JP3381910B2 - Wire bonding equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a wire bonding apparatus. In particular, the present invention relates to a wire bonding apparatus that blows electric sparks to the tip of a wire by electric discharge to form a ball.

[0002]

2. Description of the Related Art FIG. 4 shows an example of a commonly used wire bonding apparatus. In the figure, 1 is a wire made of a conductive material such as gold, 2 is a wire 1, and 2 is a wire.
Capillary 3 movable in the vertical and horizontal directions is a torch rod 3 which discharges electric sparks at the tip of the wire 1 led out from the capillary 2 to form a ball 1a, and 4 is a semiconductor chip such as an IC to be bonded with the wire 1. ,
5 is a substrate also provided with a pad to be bonded with the wire 1, 6 is a stage made of metal such as stainless steel on which the substrate 5 on which the semiconductor chip 4 is placed, 7 is abutted on the upper surface of the substrate 5, and the stage 6 and the substrate A holding member made of metal such as stainless steel for holding 5 is a heater unit, and 9 is a screw for fixing the stage 6 to the heater unit 8.

Next, the operation will be described. First,
A ball 1a is previously formed on the tip of the wire 1 extending from the capillary 2. Next, the capillary 2 is lowered by the head up-and-down drive mechanism, and the ultrasonic waves oscillated from the ultrasonic oscillator 11 and pressure are applied via the ultrasonic horn 10 provided on the capillary 2 to perform connection by ball bonding. The ball 1a and the electrode of the semiconductor chip 4 are bonded to the electrode of the semiconductor chip 4. Next, the capillary 2
Rises by a certain amount, moves by a certain amount in the plane direction, then descends, and is connected by applying pressure and ultrasonic waves oscillated from the ultrasonic oscillator 11 via the ultrasonic horn 10 provided in the capillary 2. Thus, the wire 1 is bonded to the electrode of the substrate 5. Next, after the capillary 2 is lifted by a certain amount, the wire 1 is held and lifted by a clamper (not shown), and the wire 1 is ruptured from the wire portion bonded to the electrode portion of the substrate 5, and the semiconductor chip 4 and the substrate 5 are separated. The connection by wire 1 is completed. Then, in preparation for the next connection of the wire 1, electric sparks are blown from the torch rod 3 to the tip of the wire 1 coming out of the capillary 2 by discharge to form a ball 1a.

[0004]

However, the wire 1 is not always connected to the semiconductor chip 4 or the substrate 5 with certainty. For example, as shown in the drawing, the wire 1 is connected to the semiconductor chip 4. When the connection to the substrate 5 fails, electric sparks fly to the wire 12 that has failed to connect, and the electricity transmitted from the wire 12 is transferred to the semiconductor chip 4, the substrate 5, and the holding member 7, or the semiconductor chip 4, the substrate. 5, substrate 5
Excessive electricity flows to the semiconductor chip 4 by being transmitted to the through hole 5a formed in and the stage 6,
Since the semiconductor chip 4 is destroyed, the semiconductor chip 4 becomes a defective product.

Further, even when the wire 1 is reliably connected to the semiconductor chip 4 and the substrate 5, the wire 1 is cut from the portion connected to the substrate 5 during the bonding work to the substrate 5, for example, and thus the capillary is obtained. In some cases, when the wire 2 is pulled up, the wire 1 is also pulled up at the same time, and the wire 1 is not located at the tip of the capillary 2. In the case where the wire 1 is not located at the tip of the capillary 2 as described above, electric sparks due to the discharge from the torch rod 3 fly to the wire 1 that is normally connected, and as described above,
Excessive electricity flows to the semiconductor chip 4 and the semiconductor chip 4
Therefore, the semiconductor chip 4 becomes a defective product.

Even when the wire 1 is securely connected, the discharge from the torch rod 3 is not always applied to the tip of the wire 1 extending from the capillary 2, and the discharge is generated at the tip of the wire 1 extending from the capillary 2. In this case, the ball 1a may be attached to the wire 1 during the next operation.
There was a problem that was not formed.

The present invention prevents discharge to an object to be bonded such as a semiconductor chip and prevents occurrence of defects in the object to be bonded. Moreover, it aims at providing the wire bonding apparatus which can perform stable bonding work.

[0008]

SUMMARY OF THE INVENTION According to the present invention, a capillary for guiding a wire, a torch rod for ejecting electric sparks to form a ball at the tip of the wire drawn out of the capillary, and a wire bonded by the wire. In a wire bonding apparatus including a stage on which a bonding object is placed and a holding member that holds the object to be bonded by the stage, the stage and the holding member are covered with an insulating member.

Further, a capillary for leading out the wire, a torch rod for forming a ball by flying electric sparks at the tip of the wire led out from the capillary, and a stage for mounting an object to be bonded by the wire. A wire bonding apparatus having a holding member for holding the object to be bonded with the stage, wherein at least a portion of the stage on which the object to be bonded is placed is covered with an insulating member and at least the object to be bonded of the holding member. The part that comes into contact with an object is covered with an insulating member.

Further, a capillary for guiding the wire, a torch rod for forming a ball by flying electric sparks at the tip of the wire led out of the capillary, and a stage for mounting an object to be bonded by the wire. A wire bonding apparatus including a holding member for holding the object to be bonded with the stage, wherein the stage is formed of an insulating member and the holding member is covered with an insulating member.

Further, a capillary for leading out the wire, a torch rod for forming a ball by flying an electric spark at the tip of the wire led out from the capillary, and a stage for mounting an object to be bonded by the wire. In a wire bonding apparatus including a holding member that holds the object to be bonded with the stage, the stage is formed of an insulating member, and at least a portion of the holding member that is in contact with the object to be bonded is covered with an insulating member. It is a thing.

The insulating member forming the stage is made of ceramic.

A lightning rod is provided near the torch rod.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION A wire bonding apparatus according to the present invention comprises a capillary 2 for leading a wire 1 and a torch rod 3 for forming a ball 1a by flying an electric spark at the tip of the wire 1 led out of the capillary 2. In a wire bonding apparatus including a stage 6 on which a semiconductor chip 4 or a substrate 5 to be bonded by the wire 1 is placed, and a holding member 7 for holding the semiconductor chip 4 or the substrate 5 on the stage 6. The stage 6 and the holding member 7 are covered with insulating members 13 and 14.
With this configuration, it is possible to prevent discharge to an object to be bonded such as the semiconductor chip 4 and the substrate 5 through the wire that has failed to be bonded, and it is possible to prevent a defect in the object to be bonded from occurring. . In addition, when the wire 1 is securely connected, it is possible to reliably generate an electric discharge between the wire 1 and the torch rod 3,
Stable bonding work can be performed.

Further, a capillary 2 for leading out the wire 1
Then, a torch rod 3 for forming an electric spark to form a ball 1a, a semiconductor chip 4 and a substrate 5 to be bonded by the wire 1 are placed on the tip of the wire 1 led out from the capillary 2. Stage 6
And a holding member 7 that holds the semiconductor chip 4 and the substrate 5 with the stage 6, a portion 6a of the stage 6 on which at least the substrate 5 is mounted.
Is covered with an insulating member 13, and at least a portion 7a of the holding member 7 that contacts the substrate 5 is covered with an insulating member 14. With this configuration, it is possible to prevent discharge to an object to be bonded such as the semiconductor chip 4 and the substrate 5 through the wire that has failed to be bonded, and it is possible to prevent a defect in the object to be bonded from occurring. .
If the wire 1 is securely connected, the wire 1
A discharge can be reliably generated between the torch rod 3 and the torch rod 3, and a stable bonding operation can be performed.

Further, a capillary 2 for leading out the wire 1
Then, a torch rod 3 for forming an electric spark to form a ball 1a, a semiconductor chip 4 and a substrate 5 to be bonded by the wire 1 are placed on the tip of the wire 1 led out from the capillary 2. Stage 6
And a holding member 7 for holding the semiconductor chip 4 and the substrate 5 with the stage 6, the stage 6 is formed of an insulating member, and the holding member 7 is covered with the insulating member 14. With this configuration, it is possible to prevent discharge to an object to be bonded such as the semiconductor chip 4 and the substrate 5 through the wire that has failed to be bonded, and it is possible to prevent a defect in the object to be bonded from occurring. . Further, when the wire 1 is securely connected, the electric discharge can be surely generated between the wire 1 and the torch rod 3, and the stable bonding work can be performed.

Further, a capillary 2 for leading out the wire 1
Then, a torch rod 3 for forming an electric spark to form a ball 1a, a semiconductor chip 4 and a substrate 5 to be bonded by the wire 1 are placed on the tip of the wire 1 led out from the capillary 2. Stage 6
And a holding member 7 that holds the semiconductor chip 4 and the substrate 5 with the stage 6, the stage 6 is formed of an insulating member, and at least a portion 7a of the holding member 7 that contacts the substrate 5 is insulated. Member 1
It is covered with 4. With this configuration, it is possible to prevent discharge to an object to be bonded such as the semiconductor chip 4 and the substrate 5 through the wire that has failed to be bonded, and it is possible to prevent a defect in the object to be bonded from occurring. . Further, when the wire 1 is securely connected, the electric discharge can be surely generated between the wire 1 and the torch rod 3, and the stable bonding work can be performed.

The insulating member forming the stage 6 is made of ceramic. With this configuration, it is possible to prevent discharge to an object to be bonded such as the semiconductor chip 4 and the substrate 5 through the wire that has failed to be bonded, and it is possible to prevent a defect in the object to be bonded from occurring. . Further, when the wire 1 is securely connected, the electric discharge can be surely generated between the wire 1 and the torch rod 3, and the stable bonding work can be performed. It also has excellent wear resistance,
It is possible to provide a wire bonding apparatus including a stage having good durability.

A lightning rod 16 is provided near the torch rod 3.
Is provided. With this configuration,
Semiconductor chip 4 through the wire that failed in bonding
It is possible to prevent electric discharge to an object to be bonded such as the substrate 5 and the substrate 5, and prevent occurrence of a defect in the object to be bonded.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIG. The same or corresponding portions as those of the conventional example are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, 1 is a wire, 2 is a capillary, 3 is a torch rod, 4 is a semiconductor chip, 5 is a substrate,
6 is a stage, 7 is a holding member, 8 is a heater unit, 9
Is a screw, and 13 and 14 are insulating members.

In the present embodiment, the semiconductor chip 4 and the substrate 5 are objects to be bonded by a bonding apparatus, but a lead frame or the like may be used instead of the substrate 5.

The stage 6 can be moved up and down together with the heater unit 8 by a driving means (not shown) with the semiconductor chip 4 and the substrate 5 placed on the upper surface thereof. The holding means 7 is the substrate 5 placed on the ascending stage 6.
The upper surface of the substrate 5 between the stage 6 and
Is to hold.

Conventionally, the stage 6 and the holding member 7 were exposed as shown in FIG. 4, but in the present embodiment, the surfaces of the stage 6 and the holding member 7 are insulating members. Adhesive tape 13 made of fluorinated ethylene resin,
14 is attached and covered.

As described above, since the stage 6 and the holding member 7 are covered with the adhesive tapes 13 and 14 made of tetrafluoroethylene resin, which is an insulating member, the wire 12 in which the discharge from the torch rod 3 fails in the bonding. It does not occur and is not discharged to the semiconductor chip 4 or the substrate 5 through the wire 12, so that the semiconductor chip 4 or the substrate 5 can be prevented from being damaged, and the occurrence of defects can be prevented. When the wire 1 is securely connected to the bonding, the ball 1a can be formed by discharging the wire 1 to the tip of the wire 1 without being discharged to the tip of the wire 1 and to be stable. Bonding work can be performed.

In the above-described embodiment, the adhesive tapes 13 and 14 made of tetrafluoroethylene resin are used as the insulating member, but the stage 6 is made of a film made of an insulating member such as ethylene tetrafluoride resin or ceramic. The holding member 7 may be covered. Further, other materials may be heat-resistant hard rubber, heat-resistant plastic, or the like.

Further, in the above-mentioned embodiment, the entire surfaces of the stage 6 and the holding member 7 are covered with the insulating member, but as shown in the second embodiment of FIG. 2, the semiconductor chip 4 and the substrate 5 of the stage 6 are mounted. The portion 7a to be placed and a part of the side surface of the stage 6 may be covered with the insulating member 13. In addition, at least the portion of the holding member 7 that contacts the substrate 5 may be covered with the insulating member 14. Although not shown, only the portion 7a of the stage 6 on which the semiconductor chip 4 and the substrate 5 are mounted may be covered with the insulating member 13.

Next, a third embodiment of the present invention will be described. In this embodiment, a lightning rod 15 is provided near the torch rod 3. The position where the lightning rod 15 is provided is such that when the capillary 2 moves in the vertical and horizontal direction to form the ball 1a, the lightning rod 15 moves from the torch rod 3 to the torch rod 3.
The distance L1 to the tip of the wire 1 (position of the ball 1a) which is derived from the capillary 2 and should be in a predetermined position in advance.
From the torch rod 3 to the torch rod 3, and is closer to the torch rod 3 from the to-be-bonded object, the tip of the capillary 2, and other members such as the holding member 7. That is, the relationship of distance is L2 <L
1 <L3.

With this configuration, when there is no wire 1 having a predetermined length at the tip of the capillary 2 and no discharge is made at the tip, electric sparks due to discharge from the torch rod 3 are other than the wire 1 at the tip of the capillary 2. Since the lightning rod 15 is discharged without being generated, it is possible to prevent the semiconductor chip 4 and the substrate 5 from being damaged. Further, if the tip 12a of the wire 12 that has failed to be bonded is the lightning rod 1
Even if it is located at a position closer to the torch rod 3 than the distance L1 from 5 as shown in the first and second embodiments,
By providing the insulating members 13 and 14 on the stage 6 and the holding member 7, the object to be bonded such as the semiconductor chip 4 and the substrate 5 is not discharged through the wire 12, and the object to be bonded is prevented from being damaged. be able to.

Although the stage 6 is covered with the insulating member 13 in each of the above embodiments, the stage 6 itself may be formed with an insulating member instead of being covered with the insulating member 13. In particular, since the object to be bonded moves on the stage 6, a material having high wear resistance is preferable, and for example, the insulating member may be made of ceramic having high wear resistance.

If the screw 9 is also made of a heat-resistant synthetic resin having an insulating property, the insulating property of the stage 6 is enhanced,
It is possible to prevent the semiconductor chip 4 and the substrate 5 from being damaged. Further, by reliably discharging the tip of the wire 1, the ball 1a can be formed and a stable bonding operation can be performed.

[0032]

As described above, according to the present invention, it is possible to achieve the initial purpose, prevent discharge to an object to be bonded such as a semiconductor chip, and prevent occurrence of defects in the object to be bonded. Further, it is possible to provide a wire bonding apparatus that can perform stable bonding work.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention.

FIG. 2 is a sectional view of a second embodiment of the present invention.

FIG. 3 is a sectional view of a third embodiment of the present invention.

FIG. 4 is a sectional view of a conventional example.

[Explanation of symbols]

1 wire 1a ball 2 capillaries 3 torch rod 4 Semiconductor chip (object to be bonded) 5 Substrate (object to be bonded) 5a through hole 6 stages 7 Holding member 12 wires 13,14 Insulation member 15 lightning rod

Claims (6)

(57) [Claims] 1. A capillary for drawing out a wire, a torch rod for forming a ball by flying electric sparks at the tip of the wire drawn out from the capillary, and a stage for mounting an object to be bonded by the wire. A wire bonding apparatus including a holding member that holds the object to be bonded with the stage,
A wire bonding apparatus characterized in that the stage and the holding member are covered with an insulating member. 2. A capillary for drawing out a wire, a torch rod for forming a ball by flying an electric spark at the tip of the wire drawn out from the capillary, and a stage for mounting an object to be bonded by the wire. A wire bonding apparatus including a holding member that holds the object to be bonded with the stage,
A wire bonding apparatus, characterized in that at least a portion of the stage on which the object to be bonded is placed is covered with an insulating member, and at least a portion of the holding member that comes into contact with the object to be bonded is covered with an insulating member. 3. A capillary for drawing out a wire, a torch rod for forming a ball by flying electric sparks at the tip of the wire drawn out from the capillary, and a stage for mounting an object to be bonded by the wire. A wire bonding apparatus including a holding member that holds the object to be bonded with the stage,
A wire bonding apparatus, wherein the stage is formed of an insulating member and the holding member is covered with an insulating member. 4. A capillary for drawing out a wire, a torch rod for forming a ball by flying electric sparks at the tip of the wire drawn out from the capillary, and a stage for mounting an object to be bonded by the wire. A wire bonding apparatus including a holding member that holds the object to be bonded with the stage,
A wire bonding apparatus, wherein the stage is formed of an insulating member, and at least a portion of the holding member that comes into contact with the object to be bonded is covered with an insulating member. 5. The insulating member forming the stage is made of ceramic.
The wire bonding apparatus described. 6. The wire bonding apparatus according to claim 1, further comprising a lightning rod provided near the torch rod.