JPH05291354A - Bonding device - Google Patents

Abstract

PURPOSE:To adjust the parallelism between a tool and a stage extremely simply, and bond inner leads extremely highly accurately without the influence of thermal deformation, the misposition of the stage, etc. CONSTITUTION:An engaging part 23 is provided on the top of a base 20 where a stage 30 is loaded, and an part 31 to be engaged is provided at the center of the bottom of the stage 30, and the part 31 to be engaged is engaged with the engaging part 23, thus the stage 30 is supported tiltably in all directions, centering on the part 23 to be engaged. When the topside 40a of a tool 40 is brought into contact with the placing face 30a of stage 30, the placing face 30a of the stage becomes parallel, according to the inclination of the topside 40a of the tool 40. After adjustment of this parallelism, the inner leads 3a of a film carrier 1 are bonded en bloc to the respective electrodes 10a of the semiconductor chip 10 placed on the placing face 30a of the stage 30, being heated and pressurized by the topside 40a of the tool 40.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bonding apparatus for joining a predetermined portion of a semiconductor chip and a predetermined portion of a lead structure with a stage and a tool, for example, TAB.
The present invention relates to an optimal bonding apparatus for collectively bonding a large number of leads of a film carrier to a large number of electrodes of a semiconductor chip in the method.

[0002]

2. Description of the Related Art Among semiconductor device mounting technologies, as semiconductor devices, a semiconductor chip is mounted on a film carrier formed by forming a large number of leads on a film base material, which is particularly remarkable for increasing the number of leads and miniaturization. TAB (Tape A
utomated Bonding) method is known. The TAB method includes a method in which the leads of the film carrier are collectively bonded to a large number of electrodes of a semiconductor chip. A bonding apparatus for this purpose has conventionally been a stage on which a semiconductor chip is mounted and a stage on which the semiconductor chip is mounted. And a tool driven up and down so as to face each other, and each lead of the film carrier is configured to be collectively bonded to each electrode of the semiconductor chip mounted on the stage by heating and pressing by the tip surface of the tool. There is.

[0003]

A particular problem in the above-mentioned bonding apparatus is the parallelism between the tip surface of the tool and the stage, and high precision is required.
That is, since the leads of the film carrier are extremely thin and fine, if the parallelism is a little misaligned, a bonding failure occurs in which only one side of the semiconductor chip is bonded and the other side is lifted, and Breakage, peeling, etc. become a problem.

Therefore, in the conventional bonding apparatus, the tool has a two-step sliding structure in the front-rear direction and the left-right direction, or the tool is supported by a plurality of links to tilt the tool with respect to the stage. Was being adjusted. However, since the structure of the tool tilt adjusting mechanism such as the two-stage sliding structure and the link mechanism is extremely complicated, and the tool is heated to join by heating and pressing, the temperature of the tool is particularly high. In a complicated structure, an error was likely to occur in tilt adjustment due to thermal deformation. Further, this tilt adjusting mechanism has a problem that the work efficiency is low because it takes a very long time to adjust the tilt.

Therefore, there is one that adjusts the parallelism of the stage with respect to the tip end surface of the tool, but in order to adjust the inclination of this kind of flat plate type stage, usually, the stage is supported at three points by adjusting screws or the like. I was trying. However, in such a stage tilt adjusting mechanism, it is necessary to alternately adjust each adjusting screw, and the adjusting work is extremely troublesome. Moreover, in the structure in which the stage is supported at a plurality of positions, when the stage is thermally deformed, the supporting position also changes, so that an error is likely to occur in the tilt adjustment as described above.

From the above, Japanese Patent Laid-Open No. 3-2159
In Japanese Patent No. 50, a rigid parallel plate is provided on a stage via an elastic body, and during bonding, the elastic action of the elastic body absorbs the inclination of the tip surface of the tool to adjust the parallelism of the rigid parallel plate. I am trying. However, in this structure, the rigid parallel plate is not supported by the rigid body but the parallelism of the rigid parallel plate is obtained by elastic deformation of the elastic body.
Therefore, during bonding, the rigid parallel plate is easily displaced laterally, and it is difficult for the pressure contact force of the tool to be evenly transmitted to the rigid parallel plate. Therefore, there is a problem that the bonding on each side of the semiconductor chip cannot always be performed uniformly and reliably.

In adjusting the parallelism between the tool and the stage, it is necessary to suppress the error on each side within about 3 μm. However, as the size of the semiconductor chip becomes larger, it becomes very difficult to adjust it. For example, when using a semiconductor chip having a side of 15 mm square, conventional parallelism adjustment
The limit was to suppress the error on each side to about 5 μm.

Therefore, the present invention provides a bonding apparatus capable of extremely easily adjusting the parallelism between the tool and the stage, and performing extremely highly accurate bonding without the influence of thermal deformation or the displacement of the stage. The purpose is to provide.

[0009]

In order to achieve the above object, the present invention is directed to a stage on which a component of either a semiconductor chip or a lead structure is placed, and a stage which is driven up and down facing the stage. A bonding tool for bonding a predetermined part of the one part mounted on the stage to a predetermined part of the other part by heating and pressing the tip part of the tool. One engaging portion is provided on the upper surface of the base on which is mounted, and an engaged portion that is engaged with the engaging portion is provided substantially at the center of the lower surface of the stage, and the engaged portion of the stage is By engaging with the engaging portion of the base, the stage is supported so as to be tiltable in all directions around the engaged portion. Also, the present invention comprises a stage on which a semiconductor chip is mounted, and a tool that is vertically driven so as to face the stage, and a film carrier is attached to a large number of electrodes of the semiconductor chip mounted on the stage. In a bonding apparatus for collectively bonding a large number of leads by heating and pressing by the tip end surface of the tool, one engaging portion is provided on the upper surface of a base on which the stage is mounted, and By providing an engaged portion to be engaged with the engaging portion and engaging the engaged portion of the stage with the engaging portion of the base, the stage is moved in all directions around the engaged portion. It is supported so that it can tilt freely. Further, it is preferable to provide stage fixing means for fixing the stage to the base after adjusting the inclination of the stage.

[0010]

According to the present invention constructed as described above, the stage is moved in all directions around the engaged portion by the engagement of the engaging portion of the base and the engaged portion of the stage, with the stage being supported at one point. Can be tilted. Thus, even if the tip surface of the tool is not parallel to the stage, the stage becomes parallel to the inclination of the tip surface of the tool only by pressing the tip surface of the tool onto the stage. Moreover, since the stage is supported at one point, the supporting position does not change even if the stage is thermally deformed. Further, since the supporting state of the stage is a rigid support, the stage is not laterally displaced during bonding, and the pressure contact force of the tool is evenly transmitted to the stage. In the present invention, there is a so-called self-adjusting action in which the stage automatically becomes parallel to the tool only by pressing the tool against the stage, but in the actual bonding work, the inclination of the stage was adjusted in advance. After that, the stage is preferably fixed to the base by the stage fixing means.

[0011]

Embodiments of the bonding apparatus according to the present invention will be described below with reference to the drawings. First, FIG. 1 to FIG.
1 shows an embodiment and is an inner lead bonding apparatus in a TAB method.

In the TAB method, as shown in FIG. 2, the semiconductor chip 10 is mounted on the film carrier 1. The film carrier 1 is composed of a long tape-shaped film base 2 and a large number of leads 3 formed on the film base 2. The film substrate 2 has a device hole 4, an outer lead hole 5 and a sprocket hole 6
Are formed, and the support ring 7 remains between the device hole 4 and the outer lead hole 5. Each lead 3
One end of the inner lead 3 protruding into the device hole 4
The outer lead 3b is bridged to the outer lead hole 5 at the other end. A flexible and insulating film material such as a polyimide resin is used for the film base material 2. After punching the holes 4, 5, 6, etc. in the film base material 2, a film material such as Cu foil is formed. The leads 3 are collectively formed by laminating a conductive metal material and performing photoetching so as to form a predetermined pattern.

Then, each inner lead 3a of the film carrier 1 is collectively bonded to a large number of electrodes 10a formed on the upper surface of the semiconductor chip 10 by a bonding device, and the semiconductor chip 10 is electrically connected to each inner lead 3a. And mechanically retained.

As shown in FIGS. 1 and 2, this bonding apparatus has a base 20 as a base and a base 20.
Each of the electrodes 10a of the semiconductor chip 10 mounted on the stage 30 is provided with a stage 30 mounted on the stage 30 on which the semiconductor chip 10 is mounted, and a tool 40 that is vertically driven to face the stage 30. Then, the inner leads 3a of the film carrier 1 are heated and pressed by the tool 40 to be bonded together. In addition, the bonding apparatus as a whole has a transport mechanism for transporting the film carrier 1 and the semiconductor chip 10, a positioning mechanism for performing both alignments, a discharging mechanism after bonding, a control means for controlling each mechanism, and the like. However, these explanations are omitted.

First, the base 20 has a square block shape, and the inside of the outer peripheral wall portion 21 is a recess 22 for accommodating the stage 30. An upper surface of the recess 22 is formed in a conical shape, and an engaging portion 23 formed of a conical sharp projection is provided in the center thereof.

Next, the stage 30 has a square plate shape, and the upper surface thereof is a flat mounting surface 30a on which the semiconductor chip 10 is mounted. An engaged portion 31 formed of a conical concave portion is provided at the center of the lower surface of the stage 30.

The engaged portion 31 of the stage 30 is engaged with the engaging portion 23 of the base 20 so that the stage 30 is supported by the engaging portion 23 at one point. It is supported so as to be tiltable in all directions around the engaging portion 31.

The engaging portion 23 and the engaged portion 31 are not limited to the conical convex portions and concave portions described above, but may be constituted by, for example, hemispherical convex portions and concave portions. Also, the engaging portion 2
It is also possible to reverse the engagement state of 3 and the engaged portion 31. Further, the engaging portion 23 and the engaged portion 31 are attached to the base 2
It may be provided not by directly forming it on the stage 0 and the stage 30, but by fitting another member or the like. The engaging portion 23 and the engaged portion 31 are preferably subjected to heat treatment or using cemented carbide or the like to minimize wear.

Further, fixing screws 24 are horizontally screwed to each side of the outer peripheral wall portion 21 of the base 20 as stage fixing means, and by tightening these screws 24, their tips are fixed. The stage 30 is configured so as to be brought into contact with the side surface of the stage 30 so that the stage 30 can be fixed in a predetermined inclined state.

Further, a plurality of springs 25 are arranged in the recess 22 of the base 20, and these springs 25 abut against the lower surface of the stage 30 to cause the stage 30 to move more than necessary before adjusting the inclination. It is configured so that it does not rock.
Since each spring 25 is for preventing excessive swing of the stage 30, its spring force is extremely weak.

Next, the tool 40 has a tip surface 40a.
Has a flat bonding surface. Then, the tool 40 is moved up and down by a drive mechanism (not shown),
The tilt can be roughly adjusted.

In the inner lead bonding apparatus constructed as described above, first, as shown in FIG.
The standard stage 50 is used to roughly adjust the tilt of the tool 40. The reference surface 50a of the standard stage 50 has substantially the same degree of parallelism as the bottom surface of the base 20. This reference plane 50a
A film 51 such as a polyimide resin is placed on the tool 40, the tool 40 is lowered, and the tip surface 40a of the tool 51 lowers the film 51.
Is pressed to make indentations, and the inclination of the tool 40 is adjusted so that the indentations are formed substantially uniformly. It should be noted that this adjustment is a very simple rough adjustment that only corrects an unnecessary tilt of the tool 40, and the tool 40 is fixed after the adjustment.

Next, as shown in FIG. 4, the standard stage 5
0 is replaced with the base 20 having the stage 30 of this embodiment. Then, the tool 40 is lowered and its tip surface 40
a is brought into contact with the mounting surface 30a of the stage 30. Since the stage 30 is tiltable in all directions around the engaged portion 31, the stage 30 is tilted corresponding to the tilt of the tip surface 40a of the tool 40, and the stage 30 is tilted relative to the tip surface 40a of the tool 40. The mounting surface 30a becomes exactly parallel.

As described above, the parallelism of the stage 30 with respect to the tool 40 can be easily adjusted in an extremely short time because the tool 40 is merely pressed against the stage 30. In addition, since the stage 30 is held in a substantially horizontal state by the spring 25 interposed between the base 20 and the stage 30, before the tool 40 is brought into contact with the stage 30,
It is possible to prevent a large impact from occurring when the tool 40 is brought into contact.

After adjusting the inclination of the stage 30 as described above, the fixing screw 24 is tightened in the inclined state to fix the stage 30 to the base 20.

In the bonding apparatus in which the parallelism is adjusted as described above, the semiconductor chip 10 is mounted on the mounting surface 30a of the stage 30 as shown in FIG.
The heated tool 40 is lowered, and the inner surface 3a of the film carrier 1 heats and presses the inner leads 3a of the film carrier 1 to be bonded to the electrodes 10a of the semiconductor chip 10. It should be noted that this bonding is performed via bumps provided on each electrode 10a or transfer bumps provided on each inner lead 3a.

Since the stage 30 is supported at one point during this bonding, the supporting position does not change even if the stage 30 is thermally deformed. Further, since the supporting state of the stage 30 is a rigid support, the stage 30 is not displaced laterally, and the pressure contact force of the tool 40 is reliably transmitted to the stage 30. Therefore, even in the case of a large-sized semiconductor chip 10, it is possible to suppress an error in parallelism on each side within 3 μm, for example, and each electrode 10a and each inner lead 3a are bonded to each other extremely uniformly and reliably. be able to.

In the present embodiment, the semiconductor chip 10 placed on the stage 30 may be held by vacuum suction using a pump or the like. Further, in this embodiment, after adjusting the parallelism of the stage 30, the stage 30 is fixed to the base 20 by the fixing screw 24. However, as is clear from the above description, the tool 40 is pressed against the stage 30. Since the parallelism is adjusted only by itself, the self-adjustment action of automatically adjusting the inclination of the stage 30 each time bonding is performed may be used without fixing the stage 30.

Next, FIG. 5 shows a second embodiment, which is a die bonding apparatus for bonding a semiconductor chip to a lead frame. The structure of the bonding apparatus itself is substantially the same as that of the first embodiment, and the same parts are designated by the same reference numerals and the description thereof is omitted.

In this bonding apparatus, the lead frame 60 is mounted on the mounting surface 30a of the stage 30, and the mount portion 6 at the substantially center of the lead frame 60 is mounted.
The semiconductor chip 10 is pressed onto the substrate 1 by the tool 40 and scrubbed (rubbed) for several seconds.
Are joined. The tool 40 in this case is configured to hold the semiconductor chip 10 by vacuum suction or the like.

Also in such a die bonding apparatus, similarly to the inner lead bonding apparatus, the stage 30 which can be tilted in all directions in a single-point supported state is used to mount the mounting surface 30a of the stage 30 with respect to the tip surface 40a of the tool 40. The parallelism can be adjusted extremely easily and highly accurately. As a result, the mounting portion 61 of the lead frame 60 and the back surface of the semiconductor chip 10 can be bonded extremely uniformly and reliably over the entire surface, and accidental peeling of the semiconductor chip 10 can be prevented. ..

Further, especially in the case of a die bonding apparatus,
The stage 30 is heated to a high temperature in order to heat the lead frame 60 to a predetermined temperature.
Has very little effect of thermal deformation. Furthermore, when the semiconductor chip 10 is scrubbed by the tool 40, the stage 30 follows the tool 40 extremely smoothly.

The embodiments of the present invention have been described above.
The present invention is not limited to the above embodiments, and various effective modifications and applications are possible based on the technical idea of the present invention. For example, the one-point support structure of the stage may have various configurations other than the embodiment, and the shape of the stage may be changed to a circular plate shape or the like. Further, in the embodiment, the inner lead bonding apparatus in the TAB method and the die bonding apparatus using the lead frame have been described. However, the present invention connects a large number of leads connected to a semiconductor chip to a lead structure such as a wiring board. The present invention can be applied to various bonding apparatuses such as an outer lead bonding apparatus that bonds a predetermined portion of a semiconductor chip and a predetermined portion of a lead structure with a stage and a tool.

[0034]

As described above, according to the present invention,
The engaged portion provided in the substantially center of the lower surface of the stage is engaged with the engaging portion provided on the upper surface of the base, and the stage is supported in a single point support state so as to be tiltable in all directions around the engaged portion. By just pressing the tip surface of the tool onto the stage, the stage becomes parallel according to the inclination of the tip surface of the tool, making it easy to adjust the parallelism between the tool and the stage in an extremely short time. This improves the work efficiency. Moreover, according to the present invention, by supporting the stage at one point, it is possible to prevent a change in the supporting position due to thermal deformation of the stage, unlike the supporting structure at a plurality of positions. Since the stage is supported by the rigid body, unlike the configuration in which the elastic body is interposed between the base and the stage, the stage can be prevented from being displaced in the lateral direction during bonding, and the tool can be prevented. It is possible to evenly transmit the pressure contact force of the to the stage. Therefore, the predetermined portion of the semiconductor chip and the predetermined portion of the lead structure can be bonded extremely uniformly and reliably, and the reliability of bonding can be significantly improved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a main part at the time of bonding in a first embodiment in which the present invention is applied to an inner lead bonding apparatus in a TAB method.

FIG. 2 is an exploded perspective view of a main part of the apparatus of the above embodiment.

FIG. 3 is a vertical cross-sectional view of a main part when the inclination of the tool is roughly adjusted by the apparatus of the embodiment.

FIG. 4 is a vertical cross-sectional view of a main part when the parallelism of the stage is adjusted by the apparatus of the embodiment.

FIG. 5 is a vertical cross-sectional view of a main part at the time of bonding in a second embodiment in which the present invention is applied to a die bonding apparatus using a lead frame.

[Explanation of symbols]

 1 Film Carrier 2 Film Base Material 3 Lead 3a Inner Lead 10 Semiconductor Chip 10a Electrode 20 Base 23 Engagement Part 24 Fixing Screw 25 Spring 30 Stage 30a Mounting Surface 31 Engaged Part 40 Tool 40a Tip Surface 50 Standard Stage 60 Lead Frame 61 Mount section

Claims (3)

[Claims] 1. A stage, on which a component of either a semiconductor chip or a lead structure is placed, and a tool, which is driven up and down so as to face the stage, and which is placed on the stage. In a bonding apparatus for joining a predetermined part of one part to a predetermined part of the other part by heating and pressurizing the tip surface of the tool, one engaging part is provided on an upper surface of a base on which the stage is mounted. The stage is provided with an engaged portion to be engaged with the engaging portion substantially at the center of the lower surface of the stage, and the stage is provided with the engaged portion of the stage by engaging the engaged portion of the base. A bonding apparatus, which is supported so as to be tiltable in all directions around an engaged portion. 2. A stage on which a semiconductor chip is mounted,
A tool that is driven up and down so as to face the stage, and a large number of leads of the film carrier are heated and pressed by the tip end surface of the tool to a large number of electrodes of the semiconductor chip mounted on the stage. In a bonding apparatus for joining, one engaging portion is provided on an upper surface of a base on which the stage is mounted, and an engaged portion to be engaged with the engaging portion is provided at substantially the center of a lower surface of the stage, A bonding apparatus, wherein an engaged portion of a stage is engaged with an engaging portion of the base, whereby the stage is supported so as to be tiltable in all directions around the engaged portion. 3. The bonding apparatus according to claim 1, further comprising stage fixing means for fixing the stage to the base after adjusting the inclination of the stage.