

Abstract: Disclosed is a method of manufacturing an assembly of components joined by brazing, comprising the steps of:

Abstract: A micro-optical component comprises an optical element for interacting with an optical beam and a mounting structure for attaching the optical element to an optical bench. This optical element is solid phase welded to the mounting structure. Solid phase welding has advantages in that it can be performed at lower temperatures than most soldering, even some eutectic soldering. Solid-phase welding, however, is much more robust during subsequent temperature cycling. This is especially important when the optical components undergo subsequent high temperature cycling.

Abstract: A method for applying brazing material to metal structures is used, in particular, for honeycomb bodies of exhaust gas catalytic converters. The brazing material is applied in the form of a powder and is firmly held to the metal structures through the use of an adhesive material acting as a bonding agent, binder or adhesion promoter. The adhesive material that is used to firmly hold the brazing powder assumes two different states with respect to its adhesive action during the production process of the metal structure. A first state is less adhesive and a second state is more strongly adhesive. The adhesive strength can be selected or adjusted as a function of external conditions, especially temperature. Therefore, at a given time the adhesive material can be put into a state which is suitable for each production step, as a result of which the brazing material quality is increased and the production process is simplified.

Abstract: A method for joining a multiplicity of multi-alloy solder columns to an electronic substrate and the structure formed by such method are disclosed. In the method, a mold plate equipped with a multiplicity of cavities is first filled by an injection molded solder technique with a high temperature solder forming a multiplicity of solder columns. The mold plate is then sandwiched between an extraction plate and a transfer plate by utilizing a multiplicity of displacement means equipped in the extraction plate to displace the multiplicity of solder columns from the mold plate into a multiplicity of apertures equipped in the transfer plate. The multiplicity of cavities in the transfer plate each has a straight opening and a flared opening. The flared opening is then filled with a low temperature solder paste to encapsulate one end of the high temperature solder column.

Abstract: This invention provides an improved method of projection welding which enables the sound welding of high-carbon, and high-tension low-alloy steels.

Abstract: A method of forming solder bumps on pads formed on a surface of a base material includes the steps of supplying solder to a template having a number of through holes formed to correspond to the pads of the base material respectively so that the through holes are filled with the solder, the template having an upper side and an underside, scraping the sides of the template with doctors to remove an excessive amount of solder, and opposing the template to the base material so that the pads are aligned with the through holes respectively, covering the side of the template opposite to the base material with a pressure housing and increasing pressure in an interior of the pressure housing so that a difference in pressure between an exterior and the interior of the pressure housing extrudes the molten solder from the template to the pad side of the base material.

Abstract: A vacuum-tight cable feedthrough device includes a metallic first flange that is penetrated by a slot. Passing through the slot is a flat stripline cable that includes a plurality of conductive signal channels encompassed by a dielectric material on whose upper and lower surfaces is disposed a conductive material includes a ground. The stripline cable is sealed within the slot to provide a substantially vacuum-tight seal between the cable and the first flange. In a preferred embodiment, the cable feedthrough device includes a plurality, at least 16, of stripline cables. In a further preferred embodiment, the device includes a second flange and a bellows sealably connecting the first and second flanges, thereby providing a substantially vacuum-tight, flexible housing for the plurality of cables.

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: 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: To present a method and apparatus for forming favorable solder bumps on a substrate of electronic component or the like, in which metal paste is applied on the lower surface of solder balls attracted by a suction tool, and the solder balls are positioned to contact with recesses having the electrode in the bottom, so that the metal paste adhered to the solder balls is adhered to the top of the recesses. Next, the solder balls are moved reciprocally in the vertical direction or horizontal direction. As a result, the metal paste adhered to the top of the recesses is collected to fill up the recesses. Then, the solder balls are put on the top of the recesses, and heated and fused, and solder bumps are formed.

Abstract: An apparatus for placing an array of solder balls on a substrate includes a carrier plate having an array of holes therethrough. Each hole is capable of holding a solder ball. A ball placement head having an array of pins is aligned with a desired pattern of solder balls held by the carrier plate. The array of pins push the pattern of solder balls through the holes in the carrier plate onto the substrate.

Abstract: The disclosed invention provides for a method of manufacturing solder columns for particular use in attaching substrates to a printed circuit board. The method results in columns of homogeneous composition and thus overcomes problems associated with the phenomena of segregation. The method includes the steps of forming particles of the metal composition to be used for the columns from a molten source of the composition. The solid particles are then formed into segments of homogeneous composition by drawing ingots of the composition into wire and severing the wire into segments.

Abstract: A brazing transfer alloy tape which includes a carrier layer that may be easily seen by the operator so that it may be removed before brazing is provided. The brazing tape consists essentially of a brazing alloy layer having two opposing surfaces, a pressure sensitive adhesive disposed on one of the two opposing surfaces of the brazing alloy layer for adhering the brazing tape to the object to be brazed, a backing layer disposed on the pressure sensitive adhesive, and a visually distinctive carrier layer attached to the other of the two opposing surfaces of the brazing alloy layer opposite the pressure sensitive adhesive. The carrier layer is such that it is easily noticeable by an operator before brazing. This is accomplished, for example, by forming the carrier layer from a colored or opaque material, or from a material having a visually distinctive pattern.

Abstract: An apparatus for placing an array of solder balls on a substrate includes a carrier plate having an array of holes therethrough. Each hole is capable of holding a solder ball. A ball placement head having an array of pins is aligned with a desired pattern of solder balls held by the carrier plate. The array of pins push the pattern of solder balls through the holes in the carrier plate onto the substrate. The invention is also directed to a solder ball dispenser for dispensing solder balls to a plate having an upper surface with an array of holes formed therein. The solder ball dispenser includes a plate support to support the plate such that the upper surface is tilted at an angle from horizontal, a ball feed device to provide solder balls to the plate, and a solder ball retainer. The solder ball retainer is movable across the upper surface of the plate for controlling a speed at which the solder balls move across the plate.

Abstract: The present invention discloses a method and apparatus for forming solder bumps by a molten solder screening technique in which a flexible die head constructed of a metal sheet is utilized for maintaining an intimate contact between the die head and a solder receiving mold surface. The flexible die head, when used in combination with a pressure means, is capable of conforming to any curved mold surface as long as the curvature is not more than 2.5 .mu.m per inch of die length. The present invention further provides a method and apparatus for filling a multiplicity of cavities in a mold surface by providing a stream of molten solder and then intimately contacting the surface of the molten solder with a multiplicity of cavities such that the molten solder readily fills the cavities. The apparatus further provides means for removing excess molten solder from the surface of the mold without disturbing the molten solder already filled in the cavities.

Abstract: Disclosed is a solder injection mold apparatus and method for providing solder balls to a printed circuit board substrate using the solder injection mold apparatus in the plastic ball grid array (PBGA). The solder mold through holes are chamfered at entry and at exit ends to assist in receipt of molten solder and the formation and transfer of solder balls to lands on the substrate. A blind recess is provided in the second major surface of the mold, i.e. the side facing the substrate, in order to accommodate electronic components mounted thereon. Solder balls are delivered and metallurgically affixed to the lands in a process that requires only one reflow, leaving the through holes clean of solder and the mold ready for reuse. The material of which the substrate, mold and base plate are comprised is selected to be non-wettable by solder and mutually compatible with respect to CTE when exposed to temperatures of molten solder.