KR100577549B1 - Chemical mechanical polishing equipment - Google Patents

Abstract

In order to separate the first area and the second area where the chemical mechanical polishing facilities are installed, the turnover function of the wafer is substituted for the robot, and a robot capable of turning over the wafer is installed in each of the first and second areas. do.

Thus, the chemical mechanical polishing of any one of the chemical mechanical polishing facilities installed in the first and second regions is unnecessary because the respective chemical mechanical polishing facilities installed in the first and second regions do not need to share the wafer turnover device. If a plant fails, the other chemical mechanical polishing plant can be made available, increasing plant uptime.

In addition, regardless of the robot that loads and unloads the wafer, the chemical mechanical polishing facility installed in the first region and the chemical mechanical polishing facility installed in the second region undergo a wafer polishing process independently of each other, thereby loading and unloading the wafer. Reduced loading time can improve product productivity.

Description

Chemical mechanical polishing equipment

1 is a block diagram showing a conventional chemical mechanical polishing facility,

Figure 2 is an explanatory diagram for explaining the progress of the conventional chemical mechanical polishing.

3 is a block diagram showing a chemical mechanical polishing facility according to the present invention,

4 is a perspective view schematically showing a chemical mechanical polishing facility according to the present invention,

5 is a perspective view showing a wafer turn-over robot according to the present invention;

6 is an explanatory diagram for explaining the progress of chemical mechanical polishing according to the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to chemical mechanical polishing, and more particularly to unloading wafers loaded into a wafer cassette and a polisher to turn over the front and rear surfaces of the wafer, and from the wafer cassette to the poly A chemical mechanical polishing facility having a wafer turn-over robot that travels reciprocally up to shredder.

BACKGROUND ART In general, semiconductor chips are a collection of semiconductor devices manufactured by a semiconductor process. Recently, the development of VLSI, a large-scale semiconductor chip having high semiconductor device density per unit area and fast operation speed, has reached a considerable level.

In recent years, as VLSI has become more highly integrated, a multilayer structure in which a semiconductor device is formed over multiple layers, an interlayer insulating film (BPSG) is formed between layers, and the interlayer wirings are interconnected by via holes have become common. However, when the semiconductor chip is formed by the multilayer structure, there is no problem in the lower layer thin film. However, as the upper layer becomes deeper, the unevenness of the lower thin film is intensified. There is a problem that distortion occurs.

In order to overcome the difficulties in performing the semiconductor process due to the distortion of the semiconductor thin film, a method of mechanically polishing a part of the semiconductor thin film, for example, an interlayer insulating film belonging to a thick layer, has been performed. The so-called chemical mechanical polishing method has been developed that is then polished by a mechanical method.

In order to chemically and mechanically polish the interlayer insulating film, an abrasive called a slurry is required. The slurry is a mixture of abrasive particles such as alumina and silica and a pH adjusting liquid, and the surface of the interlayer insulating film is chemically polished after chemical treatment. Play a role.

As shown in FIG. 1, the chemical mechanical polishing facility 1 is mainly a wafer cassette loader 10 installed at one end of a bay, a polisher 20 installed at the other end of the bay, and a wafer cassette loader 10. ) And a wafer turnover device 50 disposed between the polisher 20 and the polisher 20 to flip the wafer, a slurry removal device 30 provided between the polisher 20 and the wafer turnover device 50, and a wafer cassette loader ( 10) and a wafer cleaning device 40 provided between the wafer turn-over device 50 and a plurality of robot arms 60 and 70 for transferring the wafer.

In detail, a wafer cassette on which wafers to be processed are loaded is mounted on the wafer cassette loader 10 installed at one end of the bay, and the first and second wafer cassette loaders 10 and 12 are installed. Divided.

In addition, first and second wafer cleaners 42 and 44 are installed in the vicinity of the first and second wafer cassette loaders 12 and 14, and the first and second wafer cleaners 42 and 44 are It consists of a cleaning liquid supply nozzle which supplies a cleaning liquid, and a spin dryer which dries a wafer.

Also, adjacent to the first and second wafer cleaners 42 and 44, first and second wafer turn-over devices 52 and 54 which serve to flip the wafer are provided. 52 only turns over wafers free of slurry, pure water, and the like, and the remaining second wafer turn-over device 54 turns over only wafers containing slurry, pure water, and the like.

In addition, first and second slurry removal devices 32 and 34 are installed in the vicinity of the first and second wafer turn-over devices 52 and 54, and the first and second slurry removal devices 32 and 34 are provided. The rollers for slurry removal contacting each other at a predetermined pressure are provided.

Adjacent to the first and second slurry removal devices 32 and 34, the first and second polishers 22 and 24 are installed. The first and second polishers 22 and 24 are used to remove the polishing pad and the wafer. It consists of the wafer chuck which adsorbs and fixes, and the slurry supply part which supplies a slurry.

Here, the first wafer cassette loader 12, the first wafer cleaner 42, the first wafer turn-over device 52, the first slurry remover 32, and the first polishers 22 face each other. The second wafer cassette loader 14, the second wafer cleaning device 44, the second wafer turn over device 54, the second slurry removing device 34 and the second polisher 24 are installed at the viewing position. .

Further, the first and second robots 60 and 70 are disposed between the first wafer cleaner 42, the second wafer cleaner 44, and the first slurry remover 32 and the second slurry remover 34. The first robot 60 linearly reciprocates from the wafer cassette loader 10 to the wafer turn over device 50, and the second robot 70 moves from the wafer turn over 50 to the polisher 20. Linear reciprocating motion up to).

In addition, two robot arms (not shown) are installed in each of the first and second robots 60 and 70, and one robot arm of the two robot arms is dried after the wafer to be processed and the wafer cleaning are completed. It is a dry arm for transporting wafers, and the other robot arm is a wet arm for transporting wafers wet with slurry and pure water.

The polishing sequence by the conventional chemical mechanical polishing facility configured as described above will be described with reference to FIG. 2.

First, the dry arm of the first robot unloads one wafer from the wafer cassette placed in the first wafer cassette loader 12 and then moves to the first wafer turn-over device 52, and then the first wafer turn-over device ( 52) to load the wafer.

Subsequently, when the wafer is turned over by the first wafer turn-over device 52, the dry arm of the second robot moves to the first polisher 22 while unloading the turned-over wafer, and then the first polisher. (22).

After the wafer polished for a predetermined time by the first polisher 22 is transferred to the first slurry removing device 32 by the wet arm of the second robot 70, the slurry on the wafer is first removed. And the wet arm of the second robot 70 is transferred to the second wafer turn over device 54.

When the wafer loaded in the second wafer turn-over device 54 is turned over, the wet arm of the first robot 60 unloads the turned-over wafer and transfers it to the first wafer cleaner 42.

Here, the first wafer cleaning device 42 cleans the loaded wafer to completely remove the slurry remaining on the wafer surface, and then dry the cleaning liquid.

The wafer thus cleaned is loaded back into the first wafer cassette 12 by the dry arm of the first robot 60.

The wafer unloaded from the second wafer cassette 14 is also subjected to chemical mechanical polishing in the same order as the method described above.

However, when the chemical mechanical polishing of the wafer proceeds as described above, the first wafer turn-over device 52 and the first and second wafers turn over only the unloaded wafers from the first and second wafer cassettes 12 and 14. Since the second wafer turn-over device 54 which turns over only the unloaded wafers from the two polishers 32 and 34 is shared, the first wafer turn-over device 52 or the second wafer turn-over device ( When 54) fails or replaces, the entire chemical mechanical polishing facility cannot be used, resulting in a decrease in productivity.

In addition, since the first and second polishers share the first and second robots in common, the time for loading or unloading the wafer into the first and second polishers becomes longer.

This means waiting for the wafer to be unloaded in the other wafer cassette while the first robot unloads the wafer from one of the first and second wafer cassettes and transfers it to the first wafer turnover, and the second This is because the wafer loaded in the other polisher has to wait for the unloaded while the robot takes the wafer out of the polisher of either the first or second polisher and transfers it to the second wafer turnover.

Accordingly, an object of the present invention has been made in view of the above problems, and the wafer is circulated to each robot which circulates and transfers the unloaded wafer from each wafer cassette to a polisher-slurry removal device-wafer cleaning device-wafer cassette. By providing the turnover function, the chemical mechanical polishing process can be performed without a separate wafer turnover device, thereby maximizing the operation efficiency of the chemical mechanical polishing facility.

Other objects of the present invention will become more apparent from the following detailed description and the accompanying drawings.

In order to achieve the object of the present invention, the present invention provides a wafer turn-over robot having a function of turning over a wafer between a wafer cassette loader and a polisher facing each other.

For example, the wafer turn-over robot includes a transfer rail, a robot body installed on the transfer rail, a rotating body which is raised and lowered with respect to the robot body and rotated in a predetermined direction, and two robots which are horizontally installed with respect to the rotating body. The robot arm is composed of arms, the turn over rods fixed to the motor installed in the rotating body to rotate in a predetermined direction, the cylinder rods installed at the end of the turn over rods and the linear reciprocating motion by the cylinder, the cylinder rod It is composed of adsorption blades which are fixed to the field and vacuum adsorb the wafer.

Preferably, the gap between the wafer cleaner and the slurry removal apparatus is spaced at least wider than the diameter of the wafer to form a wafer turnover space between the wafer cleaner and the slurry removal apparatus.

Hereinafter, the configuration and operation of the chemical mechanical polishing facility according to the present invention will be described in more detail with reference to FIGS. 3 to 6.

As shown in FIG. 3, the chemical mechanical polishing facility 100 installed in the bay is largely equipped with a wafer cassette loader 110, a wafer cleaning device 140, a slurry removal device 130, and a polisher on which a wafer cassette 15 is seated. Wafer turn-over robot that serves to turn over the unloaded wafer from the wafer cassette 110 and the wafer cassette 110 to the polisher 120 and then load the wafer which has been polished back into the wafer cassette 110 ( 160,170).

Here, the bay is divided into first and second regions 102 and 104, and each of the first and second regions 102 and 104 is a wafer cassette loader 110, a wafer cleaner 140, a slurry remover 130, and a poly A chemical mechanical polishing facility consisting of a shimmer 120 and wafer turnover robots 160 and 170 is installed.

The first region 102 has a first wafer cassette loader 112, a first wafer cleaner 142, a first slurry remover 132, a first polisher 122, and a first wafer turn over robot 160. ), A second wafer cassette loader 114, a second wafer cleaner 144, a second slurry remover 134, a second polisher 124, and a second wafer in the second region 104. The turn over robot 170 is installed.

Since the arrangement and configuration of each component installed in the first region are the same as the arrangement and configuration of each component installed in the second region, only the components installed in the first region will be described below.

The first wafer cassette loader 112 is installed at one end of the first region 102, the first polisher 122 is installed at the other end of the first region 102, and the first wafer cassette loader 112 is provided. ) Are placed on the wafer cassettes 115 on which the wafers 115a to be polished are loaded.

In addition, the first wafer cleaning apparatus 142 is installed adjacent to the first wafer cassette loader 112, and the first slurry removing apparatus 132 is provided at a predetermined interval from the first wafer cleaning apparatus 142.

Preferably, the gap between the first wafer cleaner 142 and the first slurry removal device 132 is spaced at least greater than the diameter of the wafer 115a to form the first wafer turn over space 182. This is not only a space for turning over the wet wafer 115a but also a space for rotating the wafer 115a in the first region 102 having a narrow space.

As in the first region 102, in the second region 104, the second gap between the second wafer cleaner 144 and the first slurry removal apparatus 134 is spaced apart at least larger than the diameter of the wafer 115a so that the second region 104 is spaced apart from the second region 104. The wafer turn over space portion 184 is formed.

Meanwhile, according to the present invention, the first wafer turn over robot 160 is disposed between the first wafer cleaner 142, the first wafer turn over space 182, and the first slurry remover 132 arranged in a line. The first wafer turn over robot 160 is moved along the transfer rail 162 so as to be reciprocated.

Thus, the structure of the 1st polisher 122 installed in the 1st area | region, the 1st slurry removal apparatus 142, the 1st wafer cleaning apparatus 132,134, and the 1st, 2nd wafer turn-over robots 160 and 170 is attached. Referring to Figure 4 in more detail as follows.

The first polisher 122 is installed to face the polishing pad 122a and is spaced apart from the upper surface of the polishing pad 122a by a round-shaped polishing pad 122a for grinding the entire surface of the wafer 115a. And a wafer chuck 122b for vacuum suctioning the wafer 115a placed on the upper surface of the polishing pad 122a, and a slurry supply device 122c for spraying the slurry on the polishing pad 122a.

Here, either or both of the polishing pad 122a and the wafer chuck 122b are configured to be rotatable in a predetermined direction.

In addition, the slurry removal device 132 is installed so that the two slurry removal rollers 132a face each other vertically at a predetermined interval to remove the slurry on the wafer 115a, the slurry removal rollers 132a mutually The slurry is removed when the wafer 115a passes through the slurry removal rollers 132a and 134a in contact with a predetermined pressure.

On the other hand, the first wafer cleaning apparatus 142 provided adjacent to the first wafer cassette loader 112 remains in the cleaning liquid supply nozzle 142b and the wafer 115a for washing away the slurry remaining on the wafer 115a. It consists of the spin dryer 142a for drying the wash liquid which exists.

As described above, the first wafer turn over robot 160 according to the present invention is installed from the first polisher 122 to the first wafer cassette loader 112, and the first wafer turn over robot 160 is installed. A moving rail 162 to be moved, a robot body 164, a rotating body 166 installed on the robot body 164 to move up and down in a horizontal direction by a cylinder, and to rotate in a predetermined direction by a motor, and to rotate It is composed of two robot arms 167 and 168 installed on the body 166 and horizontally contracted and relaxed with respect to the rotation bodies 166 and 176 by a cylinder, and rotated in a predetermined direction by a motor.

More specifically, referring to FIG. 5, each of the robot arms 167 and 168 is fixed to a motor (not shown) installed in the pivoting body 166 to rotate in the rotational direction of the motor 167a and 168a. And the cylinder rods 167b and 168b installed at the ends of the turn over rods 167a and 168a and linearly reciprocating by a cylinder (not shown), and the end portions of the cylinder rods 167b and 168b and the wafer 115a. ) Is composed of adsorption blades 167c and 168c for vacuum adsorption.

One of the two robot arms 167 and 168 configured as described above is a wet arm 167 which suction-transfers the wafer 115a soaked with slurry or cleaning liquid, and the other is a dried wafer 115a. It is a dry arm 168 that carries suction.

Referring to the accompanying drawings, the operation of the chemical mechanical polishing facility according to the present invention configured as described above is as follows.

First, the suction blade 168b of the dry arm 168 installed in the first wafer turn over robot 160 vacuums a single wafer 115a from the wafer cassette 115 placed on the first wafer cassette loader 112. After adsorption, the wafer is transferred to the first wafer turn-over space 182.

Subsequently, after the rotation body 166 rotates about 90 °, when the rotation shaft of the motor installed on the side of the rotation body 166 rotates 180 °, the turn over rod 168a of the dry arm 168 also rotates 180 ° with the rotation shaft. By rotating, the front and rear surfaces of the wafer 115a are turned over.

As described above, the first wafer turn over robot 160 is transferred to the first polisher 122 by the robot transfer rail 162 while the front and rear surfaces of the wafer 115a are turned over. It is placed on the polishing pad 122a.

Subsequently, the wafer chuck 122b sucks and fixes the back surface of the wafer 115a placed on the polishing pad 122a, and supplies the slurry from the slurry supply device 122c, and then the polishing pad 122a or the wafer chuck. 122b rotates to polish the entire surface of the wafer 115a for a predetermined time.

Subsequently, when the chemical mechanical polishing of the wafer 115a is completed, the wafer 115a is separated from the wafer chuck 122b and the wafer 115a on which the slurry is buried is removed. The adsorption blade 167c of the arm 167 is vacuum adsorbed and transferred to the slurry removal device 132.

After the wafer 115a introduced into the slurry removal device 132 flows in between the slurry removal rollers 132a, the slurry on the wafer 115a is removed by the slurry removal roller 132a.

Subsequently, the wafer 115a from which the slurry has been removed is returned to ?? After vacuum adsorption on the adsorption blade 167c of the arm 167, it is transferred to the first wafer turn over space 182, and the front and rear surfaces of the wafer 115a are moved from the first wafer turn over space 182. Turn over again.

As a result, the front surface of the wafer 115a is transferred to the first wafer cleaner 142 in the same state as when the wafer 115a was unloaded from the first wafer cassette 112.

Subsequently, the wafer 115a loaded in the first wafer cleaner 142 is removed from the slurry by the cleaning liquid injected from the cleaning liquid injection nozzle 142b, and then the surface of the wafer 115a is formed by the spin dryer 142a. The washed liquid dries.

Subsequently, after the slurry removal and the slurry cleaning are completed, the wafer 115a is vacuum-adsorbed to the vacuum adsorption blade 168c installed in the dry arm 168 of the first wafer turn-over robot 160 and then loaded again into the wafer cassette 115. do.

In the second region 104, the wafer is chemically polished and reloaded into the wafer cassette through the above-described process. Thus, a series of processes performed in the first region 102 are performed in the second region 104 in the same manner. Since it is performed independently from each other by the description of the chemical mechanical polishing process in the second region 104 will be omitted.

In this way, by installing a wafer turn-over robot capable of turning over the wafer in the first region and the second region, the chemical mechanical polishing process of the wafer is performed in the second region separately from the chemical mechanical polishing process of the wafer in the first region. Increases facility utilization by allowing progress.

As described above, the present invention substitutes the robot with the turnover function of the wafer to separate the first region 102 and the second region 104 in which the chemical mechanical polishing facility is installed, and thus the wafer can be turned over. One robot is installed in each of the first and second regions 102 and 104.

Therefore, the respective chemical mechanical polishing facilities installed in the first region 102 and the second region 104 do not need to share and use the wafer turn-over apparatus, so that the first and second regions 102 and 104 are not used. Even if a failure occurs in any one of the chemical mechanical polishing facilities installed, the other chemical mechanical polishing facility can be used to increase the uptime of the installation.

In addition, the chemical mechanical polishing facility installed in the first region 102 and the chemical mechanical polishing facility installed in the second region 104 independently process the wafer polishing process regardless of the robot for loading and unloading the wafer. In addition, the wafer loading and unloading time is reduced, the product productivity can be improved.

Claims (3)

A wafer cassette loader on which a wafer cassette loaded with wafers to be processed is placed; A wafer cleaning device installed adjacent to the wafer cassette to clean and dry the wafer having completed the process; A slurry removal device installed adjacent to the wafer cleaning device to remove the slurry on the wafer on which the process is completed; A polisher installed adjacent to the slurry removing device and installed on a side opposite to the wafer cassette loader to perform a chemical mechanical polishing process of the wafer; A wafer cassette, the polisher, the slurry remover, and the wafer cleaning, which are installed between the wafer cassette loader and the polisher to turn over the wafer and reciprocate from the wafer cassette loader to the polisher. A wafer turn over robot for transferring the wafer to any of the devices; A chemical mechanical polishing facility comprising a polishing facility consisting of the first region and the second region the same, each process is performed independently. The wafer turn-over robot of claim 1, wherein the wafer turn-over robots of the first and second regions are movably installed from the wafer cassette loader to the polisher, and the transfer rail guides the wafer turn-over robot. A robot body mounted on a rail and moving along the transfer rail, a rotating body vertically raised and lowered with respect to the robot body and rotating in a predetermined direction, and two robot arms horizontally mounted with respect to the rotating body; Include, The robot arm is Turn over rods fixed to a motor installed in the rotation body to rotate in a predetermined direction; Cylinder rods installed at the ends of the turn over rods and performing linear reciprocating motion by a cylinder; And mechanically abrasive blades fixed to said cylinder rods for vacuum suction of said wafer. The wafer turnover space is further formed between the wafer cleaner and the slurry removal apparatus by separating the gap between the wafer cleaner and the slurry removal apparatus at least wider than the diameter of the wafer. Chemical mechanical polishing equipment.

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