JP2004253769A - Process and apparatus for manufacturing solder bump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process and an apparatus for manufacturing a solder bump providing a semiconductor component or a substrate having high reliability in which a solder ball mounted on a semiconductor mounting face is prevented from being broken away, and the solder ball is prevented from being poorly disposed, in the semiconductor component or the substrate of a BGA type. <P>SOLUTION: The process for manufacturing the solder bump in which the solder ball is mounted on an electrode of the semiconductor component or the substrate, includes a process for forming a fixing body having the designated temporary fixing force on the electrode, and a process for mounting the solder ball on the electrode through the fixing body. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to the technical field of forming solder bumps on electrodes of a BGA (Ball Grid Array) type semiconductor component or substrate.

  2. Description of the Related Art In recent years, as mobile terminals and notebook personal computers have become faster, more sophisticated, lighter, smaller and thinner, semiconductor components constituting a CPU incorporated therein and substrates on which the semiconductor components are mounted have been developed. Are required to have contradictory performances such as miniaturization and thinning and an increase in the number of connection terminals. In response to the demand, there is a BGA type semiconductor component or substrate shown in FIG. 10A and 10B show a CPU including a substrate 7 and a semiconductor component 8 mounted on the substrate 7. FIG. 10A is a partially enlarged front view of the CPU, and FIG. FIG. 10C is a view showing a state where the semiconductor component 8 is mounted on the substrate 7.

  As shown in FIG. 10 (a), the substrate 7 has a thin plate-shaped substrate main body 71 and, as shown in FIG. 10 (b), a predetermined area on an electrode area F set at the center thereof, as shown in FIG. 10 (b). Of electrodes 72 formed in the above-mentioned arrangement pattern. As shown in FIG. 10A, the semiconductor component 8 has electrodes 81 formed on the lower surface thereof in the same arrangement pattern as the arrangement pattern of the electrodes 72. The electrodes 81 are electrically connected via the solder bumps 73.

  The BGA type semiconductor component 8 or the substrate 7 is supplied to the market in a form in which solder bumps 73 are formed on the electrodes 81 of the semiconductor component 8 and then connected to the substrate 7 later, as shown in FIG. In some cases, the solder bumps 73 are formed on the electrodes 72 of the substrate 7 and supplied to the market, and then connected to the semiconductor component 8 later. In the following description, the latter case will be described as an example.

  As a method of forming the solder bumps 73, there are a solder paste method in which a solder paste is printed on the electrodes 72, a solder ball method in which solder balls are mounted on the electrodes 72, and a film forming method in which solder is plated or vapor-deposited. As shown in FIG. 10B, the arrangement pitch P of the electrodes 72 is reduced due to the increase in the number of connection terminals of the semiconductor component 8 and the miniaturization, and accordingly, the size of the solder bump 73 of the semiconductor component 8 is also reduced. It tends to be. Therefore, when forming the small solder bumps 73, the solder bumps 73 can be arranged at an accurate pitch P by directly mounting the solder balls on the electrodes 72, and the solder bumps corresponding to the size of the solder bumps 73 can be formed. By using a ball, a solder bump 73 having a predetermined size can be easily obtained. In addition, a solder ball method having high productivity is often used.

  Conventionally, according to the solder ball method, the solder bump 73 is formed by printing a solder paste or a flux on at least a surface 721 of the electrode 72 on which the semiconductor component 8 is mounted (hereinafter, referred to as a semiconductor mounting surface); Alternatively, it is manufactured through a solder ball mounting step of mounting solder balls on the semiconductor mounting surface 721 on which the flux is printed, and a solder ball heating step of heating, melting and fixing the solder balls to the semiconductor mounting surface 721. .

  As an example of a method for mounting solder balls on the semiconductor mounting surface 721 in the solder ball mounting step, a solder ball is suctioned by a suction head using a negative pressure as described in Japanese Patent Application Laid-Open No. H11-150300 and the semiconductor balls are mounted on the semiconductor mounting surface 721. There is a suction method to transfer and load. However, in the suction method, there is a problem that the solder ball is deformed by the suction force of the suction head, but there is a problem that mounting failure occurs due to poor separability between the suction head and the solder ball. Further, the solder balls are charged by the air flow at the time of suction and take on an electromagnetic force, and due to the electromagnetic force, an aggregate of solder balls in a dumped state is mounted on the semiconductor mounting surface 721 or an excess solder ball ( There is a problem that extra balls (so-called extra balls) adhere to the surface of the substrate 7, and this problem has become remarkable especially as the diameter of the solder ball is reduced.

  As a method for solving such a problem of the suction method, a metal mask having a positioning opening corresponding to the arrangement pattern of the electrodes 72 is used, and solder balls are transferred to the positioning opening to place the solder balls on the semiconductor mounting surface 721. There is a transfer method to be mounted. Here, the transfer is an operation of inserting the solder ball into the positioning opening by moving the solder ball supplied on the metal mask with a brush, a brush or a squeegee, or swinging the solder ball supplied on the metal mask. And inserting a solder ball into the positioning opening.

  Patent Document 2 below discloses an example of a method of manufacturing the solder bump 73 in which the solder ball 74 is mounted on the semiconductor mounting surface 721 by a transfer method and the solder bump 73 is formed. As shown in FIG. 11, a method of manufacturing a solder bump 73 described in Patent Document 2 below includes a step of applying a flux 79 to a semiconductor mounting surface 721 (FIG. 11A), a process of applying a flux to the semiconductor mounting surface 721 and a positioning opening. The step of aligning the portion 923 in the plane direction and placing the metal mask 92 on the substrate 7 (FIG. 11B) and the step of mounting the solder balls 74 through the positioning openings 923 of the metal mask 92 (FIG. 11 ( c)), a step of removing the metal mask 92 (FIG. 11D), and a step of heating and fixing the solder balls 74 to the semiconductor mounting surface 721 (FIG. 11E).

According to such a transfer method, it is possible to prevent the above-described problem of the suction method. That is, in the transfer method, since an excessive force is not applied to the solder ball 74, the deformation of the solder ball 74 can be prevented. Since the mounting of the solder ball 74 is performed by the action of gravity, the mounting failure due to the suction can be eliminated. Further, even when the solder balls 74 are charged by the transfer, the aggregate of the solder balls 74 in the dumped state due to the restriction of the size of the positioning opening 923 is not mounted on the semiconductor mounting surface 721, and in addition, the semiconductor mounting surface 721 is not mounted. Since the surface of the substrate 7 is shielded by the metal mask 92, no surplus solder balls adhere.
JP 2001-223234 A JP 2001-156092 A

  However, according to the transfer method described above, the state after the solder balls 74 described with reference to FIG. 11C are mounted, as shown in FIG. 6A, the solder balls 74 mounted on the semiconductor mounting surface 721. Is temporarily fixed by the viscosity of the flux 79. Since the fixing force of the solder ball 74 due to the viscosity of the flux 79 is small, the solder ball 74 in contact with the side surface of the positioning opening 923 may come off the semiconductor mounting surface 721 when the metal mask 93 is removed. Further, the solder balls 74 may be detached from the semiconductor mounting surface 721 by an external force acting during the manufacturing process. Therefore, as shown by a symbol A in FIG. 11D, the solder balls 74 are not mounted on the semiconductor mounting surface 721, that is, a so-called mounting failure occurs, and there is a problem that the reliability of the substrate 7 is reduced. Furthermore, when the small solder balls 74 are mounted, the solder balls 74 easily adhere to the side surfaces of the positioning openings 923 due to the electromagnetic force due to charging, and the above-described problem of the mounting failure is remarkable.

  Accordingly, an object of the present invention is to prevent the solder balls 74 mounted on the semiconductor mounting surface 721 from being detached in the BGA type semiconductor component 8 or the substrate 7 and to reduce the occurrence of defective mounting of the solder balls 74 and to provide a highly reliable semiconductor. An object of the present invention is to provide a method and an apparatus for manufacturing a solder bump which can provide the component 8 or the substrate 7.

  The present inventors have conducted intensive research to solve the above-mentioned object, and formed a liquid or gel-like fixed body having a predetermined temporary fixing force, specifically, a surface tension or an adhesive force on the semiconductor mounting surface 721. However, it has been found that when the solder ball 74 is placed on the fixed body, the solder ball 74 is firmly fixed to the semiconductor mounting surface 721 via the fixed body. That is, as shown in FIG. 6B, for example, when the fixing body 75 having a predetermined surface tension is applied to the semiconductor mounting surface 721, the fixing body 75 uniformly wets the semiconductor mounting surface 721 due to its wettability. State. In such a state, the contact area between the fixed body 75 and the semiconductor mounting surface 721 becomes large, and the slipperiness of the fixed body 75 decreases. Thus, even if an external force acts on the fixed body 75, the position of the fixed body 75 on the semiconductor mounting surface 721 is maintained.

  When the solder balls 74 are placed on the fixing body 75 applied to the semiconductor mounting surface 721 in this way, as shown in FIG. 6 (c), the fixing body 75 makes the bottom of the solder balls 74 uniform due to its wettability. Then, the periphery of the fixing body 75 comes into close contact with and surrounds the bottom of the solder ball 74, and the contact area between the solder ball 74 and the fixing body 75 increases. The fixed body 75 that is in close contact with the surface of the solder ball 74 enters the minute unevenness on the surface of the solder ball 74 in a wedge shape to temporarily fix the solder ball 74. Accordingly, the solder balls 74 are temporarily fixed firmly to the semiconductor mounting surface 721 via the fixing body 75 for fixing the solder balls 74 while holding the position on the semiconductor mounting surface 721 as described above.

  The present inventors have diligently studied a method of firmly fixing a solder ball mounted on a semiconductor mounting surface to a semiconductor mounting surface based on the above-described fixing body, and have completed the present invention. That is, in the method of manufacturing a solder bump of the present invention, in the method of manufacturing a solder bump in which a solder ball is formed by mounting a solder ball on an electrode of a semiconductor component or a substrate, a fixed body having a predetermined temporary fixing force is attached to the electrode. The method is characterized in that the method includes a step of forming a fixed body to be formed and a step of mounting a solder ball on the electrode via the fixed body. Here, the term “temporary fixing force” specifically refers to a force for temporarily fixing the solder balls such that the solder balls can be separated, such as the adhesive force and surface tension of the fixed body. Preferably, after the solder ball mounting step, a fixing step of pressing, heating, or vibrating the solder balls is performed. More preferably, it is preferable that the method further includes an electrode cleaning step of cleaning the electrode before the fixed body applying step.

  Also, the solder bump manufacturing apparatus of the present invention is a solder bump manufacturing apparatus for forming a solder bump by mounting a solder ball on an electrode of a semiconductor component or a substrate, wherein a fixed body having a predetermined temporary fixing force is attached to the electrode. It is characterized by having a fixed body forming portion provided with a fixed body forming means to be formed, and a solder ball mounting portion for mounting the solder ball on the electrode. Further, it is desirable that the solder ball mounting portion has a pressing portion provided with at least one of a pressing unit for pressing the solder ball mounted on the electrode, a heating unit for heating, or a vibration unit for exciting. . More desirably, it is preferable to have a substrate pretreatment unit provided with a cleaning unit for cleaning the electrodes.

  According to the method of manufacturing a solder bump of the present invention, a fixed body having a predetermined temporary fixing force is formed on an electrode of a substrate, and a solder ball is mounted on the electrode via the fixed body. The solder ball is firmly fixed to the electrode by the action of the wetting of the fixed body to the electrode. Therefore, when the solder mask is removed in the solder ball mounting method of the transfer method, or the solder ball is prevented from separating from the electrode due to an external force acting during the manufacturing process, the solder bump can be reliably formed on the electrode. Thus, a highly reliable substrate or semiconductor component can be obtained.

  The method and apparatus for manufacturing a solder bump according to the present invention will be described below with reference to the drawings. FIG. 1 referred to here is a configuration diagram showing one embodiment of a solder bump manufacturing apparatus 5. FIG. 2 is a schematic configuration diagram of a solder ball mounting portion of the solder bump manufacturing apparatus of FIG. FIG. 3 is a view for explaining a main part of FIG. 2; FIG. 3A, which is a view taken in the direction of arrow B in FIG. FIG. 3B, which is a cross section of FIG. 3C, is an enlarged cross sectional view of the mask. FIG. 4 is a diagram illustrating a method of manufacturing solder bumps, including the operation of the solder bump manufacturing apparatus 5 of FIG. FIG. 5 is a diagram illustrating a detailed configuration of the solder bump manufacturing apparatus of FIG. The target substrate in the embodiment described below is the same as the substrate 7 described above. Further, the fixed body used in the following embodiment will be described as an example in which the surface tension of a liquid or gel is applied as a temporary fixing force.

[Embodiment 1]
As shown in FIG. 1A, the solder bump manufacturing apparatus 5 of the present invention includes the fixed body 75, the fixed body forming section 2 for forming the fixed body on at least the semiconductor mounting surface 721 of the electrode 72, and the semiconductor mounting section. And a solder ball mounting portion 1 for mounting the solder balls 74 on the surface 721. Note that the fixed body forming section 2 and the solder ball mounting section 1 are connected to each other by a board transport section that transports the board 7. For the substrate transfer unit, a well-known transfer unit such as a belt conveyor or a robot can be used. Hereinafter, the fixed body forming section 2 and the solder ball mounting section 1 will be described in detail.

[Fixed body forming part]
As shown in FIG. 5 (a), the fixed body forming unit 2 is movable above the substrate 7 in a planar direction, and a dipping device for discharging a liquid fixed body 75 from the tip of a needle 211 provided below. 21. According to the fixed body forming unit 2, the dipping device 21 can be positioned on the semiconductor mounting surface 721, the fixed body 75 can be applied, and the liquid-shaped fixed body 75 can be formed on the semiconductor mounting surface 721. The form of the fixing body 75 is not limited to the above, and may be, for example, a layer or a film. Accordingly, the application of the fixing body 75 can be performed using, for example, a screen printing apparatus, a vapor deposition apparatus, or a spraying apparatus, which is a well-known film forming means.

[Solder ball mounting section]
As shown in FIG. 2 (a), the solder ball mounting unit 1 has a holder 11 for holding the posture of the substrate 7 horizontally with the semiconductor mounting surface facing upward, a holder 11 capable of moving up and down, and And a thin plate-shaped mask 12 having a positioning opening formed in accordance with an electrode arrangement pattern and facing the substrate 7 positioned at a predetermined height via a gap t. A mask moving means 13 for supporting the right end of the mask 12 while allowing the mask 12 to be separated from the substrate 7 in the horizontal direction, and a supply port 141 disposed above the right end of the mask 12. Supply means 14 for supplying solder balls 74 to the upper surface of the mask, transfer means 15 movable in the horizontal direction while being in contact with the upper surface of the mask 12, and a suction port 161 arranged above the left end of the mask 12 Above 12 And removal means 16 for sucking the solder balls 74, and the common base 10 to dispose the holder 11 and the moving means 13, and a robot for handling the substrate 7 (not shown).

  The holder 11 has a wall portion 113 erected to the left of the holder 11 in the figure, and a substrate insertion plate having a depth obtained by adding a predetermined dimension t to the thickness of the substrate 7 as shown in the figure, to which the substrate 7 can be mounted. A mounting recess 112, an opening 111a opened on the bottom surface of the substrate mounting recess 112, an opening 111b opening to the outside, a fluid passage 111 communicating the openings 111a and 111b, and a fluid passage in the opening 111b. There is provided a negative pressure generating means which is connected to 111 and generates a negative pressure. According to the holder 11, when the substrate 7 is mounted in the substrate insertion recess 112 and a negative pressure is generated by the negative pressure generating means, the substrate 7 is fixed to the bottom surface of the substrate insertion recess 112 with a predetermined strength. The posture of the substrate 7 can be held horizontally.

  The initial position of the holder 11 is the lower position shown in FIG. 2B, and when the holder 11 is raised from the initial position by the elevating table 19, the holder 11 is inserted into the substrate insertion concave portion 112 as shown in FIG. The substrate 7 is positioned at a predetermined height.

  As shown in FIG. 3A, the mask 12 includes a mask body 121 having a positioning opening 123 formed in accordance with the arrangement pattern of the electrodes 72, and a frame 122 on which the mask body 121 is stretched. 2 (a), the contact with the upper surface of the holder 11 is maintained through the frame portion 122.

  As shown in FIG. 3B, the positioning opening 123 has a circular upper opening slightly larger than the diameter of the solder ball 74, a circular lower opening larger than the upper opening, an upper opening and a lower opening. Is desirably formed into a tapered hole shape having inclined side surfaces connecting the two. If the positioning opening 123 is formed in a tapered shape, a larger gap can be formed between the inclined side surface and the solder ball 74, and the detachment of the solder ball 74 when removing the mask 12 can be prevented.

  By setting the right position shown in FIG. 2B as the initial position of the mask 12 and moving the mask 12 to the left by the mask moving means 13, the left end face of the mask 12 becomes as shown in FIG. The mask 12 is positioned in contact with the right side surface of the wall portion 113 of the holder 11, and the semiconductor mounting surface 721 and the positioning opening 123 of the mask 12 coincide with each other as shown in FIG. Further, since the upper surface of the substrate 7 mounted in the substrate mounting recess 112 and the upper surface of the holder 11 are separated by a predetermined distance t, as shown in FIG. , A constant gap t is formed.

  The mask 12 is preferably made of, for example, a resin selected from at least one of polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyamide, cellulose acetate, and polyester. If the mask 12 is made of resin, the charged solder balls 74 are less likely to adhere to the side surfaces of the positioning openings 123, so that mounting failure due to detachment of the solder balls 74 can be prevented. Furthermore, in the case of a high-cost metal mask, it takes time and effort to recycle the metal mask after use, such as cleaning for reuse, but the resin mask is inexpensive and can be disposable. Since the positioning opening 123 of the mask can be easily formed by mechanical or thermal processing such as laser processing or punching, it is extremely efficient in industrial production.

  As shown in FIG. 2A, the transfer means 15 uses a squeegee, a brush or a brush to transfer the solder balls 74 supplied from the supply port 141 to the upper surface of the right end of the mask 12 to the left end. It is moved and inserted into the positioning opening 123 of the mask 12. The transfer means 15 is not limited to the configuration described above. For example, the mask 12 may be swung in the horizontal direction, or the mask 12 may be swung about an axis perpendicular to the paper surface to move the solder ball to the positioning opening 123. 74 may be inserted.

  In the solder bump manufacturing apparatus 5 having the above configuration, the fixing body 75 is formed on the semiconductor mounting surface 721, and the solder balls 74 are mounted on the semiconductor mounting surface 721 via the fixing body 75. Hereinafter, the operation of the solder bump manufacturing apparatus 5 will be described in detail with reference to FIG. 2, FIG. 4, and FIG.

[Fixed body coating step]
The fixed body forming part 2 positions the dispensing means 21 on the semiconductor mounting surface 721 as shown in FIG. 5A, and fixes the fixed body to at least the semiconductor mounting surface 721 of the electrode 72 as shown in FIG. Apply 75. Thereafter, the substrate transporting unit transports the substrate 7 on which the fixed body 75 is formed to the solder ball mounting unit 1.
[Mask mounting process]
As shown in FIG. 2 (b), the solder ball mounting portion 1 has the semiconductor mounting surface 721 oriented horizontally upward with the holder 11 and the mask 12 at the initial position and the substrate mounting recess 112 exposed. The substrate 7 is inserted into the substrate insertion concave portion 112 by a robot, and a negative pressure is generated by a negative pressure generating means to fix the substrate 7 in the substrate insertion concave portion 112. Thereafter, as shown in FIG. 2A, the solder ball mounting unit 1 raises the holder 11 to a predetermined position, moves the mask 12 to the left, and as shown in FIG. The mask 12 is mounted above.

[Solder ball mounting process]
As shown in FIG. 2A, the solder ball mounting section 1 supplies the solder balls 74 to the upper surface of the right end of the mask 12 by the supply means 14, and transfers the supplied solder balls 74 to the left end by the transfer means 15. 4C, the solder ball 74 is inserted through the positioning opening 123, and the solder ball 74 is mounted on the semiconductor mounting surface 721 via the fixing body 75. On the other hand, the solder ball mounting section 1 collects the remaining solder balls 74 that are not inserted into the positioning openings 123 at the left end of the mask 12 by the transfer means 15 as shown in FIG. It is removed by means 16.
[Substrate removal process]
As shown in FIG. 2B, the solder ball mounting unit 1 returns the holder 11 to the initial position, returns the mask 12 to the initial position, and exposes the substrate 7 on which the solder balls 74 are mounted. . Thereafter, the solder ball mounting unit 1 turns off the negative pressure of the negative pressure generating means, and removes the substrate 7 from the substrate insertion recess 112 by a robot.

  Thereafter, for example, the fixing body 75 is heated or evaporated in a reduced-pressure atmosphere, and the solder ball 74 mounted on the semiconductor mounting surface 721 is heated and melted, and the melted solder ball 74 is cooled, as shown in FIG. Thus, the solder bump 73 is formed on the semiconductor mounting surface 721.

  As described above, if the fixed body 75 having a predetermined temporary fixing force is formed on the semiconductor mounting surface 721 and the solder ball 74 is placed on the fixed body 75, the solder ball 74 is connected to the semiconductor ball via the fixed body 75. Since the solder balls 74 are firmly fixed to the mounting surface 721, the solder balls 74 can be prevented from detaching from the semiconductor mounting surface 721 due to an external force acting when the mask 12 is removed or during a manufacturing process. It is possible to form it reliably.

[Embodiment 2]
Another embodiment of the present invention will be described with reference to FIGS. 1, 3, 6, 7 and 8. FIG. 7 referred to here is a configuration diagram of a solder ball mounting portion of the solder bump manufacturing apparatus 5 'of the present embodiment. FIG. 8 is a diagram illustrating a method of manufacturing solder bumps, including the operation of the solder bump manufacturing apparatus 5 ′ of FIG. 7 and 8, the same components as those of the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

  As shown in FIG. 1, a solder bump manufacturing apparatus 5 'of the present embodiment includes a fixed body forming section 2 and a solder ball mounting section 1' which are basically the same as the solder bump manufacturing apparatus 5, and includes a semiconductor device. The solder ball mounting portion 1 'is devised to further firmly fix the mounting surface 721 and the solder balls 74. The configuration of the solder ball mounting portion 1 'will be described in detail below.

  As shown in FIG. 7A, the solder ball mounting unit 1 'includes a holder 11, a lifting table 19, a mask 12', a mask moving unit 13, and a supplying unit 14 similar to the solder ball mounting unit 1. , A transfer means 15, a removing means 16, a common base 10, and a robot (not shown), and further has a surface 171a facing the mask 12 'and is disposed above the mask 12'. The fixing portion 17 includes a pressing body 171 and lifting / lowering pressing means 172 that holds the pressing body 171 and allows one surface 171a of the 17 to be vertically detachable with respect to the upper surface of the mask 12 ′.

  One surface (hereinafter, referred to as a contact surface) 171a of the pressing body 171 facing the mask 12 'has a size including at least the electrode area F of the substrate 7, as shown in FIG. 7B. . The pressing body 171 is disposed above the electrode area F of the substrate 7 inserted into the substrate insertion recess 112 via a mask 12 ′.

  Here, the thickness st of the mask body 121 ′ of the mask 12 ′ is set as shown in Expression 1 so that the top of the solder ball 74 can be seen from the upper surface of the mask 12 ′ as shown in FIG. I do.

ここで ｄ：半田球の直径

Where d: diameter of solder ball

  When the initial position of the pressing body 171 is set to the upper position shown in FIG. 7B and the pressing body 171 is lowered from the initial position by the lifting / lowering pressing means 172, as shown in FIG. 8D, the contact surface 171a becomes Abuts on the top of the solder ball 74 exposed from the upper surface of the mask 12 '. Here, when the solder balls 74 are pressed by the vertical pressing means 172 with an appropriate pressing force, the solder balls 74 are fixed without damaging the semiconductor mounting surface 721 of the electrode 72 as shown in FIG. The contact area between the solder ball 74 and the fixed body 75 is further increased by being buried deeper in the body 75. Thus, the solder balls 74 can be more firmly fixed to the semiconductor mounting surface 721 via the fixing body 75.

  Further, the fixing portion 17 may include a heating means for heating the solder balls 74. The heating unit can be configured by appropriately disposing a well-known heating member such as a metal heater or a ceramic heater on the pressing body 171. By heating the solder ball 74 at an appropriate temperature not higher than the boiling point of the fixing member 75 and not higher than the melting point of the solder ball 74 while the pressing member 171 is in contact with the solder ball 74, the fixing member 75 is heated by the heat transmitted through the solder ball 74. When activated, the wettability increases, the contact area between the solder ball 74 and the fixing body 75 increases, and the solder ball 74 can be firmly fixed to the semiconductor mounting surface 721 via the fixing body 75.

  Further, the fixing portion 17 may include a vibrating means for vibrating the solder balls 74. The vibrating means can be configured by appropriately arranging a well-known vibrating member such as a vibrator or an ultrasonic generator on the pressing body 171. When vibration is applied to the solder ball 74 while the pressing body 171 is in contact with the solder ball 74, the wettability of the fixed body 75 is increased by the vibration propagated through the solder ball 74, and the contact area between the solder ball 74 and the fixed body 75 increases. The solder balls 74 can be firmly fixed to the semiconductor mounting surface 721 via the fixing body 75.

  8D, when the thickness of the mask 12 'is larger than the diameter of the solder ball 74, the mask 12' is formed so as to correspond to the positioning opening 123 and be insertable into the positioning opening 123. As shown in FIG. In addition, a protrusion 171b that can contact the top of the solder ball 74 may be provided on the pressing body 171 so that the protrusion 171b can selectively contact the solder ball 74 inserted into the positioning opening 123.

  The pressing body 171 with the projection can be obtained, for example, by forming the projection 171b on the surface of a metal plate serving as a base of the pressing body 171 by an electroforming method. Further, it can be obtained by using a thin plate in which at least two different metals are stacked in two or more layers, for example, two layers of Ti and a 42% Ni alloy, and etching either one of the metals to form the projections 171b. . Furthermore, if a thin plate having a metal layer on at least the front surface and the back surface and having a barrier layer formed between the metal layers as an etching stopper is used, and either the front surface or the back surface is etched to form the projection 171b, The pressing body 171 with a projection can be obtained.

  The solder bump manufacturing apparatus 5 ′ having the above configuration forms the fixed body 75 on the semiconductor mounting surface 721, mounts the solder ball 74 on the fixed body 75, and further presses, heats, or vibrates the solder ball 74. Things. Hereinafter, the operation of the solder bump manufacturing apparatus 5 'will be described in detail.

The solder bump manufacturing apparatus 5 ′ applies the fixing body 75 to the semiconductor mounting surface 721 in the same manner as described above (FIG. 8A, fixing body applying step), and mounts the mask 12 ′ above the substrate 7 ( 8B, the mask mounting step), the solder ball 74 is inserted into the positioning opening 123 of the mask 12 ′ (FIG. 8C, the solder ball mounting step), and the solder ball 74 is placed on the fixed body 75. State.
[Fixing step]
The solder ball mounting unit 1 'lowers the pressing body 171 from the initial position shown in FIG. 7B by the lifting / lowering pressing means 172 as shown in FIG. 7A, and as shown in FIG. The contact surface 171a is brought into contact with the top of the solder ball 74, and the solder ball 74 is pressed with a predetermined pressing force. Thereafter, the solder ball mounting section 1 'raises the pressing body 171 and returns it to the initial position.

  The solder bump manufacturing apparatus 5 'removes the substrate 7 in the same manner as described above (FIG. 8E, substrate removing step). Thereafter, the fixing body 75 is heated or evaporated in a reduced-pressure atmosphere, the solder ball 74 is heated and melted, and the melted solder ball 74 is cooled, as shown in FIG. The solder bump 73 will be formed.

  As described above, by pressing, heating, or vibrating the solder ball 74 placed on the fixing body 75, the solder ball 74 and the fixing body 75 are brought into a closer state, and further, the solder ball 74 is placed on the semiconductor mounting surface. 721 will be firmly fixed.

Still another embodiment of the solder bump manufacturing apparatus of the present invention will be described with reference to FIGS.
As shown in FIG. 9A, the solder bump manufacturing apparatus may include a table on which the substrate 7 is placed, and a fixed body applying section 2 and a solder ball mounting section 1 disposed on the outer periphery of the table. . According to the solder bump manufacturing apparatus 5a, the substrate 7 is placed on the table, the fixed body applying unit 2 moves in the table direction to apply the fixed body 75, and the solder ball mounting unit 1 moves in the table direction. The solder balls 74 are mounted on the fixed body 75.

  Further, as shown in FIG. 9 (b), the solder bump manufacturing apparatus 5b includes a substrate pre-processing unit 3 disposed upstream of the fixing body forming unit 2 and cleaning the semiconductor mounting surface 721 of the electrode 72. Is desirable. As shown in FIG. 5 (b), the substrate pretreatment unit 3 is a cleaning unit 51 composed of a wet blasting device that makes the upper part of the substrate 7 movable in a planar direction and irradiates the fine particles 511 mixed with the liquid 512 downward. have. According to the substrate pretreatment unit 3, in the electrode cleaning step before the fixing body applying step, the semiconductor mounting surface 721 is irradiated with the fine particles 511 to remove oxides and dirt generated on the semiconductor mounting surface 721. In addition, the semiconductor mounting surface 721 can be cleaned. If the semiconductor mounting surface 721 is cleaned, the wettability of the fixing body 75 with respect to the semiconductor mounting surface 721 is further increased, and the fixing body 75 flows uniformly on the semiconductor mounting surface 721 and is widely distributed on the semiconductor mounting surface 721. Become. Thus, the adhesion between the fixing body 75 and the semiconductor mounting surface 721 is improved, and the solder balls 74 are firmly fixed to the semiconductor mounting surface 721.

  Also, if the semiconductor mounting surface 721 is cleaned, the wettability of the heated and melted solder balls 74 to the semiconductor mounting surface 721 increases, and the molten solder balls 74 flow uniformly on the semiconductor mounting surface 721, It will be uniformly distributed on the mounting surface 721. Accordingly, it is possible to form the solder bump 73 with few defects such as bridges and voids. The cleaning unit 51 is not limited to the above description, and may be, for example, an ion irradiator, a plasma irradiator, a UV irradiator, or an ion irradiator, a plasma irradiator, or a UV irradiator that irradiates ions, plasma, UV, or a high energy beam to clean the semiconductor mounting surface 721. You may comprise using a high energy beam irradiation apparatus etc.

  Further, as shown in FIG. 9C, the solder bump manufacturing apparatus 5c may have a solder ball heating unit 4 disposed downstream of the solder ball mounting means 1 for heating and melting the solder balls 74. Is desirable. As shown in FIG. 5C, the solder ball heating unit 4 has a heating means 41 which is provided above the substrate 7 and is composed of an infrared heating device for irradiating infrared rays 411 downward. The solder ball 74 mounted on the 721 is irradiated with infrared rays 411 to heat and melt the solder ball 74. The heating unit 41 is not limited to the above description, and may be configured using a hot air irradiation device or a high energy beam irradiation device that irradiates the solder balls 74 with hot air or a high energy beam.

  Further, as shown in FIG. 9 (d), if the solder bump manufacturing apparatus 5d includes the substrate pre-processing unit 3, the fixed body applying unit 2, the solder ball mounting unit 1, and the solder ball heating unit 4, the electrode A series of processes for forming the solder bumps 73 on 72 can be performed continuously, which is efficient and desirable in industrial production.

  In addition, the solder bump manufacturing apparatuses 5 to 5c are provided with a housing (not shown) in which the substrate pretreatment unit 3, the fixed body forming unit 2, the solder ball mounting unit 1, or the solder ball heating unit 4 is disposed in an internal space. And a vacuum generating means (not shown) connected to the housing to make the internal space of the housing a vacuum or a gas generating means for generating an inert gas such as N, Ar, or He. desirable. With such solder bump manufacturing apparatuses 5 to 5c, the surroundings of the substrate 7 and the solder balls 74 can be made vacuum or an inert atmosphere to prevent oxidation and dirt on the surfaces of the semiconductor mounting surface 721 and the solder balls 74. The surface 721 and the surfaces of the solder balls 74 can be kept clean.

  An example of a selection method based on the surface tension of the fixed body 75 used in the present invention will be described. As the fixing body 75, one having a low surface tension and a high wettability to the solder balls 74 and the semiconductor mounting surface 721 is selected. Examples of the fixed body 75 include isopropyl alcohol, a large number of alcohol-based liquids such as 2-octanol, and liquids containing, for example, a cationic, anionic, amphoteric or nonionic active ingredient, flux, A non-cleaning flux, a non-cleaning flux containing no rosin (pine resin), or a gel is selected.

  Note that it is desirable to select the fixing body 75 having a boiling point equal to or lower than the melting point of the solder ball 74. If such a fixed body 75 is selected, the fixed body 75 is evaporated at the same time by the heat for heating the solder balls 74, so that it is possible to efficiently form the solder bumps 73 without the trouble of removing the fixed body 75. Become.

  The present invention can be applied not only to a spherical body such as a conductive ball, but also to a case where irregular shapes such as powders and granules are arranged on a work in a predetermined pattern.

It is a schematic structure figure showing an example of the manufacturing device of the solder bump of the present invention. FIG. 2 is a diagram illustrating a configuration of a solder ball mounting unit in FIG. 1. FIG. 10 is a diagram illustrating details of a solder ball mounting unit in FIG. 9. FIG. 2 is a process diagram illustrating an operation of the mounting device of FIG. 1. FIG. 10 is a diagram illustrating a configuration of a fixed body application unit in FIG. 1, a substrate pretreatment unit and a solder ball heating unit in FIG. FIG. 4 is a diagram illustrating a state of a solder ball mounted on an electrode. FIG. 2 is a configuration diagram illustrating another embodiment of the solder ball mounting unit of FIG. 1. FIG. 8 is a process chart for explaining the operation of the solder ball mounting unit in FIG. 7. It is a schematic structure figure showing other examples of a manufacturing device of a solder bump of the present invention. FIG. 3 is a diagram illustrating a configuration of a substrate on which solder balls are mounted. It is a figure explaining the mounting method of the conventional solder ball.

Explanation of reference numerals

1: Solder ball mounting part, 11: Holder, 12: Mask, 13: Mask moving means 14: Supply means, 15: Transfer means, 16: Removal means 17: Fixing section, 19: Elevating table 2: Fixing body application section 3 : Board pre-processing unit 4: solder ball heating unit 5: solder bump manufacturing device 7: board, 71: board body, 72: electrode, 73: connection terminal, 74: solder ball
75: fixed body 8: semiconductor component, 81: electrode

Claims (6)

  In a method for manufacturing a solder bump in which a solder ball is formed by mounting a solder ball on an electrode of a semiconductor component or a substrate, a fixed body forming step of forming a fixed body having a predetermined temporary fixing force on the electrode; A solder ball mounting step of mounting a solder ball on the electrode via a solder ball.   2. The method according to claim 1, further comprising, after the solder ball mounting step, a fixing step of pressing, heating, or vibrating the solder balls.   3. The method of manufacturing a solder bump according to claim 1, further comprising an electrode cleaning step of cleaning the electrode before the fixed body forming step. 4.   In a solder bump manufacturing apparatus for forming a solder bump by mounting a solder ball on an electrode of a semiconductor component or a substrate, a fixed body forming means provided with a fixed body forming means for forming a fixed body having a predetermined temporary fixing force on the electrode And a solder ball mounting portion for mounting the solder ball on the electrode.   5. The solder bump manufacturing apparatus according to claim 4, wherein the solder ball mounting unit is at least one of a pressing unit that presses a solder ball mounted on the electrode, a heating unit that heats, and a vibration unit that vibrates. An apparatus for manufacturing a solder bump, comprising: a fixing portion having one of them.   The solder bump manufacturing apparatus according to claim 4, further comprising a substrate pre-processing unit including a cleaning unit that cleans the electrodes.

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