Substrate processing method and substrate processing device

Abstract

A substrate processing method is a method for processing a substrate by supplying a chemical solution to a surface of a substrate on which a pattern is formed, the substrate processing method comprising: a substrate holding step for holding the substrate; a chemical solution supplying step for supplying the chemical solution to at least the aforementioned surface of the substrate; a low-conductivity liquid supplying step for supplying a low-conductivity liquid having a lower conductivity than the chemical solution to the aforementioned surface of the substrate before the chemical solution supplying step for destaticizing the substrate; and a high-conductivity liquid supplying step for supplying a high-conductivity liquid having a lower conductivity than the chemical solution and a higher conductivity than the low-conductivity liquid to the back side of the substrate opposite to the aforementioned surface instead of the aforementioned surface of the substrate before the low-conductivity liquid supplying step for destaticizing the substrate.

Description

Technical Field

[0001] The present invention relates to a substrate processing method and a substrate processing device for processing the surface of a substrate. The substrate to be processed includes, for example, semiconductor wafers, substrates for liquid crystal display devices, substrates for FPD (Flat Panel Display) such as organic EL (electroluminescence) display devices, substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks, substrates for photomasks, ceramic substrates, substrates for solar cells, etc. Background Art

[0002] In the manufacturing process of semiconductor devices, for example, a single-chip substrate processing device that processes substrates one by one includes: a processing chamber; a rotating chuck that holds the substrate approximately horizontally in the processing chamber and rotates the substrate; and a nozzle that discharges a chemical solution onto the surface of the substrate (the surface on which a pattern (device) is formed) that is rotated by the rotating chuck.

[0003] In the substrate processing using such a substrate processing apparatus, for example, a chemical liquid is discharged from a nozzle toward, for example, the center of the rotating substrate surface. The chemical liquid supplied to the center of the substrate surface is subjected to the centrifugal force generated by the rotation of the substrate, flows toward the periphery on the substrate surface, and spreads over the entire area of ​​the substrate surface. Thus, the entire area of ​​the substrate surface is processed using the chemical liquid.

[0004] Substrates that are transported into the processing chamber may have charges accumulated on the surface of the substrate (i.e., they are charged) due to previous processes (ion implantation, dry etching). If charges are accumulated on the surface of the substrate that is transported into the processing chamber, when the chemical liquid from the nozzle lands on the substrate surface, the surface of the substrate contacts the chemical liquid and a sharp charge change occurs on the surface of the substrate, and electrostatic discharge (arc discharge) may occur at or near the landing position of the chemical liquid. As a result, there may be local defects on the surface of the substrate, such as pattern (device) destruction or pattern perforation.

[0005] Therefore, Patent Document 1 below discloses that, in order to prevent electrostatic discharge from occurring on the substrate surface when supplying the chemical solution begins, a static eliminating liquid (eg, carbonated water) having a lower conductivity than the chemical solution is supplied to the substrate surface before supplying the chemical solution begins.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: U.S. Patent Application Publication No. 2009 / 211610 Summary of the invention

[0009] Problems to be solved by the invention

[0010] However, the substrate carried into the processing chamber may be highly charged. In static elimination using carbonated water, since charge transfer is fast, when carbonated water is applied to the substrate, static discharge occurs as the substrate surface contacts the carbonated water.

[0011] In addition, in order to slowly reduce the charge of the substrate, it is also considered to supply a static-eliminating liquid (such as DIW (deionized water)) with a lower conductivity than carbonated water to the substrate surface, and then supply carbonated water to the substrate surface. However, if the charge of the substrate is high, electrostatic discharge may occur even if DIW is supplied to the substrate surface.

[0012] That is, it is necessary to suppress or prevent the occurrence of electrostatic discharge associated with supplying a chemical solution to a substrate, and also suppress or prevent the occurrence of electrostatic discharge associated with supplying a neutralizing liquid (carbonated water, DIW) to a substrate. In other words, it is necessary to suppress or prevent the occurrence of electrostatic discharge associated with supplying a liquid to a substrate.

[0013] Therefore, an object of the present invention is to provide a substrate processing method and a substrate processing apparatus capable of suppressing or preventing the occurrence of electrostatic discharge associated with supplying liquid to a substrate surface, thereby suppressing or preventing the occurrence of local defects on the substrate surface.

[0014] Means for solving problems

[0015] The present invention provides a substrate processing method, which is a method for processing a substrate by supplying a chemical solution to a surface of a substrate formed with a pattern, the substrate processing method comprising: a substrate holding step for holding the substrate; a chemical solution supplying step for supplying the chemical solution to at least the aforementioned surface of the substrate; a low-conductivity liquid supplying step for supplying a low-conductivity liquid having a lower conductivity than the aforementioned chemical solution to the aforementioned surface of the substrate before the aforementioned chemical solution supplying step for destaticizing the substrate; and a high-conductivity liquid supplying step for supplying a high-conductivity liquid having a lower conductivity than the aforementioned chemical solution and a higher conductivity than the aforementioned low-conductivity liquid to the back side of the substrate opposite to the aforementioned surface instead of the aforementioned surface of the substrate before the aforementioned low-conductivity liquid supplying step for destaticizing the substrate.

[0016] According to this method, before supplying the chemical solution to the substrate, first, a highly conductive liquid is supplied to the back side of the substrate instead of the surface of the substrate. When the substrate is charged, the charge is accumulated on the surface of the substrate (the device surface where the device is formed), so even if the highly conductive liquid is supplied to the back side of the substrate, electrostatic discharge hardly occurs on the back side of the substrate. In addition, since the conductivity of the highly conductive liquid is relatively high, the amount of charge accumulated on the substrate can be effectively reduced by supplying the highly conductive liquid to the back side of the substrate.

[0017] In addition, by supplying a highly conductive liquid to the back surface of the substrate, the electric charges that have entered the interior of the pattern on the surface of the substrate can be drawn out to the outer surface of the pattern.

[0018] Next, a low-conductivity liquid is supplied to the substrate surface. Thus, the low-conductivity liquid can be used to effectively remove the charge that escapes to the outer surface of the pattern. Since the conductive liquid is supplied to the substrate surface after the amount of charge from the substrate is reduced, the occurrence of electrostatic discharge can be effectively suppressed or prevented. Moreover, since the conductive liquid is a low-conductivity liquid with low conductivity, the occurrence of electrostatic discharge can be more effectively suppressed or prevented.

[0019] Then, the chemical liquid is supplied to at least the surface of the substrate from which the charges are sufficiently removed by the low-conductivity liquid and the high-conductivity liquid, thereby performing chemical liquid treatment. Therefore, the occurrence of electrostatic discharge accompanying the supply of chemical liquid to the substrate surface can be suppressed or prevented.

[0020] This can suppress or prevent the occurrence of electrostatic discharge associated with supplying liquid (low-conductive liquid, high-conductive liquid, chemical solution) to the substrate surface, thereby suppressing or preventing the occurrence of local defects on the substrate surface.

[0021] In one embodiment of the present invention, the substrate processing method further includes the step of supplying the low-conductivity liquid or the high-conductivity liquid to the back side of the substrate in order to remove static electricity from the substrate while performing the low-conductivity liquid supplying step.

[0022] According to this method, while supplying a low-conductivity liquid to the surface of the substrate, a low-conductivity liquid or a high-conductivity liquid is supplied to the back of the substrate. Thus, the charge accumulated on the substrate can be removed more effectively. Therefore, the occurrence of electrostatic discharge during the supply of the liquid can be more effectively suppressed or prevented.

[0023] In another embodiment of the present invention, liquid is not supplied to the surface of the substrate simultaneously with the highly conductive liquid supplying step.

[0024] If a liquid is supplied to the substrate surface while a highly conductive liquid is supplied to the substrate back surface, there is a possibility that electrostatic discharge will occur on the substrate surface due to liquid depositing on the substrate surface.

[0025] In contrast, according to this method, liquid is not supplied to the substrate surface while highly conductive liquid is supplied to the substrate back surface, thereby more effectively suppressing or preventing electrostatic discharge from occurring on the substrate surface.

[0026] In one embodiment of the present invention, the aforementioned substrate processing method also includes: a proximity position configuration process, in which, while performing the aforementioned high-conductivity liquid supply process, an opposing component having a substrate opposing surface opposing to the entire area of ​​the aforementioned surface of the substrate is configured in a proximity position so that the aforementioned substrate opposing surface is close to the aforementioned surface of the substrate.

[0027] According to this method, while the substrate facing surface of the opposing component is brought close to the substrate surface, that is, while the substrate surface is protected by the substrate facing surface of the opposing component, a highly conductive liquid is supplied to the back side of the substrate. Therefore, it is possible to effectively suppress or prevent the highly conductive liquid from flowing from the back side of the substrate to the substrate surface side, or from flowing to the substrate surface side.

[0028] In yet another embodiment of the present invention, the aforementioned substrate processing method further includes: a second high-conductivity liquid supplying process, after the aforementioned low-conductivity liquid supplying process and before the aforementioned chemical liquid supplying process, supplying the aforementioned high-conductivity liquid to at least the aforementioned surface of the substrate in order to remove static electricity from the substrate.

[0029] According to this method, a high-conductivity liquid is supplied to at least the surface of the substrate during the period from when the low-conductivity liquid is supplied to the substrate to when the chemical solution is supplied to the substrate. That is, the low-conductivity liquid is supplied to the substrate surface in the order of the high-conductivity liquid. Since the conductive liquids are supplied in the order of the low-conductivity liquid, the high-conductivity liquid, and the chemical solution, that is, in order from the one with the lower conductivity, the substrate can be effectively de-electrified while preventing electrostatic discharge caused by the low-conductivity liquid and the high-conductivity liquid, and electrostatic discharge can be effectively suppressed when the chemical solution is supplied.

[0030] In one embodiment of the present invention, the substrate holding step includes a step of holding the substrate by bringing a conductive portion formed of a conductive material into contact with a peripheral portion of the substrate.

[0031] According to this method, static electricity can be preferably removed from the substrate via the low-conductive liquid or the high-conductive liquid.

[0032] In addition, the low-conductive liquid may include deionized water, and the high-conductive liquid may include a liquid containing ions.

[0033] The present invention provides a substrate processing device, which includes: a substrate holding unit for holding a substrate with a pattern formed on the surface; a liquid supply unit for supplying a liquid with conductivity to the surface of the substrate held by the substrate holding unit; a low-conductivity liquid supply unit for supplying a low-conductivity liquid with a conductivity lower than that of the liquid to the surface of the substrate held by the substrate holding unit; and a high-conductivity liquid supply unit for supplying a high-conductivity liquid with a conductivity lower than that of the liquid and higher than that of the low-conductivity liquid to the back side of the substrate held by the substrate holding unit on the opposite side to the surface. ; and a control device, which controls the aforementioned chemical liquid supply unit, the aforementioned low-conductivity liquid supply unit and the aforementioned high-conductivity liquid supply unit, and the aforementioned control device performs the following processes: a chemical liquid supply process, supplying the aforementioned chemical liquid to at least the aforementioned surface of the substrate; a low-conductivity liquid supply process, before the aforementioned chemical liquid supply process, supplying the aforementioned low-conductivity liquid to the aforementioned surface of the substrate in order to remove static electricity from the substrate; and a high-conductivity liquid supply process, before the aforementioned low-conductivity liquid supply process, supplying the aforementioned high-conductivity liquid not to the aforementioned surface of the substrate but to the back side of the substrate opposite to the aforementioned surface.

[0034] According to this configuration, before supplying the chemical solution to the substrate, first, a highly conductive liquid is supplied to the back side of the substrate instead of the surface of the substrate. When the substrate is charged, the charge is accumulated on the surface of the substrate (the device surface where the device is formed), so even if the highly conductive liquid is supplied to the back side of the substrate, electrostatic discharge hardly occurs on the back side of the substrate. In addition, since the conductivity of the highly conductive liquid is relatively high, the amount of charge accumulated on the substrate can be effectively reduced by supplying the highly conductive liquid to the back side of the substrate.

[0035] In addition, by supplying a highly conductive liquid to the back surface of the substrate, the electric charges that have entered the interior of the pattern on the surface of the substrate can be drawn out to the outer surface of the pattern.

[0036] Next, a low-conductivity liquid is supplied to the substrate surface. Thus, the low-conductivity liquid can be used to effectively remove the charge that escapes to the outer surface of the pattern. Since the conductive liquid is supplied to the substrate surface after the amount of charge from the substrate is reduced, the occurrence of electrostatic discharge can be effectively suppressed or prevented. Moreover, since the conductive liquid is a low-conductivity liquid with low conductivity, the occurrence of electrostatic discharge can be more effectively suppressed or prevented.

[0037] Then, the chemical liquid is supplied to at least the surface of the substrate from which the charges are sufficiently removed by the low-conductivity liquid and the high-conductivity liquid, thereby performing chemical liquid treatment. Therefore, the occurrence of electrostatic discharge accompanying the supply of chemical liquid to the substrate surface can be suppressed or prevented.

[0038] This can suppress or prevent the occurrence of electrostatic discharge associated with supplying liquid (low-conductive liquid, high-conductive liquid, chemical solution) to the substrate surface, thereby suppressing or preventing the occurrence of local defects on the substrate surface.

[0039] In one embodiment of the present invention, the substrate processing device further includes: an opposing component having a substrate opposing surface opposing to the entire area of ​​the surface of the substrate held by the substrate holding unit, and configured at a close position so that the substrate opposing surface is close to the surface of the substrate.

[0040] According to this configuration, the highly conductive liquid can be supplied to the back side of the substrate while the substrate facing surface of the opposing component is brought close to the substrate surface, that is, while the substrate surface is protected by the substrate facing surface of the opposing component. In this case, it is possible to effectively suppress or prevent the highly conductive liquid from flowing from the back side of the substrate to the substrate surface side, or from flowing to the substrate surface side.

[0041] In one embodiment of the present invention, the substrate holding means includes conductive pins formed of a conductive material, and the conductive pins are holding pins that contact and support the peripheral edge portion of the substrate.

[0042] According to this configuration, static electricity can be preferably removed from the substrate via the low-conductive liquid or the high-conductive liquid.

[0043] The foregoing and other objects, features, and effects of the present invention will become more apparent from the following description of the embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic plan view for explaining the internal layout of a substrate processing apparatus according to one embodiment of the present invention.

[0045] Figure 2 It is a schematic cross-sectional view for explaining a configuration example of a processing unit included in the substrate processing apparatus.

[0046] Figure 3 It is a block diagram for explaining the electrical structure of the main part of the above-mentioned substrate processing apparatus and a cross-sectional view showing an enlarged view of the surface of a substrate to be processed by the above-mentioned substrate processing apparatus.

[0047] Figure 4 This is a flowchart for explaining a first substrate processing example of the processing unit.

[0048] 5A to 5C are schematic diagrams showing a substrate horizontally viewed when each step of the first substrate processing example is performed.

[0049] 6A to 6C are diagrams for explaining changes in the charged state of the substrate in each step of the first substrate processing example.

[0050] 7A to 7C are diagrams for explaining the contents of the chemical solution supplying step included in the first substrate processing example.

[0051] Figure 8 It is a graph showing the test results of the static elimination test.

[0052] Fig. 9 It is a flowchart for explaining a second substrate processing example executed by the aforementioned processing unit.

[0053] Fig.10 It is a flowchart for explaining a third substrate processing example executed by the aforementioned processing unit. DETAILED DESCRIPTION

[0054] Figure 1 1 is a schematic diagram of a substrate processing device 1 according to an embodiment of the present invention as viewed from above. The substrate processing device 1 is a single-chip device that processes substrates W such as silicon wafers one by one. In this embodiment, the substrate W is a disc-shaped substrate. The substrate processing device 1 includes: a plurality of processing units 2 that process the substrate W with a processing liquid and a rinse liquid; a loading port (load port) LP for carrying a substrate container for storing a plurality of substrates W processed by the processing unit 2; an indexer robot (indexer robot) IR and a substrate transport robot CR that transport the substrate W between the loading port LP and the processing unit 2; and a control device 3 that controls the substrate processing device 1. The indexer robot IR transports the substrate W between the substrate container and the substrate transport robot CR. The substrate transport robot CR transports the substrate W between the indexer robot IR and the processing unit 2. For example, a plurality of processing units 2 have the same structure.

[0055] Figure 2 It is a schematic cross-sectional view for explaining a configuration example of the processing unit 2.

[0056] The processing unit 2 includes: a box-shaped processing chamber 4; a rotating chuck (substrate holding unit) 5 that holds a substrate W in a horizontal position in the processing chamber 4 and rotates the substrate W around a vertical rotation axis A1 passing through the center of the substrate W; an upper liquid supply unit for supplying liquid (processing liquid (chemical liquid and rinse liquid) and anti-static liquid) to the upper surface (surface (pattern forming surface) Wa of the substrate W (refer to Figure 5A, etc.)) of the substrate W held by the rotating chuck 5; a lower liquid supply unit for supplying liquid (processing liquid (chemical liquid and rinse liquid) and anti-static liquid) to the lower surface (back side Wb of the substrate W (refer to Figure 5A, etc.)) of the substrate W held by the rotating chuck 5; an opposing component 6 that is opposite to the upper surface of the substrate W held by the rotating chuck 5 and isolates the space above the substrate W from the atmosphere around it; and a cylindrical processing cup (not shown) surrounding the side of the rotating chuck 5.

[0057] Processing chamber 4 includes box-shaped partition wall 7 for accommodating spin chuck 5 and the like.

[0058] As the spin chuck 5, a clamping type chuck is used that clamps the substrate W in the horizontal direction and holds the substrate W horizontally. Specifically, the spin chuck 5 includes: a spin motor (spin unit) 12; a lower spin shaft 13 integrated with the drive shaft of the spin motor 12; and a disk-shaped spin base 14 substantially horizontally mounted on the upper end of the lower spin shaft 13. The lower spin shaft 13 is formed using a conductive material. The lower spin shaft 13 is grounded.

[0059] The rotating base 14 includes a horizontal circular upper surface 14a whose outer diameter is larger than the outer diameter of the substrate W. The rotating base 14 is formed using a conductive material. A plurality of (3 or more, for example, 6) clamping pins 15 are arranged on the peripheral portion of the upper surface 14a. The plurality of clamping pins 15 are arranged at appropriate intervals, for example, at equal intervals, on a circle corresponding to the outer peripheral shape of the substrate W in the peripheral portion of the upper surface of the rotating base 14. The clamping pins 15 are so-called conductive pins formed using a conductive material.

[0060] As described above, the lower rotating shaft 13, the rotating base 14, and the clamping pins 15 are respectively formed of conductive materials (e.g., conductive materials containing carbon, metal materials), and the lower rotating shaft 13 is grounded. Therefore, if a conductive liquid (low-conductive liquid, high-conductive liquid, and chemical solution described later) is supplied to the surface or back of the substrate W held by the rotating chuck 5, the substrate W is de-staticized via the liquid.

[0061] The facing member 6 includes a facing plate 17 and an upper surface nozzle 30 vertically penetrating the center of the facing plate 17. The facing plate 17 has a horizontally arranged circular substrate facing surface 17a facing the entire upper surface of the substrate W on its lower surface.

[0062] In this embodiment, the upper surface nozzle 30 functions as a central axis nozzle. The upper surface nozzle 30 is arranged above the spin chuck 5. The upper surface nozzle 30 is supported by the support arm 22. The upper surface nozzle 30 cannot rotate relative to the support arm 22. The upper surface nozzle 30 is raised and lowered together with the opposing plate 17 and the support arm 22. The upper surface nozzle 30 has a discharge port 30a formed at its lower end portion, which is opposite to the central portion of the upper surface of the substrate W held by the spin chuck 5.

[0063] The support arm 22 is coupled to an opposing member lifting unit 27 including an electric motor, a ball screw, etc. The opposing member lifting unit 27 lifts the opposing member 6 (opposing plate 17 and upper rotating shaft 18) and the upper surface nozzle 30 together with the support arm 22 in the vertical direction.

[0064] The facing member lifting unit 27 moves the facing plate 17 to a close position ( Figure 2 5A) and the retreat position ( Figure 2 The opposing member lifting unit 27 can hold the opposing plate 17 at the approach position (the position shown in FIG. 5A ), the upper position (the position shown in FIG. 5B and FIG. 5C ), and the retreat position. The approach position is a position where a small gap (e.g., about 0.3 mm) is provided between the substrate opposing surface 17a and the upper surface of the substrate W. The upper position is a position where the gap between the substrate opposing surface 17a and the upper surface of the substrate W is larger than the approach position and smaller than the retreat position.

[0065] The upper liquid supply unit includes an upper surface nozzle 30 , and a first upper supply unit 31 , a second upper supply unit 32 , and a third upper supply unit 33 , which respectively supply the processing liquid to the upper surface nozzle 30 .

[0066] The first upper supply unit 31 includes: an upper common pipe 35 connected to the upper surface nozzle 30 at one end; and an upper mixing valve unit UMV connected to the other end of the upper common pipe 35. The upper mixing valve unit UMV includes: an upper connecting portion 36 for supplying liquid to the upper common pipe 35; and a plurality of valves. A circulation space for circulating liquid is formed inside the upper connecting portion 36. The upper mixing valve unit UMV also includes a DIW upper pipe 37, an SC2 upper pipe 38, and an upper suction pipe 39, which are respectively connected to the upper connecting portion 36. The plurality of valves included in the upper mixing valve unit UMV include: a DIW upper valve 42 for opening and closing the DIW upper pipe 37; an SC2 upper valve 43 for opening and closing the SC2 upper pipe 38; and an upper suction valve 44 for opening and closing the upper suction pipe 39.

[0067] DIW (deionized water) is supplied from a DIW supply source to the DIW upper pipe 37. DIW is supplied to the upper surface nozzle 30 by opening the DIW upper valve while closing other valves included in the upper liquid supply unit, and DIW is discharged downward from the discharge port 30a.

[0068] SC2 (mixed liquid containing HCl and H2O2) is supplied from the SC2 supply source to the SC2 upper pipe 38. SC2 is supplied to the upper surface nozzle 30 by opening the SC2 upper valve 43 while closing other valves included in the upper liquid supply unit, thereby discharging SC2 downward from the discharge port 30a.

[0069] A suction device (not shown) is connected to the downstream end of the upper suction pipe 39. The suction device is, for example, a jet-type suction device. The jet-type suction device includes a vacuum generator and an aspirator. When the suction device is in operation, the interior of the suction device is depressurized, thereby suctioning the interior of the upper suction pipe 39, as a result of which the operation of the suction device is validated. When the operation of the suction device is validated, the interior of the upper suction pipe 39 is suctioned by opening the upper suction valve 44 while closing the other valves included in the upper liquid supply unit, and the liquid in the internal space (circulation space) of the upper connecting portion 36 and the liquid in the upper common pipe 35 are sucked by the suction device.

[0070] The second upper supply unit 32 includes: an SC1 upper pipe 46 connected to the upper surface nozzle 30; and an SC1 upper valve 47 inserted in the SC1 upper pipe 46. SC1 (a mixed liquid containing NH4OH and H2O2) from the SC1 supply source is supplied to the SC1 upper pipe 46. By opening the SC1 upper valve 47 while closing the other valves included in the upper liquid supply unit, SC1 is supplied to the upper surface nozzle 30, thereby discharging SC1 downward from the discharge port 30a.

[0071] The third upper supply unit 33 includes: an HF upper pipe 48 connected to the upper surface nozzle 30; and an HF upper valve 49 inserted in the HF upper pipe 48. HF from the HF supply source is supplied to the HF upper pipe 48. By opening the HF upper valve 49 while closing the other valves included in the upper liquid supply unit, HF is supplied to the upper surface nozzle 30, thereby discharging HF downward from the discharge port 30a. In this embodiment, HF is, for example, diluted hydrofluoric acid (DHF) that has been diluted.

[0072] In this embodiment, the upper surface nozzle 30 , the DIW upper pipe 37 , and the DIW upper valve 42 constitute a low-conductivity liquid supply unit.

[0073] The lower liquid supply unit includes: a lower surface nozzle 50 ; and a first lower supply unit 51 , a second lower supply unit 52 , and a third lower supply unit 53 , which respectively supply the processing liquid to the lower surface nozzle 50 .

[0074] The first lower supply unit 51 includes: a lower common pipe 55 connected to the lower surface nozzle 50 at one end; and a lower mixing valve unit DMV connected to the other end of the lower common pipe 55. The lower mixing valve unit DMV includes: a lower connection portion 56 for supplying liquid to the lower common pipe 55; and a plurality of valves. A circulation space for circulating liquid is formed inside the lower connection portion 56. The lower mixing valve unit DMV also includes a DIW lower pipe 57, a SC2 lower pipe 58, a CO2 underwater pipe 60, and a lower suction pipe 59, which are respectively connected to the lower connection portion 56. The multiple valves included in the lower liquid supply unit include: a DIW lower valve 62 for opening and closing the DIW lower pipe 57; a SC2 lower valve 63 for opening and closing the SC2 lower pipe 58; a CO2 underwater valve 65 for opening and closing the CO2 underwater pipe 60; and a lower suction valve 64 for opening and closing the lower suction pipe 59.

[0075] DIW from a DIW supply source is supplied to the DIW lower pipe 57. DIW is supplied to the lower surface nozzle 50 by opening the DIW lower valve 62 while closing other valves included in the lower mixing valve unit DMV, and DIW is discharged upward from the discharge port 50a.

[0076] SC2 from the SC2 supply source is supplied to the SC2 lower pipe 58. By opening the SC2 lower valve 63 while closing other valves included in the lower liquid supply unit, SC2 is supplied to the lower surface nozzle 50, and SC2 is discharged upward from the discharge port 50a.

[0077] CO2 water is supplied from a CO2 water supply source to the CO2 water underwater pipe 60. CO2 water is supplied to the lower surface nozzle 50 by opening the CO2 water underwater valve 65 while closing other valves included in the lower liquid supply unit, and the CO2 water is discharged upward from the discharge port 50a.

[0078] A suction device (not shown) is connected to the downstream end of the lower suction pipe 59. The suction device is, for example, a jet-type suction device. The jet-type suction device includes a vacuum generator and a suction device. When the suction device is in operation, the interior of the suction device is depressurized, thereby suctioning the interior of the lower suction pipe 59, with the result that the operation of the suction device is validated. When the operation of the suction device is validated, the lower suction valve 64 is opened while the other valves included in the lower liquid supply unit are closed, thereby suctioning the interior of the lower suction pipe 59, and the liquid in the internal space (circulation space) of the lower connecting portion 56 and the liquid in the lower common pipe 55 are sucked by the suction device.

[0079] The second lower supply unit 52 includes: an SC1 lower pipe 66 connected to the lower surface nozzle 50; and an SC1 lower valve 67 inserted in the SC1 lower pipe 66. SC1 from the SC1 supply source is supplied to the SC1 lower pipe 66. The SC1 lower valve 67 is opened while the other valves included in the lower liquid supply unit are closed, so that SC1 is supplied to the lower surface nozzle 50, thereby discharging SC1 upward from the discharge port 50a.

[0080] The third lower supply unit 53 includes: an HF lower pipe 68 connected to the lower surface nozzle 50; and an HF lower valve 69 inserted in the HF lower pipe 68. HF from the HF supply source is supplied to the HF lower pipe 68. By opening the HF lower valve 69 while closing the other valves included in the lower liquid supply unit, HF is supplied to the lower surface nozzle 50, thereby discharging HF upward from the discharge port 50a. In this embodiment, HF is, for example, diluted hydrofluoric acid (DHF) that has been diluted.

[0081] In this embodiment, the lower surface nozzle 50, the CO2 underwater pipe 60, and the CO2 underwater valve 65 constitute a highly conductive liquid supply unit.

[0082] Figure 3 A is a block diagram for explaining the electrical configuration of a main portion of the substrate processing apparatus 1 .

[0083] The control device 3 is configured using a microcomputer, for example. The control device 3 includes a computing unit such as a CPU, a storage unit such as a fixed memory device and a hard disk drive, and an input / output unit. The storage unit stores a program for executing the computing unit.

[0084] The control device 3 is connected to the rotary motor 12, the opposing member lifting unit 27, etc. as control objects. The control device 3 controls the operation of the rotary motor 12, the opposing member lifting unit 27, etc. according to a preset program.

[0085] In addition, the control device 3 opens and closes the DIW upper valve 42, the SC2 upper valve 43, the upper suction valve 44, the SC1 upper valve 47, the HF upper valve 49, the DIW lower valve 62, the SC2 lower valve 63, the lower suction valve 64, the CO2 underwater valve 65, the SC1 lower valve 67, and the HF lower valve 69 according to a pre-set program.

[0086] Hereinafter, a case where a substrate W having a pattern 100 formed on the surface (surface) Wa which is a pattern formation surface (device formation surface) is processed will be described.

[0087] Figure 3B is a cross-sectional view showing an enlarged surface Wa of a substrate W to be processed by the substrate processing apparatus 1. The substrate W to be processed is, for example, a silicon wafer, and a pattern 100 is formed on its pattern forming surface, that is, the surface Wa. The pattern 100 is, for example, a fine pattern. Figure 3 As shown in FIG. 1B, the pattern 100 may be a pattern in which a structure 101 having a convex shape (columnar) is arranged in rows and columns. In this case, the line width W1 of the structure 101 is set to about 3 nm to 45 nm, for example, and the gap W2 of the pattern 100 is set to about 10 nm to several μm, for example. The film thickness T of the pattern 100 is about 0.2 μm to 1.0 μm, for example. In addition, for the pattern 100, for example, the aspect ratio (the ratio of the film thickness T to the line width W1) can be about 5 to 500 (typically, about 5 to 50).

[0088] In addition, the pattern 100 may be a pattern in which a linear pattern formed by fine trenches is repeatedly arranged. In addition, the pattern 100 may be formed by providing a plurality of fine holes (voids or pores) in a thin film.

[0089] The pattern 100 includes, for example, an insulating film. In addition, the pattern 100 may include a conductor film. More specifically, the pattern 100 is formed by a stacked film formed by stacking a plurality of films, and further, may include an insulating film and a conductor film. The pattern 100 may be a pattern consisting of a single-layer film. The insulating film may be a silicon oxide film (SiO2 film) or a silicon nitride film (SiN film). In addition, the conductor film may be an amorphous silicon film into which impurities are introduced for low resistance, or may be a metal film (e.g., a TiN film).

[0090] Alternatively, the pattern 100 may be a hydrophilic film. As the hydrophilic film, a TEOS film (a type of silicon oxide film) can be exemplified.

[0091] Figure 4 5A to 5C are schematic diagrams of a substrate when each step of the first substrate processing example is performed horizontally. FIG6A to 6C are diagrams for explaining changes in the charged state of the substrate W in each step of the first substrate processing example.

[0092] Reference Figure 1 to Figure 4 The first substrate processing example is described. FIGS. 5A to 6C are described appropriately. The first substrate processing example is a cleaning process for removing foreign matter (particles) from the surface of the substrate W. The second and third substrate processing examples described later are also cleaning processes for removing foreign matter from the surface of the substrate W.

[0093] An unprocessed substrate W (e.g., a circular substrate with a diameter of 300 mm) is carried from the substrate storage C into the processing unit 2 by the indexer robot IR and the substrate transport robot CR, and is carried into the processing chamber 4, and the substrate W is placed on its surface Wa (pattern forming surface. Device forming surface. Figure 3 B, etc.) is handed over to the spin chuck 5 with the substrate W facing upward, and the spin chuck 5 holds the substrate W (substrate holding step). Figure 4 S1: Loading the substrate W). In this state, the back surface Wb of the substrate W (see FIG. 6A etc.) faces downward.

[0094] The substrate moved into the internal space of the processing chamber 4 sometimes accumulates charges (i.e., is charged) on the substrate W due to its previous process (ion implantation, dry etching). When the substrate W is charged, as shown in FIG6A, the charges are mainly accumulated on the surface Wa of the substrate W. More specifically, the charges enter the interior of the pattern 100 on the surface Wa of the substrate W. If a chemical solution (conductive chemical solution such as SC1, SC2, etc.) is supplied to the substrate W, the surface Wa of the substrate W contacts the chemical solution and a sharp charge change occurs on the surface Wa of the substrate W, and electrostatic discharge may occur at or near the liquid landing position of the chemical solution. As a result, there may be a situation where local defects such as the pattern 100 being destroyed or the pattern 100 being punctured are generated on the surface Wa of the substrate W. Therefore, before the chemical solution supply process S5, in order to de-charge the substrate W, a high-conductivity liquid supply process S3 and a low-conductivity liquid supply process S4 are performed.

[0095] After the substrate transport robot CR retreats outside the processing unit 2, the control device 3 controls the rotation motor 12 to increase the rotation speed of the rotation base 14 to a predetermined static elimination rotation speed (approximately less than 500 rpm, for example, about 200 rpm), and maintains the static elimination rotation speed ( Figure 4 S2: The substrate W starts to rotate).

[0096] Furthermore, the control device 3 controls the facing member lifting unit 27 to lower the facing plate 17 from the retracted position, thereby arranging the facing plate 17 at the approach position as shown in FIG. 5A .

[0097] When the rotation of the substrate W reaches the static elimination rotation speed, the control device 3 performs a high-conductivity liquid supplying process ( FIG. 5A ) of supplying CO2 water as a high-conductivity liquid (liquid having a lower conductivity than the chemical solution (e.g., SC1, SC2)) to the back side Wb of the substrate W instead of the front side Wa of the substrate W. Figure 4 Since CO2 water contains ions, it has a certain degree of high conductivity. The resistivity of CO2 water supplied to the substrate W in the high-conductivity liquid supply step S3 (the lower the resistivity, the higher the conductivity) is, for example, 10 -6The range is from MΩ·cm to 20 MΩ·cm, and more specifically, from about 20 MΩ·cm to about 30 MΩ·cm.

[0098] Specifically, the control device 3 opens the CO2 water underwater valve 65. As a result, CO2 water is discharged from the discharge port 50a of the lower surface nozzle 50 toward the central portion of the back surface Wb (i.e., the lower surface) of the rotating substrate W. The CO2 water that has been deposited on the back surface Wb of the substrate W is moved toward the peripheral portion of the substrate W by the centrifugal force generated by the rotation of the substrate W. As a result, a liquid film of CO2 water covering the entire area of ​​the back surface Wb of the substrate W is formed.

[0099] Since CO2 water has a high conductivity, by supplying CO2 water as a highly conductive liquid to the back side Wb of the substrate W, the amount of charge accumulated in the pattern 100 of the substrate W can be effectively reduced. In addition, by supplying CO2 water to the back side Wb of the substrate W, the charge that has entered the inside of the pattern 100 on the surface Wa of the substrate W can be drawn out to the outer surface of the pattern 100 as shown in FIG6B. That is, by supplying CO2 water as a highly conductive liquid to the back side Wb of the substrate W, the local charge configuration on the surface Wa of the substrate W can be diffused. Since the charge is accumulated on the surface Wa (pattern 100) of the substrate W, even if CO2 water is supplied to the back side Wb of the substrate W, electrostatic discharge hardly occurs on the back side Wb of the substrate W.

[0100] In the highly conductive liquid supplying step S3 , if liquid is supplied to the surface Wa of the substrate W while CO 2 water is supplied to the back surface Wb of the substrate W, electrostatic discharge may occur on the surface Wa of the substrate W due to liquid adhesion to the surface Wa of the substrate W.

[0101] In the highly conductive liquid supplying step S3 , since liquid is not supplied to the front surface Wa of the substrate W while supplying CO 2 water to the back surface Wb of the substrate W, electrostatic discharge on the front surface Wa of the substrate W can be more effectively suppressed or prevented.

[0102] Furthermore, in the highly conductive liquid supplying step S3, while the opposing member 6 is arranged at the close position, that is, while the front surface Wa of the substrate W is protected by the substrate opposing surface 17a of the opposing member 6, CO2 water is supplied to the back surface Wb of the substrate W. Therefore, it is possible to effectively suppress or prevent the CO2 water from flowing from the back surface Wb of the substrate W to the front surface Wa side of the substrate W.

[0103] It should be noted that an inert gas pipe (omitted in the figure) may be further connected to the upper surface nozzle 30 of the opposing component 6, and an inert gas valve (omitted in the figure) may be inserted into the inert gas pipe. In this case, an inert gas (e.g., N2 gas, helium gas, argon gas, or a mixture thereof) is supplied from an inert gas supply source to the inert gas pipe. The inert gas valve is controlled by the control device 3. In this case, in the highly conductive liquid supply process S3, the control device 3 opens the inert gas valve while the opposing component 6 is arranged in a close position, thereby supplying inert gas to the upper surface nozzle 30 via the inert gas pipe, and discharging the inert gas downward from the discharge port 30a toward the central part of the surface Wa of the substrate W. Thus, a gas flow of inert gas flowing from the central part of the substrate W toward the peripheral part is formed along the upper surface of the substrate W. Therefore, it is possible to better suppress or prevent CO2 water from entering the surface Wa side of the substrate W from the back side Wb of the substrate W.

[0104] When a preset first static elimination period (eg, about 60 seconds) has passed since the start of the discharge of CO2 water, the control device 3 closes the CO2 water underwater valve 65 to stop the discharge of CO2 water from the lower surface nozzle 50. Thus, the highly conductive liquid supplying step S3 ends.

[0105] After the highly conductive liquid supply step S3 is completed, the control device 3 opens the lower suction valve 64. Thus, CO2 water is removed by suction from the interior of the lower common pipe 55 and the interior space of the lower connecting portion 56. After the CO2 water is removed, the control device 3 closes the lower suction valve 64.

[0106] Furthermore, the control device 3 controls the facing member lifting unit 27 to lift the facing plate 17 from the close position and arrange it in the upper position as shown in FIG. 5B .

[0107] Next, the control device 3 executes a low-conductivity liquid supplying step ( DIW) as a low-conductivity liquid (a liquid having a lower conductivity than the chemical solution (e.g., SC1, SC2) and the high-conductivity liquid (e.g., CO2 water)) to the front surface Wa of the substrate W and the back surface Wb of the substrate W as shown in FIG. 5B. Figure 4 Since DIW contains almost no ions, its electrical conductivity is quite low. The resistivity of DIW supplied to the substrate W in the low-conductivity liquid supplying step S4 is, for example, in the range of 10 MΩ·cm to 20 MΩ·cm, more specifically, about 18 MΩ·cm.

[0108] Specifically, the control device 3 opens the DIW upper valve 42. Thus, DIW is discharged from the discharge port 30a of the upper surface nozzle 30 toward the central part of the surface Wa (i.e., the upper surface) of the rotating substrate W. The DIW that has been deposited on the surface Wa of the substrate W is moved toward the peripheral part of the substrate W by the centrifugal force generated by the rotation of the substrate W. Thus, a liquid film of DIW covering the entire area of ​​the surface Wa of the substrate W is formed. At the same time, the control device 3 opens the DIW lower valve 62. Thus, DIW is discharged from the discharge port 50a of the lower surface nozzle 50 toward the central part of the back side Wb (i.e., the lower surface) of the rotating substrate W. Thus, a liquid film of DIW covering the entire area of ​​the back side Wb of the substrate W is formed.

[0109] As shown in FIG6C , the charges drawn to the outer surface of the pattern 100 by supplying CO2 water to the back surface Wb of the substrate W are effectively removed by supplying DIW to the surface Wa of the substrate W. In addition, since the conductive liquid (DIW) is supplied to the surface Wa of the substrate W after the amount of charges from the substrate W is reduced, the occurrence of electrostatic discharge can be effectively suppressed or prevented. Moreover, since the conductive liquid is DIW with a low conductivity, the occurrence of electrostatic discharge can be more effectively suppressed or prevented.

[0110] In addition, DIW is supplied to the back side Wb of the substrate W while DIW is supplied to the front side Wa of the substrate W. Thus, the charge accumulated on the substrate W can be removed more effectively. When a preset second charge removal period (e.g., about 60 seconds) has passed since the start of DIW discharge, the control device closes the DIW upper valve 42 and the DIW lower valve 62 to stop the discharge of DIW from the upper surface nozzle 30 and the discharge of DIW from the lower surface nozzle 50. Thus, the low-conductivity liquid supply process S4 ends.

[0111] After the low-conductive liquid supply step S4 is completed, the control device 3 opens the upper suction valve 44. Thus, DIW is removed by suction from the interior of the upper common pipe 35 and the interior space of the upper connecting portion 36. After the DIW is removed, the control device 3 closes the upper suction valve 44.

[0112] Furthermore, the control device 3 controls the rotation motor 12 to increase the rotation speed of the spin base 14 to a predetermined liquid processing rotation speed (eg, about 500 rpm), and maintains the rotation speed at the liquid processing rotation speed.

[0113] Next, the control device 3 executes a chemical liquid supplying step ( ) of supplying a chemical liquid to the surface Wa of the substrate W to process (clean) the surface Wa of the substrate W as shown in FIG. 5C . Figure 4In the liquid supplying step S5 of this embodiment, the control device 3 supplies liquid not only to the surface Wa of the substrate W but also to the back side Wb of the substrate W, thereby processing (cleaning) the back side Wb of the substrate W (simultaneous double-side processing). In the liquid supplying step S5, first, SC1 or SC2 is supplied to the surface Wa of the substrate W. SC1 and SC2 have high electrical conductivity because they contain a large amount of ions. The resistivity of SC1 supplied to the substrate W is, for example, 10 -3 The resistivity of the SC2 supplied to the substrate W is, for example, about 10 -5 About MΩ·cm.

[0114] SC1 and SC2 are liquids with higher conductivity than CO2 water. Therefore, if SC1 or SC2 is supplied to the surface Wa of the substrate W without fully removing the charge from the surface Wa of the substrate W (in a state where a large amount of charge is accumulated on the surface Wa of the substrate W), when SC1 or SC2 lands on the surface Wa of the substrate W, the surface Wa of the substrate W contacts SC1 or SC2 and a sharp charge change occurs on the surface Wa of the substrate W, and electrostatic discharge may occur at or near the landing position of the liquid on the surface Wa of the substrate W.

[0115] However, since SC1 or SC2 is supplied to the surface Wa of the substrate W after the charges are sufficiently removed by DIW and CO 2 water, electrostatic discharge does not occur when SC1 or SC2 lands on the surface Wa of the substrate W in the chemical solution supplying step S5 .

[0116] After the chemical liquid supplying step S5 is completed, the control device 3 executes a rinsing step (S6 in the figure) of supplying DIW as a rinsing liquid to the surface Wa of the substrate W to rinse the chemical liquid attached to the surface Wa of the substrate W. In the rinsing step S6 involved in this embodiment, DIW as a rinsing liquid is supplied not only to the surface Wa of the substrate W, but also to the back side Wb of the substrate W, thereby processing (cleaning) the back side Wb of the substrate W (simultaneous double-side processing).

[0117] The control device 3 opens the DIW upper valve 42 and the DIW lower valve 62, thereby supplying DIW to the front surface Wa and the back surface Wb of the substrate W. Furthermore, when a preset period has passed after the DIW upper valve 42 and the DIW lower valve 62 are opened, the control device 3 closes the DIW upper valve 42 and the DIW lower valve 62. Thus, the supply of DIW to the front surface Wa and the back surface Wb of the substrate W is stopped, and the rinsing step S6 is completed. Although DIW is used as the rinsing liquid, CO2 water may also be used as the rinsing liquid.

[0118] Thereafter, the control device 3 controls the opposing member lifting unit 27 to raise the opposing plate 17 to the retracted position.

[0119] Next, the control device 3 performs a drying process ( Figure 4 Specifically, the control device 3 increases the rotation speed of the substrate W to a predetermined spin-off speed (for example, several thousand rpm) that is greater than the liquid processing rotation speed, and rotates the substrate W at the spin-off speed. As a result, a large centrifugal force is applied to the liquid on the substrate W, and the liquid attached to the substrate W is spin-off to the periphery of the substrate W. In this way, the liquid is removed from the substrate W, and the substrate W is dried.

[0120] When a preset period of time has passed since the start of the drying step S7, the control device 3 controls the rotary motor 12 to stop the rotation of the spin chuck 5 (that is, the rotation of the substrate W). Figure 4 Thereafter, the substrate transport robot CR enters the inner space of the processing chamber 4 and carries the processed substrate W out of the processing chamber 4 ( Figure 4 The substrate W is handed over from the substrate transport robot CR to the indexer robot IR and is stored in the substrate storage unit C by the indexer robot IR.

[0121] 7A to 7C are diagrams for explaining the contents of the chemical liquid supplying step S5 included in the first substrate processing example. The chemical liquid supplying step S5 is a step of cleaning the front surface Wa and the back surface Wb of the substrate W using the chemical liquid.

[0122] Examples of the chemical solution supplying step S5 include a first chemical solution supplying step S51 , a second chemical solution supplying step S52 , and a third chemical solution supplying step S53 .

[0123] The first liquid supply process S51 includes: a SC1 supply process of supplying SC1 to the surface Wa and back side Wb of the substrate W; an intermediate rinsing process of supplying DIW (or CO2 water) as a rinsing liquid to the surface Wa and back side Wb of the substrate W after the SC1 supply process; a SC2 supply process of supplying SC2 to the surface Wa and back side Wb of the substrate W after the intermediate rinsing process; an intermediate rinsing process of supplying DIW (or CO2 water) as a rinsing liquid to the surface Wa and back side Wb of the substrate W after the SC2 supply process; and a DHF supply process of supplying DHF (diluted hydrofluoric acid) to the surface Wa and back side Wb of the substrate W after the intermediate rinsing process.

[0124] The second liquid supply process S52 includes: a SC2 supply process of supplying SC2 to the surface Wa and back side Wb of the substrate W; an intermediate rinsing process of supplying DIW (or CO2 water) as a rinsing liquid to the surface Wa and back side Wb of the substrate W after the SC2 supply process; and a SC1 supply process of supplying SC1 to the surface Wa and back side Wb of the substrate W after the intermediate rinsing process.

[0125] The third chemical solution supplying step S53 includes an SC1 supplying step of supplying SC1 to the front surface Wa and the back surface Wb of the substrate W.

[0126] In addition, when the upper mixing valve unit UMV or the lower mixing valve unit DMV is used to supply a treatment liquid (a chemical solution or a rinse liquid (DIW, CO2 water, SC2 in this embodiment)) from the upper surface nozzle 30 or the lower surface nozzle 50, after the discharge of the treatment liquid from the upper surface nozzle 30 or the lower surface nozzle 50 is completed, the corresponding upper suction valve 44 or the lower suction valve 64 is opened to remove the DIW or CO2 water from the interior of the upper common pipe 35 or the lower common pipe 55 and the internal space of the upper connecting part 36 or the lower connecting part 56.

[0127] In summary, according to this embodiment, before supplying the chemical solution (SC1 or SC2) to the substrate W, first, CO2 water is supplied to the back side Wb of the substrate W instead of the front side Wa of the substrate W. In the case where the substrate W is charged, since the charge is accumulated on the front side Wa of the substrate W, even if CO2 water is supplied to the back side Wb of the substrate W, electrostatic discharge hardly occurs on the back side Wb of the substrate W. In addition, since the conductivity of CO2 water is relatively high, the amount of charge accumulated on the substrate W can be effectively reduced by supplying CO2 water to the back side Wb of the substrate W.

[0128] In addition, by supplying CO 2 water to the back surface Wb of the substrate W, the electric charges that have entered the interior of the pattern 100 on the front surface Wa of the substrate W can be drawn out to the outer surface of the pattern 100 .

[0129] Next, DIW is supplied to the surface Wa of the substrate W. Thus, the charges drawn to the outer surface of the pattern 100 can be effectively removed by the DIW. In addition, since the conductive liquid (DIW) is supplied to the surface Wa of the substrate W after the amount of charges from the substrate W is reduced, the occurrence of electrostatic discharge can be effectively suppressed or prevented. Moreover, since the conductive liquid is DIW with a low conductivity, the occurrence of electrostatic discharge can be more effectively suppressed or prevented.

[0130] Then, the chemical solution supply step S5 is performed on at least the surface Wa of the substrate W sufficiently decharged by DIW and CO2 water. Therefore, in the chemical solution supply step S5, the occurrence of electrostatic discharge accompanying the supply of SC1 and SC2 to the surface Wa of the substrate W can be suppressed or prevented.

[0131] Thus, the occurrence of electrostatic discharge associated with the supply of liquid (DIW, CO 2 water, chemical solution) to the surface Wa of the substrate W can be suppressed or prevented, thereby suppressing or preventing the occurrence of local defects on the surface Wa of the substrate W.

[0132] Next, the static elimination test will be described.

[0133] In the static elimination test, the substrate processing methods (cleaning processes) according to the following examples and comparative examples were applied to the samples.

[0134] Embodiment: A pattern 100 is arranged on the surface Wa (refer to Figure 3 B) as a sample, a substrate W (semiconductor wafer, outer diameter 300 (mm)) is held on a spin chuck 5 (see Figure 2 ). The sample held in the rotating chuck 5 and in a rotating state is subjected to the aforementioned Figure 4 The first substrate processing example (cleaning process) is shown.

[0135] Comparative Examples 1 to 9: The pattern 100 (see Figure 3 B) as a sample, a substrate W (semiconductor wafer, outer diameter 300 (mm)) is held on a spin chuck 5 (see Figure 2 ). The sample held in the rotating chuck 5 and in a rotating state was cleaned using the processing unit 2. Figure 4 The difference of the embodiment shown is that the static elimination process ( Figure 4 The contents of the high-conductivity liquid supply process S3 and the low-conductivity liquid supply process S4).

[0136] Comparative Example 1: The step corresponding to the high-conductivity liquid supply step S3 and the step corresponding to the low-conductivity liquid supply step S4 are not performed. That is, the chemical liquid supply step S5 is performed first.

[0137] Comparative Example 2: Instead of the high-conductivity liquid supplying step S3, a step of supplying CO2 water to the surface Wa of the substrate W instead of the back surface Wb of the substrate W is performed. The step corresponding to the low-conductivity liquid supplying step S4 is not performed. That is, after supplying CO2 water to the surface Wa of the substrate W, the liquid supplying step S5 is performed.

[0138] Comparative Example 3: The high-conductivity liquid supplying step S3 was performed. The step corresponding to the low-conductivity liquid supplying step S4 was not performed. That is, the chemical liquid supplying step S5 was performed after the high-conductivity liquid supplying step S3.

[0139] Comparative Example 4: Instead of the high-conductivity liquid supplying step S3, a step of supplying CO2 water not only to the back surface Wb of the substrate W but also to the surface Wa of the substrate W is performed. The step corresponding to the low-conductivity liquid supplying step S4 is not performed. That is, after supplying CO2 water to the surface Wa of the substrate W, the liquid supplying step S5 is performed.

[0140] Comparative Example 5: The process corresponding to the high-conductivity liquid supply process S3 is not performed. First, the process corresponding to the low-conductivity liquid supply process S4 is performed. In this process, the process of supplying DIW to the front surface Wa of the substrate W instead of the back surface Wb of the substrate W is performed.

[0141] Comparative Example 6: The process corresponding to the high-conductivity liquid supply process S3 is not performed. First, the process corresponding to the low-conductivity liquid supply process S4 is performed. In this process, the process of supplying DIW to the back surface Wb of the substrate W instead of the front surface Wa of the substrate W is performed.

[0142] Comparative Example 7: The step corresponding to the high-conductivity liquid supply step S3 was not performed. First, the low-conductivity liquid supply step S4 was performed.

[0143] Comparative Example 8: Instead of the high-conductivity liquid supplying step S3, a step of supplying CO2 water not only to the back surface Wb of the substrate W but also to the front surface Wa of the substrate W is performed. After this step, the low-conductivity liquid supplying step S4 is performed.

[0144] Comparative Example 9: Instead of the high-conductivity liquid supplying step S3, a step of supplying CO2 water to the front surface Wa of the substrate W instead of the back surface Wb of the substrate W is performed. After this step, the low-conductivity liquid supplying step S4 is performed.

[0145] The test results are shown in Figure 8 In the embodiment, no electrostatic discharge occurred. In contrast, in Comparative Examples 1 to 9, traces of electrostatic discharge were observed in the central portion of the surface Wa of the substrate W. In Comparative Examples 2, 4, 8, and 9, highly conductive CO2 water was first supplied to the surface of the substrate W. It is believed that electrostatic discharge occurred with the supply of the CO2 water.

[0146] In Comparative Examples 5 and 7, DIW with low conductivity is first supplied to the surface Wa of the substrate W. The surface Wa of the substrate W (especially the charges entering the interior of the pattern 100 as shown in FIG. 6A ) is not sufficiently de-charged by the supply of DIW, so it is considered that electrostatic discharge occurs as the chemical solution is subsequently supplied to the surface Wa of the substrate W.

[0147] In Comparative Examples 1, 3, and 6, a highly conductive chemical solution is first supplied to the surface Wa of the substrate W. The surface Wa of the substrate W is not sufficiently de-charged before the chemical solution is supplied, so it is considered that static discharge occurs as the chemical solution is supplied to the surface Wa of the substrate W.

[0148] Although one embodiment of the present invention has been described above, the present invention can also be implemented in other forms.

[0149] Fig. 9 It is a flowchart for explaining a second substrate processing example executed by the processing unit 2 . Fig. 9 The second substrate processing example shown is Figure 4 The difference from the first substrate processing example shown in FIG. 1 is that a low-conductivity liquid supplying step S11 is used as the low-conductivity liquid supplying step instead of the low-conductivity liquid supplying step S4. In the low-conductivity liquid supplying step S11, DIW is not supplied to both the front surface Wa and the back surface Wb of the substrate W, but only to the front surface Wa of the substrate W.

[0150] In addition, Figure 4 In the first substrate processing example shown, in the low-conductivity liquid supplying step S4, DIW as the low-conductivity liquid may be supplied to the front surface Wa of the substrate W, and CO 2 water as the high-conductivity liquid may be supplied to the back surface Wb of the substrate W.

[0151] Fig.10 It is a flowchart for explaining a third substrate processing example executed by the processing unit 2 .

[0152] Fig.10 The third substrate processing example shown is Figure 4 The difference from the first substrate processing example shown in the above is that the following second high-conductivity liquid supply step S21 is performed: after the low-conductivity liquid supply step S4 and before the chemical liquid supply step S5, in order to remove static electricity from the substrate W, CO2 water is supplied as a high-conductivity liquid (a liquid with lower conductivity than the chemical liquid (e.g., SC1, SC2)) to at least the surface Wa (both the surface Wa and the back surface Wb (or only the surface Wa)) of the substrate W.

[0153] like Figure 2 As shown by the dotted line in FIG. 3 , the upper mixing valve unit UMV may further include a CO2 water upper pipe 40 connected to the upper connection portion 36 and a CO2 water upper valve 45 for opening and closing the CO2 water upper pipe 40. By opening the CO2 water upper valve 45 while closing other valves included in the upper liquid supply unit, CO2 water is supplied to the upper surface nozzle 30, thereby discharging the CO2 water downward from the discharge port 30a.

[0154] According to the third substrate processing example, CO2 water is supplied to at least the surface Wa of the substrate W during the period from when DIW is supplied to the substrate W to when the chemical solution is supplied to the substrate W. That is, the surface Wa of the substrate W is supplied in the order of DIW→CO2 water. Since the conductive liquid is supplied to the substrate in the order of DIW→CO2 water→chemical solution, that is, sequentially from the one with lower conductivity, the substrate W can be de-electrified well while preventing electrostatic discharge caused by DIW and CO2 water, thereby effectively suppressing electrostatic discharge during chemical solution supply.

[0155] In addition, as the chemical liquid supplying step S5, a step of using chemical liquid to treat both surfaces of the substrate W (surface Wa and back side Wb) can be listed. The chemical liquid supplying step S5 can also be a step of using chemical liquid to treat one surface of the substrate W (surface Wa or back side Wb).

[0156] In addition, although SC1 and SC2 are exemplified as the chemical liquid first supplied to the surface Wa of the substrate W in the chemical liquid supplying step S5, other chemical liquids (ozone water, SPM (a mixed liquid containing H2SO4 and H2O2), HF, etc.) may also be used.

[0157] In addition, as a combination of a high-conductivity liquid and a low-conductivity liquid, a combination of CO2 water and DIW is exemplified. In addition, examples include: a combination of NH3 water and DIW, a combination of an NH4OH aqueous solution (1:100) and DIW, a combination of an H2SO4 aqueous solution and DIW, a combination of an HCl aqueous solution (1:50. dilute hydrochloric acid) and DIW, a combination of an HF aqueous solution (1:500. dilute hydrofluoric acid) and DIW, etc.

[0158] Furthermore, although the first to third substrate processing examples illustrate examples of cleaning processing for cleaning the substrate W, the present invention may also be applied to etching processing for etching the substrate W using an etching liquid.

[0159] In addition, in the aforementioned embodiment, the substrate processing device 1 is described as a device for processing the surface of a substrate W formed of a semiconductor wafer, but the substrate processing device may also be a device for processing a substrate such as a liquid crystal display device substrate, an organic EL (electroluminescence) display device FPD (Flat Panel Display) substrate, an optical disk substrate, a magnetic disk substrate, an optical magneto-optical disk substrate, a photomask substrate, a ceramic substrate, a solar cell substrate, etc. However, the effect of the present invention can be particularly significantly exerted when the surface of the substrate W is hydrophobic.

[0160] The embodiments of the present invention have been described in detail, but these embodiments are merely specific examples used to clarify the technical content of the present invention. The present invention should not be construed as being limited to these specific examples, and the scope of the present invention is limited only by the attached claims.

[0161] This application corresponds to Japanese Patent Application No. 2018-009157 filed with the Japan Patent Office on January 23, 2018, and all disclosed contents of the application are incorporated into this application by reference.

[0162] Description of Reference Numerals

[0163] 1: Substrate processing equipment

[0164] 3: Control device

[0165] 4: Processing chamber

[0166] 5: Rotating chuck (substrate holding unit)

[0167] 30: Upper surface nozzle (low-conductivity liquid supply unit)

[0168] 37: DIW upper pipe (low conductivity liquid supply unit)

[0169] 42: DIW upper valve (low conductivity liquid supply unit)

[0170] 50: Bottom surface nozzle (highly conductive liquid supply unit)

Claims

1. A substrate processing method, which is a method of processing a substrate by supplying a chemical solution to a surface of a substrate on which a pattern is formed, The substrate processing method comprises: A substrate holding step for holding the substrate; a chemical solution supplying step of supplying the chemical solution to the surface of the substrate on which the pattern is formed; a low-conductive liquid supplying step, before the chemical liquid supplying step, in order to remove the electric charge accumulated on the outer surface of the pattern, opening a low-conductive liquid valve, supplying a low-conductive liquid having a lower conductivity than the chemical liquid from a low-conductive liquid supply source to a low-conductive liquid nozzle, thereby supplying the low-conductive liquid from the low-conductive liquid nozzle to the surface of the substrate on which the pattern is formed; as well as A high-conductivity liquid supply process, before the low-conductivity liquid supply process, in order to reduce the charge accumulated in the pattern, a high-conductivity liquid valve different from the low-conductivity liquid valve is opened, and a high-conductivity liquid with a conductivity lower than that of the chemical liquid and higher than that of the low-conductivity liquid is supplied to the high-conductivity liquid nozzle from a high-conductivity liquid supply source different from the low-conductivity liquid supply source, thereby supplying the high-conductivity liquid from the high-conductivity liquid nozzle to the back side of the substrate opposite to the surface where the pattern is not formed.

2. The substrate processing method according to claim 1, further comprising the step of supplying the low-conductivity liquid or the high-conductivity liquid to the back side of the substrate in order to remove static electricity from the substrate while performing the low-conductivity liquid supply step.

3. The substrate processing method according to claim 1 or 2, wherein: The liquid is not supplied to the surface of the substrate simultaneously with the highly conductive liquid supplying step.

4. The substrate processing method according to claim 1 or 2, further comprising: The close position configuration step is to configure a facing member having a substrate facing surface facing the entire surface of the substrate at a close position so that the substrate facing surface is close to the surface of the substrate while the highly conductive liquid supplying step is being performed.

5. The substrate processing method according to claim 1 or 2, further comprising: The second high-conductive liquid supplying step is performed after the low-conductive liquid supplying step and before the chemical liquid supplying step, and supplies the high-conductive liquid to at least the surface of the substrate in order to remove static electricity from the substrate.

6. The substrate processing method according to claim 1 or 2, wherein: The substrate holding step includes a step of holding the substrate by bringing a conductive portion formed of a conductive material into contact with a peripheral portion of the substrate.

7. The substrate processing method according to claim 1 or 2, wherein: The low-conductivity liquid includes deionized water.

8. The substrate processing method according to claim 1 or 2, wherein: The highly conductive liquid includes a liquid containing ions.

9. A substrate processing device, comprising: A substrate holding unit for holding a substrate having a pattern formed on a surface thereof; a chemical liquid supply unit for supplying a chemical liquid having conductivity to the surface of the substrate held by the substrate holding unit; a low-conductivity liquid nozzle for supplying a low-conductivity liquid having a lower conductivity than the chemical liquid to the surface of the substrate held by the substrate holding unit; a low-conductivity liquid supply source, used for supplying the low-conductivity liquid to the low-conductivity liquid nozzle; a low-conductivity liquid valve for switching supply and supply stop of the low-conductivity liquid from the low-conductivity liquid supply source to the low-conductivity liquid nozzle; a high-conductivity liquid nozzle for supplying a high-conductivity liquid having a lower conductivity than the chemical liquid and a higher conductivity than the low-conductivity liquid to a back surface of the substrate held by the substrate holding unit opposite to the surface; a high-conductivity liquid supply source different from the low-conductivity liquid supply source, the high-conductivity liquid supply source being used to supply the high-conductivity liquid to the high-conductivity liquid nozzle; a high-conductivity liquid valve different from the low-conductivity liquid valve, the high-conductivity liquid valve switching supply and supply stop of the high-conductivity liquid from the high-conductivity liquid supply source to the high-conductivity liquid nozzle; and a control device for controlling the liquid medicine supply unit, the low-conductivity liquid valve and the high-conductivity liquid valve, The control device performs the following steps: a chemical solution supplying step of supplying the chemical solution to the surface of the substrate on which the pattern is formed; a low-conductive liquid supplying step, before the liquid supplying step, in order to remove the electric charge accumulated on the outer surface of the pattern, opening the low-conductive liquid valve and supplying the low-conductive liquid from the low-conductive liquid nozzle to the surface of the substrate on which the pattern is formed; as well as A high-conductivity liquid supplying process is performed before the low-conductivity liquid supplying process. In order to reduce the charge accumulated in the pattern, the high-conductivity liquid valve is opened to supply the high-conductivity liquid from the high-conductivity liquid nozzle to the back side of the substrate opposite to the surface where the pattern is not formed.

10. The substrate processing apparatus according to claim 9, further comprising: The facing member has a substrate facing surface facing the entire surface of the substrate held by the substrate holding unit, and is arranged at a close position where the substrate facing surface is close to the surface of the substrate.

11. The substrate processing apparatus according to claim 9 or 10, wherein: The substrate holding unit includes conductive pins formed of a conductive material, and the conductive pins are holding pins that contact and support the peripheral edge of the substrate.

12. The substrate processing apparatus according to claim 9 or 10, further comprising: a second low-conductive liquid supply unit configured to supply the low-conductive liquid to the back surface of the substrate held by the substrate holding unit, The control device also performs the following process: while performing the low-conductivity liquid supply process, in order to remove static electricity from the substrate, the low-conductivity liquid or the high-conductivity liquid is supplied to the back side of the substrate using the second low-conductivity liquid supply unit or the high-conductivity liquid nozzle.

13. The substrate processing apparatus according to claim 9 or 10, wherein: The control device does not supply liquid to the surface of the substrate while performing the highly conductive liquid supplying step.

14. The substrate processing apparatus according to claim 9 or 10, further comprising: a second high-conductive liquid supply unit for supplying the high-conductive liquid to the surface of the substrate held by the substrate holding unit, The control device further executes the following process: a second high-conductivity liquid supply process, after the low-conductivity liquid supply process and before the chemical liquid supply process, in order to remove static electricity from the substrate, using the second high-conductivity liquid supply unit to supply the high-conductivity liquid to the surface of the substrate.

15. The substrate processing apparatus according to claim 9 or 10, wherein: The low-conductivity liquid includes deionized water.

16. The substrate processing apparatus according to claim 9 or 10, wherein: The highly conductive liquid includes a liquid containing ions.

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