JPH08335609A - Chip bonder - Google Patents

Abstract

PURPOSE: To reduce a bonding cycle by promptly supplying semiconductor chips to a bonding tool of a bonding head. CONSTITUTION: This bonder comprises: a bonding head 4 mounted so as to be always positioned in a bonding position B; and a chip supplier 25 for transferring semiconductor chips 1 supplied to a bonding tool 3 of this head 4. When a chip slider 2 of the chip supplier 25 is moved from a temporary stop position C to a chip transfer position E under a lower end of the bonding tool 3, the bonding tool 3 is moved from an upward stand-by position to downwardly and vacuum-chucked to hold the semiconductor chips 1 on the chip slider 2, and further the empty chip slider 2 moves to a chip supply position D and receives the next semiconductor chip 1 therein to move to the temporary stop position C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip bonding apparatus for bonding semiconductor chips to various circuit boards such as liquid crystal boards.

[0002]

2. Description of the Related Art Conventionally, a chip bonding apparatus for bonding a semiconductor chip to various circuit boards such as liquid crystal boards has been known.

For example, in Japanese Unexamined Patent Publication No. 4-322492 or Japanese Unexamined Patent Publication No. 3-46244, a bonding head equipped with a bonding tool capable of vacuum suction holding a semiconductor chip so as to move up and down is supplied to the left and right chips. It is suspended on the upper rail so that it can reciprocate between the position and the bonding position, and the semiconductor chip is vacuum-held by the bonding tool that is moved to the chip supply position by the movement control of the head, and then it is moved to the bonding position. There is disclosed a chip bonding apparatus that moves and then bonds the circuit board at this position. As described above, the conventional chip bonding apparatus is a so-called movable type in which the bonding head equipped with the bonding tool reciprocates between the left and right chip supply positions and the bonding positions.

[0004]

However, in this movable apparatus, since the bonding head is a large heavy object due to its structure, when it is controlled to move at high speed, it is vibrated by a shock when it is stopped. Occurred, and the time until it stood still became relatively long, and this hindered rapid chip bonding, which required bonding accuracy in the micron range, that is, short-cycle bonding. . In order to speed up chip bonding, it has been considered to configure a bonding head so that a plurality of semiconductor chips can be simultaneously vacuum-sucked and held, but from the viewpoint of preventing the weight of the bonding head from increasing. , It was difficult.

In view of these drawbacks, the present invention has made earnest studies to solve them, and as a result, while mounting the bonding head so that it is always positioned at the bonding position, the semiconductor chip is mounted on the head. It has been found that, by mounting a supply device for supplying, the semiconductor chip can be rapidly supplied to the bonding tool of the bonding head, and the bonding cycle can be shortened.

[0006]

That is, in the chip bonding apparatus according to the present invention, a bonding head having a bonding tool capable of holding a semiconductor chip by vacuum suction so as to move up and down is always positioned at the bonding position. In addition to the above-mentioned mounting, a chip supply device for transferring the semiconductor chip is mounted to the chip passing position below the lower end of the bonding tool which has been moved to the standby position.

It is preferable that the chip supply device is equipped with a chip slider mounted so as to be guided and moved by a rail while keeping the chip holding portion for holding the semiconductor chip horizontal.

Further, it is preferable that the chip holding portion of the chip slider is configured to hold a plurality of semiconductor chips.

Further, it is preferable that the chip holding portion of the chip slider is constructed so as to hold the semiconductor chip by vacuum suction.

Further, it is preferable that the chip slider is mounted so as to reciprocate between a chip supply position where a semiconductor chip is supplied to the chip holding portion and a lower end position of the bonding tool.

When the chip slider is mounted so as to be able to reciprocate in such a manner, it moves from the chip supply position to a temporary stop position near the bonding head during bonding, and then the bonding tool waits. It is preferably mounted so that it can be moved to the tip passing position when moved to the position.

[0012]

In FIG. 1, the chip slider 2 holding the semiconductor chip 1 of the chip supply device 25 is moved to the chip transfer position E below the lower end of the bonding tool 3 which is moved to the standby position above the bonding head 4. When it is moved, the bonding tool 3 is moved downward and abutted lightly on the semiconductor chip 1 on the chip slider 2 to hold the chip 1 by vacuum suction, and then to the original upper standby position (origin). Position).

On the other hand, the empty chip slider 2 is moved from the chip transfer position E to the chip supply position D. Then, the bonding tool 3 is moved downward again to be brought close to the circuit board on the lower boding stage (not shown), and then the piston rod 9 of the air cylinder 8 is projected to lower the pressure transmission shaft 10. Is pushed to. Therefore, the bonding tool 3 is pushed downward by the pressure transmission shaft 10 and a predetermined bonding pressure is applied, so that the semiconductor chip 1 can be thermocompression bonded, that is, bonded to a circuit board (not shown).

During the bonding, the chip slider 2 holding the semiconductor chip 1 is moved from the chip supply position D to a temporary stop position C close to the bonding head 4, and after the bonding, the bonding tool 3 is finished. Is returned to the upper standby position (origin position), it is moved to the chip passing position E. Therefore, the semiconductor chips 1 can be quickly supplied to the bonding tool 3 at the standby position, and bonding can be performed one after another in a short cycle.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 2, which is a front view showing the overall structure of a chip bonding apparatus, a chip loader 30 holds a semiconductor chip 1 in a chip tray 31 by vacuum suction and holds it by a chip slider 2 at a chip supply position D. Supply to. At that time, the chip tray 3 is moved by moving in the X direction (horizontal direction) and in the Y direction (front-back direction) orthogonal to this direction and moving the vacuum suction pad 32 in the Z direction (vertical direction).
The semiconductor chip 1 in 1 is suction-held by vacuum, and then the suction-holding position is positioned at F.

That is, as shown in FIG. 3, this is in the state where the semiconductor chip 1 is positioned between the pair of L-shaped chip pressing plates 34 mounted on the upper surface of the outer shape positioning table 33. , The chip loader 30 is slightly moved in the XY directions so that the semiconductor chip 1 is brought into contact with both the chip pressing plates 34, whereby the central portion of the semiconductor chip 1 is vacuum-sucked and held. And then
The semiconductor chip 1 is supplied to the chip supply device 25, and this supply is performed to the chip slider 2 which has been moved to the chip supply position D.

As shown in FIG. 4 and FIG. 5, which is a side view of the chip supply device 25,
The slider bracket 35 mounted on a device frame (not shown), the rail 7 mounted horizontally on the bracket 35, the screw shaft 36 rotatably mounted on the slider bracket 35, and the screw shaft 36. A drive device 39 for forward / reverse rotation driving via a servo motor 37 and a winding transmission means (timing belt and timing pulley) 38 is slidably engaged with the rail 7 and screwed to a screw shaft 36. Chip slider 2
It consists of and.

Therefore, the chip slider 2 can be reciprocated between the chip supplying position D and the chip passing position E by driving and rotating the screw shaft 36 in a predetermined direction by the driving device 39. The rider 2 holds the chip holder 2a horizontally while keeping the rail 7
Will be guided and moved. An air intake hole 2b is opened on the upper surface of the chip holding portion 2a, and the air intake hole 2b is formed.
An intake port 2c communicating with b is opened on the side surface, and one end of a pressure-resistant hose connected to a vacuum pump (not shown) is connected to the intake port 2c.

In addition, as shown in FIG. 1, the chip supply device 25 having the above-described structure has the chip below the lower end of the bonding tool 3 in the standby position moved to the upper standby position (origin position). It is mounted so that the tip slider 2 can be positioned at the transfer position E. Therefore,
When the chip loader 30 supplies the semiconductor chip 1 onto the chip holding portion 2a of the chip slider 2 at the chip supply position D, the semiconductor chip 1 can be vacuum-sucked and held and transferred to the chip passing position E. At that time, the bonding head 4 on which the bonding tool 3 is mounted
The chip slider 2 is stopped at the temporary stop position C approached to, and is moved to the chip passing position E after a lapse of a predetermined time.

On the other hand, the bonding head 4 is mounted so that it is always located at the bonding position B, that is, it is mounted at the bonding position B so that it cannot be moved to another place. More specifically, in FIG. 1, the Z table 6 and the vertical guide 12 for the bracket are fixed to a device frame (not shown), and the reaction force receiving column 13 is also
Its lower end is fixed to a device frame (not shown). The Z table 6 includes a screw shaft feed mechanism (not shown) that rotates the screw shaft by the servo motor 14 to feed the pitch, and the head bracket 5 is associated with this mechanism. Therefore, when the head bracket 5 is moved through such a mechanism, the bonding tool 3 and the pressure transmission shaft 10 mounted on the head bracket 5 are moved together.

The bonding tool 3 is capable of holding the semiconductor chip 1 by vacuum suction and having a built-in heater so that it can be quickly heated to a predetermined temperature by a pulse heater control device (not shown). The elastic body (coil bar) 15 is suspended by the head bracket 5 via the body (coil bar) 15, that is, the pin 16 mounted on the head bracket 5 and the pin 17 mounted on the bonding tool 3. . An elastic body (coil bar) 15 is also locked on the A side on the left side. Therefore, the bonding tool 3 slides in the vertical direction guided by the pair of tool vertical guides 18 mounted on the head bracket 5 (also mounted on the side opposite to the illustrated side). be able to.

The pressure transmission shaft 10 is supported by a bearing 19 mounted on the head bracket 3. The lower end of the pressure transmission shaft 10 is brought into contact with the upper end of the bonding tool 3 to prevent it from coming off, and the upper end thereof. The head bracket 3 is mounted so that it can be vertically slid through the head bracket 5 so as to project above the upper surface of the head bracket 3 for a certain length.

Therefore, by pressing the pressure transmission shaft 10 downward, the bonding tool 3 can be guided downward by the left and right tool vertical guides 18 and the pressing can be released. It can be returned to the original origin position above. This state is shown in FIG.

The cylinder bracket 11 is slidably engaged with the bracket vertical guide 12 and is suspended from the reaction force receiving column 13 via the elastic body (coil bar) 20, that is, the cylinder bracket. Pin 21 mounted on 11 and pin 22 mounted on the reaction force receiving column 13
An elastic body (coil bar) 20 is locked at the position. A load cell 23 is mounted on the upper surface side of the cylinder bracket 11, and an air cylinder 8 is mounted on the lower surface side thereof so that the piston rod 9 can be projected downward. The piston rod 9, the pressure transmitting shaft 10, and the bonding tool 3 are separated from the force receiving column 13 at a predetermined interval, and are vertically concentric with each other. Since the shaft 10 is usually separated from each other at a constant interval, the chip slider 2 of the chip supply device 25 vacuum-sucks the semiconductor chip 1 transferred to the chip passing position E with the bonding tool 3. The tool 3 is held, and then the tool 3 is once moved to an upper standby position, and then moved downward to move to the boding stage 40 (see FIG. 2). After approaching the circuit board 41 supported by the air cylinder 8, the piston rod 9 of the air cylinder 8 is projected and the pressure transmission shaft 10 is pressed downward, whereby the bonding tool 3 is pressed downward and a predetermined bonding pressure Therefore, the semiconductor chip 1 can be thermocompression bonded, that is, bonded to the circuit board 41.

As described above, since the bonding head 4 is mounted so that it is always located at the bonding position B, the chip supply device 25 for supplying the semiconductor chip 1 to the head 4 is mounted, so that the bonding is performed. The semiconductor chips 1 corresponding to three bonding tools of the head 4 can be rapidly supplied, and the bonding cycle can be shortened. Further, since the chip supply device 25 is configured to have the chip slider 2 which is guided and moved by the rail 7, the chip supply device 25 can be made compact and lightweight.

When the bonding tool 3 holds the semiconductor chip 1 transferred to the chip transfer position E by vacuum suction and moves it to the upper standby position, the empty chip slider 2 moves the chip transfer position E to the chip transfer position E. To the chip supply position D, and while the bonding tool 3 holding the semiconductor chip 1 by vacuum suction is moved downward to perform bonding, the semiconductor chip 1 to be subsequently bonded is temporarily stopped. Transfer to C.

Subsequently, the bonding tool 3 which has completed the bonding is moved to the standby position above and at the same time,
The circuit board 41 positioned at the bonding position B
2 is transferred to the retreat position G on the left side of the bonding position B as shown in FIG. 2, at which time, the boarding stage 40 supporting the circuit board 41 is controlled to move in a predetermined manner. The boarding stage 40 is X
It is composed of a Yθ table.

After that, when the chip slider 2 at the temporary stop position C is moved to the chip transfer position E, the bonding tool 3 is moved downward from the upper standby position, and the semiconductor chip 1 on the chip slider 2 is moved. Hold by vacuum suction. Hereinafter, by repeating such a process, bonding can be performed one after another. Prior to that, the boarding stage 40 is moved from the left retracted position G to the bonding position B and the circuit board 41 is transferred to the bonding position B. In this state, the semiconductor chip 1 vacuum-sucked and held by the bonding tool 3
And the circuit board 41 supported by the boarding stage 40 is precisely positioned.

That is, the CCD camera 42 detects (imaging) the alignment mark of the semiconductor chip 1 held by the bonding tool 3 moved to the standby position by vacuum suction.
Then, as shown in FIG. 2, the CCD camera 42 is moved from the imaging position to the retracted position H on the right side of the bonding position B, and then the boding stage 40 is moved from the retracted position G on the left side to the bonding position. After moving the circuit board 41 to the bonding position B by moving it to B, the alignment mark on the board 1 is moved to the CCD camera 4
The position deviation amount of both alignment marks is calculated in the image processing system, and the fine movement control of the boding stage 40 is performed based on the result.

The CCD camera 42 is moved to the retracted position H via the movement control of the XYZ table on which it is mounted.
And an alignment detection position (imaging position) and a predetermined level suitable for detection. Further, the bonding tool 3 communicates with the intake passage by sucking air through a pressure-resistant hose having one end connected to an intake passage (not shown) opened at a lower end side thereof. The semiconductor chip 1 can be vacuum-sucked and held by sucking air from the suction hole opened in the lower end surface (chip suction-holding surface) of the tool. The other end of the pressure-resistant hose is connected to a vacuum pump (not shown). Has been done.

When the chip slider 2 holding the semiconductor chip 1 by vacuum suction is moved to the chip passing position E below the bonding tool 3, the Z table 6 is driven to move the bonding tool 3 together with the head bracket 5. It is moved downward, and the lower end surface of the tool is lightly contacted with the semiconductor chip 1 on the slider 2. Then, the vacuum pump is driven, whereby the semiconductor chip 1 can be held by vacuum suction. At that time, the intake air in the tip slider 2 is stopped.

Subsequently, the bonding tool 3 capable of holding the semiconductor chip 1 by vacuum suction is moved together with the head bracket 5 to the original upper position, that is, the standby position by driving the Z table 6. On the other hand, the empty chip slider 2 moves from the chip transfer position E to the chip supply position D.
Moved to. The chip slider 2 is always moved while keeping the chip holding portion 2a horizontal.

Then, the semiconductor chip 1 is received at the chip supply position D and is moved from here to a temporary stop position C which is close to the bonding tool 3. In addition, the temporary stop position C
Is preferably located as close to the bonding head 4 as possible, and the movement to the position C is performed while the bonding tool 3 is moved downward to perform bonding, and the bonding tool 3 finishes bonding. When it is moved to the upper origin position, that is, moved to the standby position, it is moved from the temporary stop position C to the chip passing position E.

The bonding tool 3 moved to the standby position above while holding the semiconductor chip 1 by vacuum suction is
Then, by driving the Z table 6, the circuit board on the lower boding stage (not shown) is brought close to the Z board 6, and the bonding pressure is applied by the air cylinder 8. Although the upper end of the pressure transmission shaft 10 and the lower end of the piston rod 9 of the air cylinder 8 are separated at a constant interval when the bonding tool 3 is moved to the upper standby position (origin position), The protrusion of the piston rod 9 of the air cylinder 8 brings them into contact with each other, and the downward movement of the pressure transmission shaft 10 gives a predetermined bonding pressure to the bonding tool 3.

Further, when a predetermined bonding pressure is applied to the bonding tool 3 in this way, the reaction force thereof passes through the bonding tool 3, the pressure transmission shaft 10 and the piston rod 9 of the air cylinder 8 and the cylinder bracket 11 Act on. Then, the bracket 11 is guided by the vertical bracket guide 12 and slid upward, and the load cell 2 on the upper surface side of the cylinder bracket 11 is guided.
3 is brought into contact with the reaction force receiving column 23.

Therefore, the engaging portion between the cylinder bracket 11 and the vertical guide 12 for the bracket, and the Z table 6
It is possible to prevent an excessive moment from acting on the cooperation portion between the head bracket 5 and the head bracket 5, and thus the parallelism of the chip suction holding surface (the lower end surface of the bonding tool) of the bonding tool 3 with respect to the bonding surface of the circuit board. It can be kept constant, and high-accuracy bonding, which is difficult in the conventional bonding head, can be reliably performed. That is, 10 μ or less,
In particular, thermocompression bonding can be performed with an accuracy of 5 μm or less.

In addition, since the chip slider 2 is mounted so as to reciprocate between the chip passing position E and the chip supplying position D, the moving distance of the chip slider 2 can be shortened and the bonding head 4 can be used. The chip slider 2 can be quickly moved to the chip passing position, and the chip slider 2 and Since the bonding tool 4 is of a vacuum suction type, various semiconductor chips 1 having different sizes and shapes can be bonded one after another.

When the cylinder bracket 11 tries to move excessively upward during bonding, the load cell 23 can detect a reaction force and keep the bonding pressure constant. Since it is possible to control the bonding force and the pressing force, it is possible to stabilize the bonding conditions, and it is possible to perform not only one-step pressing but also multi-step pressing (step pressing), and thus stable bonding. Conditions can be selected, and since the air cylinder 8 is also moved up and down, the load cell 23 can also measure the applied pressure.

After the bonding is completed, the piston rod 9 of the air cylinder 8 is retracted and moved to the upper origin position, and the suction by the vacuum pump is stopped and the Z table 6 is driven to bond the tool. 3 is moved to the upper standby position (origin position).
In this way, you can bond one after another. When the pressure transmission shaft 10 is short, the same effect can be obtained by connecting the shaft 10 to the piston rod 9.

Although one embodiment according to the present invention has been described above, in the present invention, the circuit board to be bonded is not limited to a transparent substrate such as a liquid crystal substrate and may be another opaque circuit substrate. Good. Further, it is preferable to mount the load cell, but it can be omitted, and in the case of mounting the load cell, in addition to a mode in which the load cell is mounted so as to come into contact with the reaction force receiving column when the bonding pressure is applied, the bonding pressure is applied. It can be mounted in an appropriate mode as needed so that it is lightly abutted even when it is not.

Further, the tip supply device 25 may be constructed as a type in which the tip slider 2 is circulated in one direction,
In order to shorten the moving distance, a reciprocating type is preferable. Further, the chip slider 2 is configured to hold the semiconductor chip 1 by vacuum suction, and
The chip holding portion 2a may have a type in which a concave or convex frame body having a predetermined shape for holding the semiconductor chip 1 is formed. However, in this case, it is not possible to deal with various semiconductor chips 1 having different sizes and shapes, and therefore, it is preferable to configure the type in which vacuum suction and holding are performed, and simultaneous supply of a plurality of semiconductor chips 1 to the bonding tool 3 is possible. In order to achieve this, the chip holding portion 2a is preferably configured to hold a plurality of semiconductor chips 1.

Also regarding the bonding head 4,
As long as the semiconductor chip 1 can be vacuum-sucked, another type, for example, a type incorporating a fine movement stage for precise alignment shown in FIG. 6 may be used. In this case, an XY table 26a constituting an upper part of an XYθ table 26, which is a fine movement stage for precise positioning, is fixed to the head bracket 5, and
The θ table 2 which constitutes the lower part of the XYθ table 26
A tool bracket 27 is fixed to 6b, and a bonding tool 28 is attached to this bracket 27.

The bonding tool 28, like the bonding head 4, can hold the semiconductor chip 1 by vacuum suction and has a built-in heater so that it can be heated to a predetermined temperature by a pulse heater controller (not shown). However, the guide portion 28a formed in this
Is slidably inserted into a hole-shaped vertical guide 27a formed in the tool bracket 27. Therefore, when the head bracket 5 is moved downward by driving the Z table 6, the bonding tool 28 also moves in the same direction following the tool bracket 27 that is moved downward integrally with the bracket 5. And, on the contrary,
When the head bracket 5 is moved upward, the bonding tool 28 is also moved in the same direction.

Further, a plurality of such bonding tools 3 or 28 may be mounted so that a plurality of semiconductor chips 1 can be bonded simultaneously or alternately, and the bonding tools 3 or 28 and the chip slider 2 can be bonded together. The bonding tool 3 or 28 that holds the semiconductor chips 1 by vacuum suction one by one
And a chip slider 2 that holds a plurality of semiconductor chips 1, or a combination of a bonding tool 3 or 28 that holds a plurality of semiconductor chips 1 by vacuum suction and a chip slider 2 that holds a plurality of semiconductor chips 1. Etc. may be provided in various modes.

[0045]

As described above, according to the first to sixth aspects of the present invention, the semiconductor chips can be quickly supplied to the bonding tool of the bonding head,
The bonding cycle can be shortened.

In addition, according to the invention of claim 2,
It is possible to reduce the size and weight of the chip supply device.

In addition, according to the invention of claim 3,
It is possible to reduce the size and weight of the chip supply device and simultaneously supply a plurality of semiconductor chips.

In addition, according to the invention of claim 4,
It is possible to reduce the size and weight of the chip supply device and to supply semiconductor chips of different sizes and shapes.

In addition, according to the invention of claim 5,
It is possible to reduce the size and weight of the chip supply device and shorten the moving distance of the chip slider.

In addition, according to the invention of claim 6,
It is possible to reduce the size and weight of the chip supply device and shorten the moving distance of the chip slider, and to quickly move the chip slider to the chip passing position.

[Brief description of drawings]

FIG. 1 is a perspective view of a bonding head mounting portion.

FIG. 2 is a front view showing the overall configuration of a chip bonding apparatus.

FIG. 3 is a perspective view showing a positioning mode of a vacuum suction holding portion of a semiconductor chip.

FIG. 4 is a perspective view of a chip supply device.

FIG. 5 is a right side view of FIG.

FIG. 6 is a perspective view showing another example of a bonding head.

[Explanation of symbols]

 1 semiconductor chip 2 chip slider 2a chip holding part 3 bonding tool 4 bonding head 7 rail 25 chip supply device 28 bonding tool B bonding position C temporary stop position D chip supply position E chip passing position

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Hashimoto 1-45 Oe 1-chome Otsu Shiga Prefecture Toray Engineering Co., Ltd.

Claims (6)

[Claims] 1. A bonding head mounted so that a bonding tool capable of vacuum-holding a semiconductor chip can be moved up and down is mounted so that it is always positioned at a bonding position, and the bonding head is moved to a standby position. A chip bonding apparatus equipped with a chip supply device for transferring a semiconductor chip to a chip passing position below a lower end of a tool. 2. The chip supply device is provided with a chip slider mounted so as to be guided and moved by a rail while horizontally holding a chip holder for holding a semiconductor chip. The chip bonding apparatus according to. 3. The chip bonding apparatus according to claim 2, wherein the chip holding portion of the chip slider is configured to hold a plurality of semiconductor chips. 4. The chip bonding apparatus according to claim 2, wherein the chip holding portion of the chip slider is configured to hold the semiconductor chip by vacuum suction. 5. The chip slider according to claim 2, wherein the chip slider is mounted so as to be capable of reciprocating between a chip feeding position where a semiconductor chip is fed to the chip holding portion and a chip passing position. Chip bonding equipment. 6. A chip slider is moved from a chip supply position to a temporary stop position close to a bonding head during bonding, and then can be moved to a chip passing position when a bonding tool is moved to a standby position. The chip bonding apparatus according to claim 5, wherein the chip bonding apparatus is mounted on the chip bonding apparatus.