JP2753076B2 - Inner lead bonding equipment - Google Patents

Description

The present invention relates to an inner lead bonding apparatus for bonding an electrode of a semiconductor element to an inner lead of a carrier tape.

(Prior Art) A tool used for an inner lead bonder for bonding an electrode of a semiconductor element and an inner lead of a carrier tape in a semiconductor manufacturing process is generally formed of a hard material, and is heated to a high temperature by a cartridge heater or the like. Therefore, the tool is less likely to wear, but rather, due to the high temperature, various foreign substances adhere to the surface during joining. Since the tool is heated to a high temperature (400 to 500 ° C), foreign substances adhering to the surface are easily cured, and have the property of making it difficult to transfer the heat of the tool to the inner leads and semiconductor elements.

As described above, in the inner lead bonder, dirt such as oxide is deposited on the tool surface by repeating bonding. If the bonding is continued without cleaning the tool surface, the thermal conductivity of the tool surface is deteriorated, and the bonding state between the inner lead and the semiconductor element is deteriorated.

Therefore, conventionally, as shown in, for example, JP-A-63-16956, a cleaning table is rotatably supported in the vicinity of a bonding position where inner leads are bonded, and a rotary table is provided on the cleaning table. A grindstone is provided on the upper surface of the turntable. And
After the bonding is repeated several tens of times, for example, the tool surface is joined to the surface of the grindstone, and the tool surface is polished to remove oxides and the like attached to the tool surface.

(Problems to be Solved by the Invention) However, the tool cleaning device for the inner lead bonder configured as described above uses a 400 to 500
Cleaning is performed by pressing the tool surface of the tool held at 0 ° C., rotating the grindstone for about 10 seconds, and moving the tool. Therefore,
During cleaning, there is a problem in that heat of the tool escapes to the grindstone and it takes time for the tool to return to the original temperature (400 to 500 ° C.).

Further, recently, the surface area of the tool has been increased with the increase in the size of the chip, and the degree of the increase is increasing.
For example, if a 13 mm square tool surface is cleaned for 10 seconds, the tool temperature drops from 500 ° C. to 470 ° C. and takes about 16 seconds to recover. Assuming that the tact time of bonding is about 4 seconds, four bondings can be performed during this time, and this loss time is very large.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to prevent the temperature of a tool from dropping during cleaning of a tool surface, to have no waiting time, and to realize an inner lead capable of efficient bonding. An object of the present invention is to provide a bonding apparatus.

[Constitution of the Invention] (Means and Actions for Solving the Problems) In order to achieve the above object, the present invention is a bonding apparatus including a bonding tool and a cleaning mechanism for cleaning a tool surface of the bonding tool. The cleaning mechanism constitutes an inner lead bonding apparatus having a grindstone for cleaning the tool surface, and a heat retaining mechanism for keeping the grindstone at a predetermined temperature. A bonding apparatus having a cleaning mechanism for cleaning a tool surface of the bonding tool, wherein the cleaning mechanism has a grindstone for cleaning the tool surface, and a heat retaining mechanism for keeping the grindstone at a predetermined temperature, A predetermined number of bonds by the bonding tool After Ingu, and it constitutes the inner lead bonding apparatus and performs cleaning of the tool surface by the cleaning mechanism.

Since the tool surface of the tool comes into contact with the grindstone kept at a temperature substantially equal to the temperature of the tool, the heat of the tool does not escape to the grindstone, and the next bonding can be performed without waiting after cleaning.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a cleaning device, and FIG. 3 shows an inner lead bonding device provided with the cleaning device. 3 is a carrier tape shown in FIG.
An inner lead a is provided on this surface. The carrier tape 1 is conveyed in one direction by sprockets 2 and 3, and a bonding portion 4 is provided between the sprockets 2 and 3. This bonding part 4
Is provided with a guide plate 5 for guiding the carrier tape 1, and a part of the guide plate 5 is provided with an opening window 6 for exposing one inner lead a on the carrier tape 1.

Above the guide plate 5, a bonding tool 7 is provided movably in the up-down direction (Z direction) and XY direction, and a mounting table 8 for the semiconductor element b is provided below. Then, the inner lead a on the carrier tape 1 is positioned at a position facing the opening window 6, and the semiconductor element b on the mounting table 8 is positioned on the inner lead a and then stands by on the carrier tape 1. The bonding tool 7 is lowered to bond the inner lead a and the semiconductor element b. That is, the bonding tool 7 is heated to 400 to 500 ° C.
And the semiconductor element b are thermocompression-bonded.

Further, a guide rail 9 is provided below the guide plate 5 located near the bonding portion 4 along the running direction of the carrier tape 1. And
A cleaning device 10 is mounted on the guide rail 9, and the cleaning device 10 can be moved by a cylinder 11.

Referring to FIG. 1, reference numeral 12 denotes a motor as a drive mechanism.
A grindstone holder 14 is provided on the rotating shaft 13. A disc-shaped grindstone 15 is fixed to the grindstone holder 14. Further, the grindstone holder 14 including the grindstone 15 is surrounded by the heater block 16, and the grindstone 15 is disposed inside the heater block 16.
Is designed to rotate. An electric heater 17 as a heat retaining mechanism is embedded in the heater block 16, and the electric heater 17 is connected to a power supply 19 via a control device 18. The heater block 16 is provided with a thermocouple 20, and a temperature detection signal from the thermocouple 20 is input to a control device 18. By controlling the electric heater 17, the temperature of the grindstone 15 is set to the temperature of the bonding tool 7, For example, it is configured to be maintained at 400 to 500 ° C.

Next, the operation of the inner lead bonder cleaning device configured as described above will be described. The electric heater 17 of the cleaning device 10 is always energized, and the heater block 16 is heated. The temperature of the heater block 16 is detected by a thermocouple 20, and this temperature detection signal is
To control the electric heater 17, the grinding wheel 15
Is the temperature of the bonding tool 7, for example, 40 to 500
It is kept at ° C.

On the other hand, the carrier tape 1 of the inner lead bonding apparatus runs one pitch at a time, and
The semiconductor element b on the mounting table 8 is positioned with the inner lead a. Next, when the bonding tool 7 waiting on the carrier tape 1 is lowered, the inner lead a and the semiconductor element b are thermocompression-bonded because the bonding tool 7 is heated to 400 to 500 ° C. When one bonding is completed, the bonding tool 7 is raised, and the mounting table 8 is moved in the horizontal direction and retracts from the opening window 6. Then, when the next inner lead a faces the opening window 6 as the carrier tape 1 runs, bonding is performed by repeating the same operation as described above.

After repeating such bonding several tens of times, the tool surface 7a of the bonding tool 7 (see FIG. 2)
In order to perform cleaning, the cylinder 11 is operated to move the cleaning device 10 along the guide rail 9 to the opening window 6.
Position. Then, when the bonding tool 7 is lowered, the tool surface 7a of the bonding tool 7 is polished by the rotating grindstone 15, and foreign matters and the like adhering to the tool surface 7a are removed. This polishing time is about 10 seconds, but since the grindstone 15 is heated to the same temperature as the bonding tool 7, the temperature of the bonding tool 7 does not drop during the polishing. Then, the next bonding can be performed.

In the embodiment, the cleaning is performed by lowering the bonding tool and contacting the upper surface of the rotating grindstone.However, the bonding tool may be reciprocated in the lateral direction. The cleaning may be performed by reciprocating at a high speed without rotating the grindstone.

[Effects of the Invention] As described above, according to the present invention, since the grindstone for cleaning the tool surface of the tool is kept at a predetermined temperature, the heat of the tool does not escape to the grindstone during cleaning. In addition, the next bonding can be performed without waiting time after cleaning. Accordingly, there is an effect that there is no loss time as in the related art, and efficient bonding is possible.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a cleaning device showing an embodiment of the present invention, FIG. 2 is a side view of the same bonding tool, and FIG. 3 is a perspective view of a bonding device having the same cleaning device. 7 ... Tool, 7a ... Tool surface, 12 ... Motor (drive mechanism), 15 ... Whetstone, 17 ... Electric heater (Heat keeping device).

Claims (2)

(57) [Claims] 1. A bonding apparatus comprising: a bonding tool; and a cleaning mechanism for cleaning a tool surface of the bonding tool, wherein the cleaning mechanism includes a grindstone for cleaning the tool surface, and keeping the grindstone at a predetermined temperature. An inner lead bonding apparatus, comprising: 2. A bonding apparatus comprising: a bonding tool; and a cleaning mechanism for cleaning a tool surface of the bonding tool, wherein the cleaning mechanism includes a grindstone for cleaning the tool surface, and keeping the grindstone at a predetermined temperature. An inner lead bonding apparatus, comprising: a heat retaining mechanism that performs a predetermined number of bondings by the bonding tool, and performs cleaning of the tool surface by the cleaning mechanism.