JPH058679Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement in a wire bonding apparatus that allows smooth wire feeding even when deposits are formed on the tip of a bonding tool.

(Background of the Idea) In wire bonding, a capillary or wedge (both are collectively referred to as a bonding tool) guides the wire to a predetermined position and performs bonding at each of the first and second bonding points.

After finishing the first bond, the bonding tool
The wire is fed out from the tip and moved from the first bonding point to the second bonding point, forming a wire loop during this time. After completing the second bonding, if the bonding tool is a capillary, it will rise and feed out the wire of the length necessary to form a ball from its tip, or if it is a wedge, it will rise to a certain height and then attach a predetermined length of wire to the tip. Unfold the wire tail.

If the wire is not fed out smoothly from the tip of the bonding tool (hereinafter referred to as wire feed) as described above, a predetermined wire loop, a predetermined ball, or a predetermined wire tail may not be formed. This may result in defective products or interruptions in bonding operations due to broken wires. In order to prevent this, conventional wire bonding equipment uses materials such as ceramic or tungsten carbide for the bonding tool to allow the wire to slide smoothly over hard surfaces, or the shape of the tip of the bonding tool is rounded. This prevents the wire from getting caught at the tip.

In recent years, in order to reduce the cost of semiconductor products, the plating material for the part where the second bond of the lead is made has become cheaper and the plating thickness has been reduced. It is becoming necessary to increase the pressure and the power of the ultrasonic waves to prevent the wire from becoming loose.

(Problems to be Solved by the Invention) However, the conventional wire bonding apparatus described above has the following problems.

In other words, because the pressure of the second bond and the power of the ultrasonic wave have been made stronger than before, the material of the part of the lead where the second bond is made is more likely to adhere to the tip of the bonding tool. In some cases, the wires may get stuck in the holes through which the wires pass, or in severe cases, cause the holes to become clogged. However, conventional wire bonding equipment cannot prevent the deposits from entering the holes and clogging the holes, so the wire feed inevitably becomes uneven and, in extreme cases, the wire feed stops.

For this reason, a predetermined wire loop, a predetermined ball, or a predetermined wire tail cannot be stably formed, leading to problems such as the occurrence of defective products and the interruption of bonding operations.

The purpose of the present invention is to apply ultrasonic vibration to the bonding tool while wire feeding is being performed, and use this ultrasonic vibration to shake off deposits from the tip of the bonding tool, thereby reducing obstruction of the wire feed inside the hole. With this, even when bonding is performed in such a way that deposits may form on the tip of the bonding tool, the wire can be fed smoothly and a predetermined wire loop, ball, or wire tail can be stably formed. Therefore, it is an object of the present invention to provide a wire bonding apparatus that can reduce the occurrence of defective products and the interruption of bonding operations.

(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
a bonding tool that guides the wire to a predetermined position and performs bonding; a position detection means that detects the position of the bonding tool and outputs a position signal; while the bonding tool is on its way from the first bonding point to the second bonding point When the bonding tool receives a position signal indicating that the bonding tool is in a predetermined section, the bonding tool attaches a predetermined length of wire or an ultrasonic excitation control means that outputs an ultrasonic excitation command signal when receiving a position signal indicating that the bonding tool is in the range of the position to be paid out; The present invention is characterized by comprising: an ultrasonic excitation means for exciting ultrasonic waves; and;

(Function) Hereinafter, the function of the wire bonding apparatus of the present invention having the above means configuration will be explained.

The bonding tool directs the wire into position and bonds at each of the first and second bonding points. The position detection means detects the position of the bonding tool and outputs a position signal.

The ultrasonic vibration control means receives a position signal, and when the position signal indicates that the bonding tool is in a predetermined section on the way from the first bonding point to the second bonding point, and when the bonding tool moves from the second bonding point. When the position signal indicates that the position is between a predetermined position on the way to the next first bonding point and a position where a predetermined length of wire is fed out to the tip of the bonding tool, an ultrasonic excitation command signal is sent. Output. The ultrasonic excitation means receives an ultrasonic excitation command signal, and based on the ultrasonic excitation command signal, ultrasonic vibration is applied to the bonding tool. Ultrasonic vibration is applied to the wire feed to form a ball or wire tail. Therefore, even if deposits are formed on the tip of the bonding tool during the second bonding process, the deposits are shaken off by the ultrasonic vibrations of the bonding tool, reducing obstruction to the wire feed inside the hole. Ultrasonic vibration reduces the contact between the wire and the inner wall of the hole, thereby reducing friction between them.

As explained above, in the wire bonding apparatus of the present invention, the bonding tool is subjected to ultrasonic vibration while wire feeding is being performed, so that the ultrasonic vibration shakes off deposits from the tip of the bonding tool. By dropping the wire feed, there will be less interference with the wire feed inside the hole.
At the same time, the friction between the wire and the inner wall of the hole is reduced by this ultrasonic vibration, so even when bonding is performed where there is deposits on the tip of the bonding tool, the wire feed can be performed smoothly and the specified Since wire loops, predetermined balls, or predetermined wire tails can be stably formed, the occurrence of defective products and interruption of bonding operations are reduced.

(Example) Hereinafter, an example of the wire bonding apparatus of the present invention will be described based on the drawings.

FIG. 1 is a block diagram of an embodiment of the wire bonding apparatus of the present invention. In the figure, a capillary 1 guides a wire 10 to a predetermined position. wire 10
are bonded by the capillary 1 at the first bonding point and the second bonding point of the bonding object 8. The bonding arm 2 is rotatably supported by a support shaft 4a of a bonding arm support section 4, holds the capillary 1 at one end, and is moved up and down by the vertical drive section 3 at the other end.

The bonding arm support section 4 is moved parallel to the bonding surface by linear movement of the X table 5 supporting the bonding arm support section 4 from below and the Y table 6 supporting the X table 5 from below in predetermined directions. Two-dimensional movement within a plane has become possible. An ultrasonic vibrator 17 is attached to the bonding arm 2, and when the ultrasonic oscillator 16 excites the ultrasonic vibrator 17, the capillary 1 is ultrasonically excited via the bonding arm 2.

The position detection section 11 detects the position of the capillary 1 from each position of the X table 5 and the Y table 6 and the vertical slide position of the vertical drive section 3, and outputs a capillary position signal 12. The ultrasonic oscillator control unit 14 receives the position signal 12 and controls the capillary 1
The position signal 1 indicates that the position is in a predetermined section on the way from the first bonding point to the second bonding point.
2 indicates that the capillary 1 is between a predetermined position on the way from the second bonding point to the next first bonding point and a position where a predetermined length of wire is fed out to the tip of the bonding tool. An ultrasonic oscillation timing signal 15 is sent to an ultrasonic oscillator 16 to instruct ultrasonic oscillation when the signal 12 indicates. The ultrasonic oscillator 16 excites the ultrasonic transducer 17 based on the ultrasonic oscillation timing signal 15, so the capillary 1
is ultrasonically excited during the wire feed between the first bond and the second bond and during the wire feed for ball formation after the second bond. For this reason, the second
Even if deposits are formed on the tip of the capillary 1 during bonding, the deposits are shaken off by the ultrasonic vibrations of the capillary 1, which reduces the obstruction of the wire feed in the hole through which the wire 10 of the capillary 1 passes. The ultrasonic vibration of the wire 1 reduces the contact between the wire 10 and the inner wall of the hole, thereby reducing the friction between them.

In this example, a capillary 1 is attached to the bonding tool.
However, the same effects as in this embodiment can be obtained by using a wedge.

(Effects of the invention) As explained above, the wire bonding apparatus of the invention applies ultrasonic vibration to the bonding tool while wire feeding is being performed, so that the ultrasonic vibrations bond the deposits. By shaking it off from the tip of the tool, there will be less interference with the wire feed inside the hole, and at the same time, this ultrasonic vibration will reduce the friction between the wire and the inner wall of the hole, preventing deposits from forming on the tip of the bonding tool. Even when performing bonding, the wire feed can be performed smoothly, and a predetermined wire loop, a predetermined ball, or a predetermined wire tail can be stably formed, reducing the occurrence of defective products and interruptions in bonding operations. It has the advantage of being

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the wire bonding apparatus of the present invention. 1... Capillary, 2... Bonding arm, 3... Vertical drive section, 4... Bonding arm support section, 4a... Support shaft, 5... X table, 6
...Y table, 7...Wire clamp, 8...
Bonding object, 11...Position detection unit, 12
... Capillary position signal, 14 ... Ultrasonic oscillator control section, 15 ... Ultrasonic oscillation timing signal, 1
6... Ultrasonic oscillator, 17... Ultrasonic vibrator.

Claims (1)

[Scope of utility model registration request] a bonding tool that guides the wire to a predetermined position and performs bonding; a position detection means that detects the position of the bonding tool and outputs a position signal; while the bonding tool is on its way from the first bonding point to the second bonding point A wire of a predetermined length is attached to the tip of the bonding tool from a predetermined position on the way from the second bonding point to the next first bonding point. an ultrasonic excitation control means that outputs an ultrasonic excitation command signal when receiving a position signal indicating that the bonding tool is in the range of the position to be paid out; A wire bonding device characterized by comprising: an ultrasonic vibration excitation means for vibrating ultrasonic waves;