Abstract: A flip chip bonding method including steps of applying a pressure and a heat and applying an ultrasonic wave in a plurality of directions or along a circular locus for connecting solder bumps, which are formed on one or both of a connecting pad of a semiconductor element or a connecting pad of a wiring board, whereby flip chip bonding is performed without using flux, a drop of yield and deterioration of reliability are improved.

Abstract: A brazing method for joining to or more pieces of metal together includes running a molten brazing solder into a space between the pieces, heating at least the adjacent surfaces of the pieces to be joined to brazing temperature in a reducing atmosphere and preheating at least the adjacent surfaces to about 600° C. in an oxidizing atmosphere prior to said heating to the brazing temperature.

Abstract: A method is provided for treating cooperating, juxtaposed substantially uncoated alloy substrate surfaces in preparation for brazing, for example an inner wall of the radially outer open end of a turbine engine blading member with the rim of an end plate or tip cap. The method includes treating at least one of the cooperating surfaces with a reducing gas comprising halogen gas for a time and at a temperature, for example 1-6 hours at 1650-1950° F., sufficient to remove any surface debris, for example oxides, and to deplete the alloy substrate surface of the total of elements selected from Al and Ti to a level of less than about 1 weight %. Depletion is to a depth in the surface which avoids intergranular attack of the substrate alloy surface. For example, the depth is no greater than about 0.0015″. Then the cooperating surfaces are brazed together.

Abstract: A method of attaching a lid with at least a metallic surface thereon to a substrate to enclose a surface acoustic wave electronic circuit using a fluxless solder preform having an undesired oxide surface and associated with the metallic surface on the lid and in superimposed and abutting relationship with a gold seal ring surrounding the electronic circuit to form a unit that is heated in a furnace having a hydrogen atmosphere such that the hydrogen removes any undesired oxide surfaces from the solder preform and the metallic surface on the lid by combining with the oxygen therein to form moisture so as to remove any oxide surfaces from the solder preform and the lid metallic surface and enable a complete bonding of the fluxless solder preform with the gold seal ring and the lid metallic surface thereby forming a hermetically sealed package.

Abstract: An improved method of manufacturing a piezoelectric element and an improved piezoelectric element are provided. The improved method comprises the steps of causing a gas discharge in a predetermined discharge gas at approximately atmospheric pressure and generating an excited active species of the discharge gas as a result of the gas discharge. Then, at least one of a connecting surface of an electrode formed of a piezoelectric piece on a piezoelectric resonator and a connecting portion of a lead terminal are exposed to the excited active species, whereby the exposed connecting portions are surface treated. Finally, the electrode and the lead terminal are connected together, and at least the electrode and the lead terminal are sealed in a case. The improved piezoelectric element is formed by this process and uses less solder and is more stable than prior art piezoelectric elements.

Abstract: The invention relates to a method and apparatus to use nitrogen, or any other inert gas, or a reducing gas as a process gas to reflow and planarize solder paste in a single heating step. The inert gas may also be used to cool the solder paste after reflowing. According to one method soldered paste is printed onto the printed circuit board with conventional methods employing a mask or stencil. A mesh, die, or mold element having a plurality of openings therein is lowered onto the soldered paste and the printed circuit board is reflowed and planarized in a single heating step. Once the paste is applied, the parts are reflowed and planarized in a single, brief, thermal excursion. The heated mesh is lowered into the solder paste causing the paste to wick through the mesh forming a meniscus. A hot gas knife is arranged to plane the meniscus of the solder paste off of the mesh. An inert, nitrogen, or reducing gas is diffused through the knife to prevent oxidation.

Abstract: A welding process for welding a Cu material to a Ti material includes interposing a tertiary component between the Ti material and the Cu material. The tertiary component is of a type of metal that, with Cu, forms a compound which is liquified at a temperature below the eutectic temperature of Ti and Cu. The above materials are heated and welded at temperature of (700 through 887° C.). The temperature selected is below the eutectic temperature of the Ti and Cu. The finished material forms a sputtering backing plate for a sputtering. A target member, bonded to the Cu material side of the backing plate, completes the sputtering target. In one embodiment, the proportion of the tertiary metal is achieved by controlling a thickness of the tertiary metal deposited on the Cu material. In another embodiment, the proportion of the tertiary metal is achieved by controlling the thickness of a layer of powder of the tertiary material deposited between the Cu and Ti materials.

Abstract: The present invention provides a joining, brazing or soldering material wherein solderability is effectively improved without using a flux, and a production method thereof. In production of a joining material, a halogen compound is mixed, a film is formed on the surface of a solder molding or the surface of a solder molding is halogenated. In production of a joining material, a halogen compound is added to a solder melt, a film of a halogen compound is formed on the surface of a processed joining material, or the surface layer of the processed joining material is converted to a halogen compound layer by halogenation. Film formation or surface treatment may be carried out either a dry or wet method.

Abstract: A method and apparatus for placing and attaching solder balls to a substrate having conductive pads in a predetermined pattern is disclosed. The substrate is placed on a carrier plate. An alignment plate having holes corresponding to the predetermined pattern is mated to the carrier plate with its holes aligned with the predetermine pattern on the substrate. Solder balls are loaded into each hole of the alignment plate. The solder balls may be loaded with a vacuum plate which uses vacuum to pick up solder balls in the predetermined pattern and place them over the holes on the alignment plate. The vacuum is released for dropping the balls in the holes of the alignment plate. Alternatively a shutter plate having holes corresponding to the holes on the alignment plate is fitted on the alignment plate and afforded slidable movement between an offset position and an aligned position. A ball is loaded in each hole in the shutter plate when it is in its offset position.

Abstract: A method for joining well and other oilfield tubulars by amorphous bonding comprises the steps of positioning a body of amorphous material (16) between adjacent and surfaces of a pair of oilfield tubulars (3, 4) that are to be joined and using induction heating to melt the amorphous material and create on cooling a metallurgical bond between the tubulars (3, 4). Throughout the heating and bonding process the tubulars (3, 4) are fixed in axial alignment with each other using clamp means which include a mandrel (1) which is inserted into the interior of the tubulars (3, 4) so that the bonding process can be performed in a sealed chamber (17, 18) which is filled with an inert gas.

Abstract: A method of forming hydrogen fluoride (HF), to allow fluxless soldering, from a solid source such as potassium hydrogen fluoride (KF.HF) using a specialized apparatus, including a cartridge which is heated in a controlled atmosphere apparatus. The gaseous reaction product, HF, may be extracted from the apparatus either by itself or in a carrier gas (such as argon or nitrogen). The solid reaction product, potassium fluoride (KF), is an inert material which remains in the cartridge. The combination of the cartridge and KF may be safely disposed of as a unit or refilled with KF.HF under controlled conditions.

Abstract: A piezoelectric resonator is provided which is formed of an element piece. This element piece further includes a piezoelectric material and an electrode formed on the surface of the piezoelectric material. A plug for mounting the element piece and a case for housing said element piece in an air-tight manner are also provided. The surface of the element piece is coated with a resin film formed from an excited active species of an organic compound generated through a gas discharge in a predetermined discharge gas at approximately atmospheric pressure. A method of manufacturing a piezoelectric resonator is also provided, which comprises the steps of first mounting the element piece on the plug. Next, a gas discharge in a predetermined discharge gas is produced at approximately atmospheric pressure and an excited active species of an organic compound which is a liquid or a gas at room temperature is generated as a result of this gas discharge in a gas discharge region.

Abstract: Process for remelting a contact surface metallization (13) applied to a strate (10) in an inert or reducing medium, wherein the medium (18) is formed as alcoholic medium whose boiling point is the same as or above the melting point of the contact surface metallization (13), the medium (18) is applied to the contact surface metallization (13) applied to a contact surface (11, 12) of the substrate (10) outside the inert or reducing medium in such a way that the contact surface metallization (13) is screened with respect to the environment, and the medium (18) is tempered to a temperature which is the same as or higher than the melting point of the contact surface metallization (13).

Abstract: A method of producing a semiconductor chip on a chip carrier includes preparing a semiconductor chip having opposite front and rear surfaces and an active element on the front surface, applying solder to the rear surface of the semiconductor chip to a prescribed thickness, picking up the semiconductor chip with a collet with the rear surface facing away from the collet and exposing the solder layer to a reducing atmosphere to remove an oxide film on the surface of the solder layer, adhering the semiconductor chip to a chip carrier via the solder layer by applying heat and by applying pressure to the semiconductor chip with the collet, and cooling the chip carrier to room temperature while pressing the semiconductor chip against the chip carrier.

Abstract: The invention provides a method of splicing rolled plates with each other, including the steps of (a) positioning a rear end portion of a leading rolled plate above a front end portion of a following rolled plate by a distance slightly greater than a diameter of a cylindrical cutter having a rotation axis extending in a width-wise direction of the leading and following rolled plates, the positioning being carried out while the leading and following rolled plates are being transferred, (b) cutting an upper surface of the front end portion of the following rolled plate with the cylindrical cutter only within a region at which the following rolled plate is to be spliced with the leading rolled plate, the cutting being carried out in a direction F in which the rolled plates are being transferred, (c) blowing a first reducing flame to the upper surface being cut from above the upper surface in the direction F while the step (b) is being carried out, (d) cutting a lower surface of the rear end portion of the leadin

Abstract: A method for pretreating a solder surface for fluxless soldering is disclosed. The method uses a noble fluorine gas to remove surface oxides from solder surfaces, without the use of external stimulation. A noble fluorine gas is suffused across the solder surface to reduce or eliminate or chemically convert the surface oxides. The process can take place at atmospheric pressure and room temperature. A simple belt driven transport may be used to move the parts past a nozzle which emits the vapor in a system similar to a conventional solder reflow machine.

Abstract: A fluxless soldering method utilizing a strongly internally bonded fluorine containing gas such as hydrogen fluoride (HF). The solder surface is exposed to the gas in place of a flux treatment, resulting in a modified surface layer which allows reflow or joining for an extended period.

Abstract: The present invention discloses a novel, moisture-free atmosphere for brazing carbon steels that provides good braze flow and brazed joint quality with minimum or no formation of soot on brazed joints. According to the present invention, carbon steels are brazed in continuous furnaces using a moisture-free atmosphere containing a mixture of three gases including nitrogen, hydrogen, and carbon dioxide. The key features of the invention involve (1) formation of moisture, which is needed to facilitate braze flow and to minimize formation of soot on brazed joints, in-situ in the heating zone of the furnace by the reaction between hydrogen and carbon dioxide and (2) reduction in the overall amount of a reducing gas required for brazing carbon steels by keeping moisture out of the cooling zone.

Abstract: A method of hot pressure welding of hot steel stock, in which the ends of the steel stock are descaled mechanically and pressure joined under a reducing flame. Since re-oxidation after descaling is prevented and the feasible temperature for hot pressure joining is maintained by the reducing flame, the joining is accomplished firmly and strong joints are obtained.

Abstract: The invention relates to a method for soldering electronic components to printed circuit boards or other elements to be connected by soldering, as well as suitable continuous soldering systems. The use of electronic modules, designed in the form of printed circuit boards populated with pluggable, mountable, or surface-mountable electronic components (Surface Mounted Devices, SMDs), which must be then soldered, is growing steadily. To manufacture these modules, suitably prepared printed circuit boards are populated with the corresponding components, the latter are held in place possibly with an adhesive or soldering paste in preparation for the soldering process, and finally the printed circuit boards and the components are connected together permanently and conductively by a soldering process. This soldering process is performed under low pressure and under the plasma action of a special process gas.

Abstract: A solder composition is applied to the pins of an electronic component. The pins of the component are brought into contact with solder at a soldering station having a bath exposed to a controlled atmosphere of low oxygen content maintained in a hood enclosing at least the surface of the bath. The controlled atmosphere is comprised of at least one neutral gas and a gaseous silicon hydride whose content is between 50.times.10.sup.-6 and 2.times.10.sup.-3 of the volume of the controlled atmosphere. The controlled atmosphere is produced:a) by introducing into the hood the neutral gas to bring the residual oxygen content to less than 200 ppm, thenb) by introducing into the hood the neutral gas and the silicon hydride with a content greater than four times the residual oxygen content in the controlled atmosphere, at the end of step a).

Abstract: A light beam heating system is suited for use in performing local heating. The light beam heating system includes a light source for emitting light, an optical lens assembly for converging the light emitted from the light source on an object to be heated, and a gas cylinder for supplying shielding gas towards the object via a gas regulator, a gas valve, and a gas nozzle. During heating, the oxygen concentration of an atmosphere around the object is maintained to less than 5%. Preferably, the shielding gas is supplied to the object via a temperature regulator so that the shielding gas may be heated to a desired temperature prior to the heating of the object.

Abstract: A method of cleaning a metal surface includes covering the portion of the metal surface with a cleaning tape. The cleaning tape is chromium in combination with a fluoride ion source bound together by fibrillated polytetrafluoroethylene. This is applied to the portion of the area to be cleaned and is subject to heat treatment at about 1800.degree. F. and a reducing atmosphere of preferably hydrogen. This effectively cleans only the area covered by the tape. Further, the tape and binder format acts to force fluoride ions into the cracks on the surface providing a significantly improved cleaning operation.

Abstract: A muffle furnace assembly for brazing aluminum heat exchanger workparts comprises a tubular muffle having a workpart conveyer extending therethrough. A pair of fans disposed inside the muffle circulate high temperature atmosphere through the workparts. The muffle is surrounded by an insulative outer shell spaced to form an interstitial cavity therebetween. High temperature combustion gasses are directed into the interstitial cavity and flow in a helical path about the muffle. Louvers are provided in the muffle, between the workparts and the fans, for regulating the amount of inert gas flow within the muffle. Inlet and exit vestibules usher workparts into and out of the furnace assembly to minimize oxygen contamination within the muffle.

Abstract: An electronic package which includes a rigid first substrate (e.g., ceramic) having a plurality of conductive pins spacedly located therein. These pins each include one end portion extending below an undersurface of the substrate for positioning and electrically coupling within a second substrate (e.g., printed circuit board), while also including an opposite end portion which projects from an opposite, upper surface of the first substrate. These upwardly projecting end portions are designed for accommodating, in stacked orientation, a plurality of thin film, flexible circuitized substrates thereon, each of these substrates being electrically coupled to a respective pin, if desired, using a solder composition.

Abstract: A method for manufacturing heat-radiative substrates on which semiconductor devices such as ICs and transistors are mounted and packages using the substrates, wherein a plurality of CuW or CuMo composite materials obtained by the infiltration method or the mixed powder sintering method are joined together with Cu interposed therebetween. Accordingly, the remaining empty holes within the CuW or CuMo materials are filled sufficiently with Cu, allowing high-quality packages having a successful thermal characteristic to be obtained.

Abstract: A process for welding stainless steel tubing in the presence of an inert gas comprising a silicon base gas, in particular silane SiH.sub.4. During the welding operation, a suitable quantity of silicon is deposited by chemical vapor deposition at the weld joint to significantly improve the corrosion resistance of the weld.

Abstract: A method for bonding a solder wire is provided wherein a lower ball end of a material solder wire is first bonded to a first bonding portion of a workpiece. Then, the material solder wire is thermally cut to provide a solder wire segment held bonded to the first bonding portion and having an upper ball end. Finally, the upper ball end is bonded to a second bonding portion of the workpiece. All of the wire bonding process steps are performed in an oxygen-free atmosphere to prevent oxidation of the solder wire.

Abstract: A fluxless soldering process comprising the steps of: preparing first and second members to be bonded by soldering, the first member having a bonding surface with a higher solder-wettability and the second member having a bonding surface with a lower solder-wettability; placing the second member with the bonding surface thereof facing upward, a solder foil on the bonding surface of the second member, and the first member on the solder foil and with the bonding surface thereof facing downward, to form an assembly; heating the assembly in a reducing atmosphere to fuse the solder foil, thereby forming a molten solder between the first and second members; and cooling the assembly to solidify the molten solder, thereby bonding the first and second members.

Abstract: A braze paste is disclosed for brazing superalloys together which includes an organic binding system, a major amount of a nickel, cobalt, gold, silver, copper or palladium based braze alloy and ground polytetrafluoroethylene. The braze paste can be used to braze superalloys together without prior nickel treatment. In the brazing step, the polytetrafluoroethylene decomposes and forms fluoride ions which in turn acts on any oxide that may form during the brazing step to remove the oxide and permit a good braze between the metal objects.

Abstract: A bonding apparatus comprises a base (16) for supporting a printed circuit board (7), an atmosphere cover (1) which has a concavity (1c) covering a semiconductor device (5) mounted on the printed circuit board (7) and which is formed of laser light transmitting material, driving means (1j) for moving the atmosphere cover (1) upwards and downwards related to the base (16), pressing means (2) and (3) provided in the atmosphere cover (1) for pressing the semiconductor device (5) toward the printed circuit board (7), and laser heating means (9) for bonding a lead terminal (6) of the semiconductor device (5) with a junction (7a) of the printed circuit board (7).

Abstract: A method is provided to braze aluminum materials to each other, the method comprising a step of producing a fluoride gas-containing atmosphere within a brazing oven. The method further comprises a step of brazing the aluminum materials, by heating said materials within said atmosphere melts. The fluoride gas-containing atmosphere is produced in the soldering oven: by introducing an inert gas and the fluoride gas through different passages; by introducing into the oven a mixture of the inert gas and the fluoride gas; or by heating a fluoride in a receptacle which is placed in the oven so as to gasify the fluoride within the oven.

Abstract: The fluxless bonding in a reducing atmosphere of integrated circuit contacts containing copper is enhanced using a layer of 200 to 1500 Angstrom thick palladium which inhibits copper oxide formation before fusion and reduces all oxides to promote wetting during fusion.

Abstract: A method of carrying out hot pressure welding of hot steel stock is disclosed, which is effective for achieving a continuous hot rolling line. The hot steel stock to be joined is subjected to butt joining or lap joining in a reducing atmosphere under pressure while under hot conditions.

Abstract: A method for forge welding or the like of a first and a second metal part, wherein at least one joint is established between opposed bounding surfaces on the two parts to be joined, and wherein preferably a reducing gas is passed through the joint or joints before the parts are pressed together. In order to make the weld less sensitive to remaining oxides, the bounding surfaces are provided with generally matching corrugations of somewhat different height.

Abstract: Disclosed is a method for preventing the oxidation of a lead frame in a bonding system comprising the steps of introducing a first atmospheric gas toward a bonding portion of a lead frame along a surface of the lead frame and supplying a second atmospheric gas to shield the bonding portion from contact with ambient air simultaneously with the introduction of the first atmospheric gas.

Abstract: A ferric article is brazed by a copper solder at a temperature of or higher than 1,100.degree. C. in a heat-treatment furnace, parts of the article which are desired to be carburized, are carburized simultaneously with the brazing by covering with organic materials such as an old newspaper and the like.

Abstract: A method of joining components to a substrate by reflow soldering with non-rosin-based flux containing solder is disclosed comprising heating the solder in the presence of the components in a low oxidizing atmosphere.

Abstract: A process for brazing non-ferritic steel surfaces such as nickel chromium or stainless steel to which a suitable brazing alloy such as copper has been mechanically attached which includes the steps of instantaneously elevating the surface of the stainless steel to a brazing temperature while maintaining the material in a humidified gaseous atmosphere consisting essentially of a non-reactive carrier gas and a reactive gas present in sufficient concentrations to achieve fluxing; maintaining the surface temperature of the steel for an interval sufficient to permit fusion between the selected metal and the non-ferritic steel surface; after metal fusion has been achieved, allowing the resulting fused metal material to cool to a first lowered temperature in a controlled non-oxidative atmosphere at a rate which retards the formation of fine-grained steel crystals in the metal; and after reaching a metallurgical transformation point, rapidly cooling the fused metal in a controlled atmosphere to a temperature below wh

Abstract: A tunnel for fluxless soldering, is a straight linear tunnel which contains vibrating means to vibrate a solder wave and a non-explosive gas atmosphere. The gas atmosphere includes a small portion of hydrogen or other gaseous reducing agent, sufficient to achieve a fluxing action. A process for soldering an element comprises the steps of conveying the element through a tunnel containing a non-explosive gas atmosphere substantially excluding oxygen, heating the element in the tunnel, soldering the element, and retaining the element in the gas atmosphere of the tunnel until solder on the element has solidified.

Abstract: The fluxless bonding in a reducing atmosphere of integrated circuit contacts containing copper is enhanced using a layer of 200 to 1500 Angstrom thick palladium which inhibits copper oxide formation before fusion and reduces all oxides to promote wetting during fusion.

Abstract: A technique is disclosed for achieving reduced residues on a circuit board (10) following soldering of each conductive member (18) of a component (20) to each corresponding metallized area (12) on the board. At the outset, a layer (22) of low solids solder paste is applied to the metallized areas (12) on the board. Thereafter, an acid is applied to the paste layers (22). Finally, the low solids paste is reflowed while the circuit board (10) is immersed in the inert atmosphere to bond the conductive members (18) of the component (20) to the metallized areas (12) on the circuit board (10).

Abstract: A process is described of preparing composite articles of aluminium or aluminium alloy suitable for superplastic forming by explosion welding two or more components together and heating the welded article to consolidate the bonds. The welds do not extend into areas to which a stop-off composition has been applied and the article can be superplastically formed by passing a pressurized fluid into these stopped-off areas.

Abstract: Inert non-magnetic metals are adhesively bonded to surfaces of metal oxides, for example ferrites, by means of a water vapor-hydrogen atmosphere. Reduction of the metal oxide only takes place at the interface of the inert metal and the metal oxide, after which the metal formed is partly dissolved in the inert metal.

Abstract: An anti-oxidation system of a wire bonder for bonding a wire between a chip pad and a lead frame for a semiconductor device, said wire being comprised of an oxidizable material such as copper or aluminum, wherein a reduction gas for preventing oxidation of the wire is periodically supplied around a spool wound by said wire, at least one gas tube for supplying the reduction gas is disposed towards both sides of a capillary device drawing out the wire, said gas tubes being disposed just beneath the end of capillary device in opposite directions to each other, and a torch being disposed facing with a lower surface of either one of said gas tubes and just beneath the capillary device.

Abstract: A piece of a titanium-base alloy having an elevated temperature phase transformation is diffusion bonded to a second phase at an accelerated rate or reduced temperature, as compared with conventional diffusion bonding, by manipulating the phase transformation with an alloying element that can be readily introduced into, and removed from, the titanium piece. The introduction of hydrogen into the titanium alloy reduces the temperature of the phase transformation. The titanium alloy can be repeatedly cycled through the phase transformation before or during bonding, by the introduction and removal of hydrogen, to reduce the flow stress through transformation plasticity. Alternatively, the titanium alloy may be loaded with hydrogen to reduce the phase transformation temperature, increasing the fraction of the more deformable phase and then reducing the flow stress of the alloy at the diffusion bonding temperature.

Abstract: The present invention concerns a semiconductor device and a process for producing semiconductor device, as well as a wire bonding device used therefor.In accordance with the present invention, a ball formed at the top end of a bonding wire is sphericalized by electric discharge within a reducing gas atmosphere at a high temperature from 100.degree. C. to 200.degree. C. By using the ball of the bonding wire formed under such a condition to the bonding of the bonding pad of a semiconductor pellet, it is possible to conduct highly reliable ball bonding with excellent bondability and with no development of cracks or the like in the semiconductor pellet, as well as to obtain a highly reliable semiconductor device, that is, LSI or IC.

Abstract: A method of soldering without the need for fluxing agents, high temperature, hydrogen, laser excitation or sputtering techniques. The method uses plasma excitation to remove surface oxides from solder surfaces, thereby eliminating the need for post-soldering cleaning in an accurate and efficient manner, resulting in a higher quality and long term reliability solder joint. In addition, serious environmental problems caused by cleaning solvents are avoided.

Abstract: An improved copper radiator for motor cars comprising a plurality of tubes adapted for the flow of a heat-exchanging medium therethrough, fins bonded directly with solder to said tubes to form a copper core and wherein said core is bonded with solder to at least one seat plate, the improvement in that the surface of the fins of said copper radiator has an oxidized layer of a thickness of not more than 1200 .ANG..

Abstract: A process for soldering without using flux and producing a void-free joint comprises the steps of melting the solder in a reducing gas atmosphere such as hydrogen, evacuating the gas to permit the solder joint to expell any trapped gas, then reintroducing the reducing gas and cooling the solder joint. The reducing gas obviates the use of flux to avoid oxidation from interfering with the wetting of the materials to be joined. The materials may be metalized prior to soldering to permit wetting of certain materials such as ceramic.