JP2024034960A - Substrate drying equipment, substrate processing equipment, and substrate drying method - Google Patents

Abstract

The present invention provides a substrate drying device, a substrate processing device, and a substrate drying method that can reduce the occurrence of watermarks on a substrate.
A drying device (substrate drying device) 300 includes a support section 32 for receiving a substrate W carried into a drying chamber 31, a drive mechanism 33 for rotating the substrate W supported by the support section 32, and a rotating substrate. A supply unit 34 that supplies a processing liquid onto the processing surface of the substrate W, a shielding plate 35 having an opposing surface 35a facing the processing surface of the substrate W, and the shielding plate 35 are moved in the direction toward and away from the substrate W. an air supply unit 37 that removes oxygen in the atmosphere on the surface to be processed of the substrate W by supplying oxygen-free gas to the space between the opposing surface 35a and the substrate W; A measuring section 38 that measures the film thickness of the processing liquid supplied onto the surface to be processed of the substrate W, and a counter surface 35a and a surface to be processed that are suitable for the film thickness measured by the measuring section 38 and a preset film thickness. It has an adjustment unit 42 that adjusts the gap based on information indicating the distance (gap) to the surface.
[Selection diagram] Figure 3

Description

The present invention relates to a substrate drying apparatus, a substrate processing apparatus, and a substrate drying method.

In the manufacturing process of manufacturing semiconductors, liquid crystal panels, etc., substrate processing involves supplying a processing liquid to the surface to be processed of a substrate such as a wafer or liquid crystal substrate, processing the surface to be processed, and cleaning and drying the surface after processing. A device is used.

In the drying process of this substrate processing apparatus, patterns around memory cells and gates may collapse and become clogged due to the spacing and structure of the patterns, the surface tension of the processing liquid, and the like. In particular, pattern collapse is more likely to occur because the aspect ratio, which is the ratio of depth to wiring width and opening width, has increased in recent years as semiconductors have become smaller due to higher integration and higher capacitance. There is.

In order to suppress such pattern collapse, a substrate drying method has been proposed in which after rinsing with a rinsing liquid such as DIW (ultra-pure water), IPA (2-propanol: isopropyl alcohol) is used as the rinsing liquid. This substrate drying method replaces DIW (ultra-pure water) on the surface of the substrate with IPA, and then dries the substrate by shaking off the IPA from the substrate using centrifugal force generated by high-speed rotation of the substrate. . Since IPA has a lower surface tension than DIW, it is possible to reduce the possibility of pattern collapse due to surface tension when separating from the substrate surface.

In such a drying process, if an atmosphere containing pure water and oxygen exists in the space above the surface to be processed of the substrate, the pure water, oxygen, and The silicon on the surface to be processed of the substrate reacts and a watermark is generated. This is caused by three reactions: pure water, oxygen, and silicon; therefore, if oxygen can be removed from the atmosphere on the surface of the substrate to be processed, the occurrence of watermarks can be suppressed.

Therefore, by placing a circular shielding plate of the same size or slightly larger than the substrate close to the substrate and supplying nitrogen gas between the substrate and the shielding plate, the oxygen atmosphere between the substrate and the shielding plate is exhausted. It is being done. At this time, IPA is supplied to the substrate from a nozzle located at the center of the shielding plate. When the supply of IPA is finished, the substrate is rotated at high speed to shake off the IPA on the surface to be processed of the substrate, thereby drying the substrate.

Japanese Patent Application Publication No. 8-316190

As described above, the shielding plate is placed close to the substrate so that the distance (gap) between the shielding plate and the substrate is narrowed. However, if the rotational speed (number of rotations per unit time) of the substrate is low, the liquid film of the processing liquid supplied from the nozzle of the shielding plate onto the processing surface of the substrate becomes thicker. The above processing liquid may adhere to the surface of the shielding plate that faces the substrate (opposed surface). Furthermore, the treatment liquid may adhere to the opposing surface due to shaking or splashing.

Then, even if the processing liquid on the surface to be processed of the substrate is dried by shaking it off by rotating the substrate, the processing liquid that has adhered to the opposing surface of the shielding plate will re-adhere to the substrate. The processing liquid that has redeposited in this way causes watermarks. To deal with this, if the gap is widened by separating the shielding plate from the substrate, the space will become wider, and even with the supply of nitrogen gas, oxygen will not be able to be sufficiently exhausted, resulting in watermarks. However, it has been difficult to adjust the position of the shielding plate relative to the substrate so that it is suitable for discharging oxygen and at a distance that does not cause adhesion of processing liquid.

An object of the embodiments of the present invention is to provide a substrate drying apparatus, a substrate processing apparatus, and a substrate drying method that can reduce the occurrence of watermarks on a substrate.

A substrate drying apparatus according to an embodiment of the present invention includes a drying chamber into which a substrate is carried, a support section that receives the substrate carried into the drying chamber, and a drive mechanism that rotates the substrate supported by the support section. , a supply unit for supplying a processing liquid onto the processing surface of the rotating substrate, a shielding plate having an opposing surface facing the processing surface, and moving the shielding plate in a direction toward and away from the substrate. an air supply unit that removes oxygen in the atmosphere on the surface to be processed by supplying oxygen-free gas to a space between the opposing surface and the substrate; a measurement unit that measures the film thickness of the processing liquid supplied above, the film thickness measured by the measurement unit, and the opposing surface and the processing surface that are suitable for the film thickness set in advance; and an adjustment section that adjusts the distance based on information indicating the distance.

A substrate processing apparatus according to an embodiment of the present invention includes a processing apparatus that processes the substrate by supplying a substrate processing liquid while rotating the substrate, and a processing apparatus that processes the substrate by supplying a substrate processing liquid while rotating the substrate that has been processed by the processing apparatus. a substrate drying device according to any one of claims 1 to 4; and a substrate drying device according to any one of claims 1 to 4, wherein a liquid film is formed by the cleaning liquid supplied by the cleaning device, and and a transport device for transporting the substrate in the same state and transporting it into the substrate drying device.

A substrate drying method according to an embodiment of the present invention includes a processing liquid supply step in which a supply section supplies a processing liquid onto a processing surface of a substrate rotating in a drying chamber, and a measurement section supplies the processing liquid onto the processing surface. a film thickness measuring step of measuring the film thickness of the processing liquid; an approaching step of moving a shielding plate having an opposing surface facing the surface to be processed in a direction in which a moving mechanism approaches the substrate; and an air supply section. includes an air supply step of eliminating oxygen in the atmosphere on the surface to be processed by supplying an oxygen-free gas to the space between the opposing surface and the substrate; an adjustment step in which an adjustment unit adjusts the distance based on the film thickness and information indicating a distance between the opposing surface and the treated surface suitable for the film thickness that has been set in advance; and a drying step of discharging the substrate by centrifugal force caused by rotation of the substrate.

Embodiments of the present invention can provide a substrate drying apparatus, a substrate processing apparatus, and a substrate drying method that can reduce the occurrence of watermarks on a substrate.

FIG. 1 is a simplified configuration diagram showing a substrate processing apparatus according to an embodiment. 2 is a configuration diagram showing a cleaning device and a drying device of the substrate processing apparatus in FIG. 1. FIG. 3 is an internal configuration diagram showing the drying device of FIG. 2. FIG. FIG. 3 is an explanatory diagram showing the relationship between film thickness and gap. It is a graph showing the relationship between film thickness, gap, and number of watermarks. FIG. 3 is an internal configuration diagram showing the drying device when the substrate is carried in (A) and when the first volatile solvent is supplied (B). FIG. 6 is an internal configuration diagram showing the drying device at the time of supplying the second water-repellent solvent, at the time of film thickness measurement (A), and at the time of gap adjustment (B). FIG. 3 is an internal configuration diagram showing the drying device when drying a substrate. It is a flowchart which shows the procedure of a substrate drying process of an embodiment. It is an internal block diagram which shows the modification of the 2nd volatile solvent supply part.

Embodiments of the present invention will be described below with reference to the drawings.
[overview]
As shown in FIG. 1, the substrate processing apparatus 1 of this embodiment includes a plurality of chambers 1a that house devices for performing various types of processing, and a plurality of substrates are stored in a cassette (FOUP) 1b and transported in a pre-process. This is a single-wafer processing apparatus in which one substrate W is processed in each chamber 1a. Unprocessed substrates W are taken out one by one by the transfer robot 1c from the cassette 1b, and after being temporarily placed on the buffer unit 1d, the unprocessed substrates W are transferred to each chamber 1a and processed by various devices described below. It will be done.

The substrate processing apparatus 1 includes a processing apparatus 110, a cleaning apparatus 120, a transport apparatus 200, a drying apparatus 300, and a control apparatus 400. For example, the processing apparatus 110 applies a substrate processing liquid (for example, a phosphoric acid aqueous solution, a mixture of hydrofluoric acid and nitric acid, a mixture of acetic acid, sulfuric acid, and hydrogen peroxide (SPM)) to the rotating substrate W. This is an etching device that removes unnecessary films and leaves a circuit pattern by supplying a film (e.g.). The cleaning device 120 cleans the substrate W that has been etched by the etching device using a cleaning liquid C (see FIG. 2). The transport device 200 transports the substrate W between the buffer unit 1d and each chamber 1a, and between each chamber 1a. For example, the transport device 200 transports the substrate W processed in the processing device 110 to the cleaning device 120, and transports the substrate W cleaned in the cleaning device 120 to the drying device 300. The drying device (substrate drying device) 300 performs a drying process by removing the cleaning liquid C using centrifugal force while rotating the substrate W that has been cleaned with the cleaning liquid C. Control device 400 controls each of the above devices.

Note that the substrate W processed according to this embodiment is, for example, a semiconductor wafer. Hereinafter, the surface of the substrate W on which the pattern etc. are formed will be referred to as the surface to be processed. As the cleaning liquid C (see FIG. 2) for the cleaning process in the cleaning device 120, an alkaline cleaning liquid (APM) and ultrapure water (DIW) are used. APM is a chemical mixture of aqueous ammonia and hydrogen peroxide, and is used to remove residual organic matter. DIW is used to wash away the substrate processing liquid remaining on the surface of the substrate W to be processed after the substrate W has been processed with the substrate processing liquid. Further, DIW is used to wash away APM remaining on the surface of the substrate W to be processed after the APM processing. After cleaning with the cleaning liquid C, the drying device 300 uses a volatile solvent as the treatment liquid. First, in the drying device 300, in order to replace the cleaning liquid C, a first volatile solvent (IPA) is used as a processing liquid. Since IPA has a lower surface tension than DIW and higher volatility, IPA is used to replace DIW and reduce pattern collapse due to surface tension.

Furthermore, in this embodiment, a second volatile solvent is used as the treatment liquid. The second volatile solvent is a solvent that has a lower surface tension when vaporized than the first volatile solvent. Further, the vaporization temperature of the second volatile solvent is higher than that of the first volatile solvent. As such a second volatile solvent, PGMEA (propylene glycol monoethyl acetate) can be used. Further, the second volatile solvent used includes a water repellent agent. The water repellent agent replaces the hydroxyl group (-OH) on the surface to be treated of the substrate W with a functional group (for example, -CH ₃ , C ₂ H ₅ ) to form a water repellent film (Si-O-R (R : It is a modifier that can form a functional group)). For example, HMDS (hexamethyldisilazane), which is a silane coupling agent, can be used as the water repellent agent. In the following explanation, the second volatile solvent is supplied in such a manner that the second volatile solvent containing a water repellent agent is supplied.

The reason for using PGMEA containing HMDS is that HMDS easily reacts with moisture. That is, when HMDS reacts with moisture in the air, it loses its water-repellent effect on the surface to be processed of the substrate W. Therefore, by mixing HMDS with PGMEA, it can be supplied to the substrate W while preventing it from reacting with moisture in the air. In addition, in the following description, if the first volatile solvent and the second volatile solvent are not distinguished, they will simply be referred to as a treatment liquid.

[Cleaning device]
As shown in FIG. 2, the cleaning device 120 includes a cleaning chamber 11 which is a container in which a cleaning process is performed, a support section 12 that supports a substrate W, a rotation mechanism 13 that rotates the support section 12, and a rotation mechanism 13 that rotates the support section 12. It has a cup 14 that receives from the periphery of W, and a supply section 15 that supplies cleaning liquid C. The supply unit 15 is provided with a nozzle 15a for dropping the cleaning liquid C and a moving mechanism 15b for moving the nozzle 15a.

The cleaning process is performed by supplying the cleaning liquid C from the nozzle 15a to the processing surface of the substrate W, which is supported by the support part 12 and rotated by the rotation mechanism 13. The cleaning process is performed by supplying APM to the surface to be processed of the substrate W that has been subjected to the etching process in the processing apparatus 110 to perform APM cleaning, and after the APM cleaning, by performing a pure water rinsing process using DIW, the surface to be processed of the substrate W is cleaned. Wash away remaining APM with pure water. As a result, the surface to be processed of the substrate W is filled with the DIW cleaning liquid C. The cleaning chamber 11 is provided with an opening 11a through which substrates W are carried in and out, and the opening 11a is configured to be openable and closable by a door 11b.

[Transport device]
The transport device 200 has a handling device 20. The handling device 20 includes a robot hand 21 that grips the substrate W and a moving mechanism 22. The robot hand 21 grips the substrate W. The moving mechanism 22 moves the robot hand 21. The transport device 200 transports the substrate W between the buffer unit 1d and various devices, and between the various devices. For example, the substrate W that has undergone the etching process is carried out from the processing apparatus 110 and carried into the cleaning apparatus 120 with a liquid film of cleaning liquid (DIW) C formed on the surface of the substrate W to be processed. The moving mechanism 22 also moves the robot hand 21 to carry out the cleaned substrate W from the cleaning device 120, and forms a liquid film of the cleaning liquid (DIW) C on the surface of the substrate W to be processed. In this state, it is carried into the drying device 300. Note that the purpose of transporting the substrate W with a liquid film of cleaning liquid (DIW) C formed on the processing surface of the substrate W is to prevent particles from adhering to the processing surface of the substrate W during transport. This is to do so.

[Drying device]
As shown in FIGS. 2 and 3, the drying device 300 includes a drying chamber 31, a support section 32, a drive mechanism 33, a supply section 34 (a first volatile solvent supply section 341, a second volatile solvent supply section 342 ), a shielding plate 35, a moving mechanism 36, an air supply section 37, a measuring section 38, and a cup 39. The substrate W is carried into the drying chamber 31 . The drying chamber 31 is a chamber 1a for drying the substrate W therein. The drying chamber 31 has a box shape such as a rectangular parallelepiped or a cube, for example. The inner wall of the drying chamber 31 is coated with silica to improve dust resistance. The drying chamber 31 is provided with an opening 31a through which the substrate W is carried in and out. The opening 31a is provided so that it can be opened and closed by a door 31b. Such a drying chamber 31 includes a supply section 34 (a first volatile solvent supply section 341, a second volatile solvent supply section 342), a shielding plate 35, a moving mechanism 36, an air supply section 37, and a measurement section, which will be described later. A portion 38 and a cup 39 are housed therein.

Further, the drying chamber 31 is provided with an inlet 31c and an exhaust port 31d. An air supply section 31e that includes piping, a valve, and an air supply device that supplies clean gas ( _N2, etc.) is connected to the introduction port 31c. An exhaust section 31f including piping, a valve, and an exhaust device for exhausting gas is connected to the exhaust port 31d. By supplying clean gas into the drying chamber 31 from the inlet 31c, a normal atmosphere can be created in the drying chamber 31. Further, by creating a configuration in which gas is supplied into the drying chamber 31 through the inlet 31c and gas within the drying chamber 31 is discharged through the exhaust port 31d, a flow of gas within the drying chamber 31 is created.

The support portion 32 supports the substrate W. The support section 32 includes a rotating table 32a, a plurality of holding members 32b, and a rotating shaft 32c. The rotary table 32a has a cylindrical shape with a diameter larger than that of the substrate W, and is a disk with a flat top surface. The plurality of holding members 32b are arranged at equal intervals along the outer circumference of the substrate W, and hold the substrate W in a horizontal state with a space between them and the upper surface of the rotary table 32a. The plurality of holding members 32b are provided movably between a closed position in contact with the edge of the substrate W and an open position away from the edge of the substrate W by an opening/closing mechanism (not shown). The rotating shaft 32c is a vertical axis that supports the rotating table 32a from below and serves as the center of rotation.

The drive mechanism 33 is a mechanism that rotates the substrate W supported by the support section 32. The drive mechanism 33 has a drive source such as a motor, and rotates the support portion 32 via a rotating shaft 32c.

The supply unit 34 supplies a processing liquid onto the processing surface of the rotating substrate W. As shown in FIG. 3, the supply section 34 includes a first volatile solvent supply section 341 and a second volatile solvent supply section 342. The first volatile solvent supply section 341 supplies the first volatile solvent V onto the processing surface of the substrate W that is carried into the drying chamber 31 and supported by the support section 32 . The first volatile solvent supply section 341 has a nozzle 341a. The nozzle 341a supplies the first volatile solvent V toward the vicinity of the center of the surface to be processed of the substrate W. IPA, which is the first volatile solvent V, is supplied to the nozzle 341a from a storage section 341b outside the drying chamber 31 via a pipe (not shown) (see FIG. 6(B)). The nozzle 341a is arranged along the central axis of the shielding plate 35, which will be described later, and is provided so as to be movable together with the shielding plate 35.

In the cleaning process in the cleaning device 120, the DIW cleaning liquid C is finally deposited on the surface of the substrate W to be processed by a pure water rinsing process using DIW after alkaline cleaning using APM. IPA is supplied to the substrate W carried from the cleaning device 120 to the drying device 300 in this liquid state, thereby replacing DIW with IPA.

The second volatile solvent supply unit 342 supplies PGMEA (solvent containing HMDS), which is the second volatile solvent H, to the IPA that has replaced the DIW on the surface to be processed of the substrate W (FIG. 7(A) )reference). The second volatile solvent supply section 342 includes a nozzle 342a, a swing arm 342b, and a swing mechanism 342c. The nozzle 342a supplies the second volatile solvent H toward the vicinity of the center of the surface to be processed of the substrate W. PGMEA is supplied to the nozzle 342a from a storage section outside the drying chamber 31 via piping (none of which is shown).

By supplying the second volatile solvent H containing a water repellent agent, a water repellent film is formed on the surface to be treated of the substrate W, so that the surface to be treated of the substrate W is repelled from hydrophilic silanol groups. By lowering the interfacial energy on the surface to be processed of the substrate W by replacing it with an aqueous methyl group, the first volatile solvent V can be floated and the removal of the liquid on the surface to be processed of the substrate W can be promoted. Note that water repellency here refers to the property of repelling liquid, that is, liquid repellency, and is not limited to the property of repelling water.

The swing arm 342b is provided with a nozzle 342a at its tip, and can be moved between a supply position where the nozzle 342a faces near the center of the surface to be processed of the substrate W on the support part 32, and a position where the nozzle 342a is evacuated from the supply position to carry in the substrate W. or move it to an evacuation position where it can be carried out. The swing mechanism 342c is a mechanism that swings the swing arm 342b.

The shielding plate 35 is a plate that faces the processed surface of the substrate W and has a larger diameter than the substrate W. The shielding plate 35 is circular, and its lower surface is a flat facing surface 35a facing the substrate W. The opposing surface 35a is arranged parallel to the rotary table 32a, and faces the substrate W supported by the support section 32 in parallel. An opening 35b for supplying the first volatile solvent V and purge gas is formed at the center of the opposing surface 35a.

Furthermore, a support 35c is provided on the upper surface of the shielding plate 35 and extends upward from a position including the center thereof. A ventilation passage 35d is provided inside the support body 35c, extending downward along the central axis and communicating with the opening 35b. The upper part of the ventilation path 35d communicates with a connection port 35e extending on the side surface of the support body 35c.

Furthermore, a nozzle 341a of the first volatile solvent supply section 341 is inserted into the ventilation path 35d along the central axis. Since the lower end of the nozzle 341a reaches the opening 35b and is directed toward the center of the substrate W, the first volatile solvent V can be supplied toward the vicinity of the center of the surface to be processed of the substrate W.

The moving mechanism 36 is a mechanism that moves the shielding plate 35 in a direction toward and away from the substrate W. The moving mechanism 36 moves the shielding plate 35 between a standby position and a supply position. The standby position is a position at a height where the shielding plate 35 does not obstruct loading/unloading of the substrate W (see FIG. 6(A)). Further, the supply position is lower than the standby position and is at a height at which supply of the processing liquid to the substrate W is started (see FIG. 6(B)). As the moving mechanism 36, for example, there are various types that move the shielding plate 35 in a direction parallel to the rotation axis 32c of the rotary table 32a, such as a cylinder that raises and lowers an arm to which the support body 35c of the shielding plate 35 is attached, and a ball screw mechanism. However, the details are omitted.

The air supply unit 37 supplies oxygen-free gas to the space between the opposing surface 35a and the substrate W, thereby eliminating oxygen in the atmosphere above the surface to be processed of the substrate W. The air supply section 37 includes an air supply device 37a that supplies this gas (hereinafter referred to as purge gas), and is connected to a connection port 35e via a pipe having a valve (not shown). As the purge gas, an inert gas such as N ₂ is used. By bringing the shielding plate 35 close to the substrate W, a narrow space is formed between the opposing surface 35a of the shielding plate 35 and the surface of the substrate W to be processed. By supplying the purge gas from the air supply section 37, the purge gas is blown out from the opening 35b to the vicinity of the center of the substrate W through the ventilation path 35d, thereby eliminating oxygen in this narrow space. That is, as a result, oxygen present on the surface to be processed of the substrate W is eliminated.

The measurement unit 38 measures the film thickness of the processing liquid supplied onto the processing surface of the substrate W supported by the support unit 32 . The measuring section 38 is provided on the shielding plate 35. Further, the measuring section 38 is provided so as to be able to measure a plurality of locations of the processing liquid. More specifically, the measuring section 38 includes a detecting section 38a. As the detection unit 38a, for example, a laser displacement meter, a camera, or the like is used. A plurality of detection parts 38a are arranged along the radial direction from the center of the shielding plate 35 toward the outer circumference. For example, the detection parts 38a are embedded in three holes 35f formed at a position near the central axis in the radial direction, a position near the outer periphery, and an intermediate position so that the lower end opens on the opposing surface 35a of the shielding plate 35. It is. The detection surface of the detection unit 38a faces the substrate W from the opening of the hole 35f.

As the film thickness measurement method by the measurement unit 38, for example, an optical interference principle can be used. In addition, as another example, it is possible to use a weight scale within the support part 32. When using this weighing scale, the weight of the liquid film on the surface of the substrate W to be processed (the weight of the liquid film = the weight of the substrate including the liquid film - the weight of the substrate) can be determined theoretically or experimentally. Convert to thickness.

The cup 39 is formed into a cylindrical shape so as to surround the support portion 32 (see FIG. 2). The upper part of the peripheral wall of the cup 39 is inclined radially inward and is open so that the substrate W on the support part 32 is exposed. The cup 39 receives the cleaning liquid C scattered from the rotating substrate W and flows it downward. A discharge port (not shown) is formed at the bottom of the cup 39 to discharge the cleaning liquid C flowing down. Note that the cup 39 is connected to the drive mechanism 33 and is provided so as to be movable up and down together with the support section 32.

[Control device]
The control device 400 is a computer that controls each part of the substrate processing apparatus 1. The control device 400 includes a processor that executes programs, a memory that stores various information such as programs and operating conditions, and a drive circuit that drives each element. Note that the control device 400 includes an input device for inputting information and a display device for displaying information.

The control device 400 controls the processing device 110, the cleaning device 120, the transport device 200, and the drying device 300. For example, while rotating the substrate W supported by the support section 32, the control device 400 supplies the first volatile solvent V from the first volatile solvent supply section 341 to the first liquid film of the cleaning liquid C. The first volatile solvent V supplied onto the processing surface of the substrate W by supplying the second volatile solvent H from the second volatile solvent supply section 342, After being replaced with the second volatile solvent H, the liquid film of the second volatile solvent H is discharged by centrifugal force caused by the rotation of the substrate W. Note that, as described later, the control device 400 adjusts the distance between the opposing surface 35a and the surface of the processing liquid according to the film thickness of the processing liquid measured by the measurement unit 38.

Such a control device 400 includes a mechanism control section 41, an adjustment section 42, and a storage section 43. The mechanism control section 41 controls the mechanisms of each section. For example, the mechanism control unit 41 controls the rotation speed, rotation start timing, and rotation stop timing of the support unit 32 by controlling the drive mechanism 33 . Furthermore, the mechanism control unit 41 measures the film thickness of the detection unit 38a and controls the operation of the movement mechanism 36 to change the height of the shielding plate 35 and adjust the distance between the opposing surface 35a and the surface of the processing liquid. do. Furthermore, the mechanism control unit 41 controls the discharge of the first volatile solvent V by the first volatile solvent supply unit 341, the swinging of the nozzle 342a by the second volatile solvent supply unit 342, and the control of the second volatile solvent It controls operations such as discharging H and supplying purge gas by the air supply section 37.

The adjustment unit 42 adjusts the film thickness of the processing liquid measured by the measurement unit 38 (hereinafter simply referred to as film thickness) and the distance between the opposing surface 35a and the processed surface of the substrate W that is suitable for the preset film thickness. (hereinafter referred to as a gap), the gap is adjusted based on information indicating the gap. That is, the adjustment unit 42 adjusts the distance between the facing surface 35a and the surface to be processed of the substrate W suitable for the film thickness of the processing liquid by moving the shielding plate 35 up and down using the moving mechanism 36. Basically, if the gap is too narrow, the processing liquid on the substrate W will come into contact with the opposing surface 35a. As a result, when the substrate W is dried, the processing liquid adhering to the opposing surface 35a falls and remains on the surface to be processed. When the remaining processing liquid dries, it appears as a water mark. Such watermarks are caused by droplets adhering randomly on the surface to be processed, and thus appear in scattered spots. On the other hand, if the gap is too wide, oxygen will easily enter the nitrogen atmosphere between the opposing surface 35a and the surface to be processed. As a result, watermarks caused by the reaction of silicon and water on the surface to be treated with oxygen increase.

The inventors have focused on the fact that there is an optimal value for the gap that prevents the treatment liquid from adhering to the opposing surface 35a, depending on the film thickness of the treatment liquid. In other words, the inventor found that there is a correlation between the gap and film thickness and the number of watermarks, and that there is a gap in which the number of watermarks is less than the allowable value for the film thickness. Ta. As a simple example, as shown in FIG. 4(A), when the film thickness of the processing liquid L is thick, the gap G is increased, and as shown in FIG. 4(B), when the film thickness is thin, the gap G is increased. will make the gap G smaller.

However, the film thickness of the processing liquid L is not always the same for each substrate W, and varies depending on the type and temperature of the processing liquid L, the rotational speed of the substrate W, the undulations of the surface of the liquid film, and the like. Therefore, the ease with which the processing liquid adheres to the opposing surface 35a also differs depending on these conditions. Therefore, it is preferable to determine in advance through experiments a gap at which the watermark is less than an allowable value with respect to the film thickness. The storage unit 43 stores information indicating the relationship between the film thickness and the gap. That is, information indicating the distance between the facing surface 35a and the surface to be processed that is suitable for the film thickness is set in advance.

FIG. 5 shows the relationship between film thickness, gap, and number of watermarks. Note that the number of watermarks here refers to the number of watermarks formed on the substrate W, not on the opposing surface 35a. When the film thickness is a few μm, the smaller the gap is about 3 mm (for example, 2 to 5 mm), the fewer the number of watermarks will be. If the gap is larger than 10 mm, it becomes difficult to maintain an N ₂ atmosphere between the opposing surface 35a and the surface to be processed, so the number of watermarks tends to gradually increase. Therefore, when the film thickness is several μm, the preferable range of the gap between the shielding plate 35 and the substrate W is 3 to 10 mm. More preferably, if the maximum value of the measured film thickness is 10 μm or less, a gap of about 3 mm is maintained. For example, if the maximum film thickness is 10 μm, the gap is set to 3 mm.

On the other hand, when the film thickness is several mm thick and the gap is as small as about 3 mm (for example, 2 to 5 mm), the number of watermarks increases. This is because the liquid film on the surface of the substrate W to be processed comes into contact with the shielding plate 35, thereby contaminating the substrate W. Furthermore, if the gap is larger than 20 mm, it becomes difficult to maintain an N ₂ atmosphere between the opposing surface 35a and the surface to be processed, so the number of watermarks increases. Therefore, when the film thickness is several mm, the preferable range of the gap between the shielding plate 35 and the substrate W is 7 to 20 mm. More preferably, if the measured film thickness is 1 mm or more, a gap of about 5 mm is maintained. For example, if the maximum film thickness is 3 mm, the gap is set to 8 mm. As described above, as the film thickness increases, the risk of liquid splashing onto the shielding plate 35 increases, so the gap needs to be widened.

Furthermore, while the processing liquid is being supplied onto the surface to be processed of the substrate W and the shielding plate 35 is close to the substrate W, the gap adjustment can be performed in real time while constantly measuring the film thickness of the processing liquid. In this case, the height of the shielding plate 35 is adjusted in the same way as above, depending on whether the measured film thickness is thick or thin so that an optimum gap can be maintained at all times. In this way, by linking the measurement of the film thickness and the raising and lowering of the shielding plate 35, the processing liquid adheres to the opposing surface 35a while maintaining the N ₂ atmosphere between the opposing surface 35a and the surface to be processed. This can reduce the

Furthermore, the adjustment unit 42 adjusts the gap based on the maximum film thickness among the film thicknesses measured at the plurality of locations by the measurement unit 38 . When the type of processing liquid is changed, when the rotational speed of the substrate W changes, and the processing liquid waves, the film thickness differs depending on the location on the surface of the substrate W to be processed. Among these, since adhesion to the opposing surface 35a is likely to occur at the thickest point, by adjusting the gap based on this point, changes in film thickness can be detected early and adhesion of the processing liquid can be reduced.

[motion]
The operation of the substrate processing apparatus 1 of this embodiment as described above will be explained with reference to the explanatory diagrams of FIGS. 6 to 8 and the flowchart of FIG. 9, in addition to the above-mentioned FIGS. 1 to 5. Note that a substrate manufacturing method in which the substrate W is manufactured by processing the substrate W according to the following procedure, and a substrate drying method in which the substrate W is dried are also aspects of this embodiment.

First, as shown in FIG. 2, the substrate W after being etched in the processing apparatus 110 is carried into the cleaning apparatus 120 by the transport apparatus 200. In the cleaning apparatus 120, while the support part 12 holding the substrate W rotates, the supply part 15 supplies APM to the rotation center of the surface to be processed of the substrate W to perform alkali rinsing treatment, and then supplies DIW. Perform rinsing with pure water. After cleaning, the transport device 200 transports the substrate W coated with the cleaning liquid C, which is DIW, from the cleaning device 120 and transports it into the drying device 300 .

As shown in FIG. 6A, the substrate W carried in from the opening 31a of the drying chamber 31 of the drying apparatus 300 is placed on the support section 32 with a liquid film (DIW) of the cleaning liquid C formed on the surface to be processed. is held by the holding member 32b (step S01). As shown in FIG. 6B, the drive mechanism 33 rotates the substrate W together with the support section 32, and the air supply section 37 discharges the purge gas from the opening 37b of the opposing surface 35a (step S02). ). Then, the shielding plate 35 descends from the standby position to the processing liquid supply position (step S03), and the first volatile solvent supply unit 341 supplies the first volatile solvent to the rotation center of the surface to be processed of the substrate W. IPA of V is supplied (step S04).

As a result, centrifugal force due to the rotation of the substrate W causes IPA to spread over the entire surface of the substrate W to be processed, and alcohol rinsing processing is performed in which DIW that has been deposited on the surface of the substrate W to be processed is replaced with IPA. . Note that here, since IPA, which has a lower surface tension than DIW, is substituted, the surface tension that acts between patterns formed on the surface to be processed of the substrate W is reduced.

Then, as shown in FIG. 7A, while the drive mechanism 33 rotates the substrate W together with the support section 32, the shielding plate 35 rises to the standby position, and the second volatile solvent supply section 342 swings. As the arm 342b swings, the nozzle 342a moves above the rotation center of the surface to be processed of the substrate W, and the nozzle 342a supplies PGMEA, which is the second volatile solvent H, to the rotation center (step S05 ). As a result, the centrifugal force caused by the rotation of the substrate W causes the PGMEA to spread over the entire surface of the substrate W to be processed, and the HMDS contained in PGMEA binds to the surface to be processed of the substrate W to form a water-repellent film. be done. In other words, the first volatile solvent V present on the surface to be processed of the substrate W is replaced by PGMEA, which is the second volatile solvent H, and HMDS contained in PGMEA converts the hydroxyl groups on the surface to be processed into functional groups. A water-repellent film is formed by replacing with .

Furthermore, as shown in FIG. 7B, the swinging arm 342b retracts the nozzle 342a from above the substrate W, and while the shielding plate 35 approaches the substrate W, the first volatile solvent supply section 341 , IPA, which is the first volatile solvent V, is supplied to the rotation center of the surface to be processed of the substrate W (step S06). HMDS contained in PGMEA generates particles when it reacts with moisture in the atmosphere. Therefore, if the second volatile solvent H remains, particles will remain on the surface of the substrate W to be processed. Therefore, in this embodiment, after supplying the second volatile solvent H, the first volatile solvent V is supplied again onto the surface to be processed of the substrate W to wash away the second volatile solvent H. . At the same time, the detection unit 38a of the measurement unit 38 starts measuring the film thickness on the surface to be processed of the substrate W (step S07).

The adjustment unit 42 refers to the film thickness and gap information stored in the storage unit 43 and controls the moving mechanism 36 via the mechanism control unit 41 so that the gap is optimal based on the measured film thickness. It is operated to adjust the gap between the opposing surface 35a of the shielding plate 35 and the substrate W (step S08). That is, the gap is adjusted so that the processing liquid does not adhere to the shielding plate 35 while the processing liquid is being supplied. At this time, since the air supply unit 37 supplies purge gas between the opposing surface 35a and the substrate W, oxygen is exhausted from the atmosphere in the gap.

Then, as shown in FIG. 8, while rotating the substrate W, a drying process is performed in which the liquid film of the first volatile solvent V is shaken off by centrifugal force until a predetermined time period has elapsed (NO in step S09). . Also during this time, the measurement section 38 measures the film thickness (step S07), and the adjustment section 42 adjusts the gap (step S08).

In this way, by forming a water-repellent film using the second volatile solvent H, it is possible to reduce collapse of the pattern and dry the substrate W. That is, as described above, the water-repellent agent that has penetrated into the IPA liquid film forms a water-repellent film between the patterns, reducing the lyophilicity and increasing the contact angle of the liquid. As a result, the surface tension of the liquid on the surface of the substrate W is further reduced, so that the force of attraction between the patterns can be weakened, and pattern collapse can be suppressed. Further, since the purge gas eliminates oxygen between the opposing surface 35a of the shielding plate 35 and the substrate W, it is possible to prevent watermarks from forming due to reaction with oxygen.

After a predetermined period of time has elapsed (YES in step S09), the drive mechanism 33 stops rotating the substrate W together with the support section 32 (step S10), the shielding plate 35 rises (step S11), and the transport device 200 moves the substrate W. is carried out from the opening 31a (step S12).

[effect]
(1) The drying apparatus (substrate drying apparatus) 300 of this embodiment as described above includes a drying chamber 31 into which a substrate W is carried, a support section 32 that receives the substrate W carried into the drying chamber 31, and a support section. A drive mechanism 33 that rotates the substrate W supported by the substrate W; a supply unit 34 that supplies a processing liquid onto the processing surface of the rotating substrate W; A shielding plate 35 having a large-diameter opposing surface 35a, a moving mechanism 36 that moves the shielding plate 35 in a direction toward and away from the substrate W, and a gas that does not contain oxygen in the space between the opposing surface 35a and the substrate W. an air supply section 37 which removes oxygen in the atmosphere on the surface to be processed of the substrate W by supplying the same; and a measurement section 38 which measures the film thickness of the processing liquid supplied onto the surface to be processed of the substrate W. , an adjustment unit 42 that adjusts the gap based on the film thickness measured by the measurement unit 38 and information indicating the distance (gap) between the facing surface 35a and the surface to be processed that is suitable for the preset film thickness. have

More specifically, the adjustment unit 42 adjusts the gap between the facing surface 35a and the surface to be processed of the substrate W suitable for a preset film thickness of the processing liquid by moving the shielding plate 35 up and down using the moving mechanism 36. adjust.

The substrate processing apparatus 1 of this embodiment includes a processing apparatus 110 that processes a substrate W by supplying a substrate processing liquid while rotating the substrate W, and a processing apparatus 110 that processes a substrate W by supplying a substrate processing liquid while rotating the processed substrate W. The substrate W cleaned in the cleaning device 120 is carried out with a liquid film formed by the cleaning liquid C supplied by the cleaning device 120, and is carried into the drying device 300. A conveying device 200 is provided.

The substrate drying method of the present embodiment includes a processing liquid supply step in which the supply unit 34 supplies a processing liquid onto the processing surface of the substrate W rotating in the drying chamber 31, and a measurement unit 38 in which A film thickness measuring step of measuring the film thickness of the processing liquid supplied onto the surface, and a movement mechanism 36 for moving the shielding plate 35, which faces the surface to be processed of the substrate W and has an opposing surface 35a having a diameter larger than that of the substrate W. is moved in a direction approaching the substrate W, and the air supply unit 37 supplies a purge gas that does not contain oxygen to the space between the opposing surface 35a and the substrate W. information indicating the air supply process to eliminate oxygen in the atmosphere, the film thickness measured by the measurement unit 38, and the distance (gap) between the opposing surface 35a and the surface to be processed that is suitable for the preset film thickness. Based on this, the process includes an adjustment process in which the adjustment unit 42 adjusts the gap, and a drying process in which the processing liquid is discharged by centrifugal force caused by rotation of the substrate W.

In this way, since the distance between the opposing surface 35a and the processing liquid surface is adjusted according to the film thickness of the processing liquid, oxygen by the purge gas can be eliminated and the adhesion of the processing liquid to the opposing surface 35a can be prevented. In the process of drying the substrate W, it is possible to prevent the occurrence of water marks due to dropping of the processing liquid from the opposing surface 35a. In other words, when the processing liquid adheres to the facing surface 35a, while the liquid film on the surface to be processed is being removed, the processing liquid falls from the facing surface 35a and adheres to the surface being dried. However, only the adhered portion remains and eventually forms a watermark due to natural drying. However, in this embodiment, the processing liquid does not adhere to the shielding plate 35 from the time when the processing liquid is supplied while the shielding plate 35 is close to the substrate W until the processing liquid is shaken off and dried. It is possible to prevent water marks from occurring due to falling processing liquid.

(2) The measuring section 38 is provided on the shielding plate 35. Therefore, when the processing liquid is being supplied onto the surface to be processed of the substrate W and the shielding plate 35 is in close proximity to the substrate W, the distance from the opposing surface 35a to the measurement target is always accurately measured, and in real time. Since the film thickness can be detected, the gap can be adjusted according to changes in the film thickness to reduce adhesion of the processing liquid.

(3) The measurement unit 38 is provided so as to be able to measure multiple locations of the processing liquid. Therefore, even if there are variations in film thickness within the plane of the substrate W, an optimal gap can be determined based on the measurement results at a plurality of locations.

(4) The adjustment unit 42 adjusts the gap based on the maximum film thickness among the film thicknesses at the plurality of locations. Therefore, since the gap is adjusted based on the film thickness at which the processing liquid is most likely to adhere to the opposing surface 35a, the gap can be adjusted to a value that prevents the processing liquid from adhering.

(5) In the processing liquid supply step, a liquid film is formed by the cleaning liquid C, and while the substrate W supported by the support section 32 is rotated by the drive mechanism 33, the first volatile solvent supply section 341 supplies the first volatile solvent. A water repellent film is formed from a first volatile solvent supply step in which a liquid film of cleaning liquid C is replaced with a first volatile solvent V by supplying a volatile solvent V, and a second volatile solvent supply section 342. By supplying the second volatile solvent H, which contains a water repellent agent and has a surface tension lower than that of the first volatile solvent V when vaporized, the liquid film of the first volatile solvent V is transferred to the second volatile solvent H. The method includes a water repellent film forming step of replacing the volatile solvent H with a water repellent film and forming a water repellent film on the substrate W.

Therefore, when the shielding plate 35 is close to the substrate W, the film thickness can be constantly measured in real time during replacement when fluctuations are likely to occur in the processing liquid, and the gap can be adjusted to follow film thickness fluctuations. , it is possible to more reliably reduce adhesion of the processing liquid to the opposing surface 35a.

(Modified example)
(1) The measuring unit 38 may have a configuration in which the detecting unit 38a is provided at the tip of a swinging arm, and the measurement is performed by the detecting unit 38a moved to a position facing the processing surface of the substrate W by swinging the arm. good. In this case, the detection unit 38a may move in accordance with the swing of the arm, or the detection unit 38a may stop intermittently to measure a plurality of locations. The number of detection units 38a is also not limited to the above embodiment. The number may be one, two, or four or more.

(2) The first volatile solvent V is not limited to IPA. For example, HFE (hydrofluoroether) or the like can be used. The silane coupling agent as a water repellent agent is not limited to HMDS. For example, TMSDEA (tetramethylsilyldiethylamine) or the like can be used. The second volatile solvent H is also not limited to the above-mentioned PGMEA. For example, IPA may be used.

(3) As long as the processing performed by the processing apparatus 110 ultimately requires cleaning and drying, the contents of the processing and the substrate processing liquid are not limited to those exemplified above. The substrate W to be processed is also not limited to those exemplified above. Furthermore, the cleaning liquid C used in the cleaning device 120 and the processing liquid used in the drying device 300 are not limited to those exemplified above. Note that the processing liquid used in the drying apparatus 300 may be any liquid that can be removed from the substrate W by centrifugal force, and the cleaning liquid C may also be included in the processing liquid here.

(4) The drying device 300 may be shared with the cleaning device 120. That is, the supply unit 15 for supplying the cleaning liquid C may be provided in the chamber 1a common to the drying device 300. Thereby, the cleaning process can be performed by supplying the cleaning liquid C from the nozzle 15a to the surface to be processed of the rotating substrate W before the drying process. For example, APM cleaning is performed by supplying APM to the processing surface of the substrate W that has been etched in the processing apparatus 110 and carried into the chamber 1a of the drying apparatus 300, and after the APM cleaning, a pure water rinsing process using DIW is performed. Accordingly, APM remaining on the surface to be processed of the substrate W may be washed away with pure water. Note that when the drying device 300 and other devices are configured as one processing device by making the drying device 300 and other devices common, such as by making the cleaning device 120 and the drying device 300 common, this device can be regarded as the drying device 300.

(5) The second volatile solvent supply unit 342 may be configured to supply the second volatile solvent H from the shielding plate 35. For example, as shown in FIG. 10, a nozzle 342a of the second volatile solvent supply unit 342 is provided so as to be able to supply the second volatile solvent H toward the vicinity of the center of the surface to be processed of the substrate W. That is, the nozzle 342a is inserted into the ventilation path 35d along the central axis and is provided so as to be movable together with the shielding plate 35. PGMA containing HMDS, which is the second volatile solvent H, is supplied to the nozzle 342a from a storage section (not shown) outside the drying chamber 31 via piping. Since the lower end of the nozzle 342a reaches the opening 35b and is directed toward the center of the substrate W, the second volatile solvent H can be supplied toward the vicinity of the center of the surface to be processed of the substrate W.

As a result, in the process of supplying the first volatile solvent V (IPA) → supplying the second volatile solvent H (PGMA containing HMDS) → supplying the first volatile solvent V (IPA) → drying, the nozzle When supplying the first volatile solvent V from the nozzle 341a to the processing surface of the substrate W, the shielding plate 35 can be positioned close to the substrate W, and the second volatile solvent V is supplied from the nozzle 342a. When supplying the solvent H, the shielding plate 35 can be positioned close to the substrate W also when supplying the first volatile solvent V from the nozzle 341a again. Therefore, in the process from the initial supply of the first volatile solvent V, the supply of the second volatile solvent H, the supply of the first volatile solvent V again, and up to drying, the above Then, the measurement unit 38 measures the film thickness of the processing liquid on the processing surface of the substrate W, and the adjustment unit 42 adjusts the measured film thickness and the gap between the opposing surface 35a and the processing surface suitable for the film thickness. The gap can be adjusted based on information indicating the Thereby, in all steps, it is possible to prevent the processing liquid from adhering to the shielding plate 35, thereby preventing the occurrence of water marks due to falling of the processing liquid.

[Other embodiments]
The embodiments of the present invention and modifications of each part have been described above, but these embodiments and modifications of each part are presented as examples, and are not intended to limit the scope of the invention. These novel embodiments described above can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included within the scope and gist of the invention, and are also included in the invention described in the claims.

1 Substrate processing apparatus 1a Chamber 1b Cassette 1c Transfer robot 1d Buffer unit 11 Cleaning chamber 11a Opening 11b Door 12 Support part 13 Rotating mechanism 14 Cup 15 Supply part 15a Nozzle 15b Moving mechanism 20 Handling device 21 Robot hand 22 Moving mechanism 31 Drying chamber 31a Opening 31b Door 31c Inlet 31d Exhaust port 31e Air supply section 31f Exhaust section 32 Support section 32a Rotary table 32b Holding member 32c Rotating shaft 33 Drive mechanism 34 Supply section 35 Shielding plate 35a Opposing surface 35b Opening 35c Support body 35d Air passage 35e Connection Port 35f Hole 36 Moving mechanism 37 Air supply section 37a Air supply device 38 Measurement section 38a Detection section 39 Cup 41 Mechanism control section 42 Adjustment section 43 Storage section 110 Processing device 120 Cleaning device 200 Transport device 300 Drying device 341 First volatility Solvent supply section 341a Nozzle 341b Storage section 342 Second volatile solvent supply section 342a Nozzle 342b Swing arm 342c Swing mechanism 400 Control device

Claims (8)

a drying room into which the substrate is transported;
a support part that receives the substrate carried into the drying chamber;
a drive mechanism that rotates the substrate supported by the support part;
a supply unit that supplies a processing liquid onto the processing surface of the rotating substrate;
a shielding plate having a facing surface facing the surface to be treated;
a moving mechanism that moves the shielding plate in a direction toward and away from the substrate;
an air supply unit that removes oxygen in the atmosphere on the surface to be processed by supplying an oxygen-free gas to a space between the opposing surface and the substrate;
a measurement unit that measures the film thickness of the treatment liquid supplied onto the surface to be treated;
an adjustment unit that adjusts the distance based on the film thickness measured by the measurement unit and information indicating a distance between the opposing surface and the processed surface suitable for the preset film thickness;
A substrate drying device having: The substrate drying apparatus according to claim 1, wherein the measuring section is provided on the shielding plate. 2. The substrate drying apparatus according to claim 1, wherein the measuring section is provided so as to be able to measure the film thickness of the processing liquid at a plurality of locations on the surface to be processed. 4. The substrate drying apparatus according to claim 3, wherein the adjustment section adjusts the distance based on a maximum film thickness among the film thicknesses at the plurality of locations. The adjustment unit adjusts a distance between the opposing surface and the processed surface of the substrate, which is suitable for the preset film thickness of the processing liquid, by raising and lowering the shielding plate using the moving mechanism. Item 1. The substrate drying device according to item 1. a processing device that processes the substrate by supplying a substrate processing liquid while rotating the substrate;
a cleaning device that cleans the substrate processed by the processing device by supplying a cleaning liquid while rotating the substrate;
A substrate drying device according to any one of claims 1 to 5,
a transport device that transports the substrate cleaned in the cleaning device with a liquid film formed by the cleaning liquid supplied by the cleaning device and transports it into the substrate drying device;
A substrate processing apparatus comprising: a processing liquid supply step in which the supply unit supplies the processing liquid onto the processing surface of the substrate rotating in the drying chamber;
a film thickness measuring step in which the measuring unit measures the film thickness of the processing liquid supplied onto the surface to be processed;
an approaching step in which a moving mechanism moves a shielding plate having a facing surface facing the surface to be processed in a direction in which the moving mechanism approaches the substrate;
an air supply step in which an air supply unit supplies oxygen-free gas to a space between the opposing surface and the substrate to eliminate oxygen in the atmosphere on the surface to be processed;
an adjustment step in which an adjustment unit adjusts the distance based on the film thickness measured by the measurement unit and information indicating a distance between the opposing surface and the treated surface suitable for the film thickness set in advance; and,
a drying step of discharging the processing liquid by centrifugal force caused by rotation of the substrate;
Substrate drying method including. The processing liquid supply step includes:
A liquid film is formed by the cleaning liquid, and the first volatile solvent is supplied from the first volatile solvent supply section in the supply section while the substrate supported by the support section is rotated by a drive mechanism. a first volatile solvent supply step of replacing the liquid film of cleaning liquid with the first volatile solvent;
A second volatile solvent containing a water repellent agent that forms a water repellent film and having a surface tension lower than that of the first volatile solvent when vaporized is supplied from a second volatile solvent supply section in the supply section. a water repellent film forming step of replacing the liquid film of the first volatile solvent with the second volatile solvent by supplying a solvent and forming the water repellent film on the substrate;
8. The substrate drying method according to claim 7, comprising:

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