KR100740594B1 - Bump forming apparatus - Google Patents

Abstract

In the bump forming apparatus, productivity is improved without increasing the kind of the holding part of the holding tool which moves the chip. The bump forming apparatus 10 includes a tray loader portion 12, a supply and receiving tray 14, and also a bump forming portion 20 having two bonding stages 24 and 26 for forming bumps, bumps A leveler portion 40 comprising a leveler stage 44 having two holding stages for uniformly adjusting height, and two bonding stages of the supply and accommodation tray 14-bump forming portion 20 to hold a chip ( And a chip collet conveyance section 60 for holding and moving between the two holding stage-feeding and receiving trays 14 of the leveler section 40.

Bump, Chip, Collet, Leveler, Stage, Tray, Bonding, Carrying, Gripping, Pick & Place, Cycle Time, Semiconductor

Description

Bump Forming Apparatus {BUMP FORMING APPARATUS}

1 is a view showing the configuration of a bump forming apparatus in an embodiment according to the present invention,

2 is a view showing the components related to the bump forming portion in the embodiment according to the present invention,

FIG. 3 is a diagram showing an example of a sequence in which bump formation is efficiently performed using two bonding stages in an embodiment according to the present invention.

4 is a view showing a concept of uniformly adjusting the bump height,

5 is a view showing the components of the leveler portion in the embodiment according to the present invention,

6 is a diagram showing an example of a sequence for efficiently performing bump height matching using two holding stages of the leveler stage in the embodiment according to the present invention;

7 is a cross sectional view of a chip collet in an embodiment according to the invention,

8 is a view showing a part of the operation sequence of the bump forming apparatus in the embodiment according to the present invention,

FIG. 9 is a view for explaining the time variation regarding the position of the chip collet and the pick and place (positioning arrangement) in the embodiment according to the present invention.

<Description of the code>

2, 3, 4, 6: chip 5: bonding pad

7, 9: bump 8: wire

10 bump forming device 12 tray loader

14: supply and storage tray 15: supply tray

16: sub tray 17: storage tray

18: waiting position 20: bump forming portion

22: bonding head 24, 26: bonding stage

28: case stage 30: spool

32: wire clamper 34: capillary

36: torch 40: leveler part

42: leveler head 44: leveler stage

46: rotational watch mechanism 48: load cell

50: vertical movement mechanism 52, 54: holding stage

56: slider mechanism 58: guide table

59: up and down moving table 60: chip collet conveying unit

62: chip collet 64: Y moving mechanism

66: X moving mechanism 68, 70: collet head

80: control unit 82: load unload processing module

84: bump formation processing module 86: leveler processing module

88: return processing module

The present invention relates to a bump forming apparatus, and relates to a bump forming apparatus for forming a plurality of bumps having a uniform height on a chip.

Background Art A technique for forming a bumped chip by forming a plurality of bumps as electrode terminals on the surface of the chip, and connecting the circuit board or the like with one bonding through the plurality of bumps is widely known as face down bonding. As a method of forming a bump on the surface of a chip, there are a method of bonding a bump ball onto a bonding pad, a method of forming a solder layer on the bonding pad by solder plating, and spheroidizing by heating. It is also possible to use a bonding technique using a wire.

For example, Patent Document 1 describes that bump bonding with a wire is performed on an electrode of a semiconductor element by ultrasonic thermocompression. Here, bump bonding by wire is performed, and then leveling for correcting the bump to a predetermined height is also performed. Then, the chip is processed before or after processing using a holding tool between the supply tray of the chip, the bonding stage where bump bonding is performed, the leveling stage for uniformly adjusting the bump height, and the storage tray for accommodating the chip with uniform bump height. By holding, moving and conveying one after another while maintaining the subsequent chips, chips with uniform bumps are produced.

In patent document 1, the research which improves especially productivity of bump formation and leveling is made | formed. That is, using two bonding stages, one leveling stage, and a holding tool for carrying and conveying chips while having a total of three holding portions, one pre-processing holding tool and two post-processing holding tools, are used. have.

The reason there is not one holding tool for conveying chips is that the chips before bump formation (before processing) have flatness of the thickness nonuniformity at the thin film level, but after the bump formation (after processing) This is because bumps with a height of about 10 μm protrude from the surface of the chip, and therefore, research is required for the shape of the holding part to prevent the deformation of the bumps. In Patent Document 1, two post-machining holding tools are provided in order to increase productivity by reducing the waiting time of the leveling stage since there are two bonding stages and one leveling stage.

[Patent Document 1] Japanese Patent Application Laid-Open No. 2001-267353

According to the structure of patent document 1, productivity improves remarkably compared with the structure of one bonding stage and one leveling stage, and compared with using the holding tool which has two types of holding | maintenance parts even when the bonding stage is extended to two. Productivity is expected to improve.

However, the shape of the holding portion of the holding tool needs to be individually matched with each other to suit the size and shape of the chip to be held, which causes a cost increase when bump bonding a plurality of types of chips having different sizes or shapes. In addition, since two holding stages and one leveling stage use three holding portions separately, the sequence is likely to be complicated.

It is an object of the present invention to provide a bump forming apparatus capable of improving productivity without increasing the type of holding portion of the holding tool for carrying and moving chips.

A bump forming apparatus according to the present invention is a bump forming apparatus for forming a plurality of bumps having a uniform height on a chip, comprising: a supply tray for supplying a chip and a bump forming portion for forming a plurality of bumps on a chip; A bump stage having a bump stage, and when forming bumps on a chip in one bump stage, the other bump stage next waits for a chip to be bump-formed or a chip already formed with bumps; A leveler part that has a high level of fit, which has two or more leveler stages, and when one leveler stage evenly adjusts the height of the bumps, the other leveler stages next have the bumped chip or the heighted bumped chip. And a storage tray for storing chips having a uniform height of bumps And a chip collet conveying unit for exchanging and conveying chips using a chip collet between the supply tray, the bump forming unit, the leveler unit and the storage tray, and a control unit for controlling a cycle time of bump formation. Means for causing the chip collet to hold the first chip, moving the chip collet holding the first chip, positioning the bump collet in the bump stage on the side where bump formation is to be made, and the empty chip collet Means to move to the bump stage on which the bump formation is completed, and to move the chip collet catching the second chip and the level of the leveler part by moving the chip collet catching the second chip from there. Means for positioning on the leveler stage of the side, and the level of the side where the bump height matching has already been completed for the empty chip collet Means for moving to the stage, whereby the third chip is already uniform in height and catches the standby chip; and means for moving the chip collet holding the third chip and positioning and storing it in the storage tray. .

Further, in the bump forming apparatus according to the present invention, the cycle time required for bump formation per one bump stage and the height of the bump per one leveler stage are more uniform than the transfer cycle time starting from the supply tray to the storage tray. It is desirable to control the matching cycle time shortly.

Further, in the bump forming apparatus according to the present invention, the chip collet conveying unit has a grip shape for holding a bumpless chip that does not have a bump formed yet, and a chip holding collet for a bumpless chip and a bumped chip for which a bump is already formed. It is preferable to have a chip collet for bumped chips having a shape, and the controller selects a chip collet for use by the chip collet conveying unit according to the bumpless chip and the bumped chip.

Further, in the bump forming apparatus according to the present invention, the leveler portion is a slide leveler stage in which a plurality of leveler stages are arranged in the moving direction, and the leveler stage is pressed into a work area of the pressing mechanism by pressing the bump to an arbitrarily set height. It is desirable to have a leveler band for moving.

(The best form to carry out invention)

EMBODIMENT OF THE INVENTION Hereinafter, embodiment which concerns on this invention is described in detail using drawing. In the following description, bumps are formed by wire bonding using gold wires as bump forming apparatuses, and the bump heights are uniformly adjusted at the leveler portion. However, the material of the wires may be other than gold, for example, aluminum. The bump formation may be a method other than wire bonding, for example, a method of joining and forming a conductive microball on a chip. In addition, although the bonding stage of the bump formation part and the holding stage of the leveler part were made into two pieces, respectively, they are two or more, and the number does not matter. In addition, in the following description, the supply tray for supplying the chip and the storage tray for accommodating the chip having a uniform height of bumps are performed as one supply and the storage tray. You may make it.

1 is a diagram illustrating the configuration of the bump forming apparatus 10. The bump forming apparatus 10 is a device which forms a plurality of bumps on the surface of a semiconductor chip and uniformly adjusts the heights of the bumps in a predetermined range. A chip having a uniform height of bumps thereafter faces a circuit board or the like. Provided for down bonding. As a chip, an LSI chip or an electronic component having a size of about 1 mm square to several mm square or more than 10 mm square can be used. The bump is, for example, pressed and crushed by a gold ball having a diameter of about 10 μm. A shape can be used.

Therefore, the bump forming apparatus 10 supplies the tray loader part 12 which puts in or removes the tray which accommodates the sample before and behind bump formation, and the supply and storage tray which supplies the chip before operation, and accommodates the chip | tip with which the height became uniform. (14) is provided. In addition, the bump forming apparatus 10 includes a bump forming unit 20 for forming bumps by a method of wire bonding to a chip, a leveler unit 40 for uniformly matching the height of bumps formed on the chip, and holding and supplying the chip. The chip collet conveyance part 60 for carrying a tray 14, the bump formation part 20, the leveler part 40, and the supply and accommodation tray 14 for movement is provided. A control unit 80 is also provided to control the production of bumped chips having uniform height and uniformity in operation of these elements as a whole.

The tray loader 12 stacks up a plurality of supply trays 15 for aligning and arranging chips before the work, and also stacks up a plurality of storage trays 17 for aligning and storing bumped chips having a uniform height, It is a sample entrance part which has a function which moves each tray with progress of bump forming operation. The control is performed under the control of the load unload processing module 82 of the control unit 80.

Prior to the start of the operation in the tray loader section 12, only a plurality of supply trays 15 in which chips before the operation to which bumps are to be formed are stored are stored, and the storage tray 17 is not yet present. Then, the first feed tray from the stacked feed trays 15 is conveyed to a predetermined chip holding position by a belt conveying mechanism or the like and positioned to become a work supply and storage tray 14. This chip catching position is a start position where a chip is moved to the bump formation part 20 by the chip collet conveyance part 60 from here, and a terminal position where the bumped chip from which the height became uniform from the leveler part 40 is moved. Corresponding. Therefore, the tray at the chip holding position has both a function of aligning and arranging chips before the operation and a function of aligning and storing bumped chips having a uniform height, and in that sense, are referred to as supply and storage trays 14. .

When the work progresses and the height of the work supply and the storage tray 14 is filled with the bumped chips which are uniform, the belt is transported to the position of the storage tray 17 of the tray loader part 12 by the belt conveying mechanism or the like and stacked. . At that time, when waiting is necessary, the waiting position 18 can be waited once. In addition, since the feeding and receiving tray 14 generally eliminates the chips before the operation before it is filled with bumped chips having a uniform height, for this purpose, the sub tray 16, which is a preliminary feeding tray, is used as the original feeding and receiving tray 14. Wait behind the scenes. In this manner, as the bumps are formed, the respective trays in the tray loader 12 are moved efficiently.

The bump forming unit 20 is a work station having a function of forming a plurality of bumps on the chip surface under the control of the bump forming processing module 84 of the control unit 80. The bump forming portion 20 includes a bonding head 22 for performing wire bonding and two bonding stages 24 and 26. The two bonding stages 24 and 26 are work stages having a function of holding a chip for the bonding operation and are movable in the Y direction shown in FIG. The bonding head 22 is movable in the XY plane shown in FIG. 1 so that the bonding operation can be performed at any bonding stages 24 and 26, and also in the Z direction perpendicular to the XY plane. The two bonding stages are for waiting for a chip to form the next bump or a chip having bumps already formed in another bonding stage when the bonding operation is performed in one bonding stage.

2 is a diagram illustrating components of the bump forming unit 20. Although not a component of the bump forming unit 20, the chip 2, which is a bump forming target, is held on each of the bonding stages 24 and 26. The bonding stages 24 and 26 are arrange | positioned on the case stage 28 of the bump forming apparatus 10, and are supported so that a movement to the Y direction of FIG. 1 is possible as mentioned above. Moreover, the heater for a heating is installed in the case stage 28 or the bonding stages 24 and 26 as needed of a bonding operation.

The bonding head 22 is used by the meaning which points here with the whole mechanism which performs bump formation work in a wide meaning here. That is, the bonding head 22 includes a spool 30 wound around the wire 8 for constituting the bump, a wire clamper 32 to control the movement by inserting or opening the wire 8, and a wire ( And a capillary 34 through which 8) is inserted and receives ultrasonic energy for wire bonding from an ultrasonic device (not shown). As the wire 8, for example, a gold wire having a diameter of several 10 μm can be used. In addition, a torch 36 for forming the end of the wire 8 into a ball shape is provided opposite to the end of the capillary 34, and the torch 36 is connected to a torch power source (not shown).

Bump formation by the bonding head 22 is performed as follows using a wire bonding technique. The wire 8 is inserted into the capillary 34 and the end of the wire 8 comes out from the end of the capillary 34. One polarity side of the torch power source, which is a high voltage power source (not shown), is connected to the torch 36, and the other polarity side is connected to the wire 8, specifically, the spool 30, or the like. The end of (8) is dropped by a suitable space distance, high pressure is applied therebetween, and the end of the wire 8 is melted by discharge or the like to form a ball-like shape. In this manner, the ends of the wires 8 are formed in a ball shape, and then pressed by the capillary 34 to the bonding pads of the chip 2, ultrasonic energy is supplied from an ultrasonic device (not shown), and the bonding pads are pressed. And wire 8 are bonded together. At this time, if necessary, a heating heater can be used as described above. When bonding between the bonding pads of the chip 2 and the wire 8 is made, the wire clamper 32 is closed and the capillary 34 is pulled up to break the wire 8.

In this way, since one gold ball shape is formed on the surface of the chip 2, it can be used as one bump. This can be repeated for each bonding pad of one chip 2 to obtain a chip having a plurality of bumps.

FIG. 3 shows an example of a sequence for efficiently forming bumps using two bonding stages 24 and 26. The two bonding stages 24 and 26 are movable in the Y direction shown in FIG. 1 under the control of the controller 80. Moreover, the bonding head 22 is movable in the XY plane shown in FIG. 1, and can also move to the Z direction perpendicular | vertical to an XY plane in a bonding operation. These figures show that the positional relationship of the bonding head 22, the two bonding stages 24, 26, and the chips 2, 3, 4 moves and changes with the passage of time of the bump formation in the bump forming section 20. It is shown using a plan view of the. Since the contents of the chip change as the bump formation progresses, the code is changed to a chip 2 in which bump formation has not yet started, a chip 3 in bump formation, and a chip 4 in which a plurality of bump formations are completed, The figure of the chip | tip 2 before bump formation is shown as the simple square figure, and the chip 4 after bump formation is shown as the rectangular figure which attached the oblique cross line.

Fig. 3 (a) shows a state in which the bonding head 22 is in a neutral state in the initial state, and the chip 2 is moved to the bonding stage 26 from the supply and accommodation tray 14, which is not shown, and is held. to be. In response, the bonding head 22 moves in the direction of the bonding stage 26.

In FIG. 3B, the bonding stage 26 holding the chip 2 moves in the Y direction, and bump formation is performed on the chip 3 by the bonding head 22. During this time, the chip 2 is moved from the supply and storage tray 14 (not shown) to the empty bonding stage 24 to be retained.

FIG. 3C shows a state in which bump formation is completed in the bonding stage 26 and the bonding stage 26 moves in the Y direction to return to its original position. The bonding head 22 moves in the direction of the bonding stage 24 via the neutral state at the position of the bonding stage 26. In addition, the chip 4 after bump formation is completed is transferred to the leveler portion 40 (not shown) in the bonding stage 26.

In FIG. 3D, the bonding stage 24 holding the chip 2 moves in the Y direction, and bump formation is performed on the chip 3 by the bonding head 22. In the meantime, the chip | tip 2 is moved and hold | maintained from the supply and accommodation tray 14 which abbreviate | omits illustration to the empty bonding stage 26. FIG. This process is the same except that only the bonding stage and the process of FIG.

3 (e) shows a state in which bump formation is completed in the bonding stage 24, and the bonding stage 24 moves in the Y direction to return to its original position. The bonding head 22 moves in the direction of the bonding stage 26 via the neutral state at the position of the bonding stage 24. In addition, the chip 4 in which bump formation is completed is transferred to the leveler part 40 (not shown) in the bonding stage 24. This process is the same except that only the bonding stage and the process of Figure 3 (c).

By repeating the above process, bump formation can be performed sequentially using the two bonding stages 24 and 26 efficiently.

The leveler section 40 is a work station having a function of uniformly matching the height of each bump of the chip 4 with respect to the chip 4 with bumps under the control of the leveler processing module 86 of the control unit 80. 4 shows the concept of uniformly adjusting the bump height. 4A shows the state of the chip 2 before bump formation, and no bump is formed on the bonding pad 5 of the chip 2 yet. FIG. 4B illustrates the chip 4 in which the bumps 7 are formed in the bump forming unit 20. As such, the bump 7 in the state after the bump formation has a different height depending on the bump 7 due to the remaining shape of the broken wire, etc., and the top thereof is not flat, so it is necessarily suitable for face down bonding, which is a subsequent process. It may not be. FIG. 4C is a view showing a state in which the bump height is made to be uniform H in the leveler portion 40, and the top portion thereof is also flattened to form the chip 6 with the bump 9 having a uniform height.

The leveler portion 40 includes a leveler head 42 and two leveler stages 44 that apply pressure to the top of each bump of the chip to uniformly adjust the height of the bumps. Although two leveler stages 44 are shown as one member in FIG. 1, two holding stages for holding bumped chips are provided in this one member. The two leveler stages 44 are working stages having a function of holding chips for height matching operations, which are movable in the Y direction shown in FIG. 1, and one of the two holding stages is used as the leveler head 42. It can be placed directly below, and further up and down in the Z direction is possible. The leveler head 42 can correct the height of the bump by giving a pressing force against the leveler stage 44 by raising one of the two holding stages directly below it. The leveler stage 44 has two holding stages, with bumped chips or bumps that are already uniform in height, when the leveling work is being performed in one holding stage, the next leveling in another holding stage. This is to wait for the chip.

5 is a diagram illustrating the components of the leveler portion 40. The leveler part 40 is a kind of pressing device fixed to the case stage 28 of the bump forming apparatus 10. The leveler part 40 is a mechanism for allowing the leveler stage 44 to move up and down in the Z direction with respect to the leveler head 42. Have The leveler head 42 has a rotational watch mechanism 46 called a swivel mechanism with a load cell 48 capable of measuring the pressing force therebetween, and is set in a fixed position with respect to the case stage 28 and in the Z direction. Do not move. The leveler part 40 has the vertical movement table 59 which can move to a Z direction, and the leveler stage 44 is provided on it. Up-and-down movement of the up-and-down movement stand 59 can be performed by the up-and-down movement mechanism 50 which used the plane movement drive of the wedge-shaped slope surface stand. The leveler stage 44 is a chip holding member having two holding stages 52, 54. The leveler stage 44 is movable in the Y direction shown in FIG. 1 in the surface of the guide table 58 with the slider mechanism 56 interposed.

FIG. 6 is a diagram showing an example of a sequence for efficiently performing bump height matching using two holding stages 52 and 54 of the leveler stage 44. As shown in FIG. These figures show how the positional relationship of the leveler head 42, the two holding stages 52 and 54 of the leveler stage 44, and the chips 4 and 6 move and change with the passage of time of the bump height adjustment. It shows using the top view and front view in 40. As shown to FIG. As the bump height adjustment progresses, the contents of the chip change, so here we change the sign to the bumped chip (4) where the height alignment has not yet begun, and the chip (6) where the height alignment has finished, and that the height adjustment has not yet started. As shown in Fig. 3, the bumped chip 4 is a square shape with oblique cross lines, and the bumped chip 6 whose height alignment is finished is shown as a black square shape.

FIG. 6A illustrates an arrangement in which the up-and-down moving table 59 is in a neutral state, that is, lowered in the initial state, in which the chip 4 has the second holding stage 54 in the bump forming unit 20 (not shown). Has been moved to and maintained. The first holding stage 52 is still empty in Fig. 6A.

FIG. 6B shows that the leveler stage 44 holding the chip 4 slides in the direction of the arrow shown in the drawing, that is, in the Y direction, and moves the second holding stage 54 of the leveler head 42. It moves to just below, and the up-and-down moving stand 59 raises there, and the leveler head 42 presses the bump of the chip 4, and the height of bump is adjusted.

6C shows a state where the height adjustment of the bump is completed by the leveler head 42, the vertical movement table 59 descends, and the leveler stage 44 moves in the Y direction to return to the original position. Indicates. Here, the bumped chip 4 is moved to the position of the first holding stage 52 which has been empty so far from the bump forming portion 20 (not shown). In addition, the chip 6 whose height alignment is completed is transferred to the supply and accommodation tray 14 not shown in the second holding stage 54. Thus, the second holding stage 54 is empty here.

6 (d) shows that the leveler stage 44 holding the chip 4 slides in the direction of the arrow shown in the drawing, that is, in the Y direction, and moves the first holding stage 52 directly to the leveler head 42. It moves to the bottom, and the up-and-down moving stand 59 raises there, and the leveler head 42 presses the bump of the chip 4, and the height of a bump is performed. This process is the same except that the process and the holding stage of Fig. 6B differ.

6E shows a state where the height adjustment of the bump is completed by the leveler head 42, the vertical movement table 59 descends, and the leveler stage 44 moves in the Y direction to return to its original position. Indicates. Here, the bumped chip 4 is moved and held in the bump formation part 20 (not shown) to the position of the second holding stage 54 which has been empty so far. In addition, the chip 6 whose height alignment is completed is transferred to the supply and accommodation tray 14 not shown in the first holding stage 52. This process is the same in content except that only the process of FIG.6 (c) and a maintenance stage differ.

By repeating the above process, it is possible to efficiently use the two holding stages 52 and 54 of the leveler stage 44 to sequentially adjust the height of the bumps.

The chip collet conveying unit 60 holds the chips under the control of the conveyance processing module 88 of the control unit 80 to supply and receive the tray 14, the bump forming unit 20, the leveler unit 40, and supply and store the chips. It has a function of moving between the trays 14. The chip collet conveying unit 60 includes a chip collet 62 for picking (grabbing) and placing a chip (positioning arrangement) and a Y moving mechanism 64 for supporting the chip collet 62 to be movable in the Y direction. And an X moving mechanism 66 that supports the Y moving mechanism 64 to be movable in the X direction. As the X moving mechanism 64 and the Y moving mechanism 66, for example, a moving mechanism using a linear motor can be used.

The chip collet 62 is a chip holding member having a function of holding or releasing a chip. Specifically, a mechanism for releasing the catch by holding the chip by vacuum suction and blocking the vacuum can be used. 7 is a cross sectional view of the chip collet 62, as shown herein, the chip collet 62 has two collet heads 68, 70. As shown in FIG. The collet head 68 is a bumpless chip collet head capable of holding a chip 2 without bumps, that is, a bumpless chip 2 and releasing the grip. The collet head 70 is a bumped chip collet head capable of holding the chip 4 after bump formation, that is, the bumped chip 4, and releasing the grip. The collet heads 68 and 70 can be assembled so as to be interchangeable by inserting them into the chip collet 62 or the like.

The bumpless chip collet head 68 has a jaw portion for supporting the outer periphery of the chip 2 and holds the chip 2 by vacuum suction by vacuuming a space surrounded by the jaw portion and the chip 2. In order to release a catch, it can carry out by interrupting a vacuum or introducing a gas for release. In addition, the bumped chip collet head 70 can use what provided the vacuum suction hole simply in the center of a flat plate. The holding of the chip 4 can be performed by vacuuming a space surrounded by the flat plate portion of the collet head 70 and a plurality of bumps, and the catching can be performed by blocking the vacuum or introducing a gas for release.

Next, the whole operation | movement in the bump forming apparatus 10 of the said structure is demonstrated. FIG. 8 is a diagram illustrating a part of a sequence of continuous operation in the bump forming apparatus 10. Fig. 8 shows six graphs and one state change diagram showing the operating states of the respective components by holding the horizontal axis at a common time. The six graphs are the operation graph of the bonding stage BSL (the bonding stage 24 on the left side in FIG. 1), the operation graph of the bonding stage BSR (the bonding stage 26 on the right side in FIG. 1), and the leveler stage LV1 (in order from the top). 6, the operation graph of the holding stage 52 on the left side, the operation graph of the leveler stage LV2 (the holding stage 54 on the right side on FIG. 6), the graph showing the moving position of the chip collet 62, and the chip collet ( Fig. 62 is a graph showing the XY shift. One state diagram is a diagram showing a state change of the pick (grab) and place (positioning arrangement) of the chip collet 62.

The operation graphs of the bonding stage BSL and the bonding stage BSR are the two top graphs in FIG. 8. In this graph, the L state represents a state in which bump formation is not performed, and the H state represents a state in which bump formation is performed. The transition state between H and L indicates the rise and fall of the bump forming operation. Therefore, in these graphs, the bump forming operation period is a period other than the L state while rising from the L state to the H state and returning to the L state again. In the example of FIG. 8, the bump forming operation period is about 3.O sec, and the bump forming operation cycle time per one bonding stage is about 8.2 sec. Thus, by using two bonding stages, the overall bump forming work cycle time of the bump forming apparatus 10 is about half that, about 4.1 sec.

The operation graphs of the leveler stages LV1 and LV2 are two graphs, 3rd and 4th, from above in FIG. 8. In this graph, the L state represents a state in which bump height matching is not performed, and the H state represents a state in which bump height matching is performed. The transition state between H and L indicates the rise and fall of the height matching operation. Therefore, in these graphs, the non-L period during the rising from the L state to the H state and returning to the L state is the bump height matching operation period. In the example of FIG. 8, the bump height fitting operation period is about 2.5 sec. The bump height matching work cycle time per one holding stage is about 8.2 sec, which is the same as the bump forming work cycle time. By using two holding stages, the bump forming apparatus 10 overall bump height matching work cycle time is about half that. 4.1 sec.

The graph showing the moving position of the chip collet 62 is the fifth most complicated graph from the top in FIG. In this graph, the vertical axis indicates the position of the chip collet 62, the position of the TRAY (feeding and receiving tray 14) from below the vertical axis, the position of the BSR (bonding stage 26), and the BSL (bonding). The position of the stage 24), the position of the LV2 (holding stage 54), and the position of the LV1 (holding stage 52) are shown.

In FIG. 8, the graph immediately below the graph showing the moving position of the chip collet 62 is a graph showing the XY movement of the chip collet 62. Here, it is shown that the XY movement is made in the H state. That is, when this graph is matched with the movement position graph of the chip collet 62 immediately above, the chip collet 62 corresponds to TRAY, BSL, BSR, LV1, and LV2 corresponding to the H state indicating XY movement. You can see that we are changing the location.

The state diagram shown at the bottom in FIG. 8 shows that the chip collet 62 is performing a so-called pickup where the chip is attracted and held, or the chip collet 62 moves the chip to a predetermined place and then positions it there. It shows that the catch is released and placed. When the state variation and the XY shift graph of the chip collet 62 are associated with each other, it can be seen that the pick and place of the chip collet 62 is performed when the XY shift is not performed. Accordingly, it can be seen that the chip collet 62 changes its position in accordance with the XY movement, and always performs either a pick (grabbing) or a place (positioning arrangement) in a predetermined order at the changed position.

FIG. 9 is a diagram for explaining the position of the chip collet 62 and the time variation with respect to picking and placing (positioning arrangement). Here, the operation of the chip collet 62 between about 10 sec and 15 sec at the time shown in FIG. 8 will be described using the plan view of the bump forming apparatus 10.

9A shows a state in which the chip collet 62 moves in the supply and storage tray 14 immediately after the time 10 sec to hold the chip 2 before the operation. At this time, the bonding head 22 is going to finish bump formation in the bonding stage 24 (BSL). In addition, the leveler head 42 has the holding stage 54 (LV2) just below it, and bump height matching is performed.

FIG. 9B is a view showing a state in which the chip collet 62 moves the chip 2 from the supply and accommodation tray 14 to the bonding stage 26 (BSR), and the chip collet movement position graph of FIG. 8. Corresponds to the state indicated by (b). Here, the chip collet 62 is empty.

FIG. 9C shows a state in which the bonding stage 24 (BSL) in which bump formation is completed is moved and returned to its original position. The empty chip collet 62 then moves from the bonding stage 26 (BSR) to the bonding stage 24 (BSL), where it grabs the bumped chip 4 where bump formation is complete. This state corresponds to the state shown by (c) in the chip collet movement position graph of FIG.

9 (d) shows a state in which the holding stage 54 (LV2) in which bump height matching is finished has moved and returned to its original position. Here, the holding stage 52 (LV1) is empty. The chip collet 62 then transfers the bumped chip 4 from the bonding stage 24 (BSL) to this holding stage 52 (LV1). Here, the chip collet 62 is empty. At this time, the bonding stage 26 (BSR) is moved to start the bump formation by the bonding head 22. This state corresponds to the state indicated by (d) in the chip collet movement position graph of FIG.

In Fig. 9E, the empty chip collet 62 moves from the holding stage 52 (LV1) to the holding stage 54 (LV2), where it holds the bumped chip 6 whose height is uniform. This state corresponds to the state shown by (e) in the chip collet movement position graph of FIG.

FIG. 9 (f) shows a state in which the chip collet 62 moves the bumped chip 6 with a uniform height from the holding stage 54 (LV2) to the supply and accommodation tray 14. This state corresponds to the state indicated by (f) in the chip collet movement position graph of FIG.

Supply and storage tray 14-bonding stage 26-bonding stage 24-holding stage 52-holding stage 54-supplying and receiving tray 14 in the operation of (f) in FIG. A sequence of operations ends). This cycle time is about 4.1 sec in the example of FIG. 8.

Fig. 9 (g) is a view corresponding to Fig. 9 (a), in which the chip collet 62 is moved in the supply and receiving tray 14 to hold the chip 2 before the operation in a state before and after 15 sec. to be. 9 (a), the bonding head 22 is about to end bump formation at the bonding stage 26 (BSR), and the leveler head 42 has the holding stage 52 (LV1) immediately below it. Is arranged so that bump height matching is performed. That is, the bonding stage and the holding stage are replaced on the other side of the case of Fig. 9A.

FIG. 9 (h) is a view corresponding to FIG. 9 (b), showing the state in which the chip collet 62 moves the chip 2 from the supply and receiving tray 14 to the bonding stage 24 (BSL). It is a figure and the bonding stage is replaced with the other side in FIG.9 (b). Thus, the bump forming operation is continued by replacing the bonding stage and the holding stage with the other side. Then, counting starts from FIG. 9 (a), and returns to the state of FIG. 9 (a) after about 8.2 sec. During this time, the bump forming operation and the height matching operation are performed two by two, so that the cycle time of the entire bump forming apparatus 10 is about 4.1 sec.

In addition, the chip collet 62 includes the bumpless chip collet head 68 and the bumped chip collet head 70 as described above, so that the chip between the supply and accommodation tray 14-the bonding stage 26 ( It is preferable to replace so that the conveyance of 2) may use the bumpless chip collet head 68, and other conveyances may use the bumped chip collet head 70.

According to the above configuration, the total cycle time of bump formation and height alignment should be about 4.1 sec, compared to about 3 sec of bump formation operation time and about 2.5 sec of bump height adjustment operation time. Significantly improved productivity compared to serial working time. In addition, there is no need to increase the number of the holding portions of the chip collet 62 in particular.

The sequence has several features. First, the chip collet carrying the chip efficiently repeats the pick and place (positioning arrangement) of chips, etc. in the order of supply (and storage) tray-bonding stage-leveler stage- (feed and) storage tray. do. That is, catching chips in the supply tray-moving chips to the bonding stage where bump formation is to be performed-catching chips with bumps from the bump forming bonding stage-moving the bumped chips to the leveler stage which will perform the height adjustment-bumping at the leveler stage where the height alignment is finished Holding chips-Move chips and other chips in order of transferring bumped chips with uniform height to the storage tray.

Secondly, the chip after the bump formation is completed is immediately transferred to the leveler stage, the bumped chip having a uniform height is directly transferred to the storage tray, and the chip is transferred directly to the bonding stage where bump formation is to be made from now on. Therefore, there is no waste of waiting for each job or the like.

Third, the first pick and place, the bonding stage- in the feed tray-bonding stage, in order to hold and move while maintaining the basic flow of the supply tray-bonding stage-leveler stage-storage tray and not to interrupt the pick and place. Configure a second pick and place in the leveler stage and a third pick and place in the leveler stage-storing tray. Then, the bonding stage of the first pick and place is different from the bonding stage of the second pick and place, so that the former will bond from now on, and the latter will end. Similarly, the leveler stage of the second pick-and-place and the leveler stage of the third pick-and-place are different, so that the former adjusts the height from now on and the latter adjusts the height.

Fourth, the cycle time for uniformly matching the height of the bump per one leveler stage and the bump time per one bumper stage is shorter than the transfer cycle time from the supply tray to the storage tray. In the above example, the transfer cycle time from the supply tray to the storage tray is about 4.1 sec, which is shorter than about 3.O sec of the bump forming operation time and about 2.5 sec of the bump height matching operation time. Therefore, the production cycle time of bumped chips with uniform height is determined by simply the transfer cycle time without being affected by the cycle time required for bump formation or the cycle time required for height matching. That is, productivity can be improved by shortening a conveyance cycle time, regardless of the time of bump formation and the time of height matching in the range.

The chip collet which has two or more bump stages and two or more leveler parts by the above structure, and picks up and moves chips between them is picked and placed such as chips in the order of supply tray-bonding stage-leveler stage-storing tray. (Positioning arrangement) is repeated efficiently. That is, grab the chip from the supply tray-move the chip to the bonding stage where bump formation will occur-grab the bumped chip from the bump forming bonding stage-move the bumped chip to the leveler stage that will do the height adjustment-finish the height alignment Catch bumped chips in the leveler stage-pick up the chips and move them in the order of moving the bumped chips with uniform height to the storage tray.

That is, the chip after the bump formation is completed is immediately transferred to the leveler stage, the chip having a uniform uniform height is immediately transferred to the storage tray, and the chip is immediately transferred to the bonding stage where bump formation is to be performed from now on. Therefore, there is no waste of turn waiting for each job. Here, the shape of the holding part may be changed to another one for the protection of the bump shape before and after the bump formation, as well as the holding part for holding and moving the chip. Therefore, productivity can be improved, without increasing the kind of holding | maintenance part of the holding tool which carries a chip | tip and moves.

In addition, since the cycle time required for bump formation per one bump stage and the cycle time during which the height of the bumps per one leveler stage are uniformly controlled are shorter than the transfer cycle time from the supply tray to the storage tray, the bump height is uniform. The cycle time of the production of the chip is determined by only the transfer cycle time without being affected by the cycle time required for bump formation or the cycle time required for height matching. Therefore, productivity can be improved by shortening a conveyance cycle time without depending on the time of bump formation or the time of height matching in the range.

In addition, since the chip chip collet for bumpless chips and the chip collet for bumped chips are selected, deformation of the bump shape and the like can be prevented.

In addition, since the plurality of leveler stages have one slide type leveler arranged in the moving direction, one pressurizing device for height matching is required, so that the productivity can be improved with a simple configuration.

As mentioned above, according to the bump forming apparatus which concerns on this invention, productivity can be improved, without increasing the kind of holding part of the holding tool which carries a chip | tip and moves.

Claims (4)

In a bump forming apparatus for forming a plurality of bumps having a uniform height on the chip, Supply tray for supplying chips, A bump forming unit for forming a plurality of bumps on a chip, the bump forming unit having two or more bump stages, and when bumps are formed on a chip in one bump stage, another bump stage is next to a chip or a chip in which bumps are to be formed. Atmospheric bump formation, A leveler section that uniformly matches the heights of a plurality of bumps formed, wherein the leveler section has two or more leveler stages, and when one of the leveler stages uniformly adjusts the height of the bumps, another leveler stage is next bumped chip or already The leveler part which waits the chip with the bump which matched the height uniformly, A storage tray for storing chips with a uniform height of bumps, A chip collet conveying unit for exchanging and conveying chips using a chip collet between a supply tray, a bump forming unit, a leveler unit and a storage tray, and A control unit for controlling a cycle time of bump formation,   The control unit,   Means for causing the chip collet to hold the first chip in the feed tray,   Means for moving the chip collet holding the first chip and positioning the bump collet in the bump stage on the side where bump formation is to be made;   Means for moving the empty chip collet to the bump stage on the side where bump formation has already been completed, and catching the second chip which is already formed and waiting for bumps,   A means for moving the chip collet holding the second chip and positioning the chip collet on the leveler stage on the side where the leveler portion is to be height-adjusted from now on,   Means for moving the empty chip collet to the leveler stage on the side where bump height matching has already been completed, whereby the height is uniform and held to hold the third chip waiting; and   And a means for moving the chip collet catching the third chip, positioning and storing the chip collet in the storage tray. The method according to claim 1, wherein the cycle time for uniformly matching the height of the bumps per one bumper stage and the height of the bumps per one leveler stage is shorter than the transfer cycle time starting from the supply tray to the storage tray. Bump forming apparatus, characterized in that. The method of claim 1, Chip collet conveying unit, A chip collet for a bumpless chip having a grip shape for holding a bumpless chip in which bumps have not yet been formed, and A bump chip chip collet having a grip shape for holding a bumped chip in which bumps are already formed, And the control unit selects a chip collet to be used by the chip collet conveying unit according to the bumpless chip and the bumped chip. The method of claim 1, The leveler section is a slide leveler stage in which a plurality of leveler stages are arranged in a moving direction, and has a leveler stage for moving any one leveler stage in a work area of a pressing mechanism to uniformly press a bump at a predetermined height. Bump forming device.

Images