Substrate processing method and substrate processing apparatus

Abstract

To provide a substrate processing method that can shorten a drying step while avoiding problems caused by a member coming into contact with the outer periphery of a substrate during liquid processing, thereby contributing to improved productivity.SOLUTION: A hybrid chuck 10 includes a central chuck 20 that holds a substrate W at the center of its underside, and a peripheral chuck 30 that includes a plurality of gripping members 32 having side abutment portions 33 that abut against the side surfaces of the outer periphery of the substrate W. In a liquid processing step, a processing liquid is supplied to the surface of the substrate W while the central chuck 20 holds the substrate W horizontally. In a drying step, the substrate W is held horizontally by the central chuck 20 and gripped at its outer periphery by the peripheral chuck 30, and the liquid on the surface of the substrate W is shaken off by rotating the substrate W around a rotation axis A that runs vertically.SELECTED DRAWING: Figure 7D

Description

[Technical Field]

[0001] The present invention relates to a substrate processing method and a substrate processing apparatus for processing substrates, examples of which include semiconductor wafers, substrates for FPDs (Flat Panel Displays) such as liquid crystal displays and organic EL (Electroluminescence) displays, substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks, substrates for photomasks, ceramic substrates, and substrates for solar cells. [Background technology]

[0002] A single-wafer substrate processing apparatus is known that processes a substrate held horizontally by a spin chuck by supplying a processing liquid to the substrate. A substrate processing method in such a substrate processing apparatus typically includes a liquid processing step in which a processing liquid is supplied to the substrate held by the spin chuck, and a subsequent drying step in which the substrate is rotated by the rotation of the spin chuck to shake off the liquid.

[0003] One type of spin chuck grips a substrate with a plurality of chuck pins that contact the outer periphery of the substrate, and is called a mechanical chuck, as disclosed in Patent Document 1. Another type of spin chuck holds the substrate at the center of its underside, and includes the Bernoulli chuck shown in Patent Document 2 as well as a vacuum chuck that attracts the center of the underside of the substrate. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2021-100067 [Patent Document 2] Japanese Patent Application Publication No. 2023-45548 Summary of the Invention [Problem to be solved by the invention]

[0005] Mechanical chucks hold substrates by contacting chuck pins with the outer peripheral side surfaces of the substrate. Therefore, when processing liquid bounces off the chuck pins, it re-adheres to the substrate surface, resulting in particle generation. Furthermore, when etching liquid is used to remove a film from the surface of a substrate, a film may remain where the chuck pins are in contact, and this film may later peel off and adhere to the substrate surface, becoming contaminants. Furthermore, when the chuck pins block the etching liquid and flow to the underside of the substrate, the film on the underside may peel off and adhere to the substrate surface, becoming contaminants. Furthermore, during the drying process, the chuck pins are pressed firmly against the outer peripheral side surfaces in preparation for high-speed rotation of the substrate, which can cause chipping of the substrate or cracks in the film on the outer peripheral side surfaces, resulting in residue that adheres to the substrate surface and becomes contaminants or a source of contamination for subsequent processes. Thus, mechanical chucks face various challenges that arise at the outer peripheral portion of the substrate where the chuck pins are in contact.

[0006] Bernoulli chucks suck and hold substrates by ejecting gas from a fluid head facing the center of the substrate's underside, generating the Bernoulli effect. This eliminates the need for a component that abuts the substrate's periphery, thereby avoiding the problems associated with mechanical chucks. However, the substrate holding force achieved by the Bernoulli effect is less than that achieved by a mechanical chuck. Therefore, if a substrate is to be held by the Bernoulli effect alone, the upper limit of the substrate rotation speed during the drying process is limited to, for example, approximately 1500 rpm. This lengthens the drying process, lengthening substrate processing time and affecting productivity.

[0007] A vacuum chuck holds the substrate at the center of its underside using a vacuum, providing a stronger substrate holding force than a Bernoulli chuck. However, applying strong suction to the center of the substrate's underside can leave suction marks, which can contaminate the underside of the substrate. To avoid this, the suction force must be weakened, and the substrate rotation speed must be reduced accordingly, which increases the time required for the drying process.

[0008] Therefore, one embodiment of the present invention provides a substrate processing method that can shorten the drying step while avoiding problems caused by contact of a member with the outer periphery of the substrate during liquid processing, thereby contributing to improved productivity. Also, another embodiment of the present invention provides a substrate processing apparatus suitable for carrying out the above-mentioned substrate processing method. [Means for solving the problem]

[0009] An embodiment of the present invention provides a substrate processing apparatus and a substrate processing method having the following exemplary features.

[0010] 1. A liquid processing step in which a processing liquid is supplied to a surface (upper or lower surface) of the substrate while the substrate is held horizontally by a central chuck that holds the substrate at the center of the lower surface of the substrate; a drying process for shaking off liquid on the surface of the substrate by rotating the substrate about a rotation axis along a vertical direction while holding the substrate horizontally with the central chuck and gripping the substrate at its outer periphery with a peripheral chuck having a plurality of gripping members each having a side abutment portion that abuts against the side surface of the outer periphery of the substrate.

[0011] In this substrate processing method, the substrate is held by the central chuck during the liquid processing step, eliminating the need to hold the outer periphery of the substrate. This avoids problems caused by contacting a member with the outer periphery of the substrate during liquid processing. Meanwhile, the substrate is held by both the central chuck and the outer periphery chuck during the drying step. This allows the substrate to be rotated faster than when the substrate is held by the central chuck alone, shortening the drying process time. Furthermore, since the holding force of the central chuck can be weaker, problems caused by suction marks, for example, when the central portion of the substrate is strongly suction-held by a vacuum chuck, can be avoided. Furthermore, since the pressing force of the gripping member can be smaller than when the substrate is held by the outer periphery chuck alone, problems caused by strongly pressing the gripping member can be avoided.

[0012] 2. A substrate processing method as described in item 1, wherein the side contact portion of the gripping member is retracted from the outer peripheral side surface of the substrate during the liquid processing step, and is contacted with the outer peripheral side surface of the substrate during the drying step.

[0013] With this method, in the liquid processing step, the side contact portion of the gripping member is retracted from the outer peripheral side surface of the substrate, so that the outer peripheral side surface of the substrate is not in contact with any member along the entire periphery, thereby avoiding various problems caused by members in contact with the outer peripheral portion of the substrate during liquid processing.

[0014] 3. A centering step of centering the substrate by bringing the side contact portion of the gripping member into contact with the side surface of the outer periphery of the substrate, Item 3. The substrate processing method according to item 1 or 2, wherein, after the centering step, the side contact portion of the gripping member is retracted from the outer periphery of the substrate, and the side contact portion of the gripping member is placed in a non-contact state where it is not in contact with the substrate, and the liquid processing step is performed.

[0015] This method utilizes the gripping members of the outer periphery chuck to perform centering, i.e., aligning the center of the substrate with the rotation axis, and then allows the liquid processing step to be performed while the substrate is held at the center of its underside by the central chuck. Therefore, even when the substrate is rotated during the liquid processing step, the substrate can be stably held by the central chuck.

[0016] 4. A substrate processing method according to any one of items 1 to 3, wherein in the drying step, the substrate is rotated around the rotation axis at a predetermined drying rotation speed, and the side contact portion of the gripping member is pressed against the outer peripheral side of the substrate with a pressing force that is smaller than the expected pressing force required when the substrate is held by the outer peripheral chuck instead of the central chuck and rotated at the drying rotation speed.

[0017] As described above, in the drying process, the substrate is held by both the central chuck and the peripheral chuck, so the pressing force of the gripping members against the side surface of the peripheral portion of the substrate can be weak. Therefore, by reducing the pressing force of the gripping members, issues such as chipping of the peripheral portion of the substrate can be overcome.

[0018] 5. A substrate processing method according to any one of items 1 to 4, further comprising a lifting and lowering step of moving a lower surface support part up and down relative to the central chuck while supporting the substrate from below with the lower surface support part abutting the lower surface of the outer periphery of the substrate.

[0019] In this manner, the substrate can be moved up and down relative to the central chuck by raising and lowering the lower support, which facilitates loading and unloading of the substrate by a substrate transport robot.

[0020] 6. The substrate processing method according to item 5, wherein the gripping member has the lower surface support portion.

[0021] This method allows the substrate to be moved up and down relative to the central chuck by raising and lowering the gripping member without providing a dedicated lower surface support portion. This makes it easy for a substrate transport robot to load and unload the substrate. The substrate may be transferred between the peripheral chuck and the central chuck by raising and lowering the gripping member.

[0022] 7. The substrate processing method according to any one of items 1 to 6, wherein the central chuck includes a Bernoulli chuck.

[0023] Although the Bernoulli chuck does not have a substrate holding force large enough to withstand high-speed rotation, it is suitable for holding a substrate during liquid processing that does not require high-speed rotation, and has the advantage of being able to hold the substrate with the outer peripheral side surface of the substrate open. On the other hand, in the drying process, the substrate is also held by the outer peripheral chuck, so the drying process time can be shortened by rotating the substrate at high speed. In addition, the contribution of the Bernoulli chuck to substrate holding reduces the pressing force of the outer peripheral chuck's gripping member against the outer peripheral side surface of the substrate, thereby preventing damage to the outer peripheral portion of the substrate.

[0024] 8. The substrate processing method according to any one of items 1 to 6, wherein the central chuck includes a vacuum chuck.

[0025] The vacuum chuck can hold the substrate while leaving the outer peripheral side of the substrate open, allowing the entire outer peripheral side of the substrate to be processed thoroughly during the liquid processing process. Meanwhile, during the drying process, the substrate is also held by the outer peripheral chuck, eliminating the need for the vacuum chuck to strongly suction the central portion of the substrate's underside. This allows the substrate to be rotated at high speed while minimizing the occurrence of suction marks, thereby shortening the drying process time. Additionally, the vacuum chuck's contribution to substrate holding reduces the pressing force of the outer peripheral chuck's gripping members against the outer peripheral side of the substrate, preventing damage to the outer peripheral portion of the substrate.

[0026] 9. A hybrid chuck in which a central chuck for holding a substrate at the center of the lower surface of the substrate and a peripheral chuck having a plurality of gripping members for contacting the peripheral side surface of the substrate are arranged to share a predetermined rotation axis along the vertical direction; a lifting mechanism that moves the gripping member up and down relative to the central chuck; an opening / closing mechanism that displaces the gripping member between a closed state in which the gripping member abuts against a side surface of an outer periphery of the substrate and an open state in which the gripping member is retracted from the side surface of the outer periphery of the substrate.

[0027] This configuration makes it possible to provide a substrate processing apparatus suitable for carrying out the above-described substrate processing method.

[0028] 10. The substrate processing apparatus according to item 9, wherein the gripping member has a side contact portion that contacts the side surface of the outer periphery of the substrate, and a lower surface support portion that contacts the lower surface of the outer periphery of the substrate.

[0029] 11. Further comprising a controller for controlling the lifting mechanism and the opening / closing mechanism; The controller Item 11. The substrate processing apparatus according to item 10, wherein the gripping member is moved up and down relative to the central chuck in a state where the substrate is supported from below by the lower surface support portion.

[0030] 12. The controller further controls the central chuck; Item 12. The substrate processing apparatus according to item 11, wherein the controller abuts the side contact portion of the gripping member against the outer peripheral side surface of the substrate to center the substrate (align the center of the substrate with the rotation axis), then retracts the side contact portion from the outer peripheral side surface of the substrate, and then holds the substrate with the central chuck.

[0031] 13. A processing liquid nozzle for supplying a processing liquid to the substrate held by the hybrid chuck; a controller for controlling the central chuck and the peripheral chuck; The controller In a liquid processing step in which a processing liquid is supplied from the processing liquid nozzle to the substrate held by the hybrid chuck, the central chuck is controlled to a holding state in which the substrate is held, and the outer peripheral chuck is controlled to a non-holding state in which the central chuck is not in contact with the substrate, Item 13. The substrate processing apparatus according to any one of items 9 to 12, wherein in a drying step of stopping the supply of the processing liquid from the processing liquid nozzle and rotating the substrate around the rotation axis at a predetermined drying rotation speed to dry the substrate, both the central chuck and the outer periphery chuck are controlled to a holding state in which they hold the substrate.

[0032] 14. A substrate processing apparatus as described in item 13, wherein the controller controls the opening and closing mechanism so that, during the drying process, the substrate is rotated around the rotation axis at the drying rotation speed, and the gripping member is pressed against the outer peripheral side of the substrate with a pressing force that is smaller than the expected pressing force required when the substrate is held by the outer periphery chuck rather than the central chuck and rotated at the drying rotation speed.

[0033] 15. The substrate processing apparatus according to item 14, wherein the opening and closing mechanism is capable of varying (preferably continuously varying) the pressing force of the gripping member against the outer peripheral side surface of the substrate.

[0034] 16. The substrate processing apparatus according to any one of items 9 to 15, wherein the central chuck includes a Bernoulli chuck.

[0035] 17. The substrate processing apparatus according to any one of items 9 to 15, wherein the central chuck includes a vacuum chuck. [Brief explanation of the drawings]

[0036] [Figure 1] FIG. 1 is a schematic plan view showing the layout of a substrate processing system including a substrate processing apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a side view showing an example of the configuration of a processing unit (an example of a substrate processing apparatus), and a vertical cross section of part of the configuration is shown. [Figure 3] FIG. 3 is a block diagram for explaining the electrical configuration of the substrate processing apparatus. [Figure 4A] FIG. 4A is a vertical cross-sectional view showing an example of the configuration of a hybrid chuck. [Figure 4B] FIG. 4B is a plan view showing an example of the configuration of a hybrid chuck. [Figure 5A] FIG. 5A is a schematic cross-sectional view for explaining an example of the configuration of a periphery chuck. [Figure 5B] FIG. 5B is a schematic cross-sectional view for explaining an example of the configuration of the outer periphery chuck. [Figure 5C] FIG. 5C is a schematic cross-sectional view for explaining an example of the configuration of the outer periphery chuck. [Figure 6] FIG. 6 is a flowchart illustrating an example of substrate processing. [Figure 7A] FIG. 7A is a schematic cross-sectional view showing the state of the hybrid chuck in a main process. [Figure 7B] FIG. 7B is a schematic cross-sectional view showing the state of the hybrid chuck in a main process. [Figure 7C] FIG. 7C is a schematic cross-sectional view showing the state of the hybrid chuck in a main process. [Figure 7D] FIG. 7D is a schematic cross-sectional view showing the state of the hybrid chuck in a main process. [Figure 8A] FIG. 8A is a cross-sectional view for explaining another embodiment of the present invention, showing another example of the configuration of a hybrid chuck. [Figure 8B] FIG. 8B is a cross-sectional view for explaining another embodiment of the present invention, showing another configuration example of a hybrid chuck. [Figure 8C] FIG. 8C is a cross-sectional view for explaining another embodiment of the present invention, showing another example of the configuration of a hybrid chuck. [Figure 8D] FIG. 8D is a cross-sectional view for explaining another embodiment of the present invention, showing another example of the configuration of a hybrid chuck. [Figure 9A] FIG. 9A is a diagram for explaining still another embodiment of the present invention, showing another example of the configuration of the outer periphery chuck. [Figure 9B] FIG. 9B is a diagram for explaining still another embodiment of the present invention, showing another example of the configuration of the outer periphery chuck. DETAILED DESCRIPTION OF THE INVENTION

[0037] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0038] 1 is a schematic plan view showing the layout of a substrate processing system 100 including a substrate processing apparatus according to one embodiment of the present invention. The substrate processing system 100 is a system for processing substrates W such as semiconductor substrates. The substrate processing system 100 includes an indexer block 1 and a processing block 4 coupled to the indexer block 1.

[0039] The indexer block 1 comprises a carrier holding unit 2 and an indexer robot 3. The carrier holding unit 2 is configured to hold a plurality of carriers C, each capable of accommodating a plurality of substrates W. The plurality of carriers C (for example, FOUPs (Front Opening Unified Pods)) are held by the carrier holding unit 2 in an arrayed state in a predetermined carrier array direction (the vertical direction in FIG. 1). The indexer robot 3 is movable in the carrier array direction. The indexer robot 3 performs an unloading operation to unload a substrate W from a carrier C, and a loading operation to load a substrate W into a carrier C held by the carrier holding unit 2. The substrate W is transported by the indexer robot 3 in a horizontal position.

[0040] The processing block 4 includes a plurality of processing units 5 that process substrates W, and a center robot 6 (substrate transport robot). The processing units 5 are arranged to surround the center robot 6 in a plan view, and may be stacked vertically in multiple layers. The processing units 5 perform various processes on the substrates W. The processing units 5 are an example of a substrate processing apparatus. The center robot 6 performs a load operation to load the substrate W into the processing unit 5 and an unload operation to unload the substrate W from the processing unit 5. The center robot 6 can also transport the substrate W between the plurality of processing units 5. The substrate W is held horizontally by a hand 6a of the center robot 6 and transported in a horizontal position. The center robot 6 receives unprocessed substrates W from the indexer robot 3 and passes processed substrates W to the indexer robot 3.

[0041] FIG. 2 is a side view showing an example of the configuration of a processing unit 5 (an example of a substrate processing apparatus), with a longitudinal cross section of part of the configuration. The processing unit 5 is a single-wafer type substrate processing apparatus that processes substrates W one by one. The processing unit 5 performs liquid processing, in which a processing liquid is supplied to the substrate W, and drying processing, in which the liquid on the substrate W is shaken off after the liquid processing. The processing liquid may be a chemical liquid or a rinse liquid. The chemical liquid may be a cleaning liquid for cleaning the surface of the substrate W, or an etching liquid for an etching process. The rinse liquid is typically DIW (deionized water), but other types of liquids such as carbonated water and IPA (isopropyl alcohol) may also be used as the rinse liquid.

[0042] The processing unit 5 includes a hybrid chuck 10, a substrate rotation mechanism 11, a processing liquid nozzle 15, a nozzle movement mechanism 18, a lower surface nozzle 19, a processing cup 73, a controller 8, and a chamber 80.

[0043] The hybrid chuck 10 is a substrate holder that holds one substrate W in a horizontal position. The substrate rotation mechanism 11 rotates the substrate W around a vertical rotation axis A that passes through the center of the substrate W. More specifically, the substrate rotation mechanism 11 rotates the hybrid chuck 10 around the rotation axis A.

[0044] The processing liquid nozzle 15 supplies a processing liquid to the surface (upper surface) of the substrate W held and rotated by the hybrid chuck 10. The processing liquid is supplied to the processing liquid nozzle 15 through a processing liquid pipe 16. A processing liquid valve 17 is interposed in the processing liquid pipe 16. In this embodiment, the processing liquid nozzle 15 is a movable nozzle that can be moved by a nozzle moving mechanism 18. The nozzle moving mechanism 18 moves the processing liquid nozzle 15 between a processing position above the substrate W held by the hybrid chuck 10 and a retracted position where the processing liquid nozzle 15 is retracted laterally from above the substrate W.

[0045] The lower surface nozzle 19 has a discharge port 19a facing the center of the lower surface of the substrate W held by the hybrid chuck 10, and supplies a processing fluid (liquid or gas, for example, an inert gas such as nitrogen gas or dry air) toward the center of the lower surface of the substrate W. The lower surface nozzle 19 is disposed inside the shaft 12 of the substrate rotation mechanism 11. The processing fluid is supplied to the lower surface nozzle 19 via a processing fluid pipe 71. A processing fluid valve 72 is provided in the processing fluid pipe 71.

[0046] The processing cup 73 is disposed to surround the hybrid chuck 10 and captures the liquid discharged outward from the substrate W by centrifugal force. A drain port (not shown) is provided at the bottom of the processing cup 73 to discharge the captured liquid to the outside of the chamber 80.

[0047] The hybrid chuck 10, the substrate rotation mechanism 11, the processing cup 73, the processing liquid nozzle 15, etc. are housed in an internal space 82 of the chamber 80. An airflow forming unit 83 is provided in the canopy 81 of the chamber 80 to supply gas to the internal space 82 of the chamber 80 and form an airflow flowing downward (so-called downflow). As the airflow forming unit 83, for example, an FFU (fan filter unit) is used.

[0048] The hybrid chuck 10 and the substrate rotation mechanism 11 form a spin chuck that holds a substantially disk-shaped substrate W in a horizontal position and rotates it about a rotation axis A along the vertical direction. The substrate rotation mechanism 11 is disposed below the hybrid chuck 10. The substrate rotation mechanism 11 rotates the substrate W together with the hybrid chuck 10 about the rotation axis A. The substrate rotation mechanism 11 includes a shaft 12 and an electric motor 14. The shaft 12 is a substantially cylindrical member whose center is the rotation axis A. The shaft 12 extends in the vertical direction and is connected to the hybrid chuck 10. The electric motor 14 rotates the shaft 12. The electric motor 14 may be a hollow motor.

[0049] The controller 8 is disposed outside the chamber 80. The controller 8 is, for example, a computer system including a processor 8p and a memory 8m. The processor 8p executes various processes in accordance with programs stored in the memory 8m. As a result, the controller 8 controls the operations of the control targets, such as the indexer robot 3, the center robot 6, the hybrid chuck 10, the substrate rotation mechanism 11, the nozzle movement mechanism 18, and the valves 17 and 72.

[0050] Fig. 4A is a vertical cross-sectional view showing an example of the configuration of the hybrid chuck 10, and Fig. 4B is a plan view of the hybrid chuck 10. In Fig. 4B, the substrate W held by the hybrid chuck 10 is indicated by a two-dot chain line.

[0051] The hybrid chuck 10 is configured by combining and integrating a central chuck 20, which holds the substrate W in a horizontal position at the center of the lower surface of the substrate W, and a peripheral chuck 30, which has a plurality of gripping members 32 that abut against the side surfaces of the outer periphery of the substrate W, so that they share a rotation axis A. Either the central chuck 20 or the peripheral chuck 30 can hold the substrate W in a horizontal position, or both of them can hold the substrate W in a horizontal position.

[0052] The peripheral chuck 30 includes a disk-shaped base 31 (hereinafter referred to as the "periphery base 31") and a plurality of gripping members 32 protruding upward from the peripheral edge of the peripheral base 31. In this example, six gripping members 32 are arranged at equal intervals on a circle around the rotation axis A. The outer edge of the peripheral base 31 is located radially outward (radially from the rotation axis A) from the outer peripheral edge of the substrate W, and the gripping members 32 are arranged radially outward from the outer peripheral edge of the substrate W.

[0053] Each gripping member 32 is composed of a gripping pin extending in the vertical direction, and has at its upper end a side abutment portion 33 that abuts against the side surface of the outer periphery of the substrate W, and a lower surface support portion 34 that abuts against the lower surface of the outer periphery of the substrate W. The side abutment portion 33 faces the side surface of the outer periphery of the substrate W, and the lower surface support portion 34 faces the lower surface of the outer periphery of the substrate W. The gripping members 32 are configured to be displaceable between a closed state in which the side abutment portion 33 abuts against the side surface of the outer periphery of the substrate W, and an open state in which the side abutment portion 33 is retracted from the side surface of the outer periphery of the substrate W. More specifically, as the gripping members 32 rotate about a rotation axis 36 extending in the vertical direction, the distance between the side abutment portion 33 and the rotation axis A changes, and accordingly the distance between the side abutment portion 33 and the side surface of the outer periphery of the substrate W changes.

[0054] Furthermore, in this example, the gripping member 32 is configured to be movable up and down in the vertical direction relative to the outer periphery base 31, thereby mediating the transfer of the substrate W between the center robot 6 and the hybrid chuck 10, and is configured to be able to transfer the substrate W between the outer periphery chuck 30 (more specifically, the lower surface support portion 34 of the gripping member 32) and the central chuck 20.

[0055] A central chuck 20 is incorporated into the central portion of the outer peripheral base 31. In this example, the central chuck 20 is a Bernoulli chuck that adsorbs and holds the substrate W by the Bernoulli effect. The central chuck 20 comprises a base 21 (hereinafter referred to as the "central base 21") incorporated into the central portion of the outer peripheral base 31, and a gas supply unit 22. The central base 21 is a substantially disk-shaped member centered on the rotation axis A. The central base 21 has an upper surface (adsorption surface) that faces the lower surface of the substrate W. The upper surface of the central base 21 is a substantially horizontal plane. The diameter of the central base 21 is smaller than the diameter of the substrate W, and the outer edge of the upper surface of the central base 21 is located radially inward from the outer periphery of the substrate W.

[0056] The gas supply unit 22 includes a gas discharge port 23 that opens on the upper surface of the central base 21 and a gas flow path 24 that supplies gas to the gas discharge port 23. In this embodiment, the gas discharge port 23 is an annular slit opening centered on the rotation axis A. Instead of such a single annular slit opening, the gas discharge port 23 may be a plurality of discrete openings arranged in an annular shape. The gas discharge port 23 is connected to a gas supply source 25 via the gas flow path 24 provided inside the central base 21.

[0057] The outer periphery base 31 and the central base 21 are coupled to the shaft 12 of the substrate rotation mechanism 11. The shaft 12 is a hollow shaft having a through-hole 13 penetrating in the axial direction. A bottom nozzle 19 passes through the through-hole 13. A gas supply path 26 is formed between the bottom nozzle 19 and the inner peripheral surface of the through-hole 13, and this gas supply path 26 communicates with the gas flow path 24. The gas supply path 26 has a gas discharge port 26a opening at the center of the upper surface of the central base 21, and gas can be discharged from the gas discharge port 26a toward the center of the lower surface of the substrate W. Gas can be supplied to the gas supply path 26 from a gas supply source 25 via a gas pipe 27. This gas may be, for example, an inert gas such as nitrogen gas, or air. This gas may be, for example, a high-pressure gas or a compressed gas. When gas valve 28 provided on gas pipe 27 is opened, gas supplied from gas supply source 25 passes through gas supply path 26 and gas flow path 24, is discharged from gas discharge port 23, and is also discharged from gas discharge port 26a at the center of central base 21.

[0058] The gas flow passage 24 extends obliquely radially outward and upward near the gas discharge port 23. The gas discharge port 23 is disposed inward from the outer periphery of the substrate W and opens below the substrate W. Therefore, gas is discharged from the gas discharge port 23 radially outward and upward toward the underside of the substrate W. This gas flows radially outward almost horizontally along the underside of the substrate W. In addition, gas discharged from the central gas discharge port 26a of the central base 21 also flows radially outward along the underside of the substrate W. As a result, an airflow is formed in the space below the substrate W, directed from the radial center toward the radially outward direction. This airflow causes a pressure drop in the space below the substrate W due to the Bernoulli effect. As a result, the central portion of the substrate W is attracted to the central chuck 20.

[0059] As the flow rate of the gas delivered from the gas discharge ports 23, 26a increases, the downward suction force acting on the substrate W correspondingly increases. When the gas discharge stops, the suction force disappears.

[0060] 5A, 5B, and 5C are schematic cross-sectional views illustrating an example configuration of the periphery chuck 30. The periphery base 31 includes a base plate 41 fixed to the shaft 12 and a base cover 42 connected to the base plate 41. The base plate 41 is housed within the base cover 42. A gripping member 32 is connected to the base plate 41 via a bearing 44. The gripping member 32 has a shaft portion 35 that penetrates the base plate 41 in the vertical direction and further penetrates the top surface portion 43 of the base cover 42 and protrudes upward. A lower surface support portion 34 and a side surface abutment portion 33 are provided at the upper end of the shaft portion 35. The bearing 44 connects the shaft portion 35 of the gripping member 32 to the base plate 41 so as to rotate about the rotation axis 36 and guide the vertical movement relative to the base plate 41. The side surface abutment portion 33 is provided at a position eccentric to the rotation axis 36. Therefore, the distance between the side surface abutment portion 33 and the outer peripheral side surface of the substrate W changes due to the rotation of the gripping member 32 around the rotation axis .

[0061] A gripping member drive mechanism 45 is provided for rotating the gripping member 32 about the rotation axis 36 and moving it up and down. The gripping member drive mechanism 45 includes a cam mechanism 46 and a cam drive mechanism 51 that applies a drive force to the cam mechanism 46.

[0062] The cam mechanism 46 includes a cam follower 47 fixed to the lower end of the shaft portion 35 of the gripping member 32, and a cam lever 49 coupled to the cam follower 47. A compression coil spring 55 is wound around the shaft portion 35 of the gripping member 32 between the cam follower 47 and the base plate 41, and urges the cam follower 47 and the gripping member 32 downward. The cam lever 49 is housed in the base cover 42 and is movable up and down below the base plate 41. The cam follower 47 has a cam groove 48 that is inclined relative to the vertical direction, and a drive end 50 of the cam lever 49 is coupled to this cam groove 48. A compression coil spring 56 that presses down the cam lever 49 is arranged between the cam lever 49 and the underside of the base plate 41.

[0063] The cam drive mechanism 51 is disposed in a non-rotating system outside the base cover 42. The cam drive mechanism 51 includes a ball screw mechanism 52, an electric motor 53 that provides driving force to the ball screw mechanism 52, and a drive rod 54 that is moved up and down by the ball screw mechanism 52. A ring-shaped lift plate 57 that surrounds the rotation axis A is connected to the upper end of the drive rod 54. A ring-shaped ball bearing 58 that surrounds the rotation axis A is disposed between the lift plate 57 and the cam lever 49. One raceway of the ball bearing 58 is connected to the lift plate 57, and the other raceway is connected to the cam lever 49.

[0064] When the cam drive mechanism 51 is driven, the lifting plate 57 moves up and down, and this up and down movement is transmitted to the cam lever 49 via the ball bearing 58, causing the cam lever 49 to also move up and down. As a result, the drive end 50 of the cam lever 49 moves within the cam groove 48 of the cam follower 47, displacing the cam follower 47 in the radial direction. This causes the gripping member 32 to rotate about the rotation axis 36. This causes the distance between the side surface abutment portion 33 and the rotation axis A, i.e., the distance between the side surface abutment portion 33 and the outer peripheral side surface of the substrate W, to vary.

[0065] In this embodiment, when the cam lever 49 is lowered and the cam follower 47 is displaced radially outward, the side surface abutment portion 33 is displaced in a direction approaching the rotation axis A and approaches the outer peripheral side surface of the substrate W. Therefore, as shown in FIG. 5A , by lowering the cam lever 49, the side surface abutment portion 33 can be brought into contact with the outer peripheral side surface of the substrate W and pressed against the outer peripheral side surface of the substrate W. In other words, the gripping member 32 can be placed in a closed state. The pressing force of the side surface abutment portion 33 against the outer peripheral side surface of the substrate W can be continuously varied by changing the driving force applied from the cam drive mechanism 51 including the ball screw mechanism 52, i.e., the torque generated by the electric motor 53.

[0066] When the cam drive mechanism 51 raises the lifting plate 57 to raise the cam lever 49, the cam follower 47 is displaced radially inward, as shown in Fig. 5B. This causes the side surface abutment portion 33 to be displaced in a direction away from the rotation axis A and away from the outer peripheral side surface of the substrate W. This allows the gripping member 32 to be in the open state.

[0067] When the cam lever 49 is further raised by the cam drive mechanism 51 after the drive end 50 of the cam lever 49 has reached the upper end of the cam groove 48, the cam follower 47 can be raised, as shown in FIG. 5C, thereby raising the gripping member 32 to the upper position. As a result, the lower surface of the outer periphery of the substrate W is supported by the lower surface support portion 34 of the gripping member 32, allowing the substrate W to be lifted. When the cam lever 49 is lowered from this state by the cam drive mechanism 51, the cam follower 47 is pressed down by the compression coil spring 55, thereby lowering the gripping member 32 to the lower position shown in FIG. 5B. In this way, the gripping member 32 moves up and down between the upper position (see FIG. 5C) and the lower position (see FIGS. 5A and 5B), thereby functioning as a lift pin that moves the substrate W in the vertical direction. The gripping member driving mechanism 45 is a lifting mechanism that moves the gripping member 32 up and down relative to the central chuck 20, and also serves as an opening and closing mechanism that moves the gripping member between a closed state and an open state. Of course, the lifting mechanism and the opening and closing mechanism may be provided separately.

[0068] The upper position of the gripping member 32 is a transfer position where the substrate W is transferred between the hand 6a (see FIG. 1) of the center robot 6 (substrate transport robot) and the hybrid chuck 10. The lower position of the gripping member 32 is a position where the substrate W can be held by the central chuck 20. Therefore, the lower position is a position where both the peripheral chuck 30 and the central chuck 20 can hold the substrate W, and thus a position where the substrate W can be transferred between the peripheral chuck 30 and the central chuck 20. When the gripping member 32 is in the lower position, the gripping member 32 is in the open state and the central chuck 20 can hold the substrate W alone (see FIG. 5B). Also, when the gripping member 32 is in the lower position, the gripping member 32 is in the closed state and the peripheral chuck 30 can hold (grasp) the substrate W. Therefore, as shown in FIG. 5A, the central chuck 20 can hold the substrate W at the center of the lower surface of the substrate W, and the peripheral chuck 30 can hold the substrate W at the peripheral portion of the substrate W.

[0069] Fig. 6 is a flowchart for explaining an example of substrate processing. Figs. 7A to 7D are schematic cross-sectional views showing the states of the hybrid chuck 10 in main steps. The operation of each step described below is achieved by the controller 8 controlling each part in accordance with a predetermined program and a substrate processing recipe.

[0070] The substrate W to be processed is carried into the processing unit 5 by the center robot 6 and transferred to the peripheral chuck 30 (step S1). The substrate W transferred to the gripping members 32 is supported in a horizontal position by the lower surface support portions 34 of the gripping members 32 abutting against the lower surface of the outer periphery of the substrate W. At this time, as shown in FIG. 7A, the gripping members 32 are placed in an open state and in an upper position under the control of the cam drive mechanism 51 by the controller 8. Also, gas discharge from the gas discharge ports 23, 26a is stopped, and therefore the central chuck 20 (Bernoulli chuck) is in an inactive state (non-adsorbing state, non-holding state).

[0071] Next, the controller 8 controls the cam drive mechanism 51 to lower the gripping members 32 to the lower position while the substrate W is supported by the lower surface support parts 34 (step S2). Furthermore, the cam drive mechanism 51 controls the gripping members 32 to close, and the side surface abutment parts 33 of the gripping members 32 abut against the outer peripheral side surfaces of the substrate W. This results in alignment of the center of the substrate W with the rotation axis A, i.e., centering (step S3; see FIG. 7B).

[0072] Next, the controller 8 opens the gas valve 28 to start discharging gas from the gas discharge port 23, thereby causing the central chuck 20 (Bernoulli chuck) to enter an operating state (suction state, holding state) (step S4; see FIG. 7C). Then, the cam drive mechanism 51 controls the gripping members 32 to enter an open state (non-holding state), and the holding by the peripheral chuck 30 is released. As a result, the substrate W is transferred from the peripheral chuck 30 to the central chuck 20, and the substrate W is held only by the central chuck 20. At this time, the gripping members 32 are not in contact with either the side or bottom surface of the outer periphery (bevel) of the substrate W, and the substrate W is held by the central chuck 20 in a bevel-free state. The Bernoulli chuck generates an airflow on the bottom surface of the substrate W to suck the substrate W, so that the substrate W is held by the central chuck 20 in a state where it is floating above the bottom support portions 34 of the gripping members 32. If necessary, the gripping members 32 may be slightly lowered to ensure a gap between the lower surface of the outer periphery of the substrate W and the lower surface support parts .

[0073] In this state, while the substrate W is held only by the central chuck 20, liquid processing is performed by supplying a processing liquid to the surface of the substrate W while rotating the substrate W (step S5, liquid processing step; see FIG. 7C). That is, the controller 8 controls the substrate rotation mechanism 11 to rotate the hybrid chuck 10 about the rotation axis A, thereby rotating the substrate W about the rotation axis A at a predetermined liquid processing rotation speed (e.g., 800 rpm). The liquid processing rotation speed is set to an appropriate value equal to or less than the upper limit rotation speed (e.g., 1500 rpm) at which the substrate W can be held and rotated by the central chuck 20 (Bernoulli chuck) alone. In addition, the controller 8 controls to open the processing liquid valve 17, thereby discharging the processing liquid from the processing liquid nozzle 15 toward the surface (here, the upper surface) of the substrate W. As shown in FIG. 7C, a processing fluid (processing liquid or processing gas) may be discharged from the lower surface nozzle 19 as needed. After the liquid processing is performed for a predetermined liquid processing time, the discharge of the processing liquid from the processing liquid nozzle 15 is stopped.

[0074] Next, at the start of the drying step in which the substrate W is rotated around the rotation axis A at a predetermined drying rotation speed (for example, 2500 rpm) to shake off the liquid, the controller 8 controls the cam drive mechanism 51 to control the gripping members 32 to a closed state (holding state). That is, the side abutment portions 33 of the gripping members 32 abut against the side surfaces of the outer periphery of the substrate W, and the outer periphery chuck 30 begins to hold the substrate. That is, the substrate W is held at the center of its lower surface by the central chuck 20, and at the outer periphery by the outer periphery chuck 30 (step S6; see FIG. 7D).

[0075] The controller 8 controls the cam drive mechanism 51 to perform pressing force control to adjust the pressing force (step S7). More specifically, the controller 8 controls the pressing force by controlling the torque generated by the electric motor 53. The pressing force is controlled to a value smaller than the assumed pressing force required when the substrate W is not held by the central chuck 20 but is held only by the peripheral chuck 30 and is rotated at the drying rotation speed. In other words, the torque generated by the electric motor 53 is controlled so that such pressing force is achieved.

[0076] While controlling the pressing force in this manner, the drying process is carried out (step S8). That is, the controller 8 controls the substrate rotation mechanism 11 to accelerate the rotation speed of the substrate W to the drying rotation speed and maintains the drying rotation speed for a predetermined drying time. Thereafter, the rotation of the substrate is stopped, and the drying process is completed. During the drying process, an inert gas may be ejected from the lower surface nozzle 19 to promote drying.

[0077] Next, the controller 8 closes the gas valve 28 and stops the gas discharge from the gas discharge port 23, thereby releasing the suction and holding by the central chuck 20 (Bernoulli chuck) (step S9). As a result, the substrate W is held only by the peripheral chuck 30, and the substrate W is transferred from the central chuck 20 to the peripheral chuck 30.

[0078] Thereafter, the controller 8 controls the cam drive mechanism 51 to open the gripping members 32, move the side abutment portions 33 away from the outer peripheral side surfaces of the substrate W, and further raise the gripping members 32 to the raised position while the lower surface support portions 34 support the lower surface of the outer peripheral portion of the substrate W (step S10; see FIG. 7A). Thereafter, the center robot 6 scoops up the processed substrate W from the open gripping members 32 and carries it out (step S11). In this way, the processing of one substrate W is completed.

[0079] As described above, in this embodiment, since the substrate W is held by the central chuck 20 in the liquid treatment step, there is no need to hold the outer periphery of the substrate W. Therefore, problems caused by a member abutting the outer periphery of the substrate W during liquid treatment can be avoided. On the other hand, in the drying step, the substrate W is held by both the central chuck 20 and the outer periphery chuck 30. Therefore, the substrate W can be rotated at a higher speed than when the substrate W is held by the central chuck 20 alone, thereby shortening the drying treatment time. In addition, since the pressing force of the gripping member 32 can be made smaller than when the substrate W is held by the outer periphery chuck 30 alone, problems caused by pressing the gripping member 32 too hard can be avoided.

[0080] In this embodiment, the side surface contact portions 33 of the gripping members 32 are retracted from the outer peripheral side surface of the substrate W during the liquid processing step, and are brought into contact with the outer peripheral side surface of the substrate during the drying step. Therefore, during the liquid processing step, the outer peripheral side surface of the substrate W is not in contact with any member along the entire periphery. This makes it possible to avoid various problems caused by members contacting the outer peripheral portion of the substrate W during liquid processing.

[0081] Furthermore, in this embodiment, a centering step is performed in which the side contact portions 33 of the gripping members 32 are brought into contact with the side surfaces of the outer periphery of the substrate W to center the substrate W. After the centering step, the side contact portions 33 of the gripping members 32 are retracted from the outer periphery of the substrate W, and the side contact portions 33 are placed in a non-contact state where they do not contact the substrate W, and then the liquid processing step is performed. That is, centering, i.e., an alignment operation for aligning the center of the substrate with the rotation axis A, is performed using the gripping members 32 of the outer periphery chuck 30, and then the liquid processing step can be performed while the central chuck 20 holds the substrate W at the center of its lower surface. Therefore, when the substrate W is rotated in the liquid processing step, the substrate W can be stably held by the central chuck 20.

[0082] Furthermore, in this embodiment, when the substrate W is rotated around the rotation axis A at a predetermined drying rotation speed in the drying process, the side contact portions 33 of the gripping members 32 are pressed against the side surfaces of the outer periphery of the substrate W with a pressing force that is smaller than the assumed pressing force required when the substrate W is held by the outer periphery chuck 30 instead of the central chuck 20 and rotated at the drying rotation speed. In the drying process, the substrate is held by both the central chuck 20 and the outer periphery chuck 30, so the pressing force of the gripping members 32 against the side surfaces of the outer periphery of the substrate W may be weak. Therefore, by reducing the pressing force of the gripping members, problems such as chipping on the outer periphery of the substrate W can be overcome.

[0083] In this embodiment, the substrate W is supported from below by the lower surface support parts 34 that contact the lower surface of the outer periphery of the substrate W, and the lower surface support parts 34 are moved up and down relative to the central chuck 20 (lifting and lowering process). This makes it easier for the center robot 6 (substrate transport robot) to load and unload the substrate W.

[0084] In this embodiment, the gripping member 32 has a lower surface support portion 34. Therefore, the substrate W can be moved up and down relative to the central chuck 20 by raising and lowering the gripping member 32 without providing a dedicated lower surface support portion.

[0085] In this embodiment, the central chuck 20 is a Bernoulli chuck. Although a Bernoulli chuck does not have a substrate holding force large enough to withstand high-speed rotation, it is sufficient for holding the substrate W during liquid processing that does not require high-speed rotation of the substrate W, and has the advantage of being able to hold the substrate W with the outer peripheral side surface of the substrate W released. On the other hand, in the drying step, the substrate W is also held by the outer periphery chuck 30, so the drying process time can be shortened by rotating the substrate W at high speed. In addition, the contribution of the Bernoulli chuck to holding the substrate W reduces the pressing force of the gripping members 32 of the outer periphery chuck 30 against the outer peripheral side surface of the substrate, thereby preventing damage to the outer periphery of the substrate W.

[0086] 8A to 8D are cross-sectional views illustrating another embodiment of the present invention, showing another example of the configuration of the hybrid chuck 10. In this embodiment, the hybrid chuck 10 has a configuration similar to that of the above-described embodiment, and includes a peripheral chuck 30 and a central chuck 20A configured as a vacuum chuck. The central chuck 20A configured as a vacuum chuck is configured to hold the substrate W in a horizontal position at the center of the lower surface of the substrate W, and is combined and integrated with the peripheral chuck 30 so as to share a rotation axis A to form the hybrid chuck 10. Either the central chuck 20A or the peripheral chuck 30 can hold the substrate W in a horizontal position, or both of them can hold the substrate W in a horizontal position.

[0087] A central chuck 20A, which is a vacuum chuck, is mounted in the central portion of the peripheral base 31. The central chuck 20A is equipped with a suction head 60 mounted in the central portion of the peripheral base 31. The suction head 60 has a plurality of suction holes 61 opening in a suction surface 60a facing the center of the lower surface of the substrate W, and a suction flow path 62 communicating with the suction holes 61. The suction flow path 62 is connected to a vacuum suction device 66 via a suction path 63 formed in the hollow shaft 12 and a suction pipe 64 connected thereto. A suction valve 65 is installed in the suction pipe 64, and the opening and closing of this suction valve 65 is controlled by the controller 8.

[0088] An example of the substrate processing is generally similar to that in the above-described embodiment, and will be described below with reference to FIG.

[0089] The substrate W to be processed is carried into the processing unit 5 by the center robot 6 (step S1) and handed over to the peripheral chuck 30. The substrate W handed over to the gripping members 32 is supported in a horizontal position by the lower surface support portions 34 of the gripping members 32 abutting against the lower surface of the outer periphery of the substrate W. At this time, as shown in FIG. 8A, the gripping members 32 are in an open state and positioned at an upper position. Also, suction by the suction head 60 is stopped, and therefore the central chuck 20A (Bernoulli chuck) is in an inactive state (non-suction state, non-holding state).

[0090] Next, under the control of the cam drive mechanism 51, the gripping members 32 are lowered to the lower position while the substrate W is supported by the lower surface support parts 34 (step S2). Furthermore, under the control of the cam drive mechanism 51, the gripping members 32 are closed, and the side surface abutment parts 33 of the gripping members 32 abut against the outer peripheral side surfaces of the substrate W. This results in alignment of the center of the substrate W with the rotation axis A, i.e., centering (step S3; see FIG. 8B).

[0091] Next, the controller 8 opens the suction valve 65 to start suction by the suction head 60, thereby bringing the central chuck 20A (vacuum chuck) into an operating state (suction state, holding state) (step S4; see FIG. 8C). Then, the controller 8 controls the cam drive mechanism 51 to bring the gripping members 32 into an open state (non-holding state), thereby releasing the gripping by the peripheral chuck 30. As a result, the substrate W is transferred from the peripheral chuck 30 to the central chuck 20A, and the substrate W is held only by the central chuck 20A. At this time, the gripping members 32 are not in contact with either the side or bottom surface of the outer periphery (bevel) of the substrate W, and the substrate W is held by the central chuck 20A in a bevel-free state. If necessary, the gripping members 32 may be slightly lowered to ensure a gap between the bottom surface of the outer periphery of the substrate W and the bottom support member 34.

[0092] In this manner, with the substrate W held only by the central chuck 20A, liquid processing is performed by supplying a processing liquid to the surface of the substrate W while the substrate W is being rotated (step S5, liquid processing step; see FIG. 8C). That is, the substrate rotation mechanism 11 is controlled to rotate the hybrid chuck 10, thereby rotating the substrate W around the rotation axis A at a predetermined liquid processing rotation speed (e.g., 800 rpm). In addition, the processing liquid valve 17 is opened, causing the processing liquid nozzle 15 to eject the processing liquid toward the surface (here, the upper surface) of the substrate W. After the liquid processing is performed for a predetermined liquid processing time, ejection of the processing liquid from the processing liquid nozzle 15 is stopped.

[0093] Next, at the start of the drying step in which the substrate W is rotated around the rotation axis A at a predetermined drying rotation speed (for example, 2500 rpm) to shake off the liquid, the controller 8 controls the cam drive mechanism 51 to control the gripping members 32 to a closed state (holding state). That is, the side abutment portions 33 of the gripping members 32 abut against the side surfaces of the outer periphery of the substrate W, and the outer periphery chuck 30 begins to hold the substrate. That is, the substrate W is held at the center of its lower surface by the central chuck 20A, and at the outer periphery by the outer periphery chuck 30 (step S6; see FIG. 8D).

[0094] The controller 8 controls the cam drive mechanism 51 to execute pressing force control to adjust the pressing force (step S8). More specifically, the pressing force is controlled by controlling the torque generated by the electric motor 53. The pressing force is controlled to a value smaller than the assumed pressing force required when the substrate W is not held by the central chuck 20A but is held only by the peripheral chuck 30 and rotated at the drying rotation speed. That is, the torque generated by the electric motor 53 is controlled so that such pressing force is achieved.

[0095] While controlling the pressing force in this way, the drying process is carried out (step S8). That is, the controller 8 controls the substrate rotation mechanism 11 to accelerate the rotation speed of the substrate W to the drying rotation speed, and maintains the drying rotation speed for a predetermined drying time. Thereafter, the rotation of the substrate is stopped, and the drying process is completed.

[0096] Next, the controller 8 closes the suction valve 65 to stop suction by the suction head 60, thereby releasing the suction and holding by the central chuck 20A (vacuum chuck) (step S9). As a result, the substrate W is held only by the outer periphery chuck 30, and the substrate W is transferred from the central chuck 20A to the outer periphery chuck 30.

[0097] Thereafter, the controller 8 controls the cam drive mechanism 51 to open the gripping members 32, move the side abutment portions 33 away from the outer peripheral side surfaces of the substrate W, and further raise the gripping members 32 to the raised position while the lower surface support portions 34 support the lower surface of the outer peripheral portion of the substrate W (step S10; see FIG. 8A). Thereafter, the center robot 6 scoops up the processed substrate W from the open gripping members 32 and carries it out (step S11). In this way, the processing of one substrate W is completed.

[0098] By using the central chuck 20A, which is a vacuum chuck, the substrate W can be held with its outer peripheral side surface released, allowing the entire outer peripheral side surface of the substrate to be thoroughly processed in the liquid processing step. Meanwhile, in the drying step, the substrate W is also held by the outer peripheral chuck 30, eliminating the need for the central chuck 20A (vacuum chuck) to strongly suction the central portion of the underside of the substrate W. This allows the substrate W to be rotated at high speed while suppressing the formation of suction marks, thereby shortening the drying process time. Additionally, the central chuck 20A (vacuum chuck) contributes to holding the substrate W, reducing the pressing force of the gripping members 32 of the outer peripheral chuck 30 against the outer peripheral side surface of the substrate, thereby preventing damage to the outer peripheral portion of the substrate W.

[0099] 9A and 9B are diagrams for explaining yet another embodiment of the present invention, showing another example of the configuration of the outer periphery chuck 30. In FIGS. 9A and 9B, parts corresponding to those shown in FIGS. 5A, 5B, and 5C are given the same reference numerals. Note that, although the central chuck 20 is a Bernoulli chuck, the central chuck may also be a vacuum chuck (see FIGS. 8A to 8D).

[0100] The outer peripheral base 31 includes a base plate 41 fixed to the shaft 12 and a base cover 42. The base plate 41 is housed within the base cover 42. A gripping member 32 is coupled to the base plate 41 via a bearing 44A. The gripping member 32 has a shaft 35 that penetrates the base plate 41 in the vertical direction and further penetrates the top surface 43 of the base cover 42 to protrude upward. A lower surface support portion 34 and a side abutment portion 33 are provided at the upper end of the shaft 35. The bearing 44 couples the shaft 35 of the gripping member 32 to the base plate 41 so that the gripping member 32 can rotate about a rotation axis 36. In this embodiment, the gripping member 32 is restricted from moving up and down relative to the base plate 41, and therefore does not function as a lift pin. The side abutment portion 33 is erected at a position eccentric from the rotation axis 36. Therefore, the distance between the side surface abutment portion 33 and the outer peripheral side surface of the substrate W changes due to the rotation of the gripping member 32 around the rotation axis .

[0101] A gripping member drive mechanism 45 is provided for rotating the gripping member 32 about the rotation axis 36. The gripping member drive mechanism 45 includes a cam mechanism 46 and a cam drive mechanism 51 that applies a drive force to the cam mechanism 46.

[0102] The cam mechanism 46 includes a cam follower 47A fixed to the lower end of the shaft portion 35 of the gripping member 32, and a cam lever 49 coupled to the cam follower 47A. The cam lever 49 is housed in the base cover 42 and is movable up and down below the base plate 41. The cam follower 47A has a cam groove 48 that is inclined relative to the vertical direction, and a drive end 50 of the cam lever 49 is coupled to this cam groove 48. A compression coil spring 56 that presses down the cam lever 49 is arranged between the cam lever 49 and the lower surface of the base plate 41.

[0103] The cam drive mechanism 51 is disposed in a non-rotating system outside the base cover 42. The cam drive mechanism 51 includes a ball screw mechanism 52, an electric motor 53 that provides driving force to the ball screw mechanism 52, and a drive rod 54 that is moved up and down by the ball screw mechanism 52. A ring-shaped lift plate 57 that surrounds the rotation axis A is connected to the upper end of the drive rod 54. A ring-shaped ball bearing 58 that surrounds the rotation axis A is disposed between the lift plate 57 and the cam lever 49. One raceway ring of the ball bearing 58 is connected to the lift plate 57, and the other raceway ring faces the cam lever 49 so as to be able to abut against it.

[0104] When the cam drive mechanism 51 is driven to raise the lifting plate 57, the ball bearing 58 rises and contacts the cam lever 49. Further raising the lifting plate 57 transmits the driving force to the cam lever 49 via the ball bearing 58, as shown in FIG. 9B , compressing the compression coil spring 56 and raising the cam lever 49. Then, the drive end 50 of the cam lever 49 moves within the cam groove 48 of the cam follower 47A, displacing the cam follower 47A radially outward. This causes the gripping member 32 to rotate about the rotation axis 36. This shortens the distance between the side abutment portion 33 and the rotation axis A, bringing the side abutment portion 33 closer to the outer peripheral side surface of the substrate W. This allows the side abutment portion 33 to contact the outer peripheral side surface of the substrate W and press the side abutment portion 33 against the outer peripheral side surface of the substrate W. In other words, the gripping member 32 can be placed in a closed state. The pressing force of the side surface abutment portion 33 against the outer peripheral side surface of the substrate W can be continuously varied by changing the driving force applied from the cam driving mechanism 51 including the ball screw mechanism 52.

[0105] On the other hand, when the lifting plate 57 is lowered by the cam drive mechanism 51, the compression coil spring 56 presses down the cam lever 49. This causes the drive end 50 of the cam lever 49 to move downward within the cam groove 48, displacing the cam follower 47A radially inward. As a result, as shown in FIG. 9A , the side abutment portion 33 is displaced in a direction away from the rotation axis A and away from the outer peripheral side surface of the substrate W. This allows the gripping member 32 to be in the open state.

[0106] The position of the substrate W when the gripping member 32 supports the substrate W on the lower surface support portion 34 is a transfer position where the substrate W is handed over between the hand 6a of the center robot 6 (substrate transport robot) and the hybrid chuck 10 (more specifically, the outer periphery chuck 30). This position is also a position where the substrate W can be held by the central chuck 20. Therefore, as shown in Fig. 9A, the substrate W can be held at the center of the lower surface of the substrate W by the central chuck 20, and the substrate W can be held at the outer periphery of the substrate W by the outer periphery chuck 30.

[0107] Although the embodiment of the present invention has been described above, the present invention can be embodied in other forms.

[0108] For example, in the above-described embodiment, the gripping member 32 has the side contact portion 33 and the lower surface support portion 34 , but the lower surface support portion may be formed of a member separate from the gripping member 32 .

[0109] In the above-described embodiment, the cam drive mechanism 51 is configured to continuously change the pressing force of the gripping members 32 against the outer peripheral side surface of the substrate. However, the pressing force may be changed in steps. In this case, the drive source of the cam drive mechanism 51 may be an air cylinder. The pressing force does not necessarily have to be variable, and the pressing force of the gripping members 32 in the closed state may be designed to be smaller than the expected pressing force required when the substrate W is held by only the outer periphery chuck 30 and rotated at the drying rotation speed.

[0110] In addition, various design modifications can be made within the scope of the claims. [Explanation of symbols]

[0111] 5: Processing unit (substrate processing device) 8: Controller 10: Hybrid chuck 11: Substrate rotation mechanism 12: Shaft 13:Through hole 14: Electric motor 15: Processing liquid nozzle 16: Processing liquid piping 17: Processing liquid valve 19: Bottom nozzle 20: Central chuck 20A: Central chuck 21: Central Base 22: Gas supply unit 23: Gas outlet 24: Gas flow path 25: Gas supply source 26: Gas supply line 26a: Gas outlet 27: Gas piping 28: Gas valve 30: Periphery chuck 31: Periphery base 32: Grip member 33: Side contact part 34: Bottom support part 45: Grip member drive mechanism 46: Cam mechanism 47: Cam follower 47A: Cam follower 48: Cam groove 49: Cam lever 51: Cam drive mechanism 52: Ball screw mechanism 53: Electric motor 54: Drive rod 55: Compression coil spring 56: Compression coil spring 57: Lifting board 58: Ball bearing 60: Suction head 60a: Adsorption surface 61: Suction hole 62: Suction channel 63: Suction path 64:Suction piping 65: Suction valve 66:Vacuum suction device 100: Substrate processing system A: Rotation axis W: Substrate

Claims

1. a liquid processing step of supplying a processing liquid to the surface of the substrate while holding the substrate horizontally with a central chuck that holds the substrate at the center of the lower surface of the substrate; a drying process for shaking off liquid on the surface of the substrate by rotating the substrate about a rotation axis along a vertical direction while holding the substrate horizontally with the central chuck and gripping the substrate at its outer periphery with a peripheral chuck having a plurality of gripping members each having a side abutment portion that abuts against the side surface of the outer periphery of the substrate.

2. 2. The substrate processing method according to claim 1, wherein the side contact portion of the gripping member is retracted from the outer peripheral side surface of the substrate during the liquid processing step, and is brought into contact with the outer peripheral side surface of the substrate during the drying step.

3. a centering step of bringing the side contact portion of the gripping member into contact with a side surface of an outer periphery of the substrate to center the substrate; 3. The substrate processing method of claim 1, wherein after the centering step, the side contact portion of the gripping member is retracted from the outer periphery of the substrate, and the liquid processing step is performed in a non-contact state in which the side contact portion of the gripping member is not in contact with the substrate.

4. 3. The substrate processing method of claim 1, wherein in the drying step, the substrate is rotated around the rotation axis at a predetermined drying rotation speed, and the side contact portion of the gripping member is pressed against the outer peripheral side surface of the substrate with a pressing force that is smaller than the expected pressing force required when the substrate is held by the outer peripheral chuck rather than by the central chuck and rotated at the drying rotation speed.

5. 3. The substrate processing method according to claim 1, further comprising a lifting step of moving a lower surface support portion, which is in contact with a lower surface of an outer periphery of the substrate, up and down relative to the central chuck while supporting the substrate from below with the lower surface support portion.

6. The substrate processing method according to claim 5 , wherein the gripping member has the lower surface support portion.

7. The method of claim 1 or 2, wherein the central chuck comprises a Bernoulli chuck.

8. The substrate processing method of claim 1 or 2, wherein the central chuck comprises a vacuum chuck.

9. a hybrid chuck in which a central chuck for holding a substrate at a central portion of a lower surface of the substrate and a peripheral chuck having a plurality of gripping members for contacting a side surface of an outer periphery of the substrate are arranged to share a predetermined rotation axis along a vertical direction; a lifting mechanism that moves the gripping member up and down relative to the central chuck; an opening / closing mechanism that displaces the gripping member between a closed state in which the gripping member abuts against a side surface of an outer periphery of the substrate and an open state in which the gripping member is retracted from the side surface of the outer periphery of the substrate.

10. The substrate processing apparatus according to claim 9 , wherein the gripping member has a side contact portion that contacts a side surface of the outer periphery of the substrate, and a lower surface support portion that contacts a lower surface of the outer periphery of the substrate.

11. a controller for controlling the lifting mechanism and the opening / closing mechanism; The controller The substrate processing apparatus according to claim 10 , wherein the gripping member is moved up and down relative to the central chuck in a state where the substrate is supported from below by the lower surface support portion.

12. The controller further controls the central chuck; 12. The substrate processing apparatus of claim 11, wherein the controller centers the substrate by abutting the side contact portion of the gripping member against the outer peripheral side surface of the substrate, then retracts the side contact portion from the outer peripheral side surface of the substrate, and then causes the substrate to be held by the central chuck.

13. a processing liquid nozzle for supplying a processing liquid to the substrate held by the hybrid chuck; a controller for controlling the central chuck and the peripheral chuck; The controller In a liquid processing step in which a processing liquid is supplied from the processing liquid nozzle to the substrate held by the hybrid chuck, the central chuck is controlled to a holding state in which the substrate is held, and the outer peripheral chuck is controlled to a non-holding state in which the central chuck is not in contact with the substrate, 11. The substrate processing apparatus according to claim 9, wherein, in a drying process in which the supply of processing liquid from the processing liquid nozzle is stopped and the substrate is rotated around the rotation axis at a predetermined drying rotation speed to dry the substrate, both the central chuck and the outer periphery chuck are controlled to a holding state in which they hold the substrate.

14. 14. The substrate processing apparatus of claim 13, wherein the controller controls the opening and closing mechanism so that, in the drying process, the substrate is rotated around the rotation axis at the drying rotation speed, and the gripping member is pressed against the outer peripheral side of the substrate with a pressing force that is smaller than an assumed pressing force required when the substrate is held by the outer peripheral chuck instead of the central chuck and rotated at the drying rotation speed.

15. The substrate processing apparatus according to claim 14 , wherein the opening and closing mechanism is capable of varying the pressing force of the gripping member against the outer peripheral side surface of the substrate.

16. The substrate processing apparatus of claim 9 or 10, wherein the central chuck comprises a Bernoulli chuck.

17. The substrate processing apparatus of claim 9 or 10, wherein the central chuck comprises a vacuum chuck.

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