JPH11103159A - Head unit for soldering apparatus and soldering method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide head unit by which the relative distance between the holding member of solder and a board can be controlled with high accuracy, by a method wherein a movement part in which the holding member of a punch and that of a die are attached so as to be freely movable to an approach direction to the board and which can be moved freely to the approach direction to the board is provided, and a sensor which detects the relative distance between a body part in the approach direction to the board and the movement part is provided. SOLUTION: A tension spring 727 is installed between a support arm 726 and an arm 711a at a raising and lowering plate 71, and the raising and lowering plate 711 is attached to a guide member 723 via a slider so as to be freely movable to the up-and-down direction. A movement part 72 is supported at a prescribed spring force by a constant tension spring 724 and the tension spring 727. The spring force is set in such a way that, when solder which is stuck to the tip of an optical fiber 714 is stuck to a desired position on a board, a body part 71 can be moved upward to such an extent that the solder is not crushed too much by a force acting on the solder from the optical fiber 714. A sensor 73 is connected to a controller in a housing via a cord connected to an upper-part connector 73d, and the relative distance between the arm 711a and the board can be controlled with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soldering head unit for forming fine solder bumps by adhering solder to a desired position on a substrate, and a soldering method using the same.

[0002]

2. Description of the Related Art When an IC chip or the like is mounted on a printed circuit board to form an IC module, a printed circuit and an IC module are used.
It is necessary to previously form a solder bump for electrically contacting and fixing a C chip or the like on a substrate. In recent years, the number of solder bumps has been increased and the number of solder bumps has been reduced due to the integration of IC modules.

Conventionally, solder bumps are formed by applying a solder paste to a printed circuit board having a copper pad and then heating and reacting the solder paste on the copper pad by a reflow furnace.
Thereafter, it has been common practice to collectively form solder bumps on the copper pad by removing the solder paste other than the copper pad by washing. However, in order to form solder bumps on individual copper pads, the present inventors applied a small amount of solder paste to the tip of an optical fiber having a small cross section, and applied this solder paste to a copper pad on a substrate. Thereafter, a solder bump forming method and a solder bump forming apparatus for forming a solder bump by heating and melting are proposed (Japanese Patent Application No. 8-3268).
No. 54, Japanese Patent Application No. 9-28240).

[0004]

When an optical fiber is used, good solder bumps may not be formed unless the solder paste attached to the tip of the optical fiber is securely attached to the copper pad. In addition, when the solder paste is applied to the copper pad, if the solder paste is crushed too much at the tip of the optical fiber, the solder paste is cut off, preventing the formation of a good solder bump.

Further, after the solder paste is applied to the copper pad, if the tip of the optical fiber is not separated from the copper pad by an appropriate distance, the molten solder will interfere with the tip of the optical fiber when the amount of solder is large, The shape of the formed solder bump may be distorted or a divided solder ball may be generated. When using the heating light transmitted through the optical fiber as a heating source to melt the solder, if the distance between the tip of the optical fiber and the solder paste is too large, the energy of the heating light is dispersed and the solder is sufficiently melted. May not be possible.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it has been proposed to increase the relative distance between the member holding the solder and the substrate when the solder is attached to a desired position on the substrate to form minute solder bumps. It is an object of the present invention to provide a head unit for a soldering apparatus that can be controlled with high accuracy and a soldering method using the same.

[0007]

Means for Solving the Problems In a head unit for a soldering apparatus for forming minute solder bumps by adhering minute solder to a desired position on a substrate, the die is inserted into a through hole provided in the die so as to be freely retractable. Having a punch and a holding member for holding the die, a main body for adhering a small amount of solder filled in the through hole to the substrate, and the holding member being movable along a direction approaching the substrate. And a movable unit movable in a direction approaching the substrate, and a sensor for detecting a relative distance between the main unit and the movable unit in a direction approaching the substrate.

Preferably, the die is a ferrule,
The punch is an optical fiber connected to a heating light source.
Also preferably, the main body has solder extruding means movable along a direction approaching the substrate, and the relative position between the punch and the die is changed by the solder extruding means.

[0009] More preferably, the holding member is attached to the moving portion via a guide member. Preferably, the holding member is elastically suspended by a spring provided in the moving unit. Preferably, the moving section has a lifting stage movable along a direction approaching the substrate.

Further, in the present invention, in order to achieve the above object, after lowering the main body to allow the solder to adhere to the substrate, a distance corresponding to the relative distance between the main body and the moving part measured by a sensor is taken into account. Then, the moving portion is raised to form a gap between the solder attached to the substrate and the main body. Here, in this specification, the solder includes a solder paste obtained by adding flux to solder.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a solder bump forming apparatus to which a head unit of the present invention is attached will be described with reference to FIGS. 1 to 16 as an embodiment of a head unit for a soldering apparatus of the present invention and a soldering method using the same. This will be described in detail. As shown in FIGS. 1 to 4, a solder bump forming apparatus (hereinafter simply referred to as “bump forming apparatus”) 1 includes an X-axis robot 3, two Y-axis robots 4, a conveyor 5,
A preheating unit 6, a head unit 7, and a supply unit 8 are provided, and the operation is controlled by a controller 9 such as a programmable computer according to a preset operation flow. A monitor 2a is installed on the upper part of the housing 2.

The X-axis robot 3 and the Y-axis robot 4 use ball screws, respectively. X axis robot 3
Are arranged in parallel with the conveying direction of the conveyor 5, and two Y
The axis robot 4 is arranged in a direction perpendicular to the direction of transport of the conveyor 5. Then, the X-axis robot 3 has two Y
The head unit 7 is supported movably in the axial direction while being supported by the axis robot 4, and is moved by the Y-axis robot 4 in a direction orthogonal to the transport direction of the conveyor 5. Therefore, in the following description, the direction of conveyance of the conveyor 5, the direction of the axis of the X-axis robot 3 is the X-axis direction, the direction perpendicular to the direction of conveyance of the conveyor 5, and the direction of the axis of the Y-axis robot 4 is the Y-axis. Called direction.

The conveyor 5 conveys a printed circuit board (hereinafter, simply referred to as a “substrate”) S, which is carried in from a carry-in port (not shown) provided on the right side of the housing 2, to the preheating unit 6,
Here, as described later, the substrate S on which the solder bumps are formed at desired positions is carried out to a carry-out port (not shown) provided on the left side of the housing 2. The preheating section 6 is a section for preheating the conveyed substrate S for a predetermined time, and is arranged at a lower portion in the middle of the conveyor 5 in the X-axis direction. A preheating plate 6a having a built-in heater is arranged to be able to move up and down. Here, the heating temperature of the substrate S is preferably as high as possible within a range where problems such as oxidation do not occur in the substrate S, for example, a temperature of less than 100 ° C. As the solder, a solder paste, for example, a micro solder manufactured by Harima Chemicals, Inc. is used. This solder paste has a particle size of 1
It is made by mixing and dispersing 5 to 30 μm solder particles in a paste, and has a strong activity and a melting point of 183 ° C. When using this solder paste, the temperature of the substrate S should be 80-100
It is good to preheat to ℃.

The head unit 7 is a unit for attaching solder to a desired position on the substrate S, for example, a copper pad.
It is attached to the axis of the axis robot 3 so as to be movable in the axial direction. The head unit 7 includes a main body 71, a moving unit 72, and a sensor 73, as shown in FIGS. The main body 71 is a portion for attaching the solder supplied to the distal end of the optical fiber 714 described later by the supply unit 8 to the substrate S, and includes a lifting plate 711, a first lifting stage 712, a ferrule 713, and an optical fiber 714. I have.

The elevating plate 711 is vertically movably attached to a guide member 723, described later, of the moving unit 72 via a slider 715, and a constant tension spring 724 connected to the upper portion applies a predetermined spring force to the moving unit 72. It is elastically supported. The elevating plate 711 is a vertically long holding member that holds the ferrule 713 and the optical fiber 714, and has a horizontally extending arm 711a formed below. On the side of the lifting plate 711,
As shown in FIGS. 3 and 4, an upper stopper 711b and a lower stopper 711c using a screw that cooperates with a support arm 726 described later to regulate the relative vertical position of the moving unit 72 and the main body 71. Installed.

The first elevating stage 712 is a stage utilizing a feed screw, and has a support plate 712a attached to the elevating plate 711, a main body 712b, a screw shaft 712c, and a slider 712d which moves in the vertical direction. The ferrule 713 is a single-core ferrule screwed into a mounting hole formed at the tip of the arm 711a, and functions as a die. Optical fiber 714
Is fixed to a fixed plate 716 attached to the slider 712d at a position slightly away from the tip by a pressing plate 717, and the tip extending downward is inserted into the fiber hole of the ferrule 713 so as to be freely retractable. Optical fiber 714, ferrule 713
It is fixed to the fixing plate 716 by appropriately adjusting the amount of insertion into the fiber hole. The optical fiber 714 sets the desired amount of solder embedded in the space formed by the fiber hole and the optical fiber 714 by appropriately adjusting the insertion amount of the ferrule 713 into the fiber hole by the first lifting stage 712. be able to. On the other hand, the other end of the optical fiber 714 is wound around a winding frame 728a (see FIGS. 6 and 7) of the moving section 72, which will be described later, is subjected to extra length processing, and is then connected to a laser diode module 725 (see FIG. 7). I have.

The moving section 72 supports the lifting plate 711 so as to be movable in the direction approaching the substrate S, and is configured to be movable in the direction approaching the substrate S. The base 721, the second lifting stage 722, the guide member 723, a winding frame 728a, and a laser diode (hereinafter simply referred to as “LD”) module 725
have. The base 721 is attached to the axis of the X-axis robot 3 so as to be movable in the axial direction, and a constant tension spring 724 is attached to the upper part. The base 721 is shown in FIGS.
As shown in FIG. 7, a photo sensor 721a for detecting that the head unit 7 is at the raised position is attached to the side. The second elevating stage 722 is configured in the same manner as the first elevating stage 712, and has a support plate 722 attached to the base 721.
a, a main body 722b, a screw shaft 722c, and a slider 722d that moves up and down.

The guide member 723 is attached to the slider 722d as shown in FIGS.
The movement of the slider 715 provided in the vertical direction is guided by two guide rails 723a (see FIG. 6). A detection piece 723b (see FIG. 6) for detecting that the head unit 7 is at the ascending position in cooperation with a photo sensor 721a provided on the base 721 is attached to a side portion of the guide member 723. Here, as shown in FIGS. 4 and 6, a support arm 726 that supports a sensor 73 described below is attached to the guide member 723.

As shown in FIG. 4, a tension spring 727 is provided between the support arm 726 and the arm 711a of the elevating plate 711. Therefore, the elevating plate 711 is vertically movably attached to the guide member 723 via the slider 715, but is supported by the moving portion 72 with a predetermined spring force by the constant tension spring 724 and the extension spring 727. . This spring force is about several grams to several tens of grams, at which the solder acting on the solder from the optical fiber 714 is not excessively crushed by the force acting on the solder from the optical fiber 714 when the solder attached to the tip of the optical fiber 714 is applied to a desired position on the substrate S The value is set so that the main body 71 can move upward.

The winding frame 728a is, as shown in FIGS.
A cylindrical member attached to an attachment plate 728 provided on the side surface of the base 721. The center member presses the side surface of the elevating plate 711 and rattles the main body portion 71 and the moving portion 72 as the head unit 7 moves. The cylinder 729 which suppresses is installed. On the other hand, as shown in FIG.
It is provided above the mounting plate 728, emits heating light to the optical fiber 714, and melts the solder supplied from the supply unit 8. At this time, it is preferable that the heating light has a wavelength in the range of 800 to 1000 nm when the micro solder is used as the solder.

The sensor 73 is a contact-type displacement sensor which is supported by a support arm 726 provided on the moving section 72 and detects a relative distance between the lifting plate 711 and the moving section 72. The sensor 73 includes a body 73a fixed to the support arm 726, and a lower end of a rod 73b extending downward from the body 73a.
A contact 73c that is in contact with the upper surface of the arm 711a of the elevating plate 711 is attached. Here, the sensor 73 is connected to the controller 9 of the housing 2 via a cord (not shown) connected to the upper connector 73d, and controls the relative distance between the arm 711a and the substrate S with high accuracy. However, in the present embodiment, a contact type displacement sensor is used as the sensor 73, but a non-contact type sensor such as a laser displacement meter may be used.

The supply unit 8 is shown in FIGS.
As shown in (a), it is arranged at the back right of the housing 2. The supply unit 8 is a unit that supplies solder to the main body 71 of the head unit 7, and is disposed on a base 80 provided in the housing 2 as shown in FIGS. , Cutting part 83, monitor part 8
4 and a moving stage 85.

The cleaning section 81 is for cleaning the tip of the ferrule 713 and the optical fiber 714 to which the solder is supplied.
As shown in the figure, the moving stage 85 is disposed between the embedding portion 82 and the cutting portion 83. As shown in FIG. 11, an opening 81a for inserting a ferrule 713 attached to an arm 711a of the head unit 7 is formed in an upper portion of a cylindrical member, an air nozzle 811 is provided in an upper portion, and an injection nozzle 812 is provided in the cleaning portion 81. Are provided respectively. Air nozzle 8
Numeral 11 injects pressurized air sent from a factory air supply source toward the tip of the ferrule 713. On the other hand, the injection nozzle 812
Is a cleaning liquid supplied from a cleaning liquid tank 86 provided on the base 80, for example, alcohol, and a ferrule 713.
Injecting toward the tip of. Here, the alcohol sprayed from the spray nozzle 812 is collected from a suction port (not shown) provided at a lower part of the cleaning unit 81.

The embedding portion 82 is a portion for embedding solder in the fiber hole of the ferrule 713, as shown in FIGS.
(A), as shown in FIG. 12, provided on a moving stage 85, and has a pedestal 821, a mounting member 822, a syringe 823, two slide guides 824, two holding members 825, a driving member 826, and a tray 827. ing. The mounting member 822 is shown in FIG.
As shown in (a), each slide guide 824 having a stopper (not shown) slidably supports the base 821 in a vertical direction, and is urged upward by a spring 824a attached to a linear shaft of each slide guide 824. ing.

As shown in FIG. 12, the syringe 823 has a body 823a for accommodating a solder paste and a piston 823b, and is held by each holding member 825 with a discharge port 823c facing upward. The holding member 825 is attached to the side plate 828 fixed to the attachment member 822, has a V-groove plate having a V-groove and a holding arm, and positions the body 823a with the V-groove plate to hold the syringe 823. ing.

As shown in FIG. 12, the driving member 826 is supported by the supporting member 822, and presses the piston 823b of the syringe 823 to discharge the solder paste from the discharge port 823c.
The driving member 826 is a member configured in the same manner as the first elevating stage 712, and includes a support plate 826a, a main body 826b, a screw shaft 826c, a slider 826d that moves in a vertical direction, and a pressing plate 826e.

The receiving tray 827 is provided with a discharge port 823c of the syringe 823.
This is a dish for storing the solder paste discharged from the container. Here, every time the solder paste discharged from the discharge port 823c of the syringe 823 supplies the solder to the main body 71 of the head unit 7, a scraper member 829 (see FIG. a), see FIG. 13).

The scraping portion 83 is a portion for scraping off excess solder protruding from the end face of the ferrule 713 after embedding the solder or adhering to the end face and wiping it off, as shown in FIGS.
As shown in FIG. 6, the support plate 831, two slide guides 83
2. It has a scraping roll 833 and a winding pulley 834.
The support plate 831 is vertically slidably supported by two slide guides 832 provided on the base 83a. The support plate 831 is urged upward by a predetermined spring force by a coil spring 835 mounted on the upper part of two side plates 83b provided on both sides of the base 83a. Support plate 831
The timing pulley 831a is rotatably supported on the front surface at the lower center, and the timing pulley 831a is
A drive motor 831b for rotating 1a is provided. The support plate 831 has an arm 836 attached to a lower part on the front surface.

As shown in FIG. 15, the arm 836 is rotatably attached to the support plate 831 at substantially the center, and a pinch roller 836a provided at the end on the timing pulley 831a side.
And a pin 836b for hooking a spring (not shown) for urging the arm 836 so that the pinch roller 836a contacts the timing pulley 831a. In addition, a detection piece 831c for detecting the ascending position of the support plate 831 is mounted on one side of the support plate 831 in cooperation with the photo sensor 837 mounted on the side plate 83b. Here, the upward movement position of the support plate 831 is regulated by a stopper cylinder 838 provided on the side plate 83b. The stopper cylinder 838 is
The shaft 8 whose tip abuts the regulating part 831d provided on the side of
38a.

As shown in FIG. 16, the slide guide 832 has a linear shaft 832a and a linear bush 832b attached to the support plate 831. Roll 833
As shown in FIG. 14, is a roll around which a scraping material 833a such as a non-woven fabric is wound, and is rotatably arranged on the upper left of the support plate 831. The scraping material 833a is sandwiched between the timing pulley 831a and the pinch roller 836a, and is wound at a constant speed.
It is wound up.

The take-up pulley 834 is disposed at the upper right portion of the support plate 831 and is rotated by a take-up motor 834a disposed on the back side to take up the surplus length of the cut-off material 833a. Here, in FIG. 14, reference numeral 839 is an air slide table. The monitor 84 checks the state of the solder attached to the optical fiber 714 of the head unit 7.
As shown in FIG. 9 and FIG. 10B, a C mounted on a mounting base 841 provided on the base 80 and provided on a support bracket 842 is provided.
It has a CD camera 843 and a lens barrel 844 attached to the camera 843. Here, a mirror 845 is provided on the moving stage 85 at a position facing the lens barrel 844 (see FIGS. 9 and 10B).
Is arranged. Further, a column 846 is provided on the mounting base 841, and a scraper member 829 is installed above the column 846. The scraper member 829 is a compact slide 829a
And a scraper 829b provided on the distal end side of an arm that expands and contracts by a compact slide 829a.

The moving stage 85 is a stage on which the cleaning section 81, the embedding section 82 and the cutting section 83 are placed and moved in the X-axis direction. Here, in FIGS.
Is a cable protection member for supplying power to the driving means of the moving stage 85. The bump forming apparatus 1 including the head unit 7 of the present invention is configured as described above. The operation of the head unit 7 will be described below together with the operation of the bump forming apparatus 1.

First, the power supply of the bump forming apparatus 1 causes the controller 9 to output a command signal to the preheating unit 6 to start preheating the substrate. Thereby, the preheating plate 6a
Preheating is started by the built-in heater. Here, the heater temperature is controlled by the controller 9 based on the measured value of the temperature sensor installed in the heater so as to maintain the set temperature.

Next, the substrate S is carried in from the carry-in entrance of the housing 2, and is carried to the preheating unit 6 by the conveyor 5. Then, the transported substrate S is positioned by the positioning pins provided on the conveyor 5, and then the preheated plate 6a
Rises into contact with the lower surface, and preheating is performed for 10 to 60 seconds. Next, the head unit 7 is moved to the X-axis robot 3.
Is moved to the supply unit 8 by the two Y-axis robots 4. At this time, the X-axis robot 3 and the Y-axis robot 4
Is controlled by the controller 9 such that the detection piece 723b is detected by the photo sensor 721a in the head unit 7 and the elevating plate 711, and thus the ferrule 713, is in the ascending position and does not operate unless it is confirmed that there is no obstacle to the movement. ing.

The head unit 7 is moved to the supply unit 8 and the ferrule 713 held by the lifting plate 711 is moved to the cleaning unit 8.
1, the solder amount data necessary to form the solder bumps is sent from the controller 9 to the supply unit 8.
Is forwarded to As a result, the head unit 7 and the supply unit 8 start operating in a preset order while being controlled by the controller 9.

That is, the ferrule 7 held on the lifting plate 711
When 13 stops immediately above the opening 81a of the cleaning unit 81, the cleaning unit 81 and the moving unit 72 of the head unit 7 start operating. In the head unit 7, the moving unit 72
The second elevating stage 722 is operated to move the elevating plate 7
11 is lowered, and the tip of the ferrule 713 is inserted into the opening 81a of the cleaning unit 81. At this time, the tip of the optical fiber 714 slightly protrudes from the tip of the ferrule 713.

Then, in the cleaning section 81, alcohol is injected from the injection nozzle 812 toward the tip of the ferrule 713, and the fiber hole and the optical fiber (both not shown) are cleaned. When the cleaning is completed, the second elevating stage 722
Raises the elevating plate 711 slightly, and pulls out the ferrule 713 from the opening 71a. Next, pressurized air is ejected from the air nozzle 811 of the cleaning unit 81 toward the tip of the ferrule 713, and alcohol remaining around is blown off, and the cleaning of the ferrule 713 is completed. When the cleaning is completed, the second elevating stage 722 raises the elevating plate 711 to the original height.

Next, embedding of solder into a fiber hole (not shown) of the ferrule 713 is executed as follows. First, the moving stage 85 is moved in the X-axis direction, and the embedding part 82 is moved to just below the ferrule 713 held by the elevating plate 711 and stopped. Next, the driving member 82 of the embedded portion 82
6, the piston 823b is pressed by the pressing plate 826e, and the solder paste is slightly pushed out from the discharge port 823c. Thereafter, the first lifting stage 712 of the head unit 7 operates to raise the optical fiber 714 to form a space of a predetermined size in the fiber hole of the ferrule 713.

Next, the second elevating stage 722 of the head unit 7 operates to lower the elevating plate 711, and press the end face of the ferrule 713 held on the extruded solder paste to insert the ferrule 713 into the fiber hole. Embed solder paste. When the embedding of the solder paste is completed, the second elevating stage 722 raises the elevating plate 711 to its original height and stops. At this time, the ferrule 713 has extra solder paste attached to the end face in addition to the fiber hole.

Thereafter, the cut-off portion 83 starts to operate, and the excess solder paste adhered to the end face of the ferrule 713 is wiped off as follows. First, the moving stage 85 is moved in the X-axis direction until the cutting roller 833 of the cutting section 83 is located immediately below the ferrule 713. Next, the second elevating stage 722 is operated to lower the elevating plate 711, and press the held end surface of the ferrule 713 against the cutoff material 833a. In this state, the moving stage 85
Is further moved slightly in the X-axis direction, and excess solder paste attached to the end surface of the ferrule 713 is wiped off with a scraping material 833a. When the scraping is completed, the second lifting stage 722 raises the lifting plate 711 to the original height and stops.

Next, in the head unit 7, the first elevating stage 712 is operated, and the slider 712d is slightly lowered slightly more than the amount corresponding to the amount of the solder paste embedded in the fiber hole of the ferrule 713. As a result, the optical fiber 714 fixed to the fixing plate 716 by the holding plate 717 descends and is pushed out from the end face of the ferrule 713 by about 0.02 mm. Along with this, the solder paste embedded in the fiber hole by the optical fiber
It is extruded while attached to 714. The extruded solder paste is photographed by the CCD camera 843 of the monitor unit 84, and the presence or absence of the solder paste, the amount of solder attached, and the like are checked. If the adhesion state is good, the process proceeds to the next step. If the adhesion state is bad, the process returns to the step of cleaning the tip of the ferrule 713, and the steps of embedding and scraping are repeated.

When the state of adhesion of the solder paste adhered to the optical fiber 714 is good, the solder paste is
The head unit 7 is moved to the substrate S by the X-axis robot 3 and the Y-axis robot 4 while being pushed out to the end face of the 713. Then, the elevating plate 711 is moved down by the second elevating stage 722, and a predetermined amount of solder paste adhered to the optical fiber 714 is adhered on a copper pad (not shown) of the substrate S. The solder light is melted by the heating light sent through to form minute solder bumps.

At this time, when the lifting plate 711 descends, first, the solder paste attached to the tip of the optical fiber comes into contact with the copper pad. Further, when the elevating plate 711 is further lowered, the solder paste is appropriately crushed so as not to be divided and securely adheres to the copper pad, and a drag force equivalent to a contact pressure acts on the optical fiber 714 via the crushed solder paste. . Then
Since the lifting plate 711 is supported by the moving portion 72 with a spring force of about several grams by the constant tension spring 724 and the tension spring 727, the lifting plate 711 is slightly lifted by the slider 715 being guided by the guide member 723 due to the reaction force. I do.

The vertical relative position of the guide member 723 and the vertical plate 711 changes as the vertical plate 711 moves up. The vertical distance is calculated from the distance signal output from the sensor 73 to the controller 9. Is done. Then, the controller 9 raises the head unit 7 by the second lifting stage 722 by an amount obtained by adding an arbitrary offset distance to the calculated relative distance, and removes the optical fiber 714 and the solder paste adhered on the copper pad of the substrate S. A gap is formed between them.

Here, the offset distance is such that when the solder paste adhered to the substrate S from the optical fiber 714 is heated and melted to form a solder bump, the molten solder interferes with the tip of the optical fiber 714, The distance is set so that the shape of the formed solder bump is not distorted and the solder is sufficiently melted by the heating light from the LD module 725 emitted from the optical fiber.

With the gaps thus formed, the solder is sufficiently melted by the heating light from the LD module 725 to form fine solder bumps on the copper pads of the substrate S. As described above, since the substrate S is preliminarily heated by the preheating unit 6, the solder can be quickly melted even with weak light. As described above, when forming the solder bumps on the substrate S, the head unit 7 of the present invention detects the relative distance between the elevating plate 711 and the moving unit 72 with the sensor 73 while maintaining the desired distance on the substrate S. Fine solder bumps having an appropriate shape can be formed at locations.

The substrate S on which the formation of the solder bumps has been completed as described above is conveyed to the carry-out port by the conveyor 5 and discharged, and a new substrate S is carried in from the carry-in port. The bump forming operation is repeated. Here, as described above, the head unit 7 adjusts the amount of insertion of the optical fiber 714 into the fiber hole of the ferrule 713 as appropriate, so that the solder embedded in the space formed by the fiber hole and the optical fiber 714 is formed. Can be set to a desired amount. Therefore, when the amount of solder of the solder bumps formed on the substrate S is small, it is possible to add a desired amount of solder to the solder bumps.

In the above embodiment, the ferrule
713 describes the case of a single-core ferrule that holds a single-core optical fiber, but if a solder bump of an appropriate shape can be formed stably, even if a multi-core ferrule for a multi-core connector is used. It goes without saying that it is good. Further, in the above embodiment, the ferrule 713 is used as a die, and the optical fiber 714 is used as a punch, but an appropriate amount of solder is used using a die and a punch corresponding to the size of a desired solder bump. It may be attached to the substrate S.

Further, as the heating source, the solder may be heated by heating the die or punch by heat conduction, or non-contact heating may be performed by a laser or the like.

[0050]

According to the first aspect of the invention, when the solder is adhered to a desired position on the substrate to form minute solder bumps, the relative distance between the member holding the solder and the substrate is controlled with high precision. The present invention can provide a soldering head unit that can perform the above. According to the invention of claim 2, extremely fine solder bumps can be formed at desired positions.
At this time, the influence on the solder bumps already formed in the surroundings is small.

According to the third and fourth aspects of the present invention, the main body can be moved relative to the moving portion in a direction approaching the substrate. According to the fifth aspect of the present invention, it is possible to prevent the solder adhered to the substrate from being crushed too much, and to avoid a situation in which the solder paste is divided and the formation of a good solder bump is prevented.

According to the sixth aspect of the present invention, the movable portion can be moved along the direction approaching the substrate while the main body is movably mounted along the direction approaching the substrate. According to the seventh aspect of the present invention, the vertical movement of the main body for forming the solder bumps can be performed precisely. In addition, it is possible to slightly adjust the force for pressing the solder to the substrate.

[Brief description of the drawings]

FIG. 1 is a front view (FIG. 1A) and a side view (FIG. 1B) of a solder bump forming apparatus to which a head unit for a soldering apparatus of the present invention is attached.

FIG. 2 is a plan view (FIG. 2A) and a rear view (FIG. 2B) of a solder bump forming apparatus to which a head unit for a soldering apparatus according to the present invention is attached.

FIG. 3 is a front view of a head unit for a soldering apparatus according to the present invention.

4 is a right side view of the head unit for a soldering apparatus of FIG. 3;

FIG. 5 is a right side view partially showing a cross section of the head unit for the soldering apparatus of FIG. 4;

FIG. 6 is a sectional view taken along the line VI-VI of FIG. 5;

FIG. 7 is a left side view of the head unit for a soldering apparatus of FIG. 3;

FIG. 8 is a front view showing a solder supply unit provided in the solder bump forming apparatus.

FIG. 9 is a plan view of the supply unit of FIG. 8;

10 is a side view (FIG. 10 (a)) showing a buried part of solder and a monitor part for monitoring the state of adhesion of the solder provided in the supply unit of FIG. (FIG. 10B).

FIG. 11 is an enlarged view in which a main part of a cleaning unit provided in the supply unit of FIG. 8 is enlarged.

FIG. 12 is a rear view of a solder embedding portion provided in the supply unit of FIG. 8;

FIG. 13 is an enlarged view of a tip end side of a syringe provided in a solder embedding portion provided in the supply unit of FIG. 8;

FIG. 14 is a front view showing a cutoff portion of the solder provided in the supply unit of FIG. 8;

FIG. 15 is a plan view showing a cross section of the frayed portion in FIG.

FIG. 16 is a side view showing a cross section of the frayed portion in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solder bump forming apparatus 2 Housing 3 X-axis robot 4 Y-axis robot 5 Conveyor 6 Preheating unit 7 Head unit for soldering device 71 Main unit 711 Holding member 712 First elevating stage 713 Ferrule 714 Optical fiber 72 Moving unit 722 Second elevating stage 723 Guide member 724 Constant tension spring 725 Laser diode module 728 Side plate 728a Reel 73 Sensor 8 Supply unit 80 Base 81 Washing part 82 Embedding part 83 Cutting part 84 Monitoring part 85 Moving stage

Claims (7)

[Claims] 1. A solder device head unit (7) for forming fine solder bumps by adhering fine solder to a desired position on a substrate, wherein the die is removably inserted into a through-hole provided in the die. Holding member for holding the punch and the die (71)
(1) a main body (71) for attaching a small amount of solder filled in the through-hole to the substrate; the holding member is movably attached along a direction approaching the substrate; A moving part (72) movable in a direction approaching the substrate, and a sensor (73) for detecting a relative distance between the main body part and the moving part in a direction approaching the substrate. Head unit. 2. An optical fiber (7) in which the die is a ferrule (713) and the punch is connected to a heating light source (725).
14. The head unit for a soldering device according to claim 1, wherein 3. The main body (71) has a solder extruding means (712) movable along a direction approaching the substrate, and the relative position between the punch and the die is moved by the solder extruding means. 2. The head unit for a soldering device according to claim 1, wherein 4. The holding member (711) includes a guide member (7
Attached to the moving part (72) via 23),
The head unit for a soldering device according to claim 1. 5. The moving member (711), wherein the holding member (711) is provided.
The head unit for a soldering device according to any one of claims 1 to 4, wherein the head unit is elastically suspended by a spring body (724) provided in (2). 6. The moving section (72) includes a lifting stage (72).
2. The head unit for a soldering device according to claim 1, comprising: (2). 7. After lowering the main body (71) to allow the solder to adhere to the substrate, the main body (71) is moved by a distance that takes into account the relative distance between the main body and the moving part (72) measured by a sensor (73). 2. A soldering method using a head unit for a soldering device according to claim 1, wherein a gap is formed between the solder attached to the substrate and the main body by raising a moving unit.