JPH0521880Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an improvement in a means for determining the length of a loop connecting bonding points of a wire bonding apparatus to reduce variations in the length of the loop.

(Prior Art) Conventionally, wire bonding equipment has always been equipped with a means for appropriately determining the length of the loop connecting bonding points (hereinafter referred to as loop length), and this has been used to perform the operation described below. is performed to determine the loop length.

FIG. 3 is an explanatory diagram of the operation of the loop length determining means of the conventional wire bonding apparatus, and the operations are performed in the order of a, b, and c in the figure.

In a of the figure, the wire 3 is fixed to the first bonding point P1, and when the cut clamp 1 is open and the capillary 2 moves, the wire 3 is connected to the capillary tip Pa and the first bonding point P1. The length connected to P1 is increasing.
Also, the distance between the tip of the capillary 2 and the lower end of the cut clamp 1 is a constant value (fixed distance D between the lower end of the cut clamp and the tip of the capillary shown in Figure 3) in any state from a to c in the figure. It is maintained.

At b in FIG. 3, the cut clamp 1 is in the closed state, and the length of the wire 3 connecting the lower end of the cut clamp 1 and the first bonding point P1 remains constant from this state onwards.

In Figure 3c, the capillary tip Pc is the second
corresponds to the bonding point of

As mentioned above, the fixed distance D between the lower end of the cut clamp 1 and the tip of the capillary remains the same between b and c in FIG. 3, and the lower end of the cut clamp 1 and the first The length of the wire 3 connecting the first bonding point P1 to the bonding point P1 is equal to the length of the wire 3 connecting the lower end of the cut clamp 1 and the first bonding point P1 in c of the figure. Therefore, the length of the wire 3 connecting the capillary tip Pc and the first bonding point P1 is
It is equal to the length connecting Pb and the first bonding point P1. That is, in c of Fig. 3, the second
The capillary tip coincides with the bonding point of
The length of the loop 5 connecting Pc and the first bonding point P1 is determined by the timing at which the cut clamp 1 closes in b of FIG. 3.

In the loop length determining means of the conventional wire bonding equipment, the tip of the capillary is
The timing at which the length of the wire 3 connecting Pb and the first bonding point P1 reaches the desired loop length has been determined empirically, and the cut clamp 1 closes at this timing, causing the loop 5 in c in FIG. The length is determined to be the desired length.

(Problem to be solved by the invention) However, in the operation of the loop length determining means of the conventional wire bonding device described above, the distance between the lower end of the cut clamp 1 and the tip of the capillary 2 is kept constant. While moving together with the capillary 2, it changes from the open state to the closed state. Therefore, it is difficult to set the length of the wire 3 connecting the lower end of the cut clamp 1 and the first bonding point P1 to a predetermined value with high precision. There is a problem in that it is difficult to set a desired value with accuracy.

The purpose of this invention is to set the length of the wire connecting the lower end of the cut clamp and the first bonding point to a predetermined value with high precision by changing the cut clamp from the open state to the closed state while the cut clamp is stopped. Furthermore, by maintaining the closed state until the wire is positioned at the second bonding point, the length of the wire connecting the lower end of the cut clamp and the first bonding point is maintained reliably, and the length of the wire connecting the lower end of the cut clamp is maintained. By setting the length of the wire 3 connecting the lower end and the second bonding point to a predetermined value with high precision, the length of the loop connecting the first bonding point and the second bonding point can be increased. It is an object of the present invention to provide a wire bonding device that can be set to a desired value with precision.

(Means for solving the problems) The wire bonding apparatus of the present invention has the following means configuration to achieve the above object.

In other words, the wire bonding device of the present invention is
In a wire bonding device, a capillary; a bonding arm that holds the capillary; and a bonding arm that holds the capillary; and a bonding arm that holds the capillary; a cut clamp that begins to capture the wire and maintains the capture until the wire is positioned at a second bonding point; a clamp arm that captures the cut clamp; and relative positions of the bonding arm and the clamp arm. means for fixing the cut clamp; the clamp arm stops the movement of the cut clamp toward the second bonding point when the cut clamp reaches a predetermined height from the second bonding point; a stopper for maintaining a predetermined height from the second bonding point;
A wire bonding device characterized by comprising:

(Operation) The operation of the wire bonding apparatus of the present invention having the above-mentioned means will be explained below.

In the wire bonding device of the present invention, while the wire fixed to the first bonding point connects the first bonding point and the second bonding point, the cut clamp is moved from the second bonding point to a predetermined position. It has a stopper that stops it at the height. The cut clamp remains at this predetermined height, and only the capillary moves its tip closer to the second bonding point. The cut clamp is in an open state before it is stopped at the predetermined height, and after it is stopped at the predetermined height, the length of the wire connecting the lower end of the cut clamp and the first bonding point is determined in advance. The wire is held at the timing when it reaches a predetermined length. This state is maintained until the wire is positioned at the second bonding point, so when the wire is positioned at the second bonding point, the lower end of the cut clamp and the first
The length of the wire connected to the bonding point is the same as when the cut clamp holds the wire. The length of the wire connecting the second bonding point and the lower end of the cut clamp is kept constant by stopping the cut clamp at a predetermined height from the second bonding point. Therefore, the length of the loop connecting the second bonding point and the first bonding point is fixed. That is, the distance between the lower end of the cut clamp and the first bonding point is equal to the distance between the second bonding point and the lower end of the cut clamp when the wire is positioned at the second bonding point, plus the desired loop length. The cut clamp is closed to hold the wire at the timing when the lengths of the wires connecting it to the bonding point are equal, and the held state is maintained until the wire is positioned at the second bonding point. , the wire bonding device of the present invention is the first
The length of the loop connecting the bonding point and the second bonding point can be reliably set to the desired length.

As explained above, the wire bonding device of the present invention changes the length of the wire connecting the lower end of the cut clamp and the first bonding point by changing the cut clamp from the open state to the closed state while the cut clamp is stopped. The length of the wire connecting the lower end of the cut clamp and the first bonding point is determined with high precision to a predetermined value and the closed state is maintained until the wire is positioned at the second bonding point. By ensuring that the length of the wire connecting the lower end of the cut clamp and the second bonding point is set to a predetermined value with high precision,
The length of the loop connecting the first bonding point and the second bonding point can be set to a desired value with high precision.

(Example) Hereinafter, an example of the wire bonding apparatus of the present invention will be described based on the drawings. Fig. 1 is a configuration diagram of an embodiment of the wire bonding apparatus of the present invention, Fig. 2
The figure is an explanatory diagram of the operation of the loop length determining means of the embodiment of the wire bonding apparatus of the present invention.

FIG. 1 shows that the wire 3 is connected to the second bonding point 1.
It shows the state where it is positioned at 0. The wire 3 passes through the cut clamp 1 and reaches a second bonding point 10 by a capillary 2, and a loop 5 is formed between the second bonding point 10 and a first bonding point (not shown). There is.

The capillary 2 is held by a bonding arm 12, and the cut clamp 1 is held by a clamp arm 11. The bonding arm 12, the swing arm 14, and the clamp arm 11 share a support shaft 15, and are each supported to freely rotate around the central axis of the support shaft 15.

While the loop 5 is formed between the first bonding point and the second bonding point 10, the bonding arm 12 and the swinging arm 14 are connected by a fixing means (not shown). A stopper 19 is provided on a stopper arm 19a that shares a support shaft 15 with the bonding arm 12.

The stopper 19 fixes the height of the cut clamp 1 from the second bonding point 10 by stopping the counterclockwise rotation of the clamp arm 11 about the central axis of the support shaft 15.

Therefore, the stopper arm 19a does not rotate around the central axis of the support shaft 15 except when the height is changed, and the position of the stopper 19 is fixed at one position. Before the clamp arm 11 hits the stopper 19, the spring 17, which is a tension spring, pulls the clamp arm 11 and the swing arm 14 together, and the contact 18a provided on the clamp arm 11 and the contact point 18a provided on the swing arm 14 are connected to each other. The relative positions of the clamp arm 11 and the swing arm 14 are fixed at the position where the contact points 18b are in close contact with each other.

As described above, since the swing arm 14 and the bonding arm 12 are integrally connected while the loop 5 is being formed, the clamp arm 11 does not come into contact with the stopper 19 while the loop 5 is being formed. In this case, the relative positions of the clamp arm 11 and the bonding arm 12 are fixed, and therefore the distance between the cut clamp 1 and the capillary 2 is also fixed. FIG. 1 shows a state in which the clamp arm 11 hits the stopper 19, and then the bonding arm 12 rotates counterclockwise around the central axis of the support shaft 15 to position the tip of the capillary 2 at the second bonding point 10. As shown, there is a gap between the contacts 18a and 18b.

In the embodiment of the wire bonding apparatus of the present invention having the above configuration, a, b,
The cut clamp 1 and the capillary 2 operate in the order of c and d to determine the loop length.

In other words, in a of FIG. 2, since the relative positions of the clamp arm 11 and the bonding arm 12 are fixed, the distance between the lower end of the cut clamp 1 and the capillary tip Pa is fixed. The distance D is fixed and the capillary 2 is approaching the second bonding point with the cut clamp 1 open. In b of the same figure, the height of the lower end of the cut clamp 1 from the second bonding point is the second
Lower end height of cut clamp from bonding point
Ds is reached and the clamp arm 11 moves to the stopper 19.
It's hitting me. At c in the figure, only the bonding arm 12 is rotated while the clamp arm 11 is restrained by the stopper 19, so that only the capillary 2 is approaching the second bonding point. Moreover, the length of the wire 3 connecting the fixed cut clamp lower end Ps of the cut clamp 1 and the first bonding point P1 is the desired loop length plus the cut clamp lower end height Ds from the second bonding point. is equal to the value
In this state, the cut clamp 1 changes from the open state to the closed state and holds the wire 3.

In d of the same figure, the tip of capillary 2 is the second
The wire 3 forms a loop 5 between the capillary tip Pd and the first bonding point P1. As mentioned above, the cut clamp 1 changes from the open state to the closed state in the stopped state as shown in FIG. is set to a predetermined value with high precision. Furthermore, as shown in FIG. 2D, the cut clamp 1 is fixed in the state shown in FIG. 2C until the tip of the capillary 2 is positioned at the second bonding point.

Therefore, in the state shown in d of FIG. 2, the length of the wire 3 connecting the lower end Ps of the fixed cut clamp and the first bonding point P1 is the same as the state shown in c of FIG. The same value is ensured, and the cut clamp height Ds from the second bonding point is also accurately determined.
As a result, the length of the loop 5 connecting the capillary tip Pd, that is, the second bonding point and the first bonding point P1, is determined to a desired value with high precision.

(Effect of the invention) As explained above, the wire bonding device of the invention connects the lower end of the cut clamp and the first bonding point by changing the cut clamp from the open state to the closed state with the cut clamp stopped. The length of the wire is set to a predetermined value with high precision, and the closed state is maintained until the wire is positioned at the second bonding point, thereby connecting the lower end of the cut clamp and the first bonding point. By ensuring the length of the wire and setting the length of the wire connecting the lower end of the cut clamp and the second bonding point to a predetermined value with high precision,
This has the advantage that the length of the loop connecting the first bonding point and the second bonding point can be set to a desired value with high precision.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the wire bonding device of the present invention, FIG. 2 is an explanatory diagram of the operation of the loop length determining means of the embodiment of the wire bonding device of the present invention, and FIG. 3 is a conventional wire bonding device. FIG. 3 is an explanatory diagram of the operation of the loop length determining means of FIG. 1...Cut clamp, 2...Capillary, 3
... wire, 5 ... loop, 10 ... second bonding point, 11 ... clamp arm, 12 ...
Bonding arm, 14... Swinging arm, 15
... Support shaft, 17 ... Spring, 18a, 18b ... Contact, 19 ... Stopper, 19a ... Stopper arm, D ... Fixed distance between the lower end of the cut clamp and the tip of the capillary, Ds ... From the second bonding point Lower end height of cut clamp, Pa, Pb, Pc, Pd
...capillary tip, P1...first bonding point, Ps...lower end of fixed cut clamp.

Claims (1)

[Scope of utility model registration request] In a wire bonding device, a capillary; a bonding arm that holds the capillary; and a bonding arm that holds the capillary; and a bonding arm that holds the capillary; a cut clamp that begins to capture the wire and maintains the capture until the wire is positioned at a second bonding point; a clamp arm that captures the cut clamp; and relative positions of the bonding arm and the clamp arm. means for fixing the cut clamp; the clamp arm stops the movement of the cut clamp toward the second bonding point when the cut clamp reaches a predetermined height from the second bonding point; a stopper for maintaining a predetermined height from the second bonding point;
A wire bonding device comprising: