JPH0427167Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention particularly relates to a wire bonding device in which a device for vertically moving a capillary through which a wire is inserted is improved.

(Prior Art) As a capillary vertical movement device in a conventional wire bonding device, there is a device as shown in FIG.

That is, a motor 33 is fixed to a block 32 erected on an XY table 31, and a ball screw shaft 35 is supported by bearings 36 and 37 parallel to the axis of a motor rotation shaft 34.

A toothed pulley 38 is fixed to the motor rotating shaft 34, a toothed pulley 39 is fixed to the ball screw shaft 35, and a timing belt 40 is stretched between these pulleys 38 and 39.

A bearing 43 is rotatably attached to a protrusion 42 fixed to a nut member 41 that is screwed onto the ball screw shaft 35 via a ball.

On the one hand, a bonding arm with a capillary 44 through which a wire W is inserted is attached to the tip, and in this example, a horn 45 with an ultrasonic vibrator at the other end is attached to the holder 4.
6, and the holder 46 is held on the XY table 31
A shaft 48 is swingably supported by a block 47 fixed to the shaft. The bearing 43 is placed between the opposing surfaces of two guide plates 49 and 50 fixed to the holder 46.
are mated.

51 is already a lead frame 52 in the previous process.
It is a semiconductor chip bonded on top.

To explain the operation, when the lead frame 52 is sent and stopped at a fixed position, the position of the bonding point is recognized by a pattern recognition device (not shown), and the XY table 31 is moved by a correction amount based on this position recognition. , the tip of the capillary 44 is located directly above the bonding point. Then, a predetermined pulse signal is applied to the motor 33, and the motor rotation shaft 34
rotates by a predetermined angle in response to the pulse.

The rotation of the motor rotation shaft, that is, the rotation of the pulley 38 is controlled by the pulley 39 and the ball screw shaft 3 via the belt 40.
5 and raises the nut member 41 by a predetermined amount.

As the nut member 41 rises, the bearing 43 also rises, which pushes up the guide plate 49, so that the holder 46 and the horn 45 fixed thereto swing clockwise about the shaft 48.
Therefore, the capillary 44 attached to the tip of the horn 45 is processed and bonded to the first bond point on the semiconductor chip 51.

(Problem to be solved by the invention) However, in the above device,
Since the motor rotation shaft 34 and the ball screw shaft 35 are connected by a timing belt 40, tracking performance becomes poor during high-speed rotation, and the belt tends to wear out due to friction between the belt and the pulley. Since the axis of the ball screw shaft 31 and the axis of the ball screw shaft 35 are vertical, the center of gravity becomes higher and as the speed of the XY table 31 increases, undesirable vibrations occur when the XY table starts or stops at high speed. is transmitted through the horn 45 to the capillary 4
4, there was a problem in that it adversely affected the bonding results performed using the capillary.

(Means for solving the problems) The present invention has been made to solve the above problems. That is, the wire bonding device according to the present invention fixes a motor on a table so that its rotating shaft axis is horizontal, aligns and integrally connects a male threaded shaft with the motor rotating shaft, and supports this with a bearing. A nut member is non-rotatably screwed onto the male threaded shaft, while a bonding arm with a capillary attached to the tip is held by a holder, the holder is swingably supported on the table, and the nut member is and the holder are connected via a connecting rod so that horizontal movement of the nut member can be converted into a swinging motion of the holder.

(Function) When a predetermined pulse signal is applied to the motor, the motor rotates by a predetermined angle, which causes the nut member to move forward in the horizontal direction, and the horn and the capillary attached to it to move around the fixed shaft via the connecting rod. The capillary swings downward, and the wire protruding from the tip of the capillary is pressed against the bonding point to perform bonding.

(Example) The present invention will be explained below with reference to the drawings.

Figure 1 is a plan view showing one embodiment of the present invention;
The figure is a side view of FIG. 1.

Block 2 installed on XY table 1 has
The motor 3 is fixed, and the motor rotation shaft 4
A male threaded shaft, in this example a ball screw shaft 5, is supported by bearings 6 and 7 so as to be aligned with each other. The motor rotation shaft 4 and the ball screw shaft 5 are integrally connected by a coupling 8. A nut member 9 is non-rotatably screwed onto the ball screw shaft 5 by a rotation preventing means (not shown).

On the other hand, a holder 12 is swingably supported on a shaft 13 on a block 11 fixed on the XY table 1.
A bonding arm with an ultrasonic transducer 14 attached to the holder 12. In this example, a horn 15 is fixed to the holder 12, and a capillary 16 through which a wire W paid out from a wire spool (not shown) is inserted is fixed to the tip of the horn 15. has been done.

The protrusion 17 provided on the nut member 9 and the holder 1
2 are connected to each other by bearings 19 and 20 via a connecting rod 18 so that horizontal movement of the nut member 9 can be converted into a rocking motion of the holder 12.

Note that 21 is a lead frame, and 22 is a semiconductor chip that has already been die-bonded on the lead frame.

To explain the operation, when the lead frame 21 is sent and stopped at a predetermined position, pattern recognition similar to that described in the conventional example is performed, and the XY table 1 is operated to bring the tip of the capillary 16 to the first bond point. come directly above. Then, a pulse signal is applied to the motor 3, the motor rotation shaft 4 rotates by a predetermined angle, and the nut member 9 moves forward (rightward in the figure).
Then, the holder 12 and the horn 15 fixed thereto are swung clockwise via the connecting rod 18. Then, the capillary 16 fixed to the tip of the horn 15 is lowered and wire-bonded to the first bond point on the semiconductor chip 22. During bonding, ultrasonic vibration energy is applied to the capillary 16 through the horn 15 by the operation of the ultrasonic vibrator 14, as in the conventional method.

After the first bond is completed, a predetermined pulse is applied to the motor, and the motor rotating shaft rotates in the opposite direction by a predetermined angle, causing the nut member 9 to move back by a predetermined amount (to the left in the figure).
By swinging the holder 12 and the horn 15 fixed thereto by a predetermined angle counterclockwise via the connecting rod 18, the capillary 16 is raised by a predetermined amount, and the XY table 1 is operated to raise the capillary 16. is carried to just above the second bond point on the lead frame 21, and the capillary 16 is connected by applying a predetermined pulse to the motor 3 again.
Lower it and perform the second bond.

After the second bonding is completed, the motor is reversed again to raise the capillary 16, and in the middle of this, a wire clamper (not shown) is closed, and the wire W is cut just above the second bonding point in preparation for the next first bonding.

By repeating the above operations, bonding processing is performed sequentially.

As the motor, in addition to a DC servo motor, an AC servo motor or a pulse motor can be used.

(Effects of the invention) As described above, the wire bonding device according to the invention fixes the motor on a table so that the axis of its rotating shaft is horizontal, aligns the male threaded shaft with the motor rotating shaft, and integrates the motor. A nut member is non-rotatably screwed onto the male threaded shaft, while a bonding arm with a capillary attached to the tip is held by a holder, and the holder is rocked on the table. The nut member and the holder are connected to each other via a connecting rod so that the horizontal movement of the nut member can be converted into a rocking motion of the holder. The center of gravity of the entire capillary vertical movement device installed on the table is significantly lower than that of conventional devices, which reduces vibrations caused by high-speed starting and stopping of the XY table, as well as Since the structure of the motion direction device including the connecting rod and holder is simple, the holder and bonding arm can follow the rotation of the motor well, and from the above, even during high-speed operation, reliable and good bonding can be performed. It has the effect of being able to

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the present invention, FIG. 2 is a side view of FIG. 1, and FIG. 3 is a side view of a conventional example. 1...XY table (table), 3...Motor, 4...Motor rotating shaft, 5...Ball screw shaft (male screw shaft), 6...Bearing, 7...Bearing, 9...Nut member, 12... ...Holder, 13...Axis, 15...
...Horn (bonding arm), 16...Capillary, 18...Connecting rod.

Claims (1)

[Scope of utility model registration request] The motor is fixed on a table so that the axis of its rotating shaft is horizontal, the male threaded shaft is aligned and integrally connected to the motor rotating shaft, and this is supported by a bearing, and a nut member is attached to the male threaded shaft so that it cannot rotate. At the same time, a bonding arm with a capillary attached to its tip is held by a holder, and the holder is pivotably supported on the table, and the nut member and the holder are connected via a connecting rod. . A wire bonding apparatus, characterized in that the nut member is connected so that horizontal movement of the holder can be converted into a swinging motion of the holder.