JP5744382B2 - Substrate processing apparatus and substrate processing method - Google Patents

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method, and more particularly to a substrate processing apparatus and a substrate processing method used for polishing a substrate such as a semiconductor wafer flatly.

  In recent years, as semiconductor devices are highly integrated, circuit wiring is becoming finer and the distance between wirings is becoming narrower. In the manufacture of semiconductor devices, many types of materials are repeatedly formed in a film shape on a silicon wafer to form a laminated structure. In order to form this laminated structure, a technique for flattening the surface of the wafer is important. As one means for flattening the surface of such a wafer, a polishing apparatus (also referred to as a chemical mechanical polishing apparatus) that performs chemical mechanical polishing (CMP) is widely used.

  This chemical mechanical polishing (CMP) apparatus generally includes a polishing table to which a polishing pad is attached, a top ring that holds a wafer, and a nozzle that supplies a polishing liquid onto the polishing pad. While supplying the polishing liquid onto the polishing pad from the nozzle, the wafer is pressed against the polishing pad by the top ring, and the top ring and the polishing table are moved relative to each other to polish the wafer and flatten the surface.

  In addition to such a CMP apparatus, the substrate processing apparatus is an apparatus having a function of cleaning and further drying a polished wafer. In such a substrate processing apparatus, it is required to improve the throughput of the substrate processing. Since the substrate processing apparatus includes various processing units that perform polishing, cleaning, and the like, a delay in processing in each processing unit decreases the throughput of the entire substrate processing apparatus. For example, in a conventional substrate processing apparatus, a plurality of polishing units are provided, but only one cleaning line is provided, so that a plurality of polished wafers can be simultaneously cleaned and dried. There wasn't. In addition, among the plurality of processing steps on the cleaning line (primary cleaning, secondary cleaning, drying, etc.), the processing step with the slowest processing time becomes the rate-limiting step for the entire process, which is the processing time for the entire process ( (Throughput) was also determined.

  The throughput of the entire substrate processing apparatus may be influenced not only by processing units such as a polishing unit and a cleaning unit, but also by a transfer mechanism that transfers the wafer. Furthermore, the wafer transfer operation between the top ring and the transfer mechanism also affects the overall throughput. Thus, the overall throughput of the substrate processing apparatus depends on various processing steps and transfer steps.

  For example, the substrate processing apparatus has a linear transporter for transporting a wafer between a plurality of polishing units. The linear transporter moves the wafer linearly in the horizontal direction and conveys the wafer to the wafer delivery position of each polishing unit. Thereafter, the wafer is pushed up toward the top ring by a pusher provided separately from the Nilia transporter. As described above, since the horizontal movement and the vertical movement of the wafer are separately performed by the linear transporter and the pusher, the time required for transporting the wafer becomes long.

  Further, it is necessary to provide a pusher for each polishing unit at the wafer delivery position, and it is also necessary to provide an XY stage for finely adjusting the wafer delivery position between the top ring and the pusher. For this reason, the entire wafer transport mechanism is structurally complicated, and it is necessary to arrange a large number of associated wiring and piping. Furthermore, when this transfer mechanism fails, it may be necessary to access the wafer transfer position, and it may be difficult to perform a recovery operation.

  If the downtime of the substrate processing apparatus due to failure or maintenance becomes longer, the cost of wafer processing increases. For this reason, recently, there has been a demand for a substrate processing apparatus that can easily perform maintenance work, and further, there is a demand for reducing the number of parts, simplifying the structure, and reducing costs.

  For example, since the top ring swings between a polishing position on the polishing pad and a wafer transfer position, the swing mechanism of the top ring requires regular maintenance. This swing mechanism is composed of a bearing that supports the pivot shaft of the top ring, a motor that drives the pivot shaft, a speed reducer, and the like. The top ring head that supports the top ring is fixed to the upper end of a relatively long pivot, and the speed reducer and the motor are connected to the lower end. A bearing case is disposed outside the bearing, and this bearing case passes through a polisher pan that separates the polishing chamber from the chamber below it. Furthermore, the bearing case is installed under the polisher pan. As described above, since the top ring assembly including the top ring and the top ring head is relatively long and heavy, it may be inconvenient in terms of maintenance.

International Publication WO2007 / 099976

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a substrate processing apparatus and a substrate processing method capable of realizing high throughput.

Substrate in order to achieve the above object, an aspect of the present invention includes a polishing unit having a plurality of polishing units for polishing a plurality of substrates, respectively, and the transport mechanism for transporting a plurality of substrates continuously, which is polished A cleaning unit that cleans and dries the substrate, wherein the cleaning unit is continuously transported by a plurality of parallel cleaning lines for cleaning a plurality of substrates in parallel and the transport mechanism. A first transfer robot and a second transfer robot for distributing the plurality of substrates to any of the plurality of parallel cleaning lines, wherein the plurality of parallel cleaning lines includes a plurality of primary for primary cleaning of the substrate. A cleaning module and a plurality of secondary cleaning modules for performing secondary cleaning of the substrate. The primary cleaning module and the secondary cleaning module are each arranged in a vertical direction. The first transport robot moves up and down along a first support shaft extending in the vertical direction to be able to access the plurality of primary cleaning modules and the plurality of secondary cleaning modules; The second transfer robot moves up and down along a second support shaft extending in the vertical direction to be able to access the plurality of secondary cleaning modules. The substrate processing apparatus includes the primary cleaning module, A detector that detects a failure of the secondary cleaning module, and a cleaning line that avoids the failed cleaning module when the detector detects a failure of either the primary cleaning module or the secondary cleaning module select a, further comprising a control unit for switching to the selected the cleaning line in the cleaning either the substrate of the plurality of primary cleaning module In the case where there is a failure or the failure, the control unit performs the first transfer so as to transfer the substrate to the primary cleaning module that is not cleaning or does not perform the substrate cleaning among the plurality of primary cleaning modules. A substrate processing apparatus that controls a robot .
According to the present invention, even when a plurality of substrates are continuously carried into the cleaning unit, the substrates can be distributed to a plurality of cleaning lines as needed, and the plurality of substrates can be cleaned in parallel. Can do. In addition, since the substrate can be distributed to any of a plurality of cleaning lines according to the time required for cleaning or drying the substrate, the throughput of the entire process can be improved. Furthermore, if the processing times in the plurality of cleaning lines are leveled, the throughput of the entire process can be further improved.
In the present specification, the “cleaning line” refers to a movement path when a single substrate is cleaned by a plurality of cleaning modules inside the cleaning unit into which the substrate is loaded. The cleaning unit in the present invention has an advantage of having a function of cleaning a plurality of substrates simultaneously while having a function of cleaning a single substrate continuously.

According to an aspect of the present invention, the cleaning unit is characterized by having a first transfer robot and the second transport robot as sorting mechanism for distributing substrate to one of said plurality of cleaning lines. If comprised in this way, since a board | substrate (wafer) can be distributed according to the processing time between several cleaning lines, the processing time of a cleaning line can be equalized.
According to an aspect of the present invention, the plurality of cleaning lines, and characterized by having a plurality of primary cleaning module for cleaning the primary substrate, a plurality of secondary cleaning module for a substrate secondary wash To do. With this configuration, when a certain cleaning module fails, the cleaning module can be repaired or replaced with a new cleaning module without stopping the substrate cleaning process.
According to an aspect of the present invention, the plurality of primary cleaning module are arranged along the longitudinal direction, said plurality of secondary cleaning module is characterized in that it is arranged along the longitudinal direction. If comprised in this way, a footprint (installation area of the apparatus installed in the clean room etc.) can be made small. In this case, the substrate can be transported between a plurality of primary cleaning modules or between a plurality of secondary cleaning modules.

According to the aspect of the present invention, the cleaning unit includes a first transfer robot that can access the plurality of primary cleaning modules and the plurality of secondary cleaning modules, and a first transport robot that can access the plurality of secondary cleaning modules. It has 2 conveyance robots. If comprised in this way, a board | substrate can be conveyed rapidly and reliably by two conveyance robots.
In a preferred aspect of the present invention, the plurality of parallel cleaning lines include a temporary table on which a substrate is temporarily placed. If comprised in this way, the adjustment | control of the injection | throwing-in and taking-out time of a board | substrate to the cleaning module, and the conveyance path | route of the board | substrate in a washing | cleaning part can be changed flexibly.
In a preferred aspect of the present invention, the cleaning unit includes a plurality of drying modules that dry the plurality of substrates cleaned by the plurality of parallel cleaning lines. If comprised in this way, since a board | substrate can be carried out from a substrate processing apparatus in the dried state, a dry-in / dry-out type substrate processing apparatus can be provided.
In a preferred aspect of the present invention, the plurality of drying modules are arranged along the vertical direction. If comprised in this way, a footprint can be decreased.
In a preferred aspect of the present invention, the first transport robot has two hands of upper and lower two stages, the lower hand is used to transport the substrate before cleaning, and the upper hand is the substrate after cleaning. It is used for conveying.
In a preferred aspect of the present invention, the second transport robot has one hand for transporting the cleaned substrate.

According to another aspect of the present invention, a plurality of substrates are polished, and the polished substrates are continuously transferred to a plurality of parallel cleaning lines including a plurality of primary cleaning modules and a plurality of secondary cleaning modules. The primary cleaning module and the secondary cleaning module are arranged along a vertical direction, and the substrate can be moved up and down from the plurality of primary cleaning modules to the plurality of secondary cleaning modules. The substrate is unloaded from the plurality of secondary cleaning modules by a first transfer robot, and is moved by a second transfer robot capable of moving up and down, and the plurality of substrates are transferred to the first transfer robot and the second transfer robot. by distributing any of each of the plurality of juxtaposed washing line to wash the plurality of substrates in parallel by the plurality of juxtaposed washing line, When the plurality of cleaned substrates are dried and one of the primary cleaning module and the secondary cleaning module fails, a cleaning line that avoids the failed cleaning module is selected and the selected Switch to a cleaning line and if any of the plurality of primary cleaning modules is cleaning the substrate or is out of order, the substrate is not cleaned among the plurality of primary cleaning modules, or A substrate processing method comprising transporting a substrate to a primary cleaning module that has not failed . According to the present invention, it is possible to clean a plurality of substrates in parallel by distributing a plurality of substrates transported continuously to a plurality of cleaning lines. In addition, since the substrate can be distributed to any of a plurality of cleaning lines according to the time required for cleaning or drying the substrate, the throughput of the entire process can be improved. Furthermore, if the processing times in the plurality of cleaning lines are leveled, the throughput of the entire process can be further improved.

Further, since the plurality of substrates are cleaned in parallel, the plurality of substrates can be cleaned in a short time.
In a preferred aspect of the present invention, the plurality of substrates are cleaned at a predetermined time difference. As described above, since the plurality of substrates are cleaned at a predetermined time difference, for example, when it is necessary to transport the cleaned substrates one by one, the transport robot continuously transports the substrates at regular intervals. be able to. Therefore, the transfer of the substrate is not rate limiting, and the throughput of the entire process can be improved.

One reference example of the present invention is a polishing unit that polishes a substrate using a top ring that applies a pressing force to the substrate by a fluid pressure, a transport mechanism that transports the substrate, and a cleaning that cleans and dries the polished substrate. The top ring is swingably connected to a support shaft via a top ring head, and the pressure adjusting unit for adjusting the pressure of the fluid is connected to the top ring head. It is the substrate processing apparatus characterized by having installed in (1).

According to this reference example , the following conventional problems can be solved. In the conventional substrate processing apparatus, one pressure adjusting unit is provided outside the top ring head for a plurality of polishing units. Therefore, it is necessary to stop the pressure adjusting unit that adjusts the pressures of all the top rings because of some defects in the plurality of polishing units. According to this reference example , even when a plurality of polishing units are provided in the polishing unit, since the pressure adjusting unit is provided for each top ring head of each polishing unit, the operation of the polishing unit in which no failure has occurred continues. be able to. Accordingly, it is possible to prevent a decrease in the throughput of the entire substrate processing process. Here, from the viewpoint of reducing the weight of the top ring head, it is possible to reduce the size of the rotation mechanism and swing mechanism of the top ring, and to reduce the weight of the top ring head and the constituent members of the top ring (for example, top ring housing). It is preferable to form with materials (for example, vinyl chloride resin, fluororesin, etc.).

Further, according to this reference example , it is possible to improve the delay in the response of the pressing force of the top ring, which is a problem of the conventional substrate processing apparatus. That is, in the conventional substrate processing apparatus, since the pressure adjusting unit is provided outside the top ring head, the distance between the pressure adjusting unit and the top ring is long, and in response to a change command of the pressing force on the substrate, There was a problem that the change in pressing force was delayed. According to this reference example , since the pressure adjustment unit is installed in the top ring head, the distance between the top ring and the pressure adjustment unit is shorter than that in the conventional configuration. Therefore, the responsiveness of the fluid pressure is improved, and the pressing force can be quickly changed according to the unevenness of the surface of the substrate. As a result, the pressing force of the top ring against the substrate can be controlled more appropriately and accurately.

In a preferred aspect of the present reference example , a swing mechanism that swings the top ring about the support shaft is installed in the top ring head.
In a preferred aspect of the present reference example, the top ring head is detachably attached to the support shaft. If comprised in this way, while maintaining maintenance, the maintenance of an individual top ring head can be performed, without stopping the whole substrate processing process.

According to the above configuration, since the top ring head itself that is easy to access is provided with the pressure adjusting unit and the swinging mechanism, it is necessary to remove other adjacent equipment units during maintenance of the pressure adjusting unit and the swinging mechanism. There is no. In addition, the top ring, top ring head, pressure adjustment unit, swing mechanism, etc. can be configured as one module (unit), so replacement of bearings, motors, reducers, etc. that make up the swing mechanism is a module unit. Can be done. As a result, the apparatus downtime (that is, the time during which the device to be maintained is stopped) can be shortened. In a high-throughput substrate processing apparatus, shortening the downtime of the apparatus leads to a reduction in substrate processing costs. In this way, in this reference example, it is possible to perform maintenance of each device as a component while continuing the operation itself as much as possible. However, since the substrate processing can be continued and the replacement repair work is facilitated, it is possible to provide a substrate processing apparatus having a significantly improved service life.

Another reference example of the present invention includes a polishing unit having a plurality of polishing units for polishing a substrate, a transport mechanism for transporting the substrate between the plurality of polishing units, a cleaning unit for cleaning and drying the polished substrate, The substrate processing apparatus includes: a plurality of substrate transfer stages disposed on two travel axes having different heights; and the plurality of substrate transport stages along the two travel axes. A substrate processing apparatus comprising: a plurality of horizontal drive mechanisms that move in the horizontal direction; and a plurality of lift drive mechanisms that move the plurality of substrate transfer stages independently in the vertical direction.

  According to the above configuration, since the substrate can be transported in the horizontal direction and the top-bottom direction at the same time, the time required for transporting the substrate can be shortened. In addition, since the pusher that has been conventionally required can be omitted, the structure can be simplified and the maintenance of the transport mechanism can be easily performed. As a result, the downtime of the substrate processing apparatus can be shortened. Therefore, it is possible to provide a substrate processing apparatus that greatly improves maintainability and increases throughput.

A preferred embodiment of the present reference example includes a substrate path stage disposed on a traveling axis having a height different from that of the two traveling axes, and a horizontal drive mechanism that moves the substrate path stage in a horizontal direction along the traveling axis. And further comprising. According to such a configuration, a plurality of substrates can move in the horizontal direction at different heights at the same time, thereby improving the throughput.

Still another reference example of the present invention includes a polishing unit having a vertically movable top ring for holding a substrate, a transport mechanism having a vertically movable transport stage for transferring the top ring and the substrate, and the top ring. And a retainer ring station disposed between the transfer stage and the top ring, the top ring having a top ring body and a retainer ring movable up and down relative to the top ring body, The retainer ring station is a substrate processing apparatus having a plurality of push-up mechanisms for pushing up the retainer ring.

  According to the above configuration, since the retainer ring of the top ring is pushed up by the retainer ring station provided separately from the top ring and the transfer stage, the top ring and the transfer stage do not wait for each other when delivering the wafer. , Close to each other at approximately the same time, and spaced apart at approximately the same time. Accordingly, the substrate transfer time between the top ring and the transfer stage is shortened. In addition, the release operation of the substrate from the top ring is not hindered by the retainer ring, and the substrate can be reliably released from the top ring. Furthermore, when a plurality of polishing units are provided, the delivery time for reliably removing the substrate from the top ring and moving it to the transfer stage can be controlled reliably, so the transfer time of the substrate between the transfer stage and the top ring Can be leveled. As a result, the throughput of the entire substrate processing can be improved.

In a preferred aspect of the present reference example, the push-up mechanism includes a push-up pin that contacts the retainer ring and a spring that pushes the push-up pin upward.
In a preferred aspect of the present reference example, the retainer ring station includes a wear measuring device that measures a wear amount of the retainer ring while the push-up mechanism pushes up the retainer ring.
In a preferred aspect of this reference example, the wear measuring instrument is a linear motion that supports the contact member that contacts the lower surface of the retainer ring, a spring that pushes the contact member upward, and the contact member that is movable in the vertical direction. A guide and a displacement measuring device for measuring the displacement of the contact member are provided. According to such a configuration, the wear of the retainer ring can be measured without reducing the throughput of the entire substrate processing apparatus.

According to still another embodiment of the present invention, the top ring is moved to the substrate transfer position, the substrate is transferred to the transfer position by the transfer stage, the top ring is lowered, and the retainer ring of the top ring is pushed up. The retainer ring is lifted by the push-up mechanism by bringing it into contact, the transport stage is lifted while lowering the top ring, the substrate is transferred from the transport stage to the top ring, and the substrate is moved from the transport position to the polishing position. A substrate processing method characterized by moving and polishing a substrate.
According to this reference example , when delivering the wafer, the top ring and the transfer stage can approach each other at the same time and can be separated from each other at the same time without waiting for each other. Accordingly, the substrate transfer time between the top ring and the transfer stage is shortened. Further, the release operation of the substrate from the top ring is not hindered by the retainer ring, and the substrate can be reliably released from the top ring. Furthermore, when a plurality of polishing units are provided, the delivery time for reliably removing the substrate from the top ring and moving it to the transfer stage can be controlled reliably, so the transfer time of the substrate between the transfer stage and the top ring Can be leveled. As a result, the throughput of the entire substrate processing can be improved.

  According to the present invention, throughput in substrate processing can be improved. In addition, according to the present invention, a substrate processing apparatus that can be easily maintained is realized, and a constituent unit necessary for that purpose can be provided.

1 is a plan view showing an overall configuration of a substrate processing apparatus according to an embodiment of the present invention. It is a perspective view which shows a 1st grinding | polishing unit typically. It is sectional drawing which shows the structure of a top ring typically. It is sectional drawing which shows the other structural example of a top ring typically. It is sectional drawing for demonstrating the mechanism to rotate and rock | fluctuate a top ring. It is sectional drawing which shows typically the internal structure of a polishing table. It is a schematic diagram which shows the grinding | polishing table provided with the optical sensor. It is a schematic diagram which shows the polishing table provided with the microwave sensor. It is a perspective view which shows a dresser. It is a top view which shows a movement locus | trajectory when a dresser is dressing the polishing surface of a polishing pad. Fig.11 (a) is a perspective view which shows an atomizer, FIG.11 (b) is a schematic diagram which shows the lower part of an arm. FIG. 12A is a side view showing the internal structure of the atomizer, and FIG. 12B is a plan view showing the atomizer. FIG. 13A is a perspective view showing the polishing liquid supply nozzle, and FIG. 13B is an enlarged schematic view of the tip of the polishing liquid supply nozzle as viewed from below. It is a schematic diagram which shows the pure water supply piping of a grinding | polishing part. It is a perspective view which shows a 1st linear transporter typically. It is a schematic diagram which shows the height position of the conveyance stage of a 1st conveyance hand, the conveyance stage of a 2nd conveyance hand, the conveyance stage of a 3rd conveyance hand, and the conveyance stage of a 4th conveyance hand. It is a schematic diagram which shows the height position of the conveyance stage of a 2nd linear transporter. It is a perspective view explaining arrangement | positioning of the retainer ring station provided in the 2nd conveyance position, the 3rd conveyance position, the 6th conveyance position, and the 7th conveyance position, a conveyance stage, and a top ring. It is a perspective view which shows a retainer ring station and a conveyance stage. FIG. 20A is a side view showing the positional relationship between the retainer ring station and the top ring, and FIG. 20B is a plan view showing the positional relationship between the retainer ring station and the transfer stage. It is a perspective view which shows the state in which the top ring was mounted on the retainer ring station. FIG. 22A is a cross-sectional view showing the push-up mechanism, and FIG. 22B is a cross-sectional view showing the push-up mechanism when it comes into contact with the retainer ring. It is a perspective view which shows the retainer ring station provided with the abrasion measuring device which measures the abrasion loss of a retainer ring. It is an expanded sectional view which shows the abrasion measuring device shown in FIG. It is a side view of a retainer ring station and a top ring. It is a perspective view which shows the structure of a lifter. It is a perspective view which shows the structure of a swing transporter. FIG. 28A is a plan view showing the cleaning unit, and FIG. 28B is a side view showing the cleaning unit. It is a schematic diagram which shows an example of a washing line. It is a schematic diagram which shows an example of a washing line. It is a schematic diagram which shows an example of a washing line. It is a perspective view which shows a primary cleaning module. It is a longitudinal cross-sectional view which shows an upper side drying module. It is a top view which shows an upper side drying module. It is a top view of the base shown in FIG. 36 (a) is a plan view showing a part of the substrate support member and the base shown in FIG. 35, and FIG. 36 (b) is a cross-sectional view taken along line AA of FIG. ) Is a cross-sectional view taken along line BB of FIG. It is a schematic diagram for demonstrating arrangement | positioning of a 2nd magnet and a 3rd magnet, and is the figure seen from the axial direction of the board | substrate support member. FIG. 38A is a plan view showing a part of the substrate support member and the arm when the substrate support member is lifted by the lift mechanism, and FIG. 38B is a view of raising the substrate support member by the lift mechanism. 35 is a cross-sectional view taken along line AA of FIG. 35, and FIG. 38 (c) is a cross-sectional view taken along line CC of FIG. 38 (b). It is a schematic diagram which shows the IPA supply unit which supplies IPA vapor | steam to the nozzle of a drying module.

Embodiments of a substrate processing apparatus according to the present invention will be described below in detail with reference to the drawings. The same or corresponding components are denoted by the same reference numerals, and redundant description is omitted.
FIG. 1 is a plan view showing the overall configuration of a substrate processing apparatus according to an embodiment of the present invention. As shown in FIG. 1, the substrate processing apparatus includes a substantially rectangular housing 1, and the interior of the housing 1 is divided into a load / unload unit 2, a polishing unit 3 and a cleaning unit 4 by partition walls 1a and 1b. It is partitioned. The load / unload unit 2, the polishing unit 3, and the cleaning unit 4 are assembled independently and exhausted independently. The substrate processing apparatus has a control unit 5 that controls the substrate processing operation.

  The load / unload unit 2 includes two or more (four in this embodiment) front load units 20 on which wafer cassettes for stocking a large number of wafers (substrates) are placed. These front load portions 20 are arranged adjacent to the housing 1 and are arranged along the width direction (direction perpendicular to the longitudinal direction) of the substrate processing apparatus. The front load unit 20 can be equipped with an open cassette, a SMIF (Standard Manufacturing Interface) pod, or a FOUP (Front Opening Unified Pod). Here, SMIF and FOUP are sealed containers that can maintain an environment independent of the external space by accommodating a wafer cassette inside and covering with a partition wall.

  In addition, a traveling mechanism 21 is laid along the front load unit 20 in the load / unload unit 2, and two transfer robots that can move along the arrangement direction of the wafer cassettes on the traveling mechanism 21. A (loader) 22 is installed. The transfer robot 22 can access the wafer cassette mounted on the front load unit 20 by moving on the traveling mechanism 21. Each transfer robot 22 has two hands on the upper and lower sides. The upper hand is used to return the processed wafer to the wafer cassette, and the lower hand is used to take out the wafer before processing from the wafer cassette. Then, you can use the upper and lower hands properly. Furthermore, the lower hand of the transfer robot 22 is configured to be able to reverse the wafer by rotating around its axis.

  Since the load / unload unit 2 is an area where it is necessary to maintain the cleanest state, the pressure inside the load / unload unit 2 is higher than any of the outside of the substrate processing apparatus, the polishing unit 3 and the cleaning unit 4. Is always maintained. The polishing unit 3 is the most dirty region because slurry is used as the polishing liquid. Therefore, a negative pressure is formed inside the polishing unit 3, and the pressure is maintained lower than the internal pressure of the cleaning unit 4. The load / unload unit 2 is provided with a filter fan unit (not shown) having a clean air filter such as a HEPA filter, a ULPA filter, or a chemical filter. From the filter fan unit, particles, toxic vapor, Clean air from which toxic gases have been removed is constantly blowing out.

  The polishing unit 3 is a region where the wafer is polished (flattened), and includes a first polishing unit 3A, a second polishing unit 3B, a third polishing unit 3C, and a fourth polishing unit 3D. The first polishing unit 3A, the second polishing unit 3B, the third polishing unit 3C, and the fourth polishing unit 3D are arranged along the longitudinal direction of the substrate processing apparatus as shown in FIG.

  As shown in FIG. 1, the first polishing unit 3A includes a polishing table 30A to which a polishing pad 10 having a polishing surface is attached, and polishing while holding the wafer and pressing the wafer against the polishing pad 10 on the polishing table 30A. A top ring 31A for polishing, a polishing liquid supply nozzle 32A for supplying a polishing liquid or a dressing liquid (for example, pure water) to the polishing pad 10, and a dresser 33A for dressing the polishing surface of the polishing pad 10. And an atomizer 34A for spraying a mixed fluid of liquid (for example, pure water) and gas (for example, nitrogen gas) or a liquid (for example, pure water) to the polishing surface in the form of a mist.

  Similarly, the second polishing unit 3B includes a polishing table 30B to which the polishing pad 10 is attached, a top ring 31B, a polishing liquid supply nozzle 32B, a dresser 33B, and an atomizer 34B. 3C includes a polishing table 30C to which the polishing pad 10 is attached, a top ring 31C, a polishing liquid supply nozzle 32C, a dresser 33C, and an atomizer 34C. The fourth polishing unit 3D includes the polishing pad 10 An attached polishing table 30D, a top ring 31D, a polishing liquid supply nozzle 32D, a dresser 33D, and an atomizer 34D are provided.

Since the first polishing unit 3A, the second polishing unit 3B, the third polishing unit 3C, and the fourth polishing unit 3D have the same configuration, the first polishing unit 31A will be described below.
FIG. 2 is a perspective view schematically showing the first polishing unit 3A. The top ring 31 </ b> A is supported by the top ring shaft 36. A polishing pad 10 is affixed to the upper surface of the polishing table 30A, and the upper surface of the polishing pad 10 constitutes a polishing surface for polishing the wafer W. Note that fixed abrasive grains may be used in place of the polishing pad 10. The top ring 31 </ b> A and the polishing table 30 </ b> A are configured to rotate around their axial centers as indicated by arrows. The wafer W is held on the lower surface of the top ring 31A by vacuum suction. At the time of polishing, the polishing liquid is supplied from the polishing liquid supply nozzle 32A to the polishing surface of the polishing pad 10, and the wafer W to be polished is pressed against the polishing surface by the top ring 31A and polished.

  FIG. 3 is a cross-sectional view schematically showing the structure of the top ring 31A. The top ring 31 </ b> A is connected to the lower end of the top ring shaft 36 via a universal joint 37. The universal joint 37 is a ball joint that transmits the rotation of the top ring shaft 36 to the top ring 31A while allowing the top ring 31A and the top ring shaft 36 to tilt with each other. The top ring 31 </ b> A includes a substantially disk-shaped top ring main body 38 and a retainer ring 40 disposed at the lower part of the top ring main body 38. The top ring body 38 is made of a material having high strength and rigidity such as metal or ceramics. The retainer ring 40 is formed of a highly rigid resin material or ceramics. The retainer ring 40 may be formed integrally with the top ring body 38.

  In a space formed inside the top ring body 38 and the retainer ring 40, a circular elastic pad 42 that contacts the wafer W, an annular pressure sheet 43 made of an elastic film, and the elastic pad 42 are schematically held. A disk-shaped chucking plate 44 is accommodated. The upper peripheral end of the elastic pad 42 is held by a chucking plate 44, and four pressure chambers (airbags) P1, P2, P3, P4 are provided between the elastic pad 42 and the chucking plate 44. Yes. The pressure chambers P1, P2, P3, and P4 are formed by the elastic pad 42 and the chucking plate 44. Pressurized fluid such as pressurized air is supplied to the pressure chambers P1, P2, P3, and P4 via fluid passages 51, 52, 53, and 54, respectively, or evacuated. The central pressure chamber P1 is circular, and the other pressure chambers P2, P3, P4 are annular. These pressure chambers P1, P2, P3, and P4 are arranged concentrically.

  The internal pressures of the pressure chambers P1, P2, P3, and P4 can be changed independently from each other by a pressure adjusting unit, which will be described later. Thereby, four regions of the wafer W, that is, a central portion, an inner intermediate portion, The pressing force against the outer intermediate portion and the peripheral portion can be adjusted independently. Further, by raising and lowering the entire top ring 31A, the retainer ring 40 can be pressed against the polishing pad 10 with a predetermined pressing force. A pressure chamber P5 is formed between the chucking plate 44 and the top ring body 38. Pressurized fluid is supplied to the pressure chamber P5 via the fluid passage 55, or a vacuum is drawn. Yes. As a result, the entire chucking plate 44 and the elastic pad 42 can move in the vertical direction.

  The peripheral edge of the wafer W is surrounded by the retainer ring 40 so that the wafer W does not jump out of the top ring 31A during polishing. An opening (not shown) is formed in a portion of the elastic pad 42 constituting the pressure chamber P3, and the wafer W is attracted and held by the top ring 31A by forming a vacuum in the pressure chamber P3. ing. Further, the wafer W is released from the top ring 31A by supplying nitrogen gas, dry air, compressed air or the like to the pressure chamber P3.

  FIG. 4 is a cross-sectional view schematically showing another structural example of the top ring 31A. In this example, the chucking plate is not provided, and the elastic pad 42 is attached to the lower surface of the top ring body 38. Further, the pressure chamber P5 between the chucking plate and the top ring body 38 is not provided. Instead, an elastic bag 46 is disposed between the retainer ring 40 and the top ring body 38, and a pressure chamber P <b> 6 is formed inside the elastic bag 46. The retainer ring 40 can move up and down relatively with respect to the top ring body 38. A fluid passage 56 communicates with the pressure chamber P6, and a pressurized fluid such as pressurized air is supplied to the pressure chamber P6 through the fluid passage 56. The internal pressure of the pressure chamber P6 can be adjusted by a pressure adjusting unit described later. Therefore, the pressing force of the retainer ring 40 on the polishing pad 10 can be adjusted independently of the pressing force on the wafer W. Other configurations and operations are the same as those of the top ring shown in FIG. In this embodiment, any type of top ring shown in FIG. 3 or FIG. 4 can be used.

  FIG. 5 is a cross-sectional view for explaining a mechanism for rotating and swinging the top ring 31A. The top ring shaft (for example, spline shaft) 36 is rotatably supported by the top ring head 60. The top ring shaft 36 is connected to the rotation shaft of the motor M1 via pulleys 61 and 62 and a belt 63, and the top ring shaft 36 and the top ring 31A are rotated around the axis by the motor M1. The motor M1 is attached to the top of the top ring head 60. The top ring head 60 and the top ring shaft 36 are connected by an air cylinder 65 as a vertical drive source. The top ring shaft 36 and the top ring 31 </ b> A move up and down integrally by air (compressed gas) supplied to the air cylinder 65. Instead of the air cylinder 65, a mechanism having a ball screw and a servo motor may be used as the vertical drive source.

  The top ring head 60 is rotatably supported on a support shaft 67 via a bearing 72. The support shaft 67 is a fixed shaft and has a structure that does not rotate. The top ring head 60 is provided with a motor M2, and the relative position between the top ring head 60 and the motor M2 is fixed. The rotation shaft of the motor M2 is connected to a support shaft 67 through a rotation transmission mechanism (gear or the like) (not shown), and the top ring head 60 swings about the support shaft 67 by rotating the motor M2. (Swing). Therefore, the top ring 31A supported at the tip of the top ring head 60 moves between the polishing position above the polishing table 30A and the conveyance position on the side of the polishing table 30A by the swinging movement of the top ring head 60. In the present embodiment, the swing mechanism that swings the top ring 31A is constituted by the motor M2.

  A through hole (not shown) extending in the longitudinal direction is formed in the top ring shaft 36. The fluid passages 51, 52, 53, 54, 55, 56 of the top ring 31A described above are connected to a rotary joint 69 provided at the upper end of the top ring shaft 36 through this through hole. A fluid such as pressurized gas (clean air) or nitrogen gas is supplied to the top ring 31A via the rotary joint 69, and the gas is evacuated from the top ring 31A. A plurality of fluid pipes 70 communicating with the fluid passages 51, 52, 53, 54, 55, 56 (see FIGS. 3 and 4) are connected to the rotary joint 69, and these fluid pipes 70 are connected to the pressure adjusting unit 75. It is connected. A fluid pipe 71 that supplies pressurized air to the air cylinder 65 is also connected to the pressure adjustment unit 75.

  The pressure adjusting unit 75 includes an electropneumatic regulator that adjusts the pressure of the fluid supplied to the top ring 31A, pipes connected to the fluid pipes 70 and 71, air operated valves provided in these pipes, and these air operated valves. An electro-pneumatic regulator that adjusts the pressure of the air that serves as the operating source of this, an ejector that forms a vacuum in the top ring 31A, and the like, and these constitute a single block (unit). The pressure adjusting unit 75 is fixed to the top of the top ring head 60. The pressure of the pressurized gas supplied to the pressure chambers P1, P2, P3, P4, P5 (see FIG. 3) of the top ring 31A and the pressurized air supplied to the air cylinder 65 is the electric power of the pressure adjusting unit 75. Adjusted by an empty regulator. Similarly, a vacuum is formed in the airbags P1, P2, P3, and P4 of the top ring 31A and in the pressure chamber P5 between the chucking plate 44 and the top ring body 38 by the ejector of the pressure adjusting unit 75.

  As described above, since the electropneumatic regulator and the valve, which are pressure adjusting devices, are installed near the top ring 31A, the controllability of the pressure in the top ring 31A is improved. More specifically, since the distance between the electropneumatic regulator and the pressure chambers P1, P2, P3, P4, and P5 is short, the responsiveness to the pressure change command from the control unit 5 is improved. Similarly, since the ejector which is a vacuum source is also installed near the top ring 31A, the responsiveness when forming a vacuum in the top ring 31A is improved. Moreover, the back surface of the pressure adjustment part 75 can be utilized as a mounting base for electrical equipment, and a mounting frame that has been conventionally required can be dispensed with.

  The top ring head 60, the top ring 31A, the pressure adjusting unit 75, the top ring shaft 36, the motor M1, the motor M2, and the air cylinder 65 are configured as one module (hereinafter referred to as a top ring assembly). That is, the top ring shaft 36, the motor M 1, the motor M 2, the pressure adjustment unit 75, and the air cylinder 65 are attached to the top ring head 60. The top ring head 60 is configured to be removable from the support shaft 67. Therefore, by separating the top ring head 60 and the support shaft 67, the top ring assembly can be removed from the substrate processing apparatus. According to such a configuration, the maintainability of the support shaft 67 and the top ring head 60 can be improved. For example, when abnormal noise is generated from the bearing 72, the bearing 72 can be easily replaced, and there is no need to remove adjacent devices when replacing the motor M2 or the rotation transmission mechanism (reduction gear). .

  FIG. 6 is a cross-sectional view schematically showing the internal structure of the polishing table 30A. As shown in FIG. 6, a sensor 76 that detects the state of the film of the wafer W is embedded in the polishing table 30A. In this example, an eddy current sensor is used as the sensor 76. A signal from the sensor 76 is transmitted to the control unit 5, and a monitoring signal indicating the film thickness is generated by the control unit 5. Although the value of the monitoring signal (and sensor signal) does not indicate the film thickness itself, the value of the monitoring signal changes according to the film thickness. Therefore, it can be said that the monitoring signal is a signal indicating the film thickness of the wafer W.

  The control unit 5 determines the internal pressure of each pressure chamber P1, P2, P3, P4 based on the monitoring signal, and the pressure so that the determined internal pressure is formed in each pressure chamber P1, P2, P3, P4. A command is issued to the adjustment unit 75. The control unit 5 functions as a pressure control unit for operating the internal pressures of the pressure chambers P1, P2, P3, and P4 based on the monitoring signal and as an end point detection unit that detects a polishing end point.

  Similar to the first polishing unit 3A, the sensor 76 is also provided on the polishing tables of the second polishing unit 3B, the third polishing unit 3C, and the fourth polishing unit 3D. The controller 5 generates a monitoring signal from signals sent from the sensors 76 of the polishing units 3A to 3D, and monitors the progress of wafer polishing in the polishing units 3A to 3D. When a plurality of wafers are polished by the polishing units 3A to 3D, the control unit 5 monitors a monitoring signal indicating the film thickness of the wafer during polishing, and based on these monitoring signals, the polishing units 3A to 3D The pressing forces of the top rings 31 </ b> A to 31 </ b> D are controlled so that the polishing times are substantially the same. Thus, the polishing time in the polishing units 3A to 3D can be leveled by adjusting the pressing forces of the top rings 31A to 31D during polishing based on the monitoring signal.

  The wafer W may be polished by any one of the first polishing unit 3A, the second polishing unit 3B, the third polishing unit 3C, and the fourth polishing unit 3D, or selected in advance from these polishing units 3A to 3D. You may grind | polish continuously with a some grinding | polishing unit. For example, the wafer W may be polished in the order of the first polishing unit 3A → the second polishing unit 3B, or the wafer W may be polished in the order of the third polishing unit 3C → the fourth polishing unit 3D. Further, the wafer W may be polished in the order of the first polishing unit 3A → the second polishing unit 3B → the third polishing unit 3C → the fourth polishing unit 3D. In any case, the throughput can be improved by leveling all the polishing times of the polishing units 3A to 3D.

  The eddy current sensor is preferably used when the wafer film is a metal film. When the wafer film is a light-transmitting film such as an oxide film, an optical sensor can be used as the sensor 76. Alternatively, a microwave sensor may be used as the sensor 76. The microwave sensor can be used for both metal films and non-metal films. Hereinafter, examples of the optical sensor and the microwave sensor will be described.

  FIG. 7 is a schematic diagram showing a polishing table provided with an optical sensor. As shown in FIG. 7, an optical sensor 76 that detects the state of the film of the wafer W is embedded in the polishing table 30A. The sensor 76 irradiates the wafer W with light, and detects the film state (film thickness, etc.) of the wafer W from the intensity (reflection intensity or reflectance) of the reflected light from the wafer W.

  The polishing pad 10 is provided with a light transmitting portion 77 for transmitting light from the sensor 76. The light transmitting portion 77 is made of a material having a high transmittance, and is made of, for example, non-foamed polyurethane. Alternatively, the translucent portion 77 may be configured by providing a through hole in the polishing pad 10 and flowing a transparent liquid from below while the through hole is blocked by the wafer W. The translucent part 77 is disposed at a position passing through the center of the wafer W held by the top ring 31A.

  As shown in FIG. 7, the sensor 76 receives a light source 78a, a light emitting optical fiber 78b as a light emitting unit for irradiating the surface to be polished of the wafer W with light from the light source 78a, and reflected light from the surface to be polished. A light receiving optical fiber 78c as a light receiving unit, a spectroscope that splits light received by the light receiving optical fiber 78c, and a plurality of light receiving elements that store therein the light dispersed by the spectroscope as electrical information. Instrument unit 78d, an operation control unit 78e for controlling the turning on and off of the light source 78a, the timing of reading start of the light receiving elements in the spectroscope unit 78d, and a power source 78f for supplying power to the operation control unit 78e. ing. Note that power is supplied to the light source 78a and the spectroscope unit 78d via the operation control unit 78e.

  The light emitting end of the light emitting optical fiber 78 b and the light receiving end of the light receiving optical fiber 78 c are configured to be substantially perpendicular to the surface to be polished of the wafer W. For example, a 128-element photodiode array can be used as the light receiving element in the spectroscope unit 78d. The spectroscope unit 78d is connected to the operation control unit 78e. Information from the light receiving element in the spectroscope unit 78d is sent to the operation controller 78e, and spectrum data of reflected light is generated based on this information. In other words, the operation control unit 78e reads the electrical information accumulated in the light receiving element and generates the spectrum data of the reflected light. This spectral data indicates the intensity of the reflected light decomposed according to the wavelength, and varies depending on the film thickness.

  The operation control unit 78e is connected to the control unit 5 described above. In this way, the spectrum data generated by the operation control unit 78e is transmitted to the control unit 5. The control unit 5 calculates a characteristic value associated with the film thickness of the wafer W based on the spectrum data received from the operation control unit 78e, and uses this as a monitoring signal.

  FIG. 8 is a schematic view showing a polishing table provided with a microwave sensor. The sensor 76 includes an antenna 80a that irradiates microwaves toward the surface to be polished of the wafer W, a sensor main body 80b that supplies the microwaves to the antenna 80a, and a waveguide 81 that connects the antenna 80a and the sensor main body 80b. It has. The antenna 80a is embedded in the polishing table 30A and is disposed so as to face the center position of the wafer W held by the top ring 31A.

  The sensor body 80b includes a microwave source 80c that generates a microwave and supplies the microwave to the antenna 80a, a microwave (incident wave) generated by the microwave source 80c, and a microwave (reflected wave) reflected from the surface of the wafer W. ), And a detector 80e that receives the reflected wave separated by the separator 80d and detects the amplitude and phase of the reflected wave. As the separator 80d, a directional coupler is preferably used.

  The antenna 80a is connected to the separator 80d through the waveguide 81. The microwave source 80c is connected to the separator 80d, and the microwave generated by the microwave source 80c is supplied to the antenna 80a via the separator 80d and the waveguide 81. The microwave is irradiated from the antenna 80 a toward the wafer W, passes through (through) the polishing pad 10, and reaches the wafer W. The reflected wave from the wafer W passes through the polishing pad 10 again and is received by the antenna 80a.

  The reflected wave is sent from the antenna 80a to the separator 80d via the waveguide 81, and the incident wave and the reflected wave are separated by the separator 80d. The reflected wave separated by the separator 80d is transmitted to the detection unit 80e. The detector 80e detects the amplitude and phase of the reflected wave. The amplitude of the reflected wave is detected as electric power (dbm or W) or voltage (V), and the phase of the reflected wave is detected by a phase measuring instrument (not shown) built in the detector 80e. The amplitude and phase of the reflected wave detected by the detection unit 80e are sent to the control unit 5, where the film thickness of the metal film or non-metal film of the wafer W is analyzed based on the amplitude and phase of the reflected wave. The analyzed value is monitored by the control unit 5 as a monitoring signal.

  FIG. 9 is a perspective view showing a dresser 33A that can be used as an embodiment of the present invention. As shown in FIG. 9, the dresser 33 </ b> A includes a dresser arm 85, a dressing member 86 that is rotatably attached to the tip of the dresser arm 85, a swing shaft 88 that is connected to the other end of the dresser arm 85, and a swinger. A motor 89 is provided as a drive mechanism that swings (swings) the dresser arm 85 about the moving shaft 88. The dressing member 86 has a circular dressing surface, and hard particles are fixed to the dressing surface. Examples of the hard particles include diamond particles and ceramic particles. A motor (not shown) is built in the dresser arm 85, and the dressing member 86 is rotated by this motor. The swing shaft 88 is connected to a lifting mechanism (not shown), and the dressing member 86 presses the polishing surface of the polishing pad 10 when the dresser arm 85 is lowered by the lifting mechanism.

  FIG. 10 is a plan view showing a movement locus when the dresser 33A is dressing the polishing surface of the polishing pad 10. FIG. As shown in FIG. 10, the dresser arm 85 is longer than the radius of the polishing pad 10, and the swing shaft 88 is located on the radially outer side of the polishing pad 10. When dressing the polishing surface of the polishing pad 10, the polishing pad 10 is rotated, the dressing member 86 is rotated by a motor, the dresser arm 85 is lowered by an elevating mechanism, and the dressing member 86 is rotated. Make sliding contact with the polished surface. In this state, the dresser arm 85 is swung (swinged) by the motor 89. During dressing of the polishing pad 10, pure water as a dressing liquid is supplied from the polishing liquid supply nozzle 32 </ b> A to the polishing surface of the polishing pad 10. As the dresser arm 85 swings, the dressing member 86 located at the tip of the dresser arm 85 moves across the center of the polishing surface from end to end of the polishing surface of the polishing pad 10 as shown in FIG. be able to. By this swinging operation, the dressing member 86 can dress the entire polishing surface of the polishing pad 10 including its center, and the dressing effect on the polishing surface can be remarkably enhanced. Therefore, the entire polishing surface can be dressed uniformly, and a flat polishing surface can be obtained.

  After the dressing is completed, the dresser arm 85 moves to the standby position A1 on the side of the polishing table 30A as shown in FIG. During maintenance of the dresser 33A, the dresser arm 85 moves to a maintenance position A4 that is substantially opposite to the standby position A1. As shown in FIG. 10, during dressing, the dresser arm 85 may be swung between the position A2 at the end of the polishing surface and the position A3 at the center of the polishing surface. . According to such an operation, the dressing operation can be performed quickly, and the dressing operation can be reliably terminated.

  In the above-described example, the dresser arm 85 and the dressing member 86 are integrally moved up and down by the lifting mechanism connected to the swing shaft 88. However, the lifting mechanism is built in the dresser arm 85, and the dressing member is provided by this lifting mechanism. 86 may be moved up and down. Furthermore, in another modified example, a first lifting mechanism for moving the swing shaft 88 up and down can be provided, and a second lifting mechanism for moving the dressing member 86 up and down can be incorporated in the dresser arm 85. In this case, the dresser arm 85 can be lowered by the first lifting mechanism, and the dressing member 86 can be lowered by the second lifting mechanism when the dresser arm 85 reaches a predetermined height position. According to such a configuration, the pressing force on the polishing surface during dressing and the height of the dressing member 86 can be accurately adjusted.

  FIG. 11A is a perspective view showing the atomizer 34A. The atomizer 34 </ b> A includes an arm 90 having one or a plurality of injection holes in the lower part, a fluid flow path 91 connected to the arm 90, and a swing shaft 94 that supports the arm 90. FIG. 11B is a schematic diagram showing the lower part of the arm 90. In the example shown in FIG. 11B, a plurality of injection holes 90 a are formed at equal intervals in the lower part of the arm 90. The fluid flow path 91 can be composed of a tube, a pipe, or a combination thereof.

  FIG. 12A is a side view showing the internal structure of the atomizer 34A, and FIG. 12B is a plan view showing the atomizer 34A. The opening end of the fluid channel 91 is connected to a fluid supply pipe (not shown), and fluid is supplied to the fluid channel 91 from the fluid supply pipe. Examples of the fluid used include a liquid (for example, pure water) or a mixed fluid of liquid and gas (for example, a mixed fluid of pure water and nitrogen gas). The fluid flow path 91 communicates with the injection hole 90a of the arm 90, and the fluid is sprayed on the polishing surface of the polishing pad 10 from the injection hole 90a.

  As shown by the dotted lines in FIGS. 11A and 12B, the arm 90 can pivot between the cleaning position and the retracted position about the swing shaft 94. The movable angle of the arm 90 is about 90 °. Normally, the arm 90 is at the cleaning position and is disposed along the radial direction of the polishing surface of the polishing pad 10 as shown in FIG. During maintenance such as replacement of the polishing pad 10, the arm 90 is manually moved to the retracted position. Therefore, it is not necessary to remove the arm 90 during maintenance, and maintainability can be improved. A rotation mechanism may be connected to the swing shaft 94, and the arm 90 may be turned by this rotation mechanism.

  As shown in FIG. 12B, two reinforcing members 96 and 96 having different shapes are provided on both side surfaces of the arm 90. By providing these reinforcing members 96, 96, when the arm 90 pivots between the cleaning position and the retracted position, the axial center of the arm 90 is not greatly shaken, and the atomizing operation is effective. Can be done automatically. In addition, the atomizer 34A includes a lever 95 for fixing a turning position of the arm 90 (an angle range in which the arm 90 can turn). That is, by operating the lever 95, the angle at which the arm 90 can turn can be adjusted according to the conditions. When the lever 95 is turned, the arm 90 can freely rotate, and the arm 90 is manually moved between the cleaning position and the retracted position. When the lever 95 is tightened, the position of the arm 90 is fixed at either the cleaning position or the retracted position.

  The atomizer arm 90 may be foldable. Specifically, the arm 90 may be composed of at least two arm members connected by a joint. In this case, the angle formed by the arm members when folded is 1 ° to 45 °, preferably 5 ° to 30 °. If the angle formed by the arm members is greater than 45 °, the space occupied by the arm 90 is increased. If the angle is less than 1 °, the width of the arm 90 must be reduced, and the mechanical strength is reduced. In this example, the arm 90 may be configured not to rotate around the swing shaft 94. At the time of maintenance such as replacement of the polishing pad 10, the arm 90 can be folded so that the atomizer does not interfere with the maintenance work. As another modification, the arm 90 of the atomizer can be configured to be extendable and contractible. In this example as well, the atomizer does not get in the way by contracting the arm 90 during maintenance.

  The purpose of providing the atomizer 34A is to wash away polishing debris and abrasive grains remaining on the polishing surface of the polishing pad 10 with a high-pressure fluid. A more preferable dressing, that is, regeneration of the polishing surface, can be achieved by purifying the polishing surface by the fluid pressure of the atomizer 34A and sharpening the polishing surface by the dresser 33A which is mechanical contact. Usually, after the dressing by a contact type dresser (diamond dresser or the like), the polished surface is often regenerated by an atomizer.

  FIG. 13A is a perspective view showing the polishing liquid supply nozzle 32A, and FIG. 13B is an enlarged schematic view of the front end of the polishing liquid supply nozzle 32A as viewed from below. As shown in FIGS. 13 and 13B, the polishing liquid supply nozzle 32A includes a plurality of tubes 100 for supplying a polishing liquid such as pure water or slurry to the polishing surface of the polishing pad 10, and the plurality of tubes. A pipe arm 101 that covers 100 and a swing shaft 102 that supports the pipe arm 101 are provided. The plurality of tubes 100 are usually composed of a pure water supply tube for supplying pure water and a plurality of slurry supply tubes for supplying different types of slurry. As the plurality of tubes 100, for example, from two to four (for example, three) slurry supply tubes through which slurry passes and one or two pure water supply tubes through which pure water passes. Can be configured.

  The plurality of tubes 100 extend through the inside of the pipe arm 101 to the tip of the pipe arm 101, and the pipe arm 101 covers almost the entire tube 100. A reinforcing material 103 is fixed to the tip of the pipe arm 101. The tip of the tube 100 is located above the polishing pad 10, and a polishing liquid is supplied from the tube 100 onto the polishing surface of the polishing pad 10. The arrow shown in FIG. 13A represents the polishing liquid supplied to the polishing surface. The rocking shaft 102 is connected to a rotation mechanism (such as a motor) (not shown), and by rotating the rocking shaft 102, it is possible to supply the polishing liquid to a desired position on the polishing surface. During maintenance such as replacement of the polishing pad 10, the pipe arm 101 is swung by the rotating mechanism about the swinging shaft 102 and moved to a retracted position on the side of the polishing table 30 </ b> A.

  As described above, since the plurality of tubes 100 are almost entirely covered by the pipe arm 101, the surface area of the entire nozzle 32A is smaller than when the plurality of tubes 100 are not covered by the pipe arm 101. be able to. Therefore, the area to which a part of the slurry swollen during the polishing or atomizer treatment adheres becomes small. As a result, an adverse effect on the polishing process due to the falling of the attached slurry is prevented, and the cleaning liquid supply nozzle 32A can be easily cleaned.

  FIG. 14 is a schematic diagram showing a pure water supply pipe of the polishing unit 3. In this substrate processing apparatus, the first polishing unit 3A and the second polishing unit 3B constitute the first polishing unit 3a as one unit, and the third polishing unit 3C and the fourth polishing unit 3D are the first unit. 2 constitutes a polishing section 3b. The 1st grinding | polishing part 3a and the 2nd grinding | polishing part 3b are comprised so that division | segmentation is mutually possible. As described above, the polishing unit 3 uses various fluids such as pure water, air, and nitrogen gas. For example, as shown in FIG. 14, pure water (DIW) is supplied from a pure water supply source (not shown) to the pure water supply pipe 110 of the substrate processing apparatus. The pure water supply pipe 110 extends through the polishing units 3A, 3B, 3C, 3D of the polishing unit 3 and is connected to a distribution control unit 113 provided in each of the polishing units 3A, 3B, 3C, 3D.

  The pure water supply pipe 110 is divided between the first polishing section 3a and the second polishing section 3b, and the ends of the divided pure water supply pipe 110 are connected by a connection mechanism (not shown). Examples of pure water used in each polishing unit include cleaning of the top ring (for example, cleaning of the outer peripheral side surface of the top ring, cleaning of the substrate holding surface, cleaning of the retainer ring), cleaning of the wafer transfer hand (for example, Cleaning of conveyance hands of first and second linear transporters described later), polishing of polished wafer, dressing of polishing pad, cleaning of dresser (for example, cleaning of dressing member), cleaning of dresser arm, supply of polishing liquid Nozzle cleaning and polishing pad cleaning with an atomizer may be mentioned.

  Pure water flows into each distribution control unit 113 through the pure water supply pipe 110 and is distributed to each use point by each distribution control unit 113. The use point is a place where pure water such as the above-described nozzle for top ring cleaning and nozzle for dresser cleaning is used. The pure water is supplied from the distribution control unit 113 to a terminal device such as a cleaning nozzle (for example, the above-described top ring cleaning nozzle or dresser cleaning nozzle) provided in the polishing unit. For example, pure water having a flow rate adjusted by the distribution control unit 113 for each polishing unit is supplied to the pure water supply tube 100 (see FIG. 13A) of the polishing liquid supply nozzle described above. As described above, since the distribution control unit 113 is arranged for each polishing unit, the number of pipes can be reduced as compared with the conventional structure in which each polishing unit is supplied from one header via a plurality of pipes. it can. This also means that the number of connecting mechanisms for connecting the pipes between the first polishing unit 3a and the second polishing unit 3b is reduced, so that the structure becomes simple and there is a risk of leakage of pure water. Reduced. Since the atomizer requires a large amount of pure water, it is preferable to provide a pure water supply pipe 112 dedicated to the atomizer as shown in FIG.

  Each distribution control unit 113 includes a valve box 113a communicating with a use point such as a nozzle for cleaning a top ring (not shown) and a pure water supply tube 100 (see FIG. 13A), and an upstream side of the valve box 113a. And a flow rate regulator 113c provided on the upstream side of the pressure gauge 113b. The valve box 113a has a plurality of pipes that communicate with the use points, and valves that are respectively provided on these pipes.

  The pressure gauge 113b measures the pressure of pure water sent to the valve box 113a, and the flow regulator 113c adjusts the flow rate of pure water so that the measured value of the pressure gauge 113b is maintained at a predetermined value. As described above, since the flow rate of pure water is controlled in each polishing unit, the influence of the use of pure water between the polishing units is reduced, and stable supply of pure water is possible. Therefore, the problem in the conventional structure that the flow rate of pure water in one polishing unit becomes unstable due to the influence of the use of pure water in another polishing unit can be solved. In the example shown in FIG. 14, the flow rate regulator 113c is provided in each polishing unit. However, one flow rate regulator 113c may be provided for each of the two polishing units. For example, a pair of pressure gauges 113b and a flow rate regulator 113c are provided upstream of two valve boxes 113a provided in the polishing units 3A and 3B, respectively. Similarly, two valves provided in the polishing units 3C and 3D, respectively. A set of pressure gauges 113b and a flow rate regulator 113c may be provided upstream of the box 113a.

  In the example shown in FIG. 14, a pure water dedicated to the atomizers 34A, 34B, 34C, and 34D is used separately from the use point pure water supply pipe 110 such as a top ring cleaning nozzle (not shown) and the pure water supply tube 100. A water supply pipe 112 is provided. The pure water supply pipe 112 is connected to the atomizers 34A, 34B, 34C, 34D, and a flow rate control unit 114 is provided on the upstream side of the atomizers 34A, 34B, 34C, 34D. The flow rate control unit 114 is configured to adjust the flow rate of pure water supplied from the pure water supply pipe 112 and to send the adjusted pure water to the atomizer.

  Each flow control unit 114 includes a valve, a pressure gauge, and a flow regulator similarly to the distribution control unit 113 described above, and the arrangement thereof is the same as the arrangement in the distribution control unit 113. The control unit 5 controls the operation of the flow rate regulator of the flow rate control unit 114 so that pure water having a predetermined flow rate is supplied to each atomizer based on the measurement value of the pressure gauge of the flow rate control unit 114.

  As shown in FIG. 14, the pure water supply pipe 110 and the pure water supply pipe 112 are each independently connected to a pure water supply source, and an independent pure water supply path is secured. With such an arrangement, it is possible to prevent the use of pure water in the atomizer from affecting the flow rate of pure water at other use points.

  14 illustrates the pure water supply pipe 110 that supplies pure water, the arrangement of the piping and distribution control unit shown in FIG. 14 is provided in a supply pipe for other fluids such as air, nitrogen gas, and slurry. Is also applicable. For example, a plurality of slurry supply pipes for transferring a plurality of types of slurry can be provided, and a distribution control unit connected to these slurry supply pipes can be provided for each polishing unit. Each distribution control unit supplies the slurry selected according to the polishing process to the above-described polishing liquid supply nozzle (see FIG. 13A). Since the distribution control unit is provided for each polishing unit, the type of slurry supplied to the polishing liquid supply nozzle can be changed for each polishing unit. Furthermore, the flow rate of the slurry supplied to the polishing liquid supply nozzle can be adjusted by the distribution control unit.

  Next, a transport mechanism for transporting the wafer will be described. As shown in FIG. 1, a first linear transporter 6 is disposed adjacent to the first polishing unit 3A and the second polishing unit 3B. The first linear transporter 6 has four transfer positions along the direction in which the polishing units 3A and 3B are arranged (first transfer position TP1, second transfer position TP2, and third transfer in order from the load / unload unit side). This is a mechanism for transferring the wafer between the position TP3 and the fourth transfer position TP4.

  Further, the second linear transporter 7 is disposed adjacent to the third polishing unit 3C and the fourth polishing unit 3D. The second linear transporter 7 has three transfer positions (a fifth transfer position TP5, a sixth transfer position TP6, and a seventh transfer in order from the load / unload unit side) along the direction in which the polishing units 3C and 3D are arranged. This is a mechanism for transporting the wafer between positions TP7).

  The wafer is transferred to the polishing units 3A and 3B by the first linear transporter 6. As described above, the top ring 31A of the first polishing unit 3A moves between the polishing position and the second transport position TP2 by the swing operation of the top ring head 60. Therefore, the wafer is transferred to the top ring 31A at the second transfer position TP2. Similarly, the top ring 31B of the second polishing unit 3B moves between the polishing position and the third transfer position TP3, and the delivery of the wafer to the top ring 31B is performed at the third transfer position TP3. The top ring 31C of the third polishing unit 3C moves between the polishing position and the sixth transfer position TP6, and the delivery of the wafer to the top ring 31C is performed at the sixth transfer position TP6. The top ring 31D of the fourth polishing unit 3D moves between the polishing position and the seventh transfer position TP7, and the delivery of the wafer to the top ring 31D is performed at the seventh transfer position TP7.

  A lifter 11 for receiving a wafer from the transfer robot 22 is disposed at the first transfer position TP1. The wafer is transferred from the transfer robot 22 to the first linear transporter 6 through the lifter 11. A shutter (not shown) is provided between the lifter 11 and the transfer robot 22 in the partition wall 1a. When the wafer is transferred, the shutter is opened so that the wafer is transferred from the transfer robot 22 to the lifter 11. It has become. A swing transporter 12 is arranged between the first linear transporter 6, the second linear transporter 7, and the cleaning unit 4. The swing transporter 12 has a hand that can move between the fourth transfer position TP4 and the fifth transfer position TP5, and transfers the wafer from the first linear transporter 6 to the second linear transporter 7. Is performed by the swing transporter 12. The wafer is transferred to the third polishing unit 3C and / or the fourth polishing unit 3D by the second linear transporter 7. The wafer polished by the polishing unit 3 is transferred to the cleaning unit 4 via the swing transporter 12.

Hereinafter, the structures of the first linear transporter 6, the second linear transporter 7, the lifter 11, and the swing transporter 12 will be described.
FIG. 15 is a perspective view schematically showing the first linear transporter 6. The first linear transporter 6 includes first, second, third, and fourth transfer hands 121, 122, 123, having transfer stages (substrate transfer stages) 121a, 122a, 123a, and 124a on which wafers are placed. 124, three elevating drive mechanisms (for example, a motor drive mechanism or an air cylinder using a ball screw) 130A, 130B, and 130C that move the second, third, and fourth transport hands 122, 123, and 124 up and down, Three linear guides 132A, 132B, and 132C for supporting the first, second, third, and fourth transport hands 121, 122, 123, and 124 movably in the horizontal direction, and the first, second, third, and fourth Three horizontal drive mechanisms 134A, 134B, and 134C that drive the transport hands 121, 122, 123, and 124 in the horizontal direction are provided. In the present embodiment, the horizontal drive mechanisms 134A, 134B, and 134C each include a pair of pulleys 136, a belt 137 hung on the pulleys 136, and a servo motor 138 that rotates any one of the pair of pulleys. Have.

  A plurality of pins are provided on the upper surfaces of the transfer stages 121a, 122a, 123a, and 124a, and the wafer is placed on these pins. Each of the transfer stages 121a, 122a, 123a, and 124a includes a sensor (not shown) that detects the presence / absence of a wafer using a transmission sensor or the like, and the wafers on the transfer stages 121a, 122a, 123a, and 124a are detected. The presence or absence can be detected.

  The first transport hand 121 is supported by the first linear guide 132A, and is driven by the first horizontal drive mechanism 134A to move between the first transport position TP1 and the fourth transport position TP4. The first transport hand 121 is a pass hand for receiving a wafer from the lifter 11 and transferring it to the second linear transporter 7. Therefore, the first transfer hand 121 is used when the wafer is polished by the third polishing unit 3C and the fourth polishing unit 3D without being polished by the first polishing unit 3A and the second polishing unit 3B. The first transport hand 121 is not provided with a lifting drive mechanism, and the transport stage (substrate path stage) 121a of the first transport hand 121 is movable only in the horizontal direction.

  The second transport hand 122 is supported by the second linear guide 132B and is driven by the second horizontal drive mechanism 134B to move between the first transport position TP1 and the second transport position TP2. The second transfer hand 122 functions as an access hand for transferring the wafer from the lifter 11 to the first polishing unit 3A. That is, the second transfer hand 122 moves to the first transfer position TP1 and receives the wafer from the lifter 11 here. Then, the second transfer hand 122 moves again to the second transfer position TP2, and transfers the wafer on the transfer stage 122a to the top ring 31A. A first elevating drive mechanism 130A is coupled to the second transport hand 122, and these move together in the horizontal direction. When the wafer on the transfer stage 122a is transferred to the top ring 31A, the second transfer hand 122 is driven by the first lift drive mechanism 130A to rise, and after passing the wafer to the top ring 31A, the first lift drive mechanism 130A. Driven to descend.

  A plurality of (three in the drawing) access guides 140 that are engaged with the lower end of the outer peripheral edge of the top ring 31A (the lower end of the retainer ring 40) are provided on the upper surface of the transfer stage 122a. The inside of these access guides 140 has a tapered surface, and when the transport stage 122a moves up and accesses the top ring 31A, the top ring 31A is guided by these access guides 140, and the top ring 31A and the transport stage 122a Engage each other. By this engagement, centering is performed between the top ring 31A and the transfer stage 122a (ie, the wafer). The access guide 140 is also provided on the transfer stages 123a and 124a of the third and fourth transfer hands 123 and 124 in the same manner.

  The third transport hand 123 and the fourth transport hand 124 are supported by the third linear guide 132C. The third transport hand 123 and the fourth transport hand 124 are connected to each other by an air cylinder 142, and these are driven by the third horizontal drive mechanism 134C to move integrally in the horizontal direction. The air cylinder 142 functions as an interval adjusting mechanism that adjusts the interval between the transfer stage 123 a of the third transfer hand 123 and the transfer stage 124 a of the fourth transfer hand 124. The reason why the air cylinder (interval adjustment mechanism) 142 is provided is that the interval between the first transfer position TP1 and the second transfer position TP2 and the interval between the second transfer position TP2 and the third transfer position TP3 may be different. Because. The air cylinder 142 can perform an interval adjustment operation while the third transport hand 123 and the fourth transport hand 124 are moving.

  A second lifting drive mechanism 130B is connected to the third transport hand 123, and a third lifting drive mechanism 130C is connected to the fourth transport hand 124. The third transport hand 123 and the fourth transport hand 124 are independent. And can be moved up and down. The third transport hand 123 moves between the first transport position TP1, the second transport position TP2, and the third transport position TP3, and at the same time, the fourth transport hand 124 has the second transport position TP2, the third transport position TP3, It moves between the fourth transport positions TP4.

  The third transfer hand 123 functions as an access hand for transferring the wafer from the lifter 11 to the second polishing unit 3B. That is, the third transfer hand 123 moves to the first transfer position TP1, receives the wafer from the lifter 11, moves further to the third transfer position TP3, and passes the wafer on the transfer stage 123a to the top ring 31B. Operate. The third transfer hand 123 also functions as an access hand for transferring the wafer polished by the first polishing unit 3A to the second polishing unit 3B. That is, the third transfer hand 123 moves to the second transfer position TP2, where it receives the wafer from the top ring 31A, further moves to the third transfer position TP3, and moves the wafer on the transfer stage 123a to the top ring 31B. Works to pass. When the wafer is transferred between the transfer stage 123a and the top ring 31A or the top ring 31B, the third transfer hand 123 is driven by the second lifting / lowering drive mechanism 130B and is lifted, and after the transfer of the wafer is finished. Is driven by the second elevating drive mechanism 130B, and the third transport hand 123 is lowered.

  The fourth transfer hand 124 functions as an access hand for transferring the wafer polished by the first polishing unit 3A or the second polishing unit 3B to the swing transporter 12. That is, the fourth transfer hand 124 moves to the second transfer position TP2 or the third transfer position TP3, receives the polished wafer from the top ring 31A or the top ring 31B, and then moves to the fourth transfer position TP4. When the wafer is received from the top ring 31A or the top ring 31B, the fourth transport hand 124 is driven and lifted by the third lifting / lowering driving mechanism 130C. After receiving the wafer, the fourth transport hand 124 is driven and lowered by the third lifting / lowering driving mechanism 130C. To do.

  FIG. 16 shows the height positions of the transfer stage 121a of the first transfer hand 121, the transfer stage 122a of the second transfer hand 122, the transfer stage 123a of the third transfer hand 123, and the transfer stage 124a of the fourth transfer hand 124. It is a schematic diagram. As shown in FIG. 16, the four transfer stages 121a to 124c move along three travel axes having different heights. That is, the transport stage 121a moves along the lowest first travel axis, the transport stage 123a and the transport stage 124a move along the highest third travel axis, and the transport stage 122a moves along the first travel axis. It moves along the second travel axis located between the travel axis and the third travel axis. Accordingly, the transfer stages 121a, 122a, 123a, and 124c can move in the horizontal direction without contacting each other.

  With this arrangement, the first linear transporter 6 can transport the wafer received from the lifter 11 to either the first polishing unit 3A or the second polishing unit 3B. For example, while the wafer is conveyed to the first polishing unit 3A and the wafer is being polished by the first polishing unit 3A, the next wafer can be directly sent to the second polishing unit 3B for polishing. Therefore, the throughput is improved. Further, the wafer polished by the first polishing unit 3A can be transported to the second polishing unit 3B, and the wafer can be further polished by the second polishing unit 3B. The second, third, and fourth transport hands 122, 123, and 124 can move in the vertical direction while moving in the horizontal direction. For example, after the second transfer hand 122 receives the wafer at the first transfer position TP1, it rises while moving to the second transfer position TP2, and after arriving at the second transfer position TP2, the wafer is quickly transferred to the top ring 31A. Can be passed to. Such an operation can be similarly performed by the third and fourth transport hands 123 and 124. Therefore, the wafer transfer time is shortened, and the throughput of the substrate processing apparatus can be improved. Further, since the transfer stage 121a of the first transfer hand 121 is at a lower position than the other transfer hands, the wafer is placed at the fourth transfer position TP4 even when the other transfer hand is accessing the top ring. Can be transported. Thus, the provision of the three travel axes increases the degree of freedom of wafer transfer.

  The second linear transporter 7 has basically the same configuration as the first linear transporter 6, but is different from the first linear transporter 6 in that it does not include an element corresponding to the first transport hand 121. Is different. FIG. 17 is a schematic diagram showing the height position of the transport stage of the second linear transporter 7. Since the configuration of the second linear transporter 7 not specifically described is the same as that of the first linear transporter 6, the redundant description is omitted. The second linear transporter 7 includes a fifth transport hand 125, a sixth transport hand 126, and a seventh transport hand 127. The fifth transfer hand 125, the sixth transfer hand 126, and the seventh transfer hand 127 have transfer stages 125a, 126a, and 127a on which wafers are placed, respectively.

  The fifth transport hand 125 and the sixth transport hand 126 are connected to each other by an air cylinder 142 as an interval adjusting mechanism, whereby the fifth transport hand 125 and the sixth transport hand 126 move together in the horizontal direction. . The transport stage 125a and the transport stage 126a move along the fifth travel axis, and the transport stage 127a moves along the fourth travel axis at a position lower than the fifth travel axis. Accordingly, the transfer stages 125a, 126a, and 127a can move in the horizontal direction without contacting each other. The fourth travel shaft and the fifth travel shaft are located at the same height as the second travel shaft and the third travel shaft of the first linear transporter 6.

  The fifth transport hand 125 moves between the fifth transport position TP5 and the sixth transport position TP6. The fifth transfer hand 125 functions as an access hand that transfers wafers to and from the top ring 31C. The sixth transport hand 126 moves between the sixth transport position TP6 and the seventh transport position TP7. The sixth transfer hand 126 functions as an access hand for receiving a wafer from the top ring 31C and passing it to the top ring 31D. The seventh transport hand 127 moves between the seventh transport position TP7 and the fifth transport position TP5. The seventh transfer hand 127 functions as an access hand for receiving a wafer from the top ring 31D and transferring it to the fifth transfer position TP5. Although explanation is omitted, the operation at the time of wafer transfer between the transfer hands 125, 126, 127 and the top rings 31C, 31D is the same as the above-described operation of the first linear transporter 6.

  When the top rings shown in FIG. 4 are used as the top rings 31A to 31D, a retainer ring station described below is used in order to facilitate delivery of the wafer to the first and second linear transporters 6 and 7. It is preferable to provide the second transport position TP2, the third transport position TP3, the sixth transport position TP6, and the seventh transport position TP7, respectively.

  FIG. 18 is a perspective view for explaining the arrangement of the retainer ring station, the transport stage, and the top ring provided at the second transport position TP2, the third transport position TP3, the sixth transport position TP6, and the seventh transport position TP7. It is. FIG. 19 is a perspective view showing the retainer ring station and the transfer stage arranged at the second transfer position TP2. FIG. 20A is a side view showing the positional relationship between the retainer ring station and the top ring, and FIG. 20B is a plan view showing the positional relationship between the retainer ring station and the transfer stage. Hereinafter, the retainer ring station arranged at the second transfer position TP2 will be described.

  The retainer ring station 143 includes a plurality of push-up mechanisms 144 that push up the retainer ring 40 of the top ring 31A, and a support base 145 that supports these push-up mechanisms 144. The position of the push-up mechanism 144 in the height direction is between the top ring 31A and the transport stage (122a or 123a or 124a) of the first linear transporter 6. Further, as shown in FIG. 20B, the push-up mechanism 144 and the transfer stage are arranged so as not to contact each other.

  FIG. 21 is a perspective view showing a state in which the top ring is placed on the retainer ring station. 22A is a cross-sectional view showing the push-up mechanism 144, and FIG. 22B is a cross-sectional view showing the push-up mechanism 144 when it comes into contact with the retainer ring. The push-up mechanism 144 includes a push-up pin 146 that contacts the retainer ring 40, a spring 147 as a push mechanism that pushes the push-up pin 146 upward, and a casing 148 that houses the push-up pin 146 and the spring 147. The push-up mechanism 144 is disposed at a position where the push-up pin 146 faces the lower surface of the retainer ring 40. When the top ring 31 </ b> A descends, the lower surface of the retainer ring 40 comes into contact with the push-up pin 146. The spring 147 has a pressing force sufficient to push up the retainer ring 40. Therefore, as shown in FIG. 22B, the retainer ring 40 is pushed up by the push-up pins 146 and moves to a position above the wafer W.

  Next, an operation when a wafer is transferred from the first linear transporter 5 to the top ring 31A will be described. First, the top ring 31A moves from the polishing position to the first transport position TP1. Next, the top ring 31 </ b> A descends, and the retainer ring 40 is pushed up by the push-up mechanism 144 of the retainer ring station 143 as described above. When the top ring 31 </ b> A is lowered, the transport stage of the first linear transporter 5 is raised and moves to just below the top ring 31 </ b> A without contacting the retainer ring 40. In this state, the wafer W is transferred from the transfer stage to the top ring 31A. When the top ring 31A is raised, the transfer stage is lowered almost simultaneously. The top ring 31A further moves to the polishing position to polish the wafer W, and the transfer stage starts the next transfer operation. The same operation is performed when a wafer is transferred from the top ring 31A to the first linear transporter 5.

  As described above, when the wafer is transferred, the top ring 31A and the transfer stage are close to each other at approximately the same time and are separated from each other at approximately the same time, so that throughput can be improved. The configuration of the retainer ring station 143 provided at the third transfer position TP3, the sixth transfer position TP6, and the seventh transfer position TP7 is the same as the above-described retainer ring station 143, and the wafer transfer operation is performed in the same manner. .

  Since the retainer ring 40 is in sliding contact with the polishing surface of the polishing pad during polishing of the wafer, the lower surface of the retainer ring 40 is gradually worn. As the wear of the retainer ring 40 progresses, the retainer ring 40 cannot hold the wafer during polishing, and the wafer jumps out of the rotating top ring 31A. Therefore, it is necessary to replace the retainer ring 40 periodically. Conventionally, the replacement time of the retainer ring 40 has been determined based on the number of processed wafers. Therefore, even if the retainer ring 40 is still usable, the retainer ring 40 is replaced with a new retainer ring 40, or the wear is excessively advanced. Sometimes jumped out of the top ring 31A. In order to solve such a problem, in the following example, a wear measuring device for measuring the wear amount of the retainer ring 40 is provided in the retainer ring station 143.

  23 is a perspective view showing a retainer ring station 143 provided with a wear measuring device for measuring the wear amount of the retainer ring 40, and FIG. 24 is an enlarged sectional view showing the wear measuring device shown in FIG. 25 is a side view of the retainer ring station 143 and the top ring 31A. The wear measuring device 149 is installed on a support base 145 that supports the push-up mechanism 144, and the relative positions of the wear measuring device 149 and the push-up mechanism 144 are fixed. As shown in FIG. 24, the wear measuring instrument 149 supports a contact member 149a that contacts the lower surface of the retainer ring 40, a spring 149b that presses the contact member 149a upward, and a contact member 149a that is movable in the vertical direction. The linear motion guide 149c and the contact-type displacement sensor (displacement measuring device) 149d which measures the displacement of the contact member 149a are provided. A ball spline can be used as the linear motion guide 149c. Note that a non-contact displacement sensor such as an optical displacement sensor may be used instead of the contact displacement sensor.

  The contact member 149a has an inverted L shape when viewed from the side, and its lower end is located at substantially the same height as the push-up pin 146. When the top ring 31 </ b> A is placed on the retainer ring station 143, the lower end of the contact member 149 a comes into contact with the lower surface of the retainer ring 40 almost simultaneously with the push-up pin 146. The displacement sensor 149d is disposed above the contact member 149a. The upper end of the contact member 149a biased upward by the spring 149b is always in contact with the displacement sensor 149d. Therefore, the vertical displacement of the contact member 149a is measured by the displacement sensor 149d. The displacement sensor 149d is connected to the control unit 5, and the measurement value of the displacement sensor 149d is sent to the control unit 5.

  When the top ring 31A is lowered and placed on the retainer ring station 143, the push-up pin 146 and the contact member 149a contact the lower surface of the retainer ring 40 of the top ring 31A. The top ring 31A continues to descend until it stops at a predetermined height, and at the same time, the retainer ring 40 is pushed up by the push-up pin 146. At this time, the contact member 149a is pushed down by the retainer ring 40. The displacement of the contact member 149a is measured by the displacement sensor 149d, and the measured value is transmitted to the control unit 5. During the measurement by the displacement sensor 149d, the wafer is transferred between the top ring 31A and the transfer stage.

  The displacement of the contact member 149a, that is, the measured value of the displacement sensor 149d varies depending on the amount of wear of the retainer ring 40. More specifically, as the amount of wear of the retainer ring 40 increases, the measured value of the displacement sensor 149d decreases. A predetermined threshold value indicating the replacement time of the retainer ring 40 is set in the control unit 5. The controller 5 determines the replacement time of the retainer ring 40 by detecting that the measured value of the displacement sensor 149d has reached the threshold value. The retainer ring stations provided at the third transport position TP3, the sixth transport position TP6, and the seventh transport position TP7 are also preferably provided with the wear measuring device 149 as in the above-described retainer ring station 143.

  According to this example, since the replacement time of the retainer ring 40 is determined based on the amount of wear of the retainer ring 40, the replacement frequency of the retainer ring 40 can be reduced and the cost can be reduced. Further, it is possible to prevent the wafer from being popped out during polishing. Further, since the wear amount of the retainer ring 40 is measured during the transfer of the wafer between the top ring 31A and the transfer stage, the operation of measuring the wear amount of the retainer ring 40 decreases the throughput of the entire apparatus. There is nothing. That is, the push-up operation of the retainer ring 40 by the push-up pin 146 and the wear amount measurement operation of the retainer ring 40 by the wear measuring device 149 are necessarily performed simultaneously, so it is necessary to provide time for measuring the wear amount of the retainer ring 40. There is no. Therefore, the throughput of the entire apparatus is improved.

  FIG. 26 is a perspective view showing the structure of the lifter 11. The lifter 11 is disposed at a position accessible by the arm of the transfer robot 22 (see FIG. 1). The lifter 11 includes a mounting stage 150 on which a wafer is mounted, a support shaft 151 that supports the mounting stage 150, and a lift drive mechanism 152 that moves the mounting stage 150 up and down. As the elevation drive mechanism 152, a motor drive mechanism having a ball screw, an air cylinder, or the like is used. The placement stage 150 is located at the first transport position TP1. Four pins 153 are provided on the upper surface of the mounting stage 150, and the wafer W is mounted on these pins 153. The lower arm of the transfer robot 22 is configured to place the wafer on the placement stage 150 of the lifter 11 after rotating the wafer 180 degrees around its axis to invert the wafer. FIG. 26 shows the wafer W turned upside down. In this embodiment, since the arm of the transfer robot 22 also functions as a reversing machine, a reversing machine that has been conventionally required can be eliminated. Therefore, the step of inverting the wafer W after the lifter receives the wafer W can be omitted, and the throughput of the entire process can be improved.

  The transport stage 122a (or 121a or 123a) of the first linear transporter 6 at the first transport position TP1 and the mounting stage 150 of the lifter 11 are arranged along the same vertical axis. As shown in FIG. 26, when viewed from the vertical direction, the transfer stage 122a and the mounting stage 150 have shapes that do not overlap each other. More specifically, a notch 155 through which the mounting stage 150 of the lifter 11 passes is formed in the transport stage 122a of the first linear transporter 6. This notch 155 is formed to be slightly larger than the mounting stage 150.

  The lifter 11 receives the wafer W inverted by the arm of the transfer robot 22 at a position where the mounting stage 150 is lifted, and then the mounting stage 150 is driven by the lift drive mechanism 152 and is lowered. When the mounting stage 150 passes through the transfer stage 122a of the first linear transporter 6, only the wafer W is mounted on the transfer stage 122a, and the mounting stage 150 continues to descend to a predetermined stop position. As a result, the wafer W is transferred from the lifter 11 to the first linear transporter 6. In this embodiment, since the arm of the transfer robot 22 also functions as a reversing machine, a reversing machine that has been conventionally required can be eliminated. Accordingly, it is possible to reduce the number of wafers transferred when the transfer robot 22 transfers the first linear transporter 6, and to reduce wafer transfer mistakes and transfer time.

  The support shaft 151 of the lifter 11 has an inverted L-shaped shape, and the vertical portion thereof is located outside the mounting stage 150. That is, when the lifter 11 is viewed from the vertical direction, the mounting stage 150 and the vertical portion of the support shaft 151 are in positions that do not overlap each other. Further, the support shaft 151 is located at a position away from the travel path of the transport stage of the first linear transporter 6. Therefore, regardless of the vertical position of the mounting stage 150 of the lifter 11, the transfer stage of the first linear transporter 6 can enter the first transfer position TP1, and the throughput can be increased.

  FIG. 27 is a perspective view showing the structure of the swing transporter 12. The swing transporter 12 is installed on the frame 160 of the substrate processing apparatus, and includes a linear guide 161 extending in the vertical direction, a swing mechanism 162 attached to the linear guide 161, and a drive source for moving the swing mechanism 162 in the vertical direction. As a lifting drive mechanism 165. As the elevating drive mechanism 165, a robot cylinder having a servo motor and a ball screw can be adopted. A reversing mechanism 167 is connected to the swing mechanism 162 via a swing arm 166. Further, a gripping mechanism 170 that grips the wafer W is connected to the reversing mechanism 167. On the side of the swing transporter 12, a temporary placement table 180 for a wafer W installed in a frame (not shown) is disposed. As shown in FIG. 1, the temporary placement table 180 is disposed adjacent to the first linear transporter 6 and is positioned between the first linear transporter 6 and the cleaning unit 4.

  The swing arm 166 is rotated about the rotation axis of the motor by driving a motor (not shown) of the swing mechanism 162. As a result, the reversing mechanism 167 and the gripping mechanism 170 integrally rotate, and the gripping mechanism 170 moves between the fourth transport position TP4, the fifth transport position TP5, and the temporary placement table 180.

  The gripping mechanism 170 has a pair of gripping arms 171 that grip the wafer W. At both ends of each gripping arm 171, chucks 172 that grip the outer peripheral edge of the wafer W are provided. These chucks 172 are provided so as to protrude downward from both ends of the grip arm 171. Further, the gripping mechanism 170 includes an opening / closing mechanism 173 that moves the pair of gripping arms 171 in the direction of approaching and separating from the wafer W.

  When gripping the wafer W, the gripping mechanism 170 is lowered by the lift drive mechanism 165 until the chuck 172 of the gripping arm 171 is positioned in the same plane as the wafer W with the gripping arm 171 open. Then, the opening / closing mechanism 173 is driven to move the gripping arms 171 in a direction approaching each other, and the outer peripheral edge of the wafer W is gripped by the chuck 172 of the gripping arm 171. In this state, the lifting / lowering drive mechanism 165 raises the grip arm 171.

  The reversing mechanism 167 has a rotating shaft 168 coupled to the gripping mechanism 170 and a motor (not shown) that rotates the rotating shaft 168. By driving the rotation shaft 168 by the motor, the entire gripping mechanism 170 is rotated by 180 degrees, whereby the wafer W gripped by the gripping mechanism 170 is reversed. As described above, since the entire gripping mechanism 170 is reversed by the reversing mechanism 167, it is possible to omit the transfer of the wafer between the gripping mechanism and the reversing mechanism, which is conventionally required. When the wafer W is transferred from the fourth transfer position TP4 to the fifth transfer position TP5, the reversing mechanism 167 does not reverse the wafer W, and the wafer W is transferred with the surface to be polished facing downward. On the other hand, when the wafer W is transferred from the fourth transfer position TP4 or the fifth transfer position TP5 to the temporary placement table 180, the wafer W is reversed by the reversing mechanism 167 so that the polished surface faces upward.

  The temporary table 180 includes a base plate 181, a plurality of (two in FIG. 27) vertical rods 182 fixed to the upper surface of the base plate 181, and one inverted L-shaped horizontal that is fixed to the upper surface of the base plate 181. Rod 183. The horizontal rod 183 includes a vertical portion 183a connected to the upper surface of the base plate 181 and a horizontal portion 183b extending horizontally from the upper end of the vertical portion 183a toward the gripping mechanism 170. A plurality of (two in FIG. 27) pins 184 for supporting the wafer W are provided on the upper surface of the horizontal portion 183b. Pins 184 for supporting the wafer W are also provided at the upper ends of the vertical rods 182. The tips of these pins 184 are located in the same horizontal plane. The horizontal rod 183 is disposed closer to the center of the turning movement of the wafer W than the vertical rod 182 (that is, the rotation axis of the motor of the swing mechanism 162).

  The gripping mechanism 170 reversed by the reversing mechanism 167 enters the gap between the horizontal portion 183b of the horizontal rod 183 and the base plate 181 while gripping the wafer W, and all the pins 184 are positioned below the wafer W. Then, the swing of the gripping mechanism 170 by the swing mechanism 162 is stopped. The wafer W is placed on the temporary placement table 180 by opening the gripping arm 171 in this state. The wafer W placed on the temporary placement table 180 is transferred to the cleaning unit 4 by the transfer robot of the cleaning unit 4 described below.

  FIG. 28A is a plan view showing the cleaning unit 4, and FIG. 28B is a side view showing the cleaning unit 4. As shown in FIGS. 28A and 28B, the cleaning unit 4 includes a first cleaning chamber 190, a first transfer chamber 191, a second cleaning chamber 192, a second transfer chamber 193, and a drying unit. It is partitioned into a chamber 194. In the first cleaning chamber 190, an upper primary cleaning module 201A and a lower primary cleaning module 201B arranged in the vertical direction are arranged. The upper primary cleaning module 201A is disposed above the lower primary cleaning module 201B. Similarly, in the second cleaning chamber 192, an upper secondary cleaning module 202A and a lower secondary cleaning module 202B arranged in the vertical direction are arranged. The upper secondary cleaning module 202A is disposed above the lower secondary cleaning module 202B. The primary and secondary cleaning modules 201A, 201B, 202A, and 202B are cleaning machines that clean a wafer using a cleaning liquid. Since these primary and secondary cleaning modules 201A, 201B, 202A, 202B are arranged along the vertical direction, there is an advantage that the footprint area is small.

  A temporary wafer placement table 203 is provided between the upper secondary cleaning module 202A and the lower secondary cleaning module 202B. In the drying chamber 194, an upper drying module 205A and a lower drying module 205B arranged in the vertical direction are arranged. The upper drying module 205A and the lower drying module 205B are isolated from each other. Filter fan units 207 and 207 for supplying clean air into the drying modules 205A and 205B are provided above the upper drying module 205A and the lower drying module 205B, respectively. The upper primary cleaning module 201A, the lower primary cleaning module 201B, the upper secondary cleaning module 202A, the lower secondary cleaning module 202B, the temporary placing table 203, the upper drying module 205A, and the lower drying module 205B are arranged on a frame (not shown). It is fixed via bolts.

  A first transfer robot 209 that can move up and down is arranged in the first transfer chamber 191, and a second transfer robot 210 that can move up and down is arranged in the second transfer chamber 193. The first transfer robot 209 and the second transfer robot 210 are movably supported by support shafts 211 and 212 extending in the vertical direction. The first transfer robot 209 and the second transfer robot 210 have a drive mechanism such as a motor inside thereof, and are movable up and down along the support shafts 211 and 212. The first transfer robot 209 has two upper and lower hands like the transfer robot 22. As shown by the dotted line in FIG. 28A, the first transfer robot 209 is disposed at a position where the lower hand can access the temporary table 180 described above. When the lower hand of the first transfer robot 209 accesses the temporary table 180, a shutter (not shown) provided on the partition wall 1b is opened.

  The first transfer robot 209 transfers the wafer W between the temporary placing table 180, the upper primary cleaning module 201A, the lower primary cleaning module 201B, the temporary placing table 203, the upper secondary cleaning module 202A, and the lower secondary cleaning module 202B. Operates to carry. The first transfer robot 209 uses the lower hand when transferring the wafer before cleaning (the wafer to which the slurry is attached), and uses the upper hand when transferring the cleaned wafer. The second transfer robot 210 operates to transfer the wafer W between the upper secondary cleaning module 202A, the lower secondary cleaning module 202B, the temporary placement table 203, the upper drying module 205A, and the lower drying module 205B. Since the second transfer robot 210 transfers only the cleaned wafer, it has only one hand. The transfer robot 22 shown in FIG. 1 takes out the wafer from the upper drying module 205A or the lower drying module 205B using the upper hand, and returns the wafer to the wafer cassette. When the upper hand of the transfer robot 22 accesses the drying modules 205A and 205B, a shutter (not shown) provided on the partition wall 1a is opened.

  Since the cleaning unit 4 includes two primary cleaning modules and two secondary cleaning modules, a plurality of cleaning lines for cleaning a plurality of wafers in parallel can be configured. The “cleaning line” is a moving path when one wafer is cleaned by a plurality of cleaning modules inside the cleaning unit 4. For example, as shown in FIG. 29, one wafer is divided into a first transfer robot 209, an upper primary cleaning module 201A, a first transfer robot 209, an upper secondary cleaning module 202A, a second transfer robot 210, and an upper drying module 205A. (See cleaning line 1), and in parallel with this, other wafers are transferred to the first transfer robot 209, the lower primary cleaning module 201B, the first transfer robot 209, the lower secondary cleaning module 202B, The second transfer robot 210 and the lower drying module 205B can be transferred in this order (see the cleaning line 2). In this manner, a plurality of (typically two) wafers can be cleaned and dried almost simultaneously by two parallel cleaning lines.

  Further, in two parallel cleaning lines, a plurality of wafers can be cleaned and dried with a predetermined time difference. The advantages of cleaning at a predetermined time difference are as follows. The first transfer robot 209 and the second transfer robot 210 are shared by a plurality of cleaning lines. For this reason, when a plurality of cleaning or drying processes are completed at the same time, these transfer robots cannot immediately transfer the wafer, thereby deteriorating the throughput. In order to avoid such a problem, the processed wafers can be quickly transferred by the transfer robots 209 and 210 by cleaning and drying a plurality of wafers with a predetermined time difference.

  The slurry is adhered to the polished wafer, and it is not preferable to leave the wafer for a long time in that state. This is because copper as a wiring metal may be corroded by the slurry. According to the cleaning unit 4, since two primary cleaning modules are provided, even when the preceding wafer is cleaned by either the upper primary cleaning module 201A or the lower primary cleaning module 201B, The wafer can be carried into the primary cleaning module and cleaned. Accordingly, not only high throughput can be realized, but also the polished wafer can be cleaned immediately to prevent copper corrosion.

  When only the primary cleaning is required, as shown in FIG. 30, the wafer is transferred to the first transfer robot 209, the upper primary cleaning module 201A, the first transfer robot 209, the temporary placing table 203, the second transfer robot 210, And it can convey in order of the upper side drying module 205A, and the secondary washing | cleaning in the 2nd washing | cleaning chamber 192 can be abbreviate | omitted. Further, as shown in FIG. 31, for example, when the lower secondary cleaning module 202B is in failure, the wafer can be transferred to the upper secondary cleaning module 202A. As described above, the first transfer robot 209 and the second transfer robot 210 can distribute the wafer to a predetermined cleaning line as necessary. The selection of such a cleaning line is determined by the control unit 5.

  Each cleaning module 201A, 201B, 202A, 202B has a detector (not shown) that detects a failure. When any of the cleaning modules 201A, 201B, 202A, 202B fails, the detector detects this and sends a signal to the control unit 5. The control unit 5 selects a cleaning line that avoids the faulty cleaning module, and switches the current cleaning line to the newly selected cleaning line. In this embodiment, two primary cleaning modules and two secondary cleaning modules are provided. However, the present invention is not limited to this, and three or more primary cleaning modules and / or secondary cleaning modules are provided. It is good.

  In addition, a temporary placement table may be provided in the first cleaning chamber 190. For example, similarly to the temporary table 203, a temporary table can be installed between the upper primary cleaning module 201A and the lower primary cleaning module 201B. When a certain cleaning module fails, two wafers can be transferred to the temporary table 180 (see FIG. 28A) and the temporary table in the first cleaning chamber 190.

  The concentration of the cleaning liquid used in the primary cleaning modules 201A and 201B may be different from the concentration of the cleaning liquid used in the secondary cleaning modules 202A and 202B. For example, the concentration of the cleaning liquid used in the primary cleaning modules 201A and 201B is set higher than the concentration of the cleaning liquid used in the secondary cleaning modules 202A and 202B. Usually, the cleaning effect is considered to be approximately proportional to the concentration of the cleaning liquid and the cleaning time. Therefore, by using a cleaning solution having a high concentration in the primary cleaning, the time for the primary cleaning and the time for the secondary cleaning can be made substantially equal even when the wafer is very dirty.

In the present embodiment, the primary cleaning modules 201A and 201B and the secondary cleaning modules 202A and 202B are roll sponge type cleaning machines. Since the primary cleaning modules 201A and 201B and the secondary cleaning modules 202A and 202B have the same configuration, the primary cleaning module 201A will be described below.
FIG. 32 is a perspective view showing the primary cleaning module 201A. As shown in FIG. 32, the primary cleaning module 201A includes four rollers 301, 302, 303, 304 that hold and rotate the wafer W, and roll sponges (cleaning tools) 307, 308 that contact the upper and lower surfaces of the wafer W. Rotating mechanisms 310 and 311 for rotating the roll sponges 307 and 308, cleaning liquid supply nozzles 315 and 316 for supplying a cleaning liquid (for example, pure water) to the upper and lower surfaces of the wafer W, and etching liquid ( Etching solution supply nozzles 317 and 318 for supplying a chemical solution). The rollers 301, 302, 303, and 304 can be moved toward and away from each other by a driving mechanism (not shown) (for example, an air cylinder).

  A rotating mechanism 310 that rotates the upper roll sponge 307 is attached to a guide rail 320 that guides its vertical movement. The rotating mechanism 310 is supported by an elevating drive mechanism 321, and the rotating mechanism 310 and the upper roll sponge 307 are moved up and down by the elevating drive mechanism 321. Although not shown, a rotating mechanism 311 for rotating the lower roll sponge 308 is also supported by the guide rail, and the rotating mechanism 311 and the lower roll sponge 308 are moved up and down by an elevating drive mechanism. . For example, a motor drive mechanism using a ball screw or an air cylinder is used as the lifting drive mechanism.

  When the wafer W is loaded and unloaded, the roll sponges 307 and 308 are at positions separated from each other. At the time of cleaning the wafer W, the roll sponges 307 and 308 move in directions close to each other and come into contact with the upper and lower surfaces of the wafer W. The forces with which the roll sponges 307 and 308 press the upper and lower surfaces of the wafer W are adjusted by an elevation drive mechanism 321 and an elevation drive mechanism (not shown), respectively. Since the upper roll sponge 307 and the rotation mechanism 310 are supported from below by the elevation drive mechanism 321, the pressing force applied to the upper surface of the wafer W by the upper roll sponge 307 can be adjusted from 0 [N].

  The roller 301 has a two-stage configuration of a holding part 301a and a shoulder part (supporting part) 301b. The diameter of the shoulder portion 301b is larger than the diameter of the holding portion 301a, and the holding portion 301a is formed on the shoulder portion 301b. The rollers 302, 303, and 304 have the same configuration as the roller 301. The wafer W transferred by the lower arm of the first transfer robot 209 is first placed on the shoulders 301b, 302b, 303b, and 304b, and then the rollers 301, 302, 303, and 304 are directed toward the wafer W. By moving, it is held by the holding portions 301a, 302a, 303a, 304a. At least one of the four rollers 301, 302, 303, and 304 is configured to be rotationally driven by a rotation mechanism (not shown), whereby the outer periphery of the wafer W is held by the rollers 301, 302, 303, and 304. It rotates in the state that was done. The shoulder portions 301b, 302b, 303b, and 304b are tapered surfaces that are inclined downward, and the wafer W is held by the shoulder portions 301b, 302b, 303b, and 304b while being held by the holding portions 301a, 302a, 303a, and 304a. It is kept non-contact.

  The cleaning operation is performed as follows. First, the wafer W is held by rollers 301, 302, 303, and 304 and rotated. Next, cleaning water is supplied from the cleaning liquid supply nozzles 315 and 316 to the upper and lower surfaces of the wafer W. Then, the upper and lower surfaces of the wafer W are scrubbed by the roll sponges 307 and 308 being slidably contacted with the upper and lower surfaces of the wafer W while rotating around its axis. After scrub cleaning, roll sponges 307 and 308 are retracted upward and downward, and an etching solution is supplied from the chemical solution supply nozzles 317 and 318 to the upper and lower surfaces of the wafer W, respectively, so that the upper and lower surfaces of the wafer W are etched (chemical cleaning). I do.

The upper primary cleaning module 201A, the lower primary cleaning module 201B, the upper secondary cleaning module 202A, and the lower secondary cleaning module 202B may be the same type of cleaning module or different types of cleaning modules. For example, the primary cleaning modules 201A and 201B are scrub cleaning types that clean the upper and lower surfaces of the wafer with a pair of roll sponges, and the secondary cleaning modules 202A and 202B are pencil sponge type cleaning devices or two-fluid jet type cleaning devices. You can also The two-fluid jet type cleaning machine is a cleaning machine that mixes pure water (DIW) in which a small amount of CO ₂ gas (carbon dioxide gas) is dissolved and N ₂ gas, and sprays the mixed fluid onto the surface of the wafer. This type of cleaning machine can remove minute particles on the wafer with minute droplets and impact energy. In particular, the wafer cleaning without damage can be realized by appropriately adjusting the flow rate of N ₂ gas and the flow rate of pure water. Further, by using pure water in which carbon dioxide gas is dissolved, the influence of wafer corrosion caused by static electricity is mitigated.

  Next, the configuration of the upper drying module 205A and the lower drying module 205B will be described. The upper drying module 205A and the lower drying module 205B are both dryers that perform rotagony drying. Since the upper drying module 205A and the lower drying module 205B have the same configuration, the upper drying module 205A will be described below. FIG. 33 is a longitudinal sectional view showing the upper drying module 205A, and FIG. 34 is a plan view showing the upper drying module 205A. The upper drying module 205 </ b> A includes a base 401 and four cylindrical substrate support members 402 supported by the base 401. The base 401 is fixed to the upper end of the rotating shaft 406, and the rotating shaft 406 is rotatably supported by a bearing 405. The bearing 405 is fixed to the inner peripheral surface of a cylindrical body 407 extending in parallel with the rotation shaft 406. The lower end of the cylindrical body 407 is attached to the mount 409, and its position is fixed. The rotating shaft 406 is connected to a motor 415 via pulleys 411 and 412 and a belt 414. By driving the motor 415, the base 401 rotates about its axis.

  A rotation cover 450 is fixed on the upper surface of the base 401. FIG. 33 shows a longitudinal section of the rotary cover 450. The rotation cover 450 is disposed so as to surround the entire circumference of the wafer W. The vertical cross-sectional shape of the rotating cover 450 is inclined radially inward. In addition, the vertical cross section of the rotating cover 450 is composed of a smooth curve. The upper end of the rotating cover 450 is close to the wafer W, and the inner diameter of the upper end of the rotating cover 450 is set slightly larger than the diameter of the wafer W. Further, a notch 450 a along the outer peripheral surface shape of the substrate support member 402 is formed at the upper end of the rotation cover 450 corresponding to each substrate support member 402. A liquid discharge hole 451 extending obliquely is formed on the bottom surface of the rotary cover 450.

Above the wafer W, a front nozzle 454 for supplying pure water as a cleaning liquid to the surface (front surface) of the wafer W is disposed. The front nozzle 454 is arranged facing the center of the wafer W. The front nozzle 454 is connected to a pure water supply source (cleaning liquid supply source) (not shown) so that pure water is supplied to the center of the surface of the wafer W through the front nozzle 454. Examples of the cleaning liquid include chemical liquids in addition to pure water. Further, above the wafer W, two nozzles 460 and 461 for performing rotagony drying are arranged in parallel. The nozzle 460 is for supplying IPA vapor (mixture of isopropyl alcohol and N ₂ gas) to the surface of the wafer W, and the nozzle 461 is for supplying pure water to prevent the surface of the wafer W from being dried. It is. These nozzles 460 and 461 are configured to be movable along the radial direction of the wafer W.

Inside the rotating shaft 406, a back nozzle 463 connected to a cleaning liquid supply source 465 and a gas nozzle 464 connected to a dry gas supply source 466 are arranged. The cleaning liquid supply source 465 stores pure water as the cleaning liquid, and the pure water is supplied to the back surface of the wafer W through the back nozzle 463. The dry gas supply source 466 stores N ₂ gas or dry air as a dry gas, and the dry gas is supplied to the back surface of the wafer W through the gas nozzle 464.

  A lift mechanism 470 for lifting the substrate support member 402 is disposed around the cylindrical body 407. The lift mechanism 470 is configured to be slidable in the vertical direction with respect to the cylindrical body 407. The lift mechanism 470 has a contact plate 470 a that contacts the lower end of the substrate support member 402. A first gas chamber 471 and a second gas chamber 472 are formed between the outer peripheral surface of the cylindrical body 407 and the inner peripheral surface of the lift mechanism 470. The first gas chamber 471 and the second gas chamber 472 communicate with the first gas channel 474 and the second gas channel 475, respectively. The end of the gas channel 475 is connected to a pressurized gas supply source (not shown). When the pressure in the first gas chamber 471 is made higher than the pressure in the second gas chamber 472, the lift mechanism 470 is raised. On the other hand, when the pressure in the second gas chamber 472 is higher than the pressure in the first gas chamber 471, the lift mechanism 470 is lowered. FIG. 33 shows a state where the lift mechanism 470 is in the lowered position.

  FIG. 35 is a plan view of the base 401 shown in FIG. As shown in FIG. 35, the base 401 has four arms 401a, and a substrate support member 402 is supported at the tip of each arm 401a so as to be movable up and down. 36A is a plan view showing a part of the substrate support member 402 and the base 401 shown in FIG. 35, and FIG. 36B is a cross-sectional view taken along the line AA in FIG. FIG. 36C is a sectional view taken along line BB in FIG. The arm 401a of the base 401 has a holding portion 401b that holds the substrate support member 402 in a slidable manner. In addition, you may comprise this holding | maintenance part 401b integrally with the arm 401a. A through hole extending vertically is formed in the holding portion 401b, and the substrate support member 402 is inserted into the through hole. The diameter of the through hole is slightly larger than the diameter of the substrate support member 402. Therefore, the substrate support member 402 can move relative to the base 401 in the vertical direction, and the substrate support member 402 has its axis. It can be rotated around.

  A spring receiver 402 a is attached to the lower part of the substrate support member 402. A spring 478 is disposed around the substrate support member 402, and the spring 478 is supported by a spring receiver 402a. The upper end of the spring 478 presses the holding portion 401b (a part of the base 401). Accordingly, a downward force is applied to the substrate support member 402 by the spring 478. A stopper 402 b having a diameter larger than the diameter of the through hole is formed on the outer peripheral surface of the substrate support member 402. Therefore, as shown in FIG. 36B, the substrate support member 402 is restricted from moving downward by the stopper 402b.

  At the upper end of the substrate support member 402, support pins 479 on which the wafer W is placed, and a cylindrical clamp 480 as a substrate gripping portion that abuts on the peripheral end of the wafer W are provided. The support pins 479 are disposed on the axis of the substrate support member 402, and the clamp 480 is disposed at a position separated from the axis of the substrate support member 402. Therefore, the clamp 480 can rotate around the axis of the substrate support member 402 as the substrate support member 402 rotates. Here, it is preferable to use a conductive member (preferably, iron, aluminum, SUS) or a carbon resin such as PEEK or PVC as a member of a portion in contact with the wafer W in order to prevent charging.

  A first magnet 481 is attached to the holding portion 401 b of the base 401, and the first magnet 481 is disposed to face the side surface of the substrate support member 402. On the other hand, the substrate support member 402 is provided with a second magnet 482 and a third magnet 483. The second magnet 482 and the third magnet 483 are arranged apart from each other in the vertical direction. As these first to third magnets 481, 482, 483, neodymium magnets are preferably used.

  FIG. 37 is a schematic diagram for explaining the arrangement of the second magnet 482 and the third magnet 483, and is a view seen from the axial direction of the substrate support member 402. As shown in FIG. 37, the second magnet 482 and the third magnet 483 are displaced from each other in the circumferential direction of the substrate support member 402. That is, the line connecting the second magnet 482 and the center of the substrate support member 402 and the line connecting the second magnet 482 and the center of the substrate support member 402 are viewed from the axial direction of the substrate support member 402. Sometimes they intersect at a predetermined angle α.

  When the substrate support member 402 is in the lowered position shown in FIG. 36B, the first magnet 481 and the second magnet 482 face each other. At this time, an attractive force acts between the first magnet 481 and the second magnet 482. This suction force gives the substrate support member 402 a force that rotates around its axis, and the rotation direction is a direction in which the clamp 480 presses the peripheral edge of the wafer W. Therefore, it can be said that the lowered position shown in FIG. 36B is a clamp position for gripping the wafer W.

  Note that the first magnet 481 and the second magnet 482 may not necessarily face each other when the wafer W is gripped as long as they are close enough to generate a sufficient gripping force. For example, even when the first magnet 481 and the second magnet 482 are close to each other in an inclined state, a magnetic force is generated between them. Therefore, as long as this magnetic force is large enough to rotate the substrate support member 402 and grip the wafer W, the first magnet 481 and the second magnet 482 do not necessarily face each other.

38A is a plan view showing a part of the substrate support member 402 and the arm 401a when the substrate support member 402 is lifted by the lift mechanism 470. FIG. 38B is a plan view showing the substrate by the lift mechanism 470. FIG. It is the sectional view on the AA line of FIG. 35 when the support member 402 is raised, and FIG.38 (c) is the sectional view on the CC line of FIG.38 (b).
When the substrate holding member 402 is raised to the raised position shown in FIG. 38B by the lift mechanism 470, the first magnet 481 and the third magnet 483 face each other, and the second magnet 482 becomes the first magnet 481. Separate from. At this time, an attractive force acts between the first magnet 481 and the third magnet 483. This suction force gives the substrate support member 402 a force that rotates around its axis, and the rotation direction is the direction in which the clamp 480 is separated from the wafer W. Therefore, it can be said that the raised position shown in FIG. 38A is an unclamping position for releasing the substrate. Also in this case, the first magnet 481 and the third magnet 483 do not necessarily face each other when the gripping of the wafer W is released, and the substrate support member 402 in a direction in which the clamp 480 is separated from the wafer W. As long as they are close enough to generate a rotational force (magnetic force) of rotating the.

  Since the second magnet 482 and the third magnet 483 are arranged at positions shifted in the circumferential direction of the substrate support member 402, the substrate support member 402 receives a rotational force as the substrate support member 402 moves up and down. Works. This rotational force gives the clamp 480 a force for gripping the wafer W and a force for opening the wafer W. Therefore, the wafer W can be gripped and released simply by moving the substrate support member 402 up and down. As described above, the first magnet 481, the second magnet 482, and the third magnet 483 rotate the substrate support member 402 around its axis and grips the wafer W by the clamp 480. ). This gripping mechanism (rotating mechanism) is operated by the vertical movement of the substrate support member 402.

  The contact plate 470 a of the lift mechanism 470 is located below the substrate support member 402. When the contact plate 470a rises, the upper surface of the contact plate 470a comes into contact with the lower end of the substrate support member 402, and the substrate support member 402 is lifted by the contact plate 470a against the pressing force of the spring 478. The upper surface of the contact plate 470a is a flat surface, while the lower end of the substrate support member 402 is formed in a hemispherical shape. In the present embodiment, the lift mechanism 470 and the spring 478 constitute a drive mechanism that moves the substrate support member 402 up and down. Note that the drive mechanism is not limited to the above-described embodiment, and for example, a configuration using a servo motor may be employed.

  A groove 484 extending along the axis is formed on the side surface of the substrate support member 402. The groove 484 has an arcuate horizontal cross section. A protruding portion 485 that protrudes toward the groove 484 is formed on the arm 401 a (the holding portion 401 b in this embodiment) of the base 401. The tip of the protrusion 485 is located inside the groove 484, and the protrusion 485 is gently engaged with the groove 484. The grooves 484 and the protrusions 485 are provided to limit the rotation angle of the substrate support member 402.

FIG. 39 is a schematic diagram showing an IPA supply unit that supplies IPA vapor (a mixture of isopropyl alcohol and N ₂ gas) to the nozzle 460. This IPA supply unit is installed in the substrate processing apparatus. As shown in FIG. 39, the IPA supply unit includes a bubbling tank 501 made of a metal such as stainless steel. A bubbler 502 that generates a bubble of N ₂ gas is disposed at the bottom inside the bubbling tank 501. Bubbler 502 is connected to the _{N 2} gas bubbling line 503, is further the _{N 2} gas bubbling line 503 is connected to a _{N 2} gas inlet line 504. The N ₂ gas introduction line 504 is connected to the N ₂ gas supply source 505. The N ₂ gas introduction line 504 and the N ₂ gas bubbling line 503 are provided with regulating valves 514 and 515, respectively.

The N ₂ gas bubbling line 503 is provided with a mass flow controller 520 and a filter 521. N ₂ gas is supplied from the N ₂ gas supply source 505 to the bubbler 502 through the N ₂ gas introduction line 504, the N ₂ gas bubbling line 503, and the filter 521. The N ₂ gas is maintained at a constant flow rate by the mass flow controller 520. A preferable supply flow rate of the N ₂ gas to the bubbler 502 is about 0 to 10 SLM. The unit SLM is an abbreviation for Standard Litter per Minute, and is a unit that represents the flow rate of gas at 0 ° C. and 1 atm.

  An IPA liquid supply line 506 and an IPA vapor transfer line 507 are further connected to the bubbling tank 501. The IPA vapor transfer line 507 is connected via a filter 522 to the nozzles 460 (see FIG. 33) of the upper drying module 205A and the lower drying module 205B. The IPA liquid supply line 506 is connected to an IPA supply source 508, and liquid IPA (isopropyl alcohol) is supplied to the bubbling tank 501 through the IPA liquid supply line 506. In the bubbling tank 501, a liquid level sensor (not shown) for detecting the liquid level of the IPA liquid in the bubbling tank 501 is installed. An adjustment valve 516 is provided in the IPA liquid supply line 506, and the IPA liquid is supplied by the adjustment valve 516 so that the output signal of the liquid level sensor (that is, the liquid level position of the IPA liquid) is within a predetermined range. The flow rate is adjusted. For example, 200 mL to 700 mL of IPA liquid is stored in the bubbling tank 501.

  Normally, when bubbling is continuously performed, the temperature of the IPA liquid in the bubbling tank 501 decreases due to the evaporation heat (vaporization heat) of IPA. When the temperature of the IPA liquid is lowered, the concentration of the IPA vapor is lowered, and stable drying of the wafer becomes difficult. Therefore, a water jacket 510 is provided around the bubbling tank 501 in order to keep the temperature of the IPA liquid constant. Warm water is circulated in the water jacket 510, whereby the temperature of the IPA liquid stored in the bubbling tank 501 is kept constant. The warm water flows into the water jacket 510 from the inlet provided at the lower part of the water jacket 510 and flows out from the outlet provided at the upper part of the water jacket 510. A preferable flow rate of the warm water flowing through the water jacket 510 is 50 mL / min to 200 mL / min, and a preferable temperature of the warm water is 22 to 25 ° C. In this embodiment, DIW (ultra pure water) is used as the heat retaining water, but other media may be used.

IPA vapor is generated by bubbling N ₂ gas in the IPA liquid, and IPA vapor is accumulated in the upper space in the bubbling tank 501. The IPA vapor is sent to the nozzles 460 (see FIG. 33) of the upper drying module 205A and the lower drying module 205B through the IPA vapor transfer line 507 and the filter 522. By passing through the filter 522, the IPA vapor supplied to the wafer is kept clean. The preferred temperature of the IPA vapor is 18-25 ° C. This is because no thermal stress is applied to the wafer.

  A preferable concentration of the IPA vapor generated in the bubbling tank 501 is about 0 to 4 vol%. When the temperature of the heat retaining water itself is increased, the temperature of the IPA liquid in the bubbling tank 501 increases, and the concentration of vaporized IPA increases. Therefore, the concentration of the IPA vapor can be adjusted by the temperature of the warm water. As an advantage of heating the IPA liquid using the heat retaining water, it is not necessary to provide an electric heat generation source such as a heater, and the safety of the substrate processing apparatus can be ensured.

As a bypass line for connecting the N ₂ gas introducing line 504 and the IPA vapor transport line 507, _{N 2} dilution line 525 is provided. The N ₂ dilution line 525 is provided with a mass flow controller 527, a regulating valve 528, and a check valve 529. By transferring directly to IPA vapor transport line 507 with N ₂ gas through the _{N 2} dilution line 525, it is possible to dilute the IPA vapor by _{N 2} gas. The flow rate of N ₂ gas transferred to the IPA vapor transfer line 507 is controlled by the mass flow controller 527.

An IPA relief line 530 is connected to the upper portion of the bubbling tank 501. The IPA relief line 530 is provided with a regulating valve 532, a check valve 533, and a release valve 534. The regulating valve 532 and the release valve 534 are arranged in parallel. When the pressure in the bubbling tank 501 exceeds a certain value, the release valve 534 is opened, and the IPA vapor in the bubbling tank 501 is released to the outside. Further, when IPA is replenished to the bubbling tank 501, the adjustment valve 532 is opened, and the pressure in the bubbling tank 501 becomes atmospheric pressure. Note that the regulating valves 515 and 528 may be closed valves. In this case, the flow rate of N ₂ gas is adjusted by the mass flow controllers 520 and 527, while the flow of N ₂ gas is blocked by the closing valves 515 and 528.

Next, the operation of the drying module 205A configured as described above will be described.
First, the motor 415 rotates the wafer W and the rotating cover 450 together. In this state, pure water is supplied from the front nozzle 454 and the back nozzle 463 to the front surface (upper surface) and back surface (lower surface) of the wafer W, and the entire surface of the wafer W is rinsed with pure water. The pure water supplied to the wafer W spreads over the entire front and back surfaces of the wafer W due to centrifugal force, whereby the entire wafer W is rinsed. The pure water shaken off from the rotating wafer W is captured by the rotating cover 450 and flows into the liquid discharge hole 451. During the rinsing process of the wafer W, the two nozzles 460 and 461 are at predetermined standby positions apart from the wafer W.

Next, the supply of pure water from the front nozzle 454 is stopped, the front nozzle 454 is moved to a predetermined standby position away from the wafer W, and the two nozzles 460 and 461 are moved to a working position above the wafer W. Let Then, IPA vapor is supplied from the nozzle 460 and pure water is supplied from the nozzle 461 toward the surface of the wafer W while rotating the wafer W at a low speed of 30 to 150 min ⁻¹ . At this time, pure water is also supplied from the back nozzle 463 to the back surface of the wafer W. Then, the two nozzles 460 and 461 are simultaneously moved along the radial direction of the wafer W. Thereby, the surface (upper surface) of the wafer W is dried.

Thereafter, the two nozzles 460 and 461 are moved to a predetermined standby position, and the supply of pure water from the back nozzle 463 is stopped. Then, the wafer W is rotated at a high speed of 1000 to 1500 min ^{−1 and} the pure water adhering to the back surface of the wafer W is shaken off. At this time, dry gas is blown from the gas nozzle 464 to the back surface of the wafer W. In this way, the back surface of the wafer W is dried. The dried wafer W is taken out from the drying module 205A by the transfer robot 22 shown in FIG. 1 and returned to the wafer cassette. In this way, a series of processes including polishing, cleaning, and drying are performed on the wafer. According to the drying module 205A configured as described above, both surfaces of the wafer W can be quickly and effectively dried, and the end point of the drying process can be accurately controlled. Therefore, the processing time for the drying process does not become a rate-limiting step of the entire cleaning process. Moreover, since the processing time in the above-described plurality of cleaning lines formed in the cleaning unit 4 can be leveled, the throughput of the entire process can be improved.

  The embodiment described above is described for the purpose of enabling the person having ordinary knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above embodiment can be naturally made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Therefore, the present invention should not be limited to the described embodiments, but should be the widest scope according to the technical idea defined by the claims.

DESCRIPTION OF SYMBOLS 1 Housing 2 Load / unload part 3 Polishing part 3A, 3B, 3C, 3D Polishing unit
4 Cleaning unit 5 Control unit 6 First linear transporter 7 Second linear transporter 10 Polishing pad 11 Lifter 12 Swing transporter 20 Front load unit 21 Traveling mechanism 22 Transfer robots 30A, 30B, 30C, 30D Polishing tables 31A, 31B, 31C, 31D Top ring 32A, 32B, 32C, 32D Polishing liquid supply nozzle 33A, 33B, 33C, 33D Dresser 34A, 34B, 34C, 34D Atomizer 36 Top ring shaft 40 Retainer ring 42 Elastic pad 51-56 Fluid path 60 Top ring Head 65 Air cylinder 67 Support shaft 72 Bearing 75 Pressure adjusting portion 85 Dresser arm 86 Dressing member 88 Oscillating shaft 90 Arm 94 Oscillating shaft 100 Tube 101 Pipe arm 102 Oscillating shafts 110 and 112 Water supply pipe 113 Distribution control unit 121-127 First to seventh transport hands 121a-127a Transport stages 130A-130C Lifting drive mechanisms 132A-132C Linear guides 134A-134C Horizontal drive mechanism 142 Air cylinder 143 Retainer ring station 149 Wear measuring device 150 Placement stage 151 Support arm 152 Elevating drive mechanism 162 Swing mechanism 165 Elevating drive mechanism 167 Reversing mechanism 170 Grip mechanism 180 Temporary placing table 190 First cleaning chamber 191 First transfer chamber 192 Second cleaning chamber 193 Second transfer chamber 194 Drying Chamber 201A, 201B Primary cleaning module 202A, 202B Secondary cleaning module 203 Temporary placing table 205A, 205B Drying module 209 First transport robot 210 Second transport robot 301-304 Rollers 307, 3 08 Roll sponge 321 Lifting drive mechanism 401 Base 402 Substrate support member 415 Motor 450 Rotating cover 454 Front nozzle 460,461 Nozzle 463 Back nozzle 464 Gas nozzle 470 Lift mechanism 481,482,483 Magnet 501 Bubbling tank 502 Bubbler 510 Water jacket

Claims (8)

A polishing section having a plurality of polishing units that respectively polish a plurality of substrates;
A transport mechanism for continuously transporting a plurality of substrates;
A substrate processing apparatus comprising a cleaning unit for cleaning and drying a polished substrate,
The cleaning unit includes a first distributes a plurality of juxtaposed washing line for cleaning a plurality of substrates in parallel, a plurality of substrates that are continuously conveyed by the conveying mechanism to one of said plurality of juxtaposed washing line Having 1 transfer robot and 2nd transfer robot,
The plurality of parallel cleaning lines include a plurality of primary cleaning modules for primary cleaning of the substrate and a plurality of secondary cleaning modules for secondary cleaning of the substrate. The next cleaning modules are arranged along the vertical direction,
The first transport robot moves up and down along a first support shaft extending in the vertical direction, and can access the plurality of primary cleaning modules and the plurality of secondary cleaning modules.
The second transfer robot moves up and down along a second support shaft extending in the vertical direction, and can access the plurality of secondary cleaning modules.
The substrate processing apparatus includes:
A detector for detecting a failure of the primary cleaning module and the secondary cleaning module;
When the detector detects a failure of any of the primary cleaning module and the secondary cleaning module, a control unit that selects a cleaning line that avoids the failed cleaning module and switches to the selected cleaning line further comprising a,
If any of the plurality of primary cleaning modules is cleaning the substrate or has failed, the control unit is not cleaning the substrate among the plurality of primary cleaning modules, or A substrate processing apparatus, wherein the first transfer robot is controlled to transfer a substrate to a primary cleaning module that is not faulty . The substrate processing apparatus according to claim 1, wherein the plurality of parallel cleaning lines include temporary placement tables on which substrates are temporarily placed. The substrate processing apparatus according to claim 1, wherein the cleaning unit includes a plurality of drying modules that dry the plurality of substrates cleaned by the plurality of parallel cleaning lines.   The substrate processing apparatus according to claim 3, wherein the plurality of drying modules are arranged along a vertical direction.   The first transfer robot has two upper and lower hands, the lower hand is used to transfer the substrate before cleaning, and the upper hand is used to transfer the substrate after cleaning. The substrate processing apparatus according to claim 1.   The substrate processing apparatus according to claim 1, wherein the second transfer robot has one hand for transferring the cleaned substrate. Polishing multiple substrates,
A plurality of polished substrates are continuously conveyed to a plurality of parallel cleaning lines composed of a plurality of primary cleaning modules and a plurality of secondary cleaning modules, and the primary cleaning module and the secondary cleaning module are respectively The substrates are arranged along the vertical direction, and the transfer of the substrate from the plurality of primary cleaning modules to the plurality of secondary cleaning modules is performed by a first transfer robot that can move up and down, and the plurality of secondary cleaning modules The substrate is unloaded from the second transfer robot that can move up and down.
Distributing the plurality of substrates to any of the plurality of parallel cleaning lines by the first transfer robot and the second transfer robot,
Cleaning the plurality of substrates in parallel in the plurality of parallel cleaning lines;
Drying the plurality of cleaned substrates;
When one of the primary cleaning module and the secondary cleaning module fails, a cleaning line that avoids the failed cleaning module is selected,
Switch to the selected cleaning line ,
If any of the plurality of primary cleaning modules is cleaning the substrate or has failed, the primary cleaning module of the plurality of primary cleaning modules has not been cleaned or has not failed. A substrate processing method comprising transporting a substrate to a cleaning module .   The substrate processing method according to claim 7, wherein the plurality of substrates are cleaned at a predetermined time difference.

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