JPS62501546A - Soldering equipment and method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a soldering apparatus and method, whereby any solder-containing As a result, the assembly was subjected to both steam heat treatment and ultrasonic vibration at the same time. Therefore, soldering without 7lux (a substance applied to the joint) is realized. like this The method and equipment are used clinically in preparation for soldering and solder flux application. This is particularly useful for assemblies that are sensitive to engineering operations.

A typical printed circuit board has a circuit network formed on one surface and an individual circuit on the opposite surface. Separate parts are provided. The leads on these discrete components are An opening passes through the plate and extends onto the cylinder circuit side. Here, pudding Solder the top board to complete the circuit network described above. Clean this board and This printed circuit side is brought into contact with impurity-free solder. Handa U So that a surface free of impurities can be obtained by sold@r wave Become. The melted solder wets the printed circuit and leads for high reliability. soldering will be performed. This type of solder allows for wettable surfaces. Another option is to use a molten ultrasonic solder pot. Ie 5older pot).

In this case, the ultrasonic energy will remove the moisture from the printed circuit and leads. oxides, fluxes and impurities. Since pure substances can be removed, highly reliable semi-containing work can be achieved. b Misalignment place Even if solder is used, the flux maintains a wettable surface until direct solder It is necessary for the purpose of This type of soldering system is designed to apply solder to the connected parts. These connection parts are useful for adding solder from the pot. It is something that is prepared.

In vapor phase soldering, the assembly containing the solder can be soldered in this vapor at a temperature of This refers to a system that heats up to This vapor creates an inert gas (1 Atmosphere) is obtained and the 5 assemblies are soldered. Heat is obtained to raise the temperature. Such vapor phase soldering (vapor p hase sotderffing) (i.

Solder is already present in the assembly and flows back into the joint due to heating It is effective under such circumstances. This type of soldering is accomplished in a furnace. By using an inert gas in this furnace, highly reliable solder connections can be made. It helps to be realized. However, when rejoining the surfaces by soldering, 6 , wash this 1.7. Must be free of oxide flux and impurities. p, this is the soldering required for high reliability soldering at certain temperatures. It is.

According to current soldering/stem systems, cleaning and fluxing operations can be harmful. High reliability of assemblies containing sensitive devices) Soldering A hole where you can't accomplish your karma. Such devices include semiconductor chips and thin films. Contains circuitry. Therefore, components containing such semiconductor devices Soldering is a device that can be used to contact and/or electrically connect a and methods were required.

Summary of the invention In order to better understand the present invention, the soldering apparatus and method of the present invention include: An assembly with solder between two parts of the assembly, melting the solder At the same time, these two are exposed to an inert gas at a temperature high enough to The solder bond is bonded between these parts by applying vibrations that cause relative movement between the parts. This feature is characterized by the fact that the

Therefore, one purpose and benefit of the present invention is to provide an apparatus and method for soldering as follows. It is to provide. That is, in this device, one of the two parts is soldered using normal solder. Responsive to and protected from joint cleaning and fluxing operations. This ensures that reliable soldering and bonding are achieved.

According to another object of the invention, a high temperature inert gas contained in a vessel is This is achieved by heating the assembly with a vibration source and a high frequency vibration source. The solder joint receives heat and vibration at the same time to ensure proper solder bonding. It is to provide an apparatus and method for such soldering.

Another object of the present invention is to solve the problem of assemblies to be soldered by reflowing solder. By floating the solder on a fluid solder pot and making the fluid solder vibrate at high frequency, The assembly is exposed to high temperature inert heat while applying vibration to the assembly. This inert gas dissolves the re-entering solder in the assembly. To provide a soldering apparatus and method characterized by a sufficiently high temperature. It is.

Other objects and benefits of the invention arise from the following portions of the specification, claims and appendix: This will become clear by referring to the drawings.

FIG. 1 is a vertical mid-section view of the soldering device according to the invention, including the cover and cooling The tile and solder pot are shown in an enlarged side view.

FIG. 2 is a perspective view of an assembly to be soldered with the apparatus and method of the present invention; Partially broken.

explanation The soldering apparatus of the present invention in combination with the soldering method of the present invention is generally illustrated in FIG. It is displayed as 10. This device is equipped with a pace 12, which A soldering pot (hereinafter abbreviated as pot) 14 is supported by a base 12 of . This pot 14 contains solder 16, which is applied near the edge of the pot. This is shown in a broken diagram. Heat the solder 16 so that it becomes a liquid (fluid). The heater coil 18 is used for heating I-. This coil 18 is designed to encompass the pot 14. It is installed in A heater power supply 20 supplies heater power. This h- - Feedback is provided to the evening power supply to control the heater power, The solder 16 is maintained at a preselected temperature.

An electromechanical transducer 22 is secured to this pot. Transducer 2 2 is supplied with power from a power supply 24, and this power supply 24 converts high frequency power into a transducer. - is applied to the sensor 22. This frequency should be ultrasonic or a frequency close to it. It's a good thing. Transdazer 22 is mechanically coupled to solder pot 14 and electrically connected. When energized by the source 24, the transducer 22 generates high frequency vibrations such as ultrasonic vibrations. Waves are now supplied to the solder 16.

A support plate 24 is placed on the pace 12 and an opening is formed therein. During this opening A solder pot 14 is attached to the. The wall 26 is provided with a vessel wall. In contrast, the support plate 24 and the solder i3? Butt 14 is the bottom. ing. As shown in Figure 1, the overall structure is: Although it has a square or rectangular shape, it has a circular cylindrical shape with respect to the vertical axis. this The wall 26 is a double wall.

These double walls include an inner skin 28, an outer skin 30, and thermal insulation therebetween. 32 are provided. The vessel 34 defined in this way is covered by the cover 36. and enclosing the inner space 38.

The cover 36 can be moved to access this interior space.

A cooling coil 4Q is installed around the inside of the upper part of this vessel. This coil 40 is provided with a fluid inlet 42 and a fluid outlet 44, which allow the vessel to A cooling seam can be formed in the upper part of the module. By using this cooling coil, Therefore, the steam produced in the space 38 is condensed and used in the vessel when the device is used. Steam can be prevented from disappearing from the top. The fluid used in this cooling coil is It is related to the evaporation point of the heating fluid used within the interior space. Follow this example For example, proper condensation of this vapor can cause room-temperature water to be mixed with the evaporated material in the cooling coil. This is achieved when used as a fluid. The material within the inner space 38 is at operating temperature. It is in a steam state at 1 h. This preferred material is a large molecule halogenated organic material. and this material is Driftwood FC available from 3M Company of St. Paul, Minnesota. It is 70. This cooling material evaporates at 215°C and is inert with respect to solder line separation. Additionally, soldering is inert for most assemblies with possible joints. It is. This fluid, which has a vaporization point of 215°C, is the preferred material and most It is compatible with most solders. Multi-step soldering requires work If so, there is Fe12 available from the same 3M company, and this fluid is 25 It has a vaporization point of 3°C.

Intermediate temperatures can be obtained by mixing these two fluids in appropriate proportions. It becomes like this.

In order to better understand how to use the device of the present invention, please refer to the device and method of the present invention. An example of an assembly to be soldered is thus shown in FIG. This assembly 50 is provided with a Vj:5 chip 52. This chip includes a plurality of halves. A conductive electronic device is provided.

The chip 52 is mounted on the chip carrier 54 using epoxy. 4 is a ceramic support for supporting the chip, J? −). This chip 52 Before fixing, the chip carrier 54 is subjected to silk screen processing and etching processing. or have leads plated on top of it. These leads are The edge of the top carrier 'From the bottom of this to the bottom of this'! , <E, : &-t- It's gummy. This bottom coat is so long! L lead each semicircle U It can be moistened with water. Connect the pads on the chip to the chip carrier/? Rudd, If the lead wire is connected to the throat, e.g. lead 58" (lead wire connected to the throat) A five-wire connection such as ear 60 is used.

Support, fixation, and connection between these chip carriers and these leads are issues. Ru. Assembly 5θK i, 1 board 62 is provided, this is also a talent / secret It is lamic. On top of this board 620 several leads and pads are silked. Screened. Lee Dro 4.66 is particularly useful for multiple such leads. It is in the north expressed as de. Leads 68 and 70, chip carrier 54 and others between the chip carrier and/or mounted on the substrate 62, screen printed, or printed. plated or etched to connect between the first and second vices. is displayed. The lead on the board (71, the edge size of the Chinni f gear rear 54) 7) Chip carrier with the end of 6 leads 72 indicated by a broken line. The edges of the top of the substrate 62 are shown (r and r); Silk-screened in the correct position: “C is or is it?”: other conventional provided by the method.

In addition to these leads and noses, there are multiple attachment squares. Silk screen on the top surface of plate 62. The positions of these squares are It acts as a contact point (:7 contact point) and also acts as a contact point under the chip carrier 54. It is located on the side. 74.76 for two of these contact points Display in . These points are at a distance j- from the leads mentioned above. These points When the chip carrier is brought into contact with the top surface of the substrate? let me understand It is used to connect not only the physical connection of the chip carrier to the substrate, but also the A good thermal path between the elements is created. In Figure 2, multiple small A small contact point was provided, but a larger contact point can be added if desired. It is also possible to provide a small number of ports.

The method and apparatus of the present invention provides a semicircuit for attaching a chip carrier 54 to a substrate 62. It is particularly suitable for use in implementing steps. chip carrier 54 to be soldered to the substrate 62, such as the edge of the chip carrier 54. Thermal conduction area of the lead immediately below and /″!, Take contact point 74.7 6 is provided with a controlled amount of solder, and this solder is applied to the chip carrier 5. These areas are allowed to flow and wet prior to the introduction of 4. Cooling the cooling fluid Let's pass through 40, energize heater 80, and then turn on the inert body. Materials (inert at, ornoiphr + romaterial) in the space This inert material is heated by a semi-FJ3 tank 16. ? - of +] fee 1.・”, is a fluid at room temperature and 1. Heat to evaporate The temperature of the glue is sufficient to melt the half-H. Generated in a blank internal space. This steam t! 1 Air is heavy, so this bed It remains in the cell.

However, in order to prevent this vapor from disappearing, a cooling coil 4θ is used. condenses the upper layer of vapor, which lowers the internal walls of the vessel and returns to It starts to come. Since the power supply 24 is energized, the solder bath 16 is vibrated at high frequency. can be done.

The solder melts and the melting of the inert gas material takes place at a temperature that is at least half Once the appropriate temperature is reached, the assembly 50 of FIG. 2 is delivered. This app Assembly 50 includes a chip carrier 54 disposed on top of substrate 62. It is. This assembly IJ 50 can be cleaned and treated with a fluxing agent. ? : The reason is that the semiconductor chip 52 exists and the flux 54 and the substrate 62. If it cannot be completely removed A problem will arise. Use this assembly as a clamp, template, or other Holding with a positioning device, remove cover 11 36 and then remove this assembly. Guri, lower the IC inside Vessel, and go. This assembly virtually eliminates soldering. in the vapor zone for a long enough time to melt target 1. It will be left behind. This assembly 501'j, a half subjected to high frequency vibration. Floating above the field 16. This vibration cleans the surface, causing flash A solder surface free of impurities can be obtained by using a solder surface without any adhesive, and these can be bonded reliably. It is something that This bonding includes fixing the chip carrier 54 to the substrate 62. It is. This includes contact points 74 and 76. Fix by dissolving the semi-IF in a 4-step process. These contact points The solder is in contact with the lower surface of the ceramic chip gear rear 54, and Therefore, the chip zo carrier is fixed in the correct position and the heat from the chip 52 is removed. A conductive path is formed within the substrate 62. Furthermore, each of these leads 56.58 i. Contact leads 64 and 66 to connect the pads on the chip carrier to the nozzles on the substrate. An electrical connection to the rad is made. In this way, from the chip carrier to the board All electrical connections are made by soldering Δ to the edges. Become so.

The important point here is that the vapor in the space 38 is an inert gaseous material and the solder It provides the basic heat for melting. Half l'-B tank 16 heat is supplied to this inert gas supply. As the assembly 5θ is allowed to float (becomes C and in this case Clash between Jinsu r5,-,,-9-22 and assembly 50! Secure the ring can stand. -), there is no need to use special solder for this tank 1σ, Any fluid having an operating temperature of 20°C to 40°C may be used. The temperature of this fluid is the boiling point of the fluid. + from the boiling point, which causes it to boil so that steam for heating is produced; Furthermore, it is necessary that the assembly C has a higher density than the assembly 5o. For this reason, this The assembly retains heat and an inert abrasive material while being subjected to mechanical vibration. However, it can float on top of this fluid. According to the above-mentioned base/group zone. [The assembly that should not be soldered can be heated in advance, and this assembly f IJ can be heated in advance. It is heated while it is present in the space in the cell at the top of the layer. 'Ma Additionally, this zone preserves inert material3, which prevents impurities from forming in the solder. is prevented from occurring. Furthermore, heat is added by this steam, so the actual 11 (d temperature is achieved by vapor condensation and ultrasonic energy Since the flux is applied to the assembly at temperature, this results in no flux. Highly reliable soldering can be achieved.

Although only the best mode of the invention has been described, it is understood that various other modifications can be devised. Easy for those skilled in the art.

Procedure Ne City I ni’i! ,,F (to the right)1. Display of incidents PCT/'US85102308 2. Name of the invention Soldering equipment and its H method 3. Person who makes corrections Relationship to the incident: Patent applicant Name: Hughes Aircraft Company 4, Agent 248, UBE Building, 3-chome, 7-2 Kasumigaseki, Yen-ku, Tokyo, March 1988 ( "Date of shipment) international search report ANhlEXTTo’I’HEINTERNATIONALSEARCHREPO R-cho) NUS-A-431504209102, /B2 NO1 DE-8- 1591829('+47'03/7'L NoneUS-A-36749'7 5 04107 / 'l' 2 N o r + a

Claims (15)

[Claims] 1. A high-temperature inert gas that heats the soldering assembly to a soldering temperature. a vessel containing a gas; A fluid is present at the bottom of this vessel means and is a liquid at solderable temperatures. a tank, a means for contacting the tank and heating the tank to cause dissolution; A transducer that makes contact and vibrates at high frequency, and an adapter that encloses the solder inside. The assembly can be heated to a solderable temperature in an inert gas, and high-frequency vibration can be generated. As a result, highly reliable soldering work has been achieved. soldering equipment. 2. The heating means for the bath is thermally connected to the vessel means so that heating means in the vessel is thermally connected to the vessel means. Claims characterized in that the heat is supplied for heating the inert steam of The device according to scope 1. 3. adjacent the top of said vessel means to inhibit vapor dissipation from said vessel. 3. The device according to claim 2, further comprising means for stopping the movement. 4. The means for inhibiting vapor loss is provided with a cooling coil in the vessel above the tank. 4. The device according to claim 3, characterized in that: 5. The tank is used as a pot, solder is placed in the pot, and steam is introduced into the vessel. present, this vapor is characterized by having large halogenated organic molecules 5. The device according to claim 4. 6. The tank is used as a pot, solder is placed in the pot, and steam is introduced into the vessel. Once in existence, this vapor was characterized by having large halogenated organic molecules. An apparatus according to claim 1. 7. closed sides, an open top and a removable cover over this top a vessel having a bar adjacent to the open top of the lower side of the bar; A cooling means is provided in the lever vessel, and a solder pot is provided at the bottom of the vessel. , heat this solder pot and solder the interior of this vessel. When heated to a temperature that is possible, the heater and the transducer connected to this solder pot a power source connected to this transducer, and a power source connected to this transducer to energize this transducer. During soldering, high-frequency vibrations are transmitted to this solder pot, causing the solder to By placing the solder in the vessel and providing steam in the vessel, and steam are heated to a soldering temperature and the solder-containing assembly is The assembly is heated in steam to a solderable temperature and brought into contact with solder. When performing highly reliable flux-free soldering using A soldering device featuring: 8. high temperature steam is present in the vessel means and a fluid is present in the solder pot. The density of this fluid shall be greater than that of the assembly to be soldered, and this In particular, it is possible to suspend the assembly to be soldered on this fluid. 8. The device according to claim 7, characterized in that 9. Claim 8, wherein the fluid in the solder pot is solder. equipment. 10. The steam in the vessel means is an inert steam, and the inert steam is It is heavier than air and has an evaporation point higher than ambient temperature, which causes When the cooling coil is cooled to this ambient temperature, this vapor condenses and the 9. The device according to claim 8, wherein erasure is prohibited. 11. Claim 1, characterized in that the fluid in the solder pot is solder. The device according to item 10. 12. The solder-containing assembly is placed in inert steam, and the steam The temperature is high enough to melt the rice, Applying high frequency vibration to this assembly causes melting at the joints of this assembly. A soldering method characterized in that the soldering process is supported by providing solder that has been . 13. exposing said assembly to inert hot steam and applying mechanical vibrations; 13. The method according to claim 12, characterized in that the method is carried out simultaneously. 14. Applying high frequency mechanical vibrations to the assembly Float on the surface of a fluid that has a higher density than this high density is carried out by vibrating a fluid, and the high temperature insoluble vapor is 14. The method of claim 13, wherein the method is placed on the body. 15. exposing said assembly to inert hot steam and applying mechanical vibrations; Perform a heating step of the dense fluid and inert steam prior to the 15. The method according to claim 14, characterized in that the method is performed by: