JPH04277641A - Outer lead bonding apparatus - Google Patents

Abstract

PURPOSE:To improve the quality of an outer lead bonding, and to provide and inexpensive bonding apparatus by arranging an outer lead bonding apparatus in such a manner that the lead of a semiconductor chip is correctly and readily aligned with the bonding pattern of a circuit board when they are integrally bonded together. CONSTITUTION:An outer lead bonding apparatus is composed of at least a flat fixture 1, which carries a semiconductor chip 5 in contact with the center and periphery of the chip so as to avoid contact with a lead 50, and a thermo- tool 2 with notched corners. The bonding apparatus effects the integrated bonding of the lead 50 with a bonding pattern 60 by means of the therom-tool 2 after the direct confirmation that the bonding pattern 60 of a circuit board 6 is in alignment with the lead 50 of the semiconductor chip 5.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outer lead bonding apparatus. Specifically, when connecting the leads of a semiconductor chip having tab leads and the bonding pattern of the circuit board at once, the leads of the semiconductor chip and the bonding pattern of the circuit board are accurately aligned, and
The present invention relates to an outer lead bonding device configured to facilitate bonding.

0002

[Prior Art] As an outer lead bonding method for connecting the leads of a semiconductor chip having tab leads to the bonding pattern of a circuit board, a so-called gang bonding method is often used, in which a thermometer tool is used to connect the leads all at once. .

FIG. 6 is a diagram showing an example of a conventional outer lead bonding device, in which (a) shows the configuration of the main parts of the device, and (b) shows the structure of the semiconductor chip sucked into the suction nozzle of the vacuum suction device. FIG. 3C shows the arrangement of the thermo-tool and the arrangement of the bonding pattern on the circuit board.

The semiconductor chip 5 has a suction port 1 opened at the tip of a suction nozzle 1' housed in a thermodic tool 2'.
The lead 50 is held under negative pressure by air suction as shown by the arrow at 0', and the image of the lead 50 is observed by the positioning detection camera 3b with a microscope and the TV monitor 4 [see the figure (
b) and (b)]. Normally, in this state, the thermodic tool 2' is heated to 300 to 400° C. by, for example, a cartridge heater (not shown).

On the other hand, stage 7, for example, X, Y, θ
An enlarged image 60' of the bonding pattern 60 is displayed on the screen of the circuit board 6 placed on the 3-axis fine movement stage by the alignment detection camera 3a with a microscope and the TV monitor 4 at a position different from the thermodo tool 2'. Image observation is performed above [Figures (A) and (C)]. Both observations are switched with a switch 8 so that they can be observed alternately.

In this way, by observing the images of both, the semiconductor chip 5 and the circuit board 6, that is, the leads 50 are
The mutual positions of the bonding pattern 60 and the bonding pattern 60 are measured and stored by image processing, and one of the two, for example,
The stage 7 on which the circuit board 6 is placed is mechanically moved by the previously observed and memorized distance in the direction of the arrow, that is, to the left, and is placed under the thermodic tool 2', that is, as indicated by the dotted line. Fix it in a certain position.

[0007] When the positioning is completed, the thermodic tool 2' heated to about 400° C. is lowered, for example, 1
For a tool with a size of 5 mm x 15 mm, 30 k
The lead 50 and the bonding pattern 60 are bonded together by applying a pressure of about 100 g to the bonding pattern.

[0008]

However, in the conventional outer lead bonding apparatus described above, the leads 50 of the semiconductor chip 5 and the bonding pattern 60 of the circuit board 6 are image-recognized separately. Therefore, after the movement, both are hidden behind the thermodo tool 2' and cannot directly observe their overlapping state, and they are connected all at once by the thermodo tool 2'. In this case, it is difficult to completely match the movement amount calculation data based on pattern recognition on the TV monitor 4 and the actual movement position of the stage 7, which causes bonding failures to occur frequently. In addition, there are many problems such as a significant increase in device cost in order to improve accuracy, and solutions are required.

[0009]

[Means for Solving the Problems] The above problem is solved by an outer lead bonding apparatus for collectively connecting leads 50 of a semiconductor chip 5 having tab leads to a bonding pattern 60 of a circuit board 6. It is equipped with at least a planar fixture 1 that is held at a corner portion and a center portion thereof, and a thermode tool 2 that has a notch portion 20 at a corner portion. This problem can be solved by using an outer lead bonding apparatus configured to connect the leads 50 and the bonding pattern 60 together using the thermodo tool 2 after directly confirming the alignment with the outer lead. Specifically, the planar fixture 1 has a suction port 10 that sucks the central portion of the semiconductor chip 5, and is arranged so as to be connected to the suction port 10 and located above the corner portion of the semiconductor chip 5. This can be effectively solved by including at least a small-diameter suction path 11, or by having the planar fixture 1 include a clamp mechanism 100 that holds the semiconductor chip 5 at a plurality of corners.

0010

[Operation] According to the present invention, the leads 50 of the semiconductor chip 5
Since the connection operation is started after directly observing and confirming the degree of overlap between the bonding pattern 60 and the bonding pattern 60 of the circuit board 6 using an alignment detection camera and a TV monitor, mutual positioning is performed extremely reliably, and moreover, it is easy to use the equipment. It also has a relatively simple configuration and is easy to handle.

[0011]

[Embodiment] Figure 1 is a diagram showing an embodiment of the present invention.
Figure (a) schematically shows the state during the alignment operation, and Figure (b) schematically shows the state during the bonding operation.

In the figure, 1 is a flat fixture, for example,
Made of invar with a small coefficient of thermal expansion, the outer diameter is 100.
The size is about mm□ and 3 mm thick. A suction port 10 for sucking the semiconductor chip 5 is opened in the center thereof, and four wires each having an outer diameter of 1 mmφ are placed at the corners where the leads 50 of the semiconductor chip 5 are not present, that is, at positions corresponding to the four corners. A pipe-shaped small diameter suction path 11
A suction path 1 that connects to a vacuum device (not shown) via
Connected to 2. The lead 50 of the semiconductor chip 5 drawn between the peripheral edge and the center, that is, the suction port 10
A gap is open only in the area where the rim exists, and the two, that is, the periphery and the center are connected by small diameter suction passages 11 provided at the four corners.

Reference numeral 3 denotes a positioning detection camera, which is equipped with a magnification optical system of about 6 to 10 times and an image pickup device, and a TV monitor 4.
The system is designed to provide a 120- to 200-fold enlarged image on the display.

Reference numeral 2 denotes a thermo tool made of a heat-resistant metal such as Inconel, and has notches 20 at the four corners for escaping the small diameter suction path 11 during thermocompression bonding.

[0015] Parts equivalent to those explained in the above drawings are designated by the same reference numerals, and explanations of the same parts will be omitted. Now, the bonding pattern of the circuit board 6 made of ceramic, for example, placed on the stage 7 in FIG. The images captured by the superimposition and alignment detection camera 3 are displayed on the TV monitor 4.
Enlarged display on the display. This enlarged image is identified with the naked eye or as electrical signal information, and the stage 7 performs fine adjustment to confirm position matching.

[0016] Once the alignment of both has been confirmed, the same figure (
As shown in b), move the alignment detection camera 3 to a position where it does not get in the way, lower the thermode tool 2 heated to about 400°C, and place the head part on the lead 50 with the required pressure. Then, the bonding pattern of the circuit board 6 and the leads 50 of the semiconductor chip 5 are collectively bonded by thermocompression.

[0017] In the batch thermocompression bonding using the apparatus of the present invention as described above, almost no misalignment occurs after bonding, and the reliability of bonding is greatly improved. Moreover, the apparatus has a simple configuration and is easy to operate, and the time during which the semiconductor chip 5 is sucked into the thermodic tool 2 is short, so there is an advantage that it is less affected by thermal stress.

FIG. 2 is a diagram (part 1) showing the main parts of the embodiment of the present invention, and clearly shows the state in which the semiconductor chip 5 is attracted to the planar fixture 1. The figure (A) is a plan view, the figure (B) is a sectional view from A-A, and the figure (C) is a B-
It is a sectional view of B.

Note that the same reference numerals are given to the same parts as those explained in the above drawings, and the explanation of the same parts will be omitted. From the figure, it is clearly understood how the small-diameter suction passage 11 is arranged in the gap between the peripheral part and the central part.

Furthermore, in the figure, the small diameter suction passages 11 are provided at all four corners of the semiconductor chip 5, but there may be three or less. FIG. 3 is a diagram (part 2) showing the main parts of the embodiment of the present invention, and is an enlarged perspective view of the head portion of the thermodo tool 2. As shown in FIG.

The shaded area on the lower end surface of the head is a bonding contact area. Cutouts 20 are formed at the four corners, through which the small diameter suction path 11 of the planar fixture 1 escapes. Although the figure shows a case where the head part is square, it may be rectangular, and the small diameter suction path 1 of the flat fixture 1
Corresponding to the number 1, they may be provided not at all four corners but at three or less corners.

FIG. 4 is a diagram showing another embodiment of the present invention; FIG. 4A is a partially enlarged plan view, and FIG. One corner portion is shown. The same applies to other corner portions.

In this embodiment, the small-diameter suction path 11 is not constructed of a pipe-like material, but is made of two plates, for example one of which has a required groove and is pasted together to form a flat fixture. 1 is formed, and is suitable for making the entire structure simpler and thinner than the one shown in FIG.

Although the above embodiments all use a vacuum suction method, other holding methods may also be used. For example, FIG. 5 is a diagram showing still another embodiment of the present invention, in which (A) is a partially enlarged plan view and FIG. Indicated. The same applies to other corner portions.

A major feature of this embodiment is that a mechanical clamping method is used. That is, the semiconductor chip 5 is clamped at a corner where the leads 50 are not present. For example, a clamp mechanism 100 configured to be pressable by a spring or the like (not shown) and having a notch at its tip is symmetrically pressed and held against, for example, the four corners of the semiconductor chip 5. As shown in the figure (b), the clamp mechanism 100 has a thickness of, for example, 3 mm.
As shown below, it can be seen that the four corners together constitute a planar fixture as a whole.

[0026] The above embodiments are merely examples, and the materials used, detailed structure,
It goes without saying that other dimensions, shapes, etc., or a combination thereof may be selected and used as appropriate.

[0027]

As explained above, according to the present invention, the degree of overlap between the leads 50 of the semiconductor chip 5 and the bonding pattern 60 of the circuit board 6 can be confirmed by directly observing the alignment detection camera and the TV monitor. Since the connection operation is started after the initialization, mutual positioning is performed extremely reliably. Moreover, the device has a relatively simple configuration and is easy to handle.
Improved yield, accuracy and reliability of outer lead bonding, which connects semiconductor chip leads with tab leads to bonding patterns on circuit boards, as well as
This greatly contributes to lowering the cost of equipment.

[Brief explanation of the drawing]

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

FIG. 2 is a diagram (part 1) showing the main parts of the embodiment of the present invention.

FIG. 3 is a diagram (Part 2) showing the main parts of the embodiment of the present invention.

FIG. 4 is a diagram showing another embodiment of the present invention.

FIG. 5 is a diagram showing still another embodiment of the present invention.

FIG. 6 is a diagram showing an example of a conventional outer lead bonding device.

[Explanation of symbols]

1 is a flat fixture; 2 is a thermod tool, 3 is a positioning detection camera; 4 is a TV monitor, 5 is a semiconductor chip; 6 is a circuit board; 7 is the stage, 10 is a suction port; 11 is a small diameter suction path; 12 is a suction path; 20 is a notch, 21 is a bonding contact part; 50 is lead, 60 is a bonding pattern, 100 is a clamp mechanism;

Claims (3)

[Claims] [Claim 1] A semiconductor chip (5
In an outer lead bonding device that collectively connects the leads (50) of ) to the bonding patterns (60) of the circuit board (6), the semiconductor chip (5) is held at the corner parts and the center part where the leads (50) are not present. A flat fixture (1) and a notch (20
) having a bonding pattern (60) of the circuit board (6).
) and the leads (50) of the semiconductor chip (5).
) An outer lead bonding apparatus characterized in that the lead (50) and the bonding pattern (60) are collectively connected by the following. 2. The planar fixture (1) has a suction port (10) that sucks the central part of the semiconductor chip (5), and a suction port (10) that is connected to the suction port (10) and that holds the semiconductor chip (5).
The outer lead bonding apparatus according to claim 1, further comprising at least a small diameter suction path (11) disposed so as to be located on a corner of the outer lead bonding device. 3. The outer lead bonding according to claim 1, wherein the planar fixture (1) comprises a clamp mechanism (100) that holds the semiconductor chip (5) at a plurality of corners. Device.