JP3897507B2 - Polishing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a polishing apparatus that flattens and mirrors the surface of a polishing object such as a semiconductor wafer, and more particularly to a polishing apparatus that includes an index table (rotary transporter) for supplying the polishing object.
[0002]
[Prior art]
In the semiconductor manufacturing process, polishing is performed to make the wafer surface flat and mirror surface in the semiconductor wafer manufacturing process, and polishing is performed to make the layer formed on the device flat and mirror surface in the device manufacturing process. Yes. A polishing apparatus is used in the polishing process in the semiconductor wafer manufacturing process and the device manufacturing process. This polishing apparatus is called a chemical mechanical polishing apparatus.
[0003]
A conventional polishing apparatus is a dedicated polishing apparatus that performs only polishing, and a semiconductor wafer that has been polished is placed in a movable water tank and conveyed to the next cleaning step. However, in the method in which the polishing process and the cleaning process are performed separately, the cleanliness of the clean room is impaired, and the wafer transport after the polishing has to be relied on manually transporting means. Moreover, since two types of apparatuses, a polishing apparatus and a cleaning machine used in the subsequent cleaning process, are required, a large installation space is required.
[0004]
Therefore, in order to clean the polishing process and reduce the installation space of the apparatus, the polishing process and the cleaning process are performed in the same apparatus, the semiconductor wafer is put in the apparatus in a dry state, and the semiconductor wafer is cleaned after processing. Polishing equipment has been developed that realizes a dry-in / dry-out system that dispenses from the equipment in a dry state.
[0005]
On the other hand, a polishing apparatus that performs only polishing is also improved so that the cleanness of the clean room can be maintained, and the production capacity of the polishing apparatus and the cleaning machine used in the cleaning process after polishing is increased, and the polishing apparatus and the cleaning machine in the polishing process are improved. It has become possible to reduce the number of installations and reduce the installation space equivalent to or more than the dry-in / dry-out polishing apparatus.
[0006]
[Problems to be solved by the invention]
However, in the polishing apparatus that performs only polishing, the transfer means for transferring the semiconductor wafer after polishing is still dependent on the transfer means by hand, and when the transfer means is automated, the wafer storage method Since it becomes a mobile water tank, handling is difficult and the subject remains in the said conveyance means. In addition, the conventional dry-in / dry-out polishing apparatus has a low production capacity per unit time and unit installation area, has a large number of apparatuses in each polishing process, requires a large installation space, There is a problem that the management cost becomes high.
[0007]
An object of the present invention is to solve all the problems of the above-described prior art, and is applicable to the above-described dry-in / dry-out type polishing apparatus, and a unit time and a unit of a polishing object such as a semiconductor wafer. An object of the present invention is to provide a polishing apparatus capable of increasing the processing capacity per installation area.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, an aspect of the present invention is a polishing table having a polishing surface, a top ring that holds a polishing object and presses the polishing object against the polishing surface, and a polishing object between two positions in the apparatus. A transport mechanism for transporting an object, the transport mechanism, Two linear rails arranged at different positions in the height direction and two pedestals that can slide along each of the rails, the two pedestals do not interfere with each other in the height direction The two pedestals can be moved to the polishing object conveyance position of the top ring, and the polishing object is transferred to the top ring by the pusher at that position. Each of the two cradles is movable to a polishing object delivery position of the transfer robot, and the transfer robot and the polishing object are transferred at the position, and a rinse mechanism and a shutter are reached at the reachable position of the transfer robot. And a polishing object to be polished after being opened by opening the shutter into the station. It is characterized by this.
[0013]
ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to shorten the time which conveys polishing objects, such as a semiconductor wafer, to a top ring, and can increase the processing number (throughput) of the polishing object per unit time dramatically. .
In a preferred aspect of the present invention, the transport mechanism includes a loading table for holding a polishing object before polishing and an unloading table for holding a polishing object after polishing.
In a preferred aspect of the present invention, each top ring rotates around a rotation axis and is positioned above the polishing table and above the transport mechanism.
[0014]
Furthermore, in a preferred aspect of the present invention, a dresser dedicated to each polishing table is provided.
In a preferred aspect of the present invention, the pusher is installed below or on the transport mechanism.
In a preferred aspect of the present invention, the distances between the rotation shaft of the transport mechanism and the rotation shafts of the plurality of top rings are equal.
[0015]
In a preferred aspect of the present invention, the transport mechanism includes a first table for transferring a polishing object to be polished by one of the plurality of polishing tables, and another of the plurality of polishing tables. And a second pedestal for transferring a polishing object to be polished by the polishing table.
Furthermore, in a preferred aspect of the present invention, each of the first table and the second table includes a loading table on which a polishing object before polishing and a polishing object after polishing are mounted. And an unloading stand to be placed.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of a polishing apparatus according to the present invention will be described with reference to the drawings.
FIG. 1 is a plan view showing the arrangement of each part of the first aspect of the polishing apparatus according to the present invention.
The polishing apparatus shown in FIG. 1 includes two rotatable load / unload stages 1 on which a wafer cassette 40 for stocking a large number of semiconductor wafers is placed. A transfer robot 2 having two hands is arranged at a position where it can reach each wafer cassette 40 on the load / unload stage 1.
[0018]
Of the two hands in the transfer robot 2, the upper hand grips only a clean and dry semiconductor wafer, and the lower hand is a dirty (wet) wet wafer. Only grab. Two cleaning machines 3 for cleaning and drying the polished semiconductor wafer are disposed on both sides of the transfer robot 2. Each washing machine 3 is installed at a position where the hand of the transfer robot 2 can reach. A reversing device 4 and a reversing device 5 are disposed for reversing the semiconductor wafer at a position that can be reached by the hand of the transport robot 2 at a point symmetric with respect to the load / unload stage 1 with respect to the center 2c of the transport robot 2. Yes.
[0019]
The reversing machine 4 has both a chuck mechanism for chucking a 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, and the reversing machine 5 processes only dirty and wet semiconductor wafers.
[0020]
A line L connecting the centers 4c and 5c of the wafer to be chucked by the reversing machine 4 and the reversing machine 5. ₁ , A transfer robot 6 having two hands is arranged at a position symmetrical to the transfer robot 2. The transfer robot 6 is arranged at a position where the hand of the transfer robot 6 can reach the cradle 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 holds only a clean and dry semiconductor wafer, and the lower hand holds only a dirty and wet semiconductor wafer.
[0021]
Two cleaning machines 7 for cleaning the polished semiconductor wafer are disposed on both sides of the transfer robot 6. The washing machine 7 differs 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 having one hand are arranged at positions opposite to the reversing machines 4 and 5 with each cleaning machine 7 interposed therebetween. The transfer robot 8 is disposed at a position where the hand of the transfer robot 8 can reach the table for each cleaning machine 7 and the index table 19.
[0022]
The polishing apparatus includes a housing 30 so as to surround each device, and the housing 30 is partitioned 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. A partition wall 31 is installed at a position adjacent to the transfer robot 8 in the cleaning chamber 30 </ b> A, and a polishing chamber 30 </ b> B that is a separate room from the cleaning chamber 30 </ b> A is disposed on the opposite side of the partition wall 31.
The polishing chamber 30B includes two polishing tables 9, 10 and two top rings 12 for holding one semiconductor wafer and polishing the semiconductor wafer while pressing the semiconductor wafer against the polishing tables 9, 10. Has been placed.
[0023]
FIG. 2 is a view showing the relationship between the top ring 12 and the polishing tables 9 and 10. As shown in FIG. 2, 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 rotatable rotary shaft 33 so that the top ring 12 can access the polishing tables 9 and 10. Each top ring 12 can press the 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 portions of the polishing tables 9 and 10, a polishing liquid nozzle 13 is disposed for flowing a polishing liquid for polishing. A dresser 14 for dressing the polishing tables 9 and 10 is arranged. A polishing cloth or a grindstone (fixed abrasive) is mounted on the upper surfaces of the polishing tables 9 and 10.
[0024]
Next, a pusher unit as a delivery device for delivering a semiconductor wafer between the transfer robots 6 and 8 and the top ring 12 will be described. The pusher portion is installed at the center position of the space surrounded by the two polishing tables 9 and 10 and the three transfer robots 6 and 8. There are three types of pushers, two index table types (rotary transporter type) and one linear motion table type. Next, three types of pusher portions will be described.
[0025]
1) Index table type (rotary transporter type) A
3 and 4 are diagrams showing details of the index table type A, FIG. 3 is a plan view, and FIG. 4 is an elevation view. As shown in FIGS. 3 and 4, one pusher 17, which is a dedicated wafer transfer mechanism, is provided in each top ring 12 within the swivel range of the top ring 12. Each pusher 17 constitutes a dedicated transport mechanism for delivering a 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 the 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, the transfer robot 6 and the transfer robot 8 is disposed (see FIG. (See FIGS. 1, 3 and 4). The index table 19 can be rotated 360 ° in the horizontal direction, and rotates a positioning mechanism (index mechanism) and a table 15 or 16 on which a semiconductor wafer is placed (15 is a loading table, 16 is an unloading table). A total of four are provided, two at equal intervals on a predetermined circumference from the center. The cradles 15 and 16 need not be dedicated for loading and unloading.
[0026]
As shown in FIG. 1, the rotation center of the index table 19 must be arranged at a position where each table 15, 16 can access all of the transfer robot 6, the transfer robot 8, and the top ring 12. In the present embodiment, the rotary shafts of the index table 19 are arranged at equal distances from the polishing tables 9 and 10. Further, the rotation axis of the index table 19 is disposed at an equal distance from the top ring rotation shaft 33. A cover 21 is provided so that the index table 19 is included in the polishing chamber 30B. The cover 21 is formed with a notch having a size capable of loading and unloading the wafer into and from the index table 19, and a shutter 18 is provided in the notch. A cleaning nozzle 43 for cleaning the wafer for supplying a cleaning liquid to the wafer is installed at a wafer transfer position with the robot in the cover 21. A cleaning nozzle 42 is provided at the position of the pusher 17 to supply a cleaning liquid to the polished top ring 12 for cleaning. The cleaning nozzle 42 for cleaning the top ring 12 can also be used for preventing the top ring 12 from being dried during the time when the wafer polishing process is not performed.
[0027]
2) Index table type (rotary transporter type) B
5 and 6 are diagrams 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 can rotate 360 ° in the horizontal direction and includes a positioning mechanism (index mechanism). On the index table 19, pushers 15 and 16 (15 is a load pusher and 16 is an unload pusher) of a wafer transfer mechanism for carrying wafers in and out of the top ring 12 from the center of rotation to a predetermined circle. Four units are installed at equal intervals on the circumference. The pusher need not be dedicated for loading and unloading.
[0028]
The pushers 15 and 16 have an elevating function and can move up and down between a wafer transfer position to the top ring 12 and a supply position to transfer the wafer to the pushers 15 and 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. Since the configuration of the cover 21, the shutter 18, the cleaning nozzle for cleaning the wafer, and the cleaning nozzle for cleaning the top ring is the same as that of Type A, the description thereof is omitted.
[0029]
3) Linear motion table type
7 and 8 are diagrams showing details of the linear motion table type. FIG. 7 is a plan view and FIG. 8 is an elevation view. As shown in FIGS. 7 and 8, one pusher 17, which is a dedicated wafer transfer mechanism, is provided in each top ring 12 within the swivel range of 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 supply position to transfer the semiconductor wafer to the pusher 17. Two transfer mechanisms 25 for transferring a semiconductor wafer between the pusher 17 and the transfer robot 6 and transfer robot 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 placed. Each of the tables 15 and 16 is located above the pusher 17 and individually in a planar position in the linear direction. It is movable. The table 15 is a loading table for transferring a semiconductor wafer to the top ring 12, and the table 16 is an unloading table for receiving a semiconductor wafer from the top ring 12.
[0030]
The transport mechanism 25 linearly moves between the top ring 12, the transport robot 8 arranged in the same row as the pushers 17, and the transport robot 6 positioned in the center. Each transport mechanism 25 is different at a position in the height direction. position Are provided with two linear rails 26 arranged on the surface. Each rail 26 includes a pedestal 15 or 16 that can slide along the rail. The two platforms 15 and 16 of each transport mechanism 25 are vertical It arrange | positions so that it may not mutually interfere in a direction, and it can move to a horizontal direction separately. The cradles 15 and 16 are movable on the rails 26 by a ball screw mechanism and a motor (not shown), respectively. By taking such an arrangement, when the two cradles 15 and 16 are moved, the positions of the two cradles 15 and 16 can be replaced in a plane. The moving means of the transport mechanism 25 includes a positioning mechanism. When the placing tables 15 and 16 on which the semiconductor wafer is placed have moved to the wafer transfer position of the top ring 12, the pusher 17 positioned below the table can push up the semiconductor wafer and transfer the semiconductor wafer to the top ring 12. is there. Conversely, when the pedestals 15 and 16 on which no semiconductor wafer is placed have moved to the same position, the pusher 17 receives the semiconductor wafer from the top ring and descends so that the semiconductor wafer can be placed on the pedestals 15 and 16. .
[0031]
The transfer mechanism 25 is located in the polishing chamber 30B, and a notch having a size capable of loading and unloading the wafer into and from the transfer mechanism 25 is formed in the partition of the polishing chamber 30B. A shutter 18 is provided in the notch. Is provided. A cleaning nozzle for cleaning the wafer for supplying a cleaning solution to the wafer is installed at a wafer transfer position with the robot in the partition wall. A cleaning nozzle is provided at the position of the pusher 17 for supplying and cleaning the top ring 12 after polishing. The cleaning nozzle for cleaning the top ring 12 can also be used for preventing the top ring 12 from drying while the wafer polishing process is not being performed.
[0032]
Next, the overall operation of the polishing apparatus configured as described above will be described.
The semiconductor wafer before polishing is stocked in the wafer cassette 40, and the cassette 40 is placed on the load / unload stage 1. After all processing conditions in the apparatus are input, the apparatus starts automatic operation. In this polishing apparatus, several polishing steps can be performed. In the operation described below, an odd number of semiconductor wafers (hereinafter referred to as wafers) counted from the upper stage of the wafer cassette are transferred to the polishing table 9. Polishing is performed sequentially, and even-numbered wafers are polished on the polishing table 10. Hereinafter, the polishing process will be described step by step.
[0033]
In this case, the procedure of the pusher part of the index table type A is described, and the procedure of the pusher part of the index table type B is described in (). For the linear motion type pusher, only the rotation operation of the index table 19 is changed to a linear motion, and other operations are the same as those of the index table types A and B.
[0034]
1. The load / unload stage 1 adjusts the angle and changes the orientation of the wafer cassette 40 to an angle that the transfer robot 2 can transfer.
2. The transfer robot 2 adjusts the angle and height, sucks the wafer that has entered the wafer cassette 40 with a clean hand, and removes the wafer from the wafer cassette 40.
[0035]
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 machine 4 chucks the wafer transported by the transport robot 2, and after confirming that the wafer has been normally chucked, the reversing machine 4 rotates the wafer 180 ° so that the processing surface of the wafer faces downward.
[0036]
5). After confirming that the reversing machine 4 has normally rotated 180 °, the transfer robot 6 adjusts the angle and height, opens 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 again adjusts the angle and height, and when it is confirmed that there is no wafer on the table 15 (pusher 15) on the index table 19, the shutter 18 opens, and the wafer is loaded on the table 15 (pusher 15). Transport.
[0037]
7). When it is confirmed that the wafer has been transferred to the cradle 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). When it is confirmed that the cradle 15 (the pusher 15) has moved to a position where the top ring 12 can be accessed, the pusher 17 rises, and when the wafer is received from the cradle 15, the pusher 17 further rises and chucks the top ring 12. . (The pusher 15 rises and chucks the top ring 12). Thereafter, the stage on which the wafer is further moved up, the back surface of the wafer comes into contact with the holding portion of the top ring 12, and at the same time, the top ring 12 vacuum-sucks the wafer.
[0038]
9. When it is confirmed that the top ring 12 has normally attracted the wafer, the pusher 17 is lowered, and after confirming that the descent is completed, the index table 19 rotates 90 ° or 270 degrees in the opposite direction. At this time, the unloading table 16 (the pusher 16) is positioned at the wafer transfer position of the top ring 12. Further, simultaneously with the rotation of the index table 19, the rotation shaft supporting the top ring arm 11 rotates, and the top ring 12 moves to the polishing position on the polishing table 9.
[0039]
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, and the type and flow rate of the polishing liquid input in advance from the polishing liquid nozzle 13 are supplied. It flows down onto the polishing table 9. Thereafter, the top ring 12 descends, and when it is confirmed that the top ring 12 has reached the polishing table 9, a pressing pressure corresponding to a previously input condition is applied to the top ring 12 and input in advance. Polishing is performed only for the time. While the wafer is being polished in these processes, the next unpolished wafer is also transferred in the same procedure, and transferred onto the loading table 15 (the pusher 15).
[0040]
11. When the polishing is finished, the abrasive liquid nozzle 13 stops supplying the abrasive liquid, and the top ring 12 vacuum-sucks the wafer. After confirming that the wafer is sucked, the shaft 33 supporting the top ring arm 11 is attached to the top ring 12. It rotates so that it may come to the position which remove | deviates from the said polishing table 9 only by half.
12 When it is confirmed that the top ring 12 has come to a position half off 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 while the top ring 12 is above, ie, the top ring. Move to the wafer transfer position. At this time, since the index table 19 remains in the state of step 9 described above, the unloading table 16 (pusher 16) is positioned at the wafer transfer position of the top ring 12.
[0041]
13. After confirming that the top ring 12 is positioned on the pusher 17 (the pusher 16), the pusher 17 (the pusher 16) rises to chuck the top ring 12, and at the same time, the top ring 12 shuts off the vacuum, and air or nitrogen Then, pure water is blown to separate the wafer onto the pusher 17 (pusher 16).
14 After the top ring 12 removes the wafer, the pusher 17 moves down to the bottom of the pedestal. (The pusher 16 is lowered to a level at which the transfer robot 8 can transfer the wafer.)
[0042]
15. When the pusher 17 (pusher 16) is lowered and it is confirmed that the wafer is on the table 16 (pusher 16), the index table 19 is rotated 90 ° or 270 ° and is transferred to the table 15 (pusher 15) in advance. The next wafer before polishing moves to the wafer transfer position of the top ring 12, and is transferred and polished in the same manner as described above. At the same time, pure water is sprayed from the rinse nozzle to clean the top ring 12. Further, pure water is supplied to the wafer in order to prevent the wafer on the table 16 from drying. In order to recover the optimum polishing surface of the polishing table 9 or 10 after polishing the previous wafer and before polishing the subsequent wafer, dressing by the dresser 14 is performed.
16. When the next wafer is transferred to the top ring 12, the index table 19 is rotated, and when it is confirmed that the placing table 16 (the pusher 16) has moved to a position where the transfer robot 8 can reach, the shutter 18 opens. Then, the transfer robot 8 adjusts the angle and height, and receives the wafer from the placing table 16 (the pusher 16).
[0043]
17. After the transfer robot 8 receives the wafer from the table 16 (pusher 16), the shutter 18 is closed, the transfer robot 8 adjusts the angle and height, and transfers the wafer to the cleaning machine 7. At the same time, the cleaning machine 7 sets the wafer. Chuck.
18. The cleaning machine 7 confirms that the wafer has been normally chucked, and performs the first stage cleaning of the wafer after the polishing.
[0044]
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 reach the cleaning machine 7, adjusts the angle and height at the same time, and receives the wafer with a dirty hand.
20. The transfer robot 6 adjusts the angle and the height again and transfers it to the reversing machine 5. At the same time, the reversing machine 5 chucks the wafer.
[0045]
21. After confirming that the reversing machine 5 has normally chucked the wafer, pure water is sprayed from a pure water rinse nozzle attached to the reversing machine 5 to prevent the wafer from drying, and at the same time, the reversing machine 5 rotates 180 °. Turn the polished surface of the wafer up.
22. After confirming that the reversing machine 5 has normally rotated 180 °, the transfer robot 2 adjusts the angle and height, and receives the wafer from the reversing machine 5 with a dirty hand. At the same time, the reversing machine 5 releases the chuck. To do.
[0046]
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 polished wafer.
[0047]
25. After the cleaning by the cleaning machine 3 is completed, the transfer robot 2 adjusts the angle and height, and receives a wafer from the cleaning machine 3 with a clean hand.
26. 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 was stored before being processed.
27. Even-numbered and subsequent wafers are transferred 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.
[0048]
Next, details of the operation of the pusher portion of the index type A will be described with reference to FIG. 9 and FIG. FIG. 9 is a plan view showing the relationship among the top ring, the index table, the pusher, and the transfer robot, and FIG. 10 is an operation explanatory view of the pusher.
As shown in FIG. 9, the wafer 102 to be transferred to the top ring 12 is transferred to the index table 19 by the transfer robot 6 from the direction 210. The wafer to be transported is placed on the shoulder of the pin 101 with a step assembled on the index table 19 by the robot hand 160. At this time, the wafer holding portion of the robot hand 160 and the contact portion between the pins 101 and the wafer 102 are different portions of the outer peripheral portion of the wafer. Thereafter, the index table 19 is rotated by a motor 200 (see FIG. 4), and the wafer 102 moves to the transfer position 215 to the top ring 12 and is positioned above the pusher 17. FIG. 10A illustrates a state in which the wafer 102 is placed on the index table 19 and conveyed above the pusher 17. In this figure, the top ring 12 is positioned above the index table 19, and the pusher 17 is disposed below the index table 19.
[0049]
Next, the pusher 17 is lifted by the cylinder 105, pushes up the wafer 102 placed on the shoulder of the pin 101, and the wafer 102 is placed on the stage 106 of the pusher 17. At this time, the contact portion between the stage 106 and the wafer 102 is different from the contact portion between the pins 101 and the wafer 102, and is partially shared with the contact portion between the robot hand 160 and the wafer 102. FIG. 10B shows a state where the cylinder 105 of the pusher 17 is stroked and the wafer 102 on the index table 19 and the stage 106 of the pusher 17 are in contact with each other. 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.
[0050]
FIG. 10C shows a state where the cylinder 105 further strokes, the wafer 102 is lifted from the index table 19, and the stage 109 is in contact with the top ring 12. When the stage 106 picks up the wafer 102 from the index table 19, the alignment guide 107 and the alignment guide 108 are not in contact with each other, so that they can move freely in a planar position. This alignment operation can be performed by incorporating the linear guide into the A part (see FIG. 10A) so as to be orthogonal. Further, the guide 110 of the stage 109 is tapered, and the pusher 17 is guided so that the top ring 12 is accommodated in the guide 110 when it comes into contact with the top ring 12. That is, the pusher 17 has a position adjusting function with respect to the top ring 12. And in order to relieve the impact when the stage 109 and the top ring 12 contact, the spring 111 and the spring 112 are incorporated, and the shock absorber 113 is incorporated so that the contact position can be adjusted.
[0051]
FIG. 10D shows a state in which the cylinder 114 further strokes from the state of FIG. 10C, the stage 106 on which the wafer 102 is placed is raised, and the wafer 102 is in contact with the suction surface of the top ring 12. . Even in this state, the spring 111 and the spring 112 act so that the stage 106 does not press the wafer 102 against the top ring 12 more than necessary.
With these series of operations, the wafer 102 on the index table 19 is transferred to the top ring 12.
[0052]
When the wafer 102 is placed on the index table 19 from the top ring 12, the pusher 17 is operated in the state shown in FIG. 10C, and the wafer 102 is detached from the top ring 12 in this state. When the wafer 102 is detached from the top ring 12, the pusher 17 is moved in the reverse order of the series of operations for adsorbing the wafer 102 to the top ring 12 so as to be in FIG. 10 (c) → FIG. 10 (b) → FIG. 10 (a). By operating the wafer 102, the wafer 102 adsorbed on the top ring 12 is transferred onto the index table 19. At this time, the wafer 102 is placed on the pins 101 of the index table 19. Thereafter, the index table 19 is rotated by the motor 200 and rotated to the unloading position of the wafer 102, and the wafer 102 is unloaded in the direction of the arrow 211 by the robot hand 180 of the transfer robot 8.
[0053]
FIG. 11 is a plan view showing a modification of the first aspect of the polishing apparatus according to the present invention. In this embodiment, two load pushers 15 are arranged on the diagonal line of the index table 19, and two unload pushers 16 are arranged on the diagonal line of the index table 19. A total of four pushers 15 and 16 are installed on the index table 19.
[0054]
12 to 16 are schematic process diagrams showing an example of polishing a wafer by the polishing apparatus shown in FIGS. 1 and 11, in which a wafer is taken out from one wafer cassette (CS1), and a polishing process. Each process until the wafer cassette (CS1) is returned to the wafer cassette (CS1) after the cleaning process, and each process until the wafer is taken out from the other wafer cassette (CS2), returned to the wafer cassette (CS2) via the polishing process and the cleaning process. Is illustrated. 12 to 16, the wafer cassette is represented by CS1, CS2, the transfer robot is represented by RB1, RB2, RB3, RB4, and the cleaning machine is represented by CL1-1, CL1-2, CL2-1, CL2-2, The reversing machine is T.W. ov1, T. It is represented by ov2, the polishing table is represented by TT1, TT2, the top ring is represented by TR1, TR2, the index table loading platform (or pusher) is represented by In-1L, In-2L, and the index table is unloaded. The cradle (or pusher) is represented by In-1UL and In-2UL.
[0055]
As shown in FIGS. 12 to 16, one wafer has a wafer cassette (CS1) → transfer robot (RB1) → reversing machine (T.ov1) → transfer robot (RB2) → loading table (or pusher). (In-1L) → Top ring (TR1) → Polishing table (TT1) → Unloading stand (or pusher) (In-1UL) → Transport robot (RB3) → Cleaning machine (CL1-1) → Transport robot (RB2) → Reversing machine (T.ov2) → Transfer robot (RB1) → Cleaning machine (CL2-1) → Transport robot (RB1) → Wafer cassette (CS1).
[0056]
The other wafer is: wafer cassette (CS2) → transfer robot (RB1) → reversing machine (T.ov1) → transfer robot (RB2) → loading stand (or pusher) (In-2L) → top ring (TR2) → Polishing table (TT2) → Unloading stand (or pusher) (In-2UL) → Conveying robot (RB4) → Cleaning machine (CL1-2) → Conveying robot (RB2) → Reversing machine (T .Ov2) → Transfer robot (RB1) → Cleaning machine (CL2-2) → Transport robot (RB1) → Wafer cassette (CS2).
As can be seen from FIGS. 12 to 16, two of the four tables of the index table 19 supply wafers to one polishing table 9, and the other two tables supply the other polishing table 10. A wafer to be transported. The wafer polished by the polishing table 9 and the wafer polished by the polishing table 10 are handled in common by the index table 19, the transfer robot 6, the transfer robot 2, and the reversing machines 4 and 5.
[0057]
FIG. 17 is a plan view showing the arrangement of each part of the second aspect of the polishing apparatus according to the present invention.
The polishing apparatus shown in FIG. 17 includes two rotatable load / unload stages 1 on which a wafer cassette 40 for stocking a large number of semiconductor wafers is placed. A transfer robot 2 having two hands is arranged at a position where it can reach each wafer cassette 40 on the load / unload stage 1.
[0058]
One of the two hands in the transfer robot 2 grips only a clean semiconductor wafer, and the other hand grips only a dirty wafer. Two cleaning machines 3 for cleaning and drying the polished semiconductor wafer are disposed on both sides of the transfer robot 2. Each washing machine 3 is installed at a position where the hand of the transfer robot 2 can reach. A reversing device 4 for reversing the semiconductor wafer to a position where the hand of the transport robot 2 can reach the line connecting the center 2c of the transport robot 2 and the cleaning machine 3 at a position symmetrical to the load / unload stage 1 and a reversal. Machine 5 is arranged.
[0059]
The reversing machine 4 has both a chuck mechanism for chucking a 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, and the reversing machine 5 processes only dirty semiconductor wafers.
[0060]
A transfer robot 6 having two hands is arranged at a position symmetrical to the transfer robot 2 with reference to a line L1 connecting the centers 4c and 5c of the wafer to be chucked by the reversing machine 4 and the reversing machine 5. ing. The 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 grips only a clean semiconductor wafer, and the other hand grips only a dirty semiconductor wafer.
[0061]
On both sides of the transfer robot 6, a cleaning machine 7 for cleaning the semiconductor wafer after polishing is disposed. The washing machine 7 differs from the washing machine 3 in the washing method. The washing 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 arranged at positions opposite to the reversing machines 4 and 5 with reference to a line connecting the centers of the two washing machines 7. The transfer robot 8 is disposed at a position where the hand of the transfer robot 8 can reach each cleaning machine 7. A wafer station 20 is installed between the two transfer robots 8, and the wafer station 20 includes a rinse mechanism. The wafer station 20 is surrounded by a waterproof tank in order to prevent rinsing water from being scattered by rinsing, and has three surfaces for shutters for loading and unloading the wafer.
[0062]
The polishing apparatus includes a housing 30 so as to surround each device, and the housing 30 is partitioned 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. A partition wall 31 is installed at a position adjacent to the transfer robot 8 in the cleaning chamber 30 </ b> A, and a polishing chamber 30 </ b> B that is a separate room from the cleaning chamber 30 </ b> A is disposed on the opposite side of the partition wall 31.
The polishing chamber 30B includes two polishing tables 9, 10 and two top rings 12 for holding one semiconductor wafer and polishing the semiconductor wafer while pressing the semiconductor wafer against the polishing tables 9, 10. Has been placed.
[0063]
In the polishing chamber 30B, two index tables 19 installed corresponding to the two top rings 12 are installed. Each index table 19 includes a load pusher 15 for transferring a wafer and an unload pusher 16 for transferring the wafer from the top ring 12. The load pusher 15 and the unload pusher 16 are arranged on the same circumference on the index table 19 at equal intervals, and a pair of the load pusher 15 and the unload pusher 16 are 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. Further, when the index table 19 supporting each pusher is rotated, the load pusher 15 and the unload pusher 16 are in the first position, that is, the position where the transfer robot 8 and the wafer can be delivered, and the second position, that is, the top. The position where the ring 12 and the wafer can be transferred can be moved. The load pusher 15 is moved to substantially the same position as the unload pusher 16 and simultaneously the unload pusher 16 is moved to substantially the same position as the load pusher 15, and the load and unload pushers are moved to the top ring 12 and the transfer robot 8 almost simultaneously. Reachable. Each index table 19 can be controlled independently.
[0064]
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. The automatic alignment mechanism works only when the load pusher 15 is raised to receive the wafer toward the top ring 12. The wafer can be received from the top ring 12 by moving the range in which the mounting error can be absorbed. When the transfer robot 8 receives a wafer from the unload pusher 16, the unload pusher 16 is positioned at the lower end and positioned so as not to move on the spot.
[0065]
The unload pusher 16 is provided with an automatic alignment mechanism. The automatic alignment mechanism works only when the unload pusher 16 is lifted 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 the range in which the mounting error can be absorbed. When the transfer robot 8 receives a wafer from the unload pusher 16, the unload pusher 16 is positioned at the lower end and positioned so as not to move on the spot. The structure of the pushers 15 and 16 is substantially the same as the structure shown in FIGS. 10 (a) to 10 (d).
[0066]
Further, a rinse nozzle is provided at the first position for supplying a cleaning liquid to the wafer carried out from the top ring 12 and cleaning it. A cleaning nozzle is provided at the second position for supplying a cleaning liquid to the top ring 12 after the wafer is unloaded and cleaning the top ring 12. Sensors for confirming the presence or absence of a wafer are installed at the first position and the second position. Notches are formed in the partition walls between the load pusher 15 and the transfer robot 8 and between the unload pusher 16 and the transfer robot 8 so that the wafer can pass, and a shutter 18 is disposed in each notch.
[0067]
FIG. 18 is a diagram showing the relationship among the top ring 12, the polishing tables 9, 10 and the pusher portion. As shown in FIG. 18, 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 rotatable rotary shaft 33 so that the top ring 12 can access the polishing tables 9 and 10. Each top ring 12 can press the 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 portions of the polishing tables 9 and 10, a polishing liquid nozzle 13 is disposed for flowing a polishing liquid for polishing. A dresser 14 for dressing the polishing tables 9 and 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 installed adjacent to the rotation shaft 33 of the top ring 12.
[0068]
Next, the overall operation of the polishing apparatus configured as described above will be described.
The semiconductor wafer before polishing is stocked in the wafer cassette 40, and the cassette 40 is placed on the load / unload stage 1. After all processing conditions in the apparatus are input, the apparatus starts automatic operation. In this polishing apparatus, several polishing steps can be performed. In operation 1, 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. The even number of wafers are polished by the polishing table 10. Hereinafter, the polishing process will be described step by step.
[0069]
1. The load / unload stage 1 adjusts the angle and changes the orientation of the wafer cassette 40 to an angle that the transfer robot 2 can transfer.
2. The transfer robot 2 adjusts the angle and height, sucks the wafer that has entered the wafer cassette 40 with a clean hand, and pulls the wafer out of the wafer cassette 40.
[0070]
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 machine 4 chucks the wafer transported by the transport robot 2, and after confirming that the wafer has been normally chucked, the reversing machine 4 rotates the wafer 180 ° so that the processing surface of the wafer faces downward.
[0071]
5). After confirming that the reversing machine 4 has normally rotated 180 °, the transfer robot 6 adjusts the angle and height, opens 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. If the load pusher 15 is in the first position and the load pusher 15 has no wafer after confirming that it has been correctly transferred, the transfer robot 8 receives the wafer from the wafer station 20 and then the shutter 18 Open and transfer the wafer to the load pusher 15.
[0072]
7). When it is confirmed that the wafer has been transferred to the load pusher 15, the load pusher 15 moves from the center of the index table 19 to the second position and the wafer transfer position to the top ring 12.
8). After confirming the movement, the load pusher 15 rises and chucks the outer periphery of the top ring 12. Thereafter, the stage on which the wafer is further moved 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 at the lower part of the stage works to prevent damage to the wafer. The load pusher 15 stops rising when it is raised by a preset amount of movement, and then the top ring 12 vacuum-sucks the wafer.
[0073]
9. When it is confirmed that the top ring 12 has normally attracted 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 rotated at the idling speed and the stopped top ring 12 are rotated in the same direction at a speed that is input in advance, and the abrasive nozzle 13 A previously inputted type and flow rate of the polishing liquid flows down onto the polishing table 9. Thereafter, the top ring 12 descends, and when it is confirmed that the top ring 12 has reached the polishing table 9, a pressing pressure corresponding to a previously input condition is applied to the top ring 12 and input in advance. Polishing is performed only for the time. Polishing may be performed while changing the type of the abrasive liquid continuously in this step, or flowing down a liquid containing no solid content.
[0074]
11. When the polishing is finished, the abrasive liquid nozzle 13 stops supplying the abrasive 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 half off from the polishing table 9. Next, the top ring 12 rises and the top ring 12 further rotates to the second position.
12 After confirming that the top ring 12 is positioned on the second position, the unload pusher 16 rises to chuck the top ring 12 and finishes raising. At this time, the wafer mounting portion of the unload pusher 16 secures a predetermined gap between the wafer and the wafer held on 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.
[0075]
13. After the top ring 12 leaves the wafer, the unload pusher 16 is lowered.
14 When the unload pusher 16 is lowered and it is confirmed 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 sprayed from the rinse nozzle 42 to clean the top ring 12, and at the same time, a cleaning liquid is sprayed from the rinse nozzle 43 to clean the wafer. At this time, a wafer before polishing is transferred to the load pusher 15 by the transfer robot 8. The load pusher 15 is located at the second position, and pure water is jetted from the rinse nozzle 44 to wash away pure water dripped from the top ring 12. Thereafter, a polishing process is performed as described above.
[0076]
15. After the top ring 12 and the wafer are rinsed, 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 height and transfers the wafer to the cleaning machine 7. At the same time, the cleaning machine 7 chucks the wafer.
[0077]
17. The cleaning machine 7 confirms that the wafer has been normally chucked, and performs double-sided cleaning of the first stage of the wafer after polishing.
18. When the cleaning of the cleaning machine 7 is completed, the transfer robot 6 adjusts the angle and height, inserts a dirty hand into the cleaning machine 7 through another opening, and receives the wafer.
19. The transfer robot 6 adjusts the angle and the height again and transfers it to the reversing machine 5. At the same time, the reversing machine 5 chucks the wafer.
20. After confirming that the reversing machine 5 has normally chucked the wafer, pure water is sprayed from a pure water rinse nozzle attached to the reversing machine 5 to prevent the wafer from drying, and at the same time, the reversing machine 5 rotates 180 °. Turn the polished surface of the wafer up.
[0078]
21. After confirming that the reversing machine 5 has normally rotated 180 °, the transfer robot 2 adjusts the angle and height, and at the same time the reversing machine 5 receives the wafer from the reversing machine 5 with a dirty hand. 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 polished wafer.
24. After the cleaning of the cleaning machine 3 is completed, the transfer robot 2 adjusts the angle and height, and receives a wafer from the cleaning machine 3 with a clean hand.
[0079]
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 being processed.
26. Even-numbered and subsequent wafers are transferred to the polishing table 10 in the same manner as described above, and the top ring 12 is moved in the direction opposite to the top ring 12 of the polishing table 9 and transferred in the same order as described above. And then returned to the wafer cassette.
[0080]
In the operation described in the above 1 to 26, the embodiment has been described in which the wafers stored in one wafer cassette are distributed to the table 9 for the odd-numbered sheets and to the table 10 for the even-numbered sheets. The software may be configured to distribute the wafers to the table 9 and the wafers in other wafer cassettes to the table 10. Furthermore, the apparatus may be configured so that two or more cassettes can be assigned to each table, and a continuous sheet type apparatus configuration may be adopted.
[0081]
In the example shown in FIG. 18, the pusher is installed on the index table, but the pusher may be installed below the index table as in the embodiment shown in FIG. 4. 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.
[0082]
19 to 34 are schematic process diagrams showing the operation of the index table (rotary transporter) according to another embodiment. In FIG. 19 to FIG. 34, the transfer robots 6, 8 and 8 are represented by RB2, RB3 and RB4, the loading table for the index table 19 is represented by LD1 and LD2, and the unloading table for the index table 19 is ULD1. And ULD2. The top ring is indicated by TR1 and TR2. In the initial state shown in FIG. 19, the two loading platforms LD1 and LD2 are positioned adjacent to the top rings TR1 and TR2, and the two unloading platforms ULD1 and ULD2 are the transfer robots RB3 and RB4. Is located adjacent to Each table includes a loading table LD1 for the first polishing table, an unloading table ULD1 for the first polishing table, an unloading table ULD2 for the second polishing table, and a second polishing table. The loading table LD2 is positioned around the rotation axis of the index table 19 in the clockwise direction.
[0083]
Next, the operation of the index table 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 by the first polishing table (TT1).
In step 2, as shown in FIG. 20, the index table is rotated 90 degrees clockwise from the state shown in FIG. 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, as shown in FIG. 22, the pusher ascends to receive the wafer 1 from the 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 holds the wafer 2 to be polished by the second polishing table (TT2).
[0084]
In step 5, as shown in FIG. 23, the index table is rotated 90 degrees counterclockwise from the state shown in FIG. Thereafter, the transfer robot RB2 transfers 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 by the first polishing table (TT1).
In step 7, as shown in FIG. 25, the pusher ascends to receive the wafer 2 from the 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 degrees clockwise from the state shown in FIG. Thereafter, the transfer robot RB2 transfers the wafer 3 to the loading table LD1.
[0085]
In step 9, as shown in FIG. 27, the index table is rotated 180 degrees counterclockwise from the state shown in FIG. The transfer robot RB2 holds the wafer 4 to be polished by the second polishing table (TT2).
In step 10, as shown in FIG. 28, after the polishing of the wafer is completed on the first polishing table (TT1), the pusher is raised to receive the polished wafer 1 from the top ring TR1, and the unloading table ULD1. Pass to. The transfer robot RB2 transfers the wafer 4 to the loading table LD2.
In step 11, as shown in FIG. 29, the index table is rotated 90 degrees clockwise from the state shown in FIG. Thereafter, the polished wafer 1 is cleaned with pure water at this position. The transfer robot RB2 holds the wafer 5 to be polished by the first polishing table (TT1).
In step 12, as shown in FIG. 30, the pusher ascends to receive the wafer 3 from the 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 polished wafer 1 after cleaning from the unloading table ULD1.
[0086]
In step 13, as shown in FIG. 31, the index table is rotated 90 degrees 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 is completed on the second polishing table (TT2), the pusher is raised to receive the polished wafer 2 from the top ring TR2, and the unloading table ULD2 Pass to.
In step 15, as shown in FIG. 33, the index table is rotated 90 degrees counterclockwise from the state shown in FIG. Thereafter, the polished wafer 2 is cleaned 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 ascends, receives the wafer 4 from the loading table LD2, and transfers it to the top ring TR2. Thereafter, the top ring TR2 starts polishing the wafer 4. The transfer robot RB4 receives the cleaned polished wafer 2 from the unloading table ULD2.
[0087]
【The invention's effect】
As described above, according to the present invention, it is possible to shorten the time for transporting a polishing object such as a semiconductor wafer to the top ring, and dramatically increase the number of processed objects (throughput) per unit time. Can be increased. Further, in the conventional apparatus, the throughput is increased by increasing the number of top rings and simultaneously polishing the objects to be polished, and between the objects to be polished due to individual differences in the top ring resulting from increasing the number of top rings. In-plane uniformity after polishing has varied, but in the present invention, it is possible to increase the throughput with less top ring by increasing the conveyance speed.
[Brief description of the drawings]
FIG. 1 is a plan view showing an arrangement configuration of each part of a first aspect of a polishing apparatus according to the present invention.
FIG. 2 is a view 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.
FIG. 4 is an elevational view showing details of the index table type A.
5 is a plan view showing details of an index table type B. FIG.
FIG. 6 is an elevational view showing details of the index table type B.
FIG. 7 is a plan view showing details of a linear motion table type.
FIG. 8 is an elevation view showing details of the 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 aspect of the polishing apparatus according to the present invention.
12 is a schematic process diagram showing a case where polishing of a semiconductor wafer is performed by the polishing apparatus shown in FIGS. 1 and 11. FIG.
13 is a schematic process diagram showing a case where polishing of a semiconductor wafer is performed by the polishing apparatus shown in FIGS. 1 and 11. FIG.
14 is a schematic process diagram showing a case where polishing of a semiconductor wafer is performed by the polishing apparatus shown in FIGS. 1 and 11. FIG.
15 is a schematic process diagram showing a case where polishing of a semiconductor wafer is performed by the polishing apparatus shown in FIGS. 1 and 11. FIG.
16 is a schematic process diagram showing a case where polishing of a semiconductor wafer is performed by the polishing apparatus shown in FIGS. 1 and 11. FIG.
FIG. 17 is a plan view showing the arrangement of each part of the second aspect of the polishing apparatus according to the present invention.
18 is a view showing a relationship among a top ring, a polishing table, and a pusher portion in the apparatus shown in FIG.
FIG. 19 is a schematic process diagram showing an 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 an operation of an index table (rotary transporter) according to another embodiment.
FIG. 24 is a schematic process diagram showing an operation of an index table (rotary transporter) according to another embodiment.
FIG. 25 is a schematic process diagram showing an operation of an index table (rotary transporter) according to another embodiment.
FIG. 26 is a schematic process diagram showing an operation of an index table (rotary transporter) according to another embodiment.
FIG. 27 is a schematic process diagram showing an 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 an 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 illustrating an operation of an index table (rotary transporter) according to another embodiment.
FIG. 32 is a schematic process diagram showing an operation of an index table (rotary transporter) according to another embodiment.
FIG. 33 is a schematic process diagram showing an 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]
1 Load / unload stage
2,6,8 transfer robot
3,7 Washing machine
4,5 reversing machine
9,10 Polishing table
11 Top ring arm
12 Top ring
13 Abrasive nozzle
14 Dresser
15,16 pusher
17 Pusher
18 Shutter
19 Index table
20 Wafer station
21 Cover
25 Transport mechanism
42, 43, 44 Rinse nozzle
30 Housing
30A Cleaning room
30B Polishing room
31 Bulkhead
33, 41 Rotating shaft
34 Air cylinder
40 Wafer cassette
101 pin
102 wafers
105,114 cylinders
106 stages
111, 112 spring
113 Shock absorber

Claims (4)

A polishing table having a polishing surface;
A top ring that holds the polishing object and presses the polishing object against the polishing surface;
A transport mechanism for transporting a polishing object between two positions in the apparatus,
The transport mechanism includes two straight rails arranged at different positions in the height direction, and two cradles that can slide along each of the rails. It is possible to move individually in the horizontal direction so as not to interfere with each other in the direction, and each of the two stands can be moved to the polishing object conveyance position of the top ring, and the polishing object can be moved by the pusher at this position. the to pass received in the top ring, two stand's each have movable in polishing an object delivery position of the transfer robot, passes the transfer robot and polishing the object at said position,
A polishing apparatus , wherein a station having a rinse mechanism and a shutter is disposed at a reachable position of the transfer robot, and a polishing object to be polished is carried into the station by opening the shutter and performing rinse cleaning .   The polishing apparatus according to claim 1, wherein the transport mechanism includes a loading table that holds a polishing object before polishing and an unloading table that holds a polishing object after polishing. .   The polishing apparatus according to claim 1, wherein the top ring rotates around a rotation shaft and is located at a position above the polishing table and a position above the transport mechanism.   The transport mechanism includes a transport robot having an upper hand for gripping a clean and dry polishing object and a lower hand for gripping a dirty and wet polishing object. Item 2. The polishing apparatus according to Item 1.

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