JPS61281533A - Wire bonding device - Google Patents

Abstract

PURPOSE:To obtain a wire bonding device capable of keeping the shape of wire loop uniform by providing a wire guide to keep the position of wire consistent on the clamper section of a wire bonding device having a tension-applying mechanism and a clamper. CONSTITUTION:A wire 4 is released from a spool arranged upward and enters to a wedge hole 6 on a wedge 2 through a guide hole 5 provided on a horn 3. A tension-applying mechanism 8, which injects air flow 7 to the wire 4 from the upper side to the lower side and applies tension to the wire, is arranged on the upper section of the horn 3. A clamper 10 consisting of a pair of claws 9 that clamp the wire 4 is arranged near the wedge 2 to push the end of the wire 4 into the wedge hole 6 in clamping the wire 4. The wire guide 9 restricts upper and lower directional position of the wire 4 with its extended section intersecting the wire at right angles.

Description

[Detailed description of the invention] 〔Technical field〕 .

The present invention relates to a wire bonding device.

[Background technology]

As a wire bonding device, for example, "Monthly Semiconductor World" published by Press Jaror Co., Ltd.
d) Many models have been developed as described in J November 1982 issue, October 15, 1982, pages 40 to 45. Further, as described in the same document, important requirements for wire bonding equipment are good bondability and good wire shape (loop shape) after bonding. As one method for improving this wire loop shape, for example, Japanese Patent No. 93204
As described in Japanese Patent No. 4, a method is known in which wire bonding is performed while applying tension to the wire by blowing air from the side onto the wire while it is being supplied.

On the other hand, even in the ultrasonic wedge bonding method, the method of applying tension to the wire is important because it influences the loop shape of the wire when moving to the second bonding position after the first bonding is completed.

However, the inventors have found that this method may deteriorate bonding properties due to the following reasons. In other words, when the clamper clamps the wire, the air used to apply tension to the wire is
Allowing the wire to swing - The wire feeding angle cannot be maintained uniformly, causing variations in pig till.

Furthermore, since the size and angle of the wedge hole through which the wire passes differs depending on the product to be bonded, the angle at which the clamper feeds the wire is not necessarily the same. That is,
If the angle of the wedge hole and the angle of the clamper operation are different, the pig till may vary due to the escape of the wire. If such pigtil variation is short, the width of the crimped part of the wire becomes large, resulting in a defective shape (large crimped width), and if it is long, the pigtil may protrude from the bonding area and cause bonding to the semiconductor element area. Electrical short circuit with Pasodo area, i.e.
This may cause complete failure of Asiodo, etc. Additionally, as mentioned above, when the wedge moves from the first bonding position to the second bonding position, depending on the direction in which the wire extends, the wire may be squeezed by the wedge hole, causing damage and reducing bonding reliability. There are cases where it happens.

[Purpose of the invention]

゛・゛An object of the present invention is to provide a wire bonding device that can maintain a constant wire loop shape.

Another object of the present invention is to provide a wire bonding device that can always keep the pig till length constant.

Another object of the present invention is to provide a wire bonding device that can perform wire bonding without damaging the wire.

Another object of the present invention is to provide a wire bonding device that can freely control the wire loop shape.The above and other objects and novel features of the present invention are as follows:
Perforation 6710. from the description of this specification and the accompanying drawings. . 7
Ah practice.

[Summary of the Invention] A brief overview of typical inventions disclosed in this application is as follows.

That is, the wire pounding device of the present invention has a clamper section that supplies a tensioned wire with air and a wire guide that forces the wire so that the wire is always at a constant pMH. is provided, and the wire is supplied in a predetermined state not only during the first bonding and the second bonding, but also when moving from the first bonding position to the second bonding position. The wire loop shape becomes a desired shape, the length of the pigtail is constant, and the wire is not damaged, so the reliability and yield of bonding are improved. In addition, by controlling the strength of the wire tension, the height of the wire loop shape can be adjusted. [Embodiment] FIG. 1 is a schematic diagram showing the main parts of a wire bonding part in a wire bonding apparatus according to an embodiment of the present invention.
The second tooth is a side view showing the brush bar and the d-wire guide, Figure 3 is a cross-sectional view showing the state of the wire when the wedge is moving, and Figure 4 is the state of the wire when the wedge is moving without a wire guide. 5 is a sectional view showing the wire being fed out, FIG. 6 is a sectional view showing the wire being fed out without a wire guide,
7 to 14 show a series of operating systems showing wire bonding by the wire bonding device of the invention, FIG. 8 is a schematic diagram showing the wedge etc. located above the first bonding position, and FIG. Fig. 9 is a schematic diagram showing the first bonding state, Fig. 10 is a schematic diagram showing the first wedge rising state, Fig. 11 is a schematic diagram showing the wedge horizontal movement state, and Fig. 12 is a schematic diagram showing the second bonding state. figure,'
Fig. 13 is a schematic diagram showing the state of wire cutting, Fig. 14 is a schematic diagram showing the state of proceeding to the next wire bonding, and Fig. 15 is a schematic diagram showing the state of wire bonding.
The figure is a sectional view showing the operation of the wire and wire guide.

The wire pondin multi-device of this embodiment includes a rotatable stage 1, a wedge 2 located directly above the stage 1, a wedge 2 held at the tip, and
A bone 3 has a built-in vibrator for ultrasonic vibration of the wedge 2, and a bone 3 that supports the other end of the horn 3 and whose vertical movement can be controlled and whose movement can be controlled along the extending direction of the horn 3. A wire 4 made of aluminum is unwound from a spool disposed above (not shown), passes through a guide hole 5 provided in the horn 3, and passes through a wedge hole 6 of the wedge 2. Further, a tension applying mechanism 8 is disposed above the horn 3 to apply tension to the wire 4 by blowing an air flow 7 onto the wire 4 from diagonally upward to downward. Also, in the vicinity of the wedge 2, as shown in FIG.
0 is provided, and when the wire 4 is clamped, the tip of the wire 4 is pushed into the wedge hole 6, thereby forming a wire supply mechanism. Furthermore, wire guides 11 are disposed at the upper and lower portions of one claw body 9 of the clamper 10. This wire guide 11 is configured to restrict the lower position of the wire 4 at the upper side in order to prevent the wire 4 from swinging in the vertical direction in response to the air flow 7 extending diagonally from above to below.
In the lower part, the upper position of the wire 4 is regulated. The wire guide 9 is configured to restrict the vertical position of the wire 4 at a portion extending perpendicularly to the wire 4.

In such an ultrasonic wire bonding device,
After placing an IC substrate 12 such as the base of a ceramic package on the stage 1, electrodes (not shown) of a semiconductor element (chip) 14 fixed on the metallized layer 13 on the main surface of the substrate 12 are placed on the stage 1. Wire bonding is performed between this portion and the corresponding inner end portion of the metallized layer 15 on the main surface of the substrate 12 or the inner end portion of the lead 16. At this time, prior to tensioning the wire, the stage 1 is rotationally controlled so that the direction in which the wire is tensioned matches the direction in which the horn 3 extends. Then, by the vertical and horizontal movement of the edge 2 and the ultrasonic alligator movement, the first bonding to the electrode portion of the chip 14 and the lead 1 are performed.
Second bonding is performed to the inner end portion of 6, and wire bonding is performed to the electrode holder 116.

Next, the syer bonding operation will be explained with reference to FIGS. 7 to 14A. Note that these figures are schematic diagrams, and the wire guide 11 for regulating the position of the wire 4 is omitted.

The wedge 2 first faces above a predetermined electrode of the chip 14, as shown in FIG. Thereafter, as shown in FIG. 8, the clamper 10, which is a wire supply mechanism, clamps the wire 4 and moves forward by a predetermined distance, so that the tip of the wire 4 protrudes below the crushing surface of the wedge 2. Do it like this.

Next, as shown in FIG. 9, the wedge 2 is lowered to press the tip of the wire 4 against the unillustrated electrode of the tube 14 with the crushing surface at the lower end of the wedge 2, and to generate ultrasonic vibrations. to fix the tip of the wire 4 to the electrode.

Next, as shown in FIG. 10, the clamper 1o that had clamped the wire 4 is opened and the wire 4 is unclamped. Thereafter, the wedge 2 rises and moves horizontally (the horn 3 retreats) to reach the second bonding position, which is the lead 16.
Move the inner edge upwards. At this time, the wires 4 that are sequentially let out from the edge hole 6 of the wedge 2 are constantly applied with a predetermined tension by the tension applying mechanism 8 as described above, and are swayed in the vertical direction due to the application of this tension. Said Wai! 4 is the wire guide 11
It is regulated to eliminate vertical shaking. As a result, as shown in FIG. 3, the wire 4 is fed at a predetermined angle with respect to the wedge hole 6 of the wedge 2, and is in a natural state within the wedge hole 6. The wire 4 is fed out smoothly, and due to the smooth feeding of the bracket, the wire 4 is fed out with a predetermined tension at all times. therefore,
As shown in FIG. 12, the loop shape of the wire 4 connecting the first bonding part and the second bonding part becomes a preferable shape, and chip short-circuits and the like due to the fall of the wire do not occur.

In addition, as shown in FIG. 4, the wire 4 is not squeezed strongly by the edge of the wedge hole 6, unlike in the case where the wire guide 11 is not provided, so the surface of the wire 4 is not damaged. The reliability of the wire is also increased.

Next, as shown in FIG. 12, when the clamper 10 is opened and the wire 4 is unclamped, the wedge 2 vibrates ultrasonically and the part of the wire 4 that contacts the second bonding part is connected to the second bonding part. It is connected to the lead 16 which is the part.

Next, as shown in FIG. 13, the clamper 10
clamps the wire 4 again, pulls the clamped wire 4 diagonally upward, and breaks the wire 4 at the second bonding portion.

At this time, the wire 4 is connected to the wire guide 11 as described above.
It is regulated to eliminate vertical shaking. As a result, as shown in FIG. 5, the wire 4 is fed at a predetermined angle to the wedge hole 6 of the wedge 2, so that it is in a natural state within the wedge hole 6.
As shown in FIG. 6, unlike when the wire guide 11 is not provided, the wire 4 is not squeezed strongly by the upper or lower edge of the wedge hole 6, so the wire 4 always breaks at the desired position. This prevents the length of the pig till from becoming longer or shorter, and prevents short-circuits (area shorts) caused by the pig till extending beyond the bonding area due to the longer length of the pig till. It is possible to prevent poor shape of the crimped portion (large crimped width) caused by the shortening of the length.

Next, as shown in FIG. 14, as the wedge 2 rises, the substrate 12 moves to the next wire tensioning position by controlling the rotation of the stage 1 (not shown in the figure), and the -th wire bonding period is completed. do.

〔effect〕

(1) The wire bonding device of the present invention comprises ° wire 4
Since the tension is applied by the tension applying mechanism 8 using the air flow 7 to the wire 4,
is swayed by the air flow 7, but the wire guide 11 restricts the sway of the wire 4, and the wire 4 is fed so as to always maintain a constant angle with respect to the wedge hole 6 of the wedge 2. The advantage is that the wire is not squeezed at the tL6 portion of the sea urchin, and the wire can be fed smoothly. □(2) According to (1) above, the wire bonding apparatus of the present invention allows the wire 4 to be smoothly fed out from the wedge hole 6, so that a constant tension is always applied to the wire 4, and the loop shape of the wire is Since it is always formed in a good condition, the reliability of bonding is improved.

(3) From the above (11), in the wire bonding apparatus of the present invention, the wire 4 is not squeezed by the upper edge or the lower edge of the wedge hole 6, and the cutting position of the wire is also constant, so the pig tilt The length is always constant and good, and the occurrence of short-circuit defects due to being too long is suppressed. □Problems in the shape of the crimped part due to being too short are also suppressed, improving bonding yield and reliability. This effect can be obtained.

(3) From the above (11), in the wire bonding apparatus of the present invention, the wire 4 is not squeezed in the wedge hole 6 portion, so the surface of the wire is not scratched, and the bonding process is improved. This has the effect of improving reliability.

(4) According to the above (1) to (31), according to the wire bonding apparatus of the present invention, a synergistic effect can be obtained in that the bonding cost can be reduced by improving the reliability of wire bonding and improving the yield. □ (5 ) Another effect is that the wire 4 can be kept at a constant level by adjusting the amount of contact of the wire guide 11 with the wire 4, as shown in FIG. The effect is that low load or high load can be applied, and the loop shape (high or low) can be adjusted.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the above Examples and can be modified in various ways without departing from the gist thereof. Nor.

[Application field]

In the above description, the invention made by the present inventor is mainly applied to the manufacturing technology of semiconductor devices, which is the background field of application, but the invention is not limited thereto.

The present invention can be applied to any technology that connects at least two points with a wire.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the main parts of the wire bonding part in a wire bonding apparatus according to an embodiment of the present invention, FIG. 2 is a side view showing a clamper and a wire guide, and FIG. 3 is a schematic diagram showing the wire during wedge movement. Figure 4 is a cross-sectional view showing the state of the wire when the wedge moves without a wire guide, Figure 5 is the same (cross-sectional view showing the wire feeding state, Figure 6 is the wire guide) 7 is a schematic diagram showing a state in which wire bonding is started by the wire bonding apparatus of the present invention, and FIG. 8 similarly shows a wedge etc. located above the first bonding position. Figure 9 is a schematic diagram showing the first bonding state, Figure 10 is a schematic diagram showing the wedge rising state, Figure 11 is a schematic diagram showing the wedge horizontally moving state, and Figure 12 is the same diagram showing the second bonding state. A schematic diagram showing the state, Fig. 13 is a schematic diagram showing the wire cutting state, Fig. 14 is a schematic diagram showing the wire cutting state.
This figure is also a schematic diagram showing the state of moving on to the next wire bonding, and FIG. 15 is a sectional view similarly showing the operation of the wire guide and wire.

Claims (1)

[Claims] 1. A wedge that crushes the tip of the wire, a wire supply mechanism that supplies the wire to the wedge hole of this wedge, a tension adding mechanism that applies tension to the wire, and a clamper that clamps the wire near the wedge. 1. A wire bonding device comprising: a wire guide provided in the clamper portion to keep the wire in a constant position at all times.