JPH1187470A - Retention transportation device of semiconductor chip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve the retention transportation device of a semiconductor chip for preventing blocking of a pipe and suction force of a suction-retaining tool from decreasing by automatically discharging dust clogged in a pipe and a filter, while the manufacturing facility of a semiconductor is being driven with a relatively simple method. SOLUTION: A first check valve 2 is provided closer to the side of a collet 1 than of a filter 4 of a vacuum pipe 6, a vacuum branch pipe is provided between the filter 4 and the first check valve 2, a second check valve 3 is provided at a side opposite to the vacuum pipe of the branch pipe, and a direction-switching valve 5 for switching at which a vacuum pipe 8 is connected to the vacuum pipe or to an air discharge port 9 is provided a side opposite the collet 1 rasher than the filter 4. Then, the direction-switching valve 5 is connected to the vacuum port 8, the first check valve 2 is opened, the second check valve 3 is closed, a semiconductor chip 10 is sucked and retained by the collet 1, the direction-switching valve 5 is connected to the air discharge port 9, the first check valve 2 is closed, and the second check valve 3 is opened, thus eliminating dust that is clogged in the filter 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor chip holding and conveying apparatus, and more particularly to a semiconductor chip holding and conveying apparatus used in a die bonding step of joining a semiconductor chip to a lead frame or the like in a semiconductor device manufacturing process.

[0002]

2. Description of the Related Art Each semiconductor chip cut from a wafer in a dicing process and set on a dicing tape is transferred and fixed to a package material such as a lead frame prior to wiring by wire bonding. Is called die bonding. What is important in this die bonding process is to fix the chip with sufficient strength to withstand the subsequent processes, and to release heat from the chip by providing appropriate thermal and electrical conductivity. To have electrical conductivity so as not to be electrically charged.

There are three types of die bonding methods: eutectic bonding, solder bonding, and resin bonding. The chart of FIG. 2 shows the features of these various die bonding methods.

In the eutectic bonding method, Au and Si have a eutectic temperature of 37.
The bonding is performed by making an alloy at 0 ° C., and the silicon surface of the chip and the Au plating surface of the substrate are heat-pressed directly or via a preform (foil or the like) of Au-Si or the like. According to this method, a very strong bond can be obtained. However, when the chip size is large, when a package having a different thermal expansion coefficient from silicon is used, the stress applied to the chip is rather increased, and the chip crack is generated. May be caused. In addition, A
The use of u also has the disadvantage of increasing running costs.

In the solder joining method, a Pb-Sn preform (such as a foil) is used, and is joined by heating and melting in an inert gas atmosphere. This method has good thermal conductivity and is easy to absorb stress due to soft bonding, and is effective for bonding a chip generating a large amount of heat to a Cu-based package.

In the resin bonding method, a chip and a substrate are bonded at room temperature using an epoxy-based or polyimide-based thermosetting resin, followed by heating and curing.

In the eutectic bonding method and the solder bonding method, it is necessary to perform the bonding in an inert gas such as a high-temperature nitrogen gas in order to prevent oxidation which causes the generation of bubbles (voids). In addition, there is a problem in that the cost is high in terms of material and process. In this regard, the resin joining method can be operated at room temperature without using an inert gas and is inexpensive in material, so it is inferior in heat resistance and heat conductivity, and may be contaminated by an adhesive, but it has become the current mainstream. ing.

FIG. 3 shows a basic configuration of a die bonding apparatus using a resin bonding method. The die bonding apparatus includes a bonding head section 21, a chip supply section 22, a lead frame supply section 23, a lead frame transport section 24, a lead frame storage section 25 after die bonding, and a paste (resin) supply section 26.

Here, the bonding head unit 21 picks up a semiconductor chip placed on the dicing tape in the wafer cassette ring 221 by a suction holder called a collet 223, and presses after positioning by a chip gauging 222. The device 211 has a function of bonding to the chip by pressing. That is, collet 2
Reference numeral 23 has a function of holding the semiconductor chip by vacuum suction, transferring the semiconductor chip to a lead frame or the like, and mounting it.

FIG. 4 shows a shape diagram (a) of an example of such a collet 223 and an enlarged view (b) of its tip.
In this example, the chip suction surface of the collet 223 is concave,
It has a taper on four sides and a vacuum suction port in the center.
With such a structure, the chip can be held in contact with the side of the chip without contacting the circuit surface on the surface of the chip.

On the other hand, the lead frame is supplied from the loading unit 231 of the lead frame supply section 23,
After the chips are bonded in the above-described die bonding step, the chips are stored in the magazine 251 of the lead frame storage unit 25.

By the way, dust such as silicon dust generated when the semiconductor chip is cut in the dicing process may adhere to the semiconductor chip. For example, in diamond brave dicing, pure water is used as a grinding fluid. If the specific resistance of the grinding fluid is high, the ground silicon dust tends to be charged with static electricity.

When the semiconductor chip is vacuum-adsorbed by the collet 223, dust such as silicon dust may be generated from the semiconductor chip and may enter the inside of the vacuum pipe connected to the collet 223. If such dust or the like enters the inside of the vacuum pipe, the vacuum pipe may be clogged and cause a failure in the apparatus, or the suction force of the collet 223 may be reduced.

Usually, in order to avoid this, a method such as providing a filter for removing dust in the vacuum pipe is adopted.
For example, even if a filter is provided, it is not possible to completely prevent clogging of a pipe, and the adsorbing force of the collet may be reduced due to clogging of the filter. Further, once clogging occurs, it is necessary to replace the filter and remove dust from the vacuum pipe. Such an operation of replacing the filter and removing the dust is not an easy operation, and therefore, it is necessary to stop the equipment for a long time, which causes a decrease in productivity.

[0015]

As described above, in the conventional die bonding process in the semiconductor device manufacturing process, when the semiconductor chip is held by the vacuum suction holder, the dust of the semiconductor chip enters the inside of the vacuum pipe. As a result, there is a possibility that the vacuum pipe may be clogged and a problem such as a decrease in the suction force of the suction holder may occur. In order to prevent this, even if a filter is provided in the vacuum pipe, there is a problem that it takes time and effort to clean and replace this filter, thereby reducing productivity.

According to the present invention, dust accumulated in a pipe or a filter is automatically discharged while a semiconductor manufacturing facility is being driven by a relatively simple method, thereby preventing clogging of a pipe and a decrease in suction force of a suction holder. It is an object of the present invention to realize a semiconductor chip holding / transporting device capable of preventing occurrence.

[0017]

To achieve the above object, the present invention provides a vacuum source, vacuum piping connected to the vacuum source, and vacuum suction of a semiconductor chip connected to the vacuum piping. In a semiconductor chip holding / transporting device comprising a suction holding means for holding and a filter means for removing dust provided in the vacuum pipe means, the vacuum pipe means is closer to the suction holding means than the filter means. First check valve means provided, branch pipe means provided between the filter means and the first check valve means in the vacuum pipe means, and opposite of the branch pipe means to the vacuum pipe means Second check valve means provided on the side, an air blowing source, and the suction holding means are provided on the opposite side of the filter means in the vacuum pipe means,
Directional switching valve means for switching between connecting the vacuum piping means to the vacuum source or connecting to the air blowing source, connecting the directional switching valve means to the vacuum source side, the first check The valve means is opened, the second check valve means is closed, the semiconductor chip is sucked and held by the suction holding means, the direction switching valve means is connected to the air blowing source side, and the first check valve means is opened. The method is characterized in that the second check valve means is closed and the dust accumulated in the filter means is removed by opening the second check valve means.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a semiconductor chip holding and conveying device according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram showing a configuration of a semiconductor chip holding and conveying device according to one embodiment of the present invention. In FIG. 1, 1
Is a collet as suction holding means, 2 is a check valve, 3
Is a check valve, 4 is a dust filter, 5 is a direction switching valve,
6 is a pipe, 7 is an outlet, 8 is a vacuum port connected to a vacuum source,
Reference numeral 9 denotes an air outlet connected to an air blowing source, 10 denotes a semiconductor chip, 11 denotes a dicing tape, and 12 denotes a lead frame or the like. The directional control valve 5 has a function of connecting the pipe 6 to the vacuum port 8 or the outlet 9 by switching.

In the vacuum suction device, in a normal suction mode, the direction switching valve 5 is switched to the vacuum port 8 side, the check valve 2 is opened, and the pipe 6-6 branched from the dust filter 4 is opened.
The check valve 3 provided in 1 is closed. Then, the pipe 6 becomes a vacuum pipe, and the collet 1 becomes the semiconductor chip 10.
Can be adsorbed. At this time, the dust contained in the intake air is captured by the dust filter 4. In this state, the semiconductor chip 10 is picked up from the dicing tape 11 using the collet 1 and
And die-bonding work is performed by bonding with a resin paste or the like.

When the die bonding operation is completed, the direction switching valve 5 is switched to the outlet 9 side, the check valve 3 is opened, and the check valve 2 is closed to set a dust discharging mode. Then, the pipe 6 behind the check valve 2 becomes a discharge pipe,
Dust and the like that have adhered to the semiconductor chip 10 in the previous suction mode and accumulated in the dust filter 4 are discharged and discharged to the outside through the discharge port 7. As a result, dust and the like are discharged after being caught by the dust filter 4, and there is no possibility that dust or the like may enter the inside of the pipe 6 on the vacuum port side from the dust filter 4, and the collet 1 always maintains a constant suction force. be able to.

Further, the operation of removing dust adhering to the semiconductor chip 10 in advance can be eliminated. Further, the dust accumulated in the dust filter 4 is discharged each time, so that the dust filter 4 does not need to be replaced.
Since the step of discharging the dust accumulated in the dust filter 4 can be executed in a short time between the steps of picking up the semiconductor chip 10 using the collet 1, the takt time becomes longer as a whole. There is no.

In the above description, the switching of the directional control valve 5 and the opening and closing of the check valve 2 and the check valve 3 have been described independently. The opening and closing of the check valve 3 can be easily realized. In this case, dust can be automatically removed without performing a special operation, and workability can be further improved and efficiency can be improved.

[0023]

As described above, according to the first aspect of the present invention, a vacuum source, a vacuum pipe connected to the vacuum source, and a semiconductor chip connected to the vacuum pipe and held by vacuum suction. In a semiconductor chip holding / transporting device provided with a collet and a dust removing filter provided in a vacuum pipe, a first check valve provided on a collet side of a vacuum pipe filter, a filter and a first filter. A branch pipe provided between the check valves, a second check valve provided on the side of the branch pipe opposite to the vacuum pipe, an air blow source, and a vacuum pipe provided on the opposite side of the collet with respect to the filter. A directional control valve for switching between connection to a source and connection to an air blowing source, connecting the directional control valve to the vacuum source side, opening a first check valve, closing a second check valve, and forming a collet. Yo Performs suction holding of the semiconductor chip,
The directional control valve is connected to the air blowing source side, the first check valve is closed, and the second check valve is opened to remove dust accumulated in the filter. By doing so, there is no possibility that dust or the like may enter the inside of the pipe on the vacuum source side from the filter, and the filter can be automatically cleaned between the suction and transfer operations of the semiconductor chip.
Thereby, the collet can always maintain a constant suction force. Therefore, the operation of removing the dust adhering to the semiconductor chip in advance can be made unnecessary, and the operation of replacing the dust filter becomes unnecessary. Furthermore, the tact time does not increase. Therefore, it is possible to solve the problem that productivity is reduced due to cleaning or replacement.

According to a second aspect of the present invention, the switching of the directional control valve and the opening and closing of the first check valve and the second check valve are performed in conjunction with each other. Thereby, dust can be efficiently removed and workability can be further improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a semiconductor chip holding and conveying device according to an embodiment of the present invention.

FIG. 2 is a table showing characteristics of various die bonding methods.

FIG. 3 is a configuration diagram showing a basic configuration of a die bonding apparatus using a resin bonding method in which the present invention is used.

FIG. 4 is a diagram showing a shape of a collet used in a semiconductor chip holding and conveying device and an enlarged view of a tip.

[Explanation of symbols]

1 ... collet, 2 ... check valve, 3 ... check valve,
4 ... Dust filter, 5 ... Direction switching valve, 6 ... Piping, 7 ... Exhaust port, 8 ... Vacuum port, 9 ... Outlet, 10 ... Semiconductor chip,
11: dicing tape, 12: lead frame, 21
... bonding head part, 22 ... chip supply part, 23 ...
Lead frame supply unit, 24 ... lead frame transport unit,
25: Lead frame storage section, 26: Paste supply section,
211 ... Pressurizing device, 221 ... Wafer cassette ring,
222: tip gauging, 223: collet, 224
… Camera, 231 loading unit, 251 magazine, 261 paste dispenser.

Claims (2)

[Claims] 1. A vacuum source, vacuum piping means connected to the vacuum source, suction holding means connected to the vacuum piping means for vacuum-suctioning and holding a semiconductor chip, and provided in the vacuum piping means. A semiconductor chip holding / transporting device provided with a dust removing filter means, a first check valve means provided closer to the suction holding means than the filter means of the vacuum pipe means, A branch pipe means provided between the filter means and the first check valve means, a second check valve means provided on a side of the branch pipe means opposite to the vacuum pipe means, and an air blowing source. Provided on the opposite side of the suction and holding means from the filter means in the vacuum piping means, and connecting the vacuum piping means to the vacuum source or connecting to the air blowing source. Directional switching valve means for switching whether to perform the operation, connecting the directional switching valve means to the vacuum source side, opening the first check valve means, closing the second check valve means, and holding the suction holding means The direction switching valve means is connected to the air blowing source side, and the first
Wherein the check valve means is closed, and the second check valve means is opened to remove dust accumulated in the filter means. 2. The apparatus according to claim 1, further comprising control means for interlocking the switching of said direction switching valve means and the opening and closing of said first check valve means and said second check valve means. A semiconductor chip holding and conveying device according to claim 1.