Method for cleaning substrate processing equipment and liquid receiving container

Abstract

To clean a liquid reception container over a wide range.SOLUTION: A substrate processing apparatus comprises: a holding unit; a heating mechanism; a cleaning liquid supply unit; a liquid reception container; and a control unit. The holding unit rotatably holds a substrate. The heating mechanism heats the substrate held by the holding unit. The cleaning liquid supply unit supplies cleaning liquid to the substrate. The liquid reception container is arranged in the circumference of the holding unit. The control unit controls each unit. The control unit implements a heating processing and a first cleaning processing. The heating processing heats the substrate held by the holding unit by using the heating mechanism. The first cleaning processing supplies the cleaning liquid to the substrate which is rotated from the cleaning liquid supply unit to generate warpage at an outer edge portion of the substrate, and cleans a first region of the liquid reception container by the cleaning liquid scattered from the outer edge portion.SELECTED DRAWING: Figure 4

Description

Technical Field

[0006] , , , ,

[0001] The present disclosure relates to a substrate processing apparatus and a method for cleaning a liquid receiving container.

Background Art

[0002] Conventionally, in a substrate processing apparatus that supplies a processing liquid to a substrate such as a semiconductor wafer or a glass substrate to perform various processes, a technique for cleaning a liquid receiving container provided so as to surround the periphery of the substrate is known.

[0003] For example, Patent Document 1 discloses a technique in which a special cleaning substrate having a shape different from that of the substrate to be processed is held using a rotatable holding portion, a cleaning liquid is supplied to the rotating cleaning substrate, and the liquid receiving container is cleaned by the cleaning liquid scattered from the peripheral portion of the cleaning substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present disclosure provides a technique capable of cleaning a liquid receiving container over a wide range.

Means for Solving the Problems

[0006] A substrate processing apparatus according to one aspect of the present disclosure comprises a holding unit, a heating mechanism, a cleaning liquid supply unit, a liquid receiving container, and a control unit. The holding unit rotatably holds the substrate. The heating mechanism heats the substrate held by the holding unit. The cleaning liquid supply unit supplies cleaning liquid to the substrate. The liquid receiving container is arranged around the holding unit. The control unit controls each unit. The control unit performs a heating treatment and a first cleaning treatment. The heating treatment heats the substrate held by the holding unit using the heating mechanism. The first cleaning treatment supplies cleaning liquid from the cleaning liquid supply unit to the rotating substrate to cause warping at the periphery of the substrate and cleans a first area of ​​the liquid receiving container with cleaning liquid splashed from the periphery. [Effects of the Invention]

[0007] According to this disclosure, the liquid receiving container can be cleaned over a wide area. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a diagram showing a schematic configuration of a substrate processing system according to an embodiment of this system. [Figure 2] Figure 2 is a schematic plan view showing the configuration of the processing unit according to the embodiment. [Figure 3] Figure 3 is a schematic cross-sectional view showing the configuration of a processing unit according to an embodiment. [Figure 4] Figure 4 is a flowchart showing a series of processing steps performed by the processing unit according to this embodiment. [Figure 5] Figure 5 is a timing chart showing an example of the operation of each part in the first and second cleaning processes according to the embodiment. [Figure 6] Figure 6 shows examples of the operation of the first supply unit and the third supply unit in the first and second cleaning processes according to the embodiment. [Figure 7] Figure 7 shows examples of the operation of the first supply unit and the third supply unit in the first and second cleaning processes according to the embodiment. [Figure 8]Figure 8 illustrates an example of adjusting the amount of warping due to heat distortion using heater temperature. [Figure 9] Figure 9 illustrates an example of adjusting the amount of thermal warping by changing the supply position of the rinsing solution. [Figure 10] Figure 10 is a diagram illustrating an example of adjusting the amount of thermal warping of a wafer by changing its rotation speed. [Figure 11] Figure 11 is a schematic diagram showing the configuration of a processing unit according to a modified example 1 of the embodiment. [Figure 12] Figure 12 is a flowchart showing the procedure for the cleaning content determination process performed by the processing unit according to the modified embodiment 1. [Figure 13] Figure 13 is a schematic diagram showing the configuration of a processing unit according to a modified example 2 of the embodiment. [Figure 14] Figure 14 is a flowchart showing the procedure for the hydrophilization treatment performed by the treatment unit according to the modified embodiment 2. [Figure 15] Figure 15 shows an example of the operation of the first supply unit, the second supply unit, and the third supply unit in the first cleaning process according to a modified example 3 of the embodiment. [Modes for carrying out the invention]

[0009] The embodiments for implementing the substrate processing apparatus and liquid receiving container cleaning method according to this disclosure (hereinafter referred to as "embodiments") will be described in detail below with reference to the drawings. However, this disclosure is not limited by these embodiments. Furthermore, each embodiment can be combined as appropriate, provided that the processing content is not inconsistent. Also, the same parts are denoted by the same reference numerals in each of the following embodiments, and redundant descriptions are omitted.

[0010] Furthermore, in the embodiments described below, expressions such as "constant," "orthogonal," "perpendicular," or "parallel" may be used, but these expressions do not require strict adherence to "constant," "orthogonal," "perpendicular," or "parallel" conditions. In other words, each of the above expressions allows for deviations, for example, in manufacturing accuracy or installation accuracy.

[0011] In addition, in each of the drawings referred to below, in order to make the explanation easier to understand, an orthogonal coordinate system may be shown that defines the X-axis direction, Y-axis direction, and Z-axis direction that are orthogonal to each other, with the positive Z-axis direction being the vertically upward direction. Also, the rotational direction about the vertical axis may be referred to as the θ direction.

[0012] There is a technique in which a special cleaning substrate having a different shape from the substrate to be processed is held using a rotatable holding unit, a cleaning liquid is supplied to the rotating cleaning substrate, and the liquid receiving container is cleaned by the cleaning liquid scattered from the peripheral portion of the cleaning substrate.

[0013] By the way, in the cleaning method using a cleaning substrate with a special shape as in the above technique, there is a problem that the process becomes complicated because a step of replacing the substrate to be processed with the cleaning substrate is added.

[0014] Therefore, a technique that can clean the liquid receiving container over a wide range without using a cleaning substrate with a special shape is expected.

[0015] FIG. 1 is a diagram showing a schematic configuration of a substrate processing system according to an embodiment. As shown in FIG. 1, the substrate processing system 1 includes a loading / unloading station 2 and a processing station 3. The loading / unloading station 2 and the processing station 3 are provided adjacent to each other.

[0016] The loading / unloading station 2 includes a carrier placement unit 11 and a transfer unit 12. On the carrier placement unit 11, a plurality of carriers C for horizontally accommodating a plurality of substrates, in this embodiment, semiconductor wafers (hereinafter referred to as wafers W), are placed.

[0017] The transport unit 12 is provided adjacent to the carrier mounting unit 11 and contains a substrate transport device 13 and a transfer unit 14. The substrate transport device 13 includes a wafer holding mechanism for holding wafers W. The substrate transport device 13 is capable of moving horizontally and vertically, as well as rotating about a vertical axis, and uses the wafer holding mechanism to transport wafers W between the carrier C and the transfer unit 14.

[0018] The processing station 3 is located adjacent to the transport unit 12. The processing station 3 comprises a transport unit 15 and a plurality of processing units 16 (an example of a substrate processing device). The plurality of processing units 16 are arranged side by side on both sides of the transport unit 15. The number of processing units 16 provided in the substrate processing system 1 is not limited to the illustrated example.

[0019] The transport unit 15 includes a substrate transport device 17 inside. The substrate transport device 17 includes a wafer holding mechanism for holding wafers W. The substrate transport device 17 is capable of moving horizontally and vertically, as well as rotating about a vertical axis, and transports wafers W between the transfer unit 14 and the processing unit 16 using the wafer holding mechanism.

[0020] The processing unit 16 performs predetermined substrate processing on the wafer W transported by the substrate transport device 17. The processing unit 16 also uses the wafer W transported by the substrate transport device 17 to perform a cleaning process on the outer cup 80 (see Figures 2 and 3), which will be described later.

[0021] Furthermore, the substrate processing system 1 includes a control device 4. The control device 4 is, for example, a computer and comprises a control unit 18 and a storage unit 19. The storage unit 19 is implemented by, for example, semiconductor memory elements such as RAM and flash memory, or storage devices such as hard disks and optical discs, and stores programs that control various processes executed in the processing unit 16. The control unit 18 includes a microcomputer having a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), input / output ports, and various circuits, and controls the operation of the processing unit 16 by reading and executing the programs stored in the storage unit 19.

[0022] Furthermore, such a program may have been recorded on a computer-readable storage medium and installed from that storage medium to the storage unit 19 of the control device 4. Examples of computer-readable storage mediums include hard disks (HDs), flexible disks (FDs), compact disks (CDs), magnetic optical disks (MOs), and memory cards.

[0023] In the substrate processing system 1 configured as described above, first, the substrate transport device 13 of the loading / unloading station 2 takes out a wafer W from the carrier C placed on the carrier mounting section 11 and places the removed wafer W on the transfer section 14. The wafer W placed on the transfer section 14 is then taken out of the transfer section 14 by the substrate transport device 17 of the processing station 3 and transported to the processing unit 16.

[0024] The wafer W, which has been brought into the processing unit 16, is processed by the processing unit 16 and then removed from the processing unit 16 by the substrate transport device 17 and placed on the transfer unit 14. The processed wafer W, which has been placed on the transfer unit 14, is then returned to the carrier C of the carrier placement unit 11 by the substrate transport device 13.

[0025] Next, the configuration of the processing unit 16 according to the embodiment will be described with reference to Figures 2 and 3. Figure 2 is a schematic plan view showing the configuration of the processing unit 16 according to the embodiment. Figure 3 is a schematic cross-sectional view showing the configuration of the processing unit 16 according to the embodiment. Note that Figure 3 schematically shows the cross-section as seen by the line III-III in Figure 2.

[0026] As shown in Figures 2 and 3, the processing unit 16 comprises a processing container 10, a holding unit 20, and a heating mechanism 30. The processing unit 16 also comprises a first supply unit 40 (a cleaning liquid supply unit and an example of the first cleaning liquid supply unit), a second supply unit 50 (a cleaning liquid supply unit and an example of the second cleaning liquid supply unit), a third supply unit 60 (an example of a cleaning liquid supply unit), a lower cup 70, and an outer cup 80.

[0027] The processing container 10 houses a holding section 20, a heating mechanism 30, a first supply section 40, a second supply section 50, a third supply section 60, a lower cup 70, and an outer cup 80.

[0028] The holding unit 20 rotatably holds the wafer W. Specifically, the holding unit 20 comprises a vacuum chuck 21, a shaft 22, and a drive unit 23. The vacuum chuck 21 holds the wafer W by suction using vacuum. The vacuum chuck 21 has a smaller diameter than the wafer W and holds the center of the back surface of the wafer W by suction. The shaft 22 horizontally supports the vacuum chuck 21 at its tip. The drive unit 23 is connected to the base end of the shaft 22 and rotates the shaft 22 around a vertical axis. The wafer W is held horizontally with its front surface facing upward relative to the holding unit 20.

[0029] The heating mechanism 30 is positioned below the wafer W and outside the holding portion 20. Specifically, the heating mechanism 30 is positioned between the holding portion 20 and the lower cup 70.

[0030] The heating mechanism 30 heats the wafer W held in the holding section 20 by supplying a heated fluid to the back surface of the wafer W. Specifically, the heating mechanism 30 comprises a plurality of discharge ports 35b arranged in the circumferential direction of the wafer W and capable of discharging fluid, and a heater (not shown) for heating the fluid, and supplies heated fluid to the back surface of the wafer W from these plurality of discharge ports 35b. The heated fluid may be, for example, heated N2 gas.

[0031] The multiple discharge ports 35b of the heating mechanism 30 are located radially inward of the wafer W from the peripheral edge of the wafer W when the processing unit 16 is viewed from above. For example, the peripheral edge of the wafer W is an annular region with a width of about 1 mm to 25 mm, with the end face of the wafer W as the outermost edge. The multiple discharge ports 35b supply heated fluid to the back surface of the wafer W, which is radially inward of the wafer W from the peripheral edge of the wafer W. Alternatively, the multiple discharge ports 35b of the heating mechanism 30 may be arranged concentrically around the center of the wafer W when the processing unit 16 is viewed from above.

[0032] The first supply unit 40 supplies processing liquid to the peripheral edge on the front side of the wafer W or to the central part on the front side of the wafer W. The first supply unit 40 comprises a first nozzle 41, an arm 42, and a moving mechanism 43.

[0033] The first nozzle 41 is positioned above the wafer W with its discharge opening facing downwards. The first nozzle 41 discharges a processing liquid, such as a chemical solution or a rinsing solution (an example of a cleaning solution), to the peripheral edge or the central part of the front surface of the wafer W. The chemical solution is, for example, a chemical solution that etches and removes a film formed on the front surface of the wafer W. Examples of chemical solutions that can be used include hydrofluoric acid (HF), dilute hydrofluoric acid (DHF), and hydrofluoric acid. Hydrofluoric acid is a mixture of hydrofluoric acid (HF) and nitric acid (HNO3). For example, DIW (deionized water) can be used as the rinsing solution.

[0034] The temperature of the processing liquid discharged from the first nozzle 41 is lower than the temperature of the wafer W heated by the heating mechanism 30. For example, the temperature of the wafer W heated by the heating mechanism 30 is about 100°C. On the other hand, the temperature of the processing liquid discharged from the first nozzle 41 is room temperature (about 20°C to 25°C).

[0035] The arm 42 extends horizontally (in this case, in the Y-axis direction) and supports the first nozzle 41 at its tip. The moving mechanism 43 is connected to the base end of the arm 42 and moves the arm 42, for example, along the horizontal direction (in this case, in the X-axis direction), as well as rotating and raising and lowering the arm 42. The moving mechanism 43 allows the arm 42 to move the first nozzle 41 between a first processing position above the periphery of the wafer W, a second processing position above the center of the wafer W, and a retracted position outside the wafer W.

[0036] The second supply unit 50 supplies processing liquid to the peripheral edge on the front side of the wafer W. The second supply unit 50 comprises a second nozzle 51, an arm 52, and a moving mechanism 53.

[0037] The second nozzle 51 is positioned above the wafer W with its discharge opening facing downwards. The second nozzle 51 discharges the processing liquid to the peripheral edge on the front side of the wafer W.

[0038] The temperature of the processing liquid discharged from the second nozzle 51 is lower than the temperature of the wafer W heated by the heating mechanism 30. For example, the temperature of the processing liquid discharged from the second nozzle 51 is room temperature.

[0039] The arm 52 extends horizontally (in this case, in the Y-axis direction) and supports the second nozzle 51 at its tip. The moving mechanism 53 is connected to the base end of the arm 52 and moves the arm 52, for example, horizontally (in this case, in the X-axis direction). The moving mechanism 53 allows the arm 52 to move the second nozzle 51 between a third processing position above the periphery of the wafer W and a retracted position outside the wafer W.

[0040] The third supply unit 60 supplies processing liquid to the peripheral edge of the back surface of the wafer W. As shown in Figure 3, the third supply unit 60 includes a back surface nozzle 61, piping 62, a valve 63, a flow rate regulator 64, and a processing liquid supply source 65.

[0041] The back nozzle 61 is positioned below the wafer W and discharges the processing liquid toward the back edge of the wafer W.

[0042] Furthermore, the supply position of the processing liquid on the back surface of the wafer W may be radially inward than the supply position of the processing liquid on the front surface of the wafer W. For example, the supply position of the processing liquid on the front surface of the wafer W may be 1 mm radially inward from the edge face of the wafer W. Alternatively, the supply position of the processing liquid on the back surface of the wafer W may be 3 mm radially inward from the edge face of the wafer W.

[0043] Although not shown in the diagram here, the third supply unit 60 may be equipped with a moving mechanism for moving the back nozzle 61 horizontally. In this case, the third supply unit 60 can move the back nozzle 61 between a fourth processing position below the periphery of the wafer W and a retracted position outside the wafer W.

[0044] The piping 62 connects the rear nozzle 61 to the processing liquid supply source 65. A valve 63 is installed in the middle of the piping 62 to open and close the piping 62. A flow regulator 64 is installed in the middle of the piping 62 to adjust the flow rate of the processing liquid flowing through the piping 62. The processing liquid supply source 65 is, for example, a tank that stores the processing liquid.

[0045] The lower cup 70 is an annular member positioned below the wafer W and outside the heating mechanism 30. The lower cup 70 is made of a highly chemical-resistant material such as fluororesin, PTFE (polytetrafluoroethylene) or PFA (perfluoroalkoxyalkane).

[0046] The outer cup 80 is an annular component provided to surround the wafer W and to catch any liquid splashed from the wafer W. A drain port 81 is formed at the bottom of the outer cup 80. The chemical solution, rinse solution, etc., caught by the outer cup 80 is stored in the space formed by the outer cup 80 and the lower cup 70, and then discharged to the outside of the processing unit 16 through the drain port 81.

[0047] Next, a series of processing steps performed by the processing unit 16 according to this embodiment will be described with reference to Figure 4. Figure 4 is a flowchart showing a series of processing steps performed by the processing unit 16 according to this embodiment. Each processing step shown in Figure 4 is executed according to the control of the control unit 18.

[0048] As shown in Figure 4, the processing unit 16 first performs a loading process (step S101). In the loading process, the wafer W is loaded into the processing container 10 of the processing unit 16 by the substrate transport device 17 (see Figure 1). The loaded wafer W is held by the holding section 20 of the processing unit 16.

[0049] Next, the processing unit 16 starts rotating and heating the wafer W (step S102). The wafer W is rotated by rotating the vacuum chuck 21 using the drive unit 23 of the holding unit 20. The wafer W is heated using the heating mechanism 30. The rotation of the wafer W continues until the processing in step S104 is completed. The heating of the wafer W also continues at least until the processing in step S103 is completed.

[0050] Next, the processing unit 16 performs a first cleaning process (step S103). In the first cleaning process, the processing unit 16 supplies rinsing liquid to the rotating wafer W from the first supply unit 40 and the third supply unit 60. Specifically, the processing unit 16 moves the first nozzle 41 to the first processing position and the back nozzle 61 to the fourth processing position, and then supplies rinsing liquid from the first supply unit 40 and the third supply unit 60 to a position closer to the periphery of the wafer W than to the center of the wafer W. When rinsing liquid at a lower temperature than the wafer W is supplied to the periphery of the wafer W, heat is removed from the periphery of the wafer W, creating a temperature difference between the periphery and other areas of the wafer W (for example, the center of the wafer W). This temperature difference causes warping at the periphery of the wafer W. Hereinafter, the warping that occurs at the periphery of the wafer W due to the temperature difference between the periphery and other areas of the wafer W will be referred to as "thermal warping".

[0051] Thermal warping occurs such that the height of the peripheral edge of the wafer W relative to the center of the wafer W gradually increases towards the radially outward direction of the wafer W. If thermal warping does not occur at the peripheral edge of the wafer W, that is, if the height of the peripheral edge of the wafer W is approximately the same as the height of the center, and the first supply unit 40 and the third supply unit 60 supply rinsing liquid to the wafer W, the rinsing liquid will scatter approximately horizontally from the peripheral edge of the wafer W. Since the rinsing liquid that scatters approximately horizontally from the peripheral edge of the wafer W lands on the inner surface of the outer cup 80 in a region lower than the wafer W (hereinafter referred to as the "lower region," an example of the second region), it is difficult to clean the region higher than the wafer W (hereinafter referred to as the "upper region," an example of the first region). In other words, it is difficult to clean the outer cup 80 over a wide area.

[0052] Therefore, in the processing unit 16 according to this embodiment, rinsing liquid is supplied to the rotating wafer W from the first supply unit 40 and the third supply unit 60 to cause thermal warping at the periphery of the wafer W, and the upper area of ​​the outer cup 80 is cleaned by the rinsing liquid scattered from the periphery.

[0053] Thus, in the first cleaning process, by supplying rinsing liquid to the wafer W from the first supply unit 40 and the third supply unit 60 while generating thermal warping at the periphery of the wafer W, the rinsing liquid can be scattered diagonally upward from the periphery of the wafer W. The rinsing liquid scattered diagonally upward from the periphery of the wafer W lands on the upper region of the outer cup 80, thus cleaning the upper region of the outer cup 80. As a result, according to the processing unit 16 of this embodiment, the outer cup 80 can be cleaned over a wide area including the upper region of the outer cup 80 without using a specially shaped cleaning substrate.

[0054] Next, the processing unit 16 performs a second cleaning process (step S104). The processing unit 16 supplies rinsing liquid from the first supply unit 40 to the rotating wafer W. Specifically, the processing unit 16 moves the first nozzle 41 from the first processing position to the second processing position, and then supplies rinsing liquid from the first supply unit 40 to a position corresponding to the center of the wafer W. When the rinsing liquid is supplied to the center of the wafer W, heat is less likely to be lost from the periphery of the wafer W, so the temperature difference between the periphery of the wafer W and the rest of the wafer W is reduced, and thermal warping does not occur at the periphery of the wafer W. When the first supply unit 40 supplies rinsing liquid to the wafer W while there is no thermal warping at the periphery of the wafer W, that is, when the height of the periphery of the wafer W is approximately the same as the height of the center, the rinsing liquid is scattered almost horizontally from the periphery of the wafer W.

[0055] Thus, in the second cleaning process, the rinsing liquid is supplied to the wafer W from the first supply unit 40 without causing thermal warping at the periphery of the wafer W, allowing the rinsing liquid to be scattered substantially horizontally from the periphery of the wafer W. The rinsing liquid scattered substantially horizontally from the periphery of the wafer W lands on the area below the outer cup 80, thus cleaning the area below the outer cup 80. As a result, according to the processing unit 16 of this embodiment, the outer cup 80 can be cleaned over a wide area including the area below the outer cup 80.

[0056] Next, the processing unit 16 performs a drying process (step S105). During the drying process, the processing unit 16 increases the rotation speed of the wafer W. This causes any remaining liquid on the wafer W to be shaken off by centrifugal force, thus drying the wafer W.

[0057] Next, the processing unit 16 performs the unloading process (step S106). In the unloading process, the wafer W is unloaded from the processing container 10 by the substrate transport device 17 (see Figure 1). The wafer W unloaded from the processing container 10 is then placed in the carrier C by the substrate transport device 13.

[0058] Note that either the first cleaning process (step S103) or the second cleaning process (step S104) described above may be omitted.

[0059] Furthermore, the order of the first cleaning process (step S103) and the second cleaning process (step S104) described above can be interchanged. That is, the upper region of the outer cup 80 may be cleaned after the lower region of the outer cup 80 has been cleaned.

[0060] Next, specific examples of the first and second cleaning processes will be described. Here, an example of performing the first cleaning process after the second cleaning process will be described with reference to Figures 5 to 7. Figure 5 is a timing chart showing an example of the operation of each part in the first and second cleaning processes according to the embodiment. Figures 6 and 7 are diagrams showing examples of the operation of the first supply unit 40 and the third supply unit 60 in the first and second cleaning processes according to the embodiment.

[0061] Figure 5 also shows timing charts for the heating fluid flow rate, rinsing fluid flow rate (periphery), rinsing fluid flow rate (center), and wafer rotation speed. The heating fluid flow rate indicates the flow rate of heated fluid supplied from the heating mechanism 30 to the back surface of the wafer W. The rinsing fluid flow rate (periphery) indicates the flow rate of rinsing fluid supplied to the periphery of the wafer W from the first supply unit 40 and the third supply unit 60. The rinsing fluid flow rate (center) indicates the flow rate of rinsing fluid supplied to the center of the wafer W from the first supply unit 40. The wafer rotation speed indicates the rotation speed of the wafer W rotated by the holding unit 20.

[0062] As shown in Figure 5, the processing unit 16 first rotates the wafer W at a rotational speed R1 using the holding unit 20 at time t1. The processing unit 16 also sets the flow rate of the heated fluid supplied by the heating mechanism 30 to flow rate H1. The flow rate H1 of the heated fluid in the second cleaning process is less than the flow rate H2 of the heated fluid in the first cleaning process.

[0063] Furthermore, the processing unit 16 moves the first nozzle 41 of the first supply unit 40 from the retracted position to the second processing position. This allows the processing unit 16 to move the supply position of the rinsing liquid to the wafer W to a position corresponding to the center of the wafer W. The processing unit 16 starts supplying the rinsing liquid from the first nozzle 41 at time 0. The processing unit 16 increases the supply flow rate of the rinsing liquid from 0 to flow rate F1 from time 0 to time t1. This allows the processing unit 16 to set the flow rate of the rinsing liquid supplied to the center of the wafer W in the second cleaning process to a flow rate F1 (an example of a second flow rate) that is greater than the flow rate F2 (an example of a first flow rate) in the first cleaning process.

[0064] Next, at time t2, the processing unit 16 increases the rotation speed of the wafer W from rotation speed R1 to rotation speed R2. Then, at time t3, the processing unit 16 increases the rotation speed of the wafer W from rotation speed R2 to rotation speed R3. The rotation speeds R1 to R3 of the wafer W in the second cleaning process are lower than the rotation speed R4 of the wafer W in the first cleaning process. In other words, in the second cleaning process, the processing unit 16 rotates the wafer W at rotation speeds R1 to R3 (an example of the second rotation speed) which are lower than rotation speed R4 (an example of the first rotation speed).

[0065] In this way, during the second cleaning process, the processing unit 16 supplies rinsing liquid from the first nozzle 41 of the first supply unit 40 to the central part of the rotating wafer W (see Figure 6). When rinsing liquid is supplied to the central part of the wafer W, heat is less likely to be lost from the peripheral part of the wafer W, thus reducing the temperature difference between the peripheral part of the wafer W and the rest of the wafer W, and preventing thermal warping from occurring at the peripheral part of the wafer W. When the first supply unit 40 supplies rinsing liquid to the wafer W while there is no thermal warping at the peripheral part of the wafer W, that is, when the height of the peripheral part of the wafer W is approximately the same as the height of the central part, the rinsing liquid is scattered almost horizontally from the peripheral part of the wafer W. The rinsing liquid scattered almost horizontally from the peripheral part of the wafer W lands on the lower region 80b of the outer cup 80, thus cleaning the lower region 80b of the outer cup 80.

[0066] Furthermore, the processing unit 16 can clean a wide area from the bottom to the top of the lower region 80b of the outer cup 80 by gradually increasing the rotation speed of the wafer W from rotation speed R1 to R3.

[0067] Next, at time t4, the processing unit 16 increases the rotation speed of the wafer W from rotation speed R3 to rotation speed R4. That is, in the first cleaning process, the processing unit 16 rotates the wafer W at rotation speed R4. The processing unit 16 also increases the flow rate of the heated fluid supplied by the heating mechanism 30 from flow rate H1 to flow rate H2. As a result, the temperature of the wafer W heated by the heating mechanism 30 rises. At time t4, the processing unit 16 also terminates the supply of rinsing liquid from the first nozzle 41.

[0068] Next, during the period from time t4 to time t5, the processing unit 16 moves the first nozzle 41 of the first supply unit 40 from the second processing position to the first processing position, and moves the back nozzle 61 of the third supply unit 60 from the retracted position to the fourth processing position. This allows the processing unit 16 to move the supply position of the rinsing liquid to the wafer W to a position closer to the periphery of the wafer W than to the center of the wafer W. At time t5, the processing unit 16 starts supplying the rinsing liquid from the first nozzle 41 and the back nozzle 61. From time t5 to time t6, the processing unit 16 increases the supply flow rate of the rinsing liquid from 0 to flow rate F2. This allows the processing unit 16 to set the flow rate of the rinsing liquid supplied to the periphery of the wafer W to flow rate F2 during the first cleaning process.

[0069] In this way, during the first cleaning process, the processing unit 16 supplies rinsing liquid from the first nozzle 41 of the first supply unit 40 and the back nozzle 61 of the third supply unit 60 to a position closer to the periphery of the wafer W than to the center of the rotating wafer W (see Figure 7). When rinsing liquid at a lower temperature than the wafer W is supplied to the periphery of the wafer W, heat is removed from the periphery of the wafer W, causing a temperature difference between the periphery and other areas (for example, the center of the wafer W), resulting in thermal warping. By supplying rinsing liquid to the wafer W from the first supply unit 40 and the third supply unit 60 while generating thermal warping at the periphery of the wafer W, the processing unit 16 can cause the rinsing liquid to scatter diagonally upward from the periphery of the wafer W. The rinsing liquid scattered diagonally upward from the periphery of the wafer W lands on the upper region 80a of the outer cup 80, thus cleaning the upper region 80a of the outer cup 80. This allows the outer cup 80 to be cleaned over a wide area including the upper region 80a. However, even when a rinsing solution at the same temperature as the wafer W is supplied to the peripheral edge of the wafer W, thermal warping due to the heat of vaporization of the rinsing solution will occur at the peripheral edge of the wafer W.

[0070] In this example, the processing unit 16 may set the temperature of the heating mechanism 30 to a first temperature in the first cleaning process, and set the temperature of the heating mechanism 30 to a second temperature lower than the first temperature in the second cleaning process. In other words, the temperature of the heating mechanism 30 in the first cleaning process may be higher than the temperature of the heating mechanism 30 in the second cleaning process. This increases the temperature of the wafer W heated by the heating mechanism 30 in the first cleaning process, thereby increasing the temperature difference between the peripheral edge of the wafer W and the rest of the wafer, making it easier to cause thermal warping.

[0071] Furthermore, the processing unit 16 may adjust the amount of thermal warping in the first cleaning process by changing at least one of the set temperature of the heating mechanism 30, the supply position of the rinse liquid, the supply flow rate of the rinse liquid, and the rotation speed of the wafer W. This makes it possible to clean a wide area from below to above the upper region 80a of the outer cup 80.

[0072] Here, the adjustment of the amount of warpage due to thermal warping will be described with reference to FIGS. 8 to 10. As a result of intensive research, the inventor of the present application has found that the amount of warpage due to thermal warping can be adjusted by changing at least one of the set temperature of the heating mechanism 30, the supply position of the rinse liquid, the supply flow rate of the rinse liquid, and the rotation speed of the wafer W.

[0073] FIG. 8 is a diagram for explaining an example of adjusting the amount of warpage due to thermal warping by the heater temperature. In FIG. 8, the horizontal axis represents the heater temperature (that is, the set temperature of the heating mechanism 30), and the vertical axis represents the amount of warpage of the peripheral portion of the wafer W due to thermal warping. The amount of warpage due to thermal warping is represented by the height of the edge of the wafer W with respect to the central portion of the wafer W. In the evaluation of FIG. 8, as evaluation conditions other than the heater temperature, the rotation speed of the wafer W: 2400 rpm and the supply position of the rinse liquid: 5 mm from the end face of the wafer W were used.

[0074] As shown in FIG. 8, the amount of warpage due to thermal warping increased as the set temperature of the heating mechanism 30 increased. This is presumably because the temperature of the wafer W increased by increasing the set temperature of the heating mechanism 30, and the temperature difference between the peripheral portion of the wafer W and the other regions increased.

[0075] FIG. 9 is a diagram for explaining an example of adjusting the amount of warpage due to thermal warping by the supply position of the rinse liquid. In FIG. 9, the horizontal axis represents the supply position of the rinse liquid supplied to the wafer W from the first supply unit 40 and the third supply unit 60, and the vertical axis represents the amount of warpage of the peripheral portion of the wafer W due to thermal warping. The supply position of the rinse liquid with respect to the wafer W is represented by the distance from the end face of the wafer W along the radial direction of the wafer W. In the evaluation of FIG. 9, as evaluation conditions other than the supply position of the rinse liquid, the rotation speed of the wafer W: 2400 rpm and the heater temperature: T1 or T2 (<T1) were used.

[0076] As shown in FIG. 9, the amount of warpage due to thermal warpage increased as the supply position of the rinse liquid moved away from the end face of the wafer W. This is presumably because as the supply position of the rinse liquid is moved away from the end face of the wafer W, the area of the liquid film covering the peripheral portion of the wafer W increases and the amount of heat taken away from the peripheral portion of the wafer W increases, resulting in an increase in the temperature difference between the peripheral portion of the wafer W and the other regions.

[0077] FIG. 10 is a diagram for explaining an example of adjusting the amount of warpage due to thermal warpage according to the rotational speed of the wafer W. In FIG. 10, the horizontal axis represents the rotational speed of the wafer W, and the vertical axis represents the amount of warpage due to thermal warpage at the peripheral portion of the wafer W. In the evaluation of FIG. 10, as evaluation conditions other than the rotational speed of the wafer W, a supply position of the rinse liquid: 5 mm from the end face of the wafer W, and heater temperatures: T1 or T2 (<T1) were used.

[0078] As shown in FIG. 10, the amount of warpage due to thermal warpage increased as the rotational speed of the wafer W approached a predetermined rotational speed. This is presumably because when the rotational speed of the wafer W is near the predetermined rotational speed, the peripheral portion of the wafer W is appropriately covered by the liquid film and heat is taken away from the peripheral portion of the wafer W, resulting in a temperature difference between the peripheral portion of the wafer W and the other regions. Also, the amount of warpage due to thermal warpage decreased as the rotational speed of the wafer W increased from the predetermined rotational speed. This is presumably because when the rotational speed of the wafer W exceeds the predetermined rotational speed, the centrifugal force acting on the wafer W increases and the wafer W is stretched in the horizontal direction.

[0079] Thus, by changing at least one of the set temperature of the heating mechanism 30, the supply position of the rinse liquid, and the rotational speed of the wafer W, the amount of warpage due to thermal warpage can be adjusted.

[0080] The inventors also measured the amount of thermal warping when the supply flow rate of the rinse solution was changed. As a result, it was found that the amount of thermal warping changes with changes in the supply flow rate of the rinse solution. Therefore, the amount of thermal warping can be adjusted by changing the supply flow rate of the rinse solution. A change in the supply flow rate of the rinse solution can be achieved, for example, by individually changing the supply flow rates of the rinse solution supplied from the first nozzle 41 of the first supply unit 40 and the back nozzle 61 of the third supply unit 60. Alternatively, a change in the supply flow rate of the rinse solution can also be achieved by changing the number of nozzles used to supply the rinse solution to the peripheral edge of the wafer W. For example, the supply flow rate of the rinse solution can be increased by supplying the rinse solution to the peripheral edge of the wafer W from the second nozzle 51 of the second supply unit 50 (see Figure 2) in addition to the first nozzle 41 of the first supply unit 40 and the back nozzle 61 of the third supply unit 60.

[0081] Furthermore, the inventors of the present invention also measured the amount of thermal warping when the flow rate of the heated fluid supplied from the heating mechanism 30 to the back surface of the wafer W was changed. As a result, it was found that the amount of thermal warping changes as the flow rate of the heated fluid changes. Therefore, the amount of thermal warping can be adjusted by changing the flow rate of the heated fluid.

[0082] Furthermore, the inventors of the present invention also measured the amount of thermal warping when the supply position of the heated fluid supplied from the heating mechanism 30 to the back surface of the wafer W was changed. As a result, it was found that the amount of thermal warping changes as the supply position of the heated fluid changes. Therefore, the amount of thermal warping can be adjusted by changing the supply position of the heated fluid. Changing the supply position of the heated fluid can be achieved, for example, by switching between discharging fluid from the inner discharge port and discharging fluid from the outer discharge port when the heating mechanism 30 has a plurality of discharge ports arranged concentrically.

[0083] (Modification of Embodiment 1) Figure 11 is a schematic diagram showing the configuration of a processing unit 16 according to a modified example 1 of the embodiment. As shown in Figure 11, the processing unit 16 may include a first monitoring unit 90. The first monitoring unit 90 monitors the cleanliness of the upper and lower regions of the outer cup 80. The cleanliness is monitored, for example, by measuring the ratio of the area occupied by deposits attached to the outer cup 80 in the gap between the outer cup 80 and the wafer W when the processing unit 16 is viewed from above, and by measuring the contrast of the inner surface of the outer cup 80.

[0084] The first monitoring unit 90 may be, for example, an imaging unit that images the upper and lower regions of the outer cup 80. The imaging unit may be, for example, a CCD (Charge Coupled Device) camera. The images of the upper and lower regions of the outer cup 80 captured by the first monitoring unit 90 as an imaging unit are output to the control unit 18 as monitoring results.

[0085] The control unit 18 can determine which of the first and second cleaning processes to be performed by comparing the cleanliness of the upper and lower regions of the outer cup 80 with a threshold value based on the image acquired from the first monitor unit 90.

[0086] Figure 12 is a flowchart showing the procedure for the cleaning content determination process performed by the processing unit 16 according to the modified embodiment 1.

[0087] As shown in Figure 12, the control unit 18 obtains the cleanliness monitoring results of the upper and lower regions of the outer cup 80 from the first monitoring unit 90 (step S201).

[0088] Next, the control unit 18 compares the cleanliness of the upper and lower regions of the outer cup 80 with a threshold value. If the cleanliness of the upper and lower regions of the outer cup 80 falls below the threshold value (step S202; Yes, step S203; Yes), the control unit 18 decides to execute both the first and second washing processes (step S204).

[0089] Furthermore, if the comparison results show that only the cleanliness of the upper region of the outer cup 80 falls below the threshold (step S202; Yes, step S203; No), the control unit 18 decides to perform only the first washing process (step S205).

[0090] Furthermore, if the comparison results show that only the cleanliness of the lower region of the outer cup 80 falls below the threshold (step S202; No, step S206; Yes), the control unit 18 decides to perform only the second cleaning process (step S207).

[0091] Furthermore, if the comparison results show that the cleanliness of the upper and lower regions of the outer cup 80 does not fall below a threshold (step S202; No, step S206; No), the control unit 18 decides not to perform either the first or second cleaning process and terminates the process.

[0092] (Modified embodiment 2) Figure 13 is a schematic diagram showing the configuration of a processing unit 16 according to a modified example 2 of the embodiment. As shown in Figure 13, the processing unit 16 may include a second monitoring unit 100. The second monitoring unit 100 monitors the hydrophilicity (oxidation degree) of the wafer W surface. Monitoring of hydrophilicity (oxidation degree) is achieved, for example, by measuring the size of the droplets of rinsing liquid scattered from the periphery of the wafer W when rinsing liquid is supplied to the periphery of the wafer W.

[0093] The second monitoring unit 100 may be, for example, an imaging unit that images droplets of rinse liquid scattered from the periphery of the wafer W. The imaging unit may be, for example, a CCD camera. The image of the rinse liquid droplets captured by the second monitoring unit 100 as an imaging unit is output to the control unit 18 as a monitoring result.

[0094] Incidentally, when the hydrophilicity (degree of oxidation) of the wafer W surface decreases, when rinsing solution is supplied to the periphery of the wafer W, the periphery of the wafer W becomes less likely to be covered by a liquid film of the rinsing solution. As a result, heat is less likely to be lost from the periphery of the wafer W, the temperature difference between the periphery of the wafer W and the rest of the wafer W is reduced, and thermal warping is less likely to occur at the periphery of the wafer W. Consequently, it becomes difficult to perform the first cleaning process using thermal warping.

[0095] Therefore, in the modified example 2, the control unit 18 determines whether or not to perform a process to make the surface of the wafer W hydrophilic by comparing the hydrophilicity of the surface of the wafer W with a threshold value based on the image acquired from the second monitor unit 100.

[0096] Figure 14 is a flowchart showing the procedure for the hydrophilization treatment performed by the treatment unit 16 according to the modified embodiment 2.

[0097] As shown in Figure 14, the control unit 18 obtains the monitoring result of the hydrophilicity (oxidation degree) of the wafer W surface from the second monitoring unit 100 (step S301).

[0098] Next, the control unit 18 determines whether the hydrophilicity (oxidation degree) of the wafer W surface is below a threshold (step S302). If the control unit 18 determines that the hydrophilicity (oxidation degree) of the wafer W surface is below a threshold (step S302; Yes), it decides to perform a process to make the wafer W surface hydrophilic (hereinafter referred to as "hydrophilization process"). Then, the control unit 18 performs the hydrophilization process (step S303).

[0099] For example, the control unit 18 hydrophilizes (oxidizes) the surface of the wafer W by supplying a chemical solution containing an oxidizing agent to the rotating wafer W from the first supply unit 40. The chemical solution containing the oxidizing agent may be, for example, a liquid that does not dissolve the film formed on the surface of the wafer W or the wafer W itself. Such a chemical solution may be at least one liquid selected from SPM (a mixture of sulfuric acid, hydrogen peroxide, and water), SC1 (a mixture of ammonia, hydrogen peroxide, and water), SC2 (a mixture of hydrochloric acid, hydrogen peroxide, and water), and hydrogen peroxide solution.

[0100] On the other hand, if the hydrophilicity (oxidation degree) of the wafer W surface in step S302 is not below the threshold (step S302; No), the control unit 18 decides not to perform the hydrophilization treatment.

[0101] In step S303 of Figure 14, the control unit 18 is shown as an example of hydrophilizing (oxidizing) the surface of the wafer W using a chemical solution containing an oxidizing agent. However, the hydrophilization treatment may be performed by other methods. For example, the control unit 18 may hydrophilize (oxidize) the surface of the wafer W by heating the wafer W in an oxygen atmosphere.

[0102] (Modification of Embodiment 3) Incidentally, when a series of processes are performed on a wafer W using a chemical solution discharged from a nozzle, the nozzle itself may become contaminated due to splashing from the wafer W. Therefore, in the processing unit 16 according to the modified embodiment 3, the nozzle is cleaned together with the upper region 80a of the outer cup 80 during the first cleaning process.

[0103] Figure 15 shows an example of the operation of the first supply unit 40, the second supply unit 50, and the third supply unit 60 in the first cleaning process according to a modified example of the embodiment 3.

[0104] In Modification 3, as shown in Figure 15, the control unit 18 supplies rinsing liquid from the first nozzle 41 of the first supply unit 40 and the back nozzle 61 of the third supply unit 60 to a position closer to the periphery of the wafer W than to the center of the rotating wafer W. When rinsing liquid at a lower temperature than the wafer W is supplied to the periphery of the wafer W, heat is removed from the periphery of the wafer W, creating a temperature difference between the periphery and other areas (for example, the center of the wafer W), causing thermal warping. The processing unit 16 supplies rinsing liquid to the wafer W from the first supply unit 40 and the third supply unit 60 while causing thermal warping at the periphery of the wafer W, thereby causing the rinsing liquid to be scattered diagonally upward from the periphery of the wafer W. The rinsing liquid that splashes diagonally upward from the periphery of the wafer W lands on the upper region 80a of the outer cup 80, and also on the second nozzle 51 of the second supply unit 50, which is located in a retracted position, for example. This allows the upper region 80a and the second nozzle 51 to be cleaned. As a result, the outer cup 80 can be cleaned over a wide area including the upper region 80a, and the second nozzle 51 can also be cleaned.

[0105] As described above, the substrate processing apparatus according to the embodiment (for example, processing unit 16) comprises a holding section (for example, holding section 20), a heating mechanism (for example, heating mechanism 30), a cleaning liquid supply section (for example, first supply section 40, second supply section 50, and third supply section 60), a liquid receiving container (for example, outer cup 80), and a control unit (for example, control unit 18). The holding section rotatably holds the substrate (for example, wafer W). The heating mechanism heats the substrate held in the holding section. The cleaning liquid supply section supplies cleaning liquid (for example, rinsing liquid) to the substrate. The liquid receiving container is arranged around the holding section. The control unit controls each section. The control unit performs a heating treatment and a first cleaning treatment. The heating treatment heats the substrate held in the holding section using the heating mechanism. The first cleaning process involves supplying cleaning fluid from a cleaning fluid supply unit to a rotating substrate to cause warping at the periphery of the substrate, and cleaning the first region (for example, the upper region 80a) of the liquid receiving container with the cleaning fluid splashing from the periphery.

[0106] As a result, according to the substrate processing apparatus of this embodiment, the liquid receiving container can be cleaned over a wide area.

[0107] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. Indeed, the embodiments described above can be embodied in a variety of forms. Furthermore, the embodiments described above may be omitted, replaced, or modified in various ways without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0108] 1. Substrate Processing System 4. Control device 16 Processing Units 17. Substrate transport device 18 Control Unit 19 Memory section 20 Holding part 21 Vacuum Chuck 22 Shaft section 23 Drive unit 30 Heating mechanism 35b Discharge port 40 1st supply section 41. Nozzle No. 1 42 Arms 43 Moving mechanism 50 2nd supply section 51. Second nozzle 52 Arms 53 Moving mechanism 60 Third supply section 61. Backside nozzle 80 Outer cup 80a upper area 80b lower area 81 Drain port 90 First Monitor Section 100 Second Monitor Section W wafer

Claims

1. A holding part that rotatably holds the substrate, A heating mechanism for heating the substrate held in the holding part, A cleaning liquid supply unit that supplies cleaning liquid to the substrate, A liquid receiving container arranged around the aforementioned holding portion, Control unit that controls each part Equipped with, The control unit, A heating process in which the substrate held in the holding part is heated using the heating mechanism, A first cleaning process in which, while the substrate is heated, the cleaning liquid is supplied from the cleaning liquid supply unit to the rotating substrate to cause warping at the periphery of the substrate, and the cleaning liquid splashing from the periphery cleans the first area of ​​the liquid receiving container. A substrate processing device that performs this operation.

2. The control unit, The substrate processing apparatus according to claim 1, wherein in the first cleaning process, the cleaning liquid is supplied from the cleaning liquid supply unit to a position closer to the peripheral edge of the substrate than to the central part of the substrate, thereby causing the curvature at the peripheral edge of the substrate.

3. The control unit, The substrate processing apparatus according to claim 1, wherein in the first cleaning process, the amount of warping is adjusted by changing at least one of the set temperature of the heating mechanism, the supply position of the cleaning liquid, the supply flow rate of the cleaning liquid, and the rotation speed of the substrate.

4. The control unit, The substrate processing apparatus according to claim 1, further comprising supplying the cleaning liquid from the cleaning liquid supply unit to the rotating substrate, thereby performing a second cleaning process in which the cleaning liquid cleans a second region of the liquid receiving container that is lower in height than the first region, without causing the warping of the peripheral edge of the substrate.

5. The cleaning fluid supply unit includes a nozzle for supplying the cleaning fluid to the substrate and a moving mechanism for moving the nozzle. The control unit, The substrate processing apparatus according to claim 4, wherein in the first cleaning process, the supply position of the cleaning liquid is moved to a position closer to the peripheral edge of the substrate than to the center of the substrate, and in the second cleaning process, the supply position of the cleaning liquid is moved to a position corresponding to the center of the substrate.

6. The control unit, The substrate processing apparatus according to claim 5, wherein in the first cleaning process, the setting temperature of the heating mechanism is set to a first temperature, and in the second cleaning process, the setting temperature of the heating mechanism is set to a second temperature lower than the first temperature.

7. The control unit, The substrate processing apparatus according to claim 4, wherein in the first cleaning process, the supply flow rate of the cleaning solution is set to a first flow rate, and in the second cleaning process, the supply flow rate of the cleaning solution is set to a second flow rate that is greater than the first flow rate.

8. The control unit, The substrate processing apparatus according to claim 4, wherein in the first cleaning process, the substrate is rotated at a first rotational speed, and in the second cleaning process, the substrate is rotated at a second rotational speed lower than the first rotational speed.

9. The substrate processing apparatus according to claim 1, wherein the heating mechanism includes a plurality of outlets capable of discharging a fluid and a heater for heating the fluid, and the substrate is heated by supplying the heated fluid to the substrate from the plurality of outlets.

10. The liquid receiving container further comprises a first monitoring unit for monitoring the cleanliness of the first and second regions, The control unit, The substrate processing apparatus according to claim 4, further comprising: a first determination process that determines, based on the monitoring results from the first monitoring unit, one or both of the first cleaning process and the second cleaning process to be performed.

11. The substrate further comprises a second monitoring unit for monitoring the hydrophilicity of the substrate surface, The control unit, The substrate processing apparatus according to claim 1, further comprising a second determination process that determines whether or not to perform a process to make the surface of the substrate hydrophilic based on the monitoring results from the second monitoring unit.

12. The system comprises a plurality of cleaning fluid supply units, including at least a first cleaning fluid supply unit and a second cleaning fluid supply unit. The first cleaning fluid supply unit has a first nozzle for supplying cleaning fluid to the substrate, The second cleaning fluid supply unit has a second nozzle for supplying cleaning fluid to the substrate, The control unit, The substrate processing apparatus according to claim 1, wherein in the first cleaning process, the cleaning liquid is supplied from the first nozzle to the rotating substrate to cause warping at the peripheral edge of the substrate, and the cleaning liquid scattered from the peripheral edge cleans the second nozzle together with the first region.

13. The substrate is held using a holding part that rotatably holds the substrate, The held substrate is heated using a heating mechanism, With the substrate heated, a cleaning liquid is supplied to the rotating substrate from a cleaning liquid supply unit, causing the peripheral edge of the substrate to warp, and the cleaning liquid splashing from the peripheral edge cleans the first region of the liquid receiving container arranged around the holding unit. A method for cleaning a liquid receiving container, including [details omitted].

14. Cleaning the first region is A method for cleaning a liquid receiving container according to claim 13, wherein the cleaning liquid is supplied from the cleaning liquid supply unit to a location radially outward of the substrate from the center position of the substrate, thereby causing the curvature at the peripheral edge of the substrate.

15. Cleaning the first region is A method for cleaning a liquid receiving container according to claim 13, wherein the amount of warping is adjusted by changing at least one of the set temperature of the heating mechanism, the supply position of the cleaning liquid, the supply flow rate of the cleaning liquid, and the rotation speed of the substrate.

16. The cleaning liquid is supplied from the cleaning liquid supply unit to the rotating substrate, and the second region of the liquid receiving container, which is lower in height than the first region, is cleaned with the cleaning liquid without causing warping at the periphery of the substrate. A method for cleaning a liquid receiving container according to claim 13, further comprising:

17. The cleaning fluid supply unit includes a nozzle for discharging the cleaning fluid onto the substrate and a moving mechanism for moving the nozzle. Cleaning the first region is The heating mechanism's set temperature is set to a first temperature, and the supply position of the cleaning solution is moved radially outward from the center position of the substrate. Cleaning the second area mentioned above is The method for cleaning a liquid receiving container according to claim 16, wherein the supply position of the cleaning liquid is moved to the center position of the substrate.

18. Cleaning the second area mentioned above is The method for cleaning a liquid receiving container according to claim 17, wherein the set temperature of the heating mechanism is set to a second temperature lower than the first temperature.

19. Cleaning the first region is The supply flow rate of the cleaning solution is set to a first flow rate, Cleaning the second area mentioned above is The method for cleaning a liquid receiving container according to claim 16, wherein the supply flow rate of the cleaning liquid is set to a second flow rate that is greater than the first flow rate.

20. Cleaning the first region is The substrate is rotated at a first rotational speed, Cleaning the second area mentioned above is The method for cleaning a liquid receiving container according to claim 16, wherein the substrate is rotated at a second rotational speed lower than the first rotational speed.

Images