Substrate processing method and substrate processing apparatus

Abstract

[Problem] To provide a technique for suppressing the generation of particulate matter at or near the center of a substrate surface. [Solution] A substrate processing method includes the following (A) to (E): (A) supplying a processing liquid to the center of a rotating substrate surface. (B) moving the supply position of the processing liquid from the center position toward a first eccentric position. (C) stopping the supply position of the processing liquid at the first eccentric position and supplying a replacement liquid to a second eccentric position different from the first eccentric position. (D) moving the supply position of the processing liquid from the first eccentric position in the opposite direction to the center position, while simultaneously moving the supply position of the replacement liquid from the second eccentric position toward the center position.

Description

[Technical Field]

[0001] This disclosure relates to a substrate processing method and a substrate processing apparatus. [Previous Technology]

[0002] The substrate processing apparatus described in Patent Document 1 supplies processing liquid directly above the center of the substrate surface, and after a liquid film of processing liquid is formed across the entire substrate surface, it supplies replacement liquid from directly above the center of the substrate surface, forming a liquid film of replacement liquid across the entire substrate surface. This substrate processing apparatus replenishes processing liquid at a location further outward than the supply location of the replacement liquid during the supply of replacement liquid. [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent No. 6118758 [Summary of the Invention]

[0004] [Problem to be Solved by the Invention] The present invention discloses a technique for suppressing the generation of particulate matter at or near the center of a substrate surface. [Means for Solving the Problem]

[0005] The substrate processing method disclosed herein includes the following (A) to (E): (A) Supplying a processing liquid to the center position of the rotating substrate surface. (B) Moving the supply position of the processing liquid from the center position to a first eccentric position. (C) Stopping the supply position of the processing liquid at the first eccentric position, and supplying a replacement liquid to a second eccentric position different from the first eccentric position. (D) Moving the supply position of the processing liquid from the first eccentric position in the opposite direction to the center position, while simultaneously moving the supply position of the replacement liquid from the second eccentric position toward the center position. [Effects of the Invention]

[0006] By means of the state disclosed herein, the generation of particles at or near the center of the substrate surface can be suppressed.

Implementation Method

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Additionally, in some drawings, the same or corresponding components are indicated by the same symbols, and descriptions are omitted.

[0009] The substrate processing method includes, for example, the steps of forming a liquid film of a pharmaceutical solution on the substrate surface; replacing the liquid film of the pharmaceutical solution with a liquid film of a rinsing solution; replacing the liquid film of the rinsing solution with a liquid film of a drying solution; and exposing the substrate surface from the liquid film of the drying solution. These processes are performed in the same processing container.

[0010] The solution is supplied to the center of the rotating substrate surface, and diffuses radially throughout the substrate surface by centrifugal force to form a liquid film. Examples of the solution used are BHF (buffered hydrofluoric acid). The solution is not limited to BHF; DHF (diluted hydrofluoric acid) is also acceptable. When using BHF, the substrate surface becomes water-repellent compared to when using DHF. Even if multiple types of solutions are supplied sequentially, in this case, a rinsing solution film is formed between the formation of the first solution's liquid film and the formation of the second solution's liquid film.

[0011] The rinsing solution is supplied to the center of the rotating substrate surface and diffuses radially across the substrate surface by centrifugal force, replacing the drug solution contained in the liquid film with the rinsing solution. The rinsing solution is used to rinse away any drug solution remaining on the substrate surface. Pure water, such as DIW (deionized water), is used as the rinsing solution.

[0012] The drying liquid is supplied to the center of the rotating substrate surface and diffuses radially across the substrate surface by centrifugal force, replacing the rinsing liquid contained in the liquid film with the drying liquid. A liquid with a surface tension lower than that of the rinsing liquid is used as the drying liquid. This can suppress the collapse of the uneven pattern caused by surface tension. Examples of drying liquids include IPA (isopropyl alcohol).

[0013] After the formation of the desiccant film, the substrate surface is exposed from the desiccant film. The desiccant is thrown off the substrate surface by rotating the substrate. At this time, the supply position of the desiccant can be moved from the center of the substrate surface to the periphery. By moving the supply position of the desiccant, an opening is formed at the center of the desiccant film, and the opening gradually widens from the center of the substrate surface to the periphery. In order to suppress the opening edge of the desiccant film, a drying gas such as nitrogen can be supplied towards the opening edge. The supply position of the drying gas follows the supply position of the desiccant.

[0014] Furthermore, in order to replace the liquid film, the nozzle located directly above the center of the substrate surface must be replaced. For example, in order to replace the liquid film of the rinsing liquid with the liquid film of the drying liquid, the nozzle located directly above the center of the substrate surface is replaced from a nozzle for rinsing liquid to a nozzle for drying liquid.

[0015] The inventors investigated the causes of particle generation at or near the center of the substrate surface and identified the cause of liquid film interruption when replacing the nozzle located directly above the center of the substrate surface. It is believed that the liquid film interruption causes liquid film residue to adhere to the substrate surface.

[0016] Next, referring to FIG1, the phenomenon of liquid film interruption at or near the center of the substrate surface during liquid film replacement will be explained. First, as shown in FIG1(A), the first nozzle 20 supplies rinsing liquid L1 to the center position P0 of the substrate surface Wa, and a liquid film F1 of rinsing liquid L1 is formed on the entire substrate surface Wa.

[0017] Next, as shown in FIG1(B), the first nozzle 20 is moved radially outward toward the substrate W, and the supply position of the rinsing liquid L1 is moved from the central position P0 to the first eccentric position P1. This is a preparation for supplying the drying liquid L2 to the second eccentric position P2, which is different from the first eccentric position P1, that is, a preparation for preventing interference between the second nozzle 30 and the first nozzle 20.

[0018] Although the second eccentric position P2 and the first eccentric position P1 are configured at approximately the same distance from the center position P0, they may be configured at different distances. The second eccentric position P2 and the first eccentric position P1 are configured near the center position P0 so that the liquid film is not interrupted near the center position P0.

[0019] Next, as shown in FIG1(C), with the supply position of the rinsing fluid L1 stopped at the first eccentric position P1, the second nozzle 30 supplies the drying fluid L2 to the second eccentric position P2. At this time, the flow rate of the rinsing fluid L1 is the first flow rate Q1. The first flow rate Q1 is set so that the liquid film will not be interrupted at or near the center position P0.

[0020] Next, as shown in Figure 1(D), the supply position of the rinsing fluid L1 moves from the first eccentric position P1 toward the peripheral position PE. The peripheral position PE is a position that moves in the opposite direction (radially outward) from the first eccentric position P1 toward the central position P0. Furthermore, the supply position of the drying fluid L2 moves from the second eccentric position P2 toward the central position P0.

[0021] In the reference example, as shown in Figure 1(D), when the supply position of the flushing fluid L1 begins to move radially outward from the first eccentric position P1, the flow rate of the flushing fluid L1 decreases from the first flow rate Q1 to the second flow rate Q2. This is to prevent the fluid from sloshing at the supply position of the flushing fluid L1.

[0022] The farther the supply position of the flushing fluid L1 is from the center position P0, the greater the circumferential velocity and centrifugal force at the supply position, and the easier it is for the boulders to be generated at the supply position. If the flow rate of the flushing fluid L1 is reduced from the first flow rate Q1 to the second flow rate Q2 in advance, the boulders at the supply position of the flushing fluid L1 can be prevented.

[0023] The first flow rate Q1 is, for example, 1200 mL / min to 1800 mL / min. The second flow rate Q2 is, for example, 800 mL / min to 1200 mL / min. Furthermore, while the flow rate of the rinsing solution L1 is reduced from the first flow rate Q1 to the second flow rate Q2, the flow rate of the drying solution L2 is maintained at a third flow rate Q3. The third flow rate Q3 is, for example, 50 mL / min to 100 mL / min.

[0024] However, as described above, when the supply position of the rinsing fluid L1 begins to move radially outward from the first eccentric position P1, and the flow rate of the rinsing fluid L1 decreases from the first flow rate Q1 to the second flow rate Q2, as shown in Figure 1(D), the liquid film is interrupted at or near the central position P0. This phenomenon occurs when the substrate surface Wa is hydrophobic. This is because the rinsing fluid L1 is easily peeled off from the substrate surface Wa and is easily washed away radially outward by centrifugal force. Examples of substrate surface Wa becoming hydrophobic include treatment with high-concentration HF, treatment with a hydrophobic resist film, and treatment with BHF. Furthermore, this phenomenon does not occur when the substrate surface Wa is hydrophilic.

[0025] In this embodiment, to accommodate the case where the substrate surface Wa is water-repellent, the timing T for reducing the flow rate of the rinsing fluid L1 from the first flow rate Q1 to the second flow rate Q2 is delayed. Timing T refers to the period after the supply position of the rinsing fluid L1 begins to move radially outward from the first eccentric position P1. Therefore, the timing T is delayed, allowing the rinsing fluid L1 to be supplied to the center position P0 as well, thus suppressing the interruption of the liquid film at or near the center position P0. Therefore, it is possible to suppress the adhesion of liquid film residue to the substrate surface due to liquid film interruption, and to suppress the generation of particulate matter at or near the center position P0.

[0026] However, after the supply position of the rinsing fluid L1 moves radially outward from the first eccentric position P1, the supply position of the drying fluid L2 reaches the center position P0, as shown in Figure 5(B). Therefore, until the supply position of the drying fluid L2 reaches the center position P0, the flow rate of the rinsing fluid L1 is reduced from the first flow rate Q1 to the second flow rate Q2.

[0027] That is, the timing T of reducing the flow rate of the flushing fluid L1 from the first flow rate Q1 to the second flow rate Q2 is until the supply position of the drying fluid L2 reaches the center position P0. Because the flow rate of the flushing fluid L1 is reduced from the first flow rate Q1 to the second flow rate Q2 before the supply position of the flushing fluid L1 is too far from the center position P0, the spring liquid at the supply position of the flushing fluid L1 can be suppressed.

[0028] In addition, timing T can be as long as the supply position of the drying liquid L2 reaches the center position P0, even if it is earlier than the arrival time, or even if it is the arrival time. However, if timing T is earlier than the supply position of the drying liquid L2 reaching the center position P0, the spring liquid at the supply position of the rinsing liquid L1 can be more suppressed.

[0029] Hereinafter, the displacement from the liquid film F1 of the rinsing liquid L1 to the liquid film F2 of the drying liquid L2 will be described. The rinsing liquid L1 is equivalent to the processing liquid described in the claims of the patent application, and the drying liquid L2 is equivalent to the displacement liquid described in the claims of the patent application.

[0030] Furthermore, the technology disclosed herein can also be applied to the replacement of the liquid film of the drug solution with the liquid film F1 of the rinsing solution L1. In this case, the drug solution is equivalent to the treatment solution described in the claims of the patent application, and the rinsing solution L1 is equivalent to the replacement solution described in the claims of the patent application.

[0031] Next, the substrate processing apparatus 1 of this embodiment will be described with reference to FIG2. In FIG2, the X-axis, Y-axis, and Z-axis are perpendicular to each other. The X-axis and Y-axis are horizontal, and the Z-axis is vertical. The substrate processing apparatus 1 processes the surface Wa of a substrate. The substrate W includes, for example, a silicon wafer or a compound semiconductor wafer. Alternatively, the substrate W may be a glass substrate.

[0032] The substrate processing apparatus 1 includes a clamp 10, a rotation mechanism 11, a first nozzle 20, a first flow controller 21, a first moving mechanism 22, a second nozzle 30, a second flow controller 31, a second moving mechanism 32, a cup body 40, and a control device 90.

[0033] The clamp 10 holds the substrate W. The clamp 10 holds the substrate W horizontally from below with the substrate surface Wa facing upward. Although the clamp 10 is a mechanical clamp in Figure 2, it can also be a vacuum clamp or an electrostatic clamp.

[0034] The rotating mechanism 11 rotates the clamp 10. The rotation axis of the clamp 10 is configured to be vertical. The clamp 10 holds the substrate W in such a way that the center of the substrate surface Wa is aligned with the rotation center line of the clamp 10.

[0035] The first nozzle 20 supplies rinsing fluid L1 to the rotating substrate surface Wa. The first nozzle 20 is positioned above the clamp 10 and supplies rinsing fluid L1 to the substrate surface Wa from above. The first nozzle 20 supplies rinsing fluid L1 vertically to the substrate surface Wa.

[0036] A first flow controller 21 and a first switching valve 23 are installed midway in the first supply line that supplies flushing fluid L1 to the first nozzle 20. When the first switching valve 23 opens the flow path of flushing fluid L1, the first nozzle 20 discharges flushing fluid L1. Its flow rate is controlled by the first flow controller 21. On the other hand, when the first switching valve 23 closes the flow path of flushing fluid L1, the first nozzle 20 stops discharging flushing fluid L1.

[0037] The first moving mechanism 22 moves the first nozzle 20, causing the supply position of the rinsing fluid L1 to move radially on the substrate surface Wa. The first moving mechanism 22 has, for example, a rotating arm 22a that holds the first nozzle 20, and a rotating mechanism 22b that rotates the rotating arm 22a. The rotating mechanism 22b may also serve as a mechanism for raising and lowering the rotating arm 22a. The rotating arm 22a is configured horizontally, holding the first nozzle 20 at one end in the long side direction, and rotating about a rotating axis extending downward from the other end in the long side direction (see Figure 3). Alternatively, the first moving mechanism 22 may have a guide rail and a linear drive mechanism instead of the rotating arm 22a and the rotating mechanism 22b. The guide rail is configured horizontally, and the linear drive mechanism moves the first nozzle 20 along the guide rail.

[0038] The second nozzle 30 supplies drying liquid L2 to the rotating substrate surface Wa. The second nozzle 30 is positioned above the clamp 10 and supplies drying liquid L2 to the substrate surface Wa from above. The second nozzle 30 supplies drying liquid L2 vertically to the substrate surface Wa.

[0039] A second flow controller 31 and a second switching valve 33 are installed midway in the second supply line that supplies the drying liquid L2 to the second nozzle 30. When the second switching valve 33 opens the flow path of the drying liquid L2, the second nozzle 30 discharges the drying liquid L2. Its flow rate is controlled by the second flow controller 31. On the other hand, when the second switching valve 33 closes the flow path of the drying liquid L2, the second nozzle 30 stops discharging the drying liquid L2.

[0040] The second moving mechanism 32 moves the second nozzle 30, causing the supply position of the drying liquid L2 to move radially on the substrate surface Wa. The second moving mechanism 32 may include, for example, a rotating arm 32a that holds the second nozzle 30, and a rotating mechanism 32b that rotates the rotating arm 32a. The rotating mechanism 32b may also function as a mechanism for raising and lowering the rotating arm 32a. The rotating arm 32a is configured horizontally, holding the second nozzle 30 at one end in the long side direction, and rotating about a rotating axis extending downward from the other end in the long side direction (see Figure 3). Alternatively, the second moving mechanism 32 may have a guide rail and a linear drive mechanism instead of the rotating arm 32a and the rotating mechanism 32b. The guide rail is configured horizontally, and the linear drive mechanism moves the second nozzle 30 along the guide rail.

[0041] The cup body 40 is used to receive the substrate W and recover the rinsing liquid L1 and drying liquid L2 that are discarded from the surface of the substrate W. The cup body 40 includes a cylindrical portion 41, a bottom cover portion 42, and an inclined portion 43. The cylindrical portion 41 has an inner diameter larger than the diameter of the substrate W and is configured vertically. The bottom cover portion 42 closes the opening at the lower end of the cylindrical portion 41. The inclined portion 43 is formed around the entire upper end of the cylindrical portion 41 and is inclined upwards towards the radially inward side of the cylindrical portion 41.

[0042] The control device 90 controls the rotation mechanism 11, the first flow controller 21, the first moving mechanism 22, the second flow controller 31, and the second moving mechanism 32, etc. The control device 90 is, for example, a computer, as shown in FIG2, equipped with a CPU (Central Processing Unit) 91 and a memory medium 92. The memory medium 92 stores programs that control various processes executed in the board processing device 1. The control device 90 controls the operation of the board processing device 1 by causing the CPU 91 to execute the programs stored in the memory medium 92.

[0043] Next, referring to Figures 4, 5 and 6, the substrate processing method of this embodiment will be described. The processes shown in Figures 4, etc., are performed under the control of the control device 90.

[0044] First, in S101 of FIG4, as shown in FIG1(A), the first nozzle 20 supplies rinsing liquid L1 to the center position of the rotating substrate surface Wa, and forms a liquid film F1 of rinsing liquid L1 on the entire substrate surface Wa.

[0045] Next, in S102, the first moving mechanism 22 initiates the movement of the first nozzle 20. The supply position of the flushing fluid L1 begins to move from the center position P0 toward the first eccentric position P1.

[0046] Next, in S103, as shown in FIG1(B), the first moving mechanism 22 stops the movement of the first nozzle 20, so that the supply position of the flushing fluid L1 stops at the first eccentric position P1.

[0047] Next, in S104, as shown in FIG1(C), with the first moving mechanism 22 stopping the supply position of the rinsing fluid L1 at the first eccentric position P1, the second nozzle 30 supplies the drying fluid L2 to the second eccentric position P2. At this time, the flow rate of the rinsing fluid L1 is the first flow rate Q1.

[0048] Next, in S105, as shown in FIG5(A), the first moving mechanism 22 initiates the movement of the first nozzle 20. The supply position of the rinsing fluid L1 begins to move radially outward from the first eccentric position P1. Furthermore, the second moving mechanism 32 initiates the movement of the second nozzle 30. The supply position of the drying fluid L2 begins to move from the second eccentric position P2 toward the center position P0.

[0049] Next, in S106, as shown in FIG5(B), the first flow controller 21 reduces the flow rate of the flushing fluid L1 from the first flow rate Q1 to the second flow rate Q2. Since its timing T is after the supply position of the flushing fluid L1 starts to move radially outward from the first eccentric position P1, the flushing fluid L1 or the drying fluid L2 can also be supplied to the center position P0 to suppress the interruption of the liquid film at or near the center position P0.

[0050] Next, in S107, as shown in FIG5(C), when the supply position of the drying liquid L2 reaches the center position P0, the second moving mechanism 32 stops the movement of the second nozzle 30. The second nozzle 30 supplies the drying liquid L2 to the center position P0. The drying liquid L2 begins to diffuse from the center position P0 toward the peripheral position PE.

[0051] After the supply position of the drying liquid L2 reaches the center position P0, the rotation mechanism 11 can reduce the rotation number of the substrate W from the first rotation number R1 to the second rotation number R2, as shown in FIG6. This is a preparation to cover the entire substrate surface Wa with the liquid film F2 of the drying liquid L2.

[0052] The drying liquid L2 has higher volatility than the rinsing liquid L1. Therefore, by reducing the number of rotations of the substrate W, the thickness of the liquid film F2 of the drying liquid L2 is increased, suppressing the evaporation of the drying liquid L2 and preventing the exposure of the substrate surface Wa. The further outward the substrate surface Wa is radially, the greater the centrifugal force acting on the liquid film F2, and the thinner the liquid film F2 becomes. Thus, before the drying liquid L2 diffuses at the peripheral position PE, the rotation mechanism 11 reduces the number of rotations of the substrate W from a first rotation number R1 to a second rotation number R2. The first rotation number R1 is, for example, 1000 rpm to 1400 rpm. The second rotation number R2 is, for example, 500 rpm to 900 rpm.

[0053] In this embodiment, with the supply position of the drying liquid L2 fixed at the central position P0, the supply position of the rinsing liquid L1 is moved towards the peripheral position PE. When the drying liquid L2 diffuses from the central position P0 to the peripheral position PE, the rinsing liquid L1 can be supplied in front of the drying liquid L2, which can suppress the interruption of the liquid film. Therefore, the generation of particulate matter at the peripheral position PE can be suppressed.

[0054] Next, in S108, as shown in FIG5(D), when the supply position of the flushing fluid L1 reaches the peripheral position PE, the first moving mechanism 22 stops the movement of the first nozzle 20. The first nozzle 20 supplies flushing fluid L1 to the peripheral position PE.

[0055] Finally, in S109, as shown in FIG5(E), the first nozzle 20 stops supplying the flushing fluid L1. Accordingly, the displacement from the liquid film F1 of the flushing fluid L1 to the liquid film F2 of the drying fluid L2 ends.

[0056] Figure 7(A) shows the distribution of particles on the substrate surface Wa after processing using the substrate processing method of Figure 5. Figure 7(B) shows the distribution of particles on the substrate surface Wa after processing using the substrate processing method of Figure 1. In Figures 7(A) and (B), black circles represent particles.

[0057] The experimental conditions in Figures 7(A) and 7(B) are as follows. The substrate W is a silicon wafer, and the diameter of the substrate surface Wa is 300 mm. The substrate surface Wa was pretreated with BHF to make it hydrophobic. The first rotation number R1 is 1200 rpm, the second rotation number R2 is 700 rpm, the first flow rate Q1 is 1500 mL / min, the second flow rate Q2 is 1000 mL / min, and the third flow rate Q3 is 75 mL / min.

[0058] Comparing Figure 7(A) and Figure 7(B), it is clear that if the time delay T of reducing the flow rate of the flushing fluid L1 from the first flow rate Q1 to the second flow rate Q2 is increased, the generation of particles at or near the center position P0 can be suppressed.

[0059] Next, the substrate processing method according to the first modified example will be described with reference to FIG8. Hereinafter, the differences between this modified example (FIG8) and the above-described embodiment (FIG6) will be mainly described.

[0060] In this modified example, as shown in FIG8, when the supply position of the rinsing fluid L1 begins to move radially outward from the first eccentric position P1 (S105 in FIG4, FIG5(A)), the second flow controller 31 increases the flow rate of the drying fluid L2 from the third flow rate Q3 to the fourth flow rate Q4. The fourth flow rate Q4 is, for example, 120 mL / min to 180 mL / min.

[0061] When the supply position of the rinsing fluid L1 begins to move radially outward from the first eccentric position P1, the flow rate of the drying fluid L2 increases, so the drying fluid L2 also reaches the central position P0. Therefore, the interruption of the liquid film at or near the central position P0 can be suppressed.

[0062] When the supply position of the drying liquid L2 reaches the center position P0, the second flow controller 31 reduces the flow rate of the drying liquid L2 from the fourth flow rate Q4 to the fifth flow rate Q5. The fifth flow rate Q5 is, for example, 50 mL / min to 100 mL / min. The fifth flow rate Q5 can be less than the fourth flow rate Q4, or it can be the same as the third flow rate Q3.

[0063] In this variation, when the supply position of the drying liquid L2 reaches the center position P0, the second flow controller 31 reduces the flow rate of the drying liquid L2 from the fourth flow rate Q4 to the fifth flow rate Q5. If the supply position of the drying liquid L2 reaches the center position P0, the drying liquid L2 has indeed reached the center position P0.

[0064] Furthermore, in this modified example, similar to the above embodiment, the timing T for reducing the flow rate of the rinsing fluid L1 from the first flow rate Q1 to the second flow rate Q2 can be either after the supply position of the rinsing fluid L1 begins to move radially outward from the first eccentric position P1, or even at the beginning (see Figure 1). At this time, if the flow rate of the drying fluid L2 increases from the third flow rate Q3 to the fourth flow rate Q4, the interruption of the liquid film at or near the center position P0 can be suppressed.

[0065] Next, the substrate processing method according to the second modified example will be described with reference to FIG9. Hereinafter, the differences between this modified example (FIG. 9) and the above-described embodiment (FIG. 6) will be mainly described.

[0066] In this modified example, as shown in FIG9, when the supply position of the rinsing fluid L1 begins to move radially outward from the first eccentric position P1, the rotating mechanism 11 reduces the rotation number of the substrate W from the first rotation number R1 to the third rotation number R3. The third rotation number R3 is, for example, 800 rpm to 1200 rpm. The third rotation number R3 can be less than the first rotation number R1.

[0067] When the supply position of the rinsing liquid L1 begins to move radially outward from the first eccentric position P1, the rotation speed of the substrate W decreases, the centrifugal force decreases, and the rinsing liquid L1 or the drying liquid L2 also reaches the center position P0. Therefore, the interruption of the liquid film at or near the center position P0 can be suppressed.

[0068] When the supply position of the drying liquid L2 reaches the center position P0, the rotation mechanism 11 further reduces the rotation number of the substrate W from the third rotation number R3 to the second rotation number R2. The third rotation number R3 is less than the first rotation number R1 and greater than the second rotation number R2. The second rotation number R2 is, for example, 500 rpm to 900 rpm.

[0069] In this modified example, when the supply position of the drying liquid L2 reaches the center position P0, the rotation mechanism 11 reduces the rotation number of the substrate W from the third rotation number R3 to the second rotation number R2. If the supply position of the drying liquid L2 reaches the center position P0, the drying liquid L2 reliably reaches the center position P0.

[0070] Furthermore, in this modified example, although the third rotation number R3 is greater than the second rotation number R2, it is acceptable even if it is the same as the second rotation number R2. This reduces the manpower and time required for changing the rotation number.

[0071] Furthermore, in this modified example, similar to the embodiment described above, the timing T for reducing the flow rate of the rinsing fluid L1 from the first flow rate Q1 to the second flow rate Q2 can be either after the supply position of the rinsing fluid L1 begins to move radially outward from the first eccentric position P1, or even at the beginning (see Figure 1). At this time, if the number of rotations of the substrate W decreases from the first number of rotations R1 to the third number of rotations R3, it is possible to suppress the interruption of the liquid film at or near the center position P0.

[0072] The interruption of the liquid film at or near the center position P0 can be achieved by at least one of (1) to (3) below. The combination is not particularly limited, and all of (1) to (3) below can be combined. (1) After the supply position of the rinsing liquid L1 is moved radially outward from the first eccentric position P1, the flow rate of the rinsing liquid L1 is reduced from the first flow rate Q1 to the second flow rate Q2. (2) When the supply position of the rinsing liquid L1 is moved radially outward from the first eccentric position P1, the flow rate of the drying liquid L2 is reduced from the third flow rate Q3 to the fourth flow rate Q4. (3) When the supply position of the rinsing liquid L1 is moved radially outward from the first eccentric position P1, the rotation number of the substrate W is reduced from the first rotation number R1 to the third rotation number R3.

[0073] Next, the inspection device 50 of the substrate processing apparatus 1 will be described with reference to FIG10. The inspection device 50 checks the wettability of the rinsing liquid L1 relative to the substrate surface Wa. For example, the inspection device 50 checks the substrate surface Wa in a state where a liquid film F1 of the rinsing liquid L1 is formed on the substrate surface Wa, and performs image processing on the image captured by a camera 51 or the like, and determines the wettability by whether the entire substrate surface Wa is covered by the liquid film F1. In addition, the camera 51 can be placed inside the processing container such as the housing clamp 10, or it can be placed outside the processing container.

[0074] As shown in Figure 10, when the entire substrate surface Wa is not covered by the liquid film F1, and the periphery of the substrate surface Wa is exposed from the liquid film F1, the rinsing liquid L1 has poor wettability on the substrate surface Wa, and the inspection device 50 determines it to be hydrophobic. When the substrate surface Wa is hydrophobic, the rinsing liquid L1 is easily peeled off, and the periphery of the substrate surface Wa is exposed. This is because the centrifugal force is greater at the periphery of the substrate surface Wa compared to the center. On the other hand, when the entire substrate surface Wa is covered by the liquid film F1, the rinsing liquid L1 has good wettability on the substrate surface Wa, and the inspection device 50 determines it to be hydrophilic.

[0075] The control device 90 determines the timing T for reducing the flow rate of the rinsing fluid L1 from the first flow rate Q1 to the second flow rate Q2 based on the inspection result of the inspection device 50. Specifically, as shown in FIG10, when the substrate surface Wa is not covered by the liquid film F1 and the periphery of the substrate surface Wa is exposed from the liquid film F1, the timing T is set to be when the supply position of the rinsing fluid L1 starts to move radially outward from the first eccentric position P1 and the supply position of the drying fluid L2 reaches the center position P0. On the other hand, when the entire substrate surface Wa is covered by the liquid film F1, the timing T is set to be when the supply position of the rinsing fluid L1 starts to move radially outward from the first eccentric position P1.

[0076] Although the above description pertains to embodiments of the substrate processing method and substrate processing apparatus disclosed herein, this disclosure is not limited to the aforementioned embodiments. Various modifications, alterations, substitutions, additions, deletions, and combinations are possible within the scope of the claims. Even these modifications and alterations naturally fall within the technical scope of this disclosure.

[0077] This application claims priority based on Japanese Patent Application No. 2020-037866 filed with the Japan Patent Office on March 5, 2020, and incorporates the entire contents of Japanese Patent Application No. 2020-037866 in this application. [Simplified Explanation of the Diagram]

[0007] [Figure 1(A)] is a diagram showing an example of S101 in Figure 4, [Figure 1(B)] is a diagram showing an example of S103 in Figure 4, [Figure 1(C)] is a diagram showing an example of S104 in Figure 4, and [Figure 1(D)] is a diagram showing a reference example of a step continuing from Figure 1(C). [Figure 2] is a diagram showing a substrate processing apparatus according to an embodiment. [Figure 3] is a diagram showing an example of the first moving mechanism and the second moving mechanism. [Figure 4] is a flowchart showing a substrate processing method according to an embodiment. [Figure 5(A)] is a diagram showing an example of S105 in Figure 4; [Figure 5(B)] is a diagram showing an example of S106 in Figure 4; [Figure 5(C)] is a diagram showing an example of S107 in Figure 4; [Figure 5(D)] is a diagram showing an example of S108 in Figure 4; [Figure 5(E)] is a diagram showing an example of S109 in Figure 4. [Figure 6] is a table showing a substrate processing method according to one embodiment. [Figure 7(A)] is a diagram showing the distribution of particles on the surface of a substrate after processing by the substrate processing method of Figure 5; [Figure 7(B)] is a diagram showing the distribution of particles on the surface of a substrate after processing by the substrate processing method of Figure 1. [Figure 8] is a table showing a substrate processing method according to a first modified example. [Figure 9] is a table showing a substrate processing method according to a second modified example. [Figure 10] is a diagram showing an example of an inspection device of a substrate processing apparatus.

Claims

1. A substrate processing method comprising: supplying a processing liquid to a center position on the surface of a rotating substrate; moving the supply position of the processing liquid from the center position to a first eccentric position; stopping the supply position of the processing liquid at the first eccentric position and supplying a replacement liquid to a second eccentric position different from the first eccentric position; and moving the supply position of the processing liquid from the first eccentric position in the opposite direction to the center position while simultaneously moving the supply position of the replacement liquid from the second eccentric position toward the center position.

2. The substrate processing method of claim 1, wherein when the processing liquid is supplied to the first eccentric position, the surface of the substrate is rotated by a first rotation number, and when the supply position of the processing liquid begins to move from the first eccentric position in a direction opposite to the center position, the rotation number of the surface of the substrate is less than the first rotation number.

3. The substrate processing method of claim 1 or 2, wherein, while the supply position of the replacement liquid is fixed at the center position, a step is taken to continuously move the supply position of the processing liquid in the opposite direction to the center position.

4. The substrate processing method of claim 1 or 2, wherein when the replacement liquid is supplied to the second eccentric position at a third flow rate, and the supply position of the processing liquid begins to move from the first eccentric position in the opposite direction to the center position, the flow rate of the replacement liquid is increased from the third flow rate to the fourth flow rate.

5. A substrate processing apparatus comprising: a clamp for holding a substrate; a rotation mechanism for rotating the clamp; a first nozzle for supplying a processing liquid to the surface of the rotating substrate; a first moving mechanism for moving the first nozzle to move the supply position of the processing liquid radially toward the surface of the substrate; a second nozzle for supplying a displacement liquid to the surface of the rotating substrate; a second moving mechanism for moving the second nozzle to move the supply position of the displacement liquid radially toward the surface of the substrate; and a control device for controlling the rotation mechanism, the first moving mechanism, and the second moving mechanism to perform the substrate processing method as described in any one of claims 1 to 3.

6. A substrate processing apparatus comprising: a clamp for holding a substrate; a rotation mechanism for rotating the clamp; a first nozzle for supplying a processing liquid to the surface of the rotating substrate; a first flow controller for controlling the flow rate of the processing liquid supplied through the first nozzle; a first moving mechanism for moving the first nozzle to move the supply position of the processing liquid radially toward the surface of the substrate; a second nozzle for supplying a displacement liquid to the surface of the rotating substrate; a second flow controller for controlling the flow rate of the displacement liquid supplied through the second nozzle; a second moving mechanism for moving the second nozzle to move the supply position of the displacement liquid radially toward the surface of the substrate; and a control device for controlling the rotation mechanism, the first moving mechanism, the first flow controller, the second moving mechanism, and the second flow controller to perform the substrate processing method of claim 4.

7. The substrate processing apparatus of claim 5 or 6, further comprising an inspection device for inspecting the wettability of the processing liquid on the surface of the substrate.

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