Abstract: A method of diffusion bonding metal or metal alloy containing workpieces, comprises (a) coating the bonding surfaces of the metal or metal alloy containing workpieces with a layer of a coating material, (b) abrading the coated bonding surfaces to remove surface oxide, the coating material being in liquid form, (c) removing excess coating material or excess abraded metal or metal alloy containing workpiece material from the coated bonding surfaces, and (d) diffusion bonding the coated bonding surfaces of the metal or metal alloy containing workpieces together. The coating material is operable to form a stable barrier on the bonding surfaces of the metal or metal alloy containing workpieces under ambient conditions, and evaporates from the bonding surfaces under diffusion bonding conditions. There is also a bonded workpiece formed using the method of diffusion bonding metal or metal alloy containing workpieces.

Abstract: A method of using a solder reflow oven can include disposing at least one substrate including solder in a chamber of the oven. The method can include decreasing a pressure of the chamber to a first pressure between about 0.1-50 Torr. After decreasing the pressure of the chamber, the temperature of the at least one substrate can be increased to a first temperature. Formic acid vapor can be admitted into the chamber above the at least one substrate while nitrogen is discharged into the chamber below the at least one substrate. The method can also include removing at least a portion of the formic acid vapor from the enclosure. After the removing step, the temperature of the at least one substrate can be further increased to a second temperature higher than the first temperature. The at least one substrate can be maintained at the second temperature for a first time. And then, the at least one substrate can be cooled.

Abstract: A method of fusion welding two ferrous alloy component parts, at least one of which is considered unweldable, involves placing a low carbon steel band into a groove defined in part by each of the ferrous alloy component parts and then conveying a concentrated energy source along a welding line that overlaps the low carbon steel band to melt the steel band along with adjacent portions of the ferrous alloy component parts to form a blended alloy weld pool. The blended alloy weld pool solidifies behind the forward movement of the concentrated energy source into a weld joint that fusion welds the ferrous alloy component parts together. The ferrous alloy component parts may include a differential casing and a ring gear. In that regard, a differential casing and ring gear assembly that includes a weld joint is also disclosed.

Abstract: Embodiments of the present technology include clad materials. An example clad material includes a perforated structural substrate, a first ductile substrate roll bonded to the perforated structural substrate in such a way that the first ductile substrate at least partially fills the perforations, and a second ductile substrate roll bonded to the first ductile substrate.

Abstract: A method of making a semiconductor including soldering a conductor to an aluminum metallization is disclosed. In one example, the method includes substituting an aluminum oxide layer on the aluminum metallization by a substitute metal oxide layer or a substitute metal alloy oxide layer. Then, substitute metal oxides in the substitute metal oxide layer or the substitute metal alloy oxide layer are at least partly reduced. The conductor is soldered to the aluminum metallization using a solder material.

Abstract: A water neutralization system that includes a first source of water that is acidic and a second source of water that is basic. A storage reservoir communicates with each of the first source and the second source, and includes a pH sensor that is configured to transmit a signal indicative of a pH of the water stored in the storage reservoir. At least one valve controls fluid communication between the storage reservoir and at least one of the first source and the second source, and a controller communicates with each of the pH sensor and the valve. Based on the signal indicative of the pH of the water stored in the storage reservoir, the controller instructs the valve to adjust an amount of water received from at least one of the first source and the second source to neutralize a pH of the water stored in the storage reservoir.

Abstract: In certain embodiments, a system includes a deposition system and a plasma/bonding system. The deposition system deposits a solder outwardly from a substrate of a number of substrates. The plasma/bonding system comprises a plasma system configured to plasma clean the substrate and a bonding system configured to bond the substrates. The plasma/bonding system at least reduces reoxidation of the solder. In certain embodiments, a method comprises depositing solder outwardly from a substrate, removing metal oxide from the substrate, and depositing a capping layer outwardly from the substrate to at least reduce reoxidation of the solder.

Abstract: A joined body which is formed by, first, an aqueous solution containing an oxide film remover is disposed on a junction region of a first metal plate. Then, with the aqueous solution remaining on the first metal plate, a second metal plate is placed on the first metal plate. Thereafter, a load is applied to junction regions of the first metal plate and the second metal plate in the vertical direction, thereby joining the first metal plate and the second metal plate together to form a junction portion.

Abstract: In certain embodiments, a system includes a deposition system and a plasma/bonding system. The deposition system deposits a solder outwardly from a substrate of a number of substrates. The plasma/bonding system comprises a plasma system configured to plasma clean the substrate and a bonding system configured to bond the substrates. The plasma/bonding system at least reduces reoxidation of the solder. In certain embodiments, a method comprises depositing solder outwardly from a substrate, removing metal oxide from the substrate, and depositing a capping layer outwardly from the substrate to at least reduce reoxidation of the solder.

Abstract: There is provided a flux for soldering and a soldering process which form better solder connection without the occurrence of the poor connection nor the insulation degradation. Such flux which is placed between a solder portion formed on a first electrode and a second electrode when the first electrode is soldered to the second electrode contains: a liquid base material made of a resin component which is dissolved in a solvent, an active component which removes an oxide film, and a metal powder made of a metal of which melting point is higher than that of a solder material which forms the solder portion, and the flux contains the metal powder in an amount in the range between 1% and 9% by volume based on a volume of the flux.

Abstract: After a microcrystalline layer having a grain size that is finer than that of a base member is formed on the surface of at least one of a first bonding portion and a second bonding portion, the gap between the first bonding portion and the second bonding portion is filled with a solution into which copper oxide can be eluted, so as to deposit copper oxide contained in the surface oxide film into the solution. By applying pressure and by heating at a temperature of at most the copper recrystallization temperature, the components contained in the solution are removed except for copper, so as to elute copper oxide, thereby bonding the first bonding portion and the second bonding portion via the copper thus deposited. Subsequently, the copper is solid-phase diffused into the first bonding portion and the second bonding portion.

Abstract: A brazing sheet for flux-free brazing, comprising a core material, a brazing material disposed on at least one surface of the core material, and a thin skin material disposed on the brazing material, wherein the core material is made of an aluminum alloy having a higher melting point than that of the brazing material; the brazing material is made of an Al—Si—Mg based alloy and has a thickness of 25 to 250 ?m; the thin skin material is made of an aluminum alloy having a higher melting initiation temperature than the brazing material and containing substantially no Mg, and has a thickness of 5 to 30 ?m; and a content of an oxide existing at an interface between the brazing material and the thin skin material is 0.1 ppm or less in weight ratio with respect to the entire clad material. The present invention provides a brazing sheet for flux-free brazing, which has a thin skin material, with uniform brazing characteristics, and enables stable joining.

Abstract: Methods of forming bi-metallic castings are provided. In one method, a metal preform of a desired base shape is provided defining a substrate surface. A natural oxide layer is removed from the substrate surface, yielding a cleaned metal preform. The method includes forming a thin metallic film on at least a portion of the substrate surface of the cleaned metal preform, and metallurgically bonding the portion of the metal preform having the metallic film with an overcast metal to form a bi-metallic casting. The metallic film promotes a metallurgical bond between the metal preform and the overcast metal. In one aspect, the metal preform may comprise aluminum (Al) and the metallic film may comprise zinc (Zn).

Abstract: A method includes performing a plasma activation on a surface of a first package component, removing oxide regions from surfaces of metal pads of the first package component, and performing a pre-bonding to bond the first package component to a second package component.

Abstract: The gap between first and second bonding portions is filled with a disperse solution obtained by dispersing copper micro-particles into a solution for copper oxide elution, so as to elute copper oxide configured as the outermost layer of the first bonding portion and copper oxide configured as the outermost layer of the second bonding portion, and copper oxide formed on the surface of each copper micro-particle. Pressure is applied to the first and second bonding portions using a press machine so as to raise the pressure of the disperse solution. At the same time, heat is applied under a relatively low temperature condition of 200° C. to 300° C., so as to remove the components contained in the disperse solution except for copper, thereby depositing copper. Thus, a first base portion and a second base portion are bonded via a copper bonded portion containing copper derived from the copper micro-particles.

Abstract: The invention relates to a method for joining ceramic composite parts comprising at least one ceramic material and at least one superhard material to at least one other part, the method comprising treatment of a joining surface or surfaces of the ceramic composite part; and disposition onto the treated surface or surfaces, or portions thereof, of a material capable of bonding to the ceramic composite part as well as to the at least one other part upon the application of sufficient heat. The invention extends to articles comprising a ceramic composite part comprising ceramic material and at least one superhard material, bonded to at least one other part, the article including at least one layer selected from an attachment layer, a brazeable layer, and an oxidation resistant (braze compatible) layer or combinations thereof included at an interface between the ceramic composite part and the other part.

Abstract: A method of removing oxidation from certain metallic contact surfaces utilizing a combination of relatively simple and inexpensive off-the-shelf equipment and specific chemistry. The method being a very rapid dry process which does not require a vacuum or containment chamber, or toxic gasses/chemicals, and does not damage sensitive electronic circuits or components. Additionally, the process creates a passivation layer on the surface of the metallic contact which inhibits further oxidation while allowing rapid and complete bonding, even many hours after surface treatment, without having to remove the passivation layer. The process utilizes a room-ambient plasma applicator with hydrogen, nitrogen, and inert gasses.

Abstract: First, an aqueous solution (103) containing an oxide film remover is disposed on a junction region of a first metal plate (101). Then, with the aqueous solution (103) remaining on the first metal plate (101), a second metal plate (102) is placed on the first metal plate (101). Thereafter, a load is applied to junction regions of the first metal plate (101) and the second metal plate (102) in the vertical direction, thereby joining the first metal plate (101) and the second metal plate (102) together to form a junction portion (110). In this manner, a joined body is manufactured.

Abstract: An electrode bonding method according to the present invention includes: a plasma cleaning step of irradiating an electrode surface to be cleaned of at least either one of a part, such as a semiconductor device, and a substrate with atmospheric pressure plasma for cleaning; an inert gas atmosphere maintaining step of covering the electrode surface to be cleaned and its vicinity with a first inert gas before the irradiation of the atmospheric pressure plasma is ended, and maintaining that state even thereafter; and a bonding step of bonding an electrode of the part and an electrode on the substrate before the inert gas atmosphere maintaining step is ended. The electrode surface is thereby plasma-cleaned without the possibility of damaging the part to be bonded to the substrate, and the cleaned state is maintained while bonding the electrodes to provide an electrode bonding state of high bonding force and high reliability.

Abstract: A method for bonding two partially form-fitting surfaces of two metal bodies which contain the same metal is carried out by generating a first layer on the surface of a first one of the two bodies, the first layer containing a mixture of the metal and the oxide of the metal; generating a second layer on the first layer, the second layer containing the metal but less oxide of the metal than does the first layer; placing the partially form-fitting surfaces of the two metal bodies adjacent to each other; heating the bodies placed adjacent to each other to a temperature which lies in a target range below the melting point of the metal and above the eutectic temperature of the eutectic of the metal and the metal oxide; and holding the temperature within the target range over a predetermined or a controllable duration of time.

Abstract: A method of a semiconductor package includes providing a substrate having a conductive trace coated with an organic solderability preservative (OSP) layer, removing the OSP layer from the conductive trace, and then coupling a chip to the substrate to form a semiconductor package.

Abstract: A Sn—Ag bonding and a method thereof are revealed. By means of a bonding layer formed by tin and silver between wafers, the stress released by diffusion and bonding between tin(Sn) and silver(Ag) is larger than the stress released by diffusion and bonding of conventional gold-silver bonding. Moreover, a Sn—Ag bonding method of the present invention forms Sn—Ag bonding at low temperature and releases more stress so as to reduce thermal stress generated during wafer bonding effectively. And after wafer bonding, the high temperature processes can be performed.

Abstract: A method for repairing a gas turbine engine component includes applying a braze slurry to a first portion of the component, applying a pre-sintered preform to a second portion of the component that is different than the first portion, and brazing the component.

Abstract: A Sn—Ag bonding and a method thereof are revealed. By means of a bonding layer formed by tin and silver between wafers, the stress released by diffusion and bonding between tin(Sn) and silver(Ag) is larger than the stress released by diffusion and bonding of conventional gold-silver bonding. Moreover, a Sn—Ag bonding method of the present invention forms Sn—Ag bonding at low temperature and releases more stress so as to reduce thermal stress generated during wafer bonding effectively. And after wafer bonding, the high temperature processes can be performed.

Abstract: The present invention provides a method of joining a metal that can join coppers at a relatively low temperature by a simple technique while maintaining connection reliability. The space between a first coating portion (14) (a copper oxide) coating a first base portion (12) (copper) and a second coating portion (24) (a copper oxide) coating a second base portion (22) (copper) is filled with a solution (30) in which the copper oxide of the first coating portion (14) and the copper oxide of the second coating portion (24) are to be eluted. As a result, the copper oxides forming the first coating portion (14) and the second coating portion (24) are eluted in the solution (30). To increase the pressure of the solution (30), pressure is applied to a first to-be-joined portion (10) and a second to-be-joined portion (20) with a pressing machine. During the pressure application, heating is performed at a relatively low temperature of 200 to 300° C.

Abstract: Described here is a method for pretreating the surfaces of weld parts of aluminum or alloys thereof, and weld parts produced with said method. Prior to welding, the weld parts are subjected to a treatment (17) in an acidic, aqueous solution, wherein the acidic, aqueous solution contains ions of the elements boron and/or silicon and/or titanium and/or zirconium and/or hafnium. The invention consists in that a polishing step (9) is carried out prior to the treatment in the acidic, aqueous solution to make for better sliding in a feed apparatus during the welding process.

Abstract: A method of removing oxidation from certain metallic contact surfaces utilizing a combination of relatively simple and inexpensive off-the-shelf equipment and specific chemistry. The method being a very rapid dry process which does not require a vacuum or containment chamber, or toxic gasses/chemicals, and does not damage sensitive electronic circuits or components. Additionally, the process creates a passivation layer on the surface of the metallic contact which inhibits further oxidation while allowing rapid and complete bonding, even many hours after surface treatment, without having to remove the passivation layer. The process utilizes a room-ambient plasma applicator with hydrogen, nitrogen, and inert gasses.

Abstract: It is an object to provide a water-soluble preflux containing a low-volatile solubilizing agent excellent in performance to dissolve an imidazole compound in water and capable of bringing out an excellent film-forming property of the imidazole compound and also to provide a treating method for the surface of a metal conductive part which comprises bringing the surface into contact with the above water-soluble preflux.

Abstract: A laminate aluminum block for forming an article includes a series of aluminum laminate plates to collectively form a tool body for forming an article in a forming operation. A series of aluminum brazing layers are formed for brazing together adjacent aluminum laminate plates. The series of aluminum laminate plates and the series of aluminum brazing layers are deoxidized. Draining apertures are formed through a plurality of the series of aluminum laminate plates. The series of aluminum laminate plates are stacked alternating with the aluminum brazing layers between adjacent aluminum laminate plates without a flux. The stacked series of alternating aluminum plates and aluminum brazing layers are pressed. The stacked series of alternating aluminum plates and aluminum brazing layers are heated in a vacuum furnace to a temperature wherein the aluminum brazing layers braze the aluminum laminate plates together and excess braze material drains from the draining apertures.

Abstract: A method for joining microstructured component layers and a method for manufacturing microstructure component layers and the microstructure component layer is provided. At least one multifunctional barrier coating is applied to the joining surfaces of a base material layer for the microstructured component layers. The layers are made of aluminum/aluminum alloys and/or copper/copper alloys, and/or noble steels. At least one solder/brazing coating is applied to each barrier coating. The coated base material layers comprising the component layers are stacked. The stacked component layers are joined by solder/brazing using heat. The melting temperature of the solder/brazing coating is higher after the heat joining than before same.

Abstract: There is provided a method for producing a metal/ceramic bonding circuit board, which can form a fine pattern even if a circuit forming metal plate is thick and which can shorten the time required to carry out etching, when a molten metal is caused to contact to a ceramic substrate to be cooled and solidified to bond the circuit forming metal plate to the ceramic substrate to etch the circuit forming metal plate to form a metal circuit plate having a desired circuit pattern. A molten metal is caused to contact both sides of a ceramic substrate 10 to be cooled and solidified. Thus, a circuit forming metal plate 12 having a shape similar to a desired circuit pattern is bonded to one side of the ceramic substrate 10, and a metal base plate 14 is bonded to the other side thereof.

Abstract: A low-temperature flux is described which dissolves the refractory oxide layer from a shape memory alloy containing both nickel and titanium, such as Nitinol, and from other metals like stainless steel. The flux is particularly useful for preparing shape memory alloy members for soldering and permits joining of such members to other members, comprising, for example, stainless steel, used in structures like medical devices. The flux is a non-aqueous molten salt formulated on eutectic mixtures of KOH (potassium hydroxide), NaOH (sodium hydroxide) and LiOH (lithium hydroxide), with melting temperatures in a range from about 170° C. to about 226° C.

Abstract: A method for assembling chips onto substrates includes applying a flux-free, no-flow underfill material. In an embodiment, the method includes removing oxide from interconnects without the use of a flux and applying a flux-free, no-flow underfill. In an embodiment, the method includes removing oxide from bumps, applying no-flow underfill to a substrate, and fluxlessly connecting the bumps to pads on the substrate. In an embodiment, oxide is removed from the bumps by a plasma treatment. In an embodiment, oxide is removed from the bumps by a subjecting the bumps to an oxide reduction process. The assembly of the chips and substrate is free from flux residue and/or flux cleaning solution residue.

Abstract: A method for manufacturing a printed circuit board includes: washing a land that corresponds to the exposed portion of a copper circuit of a printed circuit board with acidic electrolytic water having a pH of not more than 5 to remove an oxide; treating the land with basic electrolytic water having a pH of not less than 9 to prevent oxidation; and soldering electronic components to the land. The portion to be soldered is treated with the electrolytic water beforehand, thereby improving soldering at low cost without any adverse effect on the environment.

Abstract: A process including providing a semiconductor device including a bond pad, and an under bump metallurgy overlying the bond pad. Forming a solder structure over the under bump metallurgy, and wherein the solder structure includes an outer layer including tin oxide. Producing a plasma from at least one of CF4, SF4, and H2 and exposing the solder structure to the plasma. Heating the solder structure and cooling the same to provide a solder bump on the semiconductor device.

Abstract: There is provided a chamber open to the outside through openings through which a solder-adhered object is passed and the chamber having a heating/melting area, a carrying mechanism for carrying the solder-adhered object into the heating/melting area, a formic-acid supplying means for supplying a formic acid into the heating/melting area, an exhausting means for exhausting a gas from the heating/melting area and its neighboring area to create a lower pressure area in the heating/melting area as compared to the pressure of outside the chamber, heating means for heating directly or indirectly the solder-adhered object in the heating/melting area, and an air-stream suppressing means for disturbing a gas flow between the heating/melting area and the carrying areas.

Abstract: A method for manufacturing a printed circuit board includes: washing a land that corresponds to the exposed portion of a copper circuit of a printed circuit board with acidic electrolytic water having a pH of not more than 5 to remove an oxide; treating the land with basic electrolytic water having a pH of not less than 9 to prevent oxidation; and soldering electronic components to the land. The portion to be soldered is treated with the electrolytic water beforehand, thereby improving soldering at low cost without any adverse effect on the environment.

Abstract: An effective method for cleaning flux residues produced in process of fabricating semiconductor devices, and a method of fabricating the semiconductor devices including this cleaning method are provided. The flux cleaning method for cleaning the solder bump electrodes formed using a flux comprises the steps of: applying a pretreatment process including coating of the solder bump electrode with the flux and applying a heat treatment thereto, and carrying out the flux cleaning to clean the heat-treated flux.

Abstract: The invention provides a water-soluble preflux that can solve problems with a soldering land array having a narrow spacing in that fused solder is likely to cause soldering bridges with defective soldering, a printed circuit board with its film formed thereon, and a surface treatment process for a metal in that circuit. The water-soluble preflux comprises given two different benzimidazoles compound and an iodine-based compound optionally with an amino acid, etc. The invention provides a printed circuit board with a film of that preflux formed thereon, and a surface treatment process for the metal in that circuit.

Abstract: A composition and method for cleaning and conditioning a non-conductive surface defined by a through hole in a printed circuit board (PCB) is disclosed. The through hole surface is contacted with the composition of the invention to provide a cleaned and conditioned surface. The clean and conditioned surface is coated with conductive carbon particles (usually graphite) to provide a carbon-coated surface. The carbon-coated surface is electro plated and then soldered using hot solder. Those surfaces that have been soldered and also treated with the composition of the invention exhibit fewer blow hole problems. The composition of the invention comprises carbonates, binders, and resins, and combinations thereof, that improve the adhesion and coverage of a coating containing graphite to a surface defined by a through hole bore or other substrate. (“Through holes” as used herein refers both to through holes and to vias.

Abstract: There is provided a semiconductor device manufacturing method which comprising the steps of forming solder bumps on an underlying metal film of a semiconductor device, and placing the semiconductor device and the solder layer in a reduced pressure atmosphere containing a formic acid to heat the solder bumps. Accordingly, the solder bumps can be formed without the use of flux not to generate voids in the solder layer, and also the cleaning required after the solder bumps are formed can be omitted.

Abstract: By utilizing a roll bonding process and appropriately forming steps, a load bearing structure is created which is capable of handling and appropriately transferring loads. One preferred method includes the combination of roll bonding and hydroforming to efficiently create structural components. While various product configurations are possible, one version includes a waffle-type structure produced by appropriate roll bonding of material sheets. This waffle-type structure can also undergo additional forming steps to create several structural components capable of handling and carrying loads in a very efficient and effective manner. More significantly, this process enables the use of structural aluminum for load bearing components which are efficiently and cost effective when manufactured.

Abstract: The present invention relates to a method for producing a tin-silver alloy plating film having an excellent wettability and improved in solderability and said method comprises a step of heat treating the surface of the tin-silver alloy plating film preferably the heat treating temperature is 70-210° C.

Abstract: An integrated solder bump deposition method and apparatus that enables solder bumps to be lithographically formed on a substrate. The apparatus comprises a plurality of electrolyte cells, and etch/clean/passthrough station and a reflow chamber.

Abstract: A method of manufacturing a hermetically sealed chamber, including preparing two aluminum or aluminum alloy material members which face each other, forming a first extending convex portion on a surface to be metal-bonded of one of the two aluminum or aluminum alloy material members, where the first convex portion extends in a manner to make an enclosure, forming a second extending convex portion on a surface to be metal-bonded of the other of the two aluminum or aluminum alloy material members, where the second convex portion extends in a manner to make a corresponding enclosure, and receiving internally packaged parts therebetween, fitting the first extending convex portion and the second extending convex portion, and causing the first extending convex portion and the second extending convex portion to be metal-bonded by press-forging.

Abstract: After copper plates 14 are bonded to both sides of a ceramic substrate 10 via a brazing filler metal 12, UV curing alkali peeling type resists 16 are applied on predetermined portions of the surfaces of the copper plates 14 to etch undesired portions of the copper plates 14 to form a metal circuit portion. While the resists 16 are maintained, undesired portions of the brazing filler metal 12 and a reaction product, which is produced by a reaction of the brazing filler metal 12 with the ceramic substrate 10, are removed (or undesired portions of the brazing filler metal 12 and a reaction product, which is produced by a reaction of the brazing filler metal 12 with the ceramic substrate 10, are removed, and the side portion of the metal circuit portion is etched). Thereafter, the resists 16 are peeled off, and an Ni—P electroless plating 18 is carried out.

Abstract: Residue contaminates semiconductor devices during processing in a furnace. Residue contamination is prevented by removing the residue before it builds up to a point where it can contaminate semiconductor devices. Residue build-up is monitored using a residue build-up monitoring device mounted on the furnace exhaust stack. When residue build-up reaches a predetermined level a signal is generated by the residue build-up monitoring device notifying technicians that furnace cleaning is required.

Abstract: A method of cleaning residue on surfaces in a reflow furnace includes introducing a solvent into the furnace chamber; reacting the solvent with the residue to form a product; and, removing the product from the furnace chamber. The solvent is gaseous, such as an etch gas. Also, the product of the reaction between the residue and the solvent can is gaseous. The gaseous product can then be exhausted from the reflow furnace. A reflow furnace for practicing the method is also disclosed.

Abstract: A method of joining superalloy substrates together comprises diffusion bonding the superalloy substrates by depositing an activator directly on the surface of the joint to be bonded and thereafter subjecting the joint to heat and pressure. The heat and pressure causes the surface of the superalloy, in the presence of the activator, to diffusion bond without the use of a brazing alloy. By eliminating the brazing alloy, a high strength, high temperature bond is achieved, yet there is no molten brazing alloy to be drawn through capillary action into any fine features surrounding the joint being bonded, and there is no residue left at the interface that would diminish the mechanical properties of the joint.

Abstract: There are provided a chamber having openings which are opened to an outer air and through which a solder-adhered object w is passed and having a heating/melting area and carrying areas arranged adjacent to the heating/melting area, a carrying mechanism for carrying the solder-adhered object w into the heating/melting area, a formic-acid supplying means for supplying a formic acid into the heating/melting area, an exhausting means for exhausting a gas from the heating/melting area and its neighboring area to lower a pressure in the heating/melting area rather than an outer air, heating means for heating directly or indirectly the solder-adhered object w in the heating/melting area, and air-stream suppressing means for disturbing a gas flow between the heating/melting area and the carrying areas.