JP2977017B2 - Bonding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a bonding apparatus for bonding an electronic component to a substrate.

[0002]

2. Description of the Related Art Conventionally, there has been known a bonding apparatus provided with a bonding tool which can be moved up and down and a load cell which detects a load when an electronic component is pressed by the bonding tool. In such a conventional apparatus, the load cell is disposed above the bonding tool, and the load cell is brought into contact with the bonding tool. Then, the elevating member to which the bonding tool and the load cell are attached is lowered, and the electronic component is pressed by the bonding tool to be bonded to the substrate. At this time, the pressing load by the bonding tool is detected by a load cell provided in contact with a position above the bonding tool.

[0003]

In the above-described conventional apparatus, for example, when the pressing amount of the bonding tool is increased by mistake in setting the lowering amount of the bonding tool, the electronic components and the substrate are damaged. In addition, there is a disadvantage that the load cell is also damaged.
Further, when the load cell breaks down, the pressing load by the bonding tool cannot be detected. In this case, too, the pressing load by the bonding tool increases more than necessary, and there is a disadvantage that the electronic component and the substrate are damaged. .

[0004]

[Means for Solving the Problems] In view of such circumstances,
The present invention relates to a bonding apparatus including a bonding tool provided to be able to move up and down, and a load cell for detecting a load when an electronic component is pressed by the bonding tool, wherein a predetermined load is previously applied to the load cell via the bonding tool. In addition, when the electronic component is pressed by the bonding tool, the load detected by the load cell is reduced.

[0005]

According to such a configuration, even if the lowering amount of the bonding tool is increased more than necessary for some reason, the load cell is not subjected to a load larger than the predetermined load applied in advance, so that the load cell may be damaged. In addition, since the load applied to the substrate and the electronic component does not become larger than the value obtained by adding the load previously applied to the load cell and the weight of the bonding tool, the substrate and the electronic component are not damaged by an excessive pressing load. Furthermore, even if the load cell breaks down, the sensor detects that the bonding tool has separated from the load cell and stops the pressing operation, so that an excessive load is not applied to the board and electronic components as described above, preventing damage. it can.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. In FIGS. 1 and 2, reference numeral 1 denotes a bonding apparatus for bonding a chip 3 to a substrate 2. The bonding apparatus 1 includes a positioning stage 4 on which the substrate 2 is placed and which can be moved in XY directions perpendicular to each other on a horizontal plane.
A known bonding tool 5 for pressing and bonding the chip 3 from above is provided thereon. An elevating member 6 is provided on a frame (not shown) so as to be able to move up and down.
The bonding tool 5 is arranged to be able to move up and down. The elevating member 6 is moved up and down by a screw shaft 7 and a motor 8. The operation of the motor 8 is controlled by a control device (not shown). Then, the control device rotates the motor 8 to lower the bonding tool 5 from the position of the rising end in the figure by a predetermined amount of descent. A conventionally known load cell 11 is attached to the vertically moving member 6 so as to face vertically upward.
Further, the air cylinder 1 is opposed to the load cell 11.
2 is attached to the elevating member 6 vertically downward. In this embodiment, one side of the bonding tool 5 has an engaging portion 5a.
The engagement portion 5a is connected to the load cell 11
, And the entire bonding tool 5 is supported by the load cell 11 so as to be able to move up and down relatively with respect to the elevating member 6. In this state, the air cylinder 12 is pressed down by contacting the engaging portion 5a of the bonding tool 5 from above from above, whereby a predetermined load (for example, 40 kg) is applied to the load cell 11 in advance. . Therefore, in the state before the start of the bonding operation, assuming that the load of the bonding tool 5 is, for example, 10 kg, a total load of 50 kg of the 10 kg and the load of 40 kg applied by the air cylinder 12 is added to the load cell 11 in advance. The load cell 11 detects the load of 50 kg and inputs it to the control device. In this embodiment, when the bonding tool 5 is lowered and the chip 3 is pressed against the substrate 2, the engaging portion 5 a is moved with the lowering of the bonding tool 5.
As a result, the detected load of the load cell 11 is reduced relative to the lifting member 6. In this embodiment, the controller stops the operation of the motor 8 and stops the lowering of the bonding tool 5 when the detected load of the load cell 11 gradually decreases from the above 50 kg to reach 20 kg. ing. Further, the bonding tool 5 of the present embodiment has a dog 5b protruding from the opposite side of the engaging portion 5a, and a sensor 12 is provided at a predetermined position of the lifting member 6 above the dog 5b.
Is provided. This regulates the position of the rising end when the bonding tool 5 is raised relative to the lifting member 6. That is, in the state before the start of the operation and during the normal bonding operation, the dog 5b
However, if the bonding tool 5 is relatively raised during the bonding operation beyond the set stroke for abnormality detection, the dog 5b is detected by the sensor 13. In this case, the sensor 13 inputs the detection of the dog 5b to the control device, and in this case, the control device
The operation of the motor 8 is forcibly stopped, and the pressing operation of the chip 3 by the bonding tool 5 is stopped. As described above, in the present embodiment, by providing the sensor 13 and the dog 5b, the position of the rising end of the bonding tool 5 relative to the elevating member 6 is regulated. Does not exceed 50 kg, which is the sum of the weight of the bonding tool 5 and the load applied by the air cylinder 12. (Description of Operation) In the above configuration, the bonding apparatus 1
Before the joining operation of the chips 3 is started, the pressing load by the bonding tool 5 is input in advance to the above-described control device, and a predetermined load (for example, 40 kg) is added to the load cell 11 by the air cylinder 12. . Here, assuming that the load of the bonding tool 5 itself is 10 kg, a total load of 50 kg is added to the load cell 11 in advance.
g is detected, and the detected load is input to the control device. From this state, the substrate 2 is placed on the positioning stage 4 and the positioning stage 4 is moved in the XY directions by a required amount to position the substrate 2 at a position directly below the bonding tool 5 holding the chip 3. In this state, the motor 8 is operated by the control device to lower the bonding tool 5, so that the chip 3 held at its lower end is superposed on the substrate 2 and pressed. Accordingly, the pressing load on the chip 3 by the bonding tool 5 increases, and the bonding tool 5 is raised relatively to the lifting member 6 against the air cylinder 12. Accordingly, the load detected by the load cell 11 gradually decreases from the initial 50 kg. When the load detected by the load cell 11 becomes 20 kg, the control device stops the operation of the motor 8 at that time and performs bonding. The lowering of the tool 5 is stopped. Thus, the operation of bonding the chip 3 to the substrate 2 by the bonding tool 5 is completed. According to the above-described embodiment, even if the lowering amount of the bonding tool 5 is increased more than necessary for some reason, the detected load by the load cell 11 decreases with the progress of the pressing operation (lowering operation) by the bonding tool 5. . Therefore, the load cell 11 is not damaged by an excessive pressing load. Further, since the bonding tool 5 can be raised and lowered and is supported by being pressed against the load cell 11 by the air cylinder 12, even if the descending amount is increased more than necessary, the bonding tool 5 and the air cylinder are still attached to the substrate 2 and the chip 3. 12, the substrate 2 and the chip 3 are not damaged by excessive pressing load. It should be noted that the dog 5b is brought into contact with the pressing operation (lowering operation) by the bonding tool 5.
Is detected by the sensor 13, the operation of the motor 8 is forcibly stopped, and the lowering of the bonding tool 5 is stopped. This prevents the bonding tool 5 from moving to the rising end relative to the elevating member 6, and prevents a load equal to or greater than the sum of the weight of the bonding tool 5 and the additional pressure by the air cylinder 12 from being applied to the substrate 2 and the chip 3. As a result, damage to the substrate 2 and the chip 3 is prevented. In the above embodiment, a load of 50 Kg is applied to the load cell 11 in advance before the bonding operation is started, and the pressing operation by the bonding tool 5 is started, and when the detected load of the load cell 11 becomes 20 kg, the bonding tool is stopped. 5 is stopped, but a load of 50 kg is applied to the load cell 11 in advance, and when the detected load becomes 0 kg after the pressing operation by the bonding tool 5 is started, the pressing operation by the bonding tool 5 is performed. May be stopped.

[0007]

As described above, according to the present invention, it is possible to obtain an effect that the load cell can be favorably prevented from being damaged when the electronic component is pressed by the bonding tool.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a right side view of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Bonding apparatus 2 Substrate 3 Chip (electronic component) 5 Bonding tool 11 Load cell 13 Sensor

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01L 21/60 311

Claims (3)

(57) [Claims] 1. A bonding apparatus comprising: a bonding tool provided so as to be able to move up and down; and a load cell detecting a load when an electronic component is pressed by the bonding tool, wherein a predetermined load is previously applied to the load cell via the bonding tool. Wherein the load detected by the load cell is reduced when the electronic component is pressed by the bonding tool. 2. The load cell is disposed vertically upward to support the bonding tool, and the predetermined load is applied to the load cell by pressing down the bonding tool downward by an air cylinder directed vertically downward. The bonding apparatus according to claim 1, wherein the bonding is performed. 3. The bonding apparatus according to claim 2, further comprising a sensor for detecting that the bonding tool is separated from the load cell when the bonding tool presses the electronic component.