Substrate holding device, substrate processing apparatus, and substrate holding method

Abstract

To prevent dust emission from suction pads and wear of the suction pads in a substrate holding device that suction-holds a substrate on a mounting table by the suction pads in a state of positioning the substrate at a predetermined position with respect to the mounting table, and in the substrate processing apparatus using the substrate holding device.SOLUTION: A substrate holding device comprises: a mounting table having a mounting surface on which a substrate is placed; a lifting / lowering unit that places the substrate on the mounting surface by lowering a plurality of support pins supporting the substrate from below; a suction unit that holds the substrate placed on the mounting surface by suctioning a peripheral portion of the substrate from below with suction pads; a positioning unit that positions the substrate by abutting against an end face of the substrate supported by the plurality of support pins at a positioning position located above and spaced from the suction pads; and a control unit that controls the lifting / lowering unit, the suction unit, and the positioning unit. The substrate positioned by the positioning unit is placed on the mounting surface by the lifting / lowering unit and suction-held by the suction unit.SELECTED DRAWING: Figure 6C

Description

[Technical Field]

[0001] The present invention relates to a substrate holding technology for holding glass substrates for FPDs such as liquid crystal display devices and organic EL display devices, semiconductor wafers, glass substrates for photomasks, substrates for color filters, substrates for recording disks, substrates for solar cells, substrates for electronic paper and other precision electronic device substrates, and substrates for semiconductor packages (hereinafter simply referred to as "substrates") on a mounting table, and a substrate processing technology for supplying and applying a processing liquid from a slit nozzle to a substrate held on the mounting table. [Background technology]

[0002] One known example of a substrate processing apparatus is a coating apparatus that applies a processing liquid to a substrate by discharging a processing liquid from a slit nozzle having a slit-shaped discharge port while moving the slit nozzle relative to the substrate. For example, in the apparatus described in Patent Document 1, a substrate is held on a stage surface (corresponding to an example of a "mounting surface" in the present invention) of a stage, and a slit nozzle is moved above the stage surface to apply the processing liquid to the substrate. In this apparatus, suction cups (corresponding to an example of a "suction pad" in the present invention) are disposed near the surface of the stage to suction-hold the underside of the corners of the substrate. The suction cups are connected to an exhaust means such as a vacuum pump or an exhaust fan. Therefore, by exhausting air from the suction cups, the underside of the corners of the substrate is suction-held by the suction cups. Then, the processing liquid discharged from the slit nozzle is applied to the substrate held by the suction cups. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-192980 [Patent Document 2] Japanese Patent Application Publication No. 2017-112197 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the substrate placement position on the stage surface is preset, and if the substrate deviates from this placement position, the processing liquid cannot be applied properly. Therefore, it has been proposed to incorporate a positioning unit or position adjustment mechanism into the substrate processing apparatus, which adjusts the position of the substrate before the substrate is suction-held by the suction cups. For example, the invention described in Patent Document 2 can be applied as the positioning unit. This position adjustment mechanism has multiple alignment pins. These alignment pins are arranged to surround the substrate supported from below by the suction cups. Each alignment pin is arranged to be movable horizontally toward the substrate. When the multiple alignment pins move toward the substrate and abut against the periphery of the substrate, the substrate is positioned at a preset position (alignment process).

[0005] Simply combining the inventions described in Patent Documents 1 and 2 in this way results in the following problem: During the above-mentioned positioning process, each suction cup is in contact with the substrate. As a result, the alignment pins cause the substrate to move horizontally while rubbing against the suction cups. This horizontal movement causes dust to be emitted from the suction cups and wear to the suction cups, resulting in a decrease in the quality of substrate processing.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to prevent dust generation from suction pads and wear of suction pads in a substrate holding device that uses suction pads to hold a substrate on a mounting table while the substrate is positioned at a predetermined position relative to the mounting table, and in a substrate processing apparatus that uses the substrate holding device. [Means for solving the problem]

[0007] A first aspect of the present invention is a substrate holding device comprising: a mounting table having a mounting surface on which a substrate is placed; a lifting unit that places the substrate on the mounting surface by lowering a plurality of support pins that support the substrate from below; an adsorption unit that adsorbs and holds the peripheral edge of the substrate placed on the mounting surface from below using an adsorption pad; a positioning unit that positions the substrate by abutting against the edge surface of the substrate supported by the plurality of support pins at a positioning position spaced above the adsorption pad; and a control unit that controls the lifting unit, adsorption unit, and positioning unit so that the substrate positioned by the positioning unit is placed on the mounting surface by the lifting unit and adsorbed and held by the adsorption unit.

[0008] A second aspect of the present invention is a substrate processing apparatus comprising the substrate holding device described above, and a slit nozzle that applies a processing liquid to the surface of the substrate by moving horizontally relative to the substrate placed on the mounting surface and held by suction on the mounting table by an suction pad.

[0009] In addition, a third aspect of the present invention is a substrate holding method characterized by comprising: a first step of adsorbing and holding a substrate on a mounting surface of a mounting table using an adsorption pad of an adsorption section; a second step prior to the first step of positioning the substrate by abutting a positioning member against an edge surface of the substrate while supporting the substrate from below using a plurality of support pins above the mounting surface and the adsorption pad; and a third step after the second step of lowering the plurality of support pins to place the substrate on the mounting surface.

[0010] In the invention configured as described above, the substrate is supported by a plurality of support pins from below at a positioning position spaced above the suction pads, and the positioning member abuts against the edge of the substrate. This positions the substrate horizontally. During this positioning process, the substrate is moved horizontally without abutting the suction pads. The positioned substrate is then placed on the placement surface by the lifting unit and held by suction by the suction unit. [Effects of the Invention]

[0011] As described above, according to the present invention, the substrate can be positioned at a predetermined position on the mounting table and held by suction on the mounting table using the suction pad, while preventing dust generation from the suction pad and wear on the suction pad. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram schematically illustrating an overall configuration of a coating apparatus that is an embodiment of a substrate processing apparatus according to the present invention. [Figure 2] FIG. 2 is a plan view of the main part of the substrate holding mechanism as viewed from above. [Figure 3] FIG. 2 is a diagram schematically illustrating the configuration of a substrate holding mechanism. [Figure 4] 10 is a flowchart showing an example of a substrate holding process in the substrate processing apparatus of FIG. [Figure 5] 3 is a flowchart showing a procedure for provisionally straightening a substrate by the substrate holding mechanism of FIG. 2. [Figure 6A] 5 is an explanatory diagram showing the operations executed according to the flowchart of FIG. 4. [Figure 6B] 6 is an explanatory diagram showing the operations executed according to the flowchart of FIG. 5. [Figure 6C] 5 is an explanatory diagram showing the operations executed according to the flowchart of FIG. 4. [Figure 6D] 5 is an explanatory diagram showing the operations executed according to the flowchart of FIG. 4. [Figure 6E] 5 is an explanatory diagram showing the operations executed according to the flowchart of FIG. 4. DETAILED DESCRIPTION OF THE INVENTION

[0013] Fig. 1 is a diagram showing a schematic diagram of the overall configuration of a coating apparatus, which is one embodiment of a substrate processing apparatus according to the present invention. In Fig. 1 and the following figures, an XYZ Cartesian coordinate system is appropriately added in which the Z direction is the vertical direction and the XY plane is the horizontal plane in order to clarify the directional relationships between them, and the dimensions and number of each part are exaggerated or simplified as necessary.

[0014] The substrate processing apparatus 100 is equipped with a substrate holding mechanism 200, which is an example of a "substrate holding device" according to the present invention. A control unit 10 controls each component of the substrate processing apparatus 100. With the substrate S held by the substrate holding mechanism 200, the slit nozzle 1 moves relative to the substrate S in the X direction, thereby applying a treatment liquid to the surface Sa of the substrate S. In other words, the substrate processing apparatus 100 is an apparatus called a slit coater. The treatment liquid may be, for example, a photoresist liquid, a color filter pigment, a polyimide precursor, a silicone agent, nanometal ink, or a paste or slurry containing a conductive material. The substrate S is a glass substrate having a rectangular shape in a plan view. The substrate S to be coated may also be a rectangular glass substrate, a semiconductor substrate, a flexible substrate for a film liquid crystal display, a substrate for a photomask, a substrate for a color filter, a substrate for a solar cell, a substrate for an organic electroluminescence (EL) display, or a substrate for a semiconductor package. In this specification, the "surface Sa of the substrate S" refers to the principal surface of the substrate S to which the treatment liquid is applied.

[0015] In the substrate processing apparatus 100, a stage 3, which is one component of a substrate holding mechanism 200, is disposed on a base 2. A substrate S is placed on an upper surface (hereinafter referred to as a "mounting surface 31") of the stage 3 and is held by suction. The configuration and operation of the substrate holding mechanism 200 will be described in detail later.

[0016] A slit nozzle 1 is disposed above the stage 3. The slit nozzle 1 has a slit-shaped outlet extending in the Y direction, and is capable of discharging a processing liquid from the outlet toward the surface Sa of a substrate S held on the stage 3. The substrate processing apparatus 100 is provided with a nozzle movement unit 4 that moves the slit nozzle 1 back and forth in the X direction above the stage 3. The nozzle movement unit 4 has a bridge-structured nozzle support 41 that crosses above the stage 3 in the Y direction and supports the slit nozzle 1, and a nozzle drive mechanism 42 that moves the nozzle support 41 horizontally in the X direction.

[0017] The nozzle support 41 has a fixed member 41a to which the slit nozzle 1 is fixed, and two lifting units 41b that support and raise and lower the fixed member 41a. The fixed member 41a is a rod-shaped member with a rectangular cross section whose longitudinal direction is in the Y direction and is made of carbon fiber reinforced resin or the like. The two lifting units 41b are connected to both longitudinal ends of the fixed member 41a and each have an AC servo motor, a ball screw, or the like. These lifting units 41b raise and lower the fixed member 41a and the slit nozzle 1 together in the vertical direction (Z direction), adjusting the distance between the outlet of the slit nozzle 1 and the substrate S, i.e., the relative height of the outlet with respect to the top surface of the substrate S.

[0018] The nozzle drive mechanism 42 includes two guide rails 43 that guide the movement of the slit nozzle 1 in the X direction, two linear motors 44 that serve as drive sources, and two linear encoders 45 that detect the position of the outlet of the slit nozzle 1. The two guide rails 43 are arranged at both ends of the base 2 in the Y direction so as to sandwich the stage 3 in the Y direction, and extend in the X direction so as to include the stage 3. The lower ends of the two lifting / lowering units 41b are guided along the two guide rails 43, respectively, so that the slit nozzle 1 moves in the X direction above the substrate S held on the stage 3.

[0019] Each of the two linear motors 44 is an AC coreless linear motor having a stator 44a and a slider 44b. The stators 44a are provided along the X direction on both Y-direction sides of the base 2. Meanwhile, the slider 44b is fixed to the outside of the lifting unit 41b. The linear motor 44 functions as a drive source for the nozzle driving mechanism 42 by the magnetic force generated between the stator 44a and slider 44b.

[0020] Each of the two linear encoders 45 includes a scale unit 45a and a detector 45b. The scale unit 45a is provided along the X direction below a stator 44a of a linear motor 44, which is fixed to the base 2. The detector 45b is fixed further outward from a slider 44b of the linear motor 44, which is fixed to the lift unit 41b, and is disposed opposite the scale unit 45a. The linear encoder 45 detects the position of the outlet of the slit nozzle 1 in the X direction based on the relative positional relationship between the scale unit 45a and the detector 45b. That is, in this embodiment, the lift unit 41b adjusts the distance between the slit nozzle 1 and the substrate S in the Z direction, while the nozzle drive mechanism 42 moves the slit nozzle 1 relative to the substrate S in the X direction. During this relative movement, a treatment liquid is discharged from the slit nozzle 1, thereby supplying the treatment liquid to the upper surface of the substrate S (treatment liquid application process).

[0021] Fig. 2 is a plan view of the main parts of the substrate holding mechanism as seen from above, and Fig. 3 is a diagram showing a schematic configuration of the substrate holding mechanism. The configuration and operation of substrate holding mechanism 200 will be described with reference to these drawings.

[0022] In the substrate holding mechanism 200, the stage 3 corresponds to an example of the "mounting table" of the present invention. A stone surface plate or the like having a mounting surface 31 with a flatness of about several micrometers is used as the stage 3. The center of the mounting surface 31 functions as a substrate mounting area 311 on which the substrate S can be mounted. The substrate mounting area 311 has a central portion in which a lattice-shaped suction grooves 312 are provided corresponding to the effective area of ​​the substrate S, and a peripheral portion in which a plurality of suction pads 71 ​​are arranged to surround the suction grooves 312.

[0023] Here, the effective area of ​​the substrate S refers to an area in the center of the upper surface of the substrate S where multiple elements are provided. For example, in the case of a semiconductor package, a rectangular glass substrate corresponds to the substrate S, and multiple semiconductor chips stacked and arranged in the center of the upper surface of the glass substrate, as well as the wiring between the chips, correspond to the multiple elements. When the substrate S is placed on the substrate placement area 311, the effective area is located above the center of the substrate placement area 311. In the center of the substrate placement area 311, suction grooves 312 are engraved in a grid pattern as shown in FIG. 2 to firmly suction-hold the effective area of ​​the substrate S on the placement surface 31. That is, grooves are extended in the X and Y directions at a certain depth from the placement surface 31, and through-holes 313 are drilled in the Z direction at some of the points where the grooves intersect, leading from the intersections to the underside 32 of the stage 3.

[0024] As shown in FIG. 3 , each through-hole 313 is connected to a negative pressure generator 5. The negative pressure generator 5 includes a suction pipe 51, a suction source 52, and an on-off valve 53. More specifically, the suction source 52 is connected to the through-hole 313 via the suction pipe 51. The suction source 52 may be, for example, a vacuum pump or a utility power source of a factory in which the substrate processing apparatus 100 is installed. An on-off valve 53 is interposed in the suction pipe 51. The on-off valve 53 closes in response to a close command from the control unit 10, thereby stopping the supply of negative pressure to the through-hole 313. On the other hand, the on-off valve 53 opens in response to an open command from the control unit 10, thereby supplying negative pressure to the through-hole 313. That is, as will be described later, after the substrate S is placed in the substrate placement area 311, when the on-off valve 53 opens in response to an open command from the control unit 10, negative pressure is supplied to the through-hole 313. As a result, air is discharged from the space between the lower surface of the effective area of ​​the substrate S and the placement surface 31 through the suction grooves 312 and through holes 313, and the substrate S is held by suction on the placement surface 31.

[0025] In this way, the effective area of ​​the substrate S is suction-held by the negative pressure generator 5, but the area outside the effective area, i.e., the non-effective area, is located above the periphery of the substrate placement area 311. Therefore, if warping occurs in the non-effective area, air will flow from the warped portion into the exhaust target space (between the effective area and the stage 3), reducing the suction force. Therefore, in this embodiment, a plurality of recesses are provided on the placement surface 31 around the periphery of the substrate placement area 311 so as to surround the lattice-shaped suction grooves 312, and a suction pad 71 is disposed in each recess. As shown in FIG. 3 , the suction pad 71 has an upper suction end provided with suction ports 711 that suction-hold the lower surface Sb of the substrate S, and a lower suction end embedded in the recess. This lower suction end is connected to the negative pressure generator 5, similar to the suction grooves 312. Therefore, when the on-off valve 53 closes in response to a closing command from the control unit 10, the supply of negative pressure to the suction pad 71 is stopped. At this time, the suction upper end of the suction pad 71 protrudes about 1 mm above the placement surface 31, and is able to support the peripheral edge of the substrate S from below while remaining in a non-suction state. The height position of the suction port 711 at this time (reference symbol H3 in FIG. 6B, which will be described later) corresponds to an example of the "pad contact position" of the present invention. Meanwhile, when the on-off valve 53 opens in response to an opening command from the control unit 10, negative pressure is supplied to the suction pad 71, and suction of the substrate S begins.

[0026] The suction pad 71 has a so-called bellows structure and is expandable and contractible in the vertical direction Z. Therefore, after the lower surface of the substrate S abuts against the suction openings 711 of the suction pad 71, that is, after a so-called abutting state is reached, the suction upper end of the suction pad 71, while still in contact with the substrate S, retreats into the recess in conjunction with the descent of the substrate S by the lifting unit 6, which will be described next, and is able to sink into the recess when the substrate S has been placed on the placement surface 31. In this way, in this embodiment, the suction unit 7 is made up of a plurality of suction pads 71, and holds the peripheral edge of the substrate S by suction from below.

[0027] In this embodiment, the suction grooves 312 and the suction pads 71 ​​simultaneously switch between suction and non-suction by opening and closing the on-off valve 53, but it is also possible to provide an on-off valve dedicated to the suction grooves and an on-off valve dedicated to the suction pads so that they can be switched independently.

[0028] The lifting unit 6 has a plurality of lift pins 61 and a lift pin driving unit 62. The stage 3 is provided with a plurality of pin storage holes 315 that extend parallel to the Z direction and open to the mounting surface 31, and a lift pin 61 is stored in each pin storage hole 315. In this embodiment, four pin storage holes 315 are provided, and the substrate S is configured to be raised and lowered by four lift pins 61, but the number of lift pins 61 is not limited to "four" and may be changed as appropriate depending on the planar size and weight of the substrate S, etc.

[0029] Each lift pin 61 has a tip cap made of a resin material detachably attached to the tip of a metal lift pin body such as stainless steel, and has a pin shape extending parallel to the Z direction as a whole. The resin material constituting the tip cap is, for example, PEEK (Poly Ether Ether Ketone) or UPE (Ultra For example, high molecular weight polyethylene (Ultra High Molecular Weight Polyethylene) can be used. The tip of each lift pin 61, i.e., the tip cap, comes into contact with the underside of the substrate S as will be explained below, and wears out as the number of contacts increases. Therefore, as wear progresses, the tip cap is periodically replaced by the operator.

[0030] When the control unit 10, which controls the entire apparatus, issues a lift-up / down command to the lift pin drive unit 62, the lift pins 61 are raised and lowered. This causes the lift pins 61 to advance and retreat relative to the pin storage holes 315. As shown in FIG. 3 , the lift pins 61 are raised until their tips reach a height position H1, enabling the transfer of the substrate S to and from a robot (not shown). In other words, height position H1 corresponds to an example of a transfer position for the substrate S. For example, when the robot transports the substrate S above the stage 3, the multiple lift pins 61, which have been raised by the drive of the lift pin drive unit 62, protrude above the mounting surface 31 from the pin storage holes 315, and their upper ends make point contact with the underside of the substrate S to receive the substrate S. Next, the multiple lift pins 61 are lowered by the drive of the lift pin drive unit 62 and fit into the pin storage holes 315, allowing the substrate S to be mounted in the substrate mounting area 311 from the upper ends of the multiple lift pins 61. When the substrate S is lifted from the substrate placement area 311 , the lift pin drive unit 62 drives the lift pins 61 to rise and protrude from the pin housing holes 315 above the placement surface 31 .

[0031] In this embodiment, a positioning position (H2 in FIG. 6B) is set midway in the vertical direction Z between the delivery position (H1 in FIGS. 3 and 6A) and the pad contact position (H3 in FIG. 6B). The reason for providing this positioning position is to allow the positioning unit 8 to position the substrate S received from the robot before the coating process in the horizontal direction while avoiding sliding contact with the suction pad 71 (position adjustment process). In this embodiment, a pressing unit 9 is provided to perform a warpage correction process for correcting warpage of the substrate S simultaneously with, before, or after the position adjustment process.

[0032] In this embodiment, the positioning unit 8 and the pressing unit 9 have the same configurations as the position adjustment mechanism and the pressing mechanism described in Patent Document 2. Therefore, in the following, detailed configuration descriptions of the positioning unit 8 and the pressing unit 9 will be omitted, and their general configurations will be described with reference to Figures 2 and 3.

[0033] The positioning unit 8 has a total of eight position adjustment devices 81, two of which are arranged on each side of the mounting surface 31. Each position adjustment device 81 has pin-shaped alignment pins 82 extending parallel to the Z direction. That is, two alignment pins 82 are arranged on each side of the stage 3, spaced apart from each other in the horizontal direction. The alignment pins 82 are arranged above the mounting surface 31 and are horizontally movable between the space above the stage 3 and a space spaced apart from the upper space and outside the stage. More specifically, as shown in FIG. 3, the lower ends of the alignment pins 82 are located higher than the mounting surface 31 and lower than the pad contact position (H3 in FIG. 6B). Meanwhile, the upper ends are located higher than the positioning position (H2 in FIG. 6B) and lower than the transfer position (H1 in FIGS. 3 and 6A). Therefore, when the substrate S is positioned at the positioning position, the alignment pins 82 face the edge surface Se of the substrate S in the horizontal direction.

[0034] An alignment pin driver 83 is connected to the alignment pin 82 configured in this manner. When the alignment pin driver 83 operates in response to a positioning command from the control unit 10, the alignment pin 82, which has been positioned at the retracted position, moves horizontally toward the substrate S at the positioning position and abuts against the edge surface Se of the substrate S. This positions the substrate S at a predetermined position in the horizontal direction (this may be referred to as a position adjustment process or an alignment process). After this position adjustment process, when a retraction command is given to the alignment pin driver 83 from the control unit 10, the alignment pin 82 moves away from the substrate S and returns to the retracted position.

[0035] The pressing unit 9 has a total of four pressing means 91, one on each side of the mounting surface 31. Each pressing means 91 has a pressing member 92 extending along the corresponding side of the mounting surface 31. Each pressing member 92 is movable between a standby position, a temporary correction position, and a final correction position. The standby position refers to the position of the pressing member 92 when the substrate S is being loaded or unloaded, when the substrate S is waiting to be loaded, and during the coating process. As shown in FIG. 3, while the pressing member 92 is positioned at the standby position away from the substrate mounting area 311, it does not interfere with the substrate S being loaded or unloaded, allowing for smooth loading and unloading of the substrate S. Furthermore, during the coating process, it is away from the substrate S, preventing interference with the slit nozzle 1 and allowing for smooth coating.

[0036] The temporary correction position refers to a position where the peripheral edge of the substrate S located at the positioning position is pressed from above (see FIGS. 6B to 6C, which will be described later). That is, at this temporary correction position, the lower surface of the pressing member 92 covers the peripheral edge of the substrate S from above, and the substrate S is located at the positioning position (reference symbol H2 in FIG. 6B) in the vertical direction Z. As a result, even if the peripheral edge of the substrate S located at the positioning position has a shape that conforms to the upward direction, that is, even if the substrate S is warped concavely, the pressing member 92 presses the peripheral edge of the substrate S from above at the temporary correction position to correct the warpage of the substrate S (temporary correction process). As a result, even if the peripheral edge of the substrate S is warped upward when the substrate is carried in, the substrate S undergoes temporary correction at the positioning position and is supported by the multiple lift pins 61 with its end surface Se facing the side surface of the alignment pin 82. Therefore, the positioning process can be performed stably.

[0037] Furthermore, when performing the positioning process, the alignment pins 82 and the pressing members 92 each come into contact with the substrate S. Therefore, in this embodiment, as shown in Fig. 2, the contact area where the alignment pins 82 come into contact with the edge surface Se of the substrate S and the pressing area where the pressing members 92 press the peripheral edge portion of the substrate S are configured to be different from each other in the circumferential direction of the substrate S. As a result, it is possible to smoothly perform the temporary correction process and the positioning process at the positioning position.

[0038] The main correction position refers to a position where the pressing member 92 presses the peripheral edge of the substrate S placed on the placement surface 31 from above toward the placement surface 31 (see FIG. 6E, which will be described later). That is, at the main correction position, the lower surface of the pressing member 92 and the placement surface 31 sandwich the peripheral edge of the substrate S, and corrects the warpage of the substrate S (main correction process).

[0039] Each pressing member 92 is connected to a pressing drive unit 93. When the pressing drive unit 93 operates in response to a command from the control unit 10, the pressing member 92 moves from the standby position to the temporary correction position and the final correction position, and then returns to the standby position. The substrate holding operation, including this series of pressing movement operations, is performed for each substrate S by the control unit 10 controlling each unit of the substrate holding mechanism 200 in accordance with a pre-stored program as described below.

[0040] Fig. 4 is a flowchart showing an example of a substrate holding process in the substrate processing apparatus of Fig. 1. Fig. 5 is a flowchart showing a procedure for temporary correction of a substrate by the substrate holding mechanism of Fig. 2. Figs. 6A, 6C to 6E are operation explanatory diagrams showing the operations executed according to the flowchart of Fig. 4, and Fig. 6B is an operation explanatory diagram showing the operations executed according to the flowchart of Fig. 5.

[0041] In step S101, the pressing members 92 provided corresponding to each of the four sides of the mounting surface 31 move to their standby positions and wait. That is, as shown in FIG. 6A, the pressing members 92 move to a non-interference position L2 that is higher than the delivery position H1 and outside the substrate S transported by a robot (not shown), and wait there. Then, in the next step S102, as shown in FIG. 6A, each alignment pin 82 is positioned in the separation space. Also, the upper ends of the lift pins 61 are accommodated in the pin storage holes 315. When the robot transports the substrate S above the mounting surface 31, as shown by arrow M1 in FIG. 6A, each lift pin 61 rises from the pin storage hole 315, and the upper ends of each lift pin 61 come into point contact with the substrate S at the delivery position H1 (step S103), and each lift pin 61 receives the substrate S from the robot (step S104).

[0042] Then, as indicated by arrow M2 in FIG. 6B, the lift pins 61 are lowered until their upper ends are positioned at positioning position H2. As a result, the substrate S is moved to positioning position H2 with its lower surface supported by the lift pins 61 from below (step S105). That is, the center of the substrate S in the vertical direction Z is approximately aligned with positioning position H2. On the other hand, the peripheral edge of the substrate S does not necessarily coincide with positioning position H2. For example, if the peripheral edge of the loaded substrate S is warped upward, the edge surface Se of the substrate S in the vertical direction Z may be higher than positioning position H2. Furthermore, the distance from positioning position H2 is proportional to the degree of warping of the substrate S. Here, for example, if the amount of warping of the substrate S increases, the edge surface Se of the substrate S may be higher than the upper end of the alignment pin 82. In this case, if the alignment pin 82 is moved horizontally toward the substrate, the alignment pin 82 will directly abut against the lower surface of the substrate S, not the edge surface Se of the substrate S. As a result, the positioning accuracy of the substrate S in the horizontal direction is significantly reduced.

[0043] Therefore, in this embodiment, a temporary correction process for the substrate S shown in FIG. 5 is performed (step S106). That is, the four pressing members 92 are horizontally moved to an advanced position L1, as indicated by arrow M3 in FIG. 6B, and positioned directly above the corresponding edge of the substrate S (step S201). Next, as indicated by arrow M4 in the same figure, each pressing member 92 descends to a positioning position H2 (step S202). At this time, if the peripheral edge of the substrate S is warped upward, the pressing members 92 descending to the positioning position H2 press the warped peripheral edge of the substrate S downward, thereby correcting the warpage of the substrate S to some extent. As a result, the height of the peripheral edge of the substrate S is approximately at the positioning position H2, which is lower than the upper ends of the alignment pins 82. As a result, the side surfaces of the alignment pins 82 face the edge surface Se of the substrate S in the horizontal direction.

[0044] When the temporary correction of the substrate S is completed, as shown by reference symbol M5 in FIG. 6C, the alignment pins 82 move horizontally toward the substrate S at the positioning position, and position the substrate S at a predetermined position in the horizontal direction (step S107: positioning process). Then, after the positioning process, as shown by reference symbol M6 in FIG. 6C, the alignment pins 82 move away from the substrate S and return to their original retracted positions. In this manner, in this embodiment, the positioning process of the substrate S is performed in a state in which the substrate S is spaced upward from the suction pads 71. As a result, the substrate S is positioned at a predetermined position relative to the mounting surface 31 in the horizontal direction, while effectively preventing dust generation from the suction pads 71 ​​and wear of the suction pads 71.

[0045] Subsequently, as shown by arrow M7 in Fig. 6D, the descent of the lift pins 61 is resumed (step S108). As a result, the substrate S is lowered toward the stage 3 while being supported by the lift pins 61. In synchronization with this, the pressing member 92 also lowers toward the stage 3 (step S109). In other words, if the substrate S being lowered has been subjected to the temporary correction process in step S106, the substrate S is lowered while still in the temporarily corrected state.

[0046] During the downward movement, the peripheral edge of the substrate S comes into contact with the suction ports 711 of the suction pads 71 ​​(see FIG. 6D). Furthermore, the lift pins 61 are lowered, and the upper ends of the lift pins 61 are accommodated in the pin storage holes 315, and the suction upper ends of the suction pads 71 ​​are retracted into the recesses. As a result, the substrate S is placed on the placement surface 31 from the upper ends of the lift pins 61 (step S110). The pressing member 92 presses the peripheral edge of the substrate S against the placement surface 31, thereby correcting the shape of the substrate S to conform to the shape of the placement surface 31. In this manner, in this embodiment, the substrate S is placed on the placement surface 31 while the correction process is being performed. Then, the air suction unit 113 sucks air through the air holes, thereby adsorbing the substrate S to the placement surface 31 (step S111). As a result, the substrate S is fixed to the placement surface 31. Subsequently, the pressing member 92 returns to its original standby position. This completes the substrate holding process. Thereafter, the coating process is carried out by the slit nozzle 1.

[0047] As described above, in this embodiment, the alignment pins 82 abut against the edge surface Se of the substrate S while the substrate S is supported from below by the plurality of lift pins 61 at the positioning position H2 spaced above the suction pad 71. As a result, the substrate S is aligned at a predetermined position relative to the mounting surface 31 in the horizontal direction. During this positioning process (alignment process), the substrate S is spaced from the suction pad 71 and is moved horizontally in a non-contact state. After positioning, the substrate S is placed on the mounting surface 31 and is suction-held by the suction pad 71. Therefore, the substrate S can be positioned at a predetermined position relative to the mounting surface 31 and suction-held to the mounting table by the suction pad 71 while preventing dust generation from the suction pad 71 and wear of the suction pad 71.

[0048] Furthermore, before performing the positioning process using the alignment pins 82, a temporary correction process is performed by the pressing unit 9 at the positioning position H2. Therefore, even if a substrate S with a peripheral edge portion warped upward is carried in, the peripheral edge portion of the substrate S in the vertical direction Z is corrected to approximately the same height as the positioning position H2, and the alignment pins 82 can be reliably brought into contact with the edge surface Se of the substrate S. Moreover, in this embodiment, the positioning process (alignment process) using the alignment pins 82 is performed while the peripheral edge portion of the substrate S is being temporarily corrected by pressing the pressing member 92 from above. Therefore, the positioning process using the alignment pins 82 can be performed with high precision.

[0049] Furthermore, in this embodiment, after the substrate S is positioned, the alignment pins 82 move away from the edge surface Se of the substrate S and the lift pins 61 move down to place the substrate S on the placement surface 31. At the same time, the peripheral edge of the substrate S placed on the placement surface 31 is clamped between the placement surface 31 and the pressing member 92 to correct the peripheral edge of the substrate S (main correction process). Then, since the processing liquid is applied to the substrate S after the main correction process, the processing liquid can be applied well to the surface Sa of the substrate S.

[0050] As described above, in the above embodiment, the lift pins 61 correspond to an example of the "support pins" of the present invention, and the alignment pins 82 correspond to an example of the "positioning members" of the present invention.

[0051] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, although the descent speed of the substrate S is arbitrary in the above-described embodiment, the descent speed may be changed based on the pad contact position H3. More specifically, if the speed at which the substrate S descends from the positioning position H2 to the pad contact position H3 and the speed at which the substrate descends from the pad contact position H3 to the mounting surface are defined as a "first descent speed" and a "second descent speed," respectively, the second descent speed may be set to be slower than the first descent speed. This is intended to allow the contraction of the suction pad 71 to follow the descent of the substrate caused by the descent of the lift pins 61 without delay.

[0052] Furthermore, in the above embodiment, suction holding begins after the substrate S is placed on the placement surface 31, but the timing at which suction starts is not limited to this, and suction holding may begin, for example, when the substrate S has descended to the pad abutment position H3.

[0053] Furthermore, in the above embodiment, alignment pin 82 is used as the "positioning member" of the present invention, but the shape of the "positioning member" is not limited to this, and for example, a block body having a pillar shape may be used as an example of the "positioning member". [Industrial Applicability]

[0054] The present invention can be applied to a substrate holding device or substrate holding method that holds a substrate on a mounting table, and can also be applied to a substrate processing apparatus that supplies and applies a processing liquid from a slit nozzle to a substrate held on a mounting table. [Explanation of symbols]

[0055] 1...Slit nozzle 3...Stage (mounting platform) 7...Adsorption part 8... Positioning part 9...Pressing part 10...Control unit 12...Lift pin (support pin) 31...Placement surface (top surface of substrate) 71...Suction pad 82...Alignment pin (positioning member) 92...Pressing member 100...Substrate processing apparatus 200...Substrate holding mechanism (substrate holding device) 711...Suction port H1: Delivery location H2: Positioning position H3: Pad contact position S...Substrate Sa...(substrate) surface Se...(substrate) edge Z: Vertical direction

Claims

1. a mounting table having a mounting surface on which a substrate is placed; a lifting unit that lowers a plurality of support pins that support the substrate from below to place the substrate on the placement surface; a suction unit that suctions and holds a peripheral edge portion of the substrate placed on the placement surface from below using a suction pad; a positioning unit that abuts against an end surface of the substrate supported by the plurality of support pins at a positioning position spaced above the suction pad to position the substrate; a control unit that controls the lifting unit, the suction unit, and the positioning unit so that the substrate positioned by the positioning unit is placed on the placement surface by the lifting unit and is sucked and held by the suction unit; A substrate holding device comprising:

2. 2. The substrate holding device according to claim 1, a substrate holding device including a pressing portion that is provided so as to be able to press from above a peripheral edge portion of the substrate supported by the plurality of support pins at the positioning position;

3. 3. The substrate holding device according to claim 2, A substrate holding device, wherein a contact area where the positioning portion contacts the edge surface of the substrate and a pressing area where the pressing portion presses the peripheral edge of the substrate are different from each other in the circumferential direction of the substrate.

4. 4. The substrate holding device according to claim 3, The control unit controls the positioning unit and the pressing unit so that the substrate is positioned by the pressing unit pressing the peripheral edge of the substrate while the positioning unit abuts against the edge surface of the substrate.

5. 5. The substrate holding device according to claim 4, The control unit controls the positioning unit and the lifting unit so that after positioning the substrate, the positioning unit moves away from the edge surface of the substrate and the lifting unit lowers the multiple support pins, thereby placing the substrate on the placement surface.

6. 6. The substrate holding device according to claim 5, The control unit controls the pressing unit to descend together with the descending of the plurality of support pins, thereby clamping the peripheral edge of the substrate placed on the placement surface between the placement surface and the pressing unit.

7. 7. The substrate holding device according to claim 1, the suction pad has an upper suction end portion provided with a suction port for suctioning the lower surface of the substrate, and a lower suction end portion embedded in a recess provided in the placement surface, The substrate holding device has a structure in which, when not in contact with the underside of the substrate, the suction upper end protrudes above the placement surface to a pad contact position that is lower than the positioning position, and when in contact with the underside of the substrate, the suction upper end retracts into the recess in conjunction with the descent of the substrate, and is free to retract into the recess when the substrate has been placed on the placement surface.

8. 8. The substrate holding device according to claim 7, The control unit controls the lifting unit so that the substrate descends from the positioning position to the pad abutment position at a first descent speed, and also descends from the pad abutment position to the placement surface at a second descent speed slower than the first descent speed.

9. A substrate holding device according to any one of claims 1 to 6; a slit nozzle that is placed on the placement surface and moves horizontally relative to the substrate that is held by suction on the placement table by the suction pad, thereby applying a processing liquid to the surface of the substrate; A substrate processing apparatus comprising:

10. a first step of sucking and holding the substrate on the mounting surface of the mounting table by the suction pad of the suction unit; a second step, prior to the first step, of positioning the substrate by abutting a positioning member against an edge surface of the substrate while supporting the substrate from below with a plurality of support pins above the placement surface and the suction pad; a third step of placing the substrate on the placement surface by lowering the plurality of support pins after the second step; A substrate holding method comprising:

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