JP3258204B2 - Soldering equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soldering apparatus in an exterior processing step of a semiconductor device.

[0002]

2. Description of the Related Art An exterior processing step of a semiconductor device involves an external lead.
The lead frame is coated with a metal coating of solder or tin for the purpose of improving the corrosion resistance of the do frame and the conformability of the solder when mounted on the board. The outer shape of the strip-shaped lead frame is shown in the circle of FIG. The semiconductor element is sealed with an insulating mold resin, and a plurality of mold parts 99 and an external lead 100 are connected to form a strip-shaped lead frame 101. In the exterior processing step, the strip-shaped lead frame is conveyed, wound and soldered.

A conventional soldering apparatus will be described with reference to FIG. FIG. 5A is a view schematically showing a soldering device. The left side of FIG. 5 (a) is an apparatus part for applying solder to the strip-shaped lead frame 101, and the right side of FIG. 5 (a) is an apparatus part for cleaning the strip-shaped frame 101 to which the solder is applied. . The strip-shaped frame 101 is conveyed by a frame feed roller 102 from the lower left of FIG. FIG. 5B is a diagram showing the internal structure of the solder coating device on the left side of FIG. 5A. The solder 104 is accommodated in a solder tank 107 and melted by a heater 103. The melted solder 104 is kept at a constant temperature by a temperature controller 105, and its surface is covered with an oxide film 106. The non-oxidized molten solder 104 is
The air is sucked from the suction port by the push propeller 109 rotated at 8, passes through the duct 110, and is discharged from the discharge port 1.
11 comes into contact with the transfer roller 113 rotating at a position higher than the liquid level. The transfer roller 113 is in contact with the strip frame 101, and the molten solder 104 attached to the transfer roller 113 is transferred to the strip frame 101 with the rotation of the transfer roller 113, The solder is continuously applied as the belt-like frame is transported by the rotation of the roller. In order to solder the strip frame 101 from both sides, two sets of solder coating devices having the same structure as above are installed symmetrically with respect to the strip frame 101.
The frame 101 soldered is a frame feed row.
Cleaning water 1 in the cleaning tank 115
After being cleaned by the ultrasonic cleaning device 16 and the ultrasonic cleaning device 117, the cleaning water is discharged from the cleaning tank, and the cleaning water adhering on the belt-like frame is removed by the air blow-118.

[0004]

The conventional soldering apparatus having the above-mentioned structure has a complicated structure, and in particular, has a movable body such as a jet mechanism or a rotary roller. Have difficulty. Further, the conventional soldering apparatus has the following problems.

First, in a conventional soldering apparatus,
The molten solder remaining after the soldering returns to the solder tank 107 and is jetted again for use. Since the molten solder is applied to the frame and has a property of gradually melting the material of the frame when it comes into contact with the frame, the molten solder remaining after soldering contains the material of the frame. The material is dissolved and contained. Since such solder returns to the solder tank 107 again,
The material of the molten solder 104 in the solder bath 107 gradually deteriorates. For this reason, in order to maintain the quality of soldering, it is necessary to periodically replace the molten solder. As described above, the conventional soldering apparatus requires a much larger amount of solder than the solder originally required for soldering, and is uneconomical.

Second, the above-mentioned solder replacement operation in the conventional soldering apparatus requires the operator to attach and detach the solder jet mechanism, adjust the solder jet mechanism, and remove and replenish the molten solder while the solder in the solder bath is melted. is there. Exchanging a large amount of molten solder at a high temperature in this large solder bath is very dangerous. Further, since the solder jet mechanism is complicated, the adjustment is very difficult.

Third, in the conventional soldering apparatus,
Soldering is performed at the contact point between the belt-shaped frame that is always being conveyed and the rotating transfer roller. For this reason, there is a problem that the belt-shaped frame at room temperature continuously contacts the transfer roller, and the temperature of the molten solder attached to the outer periphery of the transfer roller is lower than the temperature of the ejection port. is there. This causes an increase in the rotation speed of the transfer roller.

Fourth, in a conventional soldering apparatus,
As the transfer roller rotates at a high speed, the outer periphery of the transfer roller is gradually eroded by the solder, and the distance between the transfer roller and the frame at the contact point changes. In order to prevent poor soldering due to this, the conventional soldering apparatus requires periodic adjustment of the position of the transfer roller and replacement work, resulting in poor production efficiency.

Fifth, in the conventional soldering apparatus, the soldering speed is determined by a combination of the rotational speeds of the transfer rollers on both sides and the frame feed speed. By the way, the work of soldering the strip frame is originally performed as one of several types of assembly work in the assembly process of the plastic package, and this soldering apparatus is operated in connection with another apparatus. Things. Therefore, the transport speed of the frame cannot be freely set. On the other hand, in order to maintain good soldering quality, the frame needs to be quickly separated from the molten solder. Therefore, the soldering speed is generally higher than the frame transfer speed. As described above, it is very difficult to adjust the rotational speed of the transfer roller and to set the soldering speed to ensure sufficient quality while considering the frame transport speed in the connection operation with other devices. Have difficulty.

Lastly, in the conventional soldering apparatus, when the operation of the apparatus is stopped, a part of the band-shaped frame remains in the cleaning tank, so that the molding resin is sealed in the band-shaped frame. There is a possibility that the cleaning water permeates into the inside of the sealed portion and causes a defective semiconductor device product in the sealed portion. further,
Because the cleaning tank is wider than the frame,
It requires a large amount of washing water and is uneconomical.

It is an object of the present invention to provide a small-sized soldering which is capable of high quality soldering, is safe and easy to adjust, requires only a small amount of solder and washing water, is economical, has excellent production efficiency, It is to provide a device.

[0012]

Means for Solving the Problems To solve the above problems and achieve the object, a soldering apparatus of the present invention is configured as follows. That is, the soldering device of the present invention
A solder supply tank for melting the solder, a molten solder reservoir for applying molten solder from both sides to a part or the entire surface of the strip-shaped frame formed as a space between the upper and lower plates, and the molten solder reservoir. A belt-like frame conveying means for moving the belt-like frame between the upper and lower plates; and a supply means for supplying the molten solder from the solder supply tank to the molten solder reservoir, wherein the supply means is provided below. A narrow passage connecting the molten solder reservoir and the solder supply tank through an opening provided in the plate, wherein the distance between the upper and lower plates of the molten solder reservoir and the width of the supply means are narrow. The width of the passage is set within a range in which the surface tension of the molten solder acts so that the molten solder can be supplied by utilizing the capillary phenomenon of the molten solder.

[0013] As a result of taking the above measures, the following effects occur. That is, in the soldering apparatus according to the present invention, the solder is applied to the frame by passing the frame through the molten solder reservoir. The molten solder reservoir and the solder supply tank for melting the solder are 0.05 to 1.00.
The connection is made at a connection portion having a width of about mm, and the solder is supplied to the molten solder reservoir using the capillary action of the solder. Therefore, as the solder is applied to the frame, the molten solder is replenished from the supply tank by an amount that the frame is removed from the molten solder reservoir, and the solder remaining after soldering returns to the supply tank. There is no. Therefore, the quality of the molten solder in the supply tank is not degraded, and soldering with stable quality can be always performed. Further, since there is no need to periodically change the molten solder in the supply tank as in the related art, it is possible to provide a device that does not require dangerous work and has high production efficiency.

Further, the soldering apparatus according to the present invention supplies the solder by utilizing the capillary phenomenon of the solder, and melts the molten solder such as a molten solder pushing propeller, a duct, and a jet mechanism from a supply tank as in the prior art. Does not require power to supply to Further, since the soldering is performed by the frame passing through the molten solder reservoir formed by utilizing the surface tension of the solder, two sets of transfer rollers are used as in the prior art.
No soldering or molten solder supply mechanism is required. As a result, it is possible to significantly reduce the size and cost of the device, and to further reduce power consumption during operation.

In the soldering apparatus according to the present invention, the lower plate and the upper plate forming the molten solder reservoir for applying the solder to the strip frame are fixed. Therefore, erosion of the lower plate and the upper plate by the molten solder is very small as compared with the conventional transfer roller rotating at a high speed. For this reason, there is no need to adjust and replace the transfer roller, which has conventionally caused the production efficiency to be reduced, and the production efficiency can be improved.

In the soldering apparatus according to the present invention, since the lower plate and the upper plate are fixed, the soldering speed is set only by the frame feed speed. Therefore, the transfer ro
This eliminates the need for complicated adjustments by both the rotation speed of the roller and the frame feed speed, thereby improving production efficiency. Further, since the belt-like frame repeatedly moves forward and backward, the transport speed of the belt-like frame averaged over time is smaller than the speed at which the frame separates from the solder during forward movement. As described above, in order to perform high quality soldering, the frame needs to be quickly separated from the solder. That is, according to the present invention, the soldering speed required for high-quality soldering and the transport speed corresponding to the connection operation with another device can be realized at the same time.

In the soldering apparatus according to the present invention, as the means for transporting the strip-shaped frame, the strip-shaped frame is moved forward by a set distance, and then is moved backward by a set distance shorter than that. It is preferable to provide a mechanism for transporting the band-like frame by repeating the above-mentioned stop of 5 seconds or less as one cycle, and by repeating this cycle. Since the soldering is performed during the forward, backward and stop cycles in the inside, the preheating is sufficiently performed. Therefore, it is possible to prevent the temperature of the molten solder from lowering due to the contact with the strip frame at room temperature as in the related art.

In the soldering apparatus according to the present invention, there is provided a cleaning liquid spraying apparatus as a cleaning apparatus for cleaning the strip-shaped frame after the application of the solder, and a gas jetting apparatus for blowing off the cleaning liquid attached to the strip-shaped frame. Is preferably provided. If such a cleaning device is used, the strip-shaped frame after soldering is used.
The system is cleaned by a shower system and drained quickly by an air blower. Therefore, the strip-shaped frame does not stop in the washing water when the apparatus is stopped as in the related art.
It is possible to prevent the cleaning water from entering the mold enclosing resin portion attached to the strip frame, and to reduce the defective rate of semiconductor products in the mold resin.

In the soldering apparatus according to the present invention, it is preferable that the lower plate and the upper plate are configured so that they can be easily attached to and detached from the fixed portion having the reference surface. In this way, the lower plate and the upper plate can be easily exchanged for the shape of each product or the shape suitable for the soldering conditions, and it is possible to support various kinds of products.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a soldering device according to the present invention. The soldering device according to the present invention is 2
Roughly divided into two parts. That is, the left side of FIG. 1 is an apparatus portion for applying solder to the band-shaped frame 1, and the right side of FIG. 1 is an apparatus portion for cleaning the band-shaped frame 1 after applying the solder. The strip-shaped frame 1 enters the apparatus from the left side of FIG.
1 is conveyed rightward in FIG.

The solder application unit (left side in FIG. 1) comprises a solder supply tank 4 for melting solder, a connecting portion 5, a lower plate 6, and an upper plate 7. A molten solder reservoir 8 is formed between the lower plate 6 and the upper plate 7, and the band-like frame 1 passes through the molten solder reservoir 8 to apply the solder.

An apparatus portion for cleaning the strip-shaped frame after the solder application (right side in FIG. 1) includes a cleaning liquid spraying apparatus 9 and a gas jetting apparatus 10 for blowing off the cleaning liquid adhering on the strip-shaped frame.
It has.

The solder coating device (left side in FIG. 1) will be described in more detail with reference to an enlarged view. FIG. 2 is an enlarged perspective view of the solder coating device (left side in FIG. 1). Further, FIG.
2A is a cross-sectional view taken along the line AA ′ of FIG. 2, and FIG. 3B is a cross-sectional view taken along the line BB ′ of FIG.

The linear wire solder 11 is sent into the solder supply tank 4 by the roller 12 and melted by the heater 13. When the liquid surface of the molten solder 14 reaches the liquid level sensor 15, the roller 12 stops feeding the wire solder 11. The temperature of the molten solder 14 is controlled by a temperature controller 16 and stored in the solder supply tank 4. The molten solder 14 is supplied to the suction port 1 installed in the lower part of the solder supply tank 4.
The molten metal 7 is supplied to the molten solder reservoir 8 from the outlet 18 through the connecting portion 5. This supply is performed by utilizing the capillary phenomenon of the molten solder 14. For this purpose, the width of the connecting portion 5 is set to 0.
The width is reduced to about 0.05 to 1.00 mm, preferably about 0.4 to 1.0 mm, and the inside of the connecting portion 5 is subjected to a treatment for ensuring the adhesion to the molten solder. Further, the molten solder reservoir 8
Is formed such that a constant amount of molten solder is always stored in the space between the lower end 19 of the upper plate 7 and the upper end 20 of the lower plate by utilizing the surface tension of the molten solder 14.
By changing the distance between the lower end portion 19 of the upper plate 7 and the upper and lower portions 20 of the lower plate 6 by the adjusting screw 21, the shape of the molten solder reservoir 8 is changed according to the thickness of the strip frame 1. Can be done. The lower plate 6 is fixed to the nozzle fixing portion 22 and the upper plate 7 is fixed to the upper plate fixing portion 23 by fixing screws 24 and 25, respectively. The ejection port 18 is formed by a gap between the plurality of lower plates 6. Note that the supply of the molten solder 14 is
Since the effect of gravity is negligible, the connecting portion 5 and the ejection port 18 may be formed in any direction with respect to gravity. Similarly, since the molten solder reservoir 8 is formed by utilizing the surface tension of the molten solder 14 and the influence of gravity can be ignored, the upper plate 7 and the lower plate 6 may be formed in any direction.

The temperature of the molten solder in the molten solder reservoir 8 is maintained at the same temperature as the temperature of the molten solder 14 in the solder supply layer 4 through the connecting portion 5. Further, by installing the heater 26 and the temperature controller 27 also on the upper plate fixing portion 23, the upper plate 7 is always maintained at a constant temperature by these.
If the molten solder in the molten solder reservoir 8 is prevented from lowering in temperature due to contact with the strip-shaped frame 1, the temperature can be maintained more favorably. The upper plate 7 is moved upward by an upper die drive shaft 28 connected to the upper plate fixing portion 23, and the lower plate 6 is moved downward by a lower die drive shaft 29 connected to the nozzle fixing portion 22. The part 8 can be separated vertically. Due to this separation, even when the strip-shaped frame 1 stays in the molten solder reservoir 8 for a long time, heat conduction in the solder supply tank 4 to the semiconductor element by the heat source can be cut off, thereby preventing a trouble due to heat. . Further, even when the plate thickness changes at the joint portion of the band-shaped frame 1, the passage of the band-shaped frame 1 is not hindered.

The strip frame 1 is moved forward by, for example, about 42 mm, then moved backward by about 35 mm by the frame feed roller 2, and then stopped for, for example, 5 seconds. The forward, backward and stop are defined as one cycle, and the cycle is repeated to convey the strip-shaped frame 1. That is, the difference between the forward and backward movements, that is, 7 mm in this embodiment, is the transport distance of the belt-shaped frame 1 in one cycle. Stripe frame 1
Must be shorter than the forward distance in order to be transported. By appropriately setting the difference between the forward movement and the backward movement, the transport speed of the frame 1 can be adjusted in accordance with, for example, the transport speed of another device connected to the present apparatus. By appropriately setting the advance speed, the speed at which the frame 1 separates from the molten solder reservoir 8 can be adjusted so that high-quality soldering is ensured. As described above, in the soldering apparatus according to the present invention, the frame conveying speed and the soldering speed can be set separately.

The stop of 5 seconds is for the purpose of sufficiently preheating the band-like frame 1 which has entered the molten solder reservoir 8 by heat conduction from the molten solder reservoir 8. At the same time, if this stop is carried out for a long time, heat is also conducted to the semiconductor element, which may cause deterioration or performance deterioration of the element. Therefore, this stop is desirably performed within 5 seconds. Then, the strip frame 1
While passing through the molten solder reservoir 8 while repeatedly moving forward and backward, solder is applied from both sides of the strip-shaped frame 1. At this time, the strip-shaped frame 1 needs to be transported in the molten solder reservoir 8 so as not to touch the upper plate 7 and the lower plate 6, but is transported in parallel with the upper plate 7 and the lower plate 6. Need not be.

Further, the forward and backward distances of the strip frame are appropriately set according to the lengths of the upper plate 7 and the lower plate 6 and the preheating and heat radiation characteristics of the strip frame 1. That is, the strip-shaped frame
The individual leads on the system 1 are preferably subjected to at least one cycle of advance, retreat and stop in a molten solder reservoir 8 formed between the upper plate 7 and the lower plate 6, It is withdrawn from the molten solder reservoir 8. In this case, the strip-shaped frame 1
Must be smaller than the length of the upper plate 7. Also, the lead which has been preheated and exited in the molten solder reservoir 8 must be re-entered into the molten solder reservoir 8 by receding before being radiated and returned to room temperature. In this case, the retreat must be performed promptly and earlier than the lead heat radiation time, and the retreat distance is determined from this. For the above reasons, it is preferable that the forward distance is appropriately set within the range of 5 to 120 mm and the reverse distance is set within the range of 3 to 100 mm.

With the application of the solder, the amount of solder removed from the molten solder reservoir 8 by the strip-shaped frame 1 is supplied by utilizing the capillary phenomenon of the molten solder in the connecting portion 5. Since the molten solder does not come into direct contact with air, it is supplied without being oxidized.
The supplied molten solder is stored between the lower plate 6 and the upper plate 7 due to surface tension, and only the side surface is slightly oxidized, but has little effect on the quality of the molten solder.

In the soldering apparatus of the present embodiment,
The lower plate 6 and the upper plate 7 are configured to be easily detachable.
That is, the lower plate 6 is fixed to the soldering nozzle fixing reference surface 30 formed in the nozzle fixing portion 22 by the fixing screw 24, and the upper plate 7 is fixed to the upper plate fixing reference surface 31 formed in the upper plate fixing portion 23. Is fixed by a fixing screw 25. By loosening the fixing screws 24 and 25, the lower plate 6 and the upper plate 7 can be easily removed. FIG. 4A shows a state in which the upper plate 7 is detached from the upper plate fixing part 23 and the lower plate 6 is detached from the nozzle fixing part 22. Further, the lower plate 6 and the upper plate 7 are inserted into the soldering nozzle fixing reference surface 30, the upper plate 7 is inserted into the upper plate fixing reference surface 31, and the fixing screws 24 and 25 are tightened. It can be easily restored and requires only minor adjustments thereafter.

As described above, in the soldering apparatus of the present invention, since the lower plate 6 and the upper plate 7 have a structure that can be easily attached and detached, the length of the lower plate 6 and the upper plate 7 with respect to the frame advancing direction. Can be varied independently of each other. For example, the length of the lower plate 6 is 0 to 15 m compared to the length of the upper plate 7.
By reducing the length m, the amount of solder adhering on the frame when the frame separates from the molten solder can be changed, and the thickness of the applied solder can be reduced. Further, when the transport speed is very low, the frame 1 stays in the molten solder reservoir 8 for a longer time than the life of the flux, and the quality of soldering may be deteriorated. This can be prevented by shortening 7. On the other hand, when the transport speed is extremely high, the length of the molten solder reservoir 8 is increased so that the frame 1 stays in the molten solder reservoir 8 for a sufficiently long time to perform high quality soldering. There is a need. This can be easily realized by making the lower plate 6 and the upper plate 7 longer. That is, by changing the lengths of the lower plate 6 and the upper plate 7, the time during which the frame stays in the molten solder reservoir 8 can be adjusted, and the setting range of the transport speed of the frame can be expanded. is there. For example, lower plate 6 and upper plate 7
When the length of the frame is changed to 10 to 70 mm, the frame conveyance speed is controlled to 0.01 to 70 mm while maintaining the high quality of the soldering.
It can be changed freely within the range of 1.0 mm / min.

Further, since the lower plate 6 and the upper plate 7 can be easily attached and detached, the belt-shaped frame 1 including different types of semiconductor elements has a shape adapted to the mold resin shape of the type. The lower plate 6 and the upper plate 7 can be easily replaced. For example, as shown in FIG. 3A, the lower plate 6 and the upper plate 7 having the grooves 32 and 33, respectively, can be mounted to partially widen the gap between the upper end of the lower plate 6 and the lower end of the upper plate 7. Molten solder reservoir 8
Is formed by the surface tension of the solder, the molten solder reservoir 8 is not formed in such a portion where the distance between the upper end of the lower plate 6 and the lower end of the upper plate 7 is wide.

FIG. 4B shows that the mold resin 35 is
4 shows a state where the vehicle passes through No. 4. Thus, the distance a between the lower end of the mold resin 35 and the upper end surface of the lower plate 6 is set to
By making the distance larger than the distance b between the upper end of the upper plate 5 and the lower end surface of the upper plate 7, a structure can be obtained in which the flux (a material for securing wettability at the time of soldering) attached to the band-like frame can easily enter this space. ing. Further, as shown by a broken line in FIG. 3B, the groove 32 formed in the lower plate 6 is inclined so that the depth c on the entry side with respect to the transport direction of the strip-shaped frame 1 is set on the exit side. By making the depth deeper than the depth d, it is possible to further facilitate the penetration of the flux and to easily discharge the contaminated flux.

The strip-shaped frame 1 to which the solder has been applied is conveyed to the cleaning portion. The cleaning device will be described again with reference to FIG. The strip-shaped frame on which the solder is applied is a cleaning sheet 3
6 and is washed by a washing water shower 9;
Draining is performed by the air blower 10 and discharged. The dirt is slid down the shout 36 together with the washing water and discharged from the drain 37. When the soldering equipment stops, the water shower
9 stops and, with a slight delay, the air blow 10 also stops.

As described above, in the soldering apparatus according to the present invention, the solder is supplied from the solder supply tank to the molten solder reservoir using the capillary phenomenon of the solder. Further, the molten solder reservoir is formed between the upper and lower plates using the surface tension of the molten solder.
That is, the soldering device according to the present invention has a very simple structure as compared with the conventional device. In particular, since the apparatus according to the present invention does not have any moving parts such as a jet mechanism and a transfer roller which are necessary for the conventional apparatus, the apparatus according to the present invention can be adjusted very easily.

Further, in the soldering apparatus according to the present invention, the molten solder is replenished from the supply tank by an amount consumed in the molten solder storage portion with the soldering of the frame, and the solder remaining after the soldering is supplied to the supply tank. Never return to. Therefore, the quality of the molten solder in the supply tank does not deteriorate,
Soldering with stable quality can always be performed. Further, since there is no need to periodically change the molten solder in the supply tank as in the related art, it is possible to provide a device that does not require dangerous work and has high production efficiency.

Further, the soldering apparatus according to the present invention supplies the solder by utilizing the capillary phenomenon of the solder, and melts the molten solder such as a propeller, a duct, and a jet mechanism with a molten solder from a supply tank as in the prior art. Does not require power to supply to Further, since the soldering is performed by the frame passing through the molten solder reservoir formed by utilizing the surface tension of the solder, two sets of transfer rollers are used as in the prior art.
No soldering or molten solder supply mechanism is required. As a result, it is possible to significantly reduce the size and cost of the device, and to further reduce power consumption during operation.

Further, in the soldering apparatus according to the present invention, since the soldering is performed while the strip frame repeatedly advances, moves backward and stops in the molten solder reservoir, the strip frame is sufficiently preheated. You. Therefore, the temperature of the molten solder does not drop due to the contact of the belt-shaped frame at room temperature as in the prior art, and the quality of soldering does not deteriorate. Further, a heat source heater for controlling the temperature of the molten solder reservoir may be provided on the upper plate fixing portion close to the molten solder reservoir. In this case, the temperature of the molten solder can be more stably maintained, and the quality of soldering can be further improved.

In the soldering apparatus according to the present invention, the lower plate and the upper plate forming the molten solder reservoir for applying the solder to the belt-like frame are fixed. Therefore, erosion of the lower plate and the upper plate by the molten solder is very small as compared with the conventional transfer roller rotating at a high speed. Therefore, it is not necessary to adjust and replace the transfer roller, and the production efficiency is improved.

Further, in the soldering apparatus according to the present invention, since the lower plate and the upper plate are fixed, the soldering speed is free.
It is set only by the system feed speed. Therefore, complicated adjustment by both the rotation speed of the transfer roller and the frame feed speed as in the related art is not required, and the operation is simplified. Further, the transport speed of the strip frame is set by the difference between the forward and backward travels, and the soldering speed is set only by the forward travel speed. That is, since the frame transfer speed and the soldering speed can be set separately, the soldering speed required for high-quality soldering and the transfer speed corresponding to the connection operation with other devices are simultaneously set. Can be realized.

In the soldering apparatus according to the present invention, the strip-shaped frame after soldering is washed by a shower system, and drained quickly by an air blower. Therefore, the strip-shaped frame does not stop in the washing water when the apparatus is stopped as in the prior art, so that the washing water is prevented from entering into the mold sealing resin part attached to the strip-shaped frame. Semiconductor product in the solder resin can be reduced in defect rate.

Further, in the soldering device according to the present invention, the lower plate and the upper plate can be easily and separately attached to and detached from the fixed portion having the reference surface. For this reason, it is possible to easily replace the lower plate and the upper plate with a shape suitable for the shape of each product and soldering conditions. First, by making the upper plate shorter than the lower plate, the amount of solder adhering on the frame when the frame separates from the molten solder can be changed, and the thickness of the solder can be reduced. . Second, by changing the length of the lower plate and the upper plate to adjust the time that the frame stays in the molten solder, it is possible to greatly widen the setting range of the transport speed. Third, a groove is formed in each of the lower plate and the upper plate so that the mold resin passes through the groove, so that soldering to the mold resin can be prevented. Fourth, by using a lower plate and an upper plate having grooves adapted to the mold resin shape of each product, it becomes possible to support various types of products. Fifth, the distance between the end surface of the groove formed in the lower plate and the lower end surface of the mold resin is made wider than the distance between the end surface of the groove formed in the upper plate and the upper end surface of the mold resin. The structure is such that the flux can easily enter this groove. Sixth, by making the depth of the groove formed in the lower plate deeper on the entry side than the exit side with respect to the direction of transport of the frame, the flux more easily enters the groove and becomes contaminated. A structure in which the flux is easily discharged can be provided.

[0043]

As described above, according to the present invention, there are provided a mechanism capable of high-quality soldering and a safe and simple adjusting mechanism, which is economical and requires only a small amount of solder and cleaning water. It is possible to provide a small-sized soldering apparatus excellent in production efficiency.

[Brief description of the drawings]

FIG. 1 is a diagram showing a structure of a soldering apparatus of the present invention.

FIG. 2 is an enlarged perspective view of the soldering device of the present invention.

FIG. 3 is a sectional view of the soldering apparatus of the present invention.

FIG. 4 is an exploded view of the soldering device of the present invention.

FIG. 5 is a diagram showing a structure of a conventional soldering device.

[Explanation of symbols]

1 ... strip-shaped lead frame, 2 ... frame feed roller, 4
... Solder supply tank, 5 ... Connection part, 6 ... Lower plate, 7 ... Upper plate, 8 ...
Molten solder reservoir, 9: water shower, 10: air blow,
11: wire solder, 12: roller, 13: heater, 1
4: molten solder, 15: liquid level sensor, 16: temperature controller,
Reference numeral 17: suction port, 18: ejection port, 21: adjusting screw, 22: nozzle fixing section, 23: upper plate fixing section, 24, 2
5: fixing screw, 26: heater, 27: temperature controller, 28
… Upper drive shaft, 29… lower drive shaft, 32,
33 ... groove, 34 ... space, 35 ... mold resin, 36 ...
Cleaning Shut, 37 ... Drainage port

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-112392 (JP, A) JP-A-5-267528 (JP, A) JP-A 4-135057 (JP, A) JP-A-5-112 190403 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H05K 3/34 H01L 23/50

Claims (5)

(57) [Claims] In a soldering apparatus for applying a molten solder to a part or the entire surface of a strip frame in an assembling process of a semiconductor device, the strip frame formed as a space between a solder supply tank for melting solder and upper and lower plates. A molten solder reservoir for applying molten solder to both or part of the entire surface of the substrate, a band-shaped frame transporting means for moving the band-shaped frame between the upper and lower plates through the molten solder reservoir, and the molten solder from the solder supply tank. Supply means for supplying the molten solder to the reservoir, wherein the supply means has a narrow passage connecting the molten solder reservoir and the solder supply tank through an opening provided in a lower plate. The distance between the upper and lower plates of the molten solder reservoir and the width of the narrow passage of the supply means make it possible to supply the molten solder utilizing the capillary phenomenon of the molten solder. It is set within the range in which the surface tension of the molten solder acts, and the belt-shaped frame conveying means
Is a forward movement of a set distance of the strip frame,
Subsequent backward movement set for a shorter distance
And the subsequent stop as one cycle, and repeat this cycle.
A soldering device for moving the strip-shaped frame by turning the soldering frame back . 2. The soldering apparatus according to claim 1, wherein the lower plate and the upper plate are separately detachable from a fixed portion. 3. The soldering apparatus according to claim 1, wherein lengths of the lower plate and the upper plate in the frame transport direction are individually variable. 4. have a respective said lower plate said upper groove, passes through the semiconductor device encapsulating resin portion within said groove that is included in the frame, between said lower plate said semiconductor device encapsulated resin lower surface The interval is set to be larger than the interval between the upper plate and the upper surface of the semiconductor device enclosing resin portion, and the depth of the groove of the lower plate is deeper on the entry side than on the exit side in the frame transport direction. 2. The soldering apparatus according to claim 1, wherein the soldering apparatus is set. 5. A soldering apparatus for applying molten solder to a part or the entire surface of a strip frame in an assembling process of a semiconductor device, wherein the strip frame is formed by utilizing a solder supply tank for melting solder and a capillary phenomenon of the molten solder. some or comprising the molten solder reservoir for coating the entire surface melt the solder, and a band-shaped frame conveying means for moving the strip frame so as to pass through the molten solder reservoir, the shape frame conveying hand
The step is a forward movement of the strip frame for a set distance,
Subsequent backward movement set for a shorter distance
And the subsequent stop as one cycle, and repeat this cycle.
A soldering device for moving the strip-shaped frame by turning the soldering frame back .