JP2000317827A - Polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing device that can be applied to the polishing device of drive-in/drive-out method and can raise the processing ability for unit time and unit installation area of the polishing object such as semiconductor wafer and the like. SOLUTION: A polishing device is provided with polishing tables 9, 10, top rings 12, an index table 19, and pushers 17. The plural polishing tables 9, 10 have polishing surfaces. The plural top rings 12 are installed on the corresponding polishing tables 9, 10, hold and press semiconductor wafers on the polishing surfaces. The index table 19 is positioned at prescribed point on the circumference from the center of rotation when the top rings 12 are installed on the attainable positions. It has plural parts to hold polishing objects and also has an indexing function to work out these plural parts. The pushers 17 deliver polishing objects from the index tables 19 to the top ring 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing apparatus for making a surface of an object to be polished such as a semiconductor wafer flat and a mirror surface, and more particularly to an index table (rotary transporter) for supplying the object to be polished.
And a polishing apparatus having the same.

[0002]

2. Description of the Related Art In a semiconductor manufacturing process, polishing is performed to make a wafer surface flat and mirror-like in a semiconductor wafer manufacturing process, and a layer formed on a device is made flat and mirror-finish in a device manufacturing process. Polishing. A polishing apparatus is used in the polishing process in the semiconductor wafer manufacturing process and device manufacturing process. This polishing apparatus is called a chemical mechanical polishing apparatus.

A conventional polishing apparatus is a dedicated polishing apparatus for performing only polishing, and a semiconductor wafer having been subjected to polishing is placed in a movable water tank and transported to a next cleaning step. However, in the method in which the polishing step and the cleaning step are separately performed, the cleanness of the clean room is impaired, and the transfer of the wafer after the polishing has been forced to rely on manual transfer means. Further, since two types of devices, a polishing device and a cleaning device used in a subsequent cleaning process, are required, a large installation space is required.

Therefore, in order to clean the polishing step and reduce the installation space of the apparatus, the polishing step and the cleaning step are performed in the same apparatus, the semiconductor wafer is put into the apparatus in a dry state, and the semiconductor wafer is processed. A polishing apparatus has been developed which realizes a dry-in / dry-out method in which a wafer is discharged from the apparatus in a clean and dry state.

On the other hand, a polishing apparatus for performing only polishing has been improved, so that the cleanness of a clean room can be maintained. Further, the production capacity of the polishing apparatus and a cleaning machine used in a cleaning step after polishing has been increased, and the polishing apparatus and the polishing apparatus in the polishing step have been improved. It has become possible to reduce the number of washing machines and to reduce the installation space equivalent to or larger than that of the dry-in / dry-out type polishing apparatus.

[0006]

However, in the above-described polishing apparatus which performs only polishing, the transport means for transporting the semiconductor wafer after the polishing has been completed.
When relying on manual transfer means, the method of storing the wafers is a mobile water tank when automating the transfer means. Therefore, handling is difficult, and the transfer means has a problem. Further, the conventional dry-in / dry-out type polishing apparatus has a low production capacity per unit time and unit installation area, requires a large number of apparatuses in each polishing step, requires a large installation space, and requires a large installation space. There is a problem that management costs increase.

SUMMARY OF THE INVENTION An object of the present invention is to solve all the problems of the prior art described above and is applicable to the above-mentioned dry-in / dry-out type polishing apparatus. It is an object of the present invention to provide a polishing apparatus capable of improving processing time per unit area and time.

[0008]

According to a first aspect of the present invention, there is provided a polishing apparatus comprising: a plurality of polishing tables each having a polishing surface; a plurality of polishing tables provided corresponding to the plurality of polishing tables; And a plurality of top rings that press the object to be polished against the polishing surface, and are installed at positions where the plurality of top rings can reach, and are located on a predetermined circumference from the rotation center to hold the object to be polished. A transport mechanism having a plurality of parts, and having an index function for indexing the plurality of parts,
A pusher for transferring an object to be polished between the transport mechanism and the top ring is provided.

According to a second aspect of the present invention, there are provided a plurality of polishing tables each having a polishing surface, a plurality of polishing tables provided respectively corresponding to the plurality of polishing tables, holding the object to be polished, and polishing the object to be polished. A plurality of top rings that press against a surface, and a plurality of top rings that are provided corresponding to each of the top rings at positions where the plurality of top rings can reach, and that are located on a predetermined circumference from the rotation center and hold the object to be polished. A plurality of transfer mechanisms having an index function for indexing the plurality of parts, and a pusher for transferring an object to be polished between the transfer mechanism and the top ring. Things.

In a third aspect of the present invention, a plurality of polishing tables each having a polishing surface, a plurality of polishing tables are provided corresponding to the plurality of polishing tables, respectively, and the polishing objects are held and the polishing objects are polished. A plurality of top rings pressed against a surface, and a transport mechanism having an index function of transferring an object to be polished to the top ring. Each of the plurality of top rings is transported to a position above the polishing table. It is movable to a position above the mechanism.

According to a fourth aspect of the present invention, there is provided a polishing table having a polishing surface, a top ring for holding the polishing object and pressing the polishing object against the polishing surface, and a robot for transporting the polishing object in the apparatus. And a position for transferring an object to be polished to the top ring,
A transfer mechanism for transferring the object to be polished to and from a position for transferring the object to be polished to the robot, wherein the transfer mechanism linearly moves between the two positions. Things.

According to a fifth aspect of the present invention, there is provided a polishing table having a polishing surface, a top ring for holding an object to be polished and pressing the object to be polished against the polishing surface, and a top ring between two positions in the apparatus. A transport mechanism for transporting the object to be polished, wherein the transport mechanism comprises at least two pedestals for holding the object to be polished, wherein the at least two pedestals are individually movable at planar positions. It is characterized by being located at different heights.

According to the present invention, it is possible to reduce the time required to transport a polishing target such as a semiconductor wafer to a top ring, and to dramatically increase the number of processed polishing targets per unit time (throughput). be able to. In a preferred aspect of the present invention, the transport mechanism includes a loading table for holding the object to be polished before polishing and an unloading table for holding the object to be polished after polishing. Further, in a preferred aspect of the present invention, each of the top rings is rotated around a rotation axis, and is located at a position above the polishing table and a position above the transport mechanism.

Further, in a preferred aspect of the present invention, a dresser dedicated to each of the polishing tables is provided. Also,
In a preferred aspect of the present invention, the pusher is provided below or on the transport mechanism. In a preferred aspect of the present invention, the distance between the rotation axis of the transport mechanism and the rotation axes of the plurality of top rings is equal.

In a preferred aspect of the present invention, the transport mechanism includes a first table for transporting a polishing object to be polished by one of the plurality of polishing tables, and the plurality of polishing tables. And a second table for transferring a polishing object to be polished by another polishing table. Further, in a preferred aspect of the present invention, each of the first table and the second table mounts a load table on which a polishing target before polishing is mounted and a polishing table after polishing. And an unload table.

In a preferred aspect of the present invention, the transport mechanism moves the object to be polished to a first polishing table and a second polishing table.
Equipped with four tables to supply to the polishing table of
A loading table for a first polishing table, an unload table for a first polishing table, an unload table for a second polishing table, and a second table. A loading table for the polishing table and a loading table are arranged clockwise around the rotation axis of the transport mechanism. In a preferred aspect of the present invention, a pusher for transferring the object to be polished between the transport mechanism and the top ring is disposed below the transport mechanism or on the transport mechanism. Further, in a preferred aspect of the present invention, the transport mechanism includes a loading table for holding the polishing object before polishing, and an unload table for holding the polishing object after polishing.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a polishing apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing an arrangement configuration of each part of the first embodiment of the polishing apparatus according to the present invention. The polishing apparatus shown in FIG. 1 is a wafer cassette 4 for storing a large number of semiconductor wafers.
0 is provided with two rotatable load / unload stages 1. A transfer robot 2 having two hands is arranged at a position on the load / unload stage 1 at which each wafer cassette 40 can be reached.

The upper hand of the two hands in the transfer robot 2 holds only a clean (dry) semiconductor wafer, and the lower hand is dirty (dirty) and wet (wet). ) Grab only the wafer. On both sides of the transfer robot 2, two cleaning machines 3 for cleaning and drying the semiconductor wafer after polishing are arranged. Each washing machine 3 is installed at a position where the hand of the transfer robot 2 can reach. In addition, a reversing machine 4 and a reversing machine 5 for reversing the semiconductor wafer are disposed at a position symmetrical with respect to the load / unload stage 1 and at which the hand of the carrying robot 2 can be reached, with the center 2c of the carrying robot 2 as a base point. I have.

The reversing machine 4 has both a chuck mechanism for chucking the semiconductor wafer and a reversing mechanism for reversing the front and back surfaces of the semiconductor wafer. The reversing machine 4 processes only clean and dry semiconductor wafers. The reversing machine 5 includes a rinsing mechanism for cleaning the semiconductor wafer in addition to the chuck mechanism and the reversing mechanism. The reversing machine 5 processes only dirty and wet semiconductor wafers.

The center 4c of the wafer to be chucked to the reversing machine 5 and the reversing device 4, the line L ₁ connecting the 5c as a reference,
A transfer robot 6 having two hands is disposed at a position symmetrical with the transfer robot 2. Transfer robot 6
Are arranged at positions where the hand of the transfer robot 6 can reach the tables of the reversing machines 4 and 5 and the index table (rotary transporter) 19. Of the two hands of the transfer robot 6, the upper hand grips only the clean and dry semiconductor wafer, and the lower hand grips only the dirty and wet semiconductor wafer.

On both sides of the transfer robot 6, two cleaning machines 7 for cleaning the semiconductor wafer after polishing are arranged. The washing machine 7 is different from the washing machine 3 in the washing method. Each cleaning machine 7 is installed at a position where the hand of the transfer robot 6 can reach. Two transfer robots 8 each having one hand are arranged at positions opposite to the reversing machines 4 and 5 with each washing machine 7 interposed therebetween. Transfer robot 8
Are arranged at positions where the hands of the transfer robot 8 can reach the tables of the washing machines 7 and the index table 19.

The polishing apparatus has a housing 30 surrounding each device, and the inside of the housing 30 is divided into a plurality of rooms (including a polishing room and a cleaning room). The two transfer robots 8 to the load / unload stage 1 are arranged in the cleaning chamber 30A. Then, the transfer robot 8 in the cleaning room 30A
The partition wall 31 is installed at a position adjacent to the partition wall 31.
A polishing room 30B, which is a room different from the cleaning room 30A, is disposed on the opposite side of the polishing room 30B. The polishing chamber 30
B, two polishing tables 9 and 10 and two top rings 12 for holding one semiconductor wafer and polishing while pressing the semiconductor wafer against the polishing tables 9 and 10 are arranged. I have.

FIG. 2 is a view showing the relationship between the top ring 12 and the polishing tables 9 and 10. As shown in FIG.
The top ring 12 is suspended from the top ring arm 11 by a rotatable shaft 32. The top ring arm 11 is supported by a positionable rotation shaft 33, and the top ring 12 is attached to each of the polishing tables 9, 10.
Is accessible to Each top ring 1
Reference numeral 2 denotes an air cylinder provided in the top ring arm 11 so that the semiconductor wafer can be pressed against the polishing tables 9 and 10 with an arbitrary load. Above the central portion of the polishing tables 9 and 10, a polishing liquid nozzle 13 for flowing a polishing liquid for polishing is disposed. A dresser 14 for dressing each of the polishing tables 9 and 10 is provided. Polishing table 9,
A polishing cloth or a grindstone (fixed abrasive) is mounted on the upper surface of 10.

Next, a description will be given of a pusher unit as a transfer device for transferring a semiconductor wafer between the transfer robots 6, 8 and the top ring 12. The pusher part is
Two polishing tables 9, 10 and three transfer robots 6,
It is installed at the center of the space enclosed by 8. There are three types of pusher units, two index table types (rotary transporter type) and one direct acting table type. Next, three types of pusher sections will be described.

1) Index Table Type (Rotary Transporter Type) A FIGS. 3 and 4 show details of the index table type A. FIG. 3 is a plan view, and FIG. 4 is an elevation view. 3 and 4 within the turning range of the top ring 12.
As shown in (1), one pusher 17 as a dedicated wafer transfer mechanism is provided for each of the top rings 12. Each pusher 17 constitutes a dedicated transfer mechanism for transferring the semiconductor wafer to and from the top ring 12.
The pusher 17 has an elevating function, and can move up and down between a wafer transfer position to the top ring 12 and a wafer supply position to transfer a semiconductor wafer to the pusher 17. Between the pusher 17 and the cleaning chamber 30A, an index table (also referred to as a rotary transporter) 19 constituting a transfer mechanism for transferring a semiconductor wafer between the pusher 17 and the transfer robot 6 and the transfer robot 8 is arranged (see FIG. 1). 1, 3 and 4). The index table 19 is rotatable 360 ° in the horizontal direction, and is provided with a positioning mechanism (index mechanism) and tables 15 and 16 for mounting the semiconductor wafer (15 is a table dedicated to loading,
Are placed on a predetermined circumference from the center of rotation at equal intervals, four in total. Note that the tables 15 and 16 do not need to be separated for loading and unloading.

The rotation center of the index table 19 is
As shown in FIG. 1, each table 15, 16 must be arranged at a position such that it can access all of the transfer robot 6, the transfer robot 8 and the top ring 12. In the present embodiment, the rotation tables of the index tables 19 are arranged at positions equidistant from the polishing tables 9 and 10, respectively. Also, the top ring rotating shaft 3
Index table 1 at a position equidistant from 3
Nine rotating shafts are arranged. The index table 19 is provided with a cover 21 so as to be included in the polishing chamber 30B. The cover 21 is formed with a notch large enough to carry a wafer into and out of the index table 19, and a shutter 18 is provided in this notch. Further, a cleaning nozzle 43 for cleaning the wafer, which supplies a cleaning liquid to the wafer, is provided at a wafer transfer position with the robot in the cover 21. At the position of the pusher 17, a cleaning nozzle 42 for supplying a cleaning liquid to the polished top ring 12 for cleaning is provided. The cleaning nozzle 42 for cleaning the top ring 12 can also be used for preventing the top ring 12 from drying during a time when the wafer polishing process is not performed.

2) Index Table Type (Rotary Transporter Type) B FIGS. 5 and 6 are views showing details of the index table type B. FIG. 5 is a plan view and FIG. 6 is an elevation view.
As shown in FIG. 1, between the top ring 12 and the cleaning chamber 30A, an index table (rotary transporter) 19 constituting a transfer mechanism for transferring a wafer between the top ring 12, the transfer robot 6 and the transfer robot 8. Is arranged. The index table 19 is rotatable 360 ° in the horizontal direction and has a positioning mechanism (index mechanism). In the index table 19, pushers 15, 16 of a wafer transfer mechanism for loading and unloading wafers from and to the top ring 12 (15 is a pusher for loading, and 16 is a pusher for unloading).
Are installed at equal intervals on a predetermined circumference from the rotation center. In addition, the pusher does not need to be divided only for loading and unloading.

The pushers 15 and 16 have a lifting function,
Wafer transfer position to top ring 12 and pusher 1
It can be moved up and down between supply positions for transporting wafers to 5,16. As shown in FIG. 1, the rotation center of the index table 19 must be arranged at a position where each pusher 15, 16 can access all of the transfer robot 6, the transfer robot 8, and the top ring 12. The structures of the cover 21, the shutter 18, the cleaning nozzle for cleaning the wafer, and the cleaning nozzle for cleaning the top ring are the same as those of the type A, and thus the description thereof is omitted.

3) Linear motion table type FIGS. 7 and 8 show details of the linear motion table type. FIG. 7 is a plan view and FIG. 8 is an elevation view. Within the turning range of the top ring 12, as shown in FIGS.
One pusher 17 as a dedicated wafer transfer mechanism is provided for each of the top rings 12. The pusher 17 has a lifting function and can move up and down between a wafer transfer position to the top ring 12 and a supply position to transfer the semiconductor wafer to the pusher 17. Two transfer mechanisms 25 for transferring semiconductor wafers between the pusher 17 and the transfer robots 6 and 8 are disposed between the pusher 17 and the cleaning chamber 30A. Each of the two transfer mechanisms 25 includes a table 15 and 16 on which a semiconductor wafer is mounted. Both tables 15 and 16 are located above the pusher 17, and each of the tables 15 and 16 is individually located at a planar position in a linear direction. Can be moved. The table 15 is a table dedicated to loading for transferring the semiconductor wafer to the top ring 12, and
The table 16 is a table dedicated to unloading for receiving a semiconductor wafer from the top ring 12.

The transfer mechanism 25 moves linearly between the top ring 12, the transfer robot 8 arranged in the same row as the pushers 17, and the transfer robot 6 located at the center. Each transport mechanism 25 has two linear rails 26 arranged at different positions in the height direction. Each rail 26 has a table 15 or 16 slidable along the rail.
It has. Two tables 15, 1 of each transport mechanism 25
6 are arranged so as not to interfere with each other in the vertical direction,
It can be individually moved horizontally. Stands 15, 16
Is movable on the rail 26 by a ball screw mechanism and a motor (not shown). With such an arrangement, when the two tables 15 and 16 move, the positions of the two tables 15 and 16 can be replaced in a planar manner. The moving means of the transport mechanism 25 includes a positioning mechanism. Table 1 on which semiconductor wafer is placed
When the wafers 5 and 16 move to the wafer transfer position of the top ring 12, the pusher 17 located below the pusher 17 can push up the semiconductor wafer and transfer the semiconductor wafer to the top ring 12. Conversely, when the pedestals 15 and 16 on which no semiconductor wafer is mounted have moved to the same position, the pusher 17 receives the semiconductor wafer from the top ring and descends to place the semiconductor wafer on the pedestal 1.
5 and 16.

The transfer mechanism 25 is located in the polishing chamber 30B. A notch large enough to load and unload a wafer into and from the transfer mechanism 25 is formed in a partition of the polishing chamber 30B. A shutter 18 is provided. Further, a cleaning nozzle for cleaning the wafer, which supplies a cleaning liquid to the wafer, is provided at a wafer transfer position with the robot in the partition wall. A cleaning nozzle for supplying a cleaning liquid to the polished top ring 12 for cleaning is provided at the position of the pusher 17. The cleaning nozzle for cleaning the top ring 12 can be used for preventing the top ring 12 from drying while the wafer polishing process is not performed.

Next, the overall operation of the polishing apparatus configured as described above will be described. Semiconductor wafers before polishing are stored in a wafer cassette 40,
The cassette 40 is placed on the load / unload stage 1. After all the processing conditions in the apparatus have been input, the apparatus starts automatic operation. In this polishing apparatus, several polishing steps can be performed. In the operation described below, an odd-numbered semiconductor wafer (hereinafter, referred to as a wafer) counted from the upper stage of the wafer cassette is used.
The polishing is sequentially performed on the polishing table 9, and the even-numbered wafers are subjected to the polishing on the polishing table 10. Hereinafter, the polishing step will be described step by step.

In this case, index table type A
The procedure for the pusher section of the index table type B is described in parentheses. Further, for the linear motion table type pusher, the rotation operation of the index table 19 described above is changed to a linear motion, and other operations are the same as those of the index table types A and B.

1. The load / unload stage 1 adjusts the angle, and changes the direction of the wafer cassette 40 until the transfer robot 2 can transfer the wafer. 2. The transfer robot 2 adjusts the angle and height, sucks the wafer in the wafer cassette 40 with a clean hand, and takes out the wafer from the wafer cassette 40.

3. The transfer robot 2 adjusts the angle and height again while holding the wafer, and transfers the wafer to the reversing machine 4. 4. The reversing device 4 chucks the wafer transported by the transport robot 2, and after confirming that the wafer has been normally chucked, rotates the wafer by 180 ° so that the surface to be processed of the wafer faces downward.

5. After confirming that the reversing machine 4 has been normally rotated by 180 °, the transfer robot 6 adjusts the angle and the height, releases the chuck of the reversing machine 4, and receives the wafer from the reversing machine 4 with a clean hand. 6. The transfer robot 6 adjusts the angle and height again, and sets the table 15 (the pusher 1) on the index table 19.
After confirming that there is no wafer in 5), the shutter 18
Is opened, and the wafer is transferred to the placing table 15 (the pusher 15).

7. When it is confirmed that the wafer has been transferred to the placing table 15 (the pusher 15), the index table 19 rotates 90 ° or 270 ° and moves to the wafer transfer position to the top ring 12. 8. The table 15 (the pusher 15) is the top ring 12
When the pusher 17 confirms that the wafer has been moved to a position where the wafer can be accessed, the pusher 17 moves up. (The pusher 15 moves up and chucks the top ring 12). Thereafter, the stage on which the wafer is mounted further rises, and the back surface of the wafer is
2 and the top ring 12 vacuum-adsorbs the wafer at the same time.

9. When it is confirmed that the top ring 12 has normally sucked the wafer, the pusher 17 is lowered, and it is confirmed that the lowering is completed.
Rotates 90 ° or 270 ° in the opposite direction. At this time, the unloading table 16 (pusher 16)
Is located at the wafer transfer position of the top ring 12. Further, simultaneously with the rotation of the index table 19, the rotating shaft supporting the top ring arm 11 rotates, and the top ring 12 moves to the polishing position on the polishing table 9.

10. When it is confirmed that the top ring 12 has moved to the polishing position, the polishing table 9 and the top ring 12 rotate at the speed input in advance in the same direction,
The type and flow rate of the polishing liquid input in advance from the polishing liquid nozzle 13 flow down onto the polishing table 9. Thereafter, the top ring 12 is lowered, and when it is confirmed that the top ring 12 has reached the polishing table 9, a pressing pressure corresponding to the previously input condition is applied to the top ring 12, and the top ring 12 is input in advance. Polishing is performed only for a time.
While the wafer is being polished in these processes, the wafer before the next polishing is also transported in the same procedure, and is transported onto the loading table 15 (the pusher 15).

11. When the polishing is completed, the polishing liquid nozzle 13
Stops the supply of the abrasive liquid, and the top ring 12 vacuum-adsorbs the wafer, and when it is confirmed that the wafer has been adsorbed, the shaft 33 supporting the top ring arm 11 is at a position where the top ring 12 is separated from the polishing table 9 by half. Rotate to come in. 12. When it is confirmed that the top ring 12 has come to a position where it is displaced by half from the polishing table 9, the shaft 33 supporting the top ring arm 11 rotates, and at the same time, the top ring 12 rises and moves above the pusher 17, that is, the top ring To the wafer transfer position. At this time, the index table 19 is stored in step 9 described above.
, The unloading table 16
(Pusher 16) is located at the wafer transfer position of top ring 12.

13. Top ring 12 is pusher 17
(Pusher 16) After confirming that it is located above, pusher 17 (Pusher 16) rises to chuck top ring 12, and at the same time, top ring 12 shuts off the vacuum and blows air or nitrogen and pure water. Then, the wafer is separated on the pusher 17 (the pusher 16). 14． After the top ring 12 has separated the wafer, the pusher 17 descends below the table. (The pusher 16 is lowered to a level at which the transfer robot 8 can transfer a wafer.)

15. Pusher 17 (Pusher 16)
Is lowered and it is confirmed that the wafer is on the table 16 (the pusher 16).
The next wafer before polishing, which has been rotated by 0 ° or 270 ° and has been transferred to the placing table 15 (the pusher 15) in advance, moves to the wafer transfer position of the top ring 12, and is transferred as described above. And polished. At the same time, pure water is sprayed from a rinse nozzle to clean the top ring 12. In addition, pure water is supplied to the wafer to prevent the wafer on the table 16 from drying. Dressing by the dresser 14 is performed after the previous wafer polishing and before the subsequent wafer polishing in order to recover the optimum polishing surface of the polishing table 9 or 10. 16. When the next wafer is conveyed to the top ring 12, the index table 19 is rotated and the table 16 is rotated.
When it is confirmed that the (pusher 16) has moved to a position where the transfer robot 8 can reach, the shutter 18 is opened, the transfer robot 8 adjusts the angle and height, and the wafer is moved from the table 16 (pusher 16). Receive.

17. After the transfer robot 8 receives the wafer from the table 16 (pusher 16), the shutter 1
8 is closed, the transfer robot 8 adjusts the angle and the height, and transfers the wafer to the cleaning machine 7, and at the same time, the cleaning machine 7 chucks the wafer. 18. The cleaning machine 7 confirms that the wafer has been normally chucked, and performs the first-stage cleaning of the wafer after polishing.

19. When the cleaning of the cleaning machine 7 is completed, the transfer robot 6 moves to a position where the cleaning robot 7 can be reached, at the same time adjusts the angle and height, and receives the wafer with a dirty hand. 20. The transfer robot 6 adjusts the angle and height again, and transfers the same to the reversing machine 5, which simultaneously chucks the wafer.

21. After confirming that the reversing machine 5 has chucked the wafer normally, pure water is sprayed from a pure water rinsing nozzle attached to the reversing machine 5 to prevent the wafer from drying, and at the same time, the reversing machine 5 rotates 180 °. With the polished surface of the wafer facing up. 22. After confirming that the reversing device 5 has rotated normally by 180 °, the transfer robot 2 adjusts the angle and height, receives a wafer from the reversing device 5 with a dirty hand, and opens the chuck. I do.

23. The transfer robot 2 adjusts the angle and height again, and transfers the wafer to the cleaning machine 3, and at the same time, the cleaning machine 3 chucks the wafer. 24. The cleaning machine 3 confirms that the wafer has been normally chucked, and performs the second-stage cleaning of the wafer after polishing.

25. After the washing by the washing machine 3 is completed,
The transfer robot 2 adjusts the angle and height, and receives the wafer from the cleaning machine 3 with a clean hand. 26. The transfer robot 2 adjusts the angle and height again,
The polished wafer is transported to the position where the wafer in the wafer cassette was stored before the wafer was processed. 27. The second and subsequent even-numbered wafers are conveyed to the polishing table 10 in the same manner as described above, sequentially polished, cleaned in the same order as described above, and returned to the wafer cassette.

Next, the operation of the index type A pusher will be described in detail with reference to FIGS. 9 and 10. FIG. FIG. 9 is a plan view showing a relationship among a top ring, an index table, a pusher, and a transfer robot.
FIG. 10 is an explanatory diagram of the operation of the pusher. The wafer 102 to be transferred to the top ring 12 is transferred from the direction 210 to the index table 19 by the transfer robot 6 as shown in FIG. The transferred wafer is
The robot hand 160 places the pin 101 on the shoulder of the stepped pin 101 assembled on the index table 19. At this time, the contact portion between the wafer holding portion of the robot hand 160 and the pins 101 and the wafer 102 is different from each other on the outer peripheral portion of the wafer. Thereafter, the index table 19 is rotated by the motor 200 (see FIG. 4), the wafer 102 is moved to the transfer position 215 to the top ring 12, and is located above the pusher 17. FIG. 10A illustrates a state in which the wafer 102 is placed on the index table 19 and transferred above the pusher 17. In this figure, the top ring 12 is located above the index table 19, and the pusher 17 is arranged below the index table 19.

Next, the pusher 17 is raised by the cylinder 105, and the wafer 1 placed on the shoulder of the pin 101 is lifted.
02 is pushed up, and the wafer 102 is placed on the stage 106 of the pusher 17 and changed. At this time, stage 10
6 and wafer 102 are in contact with pins 101 and wafer 1
02 and a part different from the contact part between the robot hand 160 and the wafer 102. FIG. 10B shows the cylinder 10 of the pusher 17.
5 shows a state in which the wafer 102 makes a stroke and the stage 102 of the pusher 17 is in contact with the wafer 102 on the index table 19. At this time, since the alignment guide 107 and the alignment guide 108 of the pusher 17 are in contact with each other, the stage 106 and the stage 109 are at fixed positions.

FIG. 10C shows that the cylinder 105 further strokes and the wafer 102 is moved to the index table 1.
9 lift the stage 109 from the top ring 12
Indicates a state in contact with. When the stage 106 picks up the wafer 102 from the index table 19, since the alignment guide 107 and the alignment guide 108 are not in contact with each other, they can freely move at a planar position. This centering operation can be realized by incorporating a linear guide in the portion A (see FIG. 10A) so as to be orthogonal. The guide 110 of the stage 109 is tapered so that when the guide 110 comes into contact with the top ring 12, the pusher 17 is guided so that the top ring 12 is housed in the guide 110. That is, the pusher 17 has a position adjusting function with respect to the top ring 12. Then, in order to reduce the impact when the stage 109 and the top ring 12 come into contact with each other, the spring 111 and the spring 11
2 is incorporated, and a shock absorber 113 is incorporated so that the contact position can be adjusted.

FIG. 10D shows that the cylinder 114 is further stroked from the state shown in FIG. 10C, the stage 106 on which the wafer 102 is mounted is raised, and the wafer 102 is brought into contact with the suction surface of the top ring 12. Indicates the status. In this state, a spring 11 is used to prevent the stage 106 from pressing the wafer 102 against the top ring 12 more than necessary.
1 and the spring 112 are working. By a series of these operations, the wafer 1 on the index table 19 is
02 is conveyed to the top ring 12.

The top ring 12 and the wafer 102
10 is placed in the index table 19, FIG.
The pusher 17 is operated in the state (c), and the wafer 102 is separated from the top ring 12 in this state. When the wafer 102 is detached from the top ring 12, FIG.
(C) → FIG. 10 (b) → FIG. 10 (a). By operating the pusher 17 in a reverse procedure to a series of operations for sucking the wafer 102 to the top ring 12, the wafer is sucked to the top ring 12. The wafer 102 is transferred onto the index table 19. At this time, the wafer 10
2 is mounted on the pin 101 of the index table 19. After that, the index table 19 is
0, the wafer 102 rotates to the unloading position of the wafer 102, and the wafer 102 is transferred to the robot hand 1 of the transfer robot 8.
By 80, it is carried out in the direction of arrow 211.

FIG. 11 is a plan view showing a modification of the first embodiment of the polishing apparatus according to the present invention. In this embodiment, two loading pushers 15 are arranged on a diagonal line of the index table 19, and two unloading pushers 16 are arranged on a diagonal line of the index table 19. A total of four pushers 15,1
6 are all set on the index table 19.

FIGS. 12 to 16 are schematic process diagrams showing an example of the case where the wafer is polished by the polishing apparatus shown in FIGS. 1 and 11. The wafer is taken out from one wafer cassette (CS1). Each step until the wafer is returned to the wafer cassette (CS1) through the polishing step and the cleaning step, and until the wafer is taken out from the other wafer cassette (CS2) and returned to the wafer cassette (CS2) through the polishing and cleaning steps. 3 are illustrated. 12 to 16, the wafer cassette is represented by CS1 and CS2, and the transfer robot is represented by RB1 and CS2.
RB2, RB3, RB4, and the cleaning machine is CL1-1,
CL1-2, CL2-1, and CL2-2. ov1, T. ov2, and the polishing table is TT
1, TT2, the top ring is represented by TR1, TR2, the loading table (or pusher) of the index table is represented by In-1L, In-2L, and the unloading table (or pusher) of the index table is: It is represented by In-1UL and In-2UL.

As shown in FIGS. 12 to 16, one of the wafers is transferred from the wafer cassette (CS1) to the transfer robot (R).
B1) → reversing machine (T.ov1) → transfer robot (RB)
2) → Loading table (or pusher) (In-1)
L) → Top ring (TR1) → Polishing table (TT)
1) → Unloading table (or pusher) (In
-1UL) → transfer robot (RB3) → cleaning machine (CL1)
-1) → transfer robot (RB2) → reversing machine (T.ov)
2) → Transfer robot (RB1) → Cleaning machine (CL2-1)
→ Transfer robot (RB1) → Wafer cassette (CS1)
Via the path to.

The other wafer is transferred from the wafer cassette (CS2) to the transfer robot (RB1) to the reversing machine (To.o).
v1) → transfer robot (RB2) → loading table (or pusher) (In-2L) → top ring (T
R2) → Polishing table (TT2) → Unloading table (or pusher) (In-2UL) → Transfer robot (RB4) → Washer (CL1-2) → Transfer robot (R
B2) → reversing machine (T.ov2) → transfer robot (RB)
1) → Cleaning machine (CL2-2) → Transfer robot (RB1)
→ Via the path leading to the wafer cassette (CS2). FIG.
16 to FIG. 16, the index table 1
Two of the four tables 9 are one of the polishing tables 9
The other two tables transport the wafer supplied to the other polishing table 10. The wafer polished by the polishing table 9 and the wafer polished by the polishing table 10 are commonly handled by the index table 19, the transfer robot 6, the transfer robot 2, and the reversing machines 4 and 5.

FIG. 17 is a plan view showing the arrangement of each part of the polishing apparatus according to the second embodiment of the present invention. FIG.
The polishing apparatus shown in FIG. 7 has two rotatable load / unload stages 1 on which a wafer cassette 40 for storing a large number of semiconductor wafers is placed. A transfer robot 2 having two hands is arranged at a position on the load / unload stage 1 at which each wafer cassette 40 can be reached.

One of the two hands of the transfer robot 2 holds only a clean semiconductor wafer, and the other hand holds only a dirty wafer. On both sides of the transfer robot 2, two cleaning machines 3 for cleaning and drying the semiconductor wafer after polishing are arranged. Each washing machine 3 is installed at a position where the hand of the transfer robot 2 can reach. A reversing machine 4 for reversing the semiconductor wafer to a position connecting the line between the center 2c of the transfer robot 2 and the washing machine 3 and a position symmetrical to the load / unload stage 1 and accessible by the hand of the transfer robot 2; Machine 5 is arranged.

The reversing machine 4 has both a chuck mechanism for chucking the semiconductor wafer and a reversing mechanism for reversing the front and back surfaces of the semiconductor wafer. The reversing machine 4 processes only a clean semiconductor wafer. The reversing machine 5 includes a rinsing mechanism for cleaning the semiconductor wafer in addition to the chuck mechanism and the reversing mechanism. The reversing machine 5 processes only a dirty semiconductor wafer.

With reference to a line L1 connecting the centers 4c and 5c of the wafers to be chucked by the reversing machine 4 and the reversing machine 5,
A transfer robot 6 having two hands is disposed at a position symmetrical with the transfer robot 2. Transfer robot 6
Is disposed at a position where the hand of the transfer robot 6 can reach the reversing machines 4 and 5. One of the two hands of the transfer robot 6 holds only a clean semiconductor wafer, and the other hand holds only a dirty semiconductor wafer.

A cleaning machine 7 for cleaning the semiconductor wafer after polishing is arranged on both sides of the transfer robot 6. The washing machine 7 is different from the washing machine 3 in the washing method. The cleaning machine 7 is installed at a position where the hand of the transfer robot 6 can reach. Two transfer robots 8 having one hand are disposed at positions opposite to the reversing machines 4 and 5 with respect to a line connecting the centers of the two cleaning machines 7. The transfer robot 8 is arranged at a position where the hand of the transfer robot 8 can reach each washing machine 7. And 2
Between the transfer robots 8, there is a wafer station 20.
The wafer station 20 includes a rinsing mechanism. The wafer station 20 is surrounded by a waterproof tank in order to prevent rinsing water from splashing due to rinsing and has three shutters for loading and unloading wafers.

The polishing apparatus has a housing 30 surrounding each device, and the inside of the housing 30 is divided into a plurality of rooms (including a polishing room and a cleaning room). The two transfer robots 8 to the load / unload stage 1 are arranged in the cleaning chamber 30A. Then, the transfer robot 8 in the cleaning room 30A
The partition wall 31 is installed at a position adjacent to the partition wall 31.
A polishing room 30B, which is a room different from the cleaning room 30A, is disposed on the opposite side of the polishing room 30B. The polishing chamber 30
B, two polishing tables 9 and 10 and two top rings 12 for holding one semiconductor wafer and polishing while pressing the semiconductor wafer against the polishing tables 9 and 10 are arranged. I have.

In the polishing chamber 30B, two index tables 19 installed corresponding to the two top rings 12 are installed. Each index table 19 is a load pusher 1 for transferring a wafer.
5 and an unload pusher 16 for transferring a wafer from the top ring 12. The load pusher 15 and the unload pusher 16 are arranged at equal intervals on the same circumference on the index table 19, and one set of the load pusher 15 and the unload pusher 16 is installed on the index table 19. That is, one set of the load pusher 15 and the unload pusher 16 is prepared for each of the polishing tables 9 and 10. When the index table 19 supporting each pusher rotates, the load pusher 15 and the unload pusher 16 are moved to the first position, that is, the position where the transfer robot 8 can be transferred to and from the transfer robot 8, and the second position, that is, the top position. The position where the ring 12 and the wafer can be transferred can be moved. The load pusher 15 moves to the substantially same position as the unload pusher 16, and the unload pusher 16 moves to the same position as the load pusher 15 at the same time, and the load and unload pushers move to the top ring 12 and the transfer robot 8 substantially simultaneously. Will be reachable. Each index table 19 can be controlled independently.

The load pusher 15 and the unload pusher 16 have a function of moving up and down, and can access the top ring 12 and the transfer robot 8. The load pusher 15 is provided with an automatic alignment mechanism.
Only when rising to receive the wafer towards
The automatic centering mechanism operates, and the load pusher 15 moves within a range where the mounting error of the top ring 12 can be absorbed, and can receive a wafer from the top ring 12. When the transfer robot 8 receives a wafer from the unload pusher 16, the unload pusher 16 is located at the lower end and positioned so as not to move on the spot.

The unload pusher 16 is provided with an automatic alignment mechanism. The automatic alignment mechanism operates only when the unload pusher 16 is raised to receive a wafer from the top ring 12, and the unload pusher 16 The wafer can be received from the top ring 12 by moving within a range in which the mounting error of the top ring 12 can be absorbed. When the transfer robot 8 receives a wafer from the unload pusher 16, the unload pusher 16 is located at the lower end and positioned so as not to move on the spot. The structure of the pushers 15 and 16 is shown in FIG.
The structure is substantially the same as the structure shown in FIGS.

The top ring 12 is located at the first position.
A rinsing nozzle for supplying a cleaning liquid to the wafer carried out of the apparatus and cleaning the wafer is provided. At the second position, a cleaning nozzle for supplying a cleaning liquid to the top ring 12 after unloading the wafer and performing cleaning is provided. At the first position and the second position, sensors for confirming the presence or absence of a wafer are provided. Notches are formed in the partition wall between the load pusher 15 and the transfer robot 8 and between the unload pusher 16 and the transfer robot 8 so that a wafer can pass therethrough, and a shutter 18 is arranged in each notch.

FIG. 18 is a view showing the relationship among the top ring 12, the polishing tables 9, 10, and the pusher portion. FIG.
As shown in FIG. 8, the top ring 12 is suspended from the top ring arm 11 by a rotatable shaft 32. The top ring arm 11 is a rotary shaft 3 that can be positioned.
3 and the top ring 12 is accessible to each of the polishing tables 9 and 10.
Each top ring 12 can press a semiconductor wafer against the polishing tables 9 and 10 with an arbitrary load by an air cylinder provided in the top ring arm 11. Above the central portion of the polishing tables 9 and 10, a polishing liquid nozzle 13 for flowing a polishing liquid for polishing is disposed. In addition, each polishing table 9, 10
Is arranged.
A polishing cloth or a grindstone (fixed abrasive) is mounted on the upper surfaces of the polishing tables 9 and 10. An index table 19 having a load pusher 15 and an unload pusher 16 is provided adjacent to the rotation shaft 33 of the top ring 12.

Next, the overall operation of the polishing apparatus configured as described above will be described. Semiconductor wafers before polishing are stored in a wafer cassette 40,
The cassette 40 is placed on the load / unload stage 1. After all the processing conditions in the apparatus have been input, the apparatus starts automatic operation. In the present polishing apparatus, several polishing operations can be performed. In operation 1, however, an odd number of semiconductor wafers (hereinafter, referred to as wafers) counted from the upper stage of the wafer cassette are sequentially polished on the polishing table 9. Then, the even-numbered wafer is polished on the polishing table 10. Hereinafter, the polishing step will be described step by step.

1. The load / unload stage 1 adjusts the angle, and changes the direction of the wafer cassette 40 until the transfer robot 2 can transfer the wafer. 2. The transfer robot 2 adjusts the angle and height, sucks the wafer in the wafer cassette 40 with a clean hand, and pulls the wafer out of the wafer cassette 40.

3. The transfer robot 2 adjusts the angle and height again while holding the wafer, and transfers the wafer to the reversing machine 4. 4. The reversing device 4 chucks the wafer transported by the transport robot 2, and after confirming that the wafer has been normally chucked, rotates the wafer by 180 ° so that the surface to be processed of the wafer faces downward.

5. After confirming that the reversing machine 4 has been normally rotated by 180 °, the transfer robot 6 adjusts the angle and the height, releases the chuck of the reversing machine 4, and receives the wafer from the reversing machine 4 with a clean hand. 6. The transfer robot 6 adjusts the angle and height again, and transfers the wafer to the wafer station 20. After confirming that the paper has been correctly transported, the load pusher 15
When the transfer robot 8 is in the position and there is no wafer in the load pusher 15, the transfer robot 8 receives the wafer from the wafer station 20, and then the shutter 18 opens to transfer the wafer to the load pusher 15.

7. When it is confirmed that the wafer has been transferred to the load pusher 15, the load pusher 15 moves to the second position centering on the center of the index table 19 and to the wafer transfer position to the top ring 12. 8. After confirming the movement, the load pusher 15 moves up and chucks the outer periphery of the top ring 12. Thereafter, the stage on which the wafer is mounted further moves up, and the back surface of the wafer comes into contact with the holding portion of the top ring 12, but a buffer mechanism using a spring provided below the stage works to prevent damage to the wafer. When the load pusher 15 stops moving up by a predetermined moving amount, the top ring 12 vacuum-adsorbs the wafer.

9. When it is confirmed that the top ring 12 normally sucks the wafer, the rotating shaft 33 supporting the top ring arm 11 rotates, and the top ring 12 moves to the polishing position on the polishing table 9. 10. When it is confirmed that the top ring 12 has moved to the polishing position, the polishing table 9 that has been rotating at the idling speed and the top ring 12 that has been stopped rotate at the previously input speed in the same direction, and the polishing liquid nozzle 13 The type and flow rate of the polishing liquid that have been input in advance flow down onto the polishing table 9. Thereafter, the top ring 12 is lowered, and when it is confirmed that the top ring 12 has reached the polishing table 9, a pressing pressure corresponding to the previously input condition is applied to the top ring 12, and the top ring 12 is input in advance. Polishing is performed only for a time. The polishing may be performed while the type of the polishing liquid is changed successively to this step, or while the liquid containing no solid component flows down.

11. When the polishing is completed, the polishing liquid nozzle 13
Stops the supply of the polishing liquid, and the top ring 12 sucks the wafer. The shaft 33 supporting the top ring arm 11 rotates to a position where the top ring 12 is separated from the polishing table 9 by half. Next, the top ring 12 rises,
The top ring 12 further rotates to the second position. 12. After confirming that the top ring 12 is located on the second position, the unload pusher 16 is raised to chuck the top ring 12, and the lifting is completed. At this time, the wafer mounting portion of the unload pusher 16 secures a predetermined gap with the wafer held by the top ring 12. Next, the top ring 12 cuts off the vacuum, blows air or nitrogen and pure water, and separates the wafer onto the unload pusher 16.

13. After the top ring 12 leaves the wafer, the unload pusher 16 moves down. 14． When the unload pusher 16 descends and confirms that the wafer is on the unload pusher 16, the index table 19 rotates and moves the unload pusher 16 to the first position. In this state, pure water is injected from the rinse nozzle 42 to clean the top ring 12,
At the same time, the cleaning liquid is sprayed from the rinse nozzle 43 to clean the wafer. At this time, the wafer before polishing is transferred to the load pusher 15 by the transfer robot 8. And the load pusher 15 is located at the second position,
Pure water is sprayed from the rinse nozzle 44 to wash away the pure water dropped from the top ring 12. After that, the polishing process is performed in the same manner as described above.

15. After the rinsing cleaning of the top ring 12 and the wafer is completed, the shutter 18 is opened, the transfer robot 8 adjusts the angle and height, and receives the wafer from the unload pusher 16. Thereafter, after confirming that the load pusher 15 has transferred the wafer to the top ring 12, the index table 19 is rotated to move the unload pusher 16 to the second position. 16. After receiving the wafer from the unload pusher 16, the transfer robot 8 adjusts the angle and the height, and transfers the wafer to the cleaning machine 7. At the same time, the cleaning machine 7 chucks the wafer.

17. The cleaning machine 7 confirms that the wafer has been normally chucked, and performs the first-stage double-side cleaning of the wafer after the polishing. 18. When the cleaning of the cleaning machine 7 is completed, the transfer robot 6 adjusts the angle and the height, inserts a dirty hand into the cleaning machine 7 from another opening, and receives the wafer. 19. The transfer robot 6 adjusts the angle and height again, and transfers the same to the reversing machine 5, which simultaneously chucks the wafer. 20. After confirming that the reversing machine 5 has chucked the wafer normally, pure water is sprayed from a pure water rinsing nozzle attached to the reversing machine 5 to prevent drying of the wafer, and at the same time, the reversing machine 5 rotates by 180 °. With the polished surface of the wafer facing up.

21. After confirming that the reversing device 5 has been normally rotated by 180 °, the transfer robot 2 adjusts the angle and the height, and receives the wafer from the reversing device 5 with a dirty hand, and at the same time, the reversing device 5 removes the chuck. Open. 22. The transfer robot 2 adjusts the angle and height again, and transfers the wafer to the cleaning machine 3, and at the same time, the cleaning machine 3 chucks the wafer. 23. The cleaning machine 3 confirms that the wafer has been normally chucked, and performs the second-stage cleaning of the wafer after polishing. 24. After the cleaning of the cleaning machine 3 is completed, the transfer robot 2 adjusts the angle and the height, and receives the wafer from the cleaning machine 3 with a clean hand.

25. The transfer robot 2 adjusts the angle and height again, and the polished wafer is transferred to the position where the wafer in the wafer cassette 40 was stored before the wafer was processed. 26. The second and subsequent even-numbered wafers are conveyed to the polishing table 10 in the same manner as described above, and the top ring 12 is moved and conveyed in the opposite direction to the top ring 12 of the polishing table 9 in the same order as described above. And is returned to the wafer cassette.

In the operations described in the above 1 to 26, an example has been described in which the wafers stored in one wafer cassette are sorted to the table 9 for odd-numbered wafers and to the table 10 for even-numbered wafers. The software may be configured to sort the wafers in the wafer cassette to the table 9 and the wafers in other wafer cassettes to the table 10. Further, the apparatus may be configured so that two or more cassettes can be assigned to each table, and may be configured as a continuous single-wafer apparatus.

In the example shown in FIG. 18, the pusher is installed on the index table. However, the pusher may be installed below the index table as in the embodiment shown in FIG. Further, the index table does not necessarily have to be in the form of a table, and may have a form in which a load pusher and an unload pusher are fixed to a rotating shaft.

FIGS. 19 to 34 are schematic process diagrams showing the operation of an index table (rotary transporter) according to another embodiment. 19 to 34, the transfer robots 6, 8 and 8 are represented by RB2, RB3 and RB4, the loading table of the index table 19 is represented by LD1 and LD2, and the unloading table of the index table 19 is ULD1. And UL
It is represented by D2. The top ring is represented by TR1 and TR2. In the initial state shown in FIG. 19, the two loading tables LD1 and LD2 are located adjacent to the respective top rings TR1 and TR2,
The two unloading tables ULD1 and ULD2 are located adjacent to the transfer robots RB3 and RB4. Each table includes a load table LD1 for the first polishing table and an unload table UL for the first polishing table.
D1, Unloading table ULD for second polishing table
2, and a loading table LD2 for the second polishing table
Are located clockwise around the rotation axis of the index table 19.

Next, the operation of the index table will be described with reference to FIG.
This will be described with reference to FIGS. In Step 1, as shown in FIG. 19, the transfer robot RB2 holds the wafer 1 to be polished on the first polishing table (TT1). In step 2, as shown in FIG. 20, the index table is shifted 90 degrees clockwise from the state shown in FIG.
゜ Rotate. Thereafter, the transfer robot RB2 transfers the wafer to the loading table LD1. In step 3,
As shown in FIG. 21, the index table rotates and returns to the state shown in FIG. In step 4, FIG.
As shown in (1), the pusher rises to receive the wafer 1 from the placing table, and transfers the wafer 1 to the top ring TR1. Thereafter, the top ring TR1 starts polishing the wafer 1. The transfer robot RB2 uses the second polishing table (TT
The wafer 2 to be polished in 2) is held.

In step 5, as shown in FIG. 23, the index table rotates 90 ° counterclockwise from the state shown in FIG. Then, the transfer robot RB2
Transports the wafer 2 to the loading table LD2. In step 6, as shown in FIG. 24, the index table rotates and returns to the state shown in FIG. 22 (FIG. 19). The transfer robot RB2 holds the wafer 3 to be polished on the first polishing table (TT1). In step 7, FIG.
As shown in (2), the pusher rises to receive the wafer 2 from the placing table, and transfers the wafer 2 to the top ring TR2. Thereafter, the top ring TR2 starts polishing the wafer 2. In step 8, as shown in FIG. 26, the index table is rotated 90 ° clockwise from the state shown in FIG. Thereafter, the transfer robot RB2 transfers the wafer 3 to the loading table LD1.

In step 9, as shown in FIG. 27, the index table rotates 180 ° counterclockwise from the state shown in FIG. The transfer robot RB2 is the second
The wafer 4 to be polished is held by the polishing table (TT2). In step 10, as shown in FIG.
After the polishing of the wafer is completed on the polishing table (TT1), the pusher moves up to receive the polished wafer 1 from the top ring TR1, and the unloading table ULD1
Hand over to The transfer robot RB2 transfers the wafer 4 to the loading table LD2. In step 11, FIG.
As shown in FIG. 9, the index table rotates 90 ° clockwise from the state shown in FIG. Thereafter, the polished wafer 1 is washed with pure water at this position. The transfer robot RB2 holds the wafer 5 to be polished on the first polishing table (TT1). In step 12, as shown in FIG. 30, the pusher rises to receive the wafer 3 from the placing table, and transfers the wafer 3 to the top ring TR1. Thereafter, the top ring TR1 starts polishing the wafer 3. The transfer robot RB3 receives the cleaned and polished wafer 1 from the unloading table ULD1.

In step 13, as shown in FIG. 31, the index table is rotated 90 ° clockwise from the state shown in FIG. Thereafter, the transfer robot RB2 transfers the wafer 5 to the loading table LD1. In step 14, as shown in FIG. 32, after the polishing of the wafer at the second polishing table (TT2) is completed, the pusher rises to receive the polished wafer 2 from the top ring TR2, and the unloading table ULD2 Hand over to In step 15, as shown in FIG. 33, the index table is rotated 90 ° counterclockwise from the state shown in FIG. Thereafter, the polished wafer 2 is washed with pure water at this position. The transfer robot RB2 holds the wafer 6 to be polished by the second polishing table (TT2). In step 16, as shown in FIG. 34, the pusher rises, receives the wafer 4 from the loading table LD2, and delivers it to the top ring TR2. Thereafter, the top ring TR2 starts polishing the wafer 4. The transfer robot RB4 receives the cleaned and polished wafer 2 from the unloading table ULD2.

[0087]

As described above, according to the present invention,
It is possible to reduce the time required to transport a polishing target such as a semiconductor wafer to the top ring, and the number of processed polishing targets per unit time (throughput)
Can be dramatically increased. In addition, in the conventional apparatus, the number of top rings is increased, and the throughput is increased by simultaneously polishing the objects to be polished, and between the objects to be polished due to individual differences of the top rings caused by increasing the number of top rings. Although the in-plane uniformity after polishing varied, in the present invention, it is possible to increase throughput with a small number of top rings by increasing the transport speed.

[Brief description of the drawings]

FIG. 1 is a plan view showing an arrangement configuration of each part of a polishing apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a top ring and a polishing table in the apparatus shown in FIG.

FIG. 3 is a plan view showing details of an index table type A;

FIG. 4 is an elevation view showing details of an index table type A;

FIG. 5 is a plan view showing details of an index table type B;

FIG. 6 is an elevation view showing details of an index table type B;

FIG. 7 is a plan view showing details of a linear motion table type.

FIG. 8 is an elevational view showing details of a linear motion table type.

FIG. 9 is a plan view showing a relationship among a top ring, an index table, a pusher, and a transfer robot.

FIG. 10 is an explanatory diagram of the operation of the pusher.

FIG. 11 is a plan view showing a modification of the first embodiment of the polishing apparatus according to the present invention.

FIG. 12 is a schematic process diagram showing a case where a semiconductor wafer is polished by the polishing apparatus shown in FIGS. 1 and 11;

FIG. 13 is a schematic process diagram showing a case where a semiconductor wafer is polished by the polishing apparatus shown in FIGS. 1 and 11;

FIG. 14 is a schematic process diagram showing a case where a semiconductor wafer is polished by the polishing apparatus shown in FIGS. 1 and 11;

FIG. 15 is a schematic process diagram showing a case where a semiconductor wafer is polished by the polishing apparatus shown in FIGS. 1 and 11;

FIG. 16 is a schematic process diagram showing a case where a semiconductor wafer is polished by the polishing apparatus shown in FIGS. 1 and 11;

FIG. 17 is a plan view showing an arrangement configuration of each part of a polishing apparatus according to a second embodiment of the present invention.

18 is a diagram showing a relationship among a top ring, a polishing table, and a pusher unit in the apparatus shown in FIG.

FIG. 19 is a schematic process diagram showing the operation of an index table (rotary transporter) according to another embodiment.

FIG. 20 is a schematic process diagram showing an operation of an index table (rotary transporter) according to another embodiment.

FIG. 21 is a schematic process diagram showing an operation of an index table (rotary transporter) according to another embodiment.

FIG. 22 is a schematic process diagram showing an operation of an index table (rotary transporter) according to another embodiment.

FIG. 23 is a schematic process diagram showing the operation of an index table (rotary transporter) according to another embodiment.

FIG. 24 is a schematic process diagram showing the operation of an index table (rotary transporter) according to another embodiment.

FIG. 25 is a schematic process diagram showing the operation of an index table (rotary transporter) according to another embodiment.

FIG. 26 is a schematic process diagram showing the operation of an index table (rotary transporter) according to another embodiment.

FIG. 27 is a schematic process diagram showing the operation of an index table (rotary transporter) according to another embodiment.

FIG. 28 is a schematic process diagram showing an operation of an index table (rotary transporter) according to another embodiment.

FIG. 29 is a schematic process diagram showing the operation of an index table (rotary transporter) according to another embodiment.

FIG. 30 is a schematic process diagram showing an operation of an index table (rotary transporter) according to another embodiment.

FIG. 31 is a schematic process diagram showing the operation of an index table (rotary transporter) according to another embodiment.

FIG. 32 is a schematic process diagram showing the operation of an index table (rotary transporter) according to another embodiment.

FIG. 33 is a schematic process diagram showing the operation of an index table (rotary transporter) according to another embodiment.

FIG. 34 is a schematic process diagram showing an operation of an index table (rotary transporter) according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Load / unload stage 2,6,8 Transfer robot 3,7 Cleaning machine 4,5 Reversing machine 9,10 Polishing table 11 Top ring arm 12 Top ring 13 Abrasive liquid nozzle 14 Dresser 15,16 Pusher (Place table) 17 Pusher Reference Signs List 18 Shutter 19 Index table 20 Wafer station 21 Cover 25 Transport mechanism 42, 43, 44 Rinse nozzle 30 Housing 30A Cleaning chamber 30B Polishing chamber 31 Partition wall 33, 41 Rotation axis 34 Air cylinder 40 Wafer cassette 101 Pin 102 Wafer 105, 114 Cylinder 106 Stage 111, 112 Spring 113 Shock absorber

Claims (10)

[Claims] 1. A plurality of polishing tables each having a polishing surface, and a plurality of top rings provided respectively corresponding to the plurality of polishing tables, holding a polishing object, and pressing the polishing object against the polishing surface. , Is installed at a position where the plurality of top rings can be reached,
A transport mechanism having a plurality of parts located on a predetermined circumference from the rotation center and holding the object to be polished, and having an index function for indexing the plurality of parts, and between the transport mechanism and the top ring A polishing apparatus, comprising: a pusher for transferring an object to be polished. 2. A plurality of polishing tables each having a polishing surface, and a plurality of top rings provided respectively corresponding to the plurality of polishing tables and holding a polishing object and pressing the polishing object against the polishing surface. The plurality of top rings are provided corresponding to each of the top rings at reachable positions, and have a plurality of portions that are located on a predetermined circumference from a rotation center and hold a polishing object, and the plurality of top rings are provided. A polishing apparatus, comprising: a plurality of transport mechanisms having an index function for indexing a portion; and a pusher for transferring an object to be polished between the transport mechanism and a top ring. 3. A plurality of polishing tables each having a polishing surface, and a plurality of top rings provided respectively corresponding to the plurality of polishing tables and holding a polishing object and pressing the polishing object against the polishing surface. A transport mechanism having an index function of transferring an object to be polished to the top ring, wherein each of the plurality of top rings is movable to a position above the polishing table and a position above the transport mechanism. A polishing apparatus, comprising: 4. A polishing table having a polishing surface; a top ring for holding a polishing object and pressing the polishing object against the polishing surface; a robot for transporting the polishing object in an apparatus; A transfer mechanism for transferring the object to be polished between a position for transferring the object and a position for transferring the object to be polishing to the robot, wherein the transfer mechanism moves between the two positions; A polishing apparatus characterized by moving linearly. 5. A polishing table having a polishing surface, a top ring for holding a polishing object and pressing the polishing object against the polishing surface, and a transport mechanism for transporting the polishing object between two positions in the apparatus. Wherein the transport mechanism includes at least two pedestals for holding the object to be polished, and the at least two pedestals are respectively located at different heights so as to be individually movable in a planar position. A polishing apparatus characterized in that: 6. The apparatus according to claim 1, wherein the transport mechanism comprises a loading table for holding the object to be polished before polishing, and an unloading table for holding the object to be polished after polishing. The polishing apparatus according to any one of claims 1 to 5, wherein 7. The apparatus according to claim 1, wherein each of the top rings is rotatably moved around a rotation axis, and is located at a position above the polishing table and a position above the transport mechanism. 2. The polishing apparatus according to claim 1. 8. The polishing apparatus according to claim 1, wherein the transport mechanism includes a first table for transferring an object to be polished to be polished by one of the plurality of polishing tables, and another polishing table of the plurality of polishing tables. The polishing apparatus according to any one of claims 1 to 3, further comprising a second table for transferring a polishing target to be polished. 9. The transport mechanism includes four pedestals for supplying a polishing object to a first polishing table and a second polishing table, and loads on the four pedestals for the first polishing table. A loading table, an unloading table for the first polishing table, an unloading table for the second polishing table, and a loading table for the second polishing table. 4. The device according to claim 1, wherein the device is arranged clockwise around the rotation axis.
The polishing apparatus according to claim 1. 10. The transfer mechanism according to claim 3, wherein a pusher for transferring the object to be polished between the transport mechanism and the top ring is disposed below the transport mechanism or on the transport mechanism. The polishing apparatus according to any one of the preceding claims.