JP3355987B2 - Wire bonding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire bonding apparatus for connecting a substrate and a chip on the substrate with wires.

[0002]

2. Description of the Related Art A wire bonding apparatus for connecting a substrate and a chip on the substrate with a wire generates an electric spark between a lower end of the wire inserted into a capillary tool and a needle-like electrode (torch). The ball formed at the lower end of the wire is pressed against the electrode of the chip for bonding.

FIG. 4 is a perspective view of a torch unit of a conventional wire bonding apparatus. 1 is a needle electrode,
Except for its tip, it is coated with the insulating film 2. The needle electrode 1 is inserted into the lower end of the frame 3, and the rear end is connected to a power cord 5 by a connector 4. Reference numeral 6 denotes a capillary tool, and reference numeral 7 denotes a wire inserted through the capillary tool 6. An electric spark is generated at the lower end of the needle-shaped electrode 1 and the wire 7 to form a ball 7a at the lower end of the wire 7, and the ball 7a is pressed against the electrode 10 of the chip 9 on the substrate 8 for bonding.

When the electric spark is repeatedly generated, the tip a of the needle electrode 1 is gradually worn, and when the insulating film 2 is partially peeled off, the electric current is generated between the peeled portion and the lower end of the wire 7. Needle electrode 1 must be replaced as appropriate, since a target spark is erroneously generated. Needle electrode 1
And the frame 3 and the connector 4 are integrally assembled. Therefore, conventionally, the entire torch unit including the needle-shaped electrode 1, the frame 3 and the connector 4 is integrally removed from the wire bonding apparatus, and a new torch unit is provided. Was attached to a wire bonding apparatus.

[0005]

In a wire bonding apparatus, the positional accuracy of the tip a of the needle-shaped electrode is extremely important.
A normal electrical spark cannot be generated between the lower end of the electric spark. In the prior art, the needle-shaped electrode 1 and the first frame 3 are assembled as a single body. Therefore, the positional accuracy of the tip end portion a of the needle-shaped electrode 1 is determined by attaching the first frame 3 to the mounting portion 16 of the wire bonding apparatus. Determined by positional accuracy.

However, in the above-described conventional structure, it is difficult to secure the mounting position accuracy of the frame 3, and therefore, the position of the distal end portion a of the needle electrode 1 is likely to be out of order. In addition, since the entire torch unit including the frame 3 and the connector 4 has to be completely replaced, there is a problem that the replacement work is not only troublesome but also increases the cost.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a wire bonding apparatus having a torch unit which can easily replace a needle electrode and can secure a high positional accuracy of the tip of the needle electrode. .

[0008]

SUMMARY OF THE INVENTION According to the present invention, an electric spark is generated between a horn holding a capillary tool and a lower end of a wire inserted into the capillary tool to form a ball at the lower end. What is claimed is: 1. A wire bonding apparatus comprising: a torch unit; and a moving table for horizontally moving the capillary tool and the torch unit relative to a substrate, wherein the torch unit is coupled to a mounting body on the moving table. And a rod-shaped insulator detachably mounted in a mounting opening opened at a lower end portion of the frame, and a needle-shaped insulator removably inserted into a center hole formed in a longitudinal direction of the rod-shaped insulator. Electrodes and rods
Jo of being connected to the rear end portion of the insulator consist of the rod-like insulator is brought into contact with the rear end of the needle electrode projecting from the rear end of <br/> Ru connector power cord.

[0009]

According to the present invention having the above-described structure, the needle-shaped electrode can be easily replaced by simply inserting and removing it from the insulator.
In addition, since the positional accuracy of the distal end of the needle electrode is substantially determined by the mounting positional accuracy of the frame with respect to the mounting body, if the processing accuracy and the mounting positional accuracy of the frame are secured, the high accuracy of the distal end of the needle electrode can be achieved. Position accuracy can be ensured.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a wire bonding apparatus according to an embodiment of the present invention, FIG. 2 is an exploded view of the torch unit, and FIG. 3 is a sectional view of the torch unit.

First, the overall structure of the wire bonding apparatus will be described with reference to FIG. Reference numeral 21 denotes a capillary tool, which is held at the tip of a horn 22. The capillary tool 21 has a wire 2 drawn out from a spool 23.
4 is inserted. 25 is a clamper for clamping the wire 24. The base end of the horn 22 is the drive unit 2
6 is held. When the drive unit 26 is driven,
The horn 22 moves up and down. Reference numeral 27 denotes a mounting body, and the mounting body 27 and the drive unit 26 are installed on a moving table 28. A transport path 29 transports the substrate 30. The torch unit 3 is on the side of the capillary tool 21
1 is provided. When the moving table 28 is driven,
The capillary tool 21 and the torch unit 31
Moves horizontally relative to.

Next, the structure of the torch unit 31 will be described with reference to FIGS. Numeral 32 denotes a rod-shaped insulator made of ceramic or the like. A center hole 33 is drilled in the longitudinal direction of the insulator 32, and a needle-like electrode (torch) 34 is removably inserted into the center hole 33. 3
Reference numeral 5 denotes an inverted L-shaped frame, the upper end of which is connected to the front surface of the mounting body 27. The lower end of the frame 35 is a split part 36, and a mounting port 37 is opened at the upper end of the split part 36. The insulator 32 is inserted into the mounting opening 37, and a screw 39 is inserted into the screw hole 38 and the split portion 36 is tightened, so that the insulator 32 is detachably mounted on the mounting opening 37. Reference numeral 40 denotes a connector, to which a power cord 41 is connected. As shown in FIG. 3, the connector 40 is connected to the rear end of the insulator 32 mounted on the mounting port 37. The rear end of the needle electrode 34 projects rearward from the rear end of the insulator 32 and
1 is in contact. Reference numeral 42 denotes a stop screw, and the connector 4
The connector 40 is detachably connected to the rear end of the insulator 32 by being screwed into the lower surface of the connector 0. 3, reference numeral 43 denotes a chip mounted on the substrate 30; 44, an electrode on the upper surface of the chip 43; and 45, an electrode on the upper surface of the substrate 30.

This wire bonding apparatus has the above-described configuration. Next, the handling operation will be described. In FIG. 3, by applying a voltage to the needle electrode 34, an electric spark is generated between the lower end of the wire 24 inserted into the capillary tool 21 and the tip a of the needle electrode 34, and the ball 46 is moved. Form. Next, the capillary tool 2
1 is lowered to press the ball 46 against the electrode 44 of the chip 43 for bonding. Next, the capillary tool 21
Is moved onto the electrode 45 of the substrate 30 to bond the wire 24 to the electrode 45, and the wire 24 is cut from this bonding point. By repeating the above operation, the electrode 44 of the chip 43 and the electrode 45 of the substrate 30 are connected to the wire 24.
Connect one after another.

While the voltage is applied to the needle-like electrode 34 to repeatedly form the ball 46, the tip a of the needle-like electrode 34 is worn, so the needle-like electrode 34 is replaced. This replacement is performed by extracting the needle electrode 34 from the insulator 32 and inserting a new needle electrode 34 into the center hole 33. Here, the position at which the insulator 32 is mounted on the distal end portion a of the needle electrode 34 is almost determined by the positional accuracy of the frame 35. Therefore, the working accuracy of the frame 35 and the attachment 2
If the mounting position accuracy with respect to 7 is sufficiently ensured, the position accuracy of the distal end portion a of the needle electrode 34 is sufficiently and sufficiently secured, and a stable electric spark can be generated to form the ball 46.

[0015]

According to the present invention, when the needle-shaped electrode is worn out and replaced, it is only necessary to insert and remove the needle-shaped electrode from the insulator, so that the replacement can be performed easily and quickly. In addition, if the processing accuracy of the frame and the accuracy of the mounting position on the mounting body are ensured, the position accuracy of the tip of the needle electrode can be sufficiently ensured.

[Brief description of the drawings]

FIG. 1 is a perspective view of a wire bonding apparatus according to an embodiment of the present invention.

FIG. 2 is an exploded view of a torch unit of the wire bonding apparatus according to one embodiment of the present invention.

FIG. 3 is a sectional view of a torch unit of the wire bonding apparatus according to one embodiment of the present invention;

FIG. 4 is a perspective view of a torch unit of a conventional wire bonding apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Capillary tool 22 Horn 24 Wire 27 Attachment body 28 Moving table 30 Substrate 31 Torch unit 32 Insulator 33 Center hole 34 Needle electrode 35 Frame 37 Mounting port 40 Connector 41 Power cord

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/60

Claims (1)

(57) [Claims] 1. A torch unit for generating an electric spark between a horn holding a capillary tool and a lower end of a wire inserted into the capillary tool to form a ball at the lower end, a capillary tool and a torch. A wire bonding apparatus comprising: a moving table for horizontally moving the unit relative to a substrate, wherein the torch unit includes a frame coupled to a mounting body on the moving table, and a lower end of the frame. A rod-shaped insulator detachably mounted in the opened mounting port, a needle-shaped electrode removably inserted into a central hole formed in a longitudinal direction of the rod-shaped insulator , and a rod-shaped insulator. Connected to the rear end
It is by wire bonding apparatus characterized by comprising a connector which Ru is brought into contact with the rear end of the needle electrode projecting from the rear end of the rod-like insulator power cord.