JPS6227741B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic wire bonding apparatus for bonding a wire to a sample using ultrasonic vibration.

Conventionally, in ultrasonic wire bonding equipment using wedges, the shape of the wedge limits the direction in which the wire can be inserted, and the wire is inserted into the wedge at an inclined angle (for example, at an angle of 30°, 45°, 60°, etc.). . However, in recent years, as the samples to be bonded have become more complex and the number of wires to be connected has increased, some wires have interfered with the outer frame of the sample during bonding.

For this reason, methods have been proposed that use a capillary to hold the wire vertically to form a tail at the tip, or to form a ball in the wire to drive the capillary in the X and Y directions and guide it to the bonding point. It's here. However, as is well known in ultrasonic wire bonding, it is desirable to perform wire bonding with the ultrasonic vibration direction and wire connection direction in the same direction, and simply connect the capillary.
The method of bonding by driving in the XY directions has the drawback that the bonding state of the wire varies depending on the angle with respect to the ultrasonic vibration direction, and stable bonding cannot be performed.

The present invention was made in view of the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide an ultrasonic wire bonding apparatus that can always perform stable wire bonding using a capillary.

Hereinafter, the present invention will be explained with reference to illustrated embodiments.

The drawings show an embodiment of the present invention, in which FIG. 1 is a side sectional view, FIG. 2 is a front view, and FIG. 3 is a partially sectional plan view. A horn 2 having a capillary 1 at its tip is held in a holder 3. A shaft 3a is formed on both sides of the holder 3, and this shaft 3a is connected to both sides 4a of an inverted U shape formed on the rotating block 4.
It is rotatably supported by a bearing 5 provided in the. A clamper 6 is fixed to the lower surface of the rotating block 4 so as to be located above the capillary 1. Further, a contact arm 7 is vertically fixed to the shaft 3a, and a contact rod 8 is fixed to the rotating block 4 via an insulating block 9 in correspondence with the contact arm 7. A spring 10 is attached to the contact arm 7 so that the contact arm 7 is always in contact with the contact rod 8.
One end of the spring 10 is hung, and the other end of the spring 10 is attached to a spring hook 1 screwed onto the rotating block 4.
It is multiplied by 1. The spring 10 moves to apply pressure (hereinafter referred to as bonding load) to a sample (not shown), and the bonding load is adjusted by a spring hook 11.
After adjustment, lock with nut 12.

A shaft 4c is formed in the upper part of the rotating block 4 in a portion corresponding to the capillary 1 through which a hole 4b passes. The shaft 4c is rotatably supported by a slide block 20 via a bearing 21, and is positioned in the vertical direction by a collar 4d of the shaft 4c and a nut 22. A plurality of energizing contact plates 24 are fixed to the lower end side of the shaft 4c via cylindrical insulating members 23. Then, the brush 25 is moved to the slide block 20 so as to be in close contact with the energizing contact plate 24.
It is fixed to an insulating angle 26 attached to. Also, a pulley 27 fixed to the upper end side of the shaft 4c
A belt 30 is hung between the pulley 29 fixed to the output shaft of a motor 28 fixed to the upper part of the slide block 20.

Therefore, when the motor 28 rotates, the pulley 2
9, the rotating block 4 rotates around the shaft 4c via the belt 30 and pulley 27. As a result, the horn 2 rotates around the shaft 4c, that is, the capillary 1 disposed coaxially with the shaft 4c.

A rotatable spool 31 is detachably attached to the upper part of the pulley 27. Further, a wire presser 33 is attached to the upper part of the pulley 27 for applying appropriate tension to the wire 32 fed out from the spool 31. When the wire 32 is paid out from the spool 31, tension is applied to it by holding it between the wire holders 33 and the shaft 4
It passes through the capillary 1 through the hole 4b of c, the clamper 6, and is delivered to the lower part of the capillary 1.

Further, V rails 40 are fixed to both sides of the slide block 20 in the vertical direction, and balls or rollers 4
It is sandwiched between V-rails 43 which are fixed to a fixed block 42 via 1 and can be slid up and down. An arm 44 is located inside the fixed block 42.
A support shaft 45 to which the arm 44 is fixed is rotatably supported by bearings 46 attached to both sides of the fixed block 42. A cam follower 47 rotatably attached to one end of the arm 44 contacts the bottom surface of the slide block 20, and a cam follower 48 rotatably attached to the other end of the arm 44 contacts the bottom of the fixed block 4.
It is in contact with a cam 50 fixed to the output shaft of a motor 49 attached to the side surface of the motor 2. Also arm 4
A spring 53 is applied to a spring hook 51 fixed to the cam follower 48 and a spring hook 52 fixed to the fixed block 42.
is biased so as to come into pressure contact with the cam 50. Furthermore, the fixed block 42 is mounted on an XY table 54 that is driven in the XY directions by means not shown.

Therefore, when the motor 49 rotates, the arm 44 swings about the support shaft 45 along the upward and downward curve of the cam 50, and the slide block 20 moves up and down. As a result, the capillary 1 moves up and down together with the rotating block 4.

Although not shown, encoders are attached to the rear portions of the motors 28 and 49 to convert the origin and rotation angle of the motors into electrical signals.

Next, the operation of this device having such a configuration will be explained. First, when the position of the sample is detected by a camera (not shown) and the bonding position data is corrected, the XY table 54 is
is driven to move the entire illustrated device in the XY directions to position the capillary 1 directly above the first bond point. Also, based on the data, the motor 28 rotates simultaneously with the driving of the XY table 54. motor 28
When the rotary block 4 rotates, the rotating block 4 rotates via the belt 30, and the holder 3 rotates around the shaft 4c. Therefore, the horn 2 rotates around the capillary 1 and is thereby positioned in the direction connecting the first bond point and the second bond point where the wire 32 is connected.

Next, the motor 49 is driven, and the arm 44 rotates in the direction of arrow A about the support shaft 45 due to the downward curve of the cam 50, and the slide block 20 is lowered by its own weight. As a result, the capillary 1 also descends, and when the capillary 1 touches the first bond point, the descending of the capillary 1 is stopped, but since the slide block 20 is in the descending motion, the holder 3 is moved around the axis 3a as indicated by the arrow direction, and the contact arm 7 separates from the contact rod 8. When the contact arm 7 separates from the contact rod 8 in this way (hereinafter referred to as level detection), this is detected electrically and the motor 4
Stop 9. Next, the clamper 6 holding the wire 32 is opened, and then ultrasonic oscillation is performed, and bonding is performed by the capillary 1 at the first bonding point.

After the bonding of the first bond point is completed, the motor 4
9 rotates in the opposite direction, the arm 44 rotates in the opposite direction to arrow A along the upward curve of the cam 50, and together with the slide block 20, the capillary 1 is raised and stopped. Next, the XY table 54 is driven to move the capillary 1 directly above the second bond point. Subsequently, the motor 49 is driven and the capillary 1 is lowered as in the case of the first bond point. When capillary 1 is grounded to the second bond point, motor 4 is
9 stops, ultrasonic oscillation is performed, and bonding is performed by the capillary 1 to the second bond point.

After completing the bonding of the second bond point, the motor 4
9 rotates in the opposite direction to raise the capillary 1. At this time, the clamper 6 is closed at an appropriate timing to cut the wire 32. Then, the capillary 1 rises and the motor 49 stops, thereby completing the connection of the first wire.

Next, move on to connecting the second wire. That is, XY
The table 54 is driven to position the capillary 1 directly above the first bond point where the second wire is connected, and the motor 28 is rotated to position the horn 2 in the wire connection direction. Next, as in the first wire connection, the capillary 1 is lowered to perform bonding. By sequentially repeating these operations, bonding of one sample is completed.

As is clear from the above explanation, according to the ultrasonic wire bonding apparatus of the present invention, the horn is configured to rotate around the capillary, so even if the capillary holding the wire vertically is used, The ultrasonic vibration direction and the wire connection direction can be made to be in the same direction, and stable bonding can be performed.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which FIG. 1 is a side sectional view, FIG. 2 is a front view, and FIG. 3 is a partially sectional plan view. 1... Capillary, 2... Horn, 3... Holder, 4... Rotating block, 20... Slide block, 28... Motor, 30... Belt, 31
... Spool, 32 ... Wire, 42 ... Fixed block, 44 ... Arm, 49 ... Motor, 50
……cam.

Claims (1)

[Claims] 1. A capillary that holds the wire vertically, a horn that holds this capillary at one end and emits ultrasonic waves, and a hole that holds this horn so that it can move up and down and allows the wire that is inserted vertically into the capillary to pass through. a rotating block for rotating the horn around an axis formed coaxially with the capillary, and a clamper for clamping the wire that is attached to the rotating block and extends perpendicularly above the capillary. , a slide block that rotatably holds the rotary block around the axis of the wire inserted into the capillary, a fixed block that holds the slide block so as to be movable up and down, and a fixed block that is moved in the X and Y directions. An ultrasonic wire bonding apparatus comprising an XY table, a rotation drive mechanism for rotating the rotary block, and a vertical drive mechanism for moving the slide block up and down.