JPH0487347A - Bonding apparatus - Google Patents

Abstract

PURPOSE:To efficiently execute an operation to adjust the parallelism by a method wherein a holding part and a mounting stand are formed in such a way that the pressurization face of a pressure means and the face on which an object to be pressed is mounted of the mounting stand become parallel, the rear surface of the holding part is brought into contact with the peripheral part on the surface of the mounting stand and the body to be pressed is pressed. CONSTITUTION:Since springs 26 are installed at the lower part of a mounting stand 22, the springs 26 are deformed elastically by a force by which the rear surface 14a of a pressurization head 14 presses the surface of the mounting stand 22. Even when the pressurization head 14 is tilted with reference to the horizontality, the peripheral part 22b on the surface of the mounting stand 22 automatically follows the rear surface 14a of the pressurization head 14 so as to come into contact with the rear surface. At this stage, the parallelism between the pressurization face 12a of a bonding tool 12 and the mounting face 22a of the mounting stand 22 is maintained. The parallelism between the pressurization face 12a and the mounting face 22a is ensured in this manner. After that, the bonding tool 12 is lowered. Thereby since the pressurization face 12a is lowered by keeping the parallelism with the mounting face 22a of the mounting stand 22, a uniform load is applied on discrete electrodes of an IC chip 32 and on bumps of a lead.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a bonding device used for bonding, for example, an electrode of an IC chip and a lead of a TAB tape.

[Conventional technology]

Various methods are used to connect the electrodes of the IC chip and external leads.

There is a method of connecting using ultra-thin wiring wire (bonding wire), but another widely used method is to sandwich a fine metal ball (hereinafter referred to as a bump) between the electrode of the IC chip and the lead and bond them by thermocompression. It looks like this.

TA B (Tape Automated Bond
ing) method is a technique that is attracting attention as a representative of the latter. In this method, the electrodes of the IC chip or T
A bump is formed on one of the lead tips on the AB tape, and then a bump is formed on one of the lead tips on the AB tape, and then the TA with the electrode and lead of the IC chip is formed.
The B tape is overlapped with the B tape via a bump to join them together. In the TAB method, a large number of electrodes and leads can be bonded all at once, which enables rapid bonding work.

[Problem to be solved by the invention]

FIG. 2 is a schematic diagram of a conventional bonding device. Second
The bonding apparatus shown in the figure includes a bonding tool 52 that is held movably up and down, and an R'1 stand 54 on which an IC chip 62 and the like are placed. In the figure, 64 is a TAB tape, and 66 is a bump.

In order to uniformly and accurately bond a large number of electrodes and leads arranged in a substantially square shape using a bonding device, the pressure surface 52a of the bonding tool 52 that presses them during bonding is placed on the IC chip 62 of the mounting table 54. The surface on which you place the (
Hereinafter, it will also be referred to as a mounting surface. ) 54a in parallel.

However, in the conventional bonding apparatus, the bonding tool 52 and the mounting table 54 on which the IC chip 62 and the like are placed are each fixed separately, and the bonding device tends to bond the IC chip 62 of about 1 cm square. The pressing surface 52a of the bonding tool 52 and the mounting surface 54a of the mounting table 54 have a small area. Therefore, due to external factors such as vibrations, the parallelism between the pressurizing surface 52a of the bonding tool 52 and the first surface 54a of the mounting table 54 may deviate during pressurization, or the position of the bonding tool 52 and the mounting table 54 in the lateral direction may shift. There were times when a discrepancy occurred. In addition, due to long-term use, the pressure surface 52a of the bonding tool 52 and the R stand 54
There is a problem that the parallelism with the mounting surface 543 tends to shift easily. If the pressure surface 52a of the bonding tool 52 and the mounting surface 54a of the mounting table 54 are not parallel to each other in this way, the Ic chip 62 and the T A, B tape 64 may be damaged due to poor bonding.
The yield rate when joining the two will be poor.

Furthermore, when the IC chip 62 and the TAB tape 64 are bonded together, the bumps 66 are only deformed by about 5 μm. Therefore, even if the parallelism between the pressure surface 52a and the mounting surface 54a deviates to an extreme value, a bonding failure will occur, so the pressure surface 52a
The parallelism between the mounting surface 54a and the mounting surface 54a must be maintained with high precision. However, in the conventional bonding apparatus, as described above, the pressure surface 52a of the bonding tool 52 and the mounting surface 54a of the mounting table 54 are approximately the same size as the IC chip 62. There was a problem in that the narrow planes had to be adjusted so as to maintain parallelism with each other, and the adjustment work was time-consuming.

The present invention has been made based on the above circumstances, and an object of the present invention is to provide a bonding device that can efficiently perform the work of adjusting parallelism, and can also perform bonding reliably and improve yield. That is.

[i! ! ! Means to solve the problem]

A bonding device for achieving the above object includes a pressing means, a holding part for holding the pressing means, and a mounting table disposed opposite to the pressing surface of the pressing means and on which a pressed object is placed. In a bonding device comprising:
The holding part is formed to slidably hold the pressing means, and a moving means for moving the holding part is provided, and when the holding part is moved by the moving means, a conveyance path of the object to be pressed is removed. When the lower surface of the holding part and the peripheral part of the upper surface of the mounting table are in contact with each other, and the lower surface and the peripheral part are in contact with each other, the pressing surface of the pressing means and the object to be pressed of the mounting table are placed. The holding part and the mounting base are formed so that their surfaces are parallel to each other, and after the lower surface of the holding part is brought into contact with the periphery of the upper surface of the mounting base by the moving means, the holding part is pressed by the pressing means. It is characterized in that it is configured to press a pressing body.

Preferably, at least one of the holding section and the mounting table is supported via an elastic member.

[Effect]

With the above configuration, the present invention first moves the holding part to bring the lower surface of the holding part into contact with the peripheral part of the upper surface of the mounting table. This allows the holding unit and i! The mounting table is integrated, and the pressing surface of the pressing means and the surface of the mounting table on which the object to be pressed is placed (ml!! placement surface) are kept parallel. In this state, by lowering the pressing means, a uniform load is applied to the pressed body placed on the mounting table while the pressing surface of the pressing means and the mounting surface of the mounting table maintain parallelism. By forming the holding portion and the mounting table so that the abutting surfaces thereof are large, it is possible to easily adjust the parallelism between the pressing surface of the pressing means and the mounting surface of the mounting table.

By configuring at least one of the holding part and the mounting table to be supported via an elastic member, for example, when the elastic member is provided on the mounting table side, the holding part is elastic by the pressing force that presses the mounting table. By elastically deforming the member, the upper surface of the mounting table automatically follows the lower surface of the holding part, and the holding part and the mounting table become integrated. Thus, for example, when the holding part is tilted with respect to the horizontal, the mounting table automatically tilts to follow the holding part, and the parallelism between the pressing surface of the pressing means and the mounting surface of the mounting table is automatically maintained.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a schematic front view of a bonding apparatus that is an embodiment of the present invention. In this embodiment, a case will be described in which an IC chip is bonded to a TAB tape in which bumps are thermocompression bonded to lead tips.

The bonding device shown in FIG. 1 includes a pressing device 2 having a bonding tool (pressing means) 12 and a pressing head (holding section) 14 that holds the bonding tool 12.
The receiver provided opposite the pressing device 2 includes a device 4. The tip of the bonding tool 12 is heated to 500°C.
It has a built-in heater (not shown) for heating. A helical bearing 16 that slidably holds the side surface of the bonding tool 12 is provided inside the lower part of the pressurizing rod 14. The receiver device 4 includes a mounting table 22 on which the IC chip 32 is placed, and a plurality of springs (elastic members) 26 provided at the bottom of the mounting table 22.

The pressure head 14 and the mounting table 22 are connected to each other when the lower surface 14a of the pressure head 14 and the peripheral part 22b of the upper surface of the mounting table 22 come into contact with each other. The mounting surface 22a on which the rc chip is mounted is parallel to the mounting surface 22a. That is, in this embodiment, the pressure surface 12a of the bonding tool 12, the lower surface 14a of the pressure head 14, and the peripheral portion 22 of the lower surface of the mounting table 22
b and the mounting surface 22a of the mounting table 22 are formed parallel to each other. A knock bottle 18 is formed on the lower surface 14a of the pressure head 14, and a recess 28 corresponding to the knock bottle 18 is formed on the peripheral portion 22b of the upper surface of the mounting table 22.

The knock pins 18 and the recesses 28 are used to ensure alignment in the lateral direction as shown in the figure, and also to prevent displacement in the lateral direction between the pressing surface 12a and the mounting surface 22a during pressurization.

In addition, in the space between the mounting table 22 and the bonding tool 12, there is a T with a bump that moves in a direction perpendicular to the plane of the drawing.
AB tape 34 is placed.

Incidentally, in this embodiment, when bonding the IC chip 32 and the TAB tape, bumps that are all formed to have a uniform size are used. This is a technology that was previously filed by the present applicant (Japanese Patent Application No. 1-320296), in which the metal that is the raw material for bumps is processed into fine wires, and then the metal wires are cut to a specified length to create a bond between each other. It can be easily formed by melting and solidifying the bumps in a state where they are separated and obtaining a uniform spherical bump using surface tension.

In order to join the electrodes of the Ic chip 32 and the leads of the TAB tape 34, first use a lift (not shown)! The pressing device 2 is lowered by the device (moving means), the knock bottle 18 is fitted into the recess 28, and the lower surface 14a of the pressing head 14 and the peripheral portion 22b of the upper surface of the mounting table 22 are brought into contact with each other. 4. At this time, since a spring 26 is provided at the bottom of the mounting table 22, the pressure head 14
By elastically deforming the spring 26 due to the force of the lower surface 14a pushing the upper surface of the mounting table 22, even if the pressurizing rod 14 is inclined with respect to the horizontal, the periphery of the upper surface of the mounting table 22 The portion 22b automatically follows so as to come into contact with the lower surface 14a of the pressure head 14. At this stage, the pressure surface 12a of the bonding tool 12 and! ! The parallelism with the mounting surface 22a of the mounting table 22 is maintained. By lowering the bonding tool 12 after ensuring the parallelism between the pressurizing surface 12a and the mounting surface 22a in this way, the pressurizing surface 12 of the bonding tool 12. a descends while remaining parallel to the mounting surface 22a of the mounting table 22, so that a uniform load is applied to the bonding surface between each electrode of the Ic chip 32 and the bump of the lead. In this way, a large number of leads provided on one frame of the TAB tape 34 and the electrodes of the IC chip 32 are bonded together. When one IC chip 32 is bonded, the frame of the next TAB tape is transported directly below the bonding tool 12 by a TA'B tape feeding mechanism (not shown), and another IC chip is transported by a transport device (not shown). ) onto the mounting table 22, and the above bonding operation is repeated.

In the bonding apparatus of this embodiment, the pressing device 2 and the receiver 4 are connected to the lower surface 14a of the pressing surface 4, which is a larger plane than the pressing surface 12a and the mounting surface 22a, and the peripheral portion 22b of the upper surface of the mounting table 22. Since joining is performed after abutment and integration, even if an external factor such as vibration occurs during joining, the parallelism will not be impaired and the joining can be performed reliably.

Therefore, the parallelism between the pressure surface 12a and the mounting surface 22a can be stably maintained even during long-term use.

Furthermore, according to this embodiment, the force applied to the bonding surface between each electrode of the IC chip and the bump of the lead is uniform, so that these bonds can be reliably performed, reducing bonding defects and reducing the number of defects during bonding. The yield can be improved. Further, since the parallel adjustment between the pressurizing surface of the bonding tool and the mounting surface of the mounting table is automatically performed, it is possible to improve work efficiency.

In addition, in the above embodiment, the elastic member (spring)
Although the case has been described in which the spring is provided at the lower part of the mounting table, the present invention is not limited to this. For example, the spring may be provided at the upper part of the pressure head. Furthermore, in the present invention, there is no need to provide a spring, and even if a spring is not provided, the lower surface 14a of the pressure head 14 and the peripheral portion 22b of the upper surface of the mounting table 22 are wider than the pressure surface of the bonding tool. Pressure surface 12a and 'RW surface 2
2a, the pressure surface 12a of the bonding tool 12 and the mounting surface 22 of the mounting table 22 can be adjusted.
It becomes extremely easy to adjust the parallelism with a. Furthermore, compared to conventional bonding apparatuses, the parallelism between the pressurizing surface of the bonding tool and the mounting surface of the mounting table can be easily maintained with high precision.

Further, in the above embodiment, a case was explained in which a spring was used as the elastic member, but the present invention is not limited to this, and a rubber tube filled with liquid or the like may be used as the elastic member. good.

Further, in the above embodiment, the case where the pressure head moves up and down has been described, but the pressure head may be moved in a direction perpendicular to the plane of the paper of FIG. 1.

In addition, in the above embodiment, the case where the leads of the TAB tape on which bumps have already been formed and the electrodes of the IC chip are bonded, but the present invention is not limited to this, and the present invention is not limited to this. This device can be used to join a TAB tape with a lead when a bump is formed on the electrode side, and also to thermocompress the bumps all at once to the tip of a TAB tape lead. Therefore, this bonding device can be used twice in the process of manufacturing the bumped TAB tape and the process of bonding the TAB tape and the IC chip.

〔Effect of the invention〕

As explained above, according to the present invention, the parallelism between the pressing surface of the pressing means and the mounting surface of one mount can be easily adjusted with high precision by the lower surface of the wide holding part and the peripheral part of the upper surface of the mount. Therefore, it is possible to provide a bonding apparatus that can improve the efficiency of adjustment work and improve the yield when bonding, for example, an IC chip and a TAB tape via bumps.

[Brief explanation of drawings]

FIG. 1 is a schematic front view of a bonding device according to an embodiment of the present invention, and FIG. 2 is a schematic diagram of a conventional bonding device. 2... Pressing device, 4. Receiving device, ] 2... Bonding tool, 12a... Pressing surface, 14... Pressing head, 14a...
... lower surface of pressure head, 16 ... sliding bearing, 18 ... knock bottle, 22 ...
... Mounting table, 22a... Placement surface, 22b... Peripheral part of the top surface of the placing table, 26... Spring, 28... Concave part, 32...
IC chip, 34...TAB tape.

Claims (2)

[Claims] (1) A bonding device comprising a pressing means, a holding part for holding the pressing means, and a mounting table disposed opposite to the pressing surface of the pressing means and on which a pressed object is placed, The holding part is formed to slidably hold the pressing means, and a moving means for moving the holding part is provided, and when the holding part is moved by the moving means, a conveyance path of the object to be pressed is removed. When the lower surface of the holding part and the peripheral part of the upper surface of the mounting table are in contact with each other, and the lower surface and the peripheral part are in contact with each other, the pressing surface of the pressing means and the object to be pressed of the mounting table are placed. After the holding part and the mounting base are formed so that the surfaces thereof are parallel to each other, and the lower surface of the holding part is brought into contact with the peripheral part of the upper surface of the mounting base by the moving means,
A bonding device characterized in that the pressing means is configured to press a pressed body. (2) The bonding device according to claim 1, wherein at least one of the holding portion and the mounting table is supported via an elastic member.