Abstract: A cover plate extends over at least part of a solder reservoir and has a slot for a solder wave to extend up above the cover plate. Shield gas is supplied under the cover plate to blanket the solder wave and prevent air from contacting the solder wave and circuit boards passing through the solder wave. Circuit boards are generally supported by conveyor fingers at side edges and the fingers pass through the solder wave. End shrouds are provided at both ends of the solder wave to prevent the entry of air through the conveyor fingers and to ensure that the side edges of the circuit board are uniformly blanketed by shield gas directed to the side edges passing up through the slot in the cover plate. The under surface, front edge, back edge and side edges of a circuit board are therefore uniformly blanketed by shield gas as the board passes through a solder wave.

Abstract: A weld root shield device includes an inert gas supply tube having an open end together with a toroidal inert gas supply chamber having orifices therein surrounding the open end of the gas supply tube for replacing air that could be aspirated by inert gas emerging from the open end of the gas supply tube with inert gas emerging from the orifices of the toroidal supply chamber. The shield device is positioned over the weld root being produced by operation of the welding torch, thereby to protect the weld root from oxidation by the atmosphere. The welding torch and the weld root shield device can travel together as an elongated weld is being formed.

Abstract: According to this invention, there is provided a method of manufacturing a highly reliable circuit board in which a copper member is strongly, directly bonded to a substrate made of an aluminum nitride sintered body, thereby obtaining high peel strength. The method of manufacturing the circuit board includes the steps of bringing a copper member containing 100 to 1,000 ppm of oxygen into contact with an oxide layer having a thickness of 0.1 to 5 .mu.m formed on a surface of a substrate made of an aluminum nitride sintered body, and heating the substrate in an inert gas atmosphere containing 1 to 100 ppm of oxygen at a temperature not more than a temperature corresponding to a liquidus including a pure copper melting point of a hypoeutectic region of a two-component phase diagram of Cu-Cu.sub.

Abstract: Potential difficulties with corrosion in heat exchangers utilizing aluminum fins are avoided by using fin and tube constructions made by a method which includes the steps of providing a flattened tube (50) of ferrous material (80) and having an exterior coating (82) predominantly of aluminum; providing at least one serpentine fin (56) of aluminum (86) and clad with a predominantly aluminum braze cladding (88); assembling (102) the fin (56) to the flattened tube (50); applying (94), (100), (104), a brazing flux to at least one of the fin (56) and the tube (50); raising (106) the temperature of the assembly to a level sufficient to at least partially melt the braze cladding (88); and maintaining the temperature for a sufficient period of time to achieve a brazed joint (60) between the fin (56) and the tube (50) but a time insufficient to convert the coating (82) and the cladding (88) to ferrous-aluminum intermetallic compound or intermediate phase.

Abstract: A silicon fusion bonding method and apparatus for bonding silicon substrates in wet oxygen atmosphere. The method comprises a stabilizing step of the silicon substrates, which has been processed in a pre-process, in the wet oxygen atmosphere, a primarily bonding step of the silicon substrates to each other and a heat-treating step of the silicon substrates at a high temperature in the wet oxygen atmosphere in order to remove micro-gaps from a junction interface by virtue of filling-up effect of micro-gaps by interfacial oxide growing.

Abstract: A bonding machine with an oxidation preventive assembly that is made up of two pipes installed on the bonding stage. The two pipes are formed with gas discharge holes and their terminal ends are closed by a block to prevent a back-flow of the gas supplied into the pipes. Thus, a uniform gas atmosphere is created around the workpiece which is placed on the bonding stage, preventing oxidation of the workpiece.

Abstract: The present invention relates to processes and apparatus for welding or joining metal parts which comprise moving a welding torch in a direction along a joint between said parts, causing a molten pool of metal with said welding torch along the joint and directing a laminar flow of inert fluid toward a freshly welded area behind said welding torch in the form of a trailing shield whereby the freshly welded area is protected from the surrounding air during its solidification. The laminar flow or inert fluid may also be directed along the joint ahead of the welding torch in the form of a leading shield such that turbulence in and around the joint caused by a high welding speed is reduced, thereby preventing oxygen entrainment in said molten pool of metal. The laminar flow of inert fluid is usually provided through at least one diffuser having at least one porous diffusing surface which is generally provided with a screen and/or a spatter shield.

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: A cover plate or shroud extends over a solder reservoir and has a slot for a solder wave to extend up above the cover plate. A reduced oxygen atmosphere is supplied from gas outlets under the cover plate on both sides of the solder wave. Furthermore a gas knife is located to direct a stream of gas on an element such as a circuit board as it passes through the solder wave. The cover plate or shroud provides reduced oxides on the solder surfaces and the gas knife removes excess solder on elements that have been solder coated. The apparatus has a solder reservoir for holding solder with a solder nozzle projecting therefrom and a pump for forming a solder wave from the nozzle. Two solder waves may be provided each with their own cover plate and gas supplied on each side of each wave below the cover plate.

Abstract: An component or connector lead (12) is soldered to a bare copper metallized area (14) on a circuit board (16) using core solder (26) by manually applying heat from a heated tip (24) to a separate one of the lead and metallized area. As the heat is being applied, a vacuum is drawn in the region where the solder is applied to the lead and/or metallized area to draw off any flux vapors created upon heating of the solder. At the same time, hot air is also directed into the region where the solder is being applied to maintain the flux vapors, created upon heating of the solder, in their vaporous state to facilitate such vapors being drawn off, thereby reducing the amount of flux residues resulting from the soldering operation.

Abstract: An improved TAB bond is achieved by an apparatus for tape automated bonding, comprising a thermode having a bonding surface. A shield is attached around the bonding surface. The shield is designed so that a nonoxidizing gas may be distributed in a bonding space defined by a plurality of tape leads on a tape positioned below the shield and a bonding area of a semiconductor chip positioned below the tape and the plurality of tape leads. In the bonding position the flow of the nonoxidizing gas removes substantially all of an ambient air in the bonding space.

Abstract: A sliding backpurge device for supplying shielding gas to an arc welding process comprises a concave primary gas chamber surrounded by inner and outer seals which define a pressurized secondary gas chamber therebetween. Pressurized secondary gas is supplied to the secondary gas chamber and primary gas is supplied to the primary chamber. Any leaks which do form, minimize impact on the shield gas within the primary chamber despite sliding engagement of the inner and outer seals over the surface to be welded since secondary gas rather than atmospheric gas leaks into the primary chamber.

Abstract: A solder nozzle to produce a smooth turbulent free solder wave has at least one air jet associated therewith to remove solder icicles and bridges that can form on the under surface of circuit boards and other elements. The circuit boards move in an upward inclined path in the direction of travel and after passing through the solder wave an air knife projects a non-oxidizing gas with sufficient force to remove excess solder. The soldering can occur in a non-oxidizing gas enclosure such as an inert gas, or a reducing gas, and vibrating the solder wave below ultrasonic frequencies can assist in the soldering.

Abstract: A device for hindgas coverage in welding tube pieces (2,3) together comprises two sealing devices (5,6) connected by a rod (7). The sealing devices comprise a first web part (10) with sealing means (8) and a supply duct (11) for hindgas, and a second web part (9) with sealing means (8,25) and discharge ducts (19,20) for controlled outflow of gas to the surroundings. Some of the surfaces of each web part have a two-dimensional curvature (26) for forming the sealing means (8), e.g. rubber discs.

Abstract: A method of precisely depositing accurately defined quantities of solder onto high density circuit patterns on a substrate without use of a solder mask or the like wherein solder paste is originally deposited within a precisely defined transfer member (e.g., graphite block having holes drilled therein), the transfer member then being aligned relative to the respective circuitry such that when both block and substrate are heated, solder flow and deposition will occur without the use of a solder mask or the like. Following deposition, a second circuit member (e.g., flexible circuit) may be electrically coupled to the substrate's conductors, the deposited solder providing the coupling medium. Hydrogen gas may be used during the heating of the paste and also during the soldering of the flexible circuit to the substrate.

Abstract: A cover plate extends over a solder reservoir and has a slot for a solder wave to extend up above the plate, a gas excluding oxygen is supplied under the cover plate and flows up through the slot on both sides of the solder wave to blanket the solder wave. It has been found that oxygen content on the surface of the solder and on the solder wave is reduced so that clean oxide free soldering occurs. The apparatus has a solder reservoir for holding solder with a solder nozzle projecting therefrom, a pump for forming a solder wave from the nozzle, a cover plate for covering at least a portion of the reservoir having a longitudinal slot for the solder wave to pass therethrough. Provision is made for supplying pressurized gas, which is oxygen free, to pass upwards through the slot on both sides of the solder wave to provide a gas blanket over the solder wave, and a conveyor conveys elements to be soldered to pass through the solder wave.

Abstract: A technique for producing a chip mount type package or a TAB package with high reliability, without use of a flux which would cause environmental pollution or would hinder an enhancement of reliability, more particularly pertains to a method of irradiating bonding surfaces, for which a solder is used, and solder bump electrodes of a package with an atomic or ion energy beam, and bonding the bonding surfaces to each other under normal pressure (about 1 atm) in a continuous apparatus.

Abstract: A brazing procedure including the steps of retaining a component (7) having a brazing section (2) therein by means of a die assembly (3, 4) which is compressed by a hot press (8), admitting (6) an inert gas into the component to produce an inert atmosphere inside the component having a pressure which is higher than the outer pressure, and then heating (5) the component thereby brazing the section. A brazing clearance is maintained at a proper amount prior to brazing, and the outer configuration of the component is maintained with enhanced precision. The brazing operation is also advantageous due to its reduced operating cost.

Abstract: According to this invention, there is provided a method of manufacturing a highly reliable circuit board in which a copper member is strongly, directly bonded to a substrate made of an aluminum nitride sintered body, thereby obtaining high peel strength. The method of manufacturing the circuit board includes the steps of bringing a copper member containing 100 to 1,000 ppm of oxygen into contact with an oxide layer having a thickness of 0.1 to 5 .mu.m formed on a surface of a substrate made of an aluminum nitride sintered body, and heating the substrate in an inert gas atmosphere containing 1 to 100 ppm of oxygen at a temperature not more than a temperature corresponding to a liquidus including a pure copper melting point of a hypoeutectic region of a two-component phase diagram of Cu-Cu.sub.

Abstract: In case of suspending an apparatus upon the completion of soldering operation, from not smaller than 50% to less than 95% of a thermomedium in a reflow section is transferred to a filtering tank and the remaining thermomedium is made to pass through a water separator in advance of suspending the apparatus, so that water in the thermomedium is removed. This water removing operation makes it possible to prevent the corrosion of the reflow section and the deterioration of the thermomedium. Additionally, a method is disclosed for preventing water to be mixed with the thermomedium by warming the reflow section before operation.

Abstract: The present invention relates to processes and apparatus for welding or joining metal parts which comprise moving a welding torch in a direction along a joint between said parts, causing a molten pool of metal with said welding torch along the joint and directing a laminar flow of inert fluid toward a freshly welded area behind said welding torch in the form of a trailing shield whereby the freshly welded area is protected from the surrounding air during its solidification. The laminar flow or inert fluid may also be directed along the joint ahead of the welding torch in the form of a leading shield such that turbulence in and around the joint caused by a high welding speed is reduced, thereby preventing oxygen entrainment in said molten pool of metal. The laminar flow of inert fluid is usually provided through at least one diffuser having at least one porous diffusing surface which is generally provided with a screen and/or a spatter shield.

Abstract: A soldering apparatus is disclosed which comprises a conveyor for moving print circuit boards along a predetermined path, an inert gas-filling chamber provided with a solder tank wherein the print circuit board is soldered in the inert gas atmosphere, primary and secondary, external air shutoff chambers positioned in front of and in rear of the inert gas-filling chamber, respectively. Both primary and secondary chambers are provided respectively with a first shutter having a mechanism for open/close action and capable of isolating the inside of the chambers from external air and with a second shutter having a mechanism for open/close action and capable of preventing release of the inert gas in the inert gas-filling chamber and are connected through a valve to a vacuum tank capable of evacuating the primary and secondary chambers.

Abstract: A reflow soldering method and the apparatus thereof is described for soldering a base board having electronic elements located thereon by an inert gas circulated through heater means in a plurality of chambers while the base board is transported through all the chambers, the inert gas being circulated by ventilating means driven by drive means, the method and the apparatus thereof comprising a shield case for enclosing at least the chambers, the ventilating means and the drive means to shut off the same from an outer air and refrigerating means for cooling down the inert gas in the shield case.

Abstract: A fluxless reflow soldering processing and system having a reactive inert gas control arrangement coupled to a conventional reflow soldering head for enabling solder to wet metallic surfaces for joining purposes. The gas control arrangement includes a set of gas regulating valves and heat exchange units for supplying selected quantities of inert gases under pressure at various temperatures to a soldering area during the soldering process. The inert gases are employed to clean the soldering area of metal oxides and are used to facilitate the forming of a reliable solder joint by inhibiting the formation of metal oxides and by helping to cool down the solder joint in a substantially uniform manner.

Abstract: An infrared soldering machine has an inert gas atmosphere to prevent oxidation of the solder. Heaters positioned within the machine housing above a conveyor have through apertures and fans direct inert gas down through the heaters onto the conveyor. The forced convection assists in maintaining uniform temperature across the conveyor. In order to prevent leakage of ambient air into the housing where the fan shafts protrude for connection to electric motors, a gas seal is provided at each fan shaft. The seal extends between two spaced bearings rotatably securing the fan shaft. Each electric motor is mounted away from the heat of the machine and is connected to the respective fan shaft by means of a belt drive. A novel gas curtain, which may be clamped at different angles, improves the gas seal at entry and exit locations of the conveyor.

Abstract: A wave soldering apparatus and process occurs in an atomsphere which substantially excludes oxygen. By providing a gas blanket over the solder, reduction in dross occurs and improved soldering results avoiding the necessity of removing flux residues. Gas diffusers are provided on both sides of a solder wave in an enclosure, the diffusers are placed below the path of the element to be soldered and a further gas diffuser is positioned above the element to be soldered. The gas diffusers supply a calm gas blanket over the solder wave so no turbulent movement of gas occurs within the enclosure.

Abstract: A short hood for enclosing and providing a protective atmosphere over not more than the solder pot of a machine for wave soldering printed circuit boards. Other operative areas of the machine are exposed to air. The entrance and exit openings to the hood for the circuit boards are covered by electrically conductive curtains of thin material cut into vertical strips. The process employs a thin layer of no-clean flux and allows up to 5% oxygen content in the protective atmosphere.

Abstract: A method of forming electrical connections between a flexible film carrier and an electronic device (e.g., semiconductor chip). The method comprises the steps of aligning the film carrier relative to the device having a plurality of solder mounds located on an upper surface thereof. The film carrier is engaged such that bridging portions of conductive leads thereof physically contact these solder mounds. Hot gas is passed through a screen member to heat the bridging portions of the leads to cause these leads to in turn heat the solder mounds to cause the mounds to become molten, whereafter these leads and mounds are cooled to form the desired solder bonds. The resulting structure may form part of an electronic package, this package also described herein.

Abstract: A purge gas unit establishes an enclosed zone for purge gas within tubes or pipes having portions which are to be joined by welding. The purge gas unit includes a first bladder to be positioned on one side of the welding location and a second bladder positioned on the other side of the location. A purge gas supply tube extends through the first bladder and has an opening near the second bladder through which purge gas is supplied to the weld zone or space between the bladders. A vent tube extends through the first bladder and communicates with the weld zone near the first bladder and with a space beyond the first bladder. A safety cable also is attached to the second bladder and extends at least substantially through the first bladder, with the cable enabling the purge unit to be removed from the tubes after welding. The bladders can have annular chambers with central passages through which elongate members can extend. The bladders, in another embodiment, can be substantially flat when not inflated.

Abstract: A tunnel enclosure has a fluid barrier curtain at an entry and an exit and provides an apparatus for soldering an element. The fluid barrier curtains permit an additive, such as a soldering aid or the like to be included with the fluid at the curtain. More than one zone permits different temperatures or gas atmospheres and elements are passed from zone to zone with fluid barrier curtains between. A process for soldering comprises conveying an element into an enclosed zone through an entry containing at least one fluid barrier curtain, with an additive added to fluid in the curtain, heating and soldering the element in the zone, and conveying the element from the enclosed zone through an exit containing at least one fluid barrier curtain.

Abstract: A lineup clamp (10) is disclosed which is particularly suitable for clamping to smaller diameter pipe sections with their ends abutting for welding. Pipes less than twelve inches in diameter can be clamped by the clamp (10). The clamp includes a first resilient element (24) and a second resilient element (28) separated by a separator (26). A hydraulic cylinder (20) is activated to resiliently deform the elements (24, 28) against the separator and the inner surfaces of the abutting pipe sections to clamp the pipe sections in alignment for welding. The clamp is released by removing pressurized hydraulic fluid from the hydraulic cylinder and permitting the resilient elements to rebound to their relaxed configuration.

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: This invention relates to a method of conducting a joining/coating operation which provides good wetting of metal-comprising substrate surfaces by metal-comprising filler/coating materials while reducing the rate of metal oxide formation. The joining/coating operation is carried out in a controlled oxidizing atmosphere having an oxidation capability greater than that required to oxidize a metal-comprising filler material used for joining or a metal-comprising coating, but having less oxidation capability than that of air. Typically the controlled oxidizing atmosphere consists essentially of nitrogen and oxygen, wherein the oxygen concentration is controlled at a set point. The range of the setpoint corresponds with an oxygen concentration which can range from greater than about 10 ppm to about 100,000 ppm, depending on the application.

Abstract: An infrared soldering machine has an inert gas atmosphere to prevent oxidation of the solder. Heaters positioned within the machine housing above a conveyor has through apertures and fans direct inert gas down through the heaters onto the conveyor. The forced convection assists in maintaining uniform temperature across the conveyor. In order to prevent leakage of ambient air into the housing where the fan shafts protrude for connection to electric motors, a gas seal is provided at each fan shaft. The seal extends between two spaced bearings rotatably securing the fan shaft. Each electric motor is mounted away from the heat of the machine and is connected to the respective fan shaft by means of a belt drive.

Abstract: A nozzle assembly is shown for depositing solder onto a series of conductive surfaces such as the mounting pads of a surface mount integrated circuit board. The nozzle assembly includes a nozzle head which has an interior bore for receiving an elongate heat source. The nozzle head also includes an orifice for receiving solid solder fed within the interior bore to contact the elongate heat source. The interior bore terminates in a solder reservoir for molten solder which is fed within the inteiror bore to contact the elongate heat source. The molten solder is dispensed through a tip opening to deposit uniform amounts of solder on each pad. A source of bleed gas is supplied to the interior of the assembly to protect the component parts and excluse oxygen from the interior of the assembly. A cover gas is also supplied to the solder site to reduce oxidation of the moltent solder and reduce the amount of flux required.

Abstract: The present invention is characterized in that, in a ball wedge bonding using a fine bonding wire precoated with a thin insulating layer, ultrasonic vibration is applied to a capillary to effect the delivery of the wire smoothly during movement of the capillary to a second bonding point while delivering the wire after ball bonding at a first bonding point.

Abstract: A method and resulting structure is disclosed in which a metal-to-metal bond is formed by heating the surfaces to be bonded in an oxidizing ambient atmosphere until the desired bond is achieved. Heating takes place at 700.degree. C.-1200.degree. C. and bonding may be enhanced by applying pressure between the surfaces while heating.

Abstract: Disclosed is a method for making a solder joint without flux, in the presence of an inert gas. A pair of articles having solder-coated surfaces are heated to melt the solder, pressure is applied to the joint region, and the articles are cooled. During the heating step, inert gas is flowed over the articles.

Abstract: An method and apparatus for integrally joining at least two composite structures using a bonding material which will melt under heating, with a method comprising the steps of heat-melting the bonding material interposed between the composite structures disposed opposite to each other, changing at least once the pressure of the atmospheric gas surrounding the bonding material in a fused state in a reciprocative manner between an initial pressure and pressure different therefrom, and solidifying the fused bonding material.

Abstract: A method and apparatus for uniting workpieces of silicon-infiltrated silicon carbide with large dimensions includes surrounding each of two silicon-infiltrated silicon carbide workpieces with at least one tightly closing shell in the vicinity of a junction between the workpieces, defining at least one intermediate space between the shell and the workpieces. A vacuum or an inert gas atmosphere is maintained in the intermediate space or spaces. Solder is placed at the junction and the junction is locally heated to soldering temperature for materially bonding the workpieces by soldering at the junction.

Abstract: An apparatus for preventing the oxidation of a lead frame in a bonding system. The apparatus has a first introducing device for introducing a first atmospheric gas toward a bonding portion of the lead frame and a second introducing device for introducing a second atmospheric gas to shield the bonding portion from contact with ambient air simultaneously with the introduction of the first atmospheric gas.

Abstract: Method and apparatus for fluxlessly solder bonding a solder mound to a solder wettable surface. A heated gas, preferably a reducing or non-reactive gas, is directed at a solid solder mound. Gas is heated to a temperature sufficient to melt solder mound. The heated gas is directed at the molten solder mound at a momentum sufficient to disperse an oxide layer at the surface of the molten solder mound. Dispersing the oxide layer permits the molten solder to wet the solder wettable surface. The molten solder is cooled to form a solder bond.

Abstract: Processes and composition for soldering aluminum-containing workpieces wherein the solder contains components which lower the surface tension and the viscosity of the molten solder, and which lower the interfacial tension between the solder and the aluminum-containing workpieces. Useful components are bismuth, strotium, barium and antimony. The solder may be used with or without flux.

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 brazing oven includes an arrangement employing a gas curtain or barrier to cover the port or opening of the oven whenever the door is opened. The curtain or barrier is formed by a region of flowing conditioned air directed across the opening. The flowing air curtain or barrier prevents gas from exiting the oven interior when the door is opened, and it also serves to replace or replenish any conditioned air which happens to escape from the oven interior. The air curtain or barrier is generated by a ported manifold and supply located either on the oven housing exterior adjacent the opening or inside the oven housing adjacent the opening.

Abstract: A workholder having top and bottom frame portions defining a cavity through which a leadframe passes is described. Dew point, moisture, ports are placed in one of the top or bottom frame portions to allow continuous, real time monitoring of the moisture level in the processing environment. A series of clamping an indexing means are integrally disposed within the frame portions of the workholder to clamp and index the leadframes.

Abstract: A method of producing a heat exchanger comprising abutting a tube made of an aluminum material and fins made of an aluminum material, applying to the resulting abutments a flux containing zinc halide, and thereafter conducting a reaction soldering in an inert gas atmosphere. The assembled tube and fins applied with the flux may be moved into a position to enhance the formation if zinc deposited by the reaction soldering during the drying step of the flux. The heat exchanger produced by this method has a thick and uniform Zn coating at the joints with good mechanical strength and surface conditions.

Abstract: A method for joining together a pair of flanged metal pipe sections at their respective flanges. The sections have heat sensitive material juxtaposed to, in contact with or bonded to the interior thereof. The method includes the step of providing coolant passages, each of the passages being located adjacent to respect of one of the flanges in proximity to the heat sensitive material for heat exchange therewith. The flanges are brought into a welding position and coolant is passed through the passages. The flanges are then welded together and coolant is continuously passed through the passages until the resultant welded flanges have cooled. An apparatus for effecting this method is also provided comprising a coolant passage adjacent to the flange and in heat exchange relationship with the flange. The coolant passage has an inlet for introducing coolant and an outlet for exhausting coolant therefrom.

Abstract: An airtight packaging apparatus for covering with a cap a multichip module having LSI chips mounted on a ceramic substrate and for sealing the cap and substrate by means of solder includes a receptacle for accommodating the multichip module, valves for supplying gas to the receptacle and exhausting the receptacle, a retainer for holding the cap and adjusting the positional relation with respect to the multichip module, and a heater for heating solder of the junction between the multichip module and the cap. After solder has been heated and melted, the multichip module and the cap are sealed to each other.