Substrate processing method

Abstract

To provide a substrate processing method capable of reducing the possibility that a substrate is contaminated by an organic substance.SOLUTION: A substrate processing method includes a holding step, a removing step, a removal rinsing step, and a hydrophobizing step. In the holding step, a substrate having a first main surface and a second main surface is held. In the removing step, the substrate is rotated and a hydrofluoric acid-containing liquid that contains hydrofluoric acid is supplied to the second major surface of the substrate. In the removal rinsing step, the substrate is rotated and the rinse liquid is supplied to the second major surface of the substrate after the removing step. In the hydrophobizing step, the substrate is rotated and the hydrophobizing liquid is supplied to the first major surface of the substrate after the removal rinsing step.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a substrate processing method. [Background technology]

[0002] Single-wafer substrate processing apparatuses for processing substrates have been disclosed in the past (for example, Patent Document 1). In Patent Document 1, the substrate processing apparatus hydrophobizes the surface of the substrate with a hydrophobizing liquid, then washes away the hydrophobizing liquid on the substrate with a rinse liquid, and then dries the substrate. This prevents the pattern on the substrate from collapsing during drying. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-27088 Summary of the Invention [Problem to be solved by the invention]

[0004] When a hydrophobizing liquid is supplied to the surface of a substrate, some of the hydrophobizing liquid flows around the edge of the substrate and acts on the peripheral edge of the back surface of the substrate. As a result, the peripheral edge of the back surface of the substrate is also hydrophobized. Hydrophobization is achieved by replacing substituents on the surface of the substrate with hydrophobic groups (organic substances). In other words, organic substances are present on the peripheral edge of the back surface of a processed substrate. Since the peripheral edge of the back surface of a processed substrate comes into contact with the hand of a transfer robot, there is a risk that the organic substances on the peripheral edge of the back surface will adhere to the hand. In other words, there is a risk of contaminating the hand. Furthermore, if a contaminated hand picks up another substrate, there is a risk of contaminating the other substrate.

[0005] Therefore, an object of the present disclosure is to provide a substrate processing method that can reduce the possibility of the substrate being contaminated by organic matter. [Means for solving the problem]

[0006] A first aspect is a substrate processing method, comprising: a holding step of holding a substrate having a first main surface and a second main surface; a removal step of rotating the substrate and supplying a hydrofluoric acid-containing liquid containing hydrofluoric acid to the second main surface of the substrate; a removal / rinse step of rotating the substrate after the removal step and supplying a rinse liquid to the second main surface of the substrate; and a hydrophobization step of rotating the substrate after the removal / rinse step and supplying a hydrophobization liquid to the first main surface of the substrate.

[0007] A second aspect is a substrate processing method according to the first aspect, further comprising: a chemical step performed before the removal step, in which the substrate is rotated and a chemical solution is supplied to the first main surface of the substrate to form an oxide on the first main surface of the substrate; and a chemical rinse step performed between the chemical step and the removal step, in which the substrate is rotated and a rinse solution is supplied to the first main surface of the substrate, wherein in the removal step, the oxide formed in the chemical step when the chemical solution flows around from the edge of the substrate to the second main surface and acts on the second main surface is removed by the hydrofluoric acid-containing liquid.

[0008] A third aspect is a substrate processing method according to the second aspect, wherein in the chemical process, the chemical is supplied to the first main surface of the substrate while rotating the substrate so that a liquid film of the chemical covers the entire first main surface of the substrate, which has hydrophobic properties.

[0009] A fourth aspect is a substrate processing method according to any one of the first to third aspects, wherein in the removing step, the hydrofluoric acid-containing liquid is supplied to the second main surface of the substrate while rotating the substrate, and the hydrofluoric acid-containing liquid is allowed to flow from the end surface of the substrate to the peripheral portion of the first main surface.

[0010] A fifth aspect is a substrate processing method according to any one of the first to fourth aspects, wherein in the removal step, a rinse liquid is supplied to the first main surface of the substrate in parallel with the supply of the hydrofluoric acid-containing liquid to the second main surface of the substrate.

[0011] A sixth aspect is a substrate processing method comprising: a holding step of holding a substrate having a first main surface and a second main surface; a removal step of rotating the substrate and supplying a removal liquid to the second main surface of the substrate to remove oxides; a removal / rinsing step of rotating the substrate after the removal step and supplying a rinse liquid to the second main surface of the substrate; and a hydrophobization step of rotating the substrate after the removal / rinsing step and supplying a hydrophobization liquid to the first main surface of the substrate. [Effects of the Invention]

[0012] According to the first and sixth aspects, since a hydrofluoric acid-containing liquid is supplied to the second main surface in the removing step, it is possible to remove most of the substituents on the second main surface of the substrate. Therefore, even if the hydrophobizing liquid flows around to the second main surface from the edge of the substrate in the hydrophobizing step, the second main surface is hardly hydrophobized. In other words, it is possible to reduce the possibility that the substituents on the substrate are replaced by hydrophobic groups (organic substances) in the molecules of the hydrophobizing liquid. In other words, it is possible to reduce the possibility that hydrophobic groups (organic substances) will adhere to the second main surface of the substrate.

[0013] According to the second aspect, the oxide film required for hydrophobization can be formed on the first main surface of the substrate in the chemical process, which allows the first main surface of the substrate to be appropriately hydrophobized in the hydrophobization process.

[0014] According to the third aspect, in the chemical process, the chemical is supplied so as to cover the entire first main surface, thereby reducing particle adhesion to the first main surface of the substrate. Furthermore, in order for the chemical to cover the entire hydrophobic first main surface, the flow rate of the chemical is increased, which makes it easier for the chemical to wrap around the edge of the substrate. Therefore, the chemical also acts on the edge of the substrate and the peripheral portion of the second main surface, forming oxides. However, in the removal process following the chemical process, most of the oxide on the second main surface can be removed. Therefore, even if the hydrophobizing liquid wraps around the edge of the substrate in the hydrophobizing process, the possibility of the second main surface being hydrophobized can be reduced.

[0015] According to the fourth aspect, it is possible to remove almost all oxides from the edge surface of the substrate. Therefore, it is possible to reduce the possibility that the edge surface of the substrate will be hydrophobized in the hydrophobic treatment step. In other words, it is possible to reduce the possibility that organic matter will adhere to the edge surface of the substrate.

[0016] According to the fifth aspect, it is possible to reduce the possibility of particles adhering to the first main surface of the substrate. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a plan view schematically showing an example of the configuration of a substrate processing apparatus. [Figure 2] FIG. 2 is a block diagram schematically illustrating an example of the internal configuration of a control unit. [Figure 3] FIG. 2 is a diagram schematically illustrating an example of the configuration of a processing unit according to the first embodiment. [Figure 4] 10 is a flowchart illustrating an example of an operation of a processing unit. [Figure 5] 10A to 10C are diagrams each showing an example of a processing unit in each step; [Figure 6] 10A to 10C are diagrams each showing an example of a processing unit in each step; [Figure 7] 10A to 10C are diagrams each showing an example of a processing unit in each step; [Figure 8] 10A to 10C are diagrams each showing an example of a processing unit in each step; [Figure 9] FIG. 10 is a diagram schematically illustrating an example of the configuration of a processing unit according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, the embodiments will be described in detail with reference to the drawings. In the drawings, the dimensions and numbers of parts are exaggerated or simplified as necessary for ease of understanding. Parts having similar configurations and functions are denoted by the same reference numerals, and duplicate explanations will be omitted below.

[0019] In the following description, the same components are denoted by the same reference numerals, and their names and functions are also the same. Therefore, detailed descriptions of them may be omitted to avoid duplication.

[0020] Furthermore, in the following description, even if ordinal numbers such as "first" or "second" are used, these terms are used for convenience to facilitate understanding of the contents of the embodiments, and are not limited to the order that may result from these ordinal numbers.

[0021] When expressions indicating relative or absolute positional relationships (e.g., "in one direction," "along one direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.) are used, unless otherwise specified, the expressions not only strictly represent the positional relationship but also represent a state in which there is a relative displacement in terms of angle or distance within a range in which tolerance or equivalent functionality is obtained. When expressions indicating an equal state (e.g., "identical," "equal," "homogeneous," etc.) are used, the expressions not only represent a state in which there is strict quantitative equality but also represent a state in which there is a difference in which tolerance or equivalent functionality is obtained, unless otherwise specified. When expressions indicating a shape (e.g., "rectangular shape" or "cylindrical shape," etc.) are used, the expressions not only represent a geometrically strict shape but also represent a shape with, for example, irregularities or chamfers within a range in which equivalent effects are obtained. When the expressions "comprise," "include," "have," "includes," "includes," or "have" are used to describe one component, the expressions are not exclusive expressions that exclude the presence of other components. When the phrase "at least one of A, B, and C" is used, the phrase includes A only, B only, C only, any two of A, B, and C, and all of A, B, and C.

[0022] First Embodiment <Overall configuration of substrate processing equipment> 1 is a plan view schematically showing an example of the configuration of a substrate processing apparatus 100. The substrate processing apparatus 100 is a single-wafer processing apparatus that processes substrates W one by one.

[0023] The substrate W may be, for example, a semiconductor wafer, a liquid crystal display substrate, an organic electroluminescence (EL) substrate, an FPD (Flat Panel Display) substrate, an optical display substrate, a magnetic disk substrate, an optical disk substrate, a magneto-optical disk substrate, a photomask substrate, or a solar cell substrate. The substrate W has a thin, flat plate shape. Hereinafter, both main surfaces of the substrate W will be referred to as the first main surface Wa and the second main surface Wb, respectively. The second main surface Wb is the surface opposite to the first main surface Wa. Hereinafter, the substrate W will be considered to be a semiconductor wafer. The substrate W may be, for example, a silicon semiconductor. The substrate W has, for example, a disk shape. The diameter of the substrate W is, for example, about 300 mm, and the thickness of the substrate W is, for example, not less than about 0.5 mm and not more than about 3 mm. A pattern is formed on the first main surface Wa of the substrate W. The pattern here includes, for example, a semiconductor pattern.

[0024] 1, the substrate processing apparatus 100 includes an indexer block 110, a processing block 120, and a control unit 90. The processing block 120 is a section that mainly processes substrates W, and the indexer block 110 is a section that mainly transports substrates W between the outside of the substrate processing apparatus 100 and the processing block 120.

[0025] The indexer block 110 includes a load port 111 and a first transport part 112. A substrate container (hereinafter referred to as a carrier) C that has been carried in from outside is placed on the load port 111. The carrier C accommodates a plurality of substrates W, for example, arranged at intervals in the vertical direction. In the example of FIG. 1, a plurality of load ports 111 are arranged.

[0026] The first transport unit 112 is a transport robot and can remove an unprocessed substrate W from a carrier C placed on each load port 111. The first transport unit 112 may also be called an indexer robot. The first transport unit 112 transports the unprocessed substrate W removed from the carrier C to the processing block 120. The processing block 120 can process the unprocessed substrate W. The first transport unit 112 can also receive a processed substrate W from the processing block 120 and transport the processed substrate W to a carrier C in the load port 111.

[0027] In the example of FIG. 1, the processing block 120 includes a plurality of processing units 1 and a second transport part 122. The second transport part 122 is a transport robot and can transport substrates W between the first transport part 112 and the plurality of processing units 1. In the example of FIG. 1, the processing block 120 also includes a mounting part 123. The mounting part 123 is, for example, a shelf on which a plurality of substrates W can be placed in a vertically aligned state. The first transport part 112 mounts an unprocessed substrate W on the mounting part 123. The second transport part 122 removes the unprocessed substrate W from the mounting part 123 and transports the substrate W to the processing unit 1. The processing unit 1 processes the substrate W. The configuration of the processing unit 1 will be described later. The second transport part 122 removes the processed substrate W from the processing unit 1 and transports the substrate W to the mounting part 123. The first transport part 112 takes out the substrate W from the platform 123 and transports the substrate W to the carrier C of the load port 111 .

[0028] 1, a plurality of (for example, four) processing units 1 are arranged to surround the second transport section 122 in a plan view. This second transport section 122 may also be called a center robot. At each position in a plan view, a plurality of processing units 1 may be stacked vertically. In other words, a plurality of (four in the figure) towers TW each made up of a plurality of processing units 1 stacked vertically may be arranged to surround the second transport section 122.

[0029] The control unit 90 comprehensively controls the substrate processing apparatus 100. Specifically, the control unit 90 controls the first transport unit 112, the second transport unit 122, and the processing unit 1. FIG. 2 is a block diagram schematically illustrating an example of the internal configuration of the control unit 90. The control unit 90 is an electronic circuit and includes, for example, a data processing unit 91 and a storage unit 92. In the specific example of FIG. 2, the data processing unit 91 and the storage unit 92 are connected to each other via a bus 93. The data processing unit 91 may be an arithmetic processing device such as a central processing unit (CPU). The storage unit 92 may include a non-transitory storage unit (e.g., a read-only memory (ROM)) 921 and a temporary storage unit (e.g., a random access memory (RAM)) 922. The non-transitory storage unit 921 may store, for example, a program that defines the processing to be performed by the control unit 90. The data processing unit 91 executes this program, allowing the control unit 90 to perform the processing defined in the program. Of course, some or all of the processing performed by the control unit 90 may be performed by hardware such as a dedicated logic circuit.

[0030] <Processing unit overview> Fig. 3 is a diagram schematically illustrating an example of the configuration of a processing unit 1 according to the first embodiment. Note that all processing units 1 in the substrate processing apparatus 100 do not necessarily have the configuration illustrated in Fig. 3. It is sufficient that at least one processing unit 1 in the substrate processing apparatus 100 has the configuration illustrated in Fig. 3.

[0031] The processing unit 1 includes a substrate holder 2 and a discharge unit 3 .

[0032] In the example of Figure 3, the processing unit 1 also includes a chamber 10. The chamber 10 has a box-like shape, and its internal space corresponds to a processing space in which a substrate W is processed. The chamber 10 is provided with an openable / closable loading / unloading port (not shown). The second transport part 122 loads an unprocessed substrate W into the chamber 10 through the loading / unloading port, and loads a processed substrate W out of the chamber 10 through the loading / unloading port.

[0033] The substrate holder 2 is provided in the chamber 10 and holds the substrate W in a horizontal position while rotating the substrate W around a rotation axis Q1. The horizontal position here means that the thickness direction of the substrate W is aligned with the vertical direction. The rotation axis Q1 is an axis that passes through the center of the substrate W and is aligned with the vertical direction. Such a substrate holder 2 may also be called a spin chuck.

[0034] In this example, the first main surface Wa of the substrate W on which the pattern is formed faces vertically upward. That is, in the example of Fig. 3, the first main surface Wa of the substrate W held by the substrate holder 2 corresponds to the upper surface, and the second main surface Wb of the substrate W corresponds to the lower surface.

[0035] In the example of FIG. 3, the substrate holding unit 2 includes a spin base 21, chuck pins 22, and a rotation drive unit 23. The spin base 21 has a plate-like shape (e.g., a disk shape) and is disposed with its thickness direction aligned vertically. A plurality of chuck pins 22 are provided on the upper surface of the spin base 21. The plurality of chuck pins 22 are disposed at equal intervals along the circumferential direction about the rotation axis Q1. The plurality of chuck pins 22 are disposed so as to be displaceable between a holding position and a release position, which will be described below. The holding position is a position where the chuck pins 22 abut against the periphery of the substrate W. The plurality of chuck pins 22 hold the substrate W by stopping at their respective holding positions. FIG. 3 shows the chuck pins 22 stopped at the holding position. The release position is a position where each chuck pin 22 is separated from the substrate W. The plurality of chuck pins 22 stop at their respective release positions, thereby releasing the substrate W from the holding of the substrate W by the plurality of chuck pins 22. The substrate holder 2 also includes a pin drive unit (not shown) that displaces the chuck pins 22. The pin drive unit includes a drive source such as a motor and an air cylinder, and is controlled by the control unit 90.

[0036] The rotation drive unit 23 includes a shaft 231 and a motor 232. The upper end of the shaft 231 is connected to the lower surface of the spin base 21, and the shaft 231 extends from the lower surface of the spin base 21 along a rotation axis Q1. The motor 232 is controlled by the control unit 90 to rotate the shaft 231 about the rotation axis Q1. This causes the spin base 21, chuck pins 22, and substrate W to rotate integrally about the rotation axis Q1.

[0037] It should be noted that the substrate holder 2 does not necessarily have to have the chuck pins 22. For example, the substrate holder 2 may hold the substrate W by a chuck method such as a vacuum chuck, an electrostatic chuck, or a Bernoulli chuck.

[0038] The discharger 3 discharges a processing liquid toward each of the first main surface Wa and the second main surface Wb of the substrate W held by the substrate holder 2. The discharger 3 can discharge a hydrophobizing liquid, which is an example of a processing liquid, onto the first main surface Wa of the substrate W. The discharger 3 can also discharge a hydrofluoric acid-containing liquid, which is an example of a processing liquid, onto the second main surface Wb of the substrate W.

[0039] 3, the discharge unit 3 includes at least one upper surface nozzle 4 and at least one lower surface nozzle 5. Each of the upper surface nozzle 4 and the lower surface nozzle 5 is, for example, a straight nozzle that discharges the processing liquid in the form of a liquid column.

[0040] In the example of FIG. 3, the discharge unit 3 includes a hydrophobic nozzle 4a as an example of the upper surface nozzle 4. The hydrophobic nozzle 4a is provided in the chamber 10 above the substrate W held by the substrate holder 2. The hydrophobic nozzle 4a discharges a hydrophobic liquid toward the first main surface Wa of the substrate W. The hydrophobic liquid is a liquid that hydrophobizes the surface of the substrate W. The hydrophobic liquid is, for example, a silylation liquid containing a liquid silylating agent (also called a silane coupling agent). The silylation agent contains, for example, HMDS (hexamethyldisilazane). The hydrophobic liquid is, for example, a liquid that replaces substituents present on the first main surface Wa of the substrate W with hydrophobic groups. The substituents are, for example, hydroxyl groups (OH groups). The hydroxyl groups are hydrophilic groups. The hydrophobic groups are organic hydrophobic groups contained in the molecules of the hydrophobic liquid, for example, trimethylsilyl groups. In this case, the hydrogen molecules of the hydroxy groups present on the surface of the substrate W are substituted with trimethylsilyl groups, thereby making the surface of the substrate W hydrophobic.

[0041] In the example of FIG. 3, the discharge unit 3 includes a supply pipe 41a, a supply valve 42a, and a flow rate adjustment valve 43a. The downstream end of the supply pipe 41a is connected to the hydrophobization nozzle 4a, and the upstream end of the supply pipe 41a is connected to a hydrophobization liquid supply source. The hydrophobization liquid supply source includes, for example, a tank that stores the hydrophobization liquid. The supply valve 42a and the flow rate adjustment valve 43a are inserted in the supply pipe 41a. The supply valve 42a switches the opening and closing of the supply pipe 41a, and the flow rate adjustment valve 43a adjusts the flow rate of the hydrophobization liquid flowing through the supply pipe 41a. The supply valve 42a and the flow rate adjustment valve 43a are controlled by the control unit 90.

[0042] In the example of Figure 3, the hydrophobic nozzle 4a is provided so as to be movable by a movement drive unit 45a. The movement drive unit 45a moves the hydrophobic nozzle 4a between a processing position and a standby position, which will be described below. The processing position is a position where the hydrophobic nozzle 4a ejects the hydrophobic liquid, and is, for example, a position vertically opposite the center of the substrate W. In the example of Figure 3, the hydrophobic nozzle 4a is shown stopped at the processing position. The standby position is a position where the hydrophobic nozzle 4a does not eject the hydrophobic liquid, and is, for example, a position radially outward from the substrate W.

[0043] FIG. 3 shows an example of the specific configuration of the movement drive unit 45a. In the example shown in FIG. 3, the movement drive unit 45a includes an arm 451, a support column 452, and a drive source 453. The support column 452 is disposed radially outward of the guard 7 (described later) and extends vertically. The arm 451 extends horizontally, with its tip connected to the hydrophobic nozzle 4a and its base connected to the support column 452. The drive source 453 is controlled by the control unit 90 to rotate the support column 452 in forward and reverse directions within a predetermined angular range around its central axis Q2. The drive source 453 includes, for example, a motor. When the support column 452 rotates in forward and reverse directions within a predetermined angular range around the central axis Q2, the hydrophobic nozzle 4a reciprocates in the circumferential direction about the central axis Q2. The support column 452 is installed so that a processing position and a standby position are located on the movement trajectory of the hydrophobic nozzle 4a. The movement drive unit 45a is not necessarily limited to the embodiment shown in FIG. 3, and may include a direct-acting mechanism such as a linear motor.

[0044] When the hydrophobizing nozzle 4a discharges the hydrophobizing liquid onto the first main surface Wa of the substrate W while the substrate W is rotating, the hydrophobizing liquid lands in the center of the first main surface Wa of the substrate W, flows radially outward as the substrate W rotates, and splashes outward from the periphery of the substrate W. The hydrophobizing liquid acts on the first main surface Wa of the substrate W, thereby hydrophobizing the first main surface Wa of the substrate W.

[0045] The lower surface nozzle 5 is provided in the chamber 10 below the substrate W held by the substrate holding unit 2. The lower surface nozzle 5 discharges a hydrofluoric acid-containing liquid toward the second main surface Wb of the substrate W. The hydrofluoric acid-containing liquid is a liquid containing hydrofluoric acid, such as dilute hydrofluoric acid. In the example of FIG. 3, the lower surface nozzle 5 is provided at a position vertically opposite the center of the substrate W. As shown in FIG. 3, the lower surface nozzle 5 may protrude from the center of the spin base 21 of the substrate holding unit 2 toward the second main surface Wb of the substrate W.

[0046] In the example of FIG. 3, the discharge unit 3 includes a supply pipe 51a, a supply valve 52a, and a flow rate control valve 53a. The downstream end of the supply pipe 51a is connected to the lower surface nozzle 5, and the upstream end of the supply pipe 51a is connected to a hydrofluoric acid-containing liquid supply source. In the example of FIG. 3, a through-hole is formed in the center of the spin base 21 of the substrate holder 2, and the shaft 231 is a hollow shaft. A portion of the supply pipe 51a extends vertically through the through-hole of the spin base 21 and the hollow portion of the shaft 231. The hydrofluoric acid-containing liquid supply source includes, for example, a tank that stores the hydrofluoric acid-containing liquid. The supply valve 52a and the flow rate control valve 53a are inserted in the supply pipe 51a. The supply valve 52a switches the opening and closing of the supply pipe 51a, and the flow rate control valve 53a adjusts the flow rate of the hydrofluoric acid-containing liquid flowing through the supply pipe 51a. The supply valve 52a and the flow rate control valve 53a are controlled by the control unit 90.

[0047] 3, the discharge unit 3 is capable of discharging a processing liquid other than the hydrophobizing liquid and the hydrofluoric acid-containing liquid toward the substrate W. Specifically, the discharge unit 3 includes, as examples of the upper surface nozzles 4, a first rinse nozzle 4b, a second rinse nozzle 4c, a first chemical liquid nozzle 4d, and a second chemical liquid nozzle 4e.

[0048] First chemical liquid nozzle 4d is provided in chamber 10 above substrate W held by substrate holding unit 2. In the example of FIG. 3, first chemical liquid nozzle 4d is provided so as to be movable by movement drive unit 45d. Movement drive unit 45d moves first chemical liquid nozzle 4d between a processing position and a standby position. The processing position is a position where first chemical liquid nozzle 4d discharges the first chemical liquid, for example, a position vertically facing the center of substrate W. The processing positions for the other top surface nozzles 4 are similar. The standby position is a position where first chemical liquid nozzle 4d does not discharge the first chemical liquid, for example, a position radially outward from substrate holding unit 2. The standby positions for the other top surface nozzles 4 are similar. Movement drive unit 45d has, for example, a configuration similar to that of movement drive unit 45a.

[0049] When the first chemical liquid nozzle 4d is positioned at the processing position, it discharges a first chemical liquid toward the first main surface Wa of the substrate W. The first chemical liquid is, for example, a liquid for cleaning the substrate W, and a specific example is a liquid for removing a native oxide film. More specifically, the first chemical liquid contains hydrofluoric acid. The first chemical liquid may be dilute hydrofluoric acid. The first chemical liquid can remove a native oxide film on the first main surface Wa of the substrate W.

[0050] Second chemical liquid nozzle 4e is provided in chamber 10 above substrate W held by substrate holder 2. In the example of Fig. 3, second chemical liquid nozzle 4e is provided so as to be movable by movement driver 45e. Movement driver 45e moves second chemical liquid nozzle 4e between a processing position and a standby position. Movement driver 45e has a configuration similar to that of movement driver 45a, for example.

[0051] When the second chemical liquid nozzle 4e is positioned at the processing position, it discharges a second chemical liquid toward the first main surface Wa of the substrate W. The second chemical liquid is, for example, a liquid that forms an oxide on the substrate W. The second chemical liquid is, for example, a mixed liquid of ammonium hydroxide, hydrogen peroxide, and water (i.e., SC1). When the second chemical liquid is SC1, it can remove impurities such as particles from the first main surface Wa of the substrate W.

[0052] The first rinse nozzle 4b is provided in the chamber 10 above the substrate W held by the substrate holder 2. In the example of Fig. 3, the first rinse nozzle 4b is provided so as to be movable by a movement driver 45b. The movement driver 45b moves the first rinse nozzle 4b between a processing position and a standby position. The movement driver 45b has, for example, the same configuration as the movement driver 45a.

[0053] When positioned at the processing position, the first rinse nozzle 4b discharges a first rinse liquid toward the first main surface Wa of the substrate W. The first rinse liquid is, for example, pure water (i.e., deionized water). For example, after the discharge unit 3 discharges the first chemical liquid from the first chemical liquid nozzle 4d toward the substrate W, the first rinse liquid is discharged toward the substrate W from the first rinse nozzle 4b. This allows the first chemical liquid on the first main surface Wa of the substrate W to be washed away by the first rinse liquid. In other words, the processing liquid on the first main surface Wa of the substrate W can be replaced from the first chemical liquid to the first rinse liquid. After the second chemical liquid is supplied to the substrate W, the first rinse nozzle 4b also discharges the first rinse liquid toward the first main surface Wa of the substrate W. This allows the processing liquid on the first main surface Wa of the substrate W to be replaced from the second chemical liquid to the first rinse liquid.

[0054] The second rinse nozzle 4c is provided in the chamber 10 above the substrate W held by the substrate holder 2. In the example of Fig. 3, the second rinse nozzle 4c is provided so as to be movable by a movement driver 45c. The movement driver 45c moves the second rinse nozzle 4c between a processing position and a standby position. The movement driver 45c has, for example, a configuration similar to that of the movement driver 45a.

[0055] When the second rinse nozzle 4c is positioned at the processing position, it ejects a second rinse liquid toward the first main surface Wa of the substrate W. The second rinse liquid is, for example, an organic solvent. The volatility of the second rinse liquid may be higher than that of the first rinse liquid. The surface tension of the second rinse liquid may be lower than that of the first rinse liquid. The organic solvent is, for example, isopropyl alcohol. For example, after the ejection unit 3 ejects the first rinse liquid from the first rinse nozzle 4b toward the substrate W, it ejects the second rinse liquid from the second rinse nozzle 4c toward the substrate W. This allows the processing liquid on the first main surface Wa of the substrate W to be replaced from the first rinse liquid with the second rinse liquid.

[0056] 3, discharge unit 3 includes supply pipe 41b, supply valve 42b, and flow rate adjustment valve 43b for first rinse nozzle 4b, supply pipe 41c, supply valve 42c, and flow rate adjustment valve 43c for second rinse nozzle 4c, supply pipe 41d, supply valve 42d, and flow rate adjustment valve 43d for first chemical liquid nozzle 4d, and supply pipe 41e, supply valve 42e, and flow rate adjustment valve 43e for second chemical liquid nozzle 4e. The positional relationship between these is similar to the positional relationship between hydrophobic nozzle 4a, supply pipe 41a, supply valve 42a, and flow rate adjustment valve 43a.

[0057] In the above example, a movement drive unit is provided for each upper surface nozzle 4, but it is also possible to provide a movement drive unit that moves multiple upper surface nozzles 4. Furthermore, in the above example, an individual upper surface nozzle 4 is provided for each processing liquid, but it is also possible to provide an upper surface nozzle 4 that is shared by multiple processing liquids.

[0058] In the example of FIG. 3, the lower nozzle 5 of the discharge unit 3 is capable of discharging a first rinse liquid. In the example of FIG. 3, the supply pipe 51a includes a common pipe 50, a first branch pipe 50a, and a second branch pipe 50b. A portion of the common pipe 50 extends vertically through the through-hole of the spin base 21 and the hollow portion of the shaft 231. The downstream end of the common pipe 50 is connected to the lower nozzle 5. The downstream ends of the first branch pipe 50a and the second branch pipe 50b are connected to the upstream end of the common pipe 50. The upstream end of the first branch pipe 50a is connected to a hydrofluoric acid-containing liquid supply source, and the upstream end of the second branch pipe 50b is connected to a first rinse liquid supply source. The common pipe 50 and the first branch pipe 50a form a supply pipe 51a, and the common pipe 50 and the second branch pipe 50b form a supply pipe 51b. The supply pipe 51b connects the lower nozzle 5 to the first rinse liquid supply source.

[0059] Supply valve 52a and flow rate adjustment valve 53a are inserted in first branch pipe 50a. Supply valve 52b and flow rate adjustment valve 53b are inserted in second branch pipe 50b. Supply valve 52b switches between opening and closing of supply pipe 51b, and flow rate adjustment valve 53b adjusts the flow rate of the second rinse liquid flowing through supply pipe 51b. Supply valve 52b and flow rate adjustment valve 53b are controlled by control unit 90.

[0060] In the example of FIG. 3, the processing unit 1 is provided with a guard 7. The guard 7 has a cylindrical shape with the rotation axis Q1 as its central axis, and surrounds the substrate holder 2. The guard 7 can catch various processing liquids that splash from the periphery of the substrate W. The processing liquids flow down along the inner peripheral surface of the guard 7. The processing liquids are discharged to the outside of the chamber 10 through a discharge pipe (not shown) provided at the bottom of the guard 7.

[0061] <Operation example of substrate processing apparatus> Next, an example of the operation of the processing unit 1 (i.e., a substrate processing method) will be described. Fig. 4 is a flowchart showing an example of the operation of the processing unit 1. The control unit 90 causes the processing unit 1 to perform the processes from step S1 to step S13 in accordance with a preset processing procedure (recipe). Figs. 5 to 8 are diagrams schematically showing an example of the state of the processing unit 1 at each step.

[0062] First, the second transport unit 122 transports the substrate W to the processing unit 1. Then, the substrate holding unit 2 holds the substrate W received from the second transport unit 122 (step S1: holding step). As a specific example, the substrate holding unit 2 displaces the plurality of chuck pins 22 from their respective release positions to their holding positions. As a result, the plurality of chuck pins 22 hold the substrate W. The substrate holding unit 2 continues to hold the substrate W until the processing on the substrate W is completed.

[0063] Next, the substrate holder 2 starts rotating the substrate W (step S2: rotation start step). The substrate holder 2 may continue rotating the substrate W until the processing of the substrate W is completed.

[0064] Next, the processing unit 1 rotates the substrate W and supplies the first chemical liquid to the first main surface Wa of the substrate W (Step S3: First Chemical Liquid Step: First Chemical Liquid Supply). Specifically, first, the movement drive unit 45d moves the first chemical liquid nozzle 4d to the processing position. Then, the control unit 90 opens the supply valve 42d. As a result, as shown in FIG. 5(a), the first chemical liquid is discharged from the first chemical liquid nozzle 4d toward the first main surface Wa of the rotating substrate W. The first chemical liquid lands on, for example, the center of the first main surface Wa of the substrate W. The first chemical liquid that has landed on the first main surface Wa of the substrate W flows radially outward due to centrifugal force caused by the rotation of the substrate W and is scattered from the periphery of the substrate W.

[0065] The control unit 90 controls the flow rate adjustment valve 43d and the substrate holding unit 2 to a flow rate (target value) and a rotation speed (target value) such that the entire first main surface Wa of the substrate W is covered with a liquid film of the processing liquid (here, the first chemical liquid). In other words, the flow rate (target value) of the first chemical liquid and the rotation speed (target value) of the substrate W are set so that the entire first main surface Wa is covered with a liquid film of the first chemical liquid. This reduces the possibility of particles adhering to the first main surface Wa of the substrate W. This also applies to the steps described below in which other processing liquids are discharged.

[0066] The first chemical liquid acts on the first main surface Wa of the substrate W, thereby performing a process on the first main surface Wa of the substrate W according to the type of the first chemical liquid. When the first chemical liquid contains hydrofluoric acid, for example, a native oxide film on the first main surface Wa of the substrate W is removed. The native oxide film is, for example, a silicon oxide film. When the native oxide film on the first main surface Wa of the substrate W is removed, the underlying layer on the first main surface Wa of the substrate W is exposed. The underlying layer is, for example, silicon. After the first chemical liquid treatment, the first main surface Wa of the substrate W is hydrophobic, for example. In other words, the contact angle of the first main surface Wa of the substrate W from which the native oxide film has been removed is larger than the contact angle of the first main surface Wa of the substrate W from which the native oxide film has been formed. The contact angle when water is dropped on the first main surface Wa of the substrate W from which the native oxide film has been removed may be, for example, 90 degrees or more.

[0067] As shown in FIG. 5(a), the processing unit 1 may supply a first rinse liquid to the second main surface Wb of the substrate W in parallel with the supply of the first chemical liquid. Specifically, the control unit 90 opens the supply valve 52b. This causes the first rinse liquid to be ejected from the lower surface nozzle 5 toward the second main surface Wb of the rotating substrate W. The first rinse liquid lands on, for example, the center of the second main surface Wb of the substrate W. The first rinse liquid that has landed on the second main surface Wb of the substrate W is subjected to centrifugal force accompanying the rotation of the substrate W, flows radially outward, and is scattered from the periphery of the substrate W. This reduces the possibility of particles adhering to the second main surface Wb of the substrate W.

[0068] When the substrate W has been sufficiently processed with the first chemical liquid, the control unit 90 closes the supply valve 42d. As a specific example, the control unit 90 determines whether the elapsed time from the start of the discharge of the first chemical liquid is equal to or longer than a predetermined first chemical liquid time. The first chemical liquid time is set in advance to a time sufficient for the processing with the first chemical liquid to be performed. The elapsed time is measured, for example, by a timer circuit (not shown) belonging to the control unit 90. When the elapsed time is equal to or longer than the first chemical liquid time, the control unit 90 closes the supply valve 42d. In addition, the movement drive unit 45d moves the first chemical liquid nozzle 4d to the standby position.

[0069] Next, the processing unit 1 rotates the substrate W and supplies a first rinse liquid to the first main surface Wa of the substrate W (Step S4: First Chemical Liquid Rinse Step: Supply of First Rinse Liquid). Specifically, first, the movement driver 45b moves the first rinse nozzle 4b to the processing position. Then, the control unit 90 opens the supply valve 42b. As a result, as shown in FIG. 5B, the first rinse liquid is discharged from the first rinse nozzle 4b toward the first main surface Wa of the rotating substrate W. The first rinse liquid lands on, for example, the center of the first main surface Wa of the substrate W. The first rinse liquid that has landed on the first main surface Wa of the substrate W flows radially outward due to centrifugal force caused by the rotation of the substrate W and is scattered from the periphery of the substrate W. At this time, the first rinse liquid pushes the processing liquid (here, the first chemical liquid) on the first main surface Wa of the substrate W outward in the radial direction. As a result, the processing liquid on the first main surface Wa of the substrate W is replaced from the first chemical liquid to the first rinse liquid.

[0070] As shown in FIG. 5(b), the processing unit 1 may supply the first rinse liquid to the second main surface Wb of the substrate W in parallel with the supply of the first rinse liquid to the first main surface Wa of the substrate W.

[0071] When the first chemical liquid has been sufficiently replaced with the first rinse liquid, the control unit 90 closes the supply valve 42b. As a specific example, the control unit 90 measures the elapsed time from the start of the discharge of the first rinse liquid, and closes the supply valve 42b when the elapsed time is equal to or longer than a predetermined first chemical rinse time. The first chemical rinse time is set in advance to a time sufficient to replace the first chemical liquid with the first rinse liquid. After the supply valve 42b is closed, the movement driver 45b moves the first rinse nozzle 4b to the standby position.

[0072] Next, the processing unit 1 rotates the substrate W and supplies the second chemical liquid to the first main surface Wa of the substrate W (Step S5: Second Chemical Liquid Step: Supply of Second Chemical Liquid (Oxidizing Liquid)). Specifically, the movement driver 45e moves the second chemical liquid nozzle 4e to the processing position, and the control unit 90 opens the supply valve 42e. As a result, as shown in FIG. 6(a), the second chemical liquid is discharged from the second chemical liquid nozzle 4e toward the first main surface Wa of the rotating substrate W. The second chemical liquid lands on, for example, the center of the first main surface Wa of the substrate W. The second chemical liquid that has landed on the first main surface Wa of the substrate W flows radially outward due to centrifugal force caused by the rotation of the substrate W and is scattered from the periphery of the substrate W. At this time, the second chemical liquid acts on the first main surface Wa of the substrate W, thereby performing chemical processing on the first main surface Wa of the substrate W according to the type of the second chemical liquid. The second chemical liquid is a liquid that has the effect of oxidizing the surface of the substrate W. Therefore, the second chemical liquid can also be said to be an oxidizing liquid. When the second chemical liquid is SC1, the processing unit 1 can also remove impurities such as particles on the first main surface Wa of the substrate W.

[0073] The control unit 90 controls the flow rate adjustment valve 43e and the substrate holder 2 to a flow rate (target value) and a rotation speed (target value) such that the entire first main surface Wa of the substrate W is covered with a liquid film of the processing liquid (here, the second chemical liquid). In other words, the flow rate (target value) of the second chemical liquid and the rotation speed (target value) of the substrate W are set so that the entire first main surface Wa is covered with a liquid film of the second chemical liquid. This reduces the possibility of particles adhering to the first main surface Wa of the substrate W. If the first main surface Wa of the substrate W is hydrophobic, the flow rate of the second chemical liquid is set relatively large. Therefore, as shown in FIG. 6(b), the second chemical liquid is likely to flow around the edge surface We of the substrate W and may also act on the peripheral portions of the edge surface We and the second main surface Wb of the substrate W. This may result in oxidation of the edge surface We and the peripheral portions of the second main surface Wb of the substrate W.

[0074] As described above, by the treatment with the second chemical liquid, an oxide film is formed on the first main surface Wa of the substrate W, and may also be formed on the edge surface We and the peripheral portion of the second main surface Wb of the substrate W. The oxide film may be, for example, a silicon oxide film. OH groups are present on the surface of this oxide film as substituents used for hydrophobization, which will be described later.

[0075] As shown in FIG. 6(a), the processing unit 1 may supply a first rinse liquid to the second main surface Wb of the substrate W in parallel with the supply of the second chemical liquid. Specifically, the control unit 90 opens the supply valve 52b. This causes the first rinse liquid to be ejected from the lower surface nozzle 5 toward the second main surface Wb of the rotating substrate W. The first rinse liquid flows radially outward across the second main surface Wb of the substrate W and splashes outward from the periphery of the substrate W. This reduces the possibility of particles adhering to the second main surface Wb of the substrate W. Furthermore, the first rinse liquid pushes the second chemical liquid that has flowed around the edge Wc of the substrate W radially outward, thereby reducing the amount of the second chemical liquid that flows around.

[0076] When the substrate W has been sufficiently processed with the second chemical liquid, the control unit 90 closes the supply valve 42e. As a specific example, the control unit 90 closes the supply valve 42e when the elapsed time from the start of the discharge of the second chemical liquid is equal to or longer than a predetermined second chemical liquid time. The second chemical liquid time is set in advance to a time sufficient for the processing with the second chemical liquid to be sufficiently performed. In addition, the movement drive unit 45d moves the second chemical liquid nozzle 4e to the standby position.

[0077] Next, the processing unit 1 rotates the substrate W and supplies a first rinse liquid to the first main surface Wa of the substrate W (step S6: second chemical liquid rinsing step: supply of first rinse liquid). As a result, the processing liquid on the first main surface Wa of the substrate W is replaced from the second chemical liquid with the first rinse liquid. Note that the processing unit 1 may also supply the first rinse liquid to the second main surface Wb of the substrate W in parallel with supplying the first rinse liquid to the first main surface Wa of the substrate W.

[0078] When the second chemical liquid has been sufficiently replaced with the first rinsing liquid, the processing unit 1 supplies a hydrofluoric acid-containing liquid to the second main surface Wb of the substrate W (step S7: removal process: supply of removal liquid (hydrofluoric acid-containing liquid)). As a specific example, the control unit 90 closes the supply valve 52b and opens the supply valve 52a when the elapsed time from the start of the discharge of the first rinsing liquid reaches or exceeds a predetermined second chemical rinsing time. The second chemical rinsing time is preset to a time sufficient for the first rinsing liquid to be sufficiently replaced with the second chemical liquid. When the supply valve 52a opens, the hydrofluoric acid-containing liquid is discharged from the lower nozzle 5 toward the second main surface Wb of the substrate W, as shown in FIG. 7(a). The hydrofluoric acid-containing liquid lands on, for example, the center of the second main surface Wb of the substrate W. The hydrofluoric acid-containing liquid that has landed on the second main surface Wb of the substrate W flows radially outward due to the centrifugal force of the substrate W and splashes off from the periphery of the substrate W. The hydrofluoric acid-containing liquid acts on the second main surface Wb of the substrate W, thereby removing at least a portion of the oxides formed on the second main surface Wb of the substrate W. More specifically, the oxides on the second main surface Wb of the substrate W are almost completely removed. The hydrofluoric acid-containing liquid can also be considered a removal liquid that removes oxides. Although substituents used for hydrophobization are present on the surface of the oxides, the hydrofluoric acid-containing liquid removes most of the oxides, and therefore, it is possible to remove almost all of the substituents from the second main surface Wb of the substrate W.

[0079] 7(a), the processing unit 1 may supply a first rinse liquid to the first main surface Wa of the substrate W in parallel with supplying the hydrofluoric acid-containing liquid to the second main surface Wb of the substrate W. This reduces the possibility of particles adhering to the first main surface Wa of the substrate W.

[0080] As shown in FIG. 7(b), the processing unit 1 may control the flow rate control valve 43b, the flow rate control valve 53a, and the rotation driver 23 under processing conditions such that the hydrofluoric acid-containing liquid flows over the entire edge surface We of the substrate W. That is, the flow rate (target value) of the first rinse liquid, the flow rate (target value) of the hydrofluoric acid-containing liquid, and the rotation speed (target value) of the substrate W may be set so that the hydrofluoric acid-containing liquid flows over the entire edge surface We of the substrate W. The first main surface Wa of the substrate W has a device region Wa1 where devices are formed and a peripheral region where no devices are formed. The peripheral region is a region surrounding the device region Wa1 in a plan view. The width of the peripheral region is, for example, 0.5 mm or more and 5 mm or less. The processing unit 1 may control the flow rate control valve 43b, the flow rate control valve 53a, and the rotation driver 23 under processing conditions such that the hydrofluoric acid-containing liquid does not enter the device region Wa1 but flows over the peripheral region. As a result, most of the oxides on the edge Wc of the substrate W can be removed.

[0081] When the oxides on the peripheral portion of the second main surface Wb of the substrate W and on the entire edge surface We of the substrate W have been sufficiently removed, the control unit 90 closes the supply valve 52a. As a specific example, the control unit 90 closes the supply valve 52a when the elapsed time from the start of the discharge of the hydrofluoric acid-containing liquid reaches or exceeds a predetermined removal time. The removal time is set in advance to a time sufficient to sufficiently remove the oxides on the peripheral portion of the second main surface Wb and the edge surface We of the substrate W.

[0082] Next, the processing unit 1 supplies a first rinse liquid to the second main surface Wb of the substrate W (step S8: removal rinse process (first rinse process): supply first rinse liquid). Specifically, the control unit 90 opens the supply valve 52b. This allows the processing liquid adhering to the second main surface Wb of the substrate W to be replaced from the hydrofluoric acid-containing liquid to the first rinse liquid. The processing unit 1 may supply the first rinse liquid to the first main surface Wa of the substrate W in parallel with the supply of the first rinse liquid to the second main surface Wb of the substrate W (see FIG. 5(b)).

[0083] When the hydrofluoric acid-containing liquid has been sufficiently replaced with the first rinse liquid, the control unit 90 closes the supply valves 42b and 52b. As a specific example, the control unit 90 closes the supply valves 42b and 52b when the elapsed time from the start of the discharge of the first rinse liquid reaches or exceeds a predetermined removal rinse time. The removal rinse time is set in advance to a time sufficient to replace the hydrofluoric acid-containing liquid with the first rinse liquid. The movement driver 45c moves the first rinse nozzle 4b to the standby position.

[0084] Next, the processing unit 1 rotates the substrate W and supplies the second rinse liquid to the first main surface Wa of the substrate W (Step S9: Rinse Process: Supply of Second Rinse Liquid). Specifically, the movement driver 45c moves the second rinse nozzle 4c to the processing position, and the control unit 90 opens the supply valve 42c. As a result, as shown in FIG. 8(a), the second rinse liquid is discharged from the second rinse nozzle 4c toward the first main surface Wa of the substrate W. The second rinse liquid lands on, for example, the center of the first main surface Wa of the substrate W. The second rinse liquid that has landed on the first main surface Wa of the substrate W flows radially outward due to centrifugal force caused by the rotation of the substrate W and splashes from the periphery of the substrate W. This allows the processing liquid on the first main surface Wa of the substrate W to be replaced from the first rinse liquid to the second rinse liquid. Note that in the example of FIG. 8(a), the discharger 3 does not discharge the first rinse liquid onto the second main surface Wb of the substrate W.

[0085] When the first rinse liquid has been sufficiently replaced with the second rinse liquid, the control unit 90 closes the supply valve 42c. As a specific example, the control unit 90 closes the supply valve 42c when the elapsed time from the start of the discharge of the second rinse liquid becomes equal to or exceeds a predetermined second rinse time A. The second rinse time A is preset to a time sufficient to replace the first rinse liquid with the second rinse liquid. In addition, the movement driver 45c moves the second rinse nozzle 4c to the standby position.

[0086] Next, the processing unit 1 rotates the substrate W and supplies a hydrophobizing liquid to the first main surface Wa of the substrate W (Step S10: Hydrophobizing Process: Hydrophobizing Liquid Supply). Specifically, the movement driver 45a moves the hydrophobizing nozzle 4a to the processing position, and the control unit 90 opens the supply valve 42a. As a result, as shown in FIG. 8(b), the hydrophobizing liquid is discharged from the hydrophobizing nozzle 4a toward the first main surface Wa of the substrate W. The hydrophobizing liquid lands on, for example, the center of the first main surface Wa of the substrate W. The hydrophobizing liquid that has landed on the first main surface Wa of the substrate W is subjected to centrifugal force accompanying the rotation of the substrate W, flows radially outward, and splashes from the periphery of the substrate W. At this time, the hydrophobizing liquid acts on the first main surface Wa of the substrate W. Specifically, the hydrophobizing liquid contains hydrophobic groups (organic substances) and replaces substituents on the substrate W with hydrophobic groups. For example, the hydrogen molecules of the hydroxyl groups present on the oxide surface of the substrate W are substituted with trimethylsilyl groups in the molecules of the hydrophobizing liquid, thereby making the first main surface Wa of the substrate W hydrophobic.

[0087] Although the hydrophobizing liquid may flow around the edge Wc of the substrate W and affect the peripheral portion of the second main surface Wb of the substrate W, most of the oxides and substituents on the peripheral portion of the second main surface Wb of the substrate W have been removed in step S7. Therefore, even if the hydrophobic groups flow along the peripheral portion of the second main surface Wb of the substrate W, the peripheral portion of the second main surface Wb of the substrate W is hardly hydrophobized. In other words, the phenomenon in which the substituents of the substrate W are replaced by hydrophobic groups (organic substances) in the molecules of the hydrophobizing liquid hardly occurs. Therefore, even after treatment with the hydrophobizing liquid, the peripheral portion of the second main surface Wb of the substrate W contains almost no organic substances (hydrophobic groups).

[0088] When the oxides and substituents on the edge surface Wc of the substrate W are almost completely removed by step S7, the edge surface Wc of the substrate W is also hardly hydrophobized. In other words, even after the treatment with the hydrophobizing liquid, the peripheral portion of the edge surface Wc of the substrate W contains almost no organic matter (hydrophobic groups).

[0089] As described above, the processing unit 1 can hydrophobize the first main surface Wa of the substrate W while avoiding hydrophobization of the second main surface Wb and further the edge surface We of the substrate W.

[0090] In the example of FIG. 8(b), the discharge part 3 does not discharge the first rinsing liquid onto the second main surface Wb of the substrate W.

[0091] When the first main surface Wa of the substrate W has been sufficiently hydrophobized, the control unit 90 closes the supply valve 42a. As a specific example, the control unit 90 closes the supply valve 42a when the elapsed time from the start of the discharge of the hydrophobizing liquid reaches or exceeds a predetermined hydrophobization time. The hydrophobization time is set in advance to a time sufficient to sufficiently hydrophobize the first main surface Wa of the substrate W. In addition, the movement drive unit 45a moves the hydrophobization nozzle 4a to the standby position.

[0092] Next, the processing unit 1 rotates the substrate W and supplies a second rinse liquid to the first main surface Wa of the substrate W (step S11: rinsing step: supply second rinse liquid). This allows the processing liquid on the first main surface Wa of the substrate W to be replaced from the hydrophobizing liquid to the second rinse liquid. As an example, the discharge part 3 does not discharge the first rinse liquid onto the second main surface Wb of the substrate W.

[0093] When the hydrophobization liquid has been sufficiently replaced with the second rinse liquid, the control unit 90 closes the supply valve 42c. As a specific example, the control unit 90 closes the supply valve 42c when the elapsed time from the start of the discharge of the second rinse liquid is equal to or longer than a predetermined second rinse time. The second rinse time is set in advance to a time sufficient to replace the hydrophobization liquid with the second rinse liquid. In addition, the movement driver 45c moves the second rinse nozzle 4c to the standby position.

[0094] In step S11, the discharge unit 3 may supply a mixed liquid of isopropyl alcohol and pure water (diluted IPA) to the first main surface Wa of the substrate W. In this case, the second rinse nozzle 4c is connected to a pure water supply source through a branch pipe (not shown), and a supply valve (not shown) and a flow rate adjustment valve (not shown) are inserted in the branch pipe.

[0095] Next, the processing unit 1 dries the substrate W (step S12: drying step). For example, the substrate holder 2 increases the rotation speed of the substrate W (so-called spin drying). This dries the substrate W.

[0096] Next, the substrate holding part 2 releases the hold of the substrate W (step S13: hold release step). For example, the substrate holding part 2 moves each chuck pin 22 from the holding position to the release position. This releases the hold of the substrate W. Next, the second transport part 122 carries the substrate W out of the processing unit 1.

[0097] As described above, the processing unit 1 can perform a series of processes on the substrate W. For example, the processing unit 1 can remove a native oxide film on the first main surface Wa of the substrate W using a first chemical liquid (step S3), while removing impurities such as particles on the first main surface Wa of the substrate W after the native oxide film has been removed using a second chemical liquid (step S5). In addition, the second chemical liquid can form an oxide film (more specifically, a substituent) required for hydrophobization on the first main surface Wa of the substrate W.

[0098] Furthermore, before supplying the hydrophobizing liquid to the first main surface Wa of the substrate W (step S10), the processing unit 1 supplies a hydrofluoric acid-containing liquid to the second main surface Wb of the substrate W (step S7). Therefore, by the time the hydrophobizing liquid is supplied, oxides and substituents on the peripheral portion of the second main surface Wb of the substrate W have almost been removed. Therefore, even if the hydrophobizing liquid reaches the peripheral portion of the second main surface Wb of the substrate W, the peripheral portion of the second main surface Wb is hardly hydrophobized. In other words, almost no hydrophobic groups (organic substances) adhere to the peripheral portion of the second main surface Wb of the substrate W.

[0099] In step S7, when the hydrofluoric acid-containing liquid reaches the entire edge surface Wc of the substrate W, oxides and substituents can be almost completely removed from the entire edge surface Wc of the substrate W. Therefore, even if the hydrophobizing liquid reaches the edge surface Wc of the substrate W in step S10, the edge surface Wc of the second main surface Wb is hardly hydrophobized. In other words, almost no hydrophobic groups (organic substances) adhere to the edge surface Wc of the substrate W.

[0100] On the other hand, in step S10, an oxide film remains formed on the first main surface Wa (specifically, the device region Wa1) of the substrate W. Therefore, while the first main surface Wa of the substrate W is hydrophobized by the hydrophobizing liquid, hydrophobization of the second main surface Wb and even the end surface We of the substrate W can be largely avoided.

[0101] When the hydrophobized substrate W is dried, the contact angle of the second rinse liquid between the patterns on the first main surface Wa is close to 90 degrees because the first main surface Wa is a hydrophobic surface. This reduces the possibility that the patterns on the first main surface Wa of the substrate W will collapse when dried.

[0102] Furthermore, according to this substrate processing method, as described above, almost no hydrophobic groups (organic substances) adhere to the second main surface Wb of the substrate W. Therefore, when the hand of the second transport part 122 comes into contact with the second main surface Wb of the processed substrate W, there is little possibility of organic contamination of the hand. Therefore, it is possible to reduce the possibility of organic contamination being transmitted to multiple substrates W via the hand.

[0103] In the above-described specific example, almost no hydrophobic groups (organic substances) adhere to the edge Wc of the substrate W. Therefore, when the substrate W is loaded into the carrier C, even if the edge Wc of the substrate W comes into contact with the inner surface of the carrier C, there is little possibility that the carrier C will be contaminated with organic substances. This also reduces the possibility of organic contamination being transmitted between multiple substrates W via the carrier C.

[0104] In the above example, the first main surface Wa of the substrate W is oxidized with the second chemical liquid (oxidizing liquid) in step S5. As a result, an oxide film is formed on the first main surface Wa of the substrate W with a controlled film thickness, etc. This makes it possible to form an oxide film suitable for hydrophobization. After the oxide film is formed, the oxide on the second main surface Wb of the substrate W is removed with a hydrofluoric acid-containing liquid (step S7). This reduces the possibility of organic matter adhering to the second main surface Wb of the substrate W, or even to the end surface We.

[0105] In the above example, the first rinse liquid is supplied to the first main surface Wa of the substrate W in parallel with the supply of the hydrofluoric acid-containing liquid (see FIG. 7(a)). This reduces the possibility of particles adhering to the first main surface Wa of the substrate W.

[0106] Although the substrate holder 2 continues to rotate the substrate W in each step described below, the rotation of the substrate W may be temporarily stopped at each step as appropriate.

[0107] Second Embodiment 9 is a diagram schematically illustrating an example of the configuration of a processing unit 1 according to the second embodiment. The processing unit 1 according to the second embodiment differs from the processing unit 1 according to the first embodiment in the specific configurations of the substrate holder 2 and the discharge unit 3.

[0108] In the example of FIG. 9, the substrate holder 2 includes a spin base 21 and a rotation driver 23, but does not include chuck pins 22. The spin base 21 is a suction stage. The spin base 21 has a plate-like shape, and the substrate W is placed on its upper surface. A plurality of suction ports (not shown) are formed and distributed on the upper surface of the spin base 21. Each suction port is connected to a suction unit (not shown) through the internal flow of the spin base 21. The suction unit includes, for example, a pump, and sucks gas through the suction ports. As a result, the second main surface Wb of the substrate W is suctioned onto the upper surface of the spin base 21.

[0109] The spin base 21 has a circular shape in a plan view, and its diameter is smaller than the diameter of the substrate W. In other words, the substrate W protrudes outward from the spin base 21 in a plan view. Hereinafter, the portion of the substrate W that protrudes outward from the spin base 21 will be referred to as the protruding portion.

[0110] The lower surface nozzle 5 of the discharge unit 3 is provided at a position vertically facing the protruding portion of the substrate W held by the substrate holding unit 2. The lower surface nozzle 5 is horizontally adjacent to the substrate holding unit 2. The lower surface nozzle 5 discharges the hydrofluoric acid-containing liquid toward the peripheral edge of the substrate W. The lower surface nozzle 5 deposits the hydrofluoric acid-containing liquid at the same liquid landing position as the innermost position on the second main surface Wb of the substrate W into which the second chemical liquid (oxidizing liquid) wraps, or at a liquid landing position radially inward from that position. In other words, the lower surface nozzle 5 is provided at a position where the hydrofluoric acid-containing liquid can be deposited at that liquid landing position.

[0111] An example of the operation of the processing unit 1 in the second embodiment is the same as that in the first embodiment. However, the processing liquid (hydrofluoric acid-containing liquid or first rinse liquid) from the lower surface nozzle 5 is supplied to the peripheral portion of the second main surface Wb of the substrate W. This also allows the hydrofluoric acid-containing liquid to remove oxides formed by the second chemical liquid on the peripheral portion of the second main surface Wb.

[0112] As described above, the substrate processing apparatus 100 and the substrate processing method have been described in detail. However, the above description is merely an example in all respects, and this disclosure is not limited thereto. Furthermore, the various modifications described above can be applied in combination as long as they are not mutually contradictory. Furthermore, it is understood that many modifications not exemplified can be envisioned without departing from the scope of this disclosure. [Explanation of symbols]

[0113] S1 Holding process (step) S5 Chemical process (step) S6 Chemical rinse process (step) S7 Removal process (step) S8 Removal and rinsing process (step) S10 Hydrophobization step W substrate Wa First principal surface Wb 2nd principal surface Wc end face

Claims

1. a holding step of holding a substrate having a first main surface and a second main surface; a removing step of rotating the substrate and supplying a hydrofluoric acid-containing liquid containing hydrofluoric acid onto the second main surface of the substrate; a removal and rinsing step of rotating the substrate and supplying a rinsing liquid to the second main surface of the substrate after the removing step; a hydrophobizing step of rotating the substrate and supplying a hydrophobizing liquid to the first main surface of the substrate after the removing and rinsing step; A substrate processing method comprising:

2. 2. The substrate processing method according to claim 1, a chemical step, which is performed before the removing step, of rotating the substrate and supplying a chemical solution to the first main surface of the substrate to form an oxide on the first main surface of the substrate; a chemical rinse step that is performed between the chemical step and the removing step, and that rotates the substrate and supplies a rinse liquid to the first main surface of the substrate; Furthermore, In the removal step, the oxides generated in the chemical step by the chemical solution flowing from the edge face of the substrate to the second main surface and acting on the second main surface are removed by the hydrofluoric acid-containing liquid.

3. 3. The substrate processing method according to claim 2, A substrate processing method, in which, in the chemical process, the chemical is supplied to the first main surface of the substrate while rotating the substrate so that a liquid film of the chemical covers the entire first main surface of the substrate, which is hydrophobic.

4. 4. A substrate processing method according to claim 1, further comprising: In the removing step, the hydrofluoric acid-containing liquid is supplied to the second main surface of the substrate while rotating the substrate, and the hydrofluoric acid-containing liquid is allowed to flow from the end surface of the substrate to the peripheral portion of the first main surface.

5. 4. A substrate processing method according to claim 1, further comprising: a rinsing liquid being supplied to the first main surface of the substrate in parallel with the supply of the hydrofluoric acid-containing liquid to the second main surface of the substrate in the removing step.

6. a holding step of holding a substrate having a first main surface and a second main surface; a removing step of rotating the substrate and supplying a remover that removes oxides to the second main surface of the substrate; a removal and rinsing step of rotating the substrate and supplying a rinsing liquid to the second main surface of the substrate after the removing step; a hydrophobizing step of rotating the substrate and supplying a hydrophobizing liquid to the first main surface of the substrate after the removing and rinsing step; A substrate processing method comprising:

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