Substrate Processing Apparatus and Transfer Control Method Thereof

Abstract

A substrate processing apparatus (1) for transporting a substrate with a liquid film covering the surface of the substrate, in order to prevent the exposure of the substrate surface due to vibrations during transportation or evaporation of the liquid, etc., includes: a first processing unit (11A) that supplies a liquid to the substrate (S) and covers the surface of the substrate with a liquid film; a transport mechanism (15) that transports the substrate carrying the liquid film; a second processing unit (13A) that receives the substrate transported by the transport mechanism and performs a predetermined process; an imaging unit (157) that images the liquid film formed on the substrate surface; and a control unit (90) that controls the operation of the transport mechanism based on the differences between a plurality of images captured by the imaging unit at different times respectively during the period from the formation of the liquid film to the substrate being transported into the second processing unit by the transport mechanism.

Description

Technical Field

[0001] The present invention relates to a substrate processing apparatus for transporting a substrate between a plurality of processing units, and particularly relates to control of transportation in a state where a liquid film is formed on the surface of the substrate. Background Art

[0002] In the manufacturing process of substrates such as semiconductor substrates and glass substrates for display panels, in order to perform different processes by individual processing units respectively, it is necessary to transport the substrate between a plurality of processing units. In this case, it is necessary to prevent the following problems in advance, that is, surface oxidation due to exposure of the substrate surface during transportation, or attachment of suspended matter on the transportation path to the substrate surface, and further collapse of the fine pattern formed on the substrate. Therefore, there are cases where the substrate is transported in a state where the surface of the substrate is covered with a liquid film.

[0003] For example, in the prior art described in Japanese Patent Laid-Open No. 2010-182817 (Patent Document 1), during transportation between processing systems that process substrates with liquids respectively, the substrate is transported in a state of being immersed in the liquid accumulated in the transportation tray or in a state where the entire upper surface is filled with liquid.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Patent Laid-Open No. 2010-182817 Summary of the Invention

[0007] The problem to be solved by the present invention

[0008] During transportation of the substrate, due to acceleration / deceleration or vibration on the transportation path, or reduction of the liquid due to volatilization, etc., it is possible that a part of the substrate surface is exposed to the surrounding environment during transportation. This phenomenon causes product defects. In particular, in a substrate on which a fine pattern is formed, surface exposure immediately causes pattern collapse, so even for a short time, it is not allowed.

[0009] In the above prior art, since the substrate is stored in the transportation tray, a certain degree of stable transportation can be expected, but it does not have a function of preventing temporary exposure of the substrate surface due to vibration, volatilization of the liquid, etc. as described above.

[0010] The present invention is proposed in view of the above problems, and its object is to provide a substrate processing apparatus that transports a substrate in a state where the surface of the substrate is covered with a liquid film, and can prevent exposure of the substrate surface due to vibration or volatilization of the liquid during transportation.

[0011] Means for Solving the Problem

[0012] In order to achieve the above object, one aspect of the substrate processing apparatus of the present invention includes: a first processing unit that supplies a liquid to a substrate and covers the surface of the substrate with a liquid film; a transfer mechanism that transfers the substrate carrying the liquid film; a second processing unit that receives the substrate transferred by the transfer mechanism and performs a predetermined process; an imaging unit that images the liquid film formed on the surface of the substrate; and a control unit that controls the operation of the transfer mechanism based on the differences between a plurality of images captured by the imaging unit at different times during the period from the formation of the liquid film to the transfer of the substrate into the second processing unit by the transfer mechanism.

[0013] In addition, another aspect of the present invention is a transfer control method for a substrate processing apparatus, the substrate processing apparatus having: a first processing unit that supplies a liquid to a substrate and covers the surface of the substrate with a liquid film; a second processing unit that receives the substrate carrying the liquid film and performs a predetermined process; and a transfer mechanism that transfers the substrate between the first processing unit and the second processing unit. In order to achieve the above object, the liquid film is imaged at different times during the period from the formation of the liquid film to the transfer of the substrate into the second processing unit, and the operation of the transfer mechanism is controlled based on the differences between the plurality of captured images.

[0014] In the invention configured as described above, the liquid film on the surface of the substrate being transferred is imaged, and the operation of the transfer mechanism is controlled based on the differences between the images captured at different times. Therefore, changes in the state of the liquid film on the substrate surface can be detected and reflected in the transfer control. For example, the transfer speed can be suppressed to reduce vibration, or liquid can be replenished when the thickness of the liquid film decreases. As a result, the substrate can be stably transferred in a state where the surface of the substrate is covered with the liquid film, thereby preventing the exposure of the substrate surface.

[0015] Advantages of the Invention

[0016] As described above, according to the present invention, the liquid film on the surface of the substrate being transferred is imaged and its changes are reflected in the transfer control. Therefore, the substrate can be transferred in a state where the liquid film on the substrate surface is stable. As a result, exposure of the substrate surface due to vibration during transfer, evaporation of the liquid, etc. can be prevented.

[0017] The above and other objects and novel features of the present invention can be more fully understood by referring to the accompanying drawings and reading the following detailed description. However, the drawings are for illustrative purposes only and do not limit the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1A is a diagram showing a schematic configuration of an embodiment of the substrate processing apparatus of the present invention.

[0019] Figure 1BThis is a diagram showing the schematic structure of an embodiment of the substrate processing apparatus of the present invention.

[0020] Figure 2 This is a diagram showing the structure and installation environment of the central robot.

[0021] Figure 3A This is a diagram showing the substrate processing unit that performs wet processing.

[0022] Figure 3B This is a diagram showing the substrate processing unit that performs wet processing.

[0023] Figure 4 This is a diagram showing the substrate processing unit that performs supercritical drying processing.

[0024] Figure 5 This is a flowchart showing the operation of the substrate processing apparatus.

[0025] Figure 6 This is a flowchart showing the first method of transfer processing.

[0026] Figure 7 This is a flowchart showing the second method of transfer processing.

[0027] Figure 8 This is a flowchart showing the third method of transfer processing.

[0028] Figure 9 This is a flowchart showing the substrate processing operation including the transfer processing of the third method.

[0029] Figure 10 This is a flowchart showing the fourth method of transfer processing. Detailed Embodiment

[0030] Figure 1A and Figure 1B This is a diagram showing the schematic structure of an embodiment of the substrate processing apparatus of the present invention. More specifically, Figure 1A This is a plan view of the substrate processing apparatus 1 according to an embodiment of the present invention, Figure 1B This is a side view of the substrate processing apparatus 1. In addition, these diagrams do not show the appearance of the apparatus, but are schematic diagrams that easily show its internal structure by removing the outer wall panel and some other structures of the apparatus. The substrate processing apparatus 1 is, for example, an apparatus that is installed in a clean room and is used to perform a predetermined process on a substrate.

[0031] Here, as the "substrate" in the present embodiment, various substrates such as semiconductor substrates, glass substrates for photomasks, glass substrates for liquid crystal displays, glass substrates for plasma displays, substrates for FEDs (Field Emission Displays), substrates for optical discs, substrates for magnetic discs, and substrates for magneto-optical discs can be applied. Hereinafter, mainly taking a substrate processing apparatus for processing semiconductor substrates as an example, it will be described with reference to the accompanying drawings. However, it can also be similarly applied to the processing of various substrates exemplified above.

[0032] As Figure 1A shown, the substrate processing apparatus 1 includes a substrate processing unit 10 that performs processing on the substrate S, and an indexer unit 20 coupled to the substrate processing unit 10. The indexer unit 20 includes a container holding unit 21 and an indexer robot 22. The indexer unit 20 can hold a plurality of containers C for accommodating the substrate S. As the container C, a FOUP (Front Opening Unified Pod), an SMIF (Standard Mechanical Interface) box, an OC (Open Cassette), etc. that accommodate a plurality of substrates S in a sealed state can be used. The indexer robot 22 accesses the container C held by the container holding unit 21, takes out the unprocessed substrate S from the container C, or accommodates the processed substrate in the container C. In each container C, a plurality of substrates S are accommodated in a substantially horizontal posture.

[0033] The indexer robot 22 includes a base portion 221, a multi-joint arm 222, and a robot hand 223. The base portion 221 is fixed to the apparatus housing. The multi-joint arm 222 is arranged to be rotatable about a vertical axis relative to the base portion 221. At the front end of the multi-joint arm 222, the robot hand 223 is mounted. The robot hand 223 is configured to be able to place and hold the substrate S on its upper surface. Such an indexer robot having a multi-joint arm and a substrate holding robot hand is well-known, and thus detailed description thereof is omitted.

[0034] The substrate processing unit 10 includes: a central robot 15 that is arranged approximately at the center in a plan view; and a plurality of substrate processing units that are arranged to surround the central robot 15. Specifically, a plurality (4 in this example) of substrate processing units 11A, 12A, 13A, and 14A are arranged facing the space where the central robot 15 is arranged. These substrate processing units 11A to 14A respectively perform predetermined processing on the substrate S. When these processing units have the same function, parallel processing of a plurality of substrates can be performed. In addition, it can also be configured to combine processing units with different functions and sequentially perform different processing on one substrate.

[0035] As described later, the substrate processing apparatus 1 of the present embodiment is used for a series of processes of wet-processing a substrate S with a predetermined processing liquid and then drying the substrate S. For this purpose, two of the four substrate processing units, the substrate processing units 11A and 12A, are responsible for the wet-processing of the substrate S and have structures inside for enabling these processes. In addition, the other two substrate processing units 13A and 14A are responsible for the process of removing the residual liquid from the substrate S after the wet-processing and drying the substrate S (drying process), and have structures inside for enabling these processes.

[0036] In each of the substrate processing units 11A to 14A, a substrate processing main body that performs processing on the substrate S is housed in a processing chamber provided with a shutter that can be opened and closed on the side facing the central robot 15. That is, the substrate processing unit 11A has a processing chamber 110 and a shutter 111 provided on the side of the processing chamber 110 facing the central robot 15. The shutter 111 is provided to cover an opening (not shown) provided on the side of the processing chamber 110 facing the central robot 15. When the shutter 111 is opened, the opening is exposed, and the substrate S can be carried in and out through the opening. In addition, when processing the substrate S is performed in the processing chamber 110, the atmosphere inside the processing chamber 110 is blocked from the outside by closing the shutter 111.

[0037] Similarly, the substrate processing unit 12A has a processing chamber 120 and a shutter 121 provided on the side of the processing chamber 120 facing the central robot 15. In addition, the substrate processing unit 13A has a processing chamber 130 and a shutter 131 provided on the side of the processing chamber 130 facing the central robot 15. In addition, the substrate processing unit 14A has a processing chamber 140 and a shutter 141 provided on the side of the processing chamber 140 facing the central robot 15.

[0038] And, a set of substrate processing units arranged horizontally in this way is arranged in multiple stages (two stages in this example) in the vertical direction. That is, as Figure 1B shown, a substrate processing unit 11B is provided below the substrate processing unit 11A. The structure and function of the substrate processing unit 11B are the same as those of the substrate processing unit 11A. In addition, below the substrate processing unit 12A, a substrate processing unit 12B having the same structure and the same function as the substrate processing unit 12A is provided. Similarly, a substrate processing unit 13B is also provided below the substrate processing unit 13A ( Figure 2) In addition, a substrate processing unit (not shown) is also provided below the substrate processing unit 14A. Additionally, the number of stages of the substrate processing units is arbitrary and is not limited to the two examples shown here. Moreover, the number of substrate processing units arranged in each stage is not limited to the above description.

[0039] Figure 2 FIG. is a diagram showing the structure and installation environment of the central robot. The central robot 15 can receive the unprocessed substrate S from the indexer robot 22 and can transfer the processed substrate S to the indexer robot 22. More specifically, the central robot 15 includes a base portion 151, a lifting portion 152, a rotating portion 153, a telescopic arm 154, and a robot hand 155. The base portion 151 is fixed to the bottom frame of the substrate processing portion 10 and supports each structure of the central robot 15. The lifting portion 152 is mounted on the base portion 151, and the rotating portion 153 is mounted on the upper portion of the lifting portion 152. The lifting portion 152 is telescopically movable in the vertical direction, and the rotating portion 153 is lifted and lowered by this telescopic movement.

[0040] The rotating portion 153 can rotate about the vertical axis relative to the lifting portion 152. The base of the telescopic arm 154 is mounted on the rotating portion 153, and the robot hand 155 is mounted on the front end portion of the telescopic arm 154. The telescopic arm 154 telescopes within a predetermined range in the horizontal direction. The robot hand 155 can place and hold the substrate S on its upper surface and can transfer the substrate S to and from the robot hand 223 of the indexer robot 22. The structure of such a robot hand is well known, and thus a detailed description thereof is omitted.

[0041] The telescopic arm 154 telescopes in the horizontal direction, thereby enabling the substrate S held by the robot hand 155 to move in the horizontal direction. In addition, the rotating portion 153 rotates relative to the lifting portion 152, thereby enabling the direction of the horizontal movement of the substrate S to be specified. Further, the lifting portion 152 raises and lowers the rotating portion 153, thereby enabling the height of the substrate S, that is, the vertical position, to be adjusted.

[0042] A support member 156 extending upward is mounted on the rotating portion 153. The support member 156 is mounted on the side of the rotating portion 153 on the side opposite to the extending direction of the telescopic arm 154 so as not to interfere with the horizontal movement of the robot hand 155. A CCD camera 157 is mounted on the upper end of the support member 156. The optical axis direction of the CCD camera 157 is slightly downward from the horizontal direction, and the substrate S held by the robot hand 155 is viewed from an oblique upper direction so as to fall within the shooting field of view. Thereby, the upper surface of the substrate S can be photographed. The photographed data is sent to the control unit 90.

[0043] In addition, a replenishing liquid nozzle 158 is provided in the rotating part 153. The replenishing liquid nozzle 158 opens downward above the substrate S held by the robot hand 155. The replenishing liquid nozzle 158 is connected to a low surface tension liquid supply part (not shown below), and supplies the low surface tension liquid supplied from the low surface tension liquid supply part to the substrate S as needed.

[0044] In the substrate processing apparatus 1 configured as described above, the processing of the substrate S is performed in the following manner. In the initial state, the unprocessed substrate S is stored in the container C placed on the container holding part 21. The indexer robot 22 takes out one unprocessed substrate S from the container C and transfers it to the center robot 15. The center robot 15 carries the received substrate S into the substrate processing unit where the processing for this substrate S is to be performed.

[0045] As Figure 2 shown, for example, when carrying the substrate S into the substrate processing unit 11A, the center robot 15 adjusts the height of the rotating part 153 through the lifting part 152, and positions the substrate S held by the robot hand 155 at the height of the baffle 111 on the side of the processing chamber 110 of the substrate processing unit 11A. The baffle 111 is opened, and the telescopic arm 154 extends toward the opening on the side of the processing chamber 110, thereby carrying the substrate S into the processing chamber 110. After the telescopic arm 154 retracts, the baffle 111 is closed, and the processing for the substrate S is performed in the processing chamber 110. The carrying of the substrate S into other substrate processing units can also be performed in the same manner.

[0046] On the other hand, when taking out the processed substrate S from the substrate processing unit 11A, the telescopic arm 154 enters the processing chamber 110 with the baffle 111 opened and takes out the processed substrate S. For the taken-out substrate S, it can either be carried into other substrate processing units to perform new processing, or be returned to the container C via the indexer robot 22. Hereafter, the specific processing sequence of this embodiment will be described in detail.

[0047] As Figure 2 shown, the center robot 15 is provided in a transfer space TS that is separated from the external space by the partition wall 101 on the side and above. The substrate processing unit 11A is installed on the side part of the partition wall 101 with the side surface of the processing chamber 110 provided with the baffle 111 facing the transfer space TS. The same applies to other substrate processing units.

[0048] In addition, in the substrate processing apparatus 1, a control unit 90 for controlling the operations of the respective parts of the apparatus is provided. The control unit 90 includes at least a CPU (Central Processing Unit) 91 and a memory 92. The CPU 91 causes the respective parts of the apparatus to perform predetermined operations by executing a control program prepared in advance. Further, the memory 92 stores the control program to be executed by the CPU 91, data generated by the execution, and the like. The operations related to the operations of the indexing robot 22 and the center robot 15, the opening and closing of the shutter in each processing chamber, and various processes for the substrate S are controlled by the CPU 91 that executes the control program.

[0049] Figure 3A and Figure 3B is a view showing a substrate processing unit that performs wet processing. More specifically, Figure 3A is a view showing the structure of the substrate processing unit 11A, Figure 3B is a view for explaining the operation of the substrate processing unit 11A. Here, the structure of the substrate processing unit 11A will be described, but the structures of other substrate processing units 11B, 12A, etc. that perform wet processing are substantially the same.

[0050] The substrate processing unit 11A includes a wet processing unit 30 as a substrate processing main body in a processing chamber 110. The wet processing unit 30 supplies a processing liquid to the upper surface of the substrate S to perform surface treatment, cleaning, etc. of the substrate S. Further, in order to prevent the upper surface of the substrate S carried out after wet processing from being exposed to the surrounding atmosphere, the wet processing unit 30 also performs a liquid film forming process of covering the upper surface of the substrate S after wet processing with a liquid film of a low surface tension liquid.

[0051] For this purpose, the wet processing unit 30 includes a substrate holding unit 31, a splash guard 32, a processing liquid supply unit 33, and a low surface tension liquid supply unit 34. Their operations are controlled by the control unit 90. The substrate holding unit 31 has a disk-shaped spin chuck 311 having a diameter substantially equal to that of the substrate S, and a plurality of chuck pins 312 are provided at the peripheral portion of the spin chuck 311. The chuck pins 312 abut against the peripheral portion of the substrate S to support the substrate S, whereby the spin chuck 311 can hold the substrate S in a horizontal posture in a state of being separated from the upper surface of the substrate S.

[0052] The rotary chuck 311 is supported in such a manner that its upper surface is horizontal by a rotary support shaft 313 extending downward from the central portion of its lower surface. The rotary support shaft 313 is rotatably supported by a rotation mechanism 314 mounted on the bottom of the processing chamber 110. The rotation mechanism 314 incorporates a rotation motor (not shown), and the rotation motor rotates according to a control instruction from the control unit 90. As a result, the rotary chuck 311 directly connected to the rotary support shaft 313 rotates about the vertical axis indicated by the single-dot chain line. Figure 3A and Figure 3B in, the vertical direction is the plumb direction. Thus, the substrate S rotates about the vertical axis while maintaining a horizontal posture.

[0053] The splash guard 32 is provided to surround the substrate holding portion 31 from the side. The splash guard 32 has a substantially cylindrical cup portion 321 provided to cover the peripheral portion of the rotary chuck 311 and a liquid receiving portion 322 provided below the outer peripheral portion of the cup portion 321. The cup portion 321 moves up and down according to a control instruction from the control unit 90. The cup portion 321 moves up and down between a lower position and an upper position. The lower position is such that Figure 3A shown, the upper end portion of the cup portion 321 descends to a position lower than the peripheral portion of the substrate S held by the rotary chuck 311, and the upper position is such that Figure 3B shown, the upper end portion of the cup portion 321 is located above the peripheral portion of the substrate S.

[0054] When the cup portion 321 is in the lower position, as Figure 3A shown, the substrate S held by the rotary chuck 311 is in a state of being exposed outside the cup portion 321. Therefore, it is possible to prevent, for example, the cup portion 321 from becoming an obstacle when loading and unloading the substrate S to and from the rotary chuck 311.

[0055] In addition, when the cup portion 321 is in the upper position, as Figure 3B shown, it surrounds the peripheral portion of the substrate S held by the rotary chuck 311. Thereby, it is possible to prevent the processing liquid splashed from the peripheral portion of the substrate S during liquid supply from scattering into the processing chamber 110, and the processing liquid can be reliably recovered. That is, the droplets of the processing liquid splashed from the peripheral portion of the substrate S due to the rotation of the substrate S adhere to the inner wall of the cup portion 321 and flow downward, and are collected and recovered by the liquid receiving portion 322 disposed below the cup portion 321. In order to recover a plurality of processing liquids individually, a plurality of cup portions may be provided concentrically.

[0056] The processing liquid supply unit 33 has the following structure: a rotating support shaft 332 is provided to be rotatable relative to a base 331 fixed to the processing chamber 110, and a nozzle 334 is mounted at the front end of an arm 333 horizontally extending from the rotating support shaft 332. The rotating support shaft 332 rotates according to a control instruction from the control unit 90, whereby the arm 333 swings. Thus, the nozzle 334 at the front end of the arm 333 is in such a state asFigure 3A moves between a retracted position that retracts laterally from above the substrate S and a processing position above the substrate S as shown in Figure 3B the figure.

[0057] The nozzle 334 is connected to a processing liquid supply source (not shown) provided in the control unit 90. When an appropriate processing liquid is sent out from the processing liquid supply source, the processing liquid is ejected from the nozzle 334 onto the substrate S. As shown in Figure 3B the figure, the rotary chuck 311 rotates the substrate S at a relatively low speed and the nozzle 33 positioned above the rotation center of the substrate S supplies the processing liquid Lq. Thereby, the upper surface Sa of the substrate S is processed with the processing liquid Lq. As the processing liquid Lq, liquids having various functions such as a developer, an etching liquid, a cleaning liquid, and a rinsing liquid can be used, and its composition is arbitrary. In addition, processing can also be performed by combining a plurality of processing liquids.

[0058] The low surface tension liquid supply unit 34 also has a structure corresponding to that of the processing liquid supply unit 33. That is, the low surface tension liquid supply unit 34 includes a base 341, a rotating support shaft 342, an arm 343, a nozzle 344, etc., and the structures of these are the same as the corresponding structures in the processing liquid supply unit 33. The rotating support shaft 342 rotates according to a control instruction from the control unit 90, whereby the arm 343 swings. The nozzle 344 at the front end of the arm 343 supplies a low surface tension liquid for forming a liquid film to the upper surface Sa of the substrate S after wet processing.

[0059] In the above Figure 3B description, the "processing liquid Lq", "arm 333", and "nozzle 334" are respectively renamed as "low surface tension liquid Lq", "arm 343", and "nozzle 344", thereby explaining the operation of the low surface tension liquid supply unit 34. Among them, the ejected liquid is a low surface tension liquid, which is a liquid of a different type from a general processing liquid.

[0060] When a fine concavo-convex pattern (hereinafter, simply referred to as "pattern") is formed on the upper surface Sa of the substrate to be processed, during the process of drying the wet substrate S after wet processing, sometimes pattern collapse occurs due to the surface tension of the liquid entering the pattern. As a method for preventing this, there are the following methods: a method of replacing the liquid in the pattern with a liquid having a lower surface tension and then drying; a sublimation drying method of covering the upper surface Sa of the substrate with a solid of a sublimable substance and sublimating the sublimable substance; and a supercritical drying method adopted in the present embodiment, etc.

[0061] For supercritical drying treatment that requires high temperature and high pressure states, an additional high-pressure chamber different from the chamber for wet treatment is needed. Therefore, it is necessary to transfer the substrate S after wet treatment to the high-pressure chamber. In order to avoid pattern collapse caused by the exposure of the substrate surface during transfer, it is preferable to cover the upper surface Sa of the substrate with a liquid or a solid. At this time, from the viewpoint of more surely preventing pattern collapse caused by surface tension, the liquid covering the upper surface Sa of the substrate is preferably a liquid having a surface tension smaller than that of the treatment liquid. In this specification, a liquid having such properties is referred to as a "low surface tension liquid".

[0062] In the present embodiment, transfer is performed in a state where the upper surface Sa of the substrate is covered with a liquid film of a low surface tension liquid. The liquid film is formed in the following manner. As Figure 3B shown, while the substrate S is rotating at a predetermined rotational speed, a low surface tension liquid Lq supplied from a low surface tension liquid supply unit (not shown) provided in the control unit 90 is ejected from the nozzle 344, whereby the upper surface Sa of the substrate is in a state of being covered with the liquid film LF of the low surface tension liquid. As the low surface tension liquid, a liquid having good miscibility with the treatment liquid used for wet treatment and having a surface tension smaller than that of the treatment liquid is preferable. For example, when the treatment liquid is mainly composed of water, isopropyl alcohol (IPA) is preferably used. In this way, the entire upper surface Sa of the substrate is in a state of being covered with the liquid film LF of the low surface tension liquid.

[0063] In addition, inside the processing chamber 110, above the substrate S held by the rotating chuck 311, a CCD camera 351 and an illumination light source 352 are arranged. The optical axis direction of the CCD camera 351 is slightly downward from the horizontal direction. Therefore, the CCD camera 351 looks down on the substrate S held by the rotating chuck 311 from an oblique upper direction so that it falls within the shooting field of view. The illumination light source 352 irradiates illumination light for shooting onto the substrate S. Thereby, the upper surface of the substrate S is photographed. The photographed data is sent to the control unit 90.

[0064] The substrate S carried out from the substrate processing unit 11A in a state where the upper surface Sa is covered with the liquid film LF is transferred to the substrate processing unit 13A and subjected to a drying treatment. That is, the substrate processing unit 13A has a function of performing a drying treatment as a substrate treatment, and this drying treatment is to remove the liquid film LF formed on the upper surface Sa of the substrate S carried in in a horizontal posture and to dry the substrate S. As the drying treatment, supercritical drying is applied in which the substrate S is covered with a supercritical fluid and then the supercritical fluid is vaporized (without passing through the liquid phase) to be removed. Here, the structure of the substrate processing unit 13A will be described, and the structures of other substrate processing units 13B, 14A, etc. that perform the drying treatment are basically the same.

[0065] Figure 4This is a diagram showing a substrate processing unit that performs supercritical drying processing. More specifically, Figure 4 This is a side cross-sectional view showing the internal structure of the substrate processing unit 13A. The principle of supercritical drying processing and the basic structure required therefor are well-known, and thus detailed explanations are omitted herein. The substrate processing unit 13A includes a high-pressure chamber 130, and a drying processing unit 40 that serves as the main body for performing drying processing is provided inside thereof. In the drying processing unit 40, a stage 41 for placing the substrate S is provided inside the high-pressure chamber 130. The stage 41 holds the substrate S whose upper surface Sa is covered with a liquid film by adsorption holding or mechanical holding. Since the high-pressure chamber 130 is at high pressure, components with a relatively simple internal structure and capable of withstanding high pressure are used for high-pressure resistance.

[0066] At the center of the lower surface of the stage 41, a rotating support shaft 42 extends downward. The rotating support shaft 42 is inserted through the bottom surface of the high-pressure chamber 130 via a high-pressure seal rotating introduction mechanism 43. The rotating shaft 431 of the high-pressure seal rotating introduction mechanism 43 is connected to a rotating mechanism 432. Therefore, if the rotating mechanism 432 operates according to a control command from the control unit 90, the substrate S rotates together with the stage 41 around a vertical rotation axis indicated by a single-dot chain line.

[0067] A fluid dispersion member 44 is provided inside the high-pressure chamber 130 and above the stage 41. The fluid dispersion member 44 is provided with a plurality of through-holes 442 that penetrate up and down with respect to a flat closing plate 441. Carbon dioxide gas is supplied to the upper part of the high-pressure chamber 130 from a carbon dioxide supply unit 45 as needed, and the carbon dioxide gas is rectified by the fluid dispersion member 44 and uniformly supplied to the substrate S from above the substrate S.

[0068] In addition, nitrogen is introduced into the high-pressure chamber 130 from a nitrogen supply unit 46 as needed. As needed, nitrogen is supplied in various ways, that is, as a gas at normal temperature or after heating, or as liquefied liquid nitrogen after cooling, for purposes such as purging the gas inside the high-pressure chamber 130 or cooling the inside of the chamber.

[0069] Moreover, the high-pressure chamber 130 is connected to a discharge mechanism 48. The discharge mechanism 48 has a function of discharging various fluids such as gas and liquid introduced into the high-pressure chamber 130. The discharge mechanism 48 includes pipes, valves, pumps, etc. for this purpose. Thus, the fluid inside the high-pressure chamber 130 can be quickly discharged when necessary.

[0070] Although not shown in the figure, the control unit 90 has a structure for detecting the pressure and temperature inside the high-pressure chamber 130 and a structure for controlling these to predetermined values. That is, the control unit 90 has a function of controlling the pressure and temperature inside the high-pressure chamber 130 to predetermined target values.

[0071] Next, the operation of the substrate processing apparatus 1 configured as described above will be described. As described previously, this substrate processing apparatus 1 is an apparatus that sequentially performs wet processing and drying processing on a substrate S. The main flow of this processing is as follows. That is, after the substrate S is transported to the substrate processing unit that performs wet processing and the processing based on the processing liquid is performed, a liquid film of a low surface tension liquid is formed, and then the substrate S is transported to the substrate processing unit that performs drying processing to remove the liquid film and dry the substrate S. Hereinafter, the specific processing contents will be described.

[0072] Here, it is assumed that the substrate processing unit 11A performs wet processing on one substrate S, and the substrate processing unit 13A performs drying processing on this one substrate S for description. However, the combination of the substrate processing unit that performs wet processing and the substrate processing unit that performs drying processing is arbitrary and is not limited thereto. In addition, in the following description, in order to clearly show the functions of the respective substrate processing units, the substrate processing units 11A etc. that perform wet processing are respectively referred to as "wet processing units", and in addition, the substrate processing units 13A etc. that perform drying processing are referred to as "drying processing units".

[0073] Figure 5 This is a flowchart showing the operation of this substrate processing apparatus. This operation is realized by the CPU 91 executing a control program prepared in advance to cause each part of the apparatus to perform a predetermined operation. First, the indexer robot 22 takes out one unprocessed substrate S from one container C that stores unprocessed substrates (step S101). Then, the substrate S is transferred from the indexer robot 22 to the center robot 15 (step S102). The center robot 15 transports the substrate S into the substrate processing unit (wet processing unit) 11A that performs wet processing (step S103).

[0074] The substrate processing unit 11A into which the substrate S has been transported performs wet processing on the substrate S (step S104). As described previously, the content of the wet processing is to supply the processing liquid to the substrate S and perform processing for machining and cleaning the upper surface Sa of the substrate. For the substrate S after wet processing, a liquid film forming process for forming a liquid film LF of a low surface tension liquid is performed (step S105).

[0075] The substrate S having the liquid film LF formed on the upper surface Sa through the liquid film forming process is taken out from the substrate processing unit 11A by the center robot 15 and transported into the substrate processing unit (drying processing unit) 13A that performs drying processing. That is, a transfer process of transferring the substrate S from the substrate processing unit 11A to the substrate processing unit 13A is performed (step S106). Various methods are considered for the transfer process, and these will be described later.

[0076] The substrate processing unit 13A with the substrate S is moved in, and a drying process (step S107) is performed on the substrate S to remove the attached liquid and dry the substrate S. In the substrate processing unit 13A, a supercritical drying process using a supercritical fluid is performed. That is, carbon dioxide is introduced into the high-pressure chamber 130 from the carbon dioxide supply unit 45, and the pressure in the chamber is sufficiently increased, whereby the carbon dioxide is liquefied. Alternatively, liquid carbon dioxide may be introduced into the high-pressure chamber 130. The liquid carbon dioxide covers the upper surface Sa of the substrate. The liquefied carbon dioxide sufficiently dissolves the organic solvent. Therefore, the liquid such as IPA remaining in the pattern is replaced by the liquid carbon dioxide.

[0077] Next, the temperature and pressure in the high-pressure chamber 130 are adjusted to conditions under which carbon dioxide is in a supercritical state. Thereby, the carbon dioxide in the high-pressure chamber 130 becomes a supercritical fluid. The fluid in the supercritical state has extremely high fluidity and extremely low surface tension. In particular, the supercritical fluid generated from carbon dioxide sufficiently dissolves organic solvents such as IPA and acetone. Therefore, the supercritical fluid of carbon dioxide enters the deep part of the fine pattern and removes the remaining organic solvent components from within the pattern. From the point of becoming a supercritical state at a relatively low pressure and low temperature, this is also one of the reasons for applying carbon dioxide to the supercritical drying process.

[0078] Then, the pressure in the high-pressure chamber 130 is rapidly reduced, whereby the supercritical fluid directly vaporizes without passing through the liquid phase and is removed from the substrate S. Thereby, the substrate S becomes a state in which the liquid components are completely removed and dried. The liquid components remaining in the pattern are replaced by the supercritical fluid, and the supercritical fluid directly vaporizes, thereby avoiding the problem of pattern collapse caused by the surface tension of the liquid in the pattern.

[0079] The processed substrate S is taken out from the substrate processing unit 13A by the central robot 15 (step S108). The taken-out processed substrate S is transferred from the central robot 15 to the indexer robot 22 (step S109). The indexer robot 22 stores the substrate S in a container C (step S110). The container C for storing the processed substrate S may be the container that stored the substrate S in the unprocessed state, or may be another container.

[0080] And, when there is a substrate to be processed ( "Yes" in step S111), return to step S101 and perform the above processing on the next substrate S. If there is no substrate to be processed ( "No" in step S111), the processing is terminated.

[0081] The process for processing one substrate S has been described above. However, in an actual apparatus, processing of multiple substrates is performed in parallel. That is, while one substrate S is being processed in one substrate processing unit, at least one of the conveyance of other substrates by the indexer robot 22 and the center robot 15 and the substrate processing by other substrate processing units can be performed simultaneously in parallel.

[0082] More specifically, for example, after transferring the substrate S from the indexer robot 22 to the center robot 15 in step S102, the indexer robot 22 can access the container C again and take out other substrates. Further, for example, after loading one substrate S into the substrate processing unit 11A in step S103, the center robot 15 can load other substrates into other substrate processing units or unload other substrates that have been processed by other substrate processing units.

[0083] Therefore, in the case where multiple substrates S need to be processed sequentially, by appropriately adjusting the operation sequence of each part of the apparatus for processing each substrate S, the processing of multiple substrates is performed in parallel. In this way, the throughput of the processing as the entire substrate processing apparatus 1 can be increased. The specific operation sequence needs to be appropriately determined according to the processing specifications, the time required for each of the above steps, and whether simultaneous processing is possible.

[0084] Next, several modes of the transfer process ( Figure 5 step S106) of the above substrate processing will be described. The purpose of the transfer process is to unload the substrate S having the liquid film LF formed on the upper surface Sa from the substrate processing unit 11A and transfer it to the substrate processing unit 13A while maintaining the state of the liquid film LF, that is, without exposing the upper surface Sa of the substrate. For this purpose, in the present embodiment, images taken by the CCD camera 351 provided in the substrate processing unit 11A and the CCD camera 157 provided in the center robot 15 are used.

[0085] Figure 6 is a flowchart showing the first mode of the transfer process. First, in the processing chamber 110 of the substrate processing unit 11A, the substrate S immediately after the liquid film formation process is photographed by the CCD camera 351 (step S201). At this time, actually, the liquid film LF formed covering the upper surface Sa of the substrate is photographed. Preferably, the entire liquid film LF covering the upper surface Sa of the substrate falls within the image. The data of the photographed image is stored as reference data in the memory 92 of the control unit 90.

[0086] Next, the manipulator 155 of the central robot 15 enters the processing chamber 110 and holds the substrate S (step S202), and starts to transfer the substrate S by horizontally moving the manipulator 155 (step S203). During the transfer, the liquid film LF on the upper surface Sa of the substrate is photographed at any time by the CCD camera 157 provided on the central robot 15 (step S204). Between the image photographed by the CCD camera 157 and the image photographed by the CCD camera 351, it is preferable that the position, size, and elevation angle of the substrate S in the image are the same.

[0087] The image obtained by photographing is compared with the reference image photographed initially. That is, the difference between the newly photographed image by the CCD camera 157 and the image photographed by the CCD camera 351 in the processing chamber 110 is obtained (step S205). As a result, if there is a significant difference between the two images, it is considered that there is some change in the liquid film LF on the substrate S. For example, the absolute value of the difference of each pixel between the two images is accumulated in the image, and it is determined whether there is a significant difference based on whether this value exceeds a preset reference amount (threshold value). The difference in the liquid film thickness is manifested as a change in the surface reflectivity and a difference in the generation state of interference fringes. This difference can be detected by obtaining the difference of the images.

[0088] As the possible changes in the liquid film during the transfer, it is considered that there are mainly the shaking of the liquid surface accompanied by vibration, and the reduction of the liquid volume due to liquid dropping or volatilization. In response to these, it is effective to supplement the low surface tension liquid to the substrate S. Therefore, when there is a significant change in the liquid film ( "Yes" in step S206), a predetermined amount of the low surface tension liquid is supplemented from the replenishing liquid nozzle 158 provided on the central robot 15 (step S207). Thereby, it is possible to prevent the liquid film from breaking due to the reduction of the liquid volume. When no significant change is seen ( "No" in step S206), no liquid replenishment is performed.

[0089] Before the substrate S reaches the target position, that is, inside the high-pressure chamber 130 of the substrate processing unit 13A, the above steps S204 to S207 are repeatedly executed ( "No" in step S208). Therefore, during the transfer of the substrate S, the state of the liquid film LF is always monitored, and the low surface tension liquid is supplemented when necessary. Thereby, the liquid film on the substrate S is stably maintained. If the target position is reached ( "Yes" in step S208), the substrate S is transferred from the central robot 15 to the platform 41 inside the high-pressure chamber 130 (step S209), thereby completing the transfer of the substrate S.

[0090] Figure 7This is a flowchart showing the second method of transfer processing. In this method, step S221 is provided instead of step S207 in the first method. The processing contents other than this are the same as those in the first method, so the same symbols are used for the same processing and the description is omitted. In step S221 executed in the second method instead of the liquid replenishment in the first method, the transfer speed of the center robot 15 for the substrate S is changed.

[0091] For example, in a case where a low surface tension liquid drops from the substrate S due to vibration or rapid acceleration / deceleration, the liquid drop can be suppressed by transferring the substrate S more slowly. That is, in this case, it is only necessary to reduce the transfer speed. For example, in a case where the surface of the liquid film is rippled, it can be considered that the liquid film LF shakes due to vibration. On the other hand, the decrease in the liquid volume due to liquid volatilization is manifested as a decrease in the film thickness of the liquid film on the entire substrate S. In this case, it is preferable to increase the transfer speed to complete the transfer in a shorter time. In addition, in the case of implementing this method alone, the replenishing liquid nozzle 158 can also be omitted.

[0092] Figure 8 This is a flowchart showing the third method of transfer processing. In addition, Figure 9 This is a flowchart showing the substrate processing operation including this transfer processing. In this method, since the content of the transfer processing is different, the operation of the substrate processing itself also needs to be changed. Here, the same symbols are used for the processing with the same content as the previously described processing and the description is omitted. As Figure 8 shown, in the transfer processing of the third method, when there is a significant change in the image of the liquid film in step S206, an exception flag for making the subsequent processing different is set (step S231). In this case, the transfer of the substrate S is interrupted.

[0093] As Figure 9 shown, in the substrate processing of this method, a step S121 for determining whether the exception flag is set is added after the transfer processing (step S106). When the flag is set (\"Yes\" in step S121), the center robot 15 returns the substrate S to the wet processing unit 11A (step S122). Subsequently, the exception flag is reset (step S123). Then, after the liquid film forming process (step S105) is executed again in the wet processing unit 11A, the transfer processing (step S106) is executed again.

[0094] In this method, when there is a change in the liquid film LF on the substrate S, the liquid film LF is reformed in the substrate processing unit 11A. If no exception flag is set ("No" in step S121), the liquid film LF does not change significantly, so the drying process (step S107) is continued. Thus, it is possible to avoid transporting the substrate S into the substrate processing unit 13A in a state where the liquid film LF is damaged. That is, the substrate S can be transferred while stably maintaining the state of the liquid film LF. In addition, in this method, the supplementary liquid nozzle 158 can also be omitted when implemented alone.

[0095] Figure 10 It is a flowchart showing the fourth method of the transfer process. Figure 10 In, for the same content as the transfer process shown in Figure 6 the same symbols are marked and the description is omitted. In this method, when the liquid film is photographed by the CCD camera 351 in step S201, the image is compared with a pre-prepared ideal image. That is, the difference between the photographed image and the ideal image is obtained (step S241). The ideal image is an image corresponding to the ideal state in which the upper surface Sa of the substrate S is uniformly covered with a liquid film LF of a predetermined thickness.

[0096] This process is used to verify whether an appropriate liquid film LF is formed on the substrate S. That is, for the substrate S after wet processing, due to surface unevenness and changes in wettability as a result of the processing, it is difficult to form a uniform liquid film. Especially when the surface of the processed substrate is in a liquid-repellent state, it is difficult to support a uniform liquid film. In addition, due to abnormal operation of the device structure for forming the liquid film and the holding method of the substrate S, there may be a situation where an appropriate liquid film is not formed initially. By comparing the image of the substrate S immediately after the liquid film is formed with the ideal image, such an abnormality can be detected immediately. In addition, the liquid supply amount for liquid film formation and the rotation speed of the substrate S can also be adjusted based on the magnitude of the difference from the ideal image.

[0097] If there is a significant difference between the photographed image and the ideal image ("Yes" in step S242), the transfer process is aborted after appropriate error handling (step S243). The content of the error handling is arbitrary. For example, it is considered to notify the operator of the occurrence of an abnormality and display and output the image at this time. Preferably, even if the process for the substrate S where an abnormality is detected is aborted, the process for the substrate without an abnormality can continue.

[0098] If no abnormality is detected ("No" in step S242), the photographed image is used as a reference image and the transfer process after step S202 is executed. Here, it is assumed that the transfer process of the first method is executed, but the process of the second or third method can also be executed.

[0099] In addition, the processes of the above-described various methods may be appropriately combined. For example, multiple reference amounts may be set for the magnitude of the difference between the image captured by the CCD camera 157 and the reference image, and subsequent processing may be varied according to the magnitude of the difference.

[0100] In actual substrate processing, depending on subsequent processing conditions and the like, there are cases where, from the time when the substrate S is placed in the processing chamber 110 and a liquid film LF is formed on its upper surface Sa until the substrate S starts to be transported, it is necessary to standby for a long time. As a measure to cope with this situation, for example, the processing shown may be locally changed and implemented in the following manner. During a plurality of different times from when the liquid film LF is formed on the substrate S until the start of transportation, the liquid film LF is captured by the CCD camera 351 in the processing chamber 110. These images are compared, and when it is confirmed that there is a significant difference in the liquid film between the latest captured image and the ideal image or the initially captured image, liquid replenishment or appropriate error processing is performed (step S243). Figure 10 In this way, in the substrate processing of the present embodiment, a plurality of images of the liquid film captured at different times during the period from when the liquid film LF is formed on the substrate S until the end of transportation are compared, and subsequent transportation actions are determined based on the results. Therefore, it is possible to detect without delay changes in the liquid film caused by vibration or volatilization during transportation, and change the transportation action according to the situation. In this way, in the present embodiment, the substrate can be transported in a state where the liquid film is stably formed on the surface. As a result, it is possible to prevent the exposure of the substrate surface caused by vibration or liquid volatilization during transportation.

[0101] As described above, in the above-described embodiment, the wet processing unit, i.e., the substrate processing unit 11A, etc., functions as the "first processing unit" of the present invention, and the drying processing unit, i.e., the substrate processing unit 13A, etc., functions as the "second processing unit" of the present invention. Moreover, the central robot 15 functions as the "transport mechanism" of the present invention. In addition, the processing chamber 110 functions as the "processing chamber" of the present invention.

[0102] As described above, in the above-described embodiment, the robot arm 155 functions as the "holding member" of the present invention. And the CCD cameras 157 and 351 function as the "second camera" and the "first camera" of the present invention respectively, and they constitute the "imaging unit" of the present invention. In addition, the replenishing liquid nozzle 158 functions as the "liquid supply mechanism" of the present invention. In addition, the control unit 90 functions as the "control unit" of the present invention. And the image of the liquid film captured by the camera 351 immediately after the liquid film is formed corresponds to the "pre-transportation image" in the present invention.

[0103] In addition, in the above-described embodiment, the end effector 155 functions as the "holding member" of the present invention. And the CCD cameras 157 and 351 function as the "second camera" and the "first camera" of the present invention respectively, and they constitute the "imaging unit" of the present invention. In addition, the replenishing liquid nozzle 158 functions as the "liquid supply mechanism" of the present invention. In addition, the control unit 90 functions as the "control unit" of the present invention. And the image of the liquid film captured by the camera 351 immediately after the liquid film is formed corresponds to the "pre-transportation image" in the present invention.

[0104] In addition, the present invention is not limited to the above-described embodiments, and various modifications other than the above can be made within the scope not departing from the gist thereof. For example, in the above-described embodiment, the substrate processing units 11A, 13A, and the central robot 15 corresponding to the "first processing unit", "second processing unit", and "transfer mechanism" of the present invention are respectively housed in one housing to form an integrated processing system. However, the present invention can also be applied to a processing system having a first processing unit and a second processing unit provided independently of each other, and a transfer mechanism for transferring a substrate between them.

[0105] In addition, in the above-described embodiment, the image of the liquid film captured by the CCD camera 351 in the processing chamber 110 is used as the reference image, but the reference image is not limited thereto. For example, the image captured by the CCD camera 157 at the initial stage of transfer may be used as the reference image. In this case, the CCD camera 351 in the processing chamber 110 is not required for the purpose of observing the state of the liquid film during transfer. In addition, particularly when the CCD camera 157 is configured to move integrally with the robot hand 155, the positional relationship between the substrate S held by the robot hand 155 and the CCD camera 157 remains unchanged at each stage during transfer. According to this configuration, mutual positional alignment is not required in the comparison between images, and in addition, the accuracy of differential calculation can be further improved.

[0106] In addition, in the above-described embodiment, the CCD camera 157 is attached to the central robot 15 that moves together with the substrate S when transferring the substrate S. Instead of these, for example, the substrate S being transferred is photographed by a camera fixedly provided at a position overlooking the transfer path of the substrate S. Particularly in the case of a substrate S provided with a fine pattern, in order to prevent pattern collapse, the substrate surface is not allowed to be exposed even for a short time. Therefore, at this time, a state is preferably such that a plurality of cameras are arranged on the transfer path and the liquid film transferred together with the substrate S is photographed at short time intervals. Alternatively, a mechanism for causing the camera to follow the movement of the substrate S may be provided.

[0107] In addition, a structure for catching and recovering the liquid that has fallen from the substrate S being transferred may be provided in the central robot 15.

[0108] As described above, as illustrated in the specific embodiments, the present invention can be configured as follows. For example, the first processing unit forms a liquid film on a substrate in a processing chamber, and the photographing unit has a first camera provided in the processing chamber. According to this structure, the liquid film immediately after formation can be photographed, and for example, the state of the subsequent liquid film can be evaluated based on the liquid film included in the image.

[0109] In addition, for example, the transfer mechanism may also include a holding member for holding the substrate, and the imaging unit may also include a second camera disposed on the transfer mechanism and moving together with the holding member. With this configuration, imaging can be performed at any time during transfer, enabling the detection of changes in the liquid film on the substrate without delay and taking necessary countermeasures.

[0110] In addition, for example, between the case where the difference calculated from a plurality of images exceeds a preset reference amount and the case where it does not exceed the preset reference amount, the control unit can make the time taken for transfer from the first processing unit to the second processing unit different. As causes of changes in the liquid film, there are vibrations or sudden acceleration / deceleration during transfer, volatilization of the liquid component, etc. Sometimes, changes in the liquid film can be suppressed by changing the transfer speed.

[0111] In addition, for example, the transfer mechanism includes a liquid supply mechanism for supplying liquid to the transferred substrate, and the control unit may be configured such that if the difference calculated from a plurality of images exceeds a preset reference amount, the liquid supply mechanism supplies liquid to the substrate. With this configuration, the liquid constituting the liquid film is replenished as needed, enabling continuous transfer while maintaining the liquid film on the substrate. Especially when the liquid film is composed of a material with high volatility, the reduction in the thickness of the liquid film due to volatilization during transfer may cause the surface of the substrate to be exposed. By providing a mechanism for replenishing liquid in the transfer unit, this problem can be eliminated.

[0112] In addition, for example, the control unit may also be configured such that if the difference calculated from a plurality of images exceeds a preset reference amount, the transfer mechanism returns the substrate to the first processing unit and the first processing unit reforms the liquid film. With this configuration, the liquid film is reformed in the first processing unit having the structure required for forming the liquid film. Therefore, even without separately providing a structure for replenishing liquid during transfer, breakage of the liquid film during transfer can be prevented.

[0113] In addition, for example, if the liquid constituting the liquid film is an organic solvent, the second processing unit may also perform supercritical drying treatment on the substrate. Supercritical drying treatment requires a dedicated high-pressure environment for implementation under high pressure. In addition, components resistant to high pressure are required. Therefore, in reality, it is carried out in a place different from the wet processing that can be performed at normal pressure. In this case, transfer of the substrate after wet processing is required, and by applying the present invention, transfer can be performed without exposing the surface of the substrate. From the viewpoint of affinity with the supercritical fluid, it is preferable to use an organic solvent in the formation of the liquid film, but organic solvents with high volatility are likely to be lost during transfer. By observing the state of the liquid film by applying the present invention, it is also possible to surely cover the surface of the substrate with the liquid film and perform transfer in such cases.

[0114] In addition, for example, a plurality of images may also include pre-transfer images taken before the transfer mechanism starts to transfer the substrate. With this structure, it is possible to determine whether the surface of the substrate is appropriately covered with a liquid film at the start time of transfer, and necessary measures can be taken according to the situation. For example, the control unit can determine whether to start the transfer of the substrate by the transfer mechanism based on the difference between the ideal image corresponding to the substrate in the state where the liquid film is ideally loaded and the pre-transfer image. In this way, it is possible to avoid transferring the substrate in a state where the surface is not appropriately covered with the liquid film.

[0115] Industrial Applicability

[0116] The present invention can be applied to the entire substrate processing technology for transferring a substrate between processing units that perform different processes while covering the surface of the substrate with a liquid film. For example, it is suitable for the process of drying a substrate after wet processing by supercritical drying.

[0117] As described above, the invention has been described according to a predetermined embodiment, but this description is not intended to be construed in a limiting sense. By referring to the description of the invention, various modifications of the disclosed embodiment will be apparent to those skilled in the art, similar to other embodiments of the present invention. Therefore, it is considered that the scope of the claimed invention includes such modifications or embodiments without departing from the true scope of the invention.

[0118] Reference Signs

[0119] 1 Substrate processing apparatus

[0120] 11A Wet processing unit, substrate processing unit (first processing unit)

[0121] 13A Drying processing unit, substrate processing unit (second processing unit)

[0122] 15 Central robot (transfer mechanism)

[0123] 90 Control unit (control section)

[0124] 110 Processing chamber (chamber)

[0125] 130 High-pressure chamber

[0126] 155 Manipulator (holding member)

[0127] 157 CCD camera (imaging section, second camera)

[0128] 351 CCD camera (imaging section, first camera)

[0129] 158 Supplementary liquid nozzle (liquid supply mechanism)

[0130] LF liquid film

[0131] S substrate.

Claims

1. A substrate processing apparatus, characterized in that, it comprises: a first processing unit that supplies a liquid to a substrate and covers the surface of the substrate with a liquid film; a transfer mechanism that transfers the substrate carrying the liquid film; a second processing unit that receives the substrate transferred by the transfer mechanism and performs a predetermined process; an imaging unit that images the liquid film formed on the surface of the substrate; and a control unit that controls the operation of the transfer mechanism based on differences between a plurality of images respectively captured by the imaging unit at different times during a period from the formation of the liquid film until the substrate is transferred into the second processing unit by the transfer mechanism, wherein the difference is a cumulative value of absolute values of differences of each pixel between two images, and the control unit makes the time taken from the first processing unit to the second processing unit different in cases where the difference exceeds a preset reference amount and in cases where the difference does not exceed the preset reference amount.

2. The substrate processing apparatus according to claim 1, characterized in that, the first processing unit forms the liquid film on the substrate in a processing chamber, and the imaging unit has a first camera disposed in the processing chamber.

3. The substrate processing apparatus according to claim 1, characterized in that, the liquid is an organic solvent, and the second processing unit performs supercritical drying processing on the substrate.

4. A transfer control method for a substrate processing apparatus, the substrate processing apparatus having: a first processing unit that supplies a liquid to a substrate and covers the surface of the substrate with a liquid film; a second processing unit that receives the substrate carrying the liquid film and performs a predetermined process; and a transfer mechanism that transfers the substrate between the first processing unit and the second processing unit, characterized in that, the liquid film is imaged at different times during a period from the formation of the liquid film until the substrate is transferred into the second processing unit, and the operation of the transfer mechanism is controlled based on differences between the captured plurality of images, wherein the difference is obtained as a cumulative value of absolute values of differences of each pixel between two images, and the time taken from the first processing unit to the second processing unit is made different in cases where the difference exceeds a preset reference amount and in cases where the difference does not exceed the preset reference amount.

Images