JP6587379B2 - Polishing equipment - Google Patents

Description

The present invention relates to Migaku Ken apparatus, and more particularly to the chemical treatment of the substrate about the line UKen grinding apparatus among the previous step and polishing of a substrate such as a semiconductor wafer.

  In recent years, with higher integration and higher density of semiconductor devices, circuit wiring has become increasingly finer and the number of layers of multilayer wiring has increased. When trying to realize multilayer wiring while miniaturizing the circuit, the step becomes larger while following the surface unevenness of the lower layer, so as the number of wiring layers increases, the film coverage to the step shape in thin film formation (Step coverage) deteriorates. Therefore, in order to obtain a multi-layer wiring, it is necessary to improve the step coverage and perform a flattening process in an appropriate process. Further, since the depth of focus becomes shallower as the optical lithography becomes finer, it is necessary to planarize the surface of the semiconductor device so that the uneven steps on the surface of the semiconductor device are kept below the depth of focus.

Accordingly, in the semiconductor device manufacturing process, a planarization technique for the surface of the semiconductor device is becoming increasingly important. Among the planarization techniques, the most important technique is chemical mechanical polishing (CMP). This chemical mechanical polishing is performed using a polishing apparatus to polish a substrate such as a semiconductor wafer while supplying a polishing liquid (slurry) containing abrasive grains such as silica (SiO ₂ ) and ceria (CeO ₂ ) to the polishing pad. Polishing is performed by sliding on a polishing pad on a table.
The polishing apparatus polishes the semiconductor wafer (substrate) by the CMP process and cleans the wafer with a cleaning machine after polishing. In many cases, the polishing of the wafer is performed by multistage polishing such as two-stage polishing or three-stage polishing using two or more polishing tables, and also in this case, the wafer is cleaned by a cleaning machine after the final stage polishing. .

Japanese Patent Laid-Open No. 1-18228 Japanese Patent Laid-Open No. 2004-87760 JP 2005-277396 A Japanese Patent No. 3560051

The conventional polishing method and polishing apparatus described above have the following problems.
(1) A natural oxide film is formed on the film surface on the wafer before polishing, and at the initial stage of polishing, the polishing rate is low for removing the natural oxide film. The amount of processing is small. Further, in the Cu film polishing, there is a problem that in-plane uniformity results are affected because polishing spots are seen in the removal of the natural oxide film on the wafer surface.
(2) When polishing is performed with foreign matter adhering to the wafer before polishing, the foreign matter causes scratches on the wafer.
(3) After the first stage polishing, if the second stage polishing is performed with the slurry abrasive grains and components adhering to the wafer, the influence of the abrasive grains and chemical changes between the slurry (from alkaline to acidic, from acidic The product produced by (alkaline) causes scratches and defects on the wafer.
(4) After the second stage polishing, if the third stage polishing or buffing is performed with the slurry abrasive grains and components adhering to the wafer, the influence of the abrasive grains and chemical changes between the slurry (from alkaline to acidic) (From acidic to alkaline), scratches, contamination and reaction products are generated on the wafer.
(5) If the removal of slurry abrasive grains and components adhering to the wafer is insufficient after completion of the entire polishing process, it causes contamination of the cleaning member in the cleaning process, resulting in a decrease in cleaning ability and a decrease in the life of the cleaning member. Leads to. In addition, processing time is required to perform effective cleaning in the cleaning unit, which affects the throughput.

The present invention has been made in view of the above-described circumstances. When a substrate (wafer) is subjected to a plurality of stages of polishing using a plurality of polishing tables, foreign substances adhering in the preceding stage of the polishing process preventing bringing the cleaning process and to provide a can be Ru Migaku Ken apparatus.

In order to achieve the above-described object, a polishing apparatus of the present invention is a polishing apparatus that holds a substrate to be polished by a top ring and polishes the substrate by pressing the substrate against a polishing surface on a table. A plurality of tables to be processed are provided, and at least one of the plurality of tables is a chemical solution cleaning process dedicated table for performing a substrate cleaning process using a chemical solution.
According to an embodiment of the present invention, in a polishing method for polishing a substrate by pressing a substrate to be polished against a polishing surface on a table, when the substrate is subjected to a plurality of stages of polishing using a plurality of tables, A chemical cleaning process step for cleaning the substrate using a chemical solution is provided between the plurality of stages of polishing processing, and the chemical cleaning process step is a rotation provided on at least one of the plurality of rotatable tables. possible sponge, chemical supplies, intends rows chemical cleaning treatment by sliding contact with the substrate held by the top ring in the sponge.

  According to a preferred aspect of the present invention, there is provided a pre-polishing chemical solution treatment step for treating a substrate with a chemical solution before performing the plurality of stages of polishing treatment.

According to a preferred aspect of the present invention, there is provided a pre-cleaning chemical solution cleaning step for cleaning the substrate using a chemical solution after completion of the plurality of stages of all polishing processes and before cleaning by a cleaning machine. To do.
According to a preferred embodiment of the present invention, before Symbol pre-polishing chemical processing step and the pre-wash chemical cleaning step, the cleaning unit from the position or the top ring of the lower swing movement path of bets Ppuringu from position or polishing unit for attaching and detaching the substrate It implements in the position on the conveyance path | route which conveys to.

According to a preferred embodiment of the present invention, the swing range of the top ring of the multiple sets swing range so as to partially overlap, one cleaning unit or one chemical treatment below the position where the swing path of movement of the top ring overlaps A cleaning process step before and after polishing can be performed by installing a unit and performing cleaning processing or chemical processing on a substrate held on one or more top rings by the one cleaning unit or one chemical processing unit. In addition, at least one of the chemical treatment steps is performed.

According to a preferred aspect of the present invention, the pre-cleaning chemical cleaning step performed at a position on the transport path for transporting from the polishing unit to the cleaning unit holds the peripheral edge of the substrate and rotates the substrate while rotating the substrate. Or by scrubbing with a cleaning member while rotating the substrate while holding the peripheral edge of the substrate.
According to a preferred aspect of the present invention, chemical cleaning is performed with the substrate tilted by a tilt mechanism.

According to a preferred aspect of the present invention, the nozzle comprises a swingable nozzle or a two-fluid jet nozzle.
According to a preferred aspect of the present invention, the pre-cleaning chemical solution cleaning step performed at a position on a transport path for transporting from the polishing unit to the cleaning unit is performed by immersing the substrate in a chemical solution while the substrate is inclined. It is characterized by.

According to a preferred aspect of the present invention, the chemical solution cleaning dedicated table performs a substrate cleaning process using a chemical solution during the plurality of stages of polishing processing.
According to a preferred aspect of the present invention, the substrate is held by the top ring, and the substrate is subjected to a chemical cleaning process on the chemical cleaning process dedicated table.

According to a preferred aspect of the present invention, the chemical cleaning process dedicated table has at least one recess or tank for holding a chemical solution, and the substrate held by the top ring is used as the chemical solution held in the recess or the tank. A chemical cleaning process is performed by dipping.
According to a preferred aspect of the present invention, there are a plurality of the tanks on the chemical cleaning process dedicated table, and the plurality of tanks can hold different chemical liquids, respectively, or at least one chemical liquid and DIW. Can be held respectively.
According to a preferred aspect of the present invention, the chemical solution cleaning-dedicated table is capable of sequentially immersing the substrate held by the top ring in the chemical solution or DIW in the plurality of tanks by repeatedly rotating and stopping. It is characterized by being.

  According to a preferred aspect of the present invention, the top ring includes a top ring main body having a membrane for holding the substrate, and a retainer ring fixed to the top ring main body and disposed so as to surround the outer peripheral edge of the substrate. The retainer ring has grooves on the lower surface of the retainer ring that are spaced apart from each other to allow the chemical solution to flow into the lower surface of the substrate, and the top ring body receives the chemical solution that has flowed into the lower surface of the substrate. The groove provided on the lower surface of the retainer ring having a port for discharging is set so that the number of grooves in the part far from the port is larger than the number of grooves in the part near the port. It is characterized by being.

According to a preferred aspect of the present invention, the temporary placement table provided at a position on the transport path for transporting from the polishing unit to the cleaning unit includes a cleaning mechanism for cleaning the substrate after polishing with the cleaning mechanism, A rotation mechanism that rotates while holding the outer periphery of the substrate, a tilt mechanism that tilts the rotation mechanism, and a nozzle that is disposed above the substrate tilted by the tilt mechanism and injects a chemical liquid onto the substrate. And
According to a preferred aspect of the present invention, the nozzle comprises a swingable nozzle or a two-fluid jet nozzle.
According to a preferred aspect of the present invention, there is provided a cleaning mechanism that is installed outside the plurality of polishing tables and that performs chemical cleaning on the polished substrate, the cleaning mechanism holding and tilting the substrate, and the substrate An immersion mechanism for immersing the substrate in a chemical solution in an inclined state and a chemical solution supply unit that is disposed above the inclined substrate and supplies the chemical solution to the substrate are provided.

The present invention has the following effects.
(1) Elimination of abrasives and components adhering to the wafer (substrate) after the first stage polishing eliminates the occurrence of wafer scratches and defects during the second stage polishing. Can do.
(2) By removing the abrasive grains and components adhering to the wafer (substrate) after the second stage polishing, the generation of scratches and defects in the wafer during the third stage polishing or buffing process. It can be lost.
(3) By performing the process for removing the natural oxide film at the stage before the main polishing, the wafer processing capability (WPH) can be improved. In addition, the in-plane uniformity can be accurately evaluated by removing the oxide film in advance.
(4) By performing a cleaning step for removing foreign substances adhering to the wafer surface (substrate surface) before the main polishing, it is possible to eliminate the generation of scratches on the wafer.
(5) By performing a process for wafer cleaning (substrate cleaning) on the final table after polishing, contamination of the cleaning member in the cleaning process can be reduced. In addition, the cleaning time in the cleaning unit can be shortened by performing the initial cleaning.

FIG. 1 is a plan view showing an overall configuration of a polishing apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view schematically showing the first polishing unit. FIGS. 3A and 3B are diagrams showing details of the cleaning unit shown in FIG. 1, FIG. 3A is a plan view, and FIG. 3B is a side view. FIG. 4A is a flowchart illustrating an example of a wafer processing process by the polishing apparatus configured as illustrated in FIGS. 1 to 3. FIG. 4B is a flowchart illustrating an example of a wafer processing process performed by the polishing apparatus configured as illustrated in FIGS. 1 to 3. FIG. 5A is a flowchart showing another example of the wafer processing process by the polishing apparatus configured as shown in FIGS. FIG. 5B is a flowchart showing another example of the wafer processing step by the polishing apparatus configured as shown in FIGS. 1 to 3. FIGS. 6A to 6F are schematic views illustrating an example of a process for performing chemical treatment of a wafer on a table. FIGS. 7A to 7F are schematic views showing other examples of a process for performing chemical treatment of a wafer on a table. FIGS. 8A to 8F are schematic views showing still another example of a process of cleaning a wafer with a chemical solution on a table. FIGS. 9A to 9F are schematic views showing still another example of a process for performing chemical treatment of a wafer on a table. FIGS. 10A and 10B are views showing a configuration of a top ring suitable for performing chemical treatment of a wafer on a table. FIG. 10A is a longitudinal sectional view of the top ring, and FIG. ) Is a plan view of a retainer ring provided on the top ring. FIGS. 11A, 11B, and 11C are schematic views showing a configuration for performing chemical treatment of a wafer at a position other than the table position and the wafer attaching / detaching position. FIGS. 12A and 12B are views showing a mode in which a cleaning nozzle for cleaning chemicals is provided between the linear transporter and the table. FIG. 12A is a plan view, and FIG. These are the XII arrow directional views of Fig.12 (a). FIG. 12C is a plan view showing an example in which the wafer held on the adjacent top ring is cleaned by one cleaning unit at a position below the swing movement path of the top ring. FIGS. 13A and 13B are views showing a mode in which a cleaning nozzle for cleaning chemicals is provided on a linear transporter that functions as a wafer attachment / detachment position. FIG. 13A is a plan view, and FIG. FIG. 13B is a view taken along arrow XIII in FIG. 14 (a) and 14 (b) are views showing a mode in which a chemical cleaning sponge is provided between the linear transporter and the table, FIG. 14 (a) is a plan view, and FIG. 14 (b) is a plan view. FIG. 14A is a view taken in the direction of arrow XII in FIG. 14A, and FIG. 14C is a diagram illustrating an aspect in which a chemical solution cleaning sponge is provided on the table. FIGS. 15A, 15B, and 15C are schematic views illustrating an example of a configuration for performing chemical treatment of a wafer at a temporary placement table position. FIGS. 16A, 16B, and 16C are schematic views showing another example of a configuration for performing chemical treatment of a wafer at a temporary placement table position. FIGS. 17A, 17B, and 17C are schematic views showing still another example of a configuration for performing chemical treatment of a wafer at a temporary placement table position.

Hereinafter, embodiments of a polishing method and a polishing apparatus according to the present invention will be described 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 an overall configuration of a polishing apparatus according to an embodiment of the present invention. As shown in FIG. 1, this polishing apparatus includes a substantially rectangular housing 1, and the interior of the housing 1 is divided into a load / unload section 2, a polishing section 3, and a cleaning section 4 by partition walls 1a and 1b. Has been. The load / unload unit 2, the polishing unit 3, and the cleaning unit 4 are assembled independently and exhausted independently. Further, the polishing apparatus has a control unit 5 that controls the wafer 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 polishing 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, and the upper hand is used when returning the processed wafer to the wafer cassette, and the lower hand is used when removing the wafer before processing from the wafer cassette. Then, you can use the upper and lower hands properly. Further, 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 inside of the load / unload unit 2 is at a higher pressure than any of the polishing apparatus outside, the polishing unit 3, and the cleaning unit 4. 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 polishing 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.

  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 the positions TP7).

  The wafer is transferred to the polishing units 3A and 3B by the first linear transporter 6. 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. Accordingly, 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 is moved between the polishing position and the third transfer position TP3 by the swing operation of the top ring head 60, and the delivery of the wafer to the top ring 31B is performed at the third transfer position. Performed at TP3. The top ring 31C of the third polishing unit 3C moves between the polishing position and the sixth transfer position TP6 by the swing operation of the top ring head 60, and the wafer is transferred to the top ring 31C at the sixth transfer position TP6. Is called. The top ring 31D of the fourth polishing unit 3D is moved between the polishing position and the seventh transfer position TP7 by the swing operation of the top ring head 60, and the wafer is transferred to the top ring 31D at the seventh transfer position TP7. Is called.

  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 in the partition wall 1a between the lifter 11 and the transfer robot 22, and when transferring the wafer, 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. Further, the wafer polished by the polishing unit 3 is transferred to the cleaning unit 4 via the swing transporter 12.

  On the side of the swing transporter 12, a temporary placement table 180 for a wafer W installed on 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.

  3 (a) and 3 (b) are diagrams showing details of the cleaning unit 4 shown in FIG. 1, FIG. 3 (a) is a plan view, and FIG. 3 (b) is a side view. As shown in FIGS. 3A and 3B, 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.

  Between the upper secondary cleaning module 202A and the lower secondary cleaning module 202B, a temporary wafer placement table 203 is provided. 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. 3A, 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 moves 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 adhered), 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” refers to a movement path when one wafer is cleaned by a plurality of cleaning modules inside the cleaning unit 4. For example, one wafer is transferred in the order of the first transfer robot 209, the upper primary cleaning module 201A, the first transfer robot 209, the upper secondary cleaning module 202A, the second transfer robot 210, and the upper drying module 205A. In parallel with the other wafers, 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 transported in order. 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, which deteriorates 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.

  Slurry adheres 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 if the preceding wafer is cleaned by either the upper primary cleaning module 201A or the lower primary cleaning module 201B, The wafer can be loaded into the primary cleaning module and cleaned. Accordingly, not only high throughput can be realized, but also the polished wafer can be immediately cleaned to prevent copper corrosion.

  If only the primary cleaning is necessary, the wafer is transferred in the order of 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 the upper drying module 205A. The secondary cleaning in the second cleaning chamber 192 can be omitted. Further, 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.

Next, a wafer processing process performed by the polishing apparatus configured as shown in FIGS. 1 to 3 will be described with reference to FIGS. 4A and 4B and FIGS. 5A and 5B. In the following description, the polishing tables 30A, 30B, 30C, and 30D shown in FIG. 1 may be subjected only to the chemical treatment process and the cleaning process without performing the polishing process, so that the tables 30A, 30B, 30C, and 30D are simply Called.
4A and 4B are flowcharts showing an example of a wafer processing process by the polishing apparatus configured as shown in FIGS. 1 to 3. As shown in FIG. 4A, the wafer processing is started, and the wafer taken out from the wafer cassette of the front load unit 20 is transferred (moved) to the first polishing unit 3A by the transfer mechanism (step S1). The wafer transferred to the first polishing unit 3A is held on the lower surface of the top ring 31A by vacuum suction (step S2). The wafer held by the top ring 31A is processed by one of the following three steps.

(1) First Processing Step The top ring 31A holding the wafer moves from the position of the first linear transporter 6 to the position of the table 30A (step S3-1), and the top ring 31A descends (step S3-2). The wafer is subjected to chemical polishing (step S3-3A) or Dip processing (step S3-3B) on the table 30A. After the processing, the top ring moves up (step S3-4), and the top ring 31A moves from the position of the table 30A to the position of the first linear transporter 6 (step S3-5).
(2) Second Processing Step The top ring 31A holding the wafer moves from the position of the first linear transporter 6 to the processing position (step S3-1). The processing position is a position other than the table position and the wafer attachment / detachment position (described later). The wafer is cleaned (step S3-2A) or Dip processing (step S3-2B) at the processing position, and the top ring 31A moves from the processing position to the position of the first linear transporter 6 after the processing (step S3-3).
(3) Third Processing Step The wafer held by the top ring 31A is cleaned (Step S3-1A) or Dip processing (Step S3-1B) at the wafer attachment / detachment position.

  The wafer that has completed any of the first to third processing steps is detached from the top ring 31A (step S4). Thereafter, the wafer is transferred (moved) from the first polishing unit 3A to the second polishing unit 3B by the transfer mechanism (step S5). In the second polishing unit 3B, the wafer is held on the lower surface of the top ring 31B by vacuum suction (step S6). The top ring 31B holding the wafer moves from the position of the first linear transporter 6 to the position of the table 30B (step S7), and the top ring 31B descends (step S8). The wafer held by the top ring 31B is pressed against the polishing pad 10 on the table 30B and polished in the first stage (step S9). When the first stage polishing is completed, the top ring 31B moves up (step S10), and then the top ring 31B moves from the processing position to the position of the first linear transporter 6 (step S11). At the position of the first linear transporter 6, the wafer is detached from the top ring 31B (step S12). Next, the wafer is transferred (moved) from the second polishing unit 3B to the third polishing unit 3C by the transfer mechanism (step S13).

  As shown in FIG. 4B, the wafer transferred to the third polishing unit 3C is held on the lower surface of the top ring 31C by vacuum suction (step S14). The top ring 31C holding the wafer moves from the position of the second linear transporter 7 to the position of the table 30C (step S15), and the top ring 31C descends (step S16). The wafer held by the top ring 31C is pressed against the polishing pad 10 on the table 30C and polished in the second stage (step S17). When the second stage polishing is completed, the top ring 31C is raised (step S18), and then the top ring 31C is moved from the processing position to the position of the second linear transporter 7 (step S19). At the position of the second linear transporter 7, the wafer is detached from the top ring 31C (step S20). Next, the wafer is transferred (moved) from the third polishing unit 3C to the fourth polishing unit 3D by the transfer mechanism (step S21).

  As shown in FIG. 4B, the wafer transferred to the fourth polishing unit 3D is held on the lower surface of the top ring 31D by vacuum suction (step S22). The top ring 31D holding the wafer moves from the position of the second linear transporter 7 to the position of the table 30D (step S23), and the top ring 31D descends (step S24). The wafer held by the top ring 31D is polished (step S25A) or buffed (step S25B) at the third stage on the table 30D. After the processing, the top ring moves up (step S26), and the top ring 31D moves from the processing position to the position of the second linear transporter 7 (step S27). The wafer is detached from the top ring 31D at the position of the second linear transporter 7 (step S28). The polished wafer detached from the top ring 31D is transferred from the fourth polishing unit 3D to the cleaning machine (step S29). Thereafter, the wafer is cleaned by a plurality of cleaning modules 201A, 201B, 202A, 202B (step S30). The cleaned wafer is transferred (moved) by the transfer mechanism and returned to the wafer cassette of the front load unit 20 (step S31). In this way, the wafer processing is completed.

  5A and 5B are flowcharts showing another example of the wafer processing process by the polishing apparatus configured as shown in FIGS. As shown in FIG. 5A, the wafer processing is started, and the wafer taken out from the wafer cassette of the front load unit 20 is transferred (moved) to the first polishing unit 3A by the transfer mechanism (step S1). The wafer transferred to the first polishing unit 3A is held on the lower surface of the top ring 31A by vacuum suction (step S2). The top ring 31A holding the wafer moves to the position of the table 30A (step S3), and the top ring 31A descends (step S4). The wafer is polished on the table 30A using an acidic slurry (step S5A) or using an alkaline slurry (step S5B). The polished wafer is water-polished (step S6). In the water polish, the wafer is cleaned by sliding the wafer against the polishing pad 10 while supplying DIW onto the polishing pad 10, and it is not necessary to completely remove deposits on the wafer. Can be done shortly. Thereafter, the top ring 31A moves up (step S7), and the top ring 31A moves to the position of the first linear transporter 6 (step S8). At the position of the first linear transporter 6, the wafer is detached from the top ring 31A (step S9). Next, the wafer is transferred (moved) from the first polishing unit 3A to the second polishing unit 3B by the transfer mechanism (step S10).

  As shown in FIG. 5A, the wafer conveyed (moved) to the second polishing unit 3B is held by vacuum suction on the lower surface of the top ring 31B (step S11). The wafer held by the top ring 31B is processed by one of the following three steps.

(1) First Processing Step The top ring 31B holding the wafer moves from the position of the first linear transporter 6 to the position of the table 30B (step S12-1), and the top ring 31B descends (step S12-2). The wafer held by the top ring 31B is cleaned on the table 30B using a chemical solution and DIW (step S12-3). After cleaning, the top ring 31B moves up (step S12-4), and the top ring 31B moves from the position of the table 30B to the position of the first linear transporter 6 (step S12-5).
(2) Second Processing Step The top ring 31B holding the wafer moves from the position of the first linear transporter 6 to the processing position (step S12-1). The processing position is a position other than the table position and the wafer attachment / detachment position (described later). At the processing position, the wafer is cleaned using a chemical solution and DIW (step S12-2). After the processing, the top ring 31B moves from the processing position to the position of the first linear transporter 6 (step S12-3).
(3) Third Processing Step The wafer held by the top ring 31B is cleaned using a chemical solution and DIW at the wafer attachment / detachment position (step S12-1).

  The wafer that has completed any of the first to third processing steps is detached from the top ring 31B (step S13). Thereafter, the wafer is transferred (moved) from the second polishing unit 3B to the third polishing unit 3C by the transfer mechanism (step S14).

  As shown in FIG. 5B, the wafer transferred to the third polishing unit 3C is held on the lower surface of the top ring 31C by vacuum suction (step S15). The top ring 31C holding the wafer moves to the processing position (step S16), and the top ring 31C is lowered (step S17). The wafer is polished on the table 30C using an alkaline slurry (step S18A) or using an acidic slurry (step S18B). After polishing, the top ring 31C moves up (step S19), and the top ring 31C moves to the position of the second linear transporter 7 (step S20). The wafer is detached from the top ring 31C at the position of the second linear transporter 7 (step S21). The polished wafer detached from the top ring 31C is transferred from the third polishing unit 3C to the cleaning machine (step S22). Thereafter, the wafer is cleaned by a plurality of cleaning modules 201A, 201B, 202A, 202B (step S23). The cleaned wafer is transferred (moved) by the transfer mechanism and returned to the wafer cassette of the front load unit 20 (step S24). In this way, the wafer processing is completed.

FIGS. 6A to 6F are schematic views illustrating an example of a process for performing chemical treatment of a wafer on a table. 6A to 6F is applied to the Dip processing (step S3-3B) of the first processing step in FIG. 4A. In the following description, the case of the table 30A of the first polishing unit 3A will be described, but other tables 30B, 30C, and 30D may be used.
Fig.6 (a) is typical sectional drawing of the table for chemical | medical solution processing. As shown in FIG. 6A, the table 30 </ b> A is fixed by a table fixing ring 13. The ring-shaped guide 14 is attached to the outside of the table 30A, and the polishing pad 10 is attached to the upper surface of the table 30A and the upper surface of the ring-shaped guide 14. The upper surface of the ring-shaped guide 14 is an inclined surface 14a that is inclined obliquely upward from the inside in the radial direction toward the outside. In FIG. 6A, the ring-shaped guide 14 is shown as a perspective view on the right side. In a state where the ring-shaped guide 14 is attached to the outside of the table 30A, the inner diameter portion of the ring-shaped guide 14 is equal to the height of the table 30A, and the outer peripheral portion of the ring-shaped guide 14 is higher than the table 30A. Therefore, when a chemical solution is supplied from the chemical solution supply nozzle 15 to the upper surface of the polishing pad 10, the outer peripheral portion of the ring-shaped guide 14 is high, so that the chemical solution can be held on the polishing pad surface portion. The chemical solution Dip is performed by immersing the wafer W held by the top ring 31A in the held chemical solution portion.

  FIGS. 6B to 6F are diagrams showing steps in the case of performing a chemical treatment using the table 30A having the configuration shown in FIG. As shown in FIG. 6B, a chemical solution is supplied onto the polishing pad 10 from the chemical solution supply nozzle 15. When the concave portion of the polishing pad 10 is filled with the chemical solution by supplying the chemical solution from the chemical solution supply nozzle 15, the top ring 31A that adsorbs the wafer W is moved to the processing position as shown in FIG. Next, as shown in FIG. 6 (d), the top ring 31A is lowered, and the wafer W is dipped (immersed) in the chemical solution. At this time, the table 30A and the top ring 31A are not rotated. The wafer W is attracted to the top ring 31 </ b> A, and the wafer W is processed while being lifted from the polishing pad 10. When the chemical processing is completed, as shown in FIG. 6E, the top ring 31A is raised, the wafer W is moved to the wafer attaching / detaching position, and the wafer after the chemical processing is detached from the top ring 31A to the next step. Transport. When the top ring 31A is raised, as shown in FIG. 6 (f), the table 30A is rotated, and the chemical solution filled on the polishing pad is removed from the table through the inclined surface of the outer peripheral portion of the polishing pad 10 by centrifugal force. To discharge. During the next wafer processing, the rotation of the table 30A is stopped, and the chemical processing shown in FIGS. 6B to 6F is similarly performed.

FIGS. 7A to 7F are schematic views showing other examples of a process for performing chemical treatment of a wafer on a table. 7A to 7F is applied to the Dip processing (step S3-3B) of the first processing step in FIG. 4A.
Fig.7 (a) is typical sectional drawing of the table for chemical | medical solution processing. As shown in FIG. 7A, a guide 16 made of a disc having an H-shaped cross section is attached on the table 30A. At this time, the guide 16 covers the surface of the table 30A. The upper surface of the outer periphery of the guide 16 is an inclined surface 16a that is inclined obliquely upward from the inside in the radial direction toward the outside. In FIG. 7A, the guide 16 is shown as a perspective view on the right side. When the chemical solution is supplied from the chemical solution supply nozzle 15 to the upper surface of the guide 16, the chemical solution can be held. The chemical solution Dip is performed by immersing the wafer W held by the top ring 31A in the held chemical solution portion.

  FIGS. 7B to 7F are diagrams showing steps in the case of performing a chemical treatment using the table 30A having the configuration shown in FIG. As shown in FIG. 7B, the chemical liquid is supplied onto the guide 16 from the chemical liquid supply nozzle 15. When the concave portion of the guide 16 is filled with the chemical solution by supplying the chemical solution from the chemical solution supply nozzle 15, the top ring 31A that has adsorbed the wafer W is moved to the processing position as shown in FIG. Next, as shown in FIG. 7D, the top ring 31A is lowered, and the wafer is dipped (immersed) in the chemical solution. At this time, the table 30A and the top ring 31A are not rotated. The wafer W is in a state of being attracted to the top ring 31 </ b> A, and the wafer W is processed while being lifted from the upper surface of the guide 16. When the chemical processing is completed, as shown in FIG. 7E, the top ring 31A is raised, the wafer W is moved to the wafer attaching / detaching position, and the wafer after the chemical processing is detached from the top ring 31A to the next step. Transport. When the top ring 31A is raised, the table 30A is rotated as shown in FIG. 7 (f), and the chemical solution filled on the guide 16 is discharged out of the table through the inclined surface 16a by centrifugal force. At the time of the next wafer processing, the rotation of the table 30A is stopped, and the chemical solution processing shown in FIGS.

FIGS. 8A to 8F are schematic views showing still another example of a process of cleaning a wafer with a chemical solution on a table. 8A to 8F is applied to the Dip process (step S3-3B) of the first process step in FIG. 4A.
Fig.8 (a) is typical sectional drawing of the table for chemical | medical solution processing. As shown in FIG. 8A, a guide 17 made of a disk having an H-shaped cross section is attached on the table 30A. At this time, the guide 17 covers the surface of the table 30A. In FIG. 8A, a guide 17 is shown as a perspective view on the right side. When the chemical solution is supplied from the chemical solution supply nozzle 15 to the upper surface of the guide 17, the chemical solution can be held. The chemical solution Dip is performed by immersing the wafer W held by the top ring 31A in the held chemical solution portion.

  FIGS. 8B to 8F are diagrams showing steps in the case of performing a chemical treatment using the table 30A having the configuration shown in FIG. As shown in FIG. 8B, the chemical solution is supplied from the chemical solution supply nozzle 15 onto the guide 17. When the concave portion of the guide 17 is filled with the chemical solution by supplying the chemical solution from the chemical solution supply nozzle 15, as shown in FIG. 8C, the top ring 31A that has adsorbed the wafer W is moved to the processing position. Next, as shown in FIG. 8D, the top ring 31A is lowered, and the wafer is dipped (immersed) in the chemical solution. At this time, the table 30A and the top ring 31A are not rotated. The wafer W is in a state of being attracted to the top ring 31 </ b> A, and the wafer W is processed while being lifted from the upper surface of the guide 17. When the chemical processing is completed, as shown in FIG. 8E, the top ring 31A is raised, the wafer W is moved to the wafer attaching / detaching position, and the wafer after the chemical processing is detached from the top ring 31A to the next step. Transport. When the top ring 31A is raised, as shown in FIG. 8 (f), the chemical solution supply nozzle 15 is lowered, and the chemical solution filled on the guide 17 is sucked by a pump or the like using the chemical solution supply nozzle 15 to remove it from the table. To discharge. The chemical treatment shown in FIGS. 8B to 8F is similarly performed on the next wafer.

FIGS. 9A to 9F are schematic views showing still another example of a process for performing chemical treatment of a wafer on a table. 9A to 9F is applied to the cleaning process (step S12-3) using the chemical liquid and DIW in the first processing process of FIG. 5A.
Fig.9 (a) is typical sectional drawing of the table for chemical | medical solution processing. As shown in FIG. 9A, a disk-shaped base 18 is fixed on the table 30 </ b> B, and a plurality of cylindrical container-shaped Dip tanks 19 are provided on the base 18. In the following, when a plurality of Dip tanks need to be distinguished from each other, they will be described using subscripts 1, 2, and 3. As shown in FIG.9 (b), in this embodiment, the three Dip tanks which consist of the 1st Dip tank 19-1, the 2nd Dip tank 19-2, and the 3rd Dip tank 19-3 are provided. In addition, although the cylindrical container-shaped Dip tank is illustrated in the illustrated example, it may be divided into two or more Dip tanks by a partition. When the wafer held by the top ring 31B is immersed in the Dip tank 19, the table 30B is rotated and the angle of the table 30B is positioned by the positioning mechanism, and then the top ring 31B is lowered to select any of the plurality of Dip tanks. Can be selected.

  FIGS. 9B to 9F are diagrams showing steps in the case of performing chemical treatment using the table having the configuration shown in FIG. As shown in FIG. 9B, the first chemical liquid is supplied from the chemical liquid supply nozzle 15 to the first Dip tank 19-1. When the first dip tank 19-1 is filled with the chemical solution by supplying the chemical solution from the chemical solution supply nozzle 15, as shown in FIG. 9C, the top ring 31B that has adsorbed the wafer W is moved to the processing position, and the table 30B. Is rotated (120 degrees) to the position of the first chemical treatment. Next, as shown in FIG. 9D, the top ring 31B is lowered to dip (immerse) the wafer in the first chemical solution in the first Dip tank 19-1. At this time, the table 30B and the top ring 31B are not rotated. The wafer W is in a state of being attracted to the top ring 31B, and the wafer W is processed in a state where it is floated from the bottom surface of the Dip tank. At this time, DIW is supplied from the chemical solution supply nozzle 15 to the second Dip tank 19-2. When the chemical processing is completed, as shown in FIG. 9E, the top ring 31B is raised, the table 30B is rotated (120 degrees), and the second Dip tank 19-2 is moved to the processing position. Next, as shown in FIG. 9 (f), the top ring 31B is lowered, and the top ring 31B is rotated around its own axis while the wafer is immersed in DIW in the second Dip tank 19-2, so that the wafer is removed. Wash. On the other hand, in the first Dip tank 19-1, the chemical liquid discharge nozzle 23 is lowered to discharge the first chemical liquid in the first Dip tank 19-1. Further, the second chemical liquid is supplied from the chemical liquid supply nozzle 15 to the third Dip tank 19-3. Thereafter, the top ring 31B is once raised, and the table 30B is rotated (120 degrees) to the position of the second chemical treatment. Thereafter, the top ring 31B is lowered, and the wafer is dipped (immersed) in the second chemical solution.

FIGS. 10A and 10B are views showing a configuration of a top ring suitable for performing chemical treatment of a wafer on a table. FIG. 10A is a longitudinal sectional view of the top ring, and FIG. ) Is a plan view of a retainer ring provided on the top ring. The process of performing chemical treatment on a wafer using the top ring shown in FIGS. 10A and 10B is applied to the cleaning process (step S12-3) using the chemical and DIW in the first treatment process of FIG. 5A.
As shown in FIG. 10A, the top ring 31 </ b> B includes a substantially disc-shaped top ring main body 32, and a retainer ring 33 is fixed to the lower surface of the outer periphery of the top ring main body 32. A membrane 34 is stretched on the lower surface of the top ring body 32 at a position on the inner side in the radial direction of the retainer ring 33, and a pressure chamber 35 is formed between the membrane 34 and the lower surface of the top ring body 32.
As shown in FIG. 10B, a large number of grooves 33 g are formed on the lower surface of the retainer ring 33. As shown in FIG. 10A, the top ring body 32 is provided with a discharge port 32 </ b> P that communicates with the space between the inner peripheral surface of the top ring main body 32 and the outer peripheral surface of the membrane 34. The discharge port 32P is connected to a vacuum source (Vac). As shown in FIG. 10 (b), the retainer ring grooves 33g are not arranged at equal intervals, but a portion close to the discharge port 32P is sparse and a portion far from the discharge port 32P is densely arranged.

  When chemical processing of a wafer is performed by the top ring 31B configured as shown in FIGS. 10A and 10B, the membrane 34 is raised by setting the pressure chamber 35 to a negative pressure, and the wafer is lifted from the upper surface of the table. By making it up, the chemical solution can easily hit the wafer surface. The retainer ring 33 is provided with a large number of retainer ring grooves 33g on the lower surface, and the retainer ring grooves 33g are not arranged at regular intervals but densely arranged at a portion far from the discharge port 32P. Therefore, the chemical solution is efficiently drawn in from a large number of retainer ring grooves 33g formed in a portion far from the discharge port 32P and is brought into contact with the wafer surface while being sucked by the negative pressure from the discharge port 32P toward the discharge port 32P. Then, the air is quickly discharged from the discharge port 32P on the side where the number of the retainer ring grooves 33g is small. Thereby, inflow of the chemical liquid to the wafer surface and discharge of the chemical liquid after processing can be promoted, and the etching effect can be enhanced.

FIGS. 11A, 11B, and 11C are schematic views showing a configuration for performing chemical treatment of a wafer at a position other than the table position and the wafer attaching / detaching position. The positions other than the table position and the wafer attachment / detachment position are, for example, positions below the moving path of the top ring that performs the swing operation. 11 (a), 11 (b), and 11 (c) are the same as the cleaning (step S3-2A) or Dip processing (step S3-2B) in the second processing step of FIG. 4A and the second processing step of FIG. 5A. This is applied to the cleaning (step S12-2). 11A, 11B, and 11C show a case where the present invention is applied to the second processing step in FIG. 4A.
FIG. 11A is a perspective view showing an aspect provided with a bowl-shaped treatment tank 41 for cleaning chemicals. As shown in FIG. 11 (a), a supply pipe 42 is connected to the bottom surface of the bowl-shaped treatment tank 41, and the mixing ratio (dilution rate) and flow rate from the bottom surface of the bowl-shaped treatment tank 41 by the supply pipe 42. It is possible to supply a liquid mixture of a chemical solution and DIW that can be freely changed. In addition, you may supply the chemical | medical solution and DIW which each can adjust a flow volume by another system | strain. As shown in FIG. 11A, the top ring 31A is lowered in a state where the liquid mixture of the chemical liquid and DIW is filled in the bowl-shaped processing tank 41, and the wafer is dip (immersed) in the liquid mixture of the chemical liquid and DIW. Thus, the chemical cleaning process can be performed.

  FIG. 11B is a perspective view showing an aspect provided with a bowl-shaped treatment tank 43 for cleaning chemicals. As shown in FIG. 11 (b), a bowl-shaped treatment tank 43 which is an upright guide 43g, 43g by bending both ends of a flat plate is arranged inclined downward. A supply pipe 44 is disposed at one end of the bowl-shaped processing tank 43, and a chemical liquid and DIW mixed liquid whose mixing ratio (dilution rate) and flow rate can be freely changed are supplied to the processing tank 43 through the supply pipe 44. Be able to. In addition, you may supply the chemical | medical solution and DIW which can adjust flow volume by another system, respectively. The mixed solution of the chemical solution and DIW supplied to one end side of the bowl-shaped treatment tank 43 flows to the other end side along the inclined surface of the bowl-shaped treatment tank 43. As shown in FIG. 11 (b), the top ring 31A is lowered in a state where the liquid mixture of the chemical liquid and DIW is poured into the bowl-shaped processing tank 43, and the wafer is dipped (immersed) in the liquid mixture of the chemical liquid and DIW. Thus, the chemical cleaning process can be performed.

  FIG.11 (c) is a perspective view which shows the aspect provided with the nozzle 45 for chemical | medical solution washing | cleaning. As shown in FIG. 11 (c), a nozzle 45 having a nozzle port facing upward is provided, and a liquid mixture of a chemical solution and DIW is supplied to the nozzle 45 from a supply pipe 46. When the top ring 31A holding the wafer is positioned above the nozzle 45, a liquid mixture of DIW and DIW that can freely change the mixing ratio (dilution ratio) and flow rate is sprayed from the nozzle 45 toward the wafer. A chemical cleaning process can be performed. In addition, you may inject | pour the chemical | medical solution and DIW which can adjust flow volume by another system, respectively.

  FIGS. 12A and 12B are views showing a mode in which a cleaning nozzle for cleaning chemicals is provided between the linear transporter and the table. FIG. 12A is a plan view, and FIG. These are the XII arrow directional views of Fig.12 (a). The configuration shown in FIGS. 12A and 12B is applied to the cleaning in the second processing step in FIG. 4A (step S3-2A) and the cleaning in the second processing step in FIG. 5A (step S12-2). FIGS. 12A and 12B show a case where the present invention is applied to the second processing step of FIG. 4A. As shown in FIGS. 12A and 12B, a cleaning nozzle 47 is provided between the first linear transporter 6 and the table 30A. The cleaning nozzle 47 is configured by forming a plurality of nozzle holes 48h on the upper surface of a rectangular cylindrical main body portion 48, and the main body portion 48 has a length substantially the same as the diameter of the top ring 31A in the horizontal direction. It extends to. The cleaning nozzle 47 is disposed below the moving path of the top ring that moves by the swing operation of the top ring head 60. The top ring 31A stops above the cleaning nozzle 47 while moving between the first linear transporter 6 and the table 30A. During this stop, the liquid mixture of DIW and DIW is sprayed from the cleaning nozzle 47 to perform chemical cleaning of the wafer. It is supposed to be. While the liquid mixture of the chemical liquid and DIW is sprayed from the cleaning nozzle 47 toward the wafer, the top ring 31A rotates around its own axis so that the entire surface of the wafer is cleaned with the chemical liquid.

FIG. 12C is a plan view showing an example in which the wafer held on the adjacent top ring is cleaned by one cleaning unit at a position below the swing movement path of the top ring. The example shown in FIG. 12 (c) shows a mode in which a chemical solution cleaning unit is provided between two adjacent tables 30A (or 30C) and 30B (or 30D), but there are two adjacent tables and a linear transporter. A chemical solution cleaning unit may be provided between them. In FIG. 12C, a cleaning nozzle 47 is provided as a chemical cleaning unit. The configuration of the cleaning nozzle 47 and the cleaning method using the cleaning nozzle 47 are as described in the description of FIG. Moreover, you may install a chemical processing unit in the location of a chemical cleaning unit.
In this way, by setting the swing range so that the swing ranges of the adjacent top rings partially overlap, one cleaning unit or one chemical treatment unit is installed below the position where the swing movement paths of the top rings overlap. It is possible to perform a cleaning process or a chemical process on a wafer held on one or more top rings.

  FIGS. 13A and 13B are views showing a mode in which a cleaning nozzle for cleaning a chemical solution is provided at the position of the linear transporter functioning as a wafer attaching / detaching position. FIG. 13A is a plan view and FIG. FIG. 13B is a view taken along arrow XIII in FIG. The configuration shown in FIGS. 13A and 13B is applied to the cleaning in the third processing step in FIG. 4A (step S3-1A) and the cleaning in the third processing step in FIG. 5A (step S12-1). FIGS. 13A and 13B show a case where it is applied to the third processing step of FIG. 4A. As shown in FIGS. 13A and 13B, a cleaning nozzle 49 is provided at the position of the first linear transporter 6. The cleaning nozzle 49 is configured by fixing a plurality of cleaning nozzles 51 on the upper surface of the rectangular parallelepiped main body 50. The plurality (two in the illustrated example) of the cleaning nozzles 51 fan-shaped a mixture of a chemical solution and DIW. It is configured to spray toward the wafer so as to spread. The top ring 31A swings from the table side to the linear transporter side, and when the top ring 31A is stopped on the linear transporter side, the liquid mixture of DIV and DIW is sprayed from the cleaning nozzle 51 to perform chemical cleaning of the wafer. ing. While the liquid mixture of the chemical liquid and DIW is sprayed from the cleaning nozzle 51 toward the wafer, the top ring 31A rotates around its own axis, whereby the entire surface of the wafer is cleaned with the chemical liquid.

  FIGS. 14A and 14B are views showing a mode in which a chemical cleaning sponge 52 is provided between the linear transporter and the table. FIG. 14A is a plan view, and FIG. FIG. 15 is a view on arrow XIV in FIG. The configuration shown in FIGS. 14A and 14B is applied to the cleaning in the second processing step of FIG. 4A (step S3-2A) and the cleaning in the second processing step of FIG. 5A (step S12-2). FIGS. 14A and 14B show a case where the present invention is applied to the second processing step of FIG. 4A. As shown in FIG. 14A, a chemical cleaning sponge 52 is provided between the first linear transporter 6 and the table 30A. As shown in FIG. 14B, the columnar sponge 52 is rotated about its own axis by a plurality of rollers 53 installed on the outer periphery of the sponge 52. As a result, the upper surface of the sponge 52 comes into sliding contact with the wafer. A liquid supply path 52 a is formed at the center of the sponge 52. A liquid supply unit 54 is disposed below the sponge 52. The liquid mixture of the chemical liquid and DIW is supplied to the liquid supply path 52a of the sponge 52 via the liquid supply section 54, and is supplied to the sliding contact surface between the sponge 52 and the wafer from the upper opening of the liquid supply path 52a. Thus, the slurry abrasive grains can be removed by the physical removal action by the sponge 52 and the flowing water cleaning with the liquid supplied from the center of the sponge, and the carry-in to the subsequent stage of the slurry abrasive grains can be reduced. The sponge 52 may be replaced with a polishing cloth.

  FIG.14 (c) is a perspective view which shows the aspect provided with the sponge 52 for chemical | medical solution washing | cleaning on a table. As shown in FIG. 14 (c), a sponge 52 for cleaning chemicals is provided on the table 30A. The configuration of the sponge 52 shown in FIG. 14C is the same as that shown in FIG. Even when the sponge 52 is installed on the table, it is possible to remove slurry abrasive grains by physical removal action by the sponge and washing with flowing water supplied from the center of the sponge, and to reduce carry-on to the subsequent stage of the slurry abrasive grains. it can.

FIGS. 15A, 15 </ b> B, and 15 </ b> C are schematic diagrams illustrating an example of a configuration for performing chemical treatment of a wafer in the temporary placement table 180. The configurations shown in FIGS. 15A, 15B, and 15C are applied to the pre-cleaning chemical solution cleaning step.
FIG. 15A is a front view showing an aspect of a processing unit having a tilt mechanism installed outside the table. As shown in FIG. 15A, the processing unit includes a stage 61 on which the wafer W is placed, and the stage 61 can be tilted by a tilt mechanism. A chemical solution or DIW is supplied from the liquid supply unit 62 to the upper end portion side of the tilted stage 61. A stopper or the like for preventing the wafer from sliding down is provided on the lower end side of the tilted stage 61. The wafer W is processed in the following procedure. After the wafer W is placed on the stage 61, the stage 61 is tilted, and a chemical solution, DIW, or the like is supplied to the tilted upper end portion of the stage 61 to perform a chemical cleaning process on the wafer. After the processing, the stage 61 is returned to the horizontal level. Thus, the liquid on the wafer can be effectively discharged by tilting the wafer. It becomes possible to reduce the amount of the liquid which stays by improving the discharge property of the liquid.

FIG. 15B is a front view showing an aspect of a processing unit having a rotation mechanism (roller type). As shown in FIG. 15B, the peripheral edge of the wafer W is supported by a plurality of roller-type rotation mechanisms 65. Each roller type rotation mechanism 65 is supported by a spindle 66. The wafer W can be rotated about its own axis in a horizontal posture by rotation of each roller-type rotation mechanism 65. Above the wafer W, a liquid supply unit 68 having a plurality of nozzles 67 is disposed. The wafer W is processed in the following procedure. The outer peripheral edge of the wafer W is supported by a plurality of roller-shaped rotation mechanisms 65 to rotate the wafer W, and a liquid such as a chemical solution or DIW is flowed from the plurality of nozzles 67 onto the wafer W to process the wafer.
Thus, the liquid on the wafer can be effectively discharged by the roller-type rotation mechanism 65. It becomes possible to reduce the amount of the liquid which stays by improving the discharge property of the liquid. By adopting a roller type for the rotation mechanism 65, it is possible to wash away to the outer periphery of the wafer.

FIG. 15C is a front view illustrating an aspect of a processing unit having a rotation mechanism (chuck type). As shown in FIG. 15C, the peripheral portion of the wafer W is supported by a plurality of chucks 70. Each chuck 70 is supported by a rotatable stage 71. The wafer W is held by the chuck 70 and can rotate about its own axis in a horizontal posture by the rotation of the stage 71. The chuck 70 and the stage 71 constitute a chuck type rotation mechanism. Above the wafer W, a liquid supply unit 73 having a plurality of nozzles 72 is disposed. The wafer W is processed in the following procedure. The outer peripheral edge of the wafer W is supported by a plurality of chuck-type rotation mechanisms to rotate the wafer W, and a liquid such as a chemical solution or DIW is flowed from the plurality of nozzles 72 onto the wafer W to process the wafer.
By adopting the chuck-type rotation mechanism in this way, the wafer rotation speed (rotation speed) can be made wider than the roller-type rotation mechanism, and the process margin can be widened. It works.

FIGS. 16A, 16 </ b> B, and 16 </ b> C are schematic diagrams illustrating another example of a configuration for performing chemical treatment on a wafer in the temporary placement table 180. The configuration shown in FIGS. 16A, 16B, and 16C is applied to the pre-cleaning chemical solution cleaning step.
FIG. 16A is a front view showing an aspect of a processing unit having a tilt mechanism for tilting the rotation mechanism in addition to the rotation mechanism (chuck type). As shown in FIG. 16A, the peripheral edge of the wafer W is supported by a plurality of chucks 70. Each chuck 70 is supported by a rotatable stage 71. The stage 71 can be tilted by a tilt mechanism. The wafer W is held by the chuck 70 and is rotatable around its own axis in a posture inclined by the rotation of the stage 71. The chuck 70 and the stage 71 constitute a chuck type rotation mechanism. Above the wafer W, a liquid supply unit 73 having a plurality of nozzles 72 is disposed. The wafer W is processed in the following procedure. The outer periphery of the wafer W is held by a plurality of chucks 70 and the stage 71 is tilted. Then, the stage 71 is rotated to rotate the wafer W, and a liquid such as a chemical solution or DIW is flowed from the plurality of nozzles 72 onto the wafer W to process the wafer. Thus, by rotating the wafer by the chuck type rotation mechanism and tilting the wafer by the tilt mechanism, the liquid on the wafer can be effectively discharged. By further increasing the liquid discharge performance, it is possible to further reduce the amount of the liquid that stays.

  FIG. 16B is a front view showing a mode of a processing unit having a supply nozzle swinging mechanism in addition to the rotation mechanism (chuck type). As shown in FIG. 16B, the peripheral portion of the wafer W is supported by a plurality of chucks 70. Each chuck 70 is supported by a rotatable stage 71. The wafer W is held by the chuck 70 and can be rotated around its own axis by the rotation of the stage 71. Above the wafer W, a liquid supply unit 76 having a nozzle 75 that can be swung by a swinging mechanism is disposed. The wafer W is processed in the following procedure. The outer periphery of the wafer W is held by a plurality of chucks 70, the stage 71 is rotated to rotate the wafer W, and the nozzle 75 is swung by a rocking mechanism, and a liquid such as a chemical or DIW is transferred from the nozzle 75 onto the wafer W. To process the wafer W. In the case of a fixed nozzle, the position where it is sprayed from the nozzle and hits the wafer is fixed, but in the case of a swingable nozzle 75, the setting of the swing range and swing speed of the nozzle 75 can be adjusted in each process. It is possible to create a process margin.

  FIG. 16C is a front view showing an aspect of a processing unit having an immersion mechanism in addition to a chuck-type wafer holding mechanism and a tilt mechanism. As shown in FIG. 16C, the peripheral edge of the wafer W is supported by a plurality of chucks 70. Each chuck 70 is supported by a stage 78. The stage 78 has an immersion mechanism for immersing the wafer and can be tilted by a tilt mechanism. Above the wafer W, a liquid supply unit 80 having a plurality of nozzles 79 is disposed. The wafer W is processed in the following procedure. The outer peripheral edge of the wafer W is held by a plurality of chucks 70 and the stage 78 is tilted by a tilt mechanism. A liquid such as a chemical solution or DIW is supplied from a plurality of nozzles 79 to the immersion mechanism of the stage 78 to immerse the wafer in the liquid. In this way, the wafer is immersed in the liquid on the stage 78. By continuing to flow the liquid, the liquid can be prevented from staying, and after the treatment, the liquid can be discharged from the drain port 78p, and the clean chemical liquid and DIW can be continuously supplied.

FIGS. 17A, 17 </ b> B, and 17 </ b> C are schematic diagrams illustrating still another example of a configuration for performing chemical treatment on a wafer in the temporary placement table 180. The configuration shown in FIGS. 17A, 17B, and 17C is applied to the pre-cleaning chemical solution cleaning step.
FIG. 17A is a front view showing a mode of a processing unit having a swing mechanism of a two-fluid jet nozzle in addition to a rotating mechanism (roller type). As shown in FIG. 17A, the peripheral edge of the wafer W is supported by a plurality of roller-type rotation mechanisms 65. Each roller type rotation mechanism 65 is supported by a stage 82. The wafer W can be rotated around its own axis in a horizontal posture by the rotation of the stage 82. Above the wafer W, a liquid supply unit 84 having a two-fluid jet nozzle 83 that can be swung by a swing mechanism is installed. The wafer W is processed in the following procedure. The wafer W is rotated by supporting the outer peripheral edge of the wafer W by a plurality of roller-type rotating mechanisms 65, and a liquid such as a chemical solution or DIW is supplied onto the wafer W from the two-fluid jet nozzle 83 to process the wafer. At this time, the two-fluid jet nozzle 83 is swung to remove as much slurry as possible before going to the next-stage cleaning module. Thereby, the cleaning load of the cleaning module can be reduced.

  FIG. 17B is a front view showing an aspect of the processing unit having a slit nozzle that can be swung in addition to the rotation mechanism (chuck type). As shown in FIG. 17B, the peripheral portion of the wafer W is supported by a plurality of chucks 70. Each chuck 70 is supported by a rotatable stage 71. The wafer W is held by the chuck 70 and can rotate about its own axis in a horizontal posture by the rotation of the stage 71. Above the wafer W, a liquid supply part 86 having a swingable slit nozzle 85 is disposed. The wafer W is processed in the following procedure. The wafer W is rotated by holding the outer peripheral edge of the wafer W by a plurality of chucks 70, and a liquid such as a chemical solution or DIW is flowed onto the wafer W from a swingable slit nozzle 85 to process the wafer. The entire surface of the wafer can be rinsed by swinging the slit nozzle 85. Since the entire wafer surface can be wetted, the slurry discharging effect is improved. When the slit nozzle is not swung, the length of the slit nozzle may be set to a length corresponding to the radius of the wafer. Further, when the wafer is not rotated, the length of the slit nozzle may be set to the length corresponding to the diameter of the wafer.

FIG. 17C is a front view showing a mode of a processing unit having a scrub cleaning sponge in addition to the rotation mechanism (roller type). As shown in FIG. 17C, the peripheral edge of the wafer W is supported by a plurality of roller-type rotation mechanisms 65. Each roller-type rotation mechanism 65 is supported by the stage 71. The wafer W can be rotated around its own axis in a horizontal posture by the rotation of the stage 71. A disc-shaped sponge 87 for scrub cleaning is disposed above the wafer W. The wafer W is processed in the following procedure. The outer periphery of the wafer W is supported by a plurality of roller-type rotating mechanisms 65, the wafer W is rotated, and a liquid such as a chemical solution or DIW is supplied onto the wafer W through the inside of a scrub cleaning sponge 87 to scrub the wafer. Wash. By scrub cleaning with a sponge in this way, the slurry can be removed as much as possible before going to the cleaning module. Thereby, the cleaning load of the cleaning module can be reduced.
15 (a), (b), (c) to FIGS. 17 (a), (b), (c) in the form of each processing unit (except for the form of FIG. 16 (c)), the wafer 15 (a), (b), (c) to FIG. 17 (a), and FIG. 17 (a), are performed by performing face-down processing on the wafer. The mode of each processing unit shown in (b) and (c) (excluding the mode of FIG. 16 (c)) can be implemented at the top ring mechanism. In other words, the wafer may be held by the top ring so as to face down, and a nozzle or a scrub cleaning sponge may be disposed below the top ring.

  Although the embodiment of the present invention has been described so far, the present invention is not limited to the above-described embodiment, and it is needless to say that the present invention may be implemented in various different forms within the scope of the technical idea.

DESCRIPTION OF SYMBOLS 1 Housing 1a, 1b Bulkhead 2 Load / unload part 3 Polishing part 3A 1st grinding | polishing unit 3B 2nd grinding | polishing unit 3C 3rd grinding | polishing unit 3D 4th grinding | polishing unit 4 Cleaning part 5 Control part 6 1st linear transporter 7 2nd Linear transporter 10 Polishing pad 11 Lifter 12 Swing transporter 13 Table fixing ring 14 Ring-shaped guide 14a Inclined surface 15 Chemical solution supply nozzle 16, 17 Guide 16a Inclined surface 18 Base 19 Dip tank 19-1 First Dip tank 19-2 Second Dip Tank 19-3 Third Dip tank 20 Front load section 21 Travel mechanism 22 Transport robot 23 Chemical solution discharge nozzles 30A, 30B, 30C, 30D Polishing tables 31A, 31B, 31C, 31D Top ring 32 Top ring bodies 32A, 32B, 32C, 32D Polishing liquid supply Nozzle 32P Discharge port 33 Retainer ring 33A, 33B, 33C, 33D Dresser 33g Retainer ring groove 34 Membrane 34A, 34B, 34C, 34D Atomizer 35 Pressure chamber 36 Top ring shaft 41 Casket-shaped treatment tank 42 Supply pipe 43 Bowl-shaped process Tank 43g Guide 44 Supply pipe 45 Nozzle 46 Supply pipe 47 Cleaning nozzle 48 Main body 48h Nozzle hole 49 Cleaning nozzle 50 Main body 51 Cleaning nozzle 52 Sponge 52a Liquid supply path 53 Roller 54 Liquid supply section 60 Top ring head 61 Stage 65 Roller type Rotating mechanism 66 Spindle 67 Nozzle 68 Liquid supply unit 70 Chuck 71 Stage 72 Nozzle 73 Liquid supply unit 75 Nozzle 76 Liquid supply unit 78 Stage 78p Drain port 80 Liquid supply unit 82 Stage 83 Two fluid dice Liquid nozzle 87 Liquid supply unit 87 Sponge 180 Temporary table 190 First cleaning chamber 191 First transfer chamber 192 Second cleaning chamber 193 Second transfer chamber 194 Drying chamber 201A Upper primary cleaning module 201B Lower primary cleaning module 202A Upper Secondary cleaning module 202B Lower secondary cleaning module 203 Temporary table 205A Upper drying module 205B Lower drying module 209 First transport robot 210 Second transport robot 211, 212 Support shaft TP1 First transport position TP2 Second transport position TP3 Third transport position TP4 Fourth transport position TP5 Fifth transport position TP6 Sixth transport position TP7 Seventh transport position

Claims (7)

In a polishing apparatus that holds a substrate to be polished by a top ring and polishes the substrate by pressing the substrate against a polishing surface on a table,
A plurality of tables for performing a multi-stage polishing process on the substrate,
A polishing apparatus, wherein at least one of the plurality of tables is a chemical solution cleaning process dedicated table for performing a substrate cleaning process using a chemical solution. 2. The polishing apparatus according to claim 1 , wherein the chemical solution cleaning-dedicated table performs a substrate cleaning process using a chemical solution during the plurality of stages of polishing processes. The substrate is held by the top ring, the polishing apparatus according to claim 1 or 2, characterized in that to perform the chemical cleaning process of the substrate on the chemical liquid cleaning process only table. The chemical cleaning process dedicated table has at least one recess or tank for holding a chemical liquid, and performs a chemical cleaning process by immersing the substrate held by the top ring in the chemical liquid held in the recess or the tank. The polishing apparatus according to claim 3 , wherein the polishing apparatus is characterized. There are a plurality of tanks on the chemical cleaning process dedicated table,
The polishing apparatus according to claim 4 , wherein the plurality of tanks can hold different chemical solutions, or can hold at least one type of chemical solution and DIW, respectively. The chemical cleaning process only table, by repeating the stop and the rotation, according to claim, characterized in that the substrate held by the top ring can be immersed successively in the chemical or DIW in the plurality of the tank 5 The polishing apparatus according to 1. The top ring has a top ring main body having a membrane for holding the substrate, and a retainer ring fixed to the top ring main body and disposed so as to surround the outer peripheral edge of the substrate,
The retainer ring has grooves on the lower surface of the retainer ring that are spaced apart from each other to allow the chemical solution to flow into the lower surface of the substrate.
The top ring body has a port for discharging the chemical liquid flowing into the lower surface of the substrate,
Groove provided on the lower surface of the retainer ring according to claim 1, characterized in that the number of grooves in the portion far from the port is set to be larger than the number of the grooves of the portion close to the port The polishing apparatus as described in any one of thru | or 6 .

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