JPH033938B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wire bonding device for bonding between an IC element and a lead.

[Conventional technology]

In conventional bonding equipment, a bonding head that supports a bonding tool so as to be able to reciprocate in the vertical direction is installed on an XY table, and is placed on a base frame in the
It was held so that it could be moved in any direction. A camera was also placed on the XY table to detect the position and orientation of the IC and display the image on the ITV.

On the other hand, the IC carrier such as the ceramic package or lead frame that supports the IC is transferred by another transfer mechanism (this transfer direction is the X direction), and the IC is placed at the reference origin directly under the bonding tool.
It is held by a holding mechanism so that the center is located. This holding mechanism is supported on a rotary table so as to rotate around the Z axis in the Z direction perpendicular to the IC element surface.

During the bonding operation, the IC carrier transferred by the transfer mechanism is held by the holding mechanism so that the center of the IC carrier substantially coincides with the reference origin. However, due to errors in mounting the IC onto the carrier using a die bonder or the like in the previous process, the center of the IC does not exactly match the center of the carrier, and
If the IC is correctly oriented in the X direction (or in the Y direction perpendicular to it)
direction).

ΔX of the deviation in the X direction, ΔY of the deviation in the Y direction,
and the deviation Δθ in the center direction is detected by a camera,
Using these values, the actual coordinates are calculated based on the pre-stored coordinates of the IC pad and the coordinates of the end of the lead, and the XY table and rotary table are driven based on the corrected coordinates to drive the pad. This is done by repeatedly moving a bonding tool back and forth between the bonding tool and the lead.

[Problem to be solved by the invention]

Conventionally, this reciprocating movement of the bonding tool was driven by the movement of an XY table provided in the bonding head, and such conventional tools had the following runner-up points.

(1) The bonding head, camera, ITV, wire reel, etc. are placed on the XY table on the bonding head side and are relatively heavy, which puts a load on the XY table and impairs its operational speed.

(2) Since the center of rotation of the rotation mechanism of the holding mechanism and the center of the XY table of the bonding head are far apart, the positional accuracy of bonding decreases due to the influence of thermal expansion between them.

(3) The bonding tool is attached to the tip of the elongated bonding arm, and
The vibration in this direction generates three-dimensional vibration, resulting in poor bonding positioning and poor bonding.

(4) The camera is subject to vibrations in the X and Y directions, which causes errors in detecting the position and direction of the IC due to pattern recognition, etc., and also causes blur in ITV images, making observations inaccurate.

There are drawbacks such as.

The present invention eliminates these conventional drawbacks, reduces the load on the XY table, increases responsiveness, prevents errors caused by thermal expansion, and minimizes vibrations to the bonding tool and camera to prevent malfunctions and detection errors. It is an object of the present invention to provide a bonding device that can prevent the above.

[Means to solve the problem]

The present invention includes a holding mechanism that supports a bonding tool on a bonding head so as to be reciprocatable along the Z direction perpendicular to the IC element surface, and that holds an IC carrier carrying an IC to be bonded.
It is supported so as to be rotatable around the Z axis in the Z direction and movable in the X and Y directions that are perpendicular to the Z direction and also perpendicular to each other, and is installed opposite to the holding mechanism. A slide rail that slides back and forth is continuously connected to each guide path, and claws are provided at equal intervals on the slide rail and the feed arm of the IC carrier that moves on the holding mechanism.
A transfer mechanism is provided that allows the feed arm to be moved up and down in the X direction, Y direction, and up and down synchronously with respect to the IC carrier, and the bonding tool is moved back and forth only approximately in the Z direction, and the bonding tool and Relative movement with the IC in the X and Y directions and relative rotational movement around the Z axis is performed only by movement of the holding mechanism, thereby bonding between the IC element and the lead. This is a wire bonding device.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

In FIGS. 1 and 2, reference numeral 1 denotes a base frame, and a bonding head 3 is fixed via a frame 2. In FIG. A capillary 5 as a bonding tool is supported on the bonding head 3 via a bonding arm 4 so as to be able to reciprocate up and down in the Z direction of a Z axis 6 (perpendicular in this embodiment) perpendicular to the IC element surface. . camera 7,
A lighting lamp 8 and an ITV 9 are also fixed to the bonding head 3.

Reference numeral 10 denotes an X table, which reciprocates in the X-axis 11 direction. Reference numeral 12 denotes a Y table, which reciprocates in the direction of the Y axis 13 relative to the X table 10. 14 is a rotary table, Y table 1
2, it performs reciprocating rotational movement relative to the axis in the Z direction, and rotates around the Z axis 6 when the X table 10 and the Y table 12 are in the neutral position.

Above the rotation center axis of the rotary table 14,
A holding mechanism 16 is provided for placing and holding IC carriers 15A, 15B, 15C, etc. carrying ICs to be bonded. In this embodiment, an example of a semi-finished product of a DIP type IC package is shown as the carrier 15A.

The outline of the transfer mechanism such as this carrier 15A is shown in the first section.
To explain with reference to the figure and FIG. 3, 17 is the carrier 1
5D etc. to the holding mechanism 16, a guide path 18;
is a guide path that guides the carrier 15A and the like to the next process. 19 and 20 guide the carrier 15A and the like through the guide path 1.
It is a feed arm that moves over 7 and 18,
Details will be described later.

The X-axis 11 is the center line of the moving path of the carrier 15A, etc., and the Y-axis 13 is a straight line that is perpendicular to the X-axis 11 and passes directly under the capillary 5. The center of the IC is the reference origin that should be located when the IC is mounted on the body 15A with accuracy in both position and direction.

FIG. 4 shows details of the carrier 15C. Carrier 1
The IC 22 is installed in the center of the IC 22, and multiple leads 23 are installed on both sides of the IC 22 in advance. Bonding is performed by passing a wire 24 between the lead 23 and the lead 23.

Details of the transfer mechanism such as the carrier 15A are shown in 5th to 8th.
This will be explained using figures. In these figures, the carriers 15B and 15D should be represented by solid lines, but they are shown by two-dot chain lines to avoid cluttering the figures.

In FIGS. 5 and 6, the carrier 15C is the holding mechanism 1.
6, the center of the carrier 15C coincides with the reference origin 21.
25 and 26 are held by slide rails in the guide paths 17 and 18 so that they can slide in the X direction, and when the carrier 15A etc. moves, they protrude and abut against the holding mechanism 16 as shown in FIGS. 5 and 6. Carrier 15
Continuously connect transfer paths such as A.

The feed arms 19 and 20 have two tabs at equal intervals.
7, 28, 29 are provided, and the claws 27,
28 and 29 are moved synchronously in the X and Y directions. The movement is, for example, claw 2
8, as shown in FIG. 5, performs a movement that draws a rectangular locus such as ABCD, and draws the carrier 15C that was on the guide path 17 and places it on the holding mechanism 16. By moving the feed arms 19, 20 synchronously in this manner, the guide paths 17, 18,
The carriers 15A and the like on the holding mechanism 16 are intermittently transferred while maintaining equal intervals.

After the carrier 15C to be bonded is placed in a fixed position on the holding mechanism 16, the slide rails 25 and 26 are retracted and separated from the holding mechanism 16 as shown in FIGS. is raised, and then the camera 7 detects the positional deviations ΔX and ΔY in the X and Y directions and the deviation Δθ in the center direction of the IC 22 using detection means such as pattern recognition, and the detected values are stored in advance. I C
The actual coordinates are calculated based on the coordinates of the pad and lead end of No. 22, and the X table 1 is calculated accordingly.
The 0, Y table 12 and rotary table 14 are operated to perform bonding between the pad of the IC 22 and the end of the lead.

In that case, as shown in FIG.
are displaced as ΔX, ΔY, and Δθ, but since the slide rails 25 and 26 are retracted, they do not deviate.

When the bonding of one carrier 15C is completed, the holding mechanism 16 is returned to the neutral state shown in FIG. , claw 28 etc. from B to C
→D→A, the next carrier 15D is placed on the holding mechanism 16, and bonding is performed.

In the above embodiment, the X table 10, the Y table 12, and the rotary table 14 are placed in this order from bottom to top, but the order is not limited to this and may be any other order. The rotation center axis of the rotary table 14 does not necessarily have to pass through the reference origin 21, but may be an axis in the Z direction that passes through the optical axis of the camera 7 or another point.

In the above embodiments, the following excellent effects can be achieved.

(1) Relatively heavy objects such as the bonding head 3, camera 7, lighting lamp 8, and ITV 9 are fixed,
Since only a minimum weight is applied to the X table 10, Y table 12, and rotary table 14, the movement of each table becomes extremely fast, and the working speed and accuracy are improved.

(2) Since the rotation center axis of the rotary table 14 and the center of the XY table can be aligned with each other or positioned close to each other, errors caused by thermal expansion can be prevented.

(3) Since the bonding arm 4 is not subjected to vibrations in the X, Y and rotational directions, and only receives minimal vibrations in the Z direction, poor bonding positioning and poor bonding can be prevented.

(4) Since camera 7 receives almost no vibration, IC2
2. Reduce the detection error of position and direction deviation,
This prevents blurring of the ITV9 image, making accurate and easy observation, and prolonging the lifespan of the camera 7 and ITV9 because they are not subject to vibration.

The effect is as follows.

In addition to the above-mentioned ceramic package, the carrier 15A can also be applied to a lead frame.

〔Effect of the invention〕

The present invention provides a holding mechanism for holding an IC carrier.
It is supported so as to be rotatable around the Z axis in the Z direction and movable in the X and Y directions that are perpendicular to the Z direction and also perpendicular to each other, and is installed opposite to the holding mechanism. A slide rail that slides back and forth is continuously connected to each guide path, and claws are provided at equal intervals on the slide rail and the feed arm of the IC carrier that moves on the holding mechanism.
A transfer mechanism is provided that allows the feed arm to be moved up and down in the X direction, Y direction, and up and down synchronously with respect to the IC carrier, and the bonding tool is moved back and forth only approximately in the Z direction, and the bonding tool and Relative movement with the IC in the X and Y directions and relative rotational movement around the Z axis is performed only by movement of the holding mechanism;
The related operations between the IC carrier and the bonding tool can be performed safely and with high precision, greatly increasing reliability, reducing processing time, and minimizing the load on the XY table.
Improved speed response and accuracy, unaffected by temperature, minimizes vibration to the bonding tool, improves reliability of the bonding tool, eliminates vibration to the camera, and improves the position and orientation of the IC. It is possible to improve the accuracy of misalignment detection and extend the life of cameras and ITVs, which is extremely effective in practical terms.

[Brief explanation of the drawing]

The drawings relate to an embodiment of the present invention; FIG. 1 is a front view, FIG. 2 is a side view thereof, FIG. 3 is a plan view taken from the - line in FIG. 1, and FIG. 4 is a longitudinal cross-section of the carrier. 5 and 6 are a front view and a plan view of the vicinity of the holding mechanism, and FIGS. 7 and 8 are a front view and a plan view of the same portion when the position and direction are corrected. 1...Base frame, 2...Frame, 3...
...Bonding head, 4...Bonding arm, 5...Capillary, 6...Z-axis, 7...Camera, 8...Lighting light, 9...ITV, 10...X table, 11...Z-axis, 12 ...Y table, 1
3...Y axis, 14...Rotary table, 15A, 1
5B, 15C, 15D, 15E, 15F... carrier, 16... holding mechanism, 17, 18... guide path,
19, 20...Feed arm, 21...Reference origin,
22...IC, 23...lead, 24...wire,
25, 26...Slide rail, 27, 28, 2
9...Tlaw.

Claims (1)

[Claims] 1. A bonding tool is supported on the bonding head so that it can reciprocate along the Z direction perpendicular to the IC element surface, and a holding mechanism that holds the IC carrier that supports the IC to be bonded is supported in the Z direction in the Z direction. supported so as to be able to rotate around an axis and to be movable in the X and Y directions that are perpendicular to the Z direction and also perpendicular to each other;
A slide rail that slides back and forth is continuously connected to a guide path provided opposite to the holding mechanism, and an IC that moves on the slide rail and the holding mechanism.
The feed arm of the carrier is provided with claws at equal intervals, and the feed arm is synchronously
The bonding tool is provided with a transfer mechanism that can be moved up and down in the X direction, the Y direction, and up and down, and the bonding tool is reciprocated almost only along the Z direction, and the bonding tool and the IC are moved relative to each other in the X direction and the Y direction, as well as in the Z axis. 1. A wire bonding apparatus characterized in that the relative rotational movement of the surroundings is performed only by movement of the holding mechanism to bond an IC element and a lead.