Substrate processing method

Abstract

A substrate processing method is provided that can reduce the possibility of a substrate being contaminated by organic matter. [Solution] A substrate processing method includes a holding step, a removing step, a removing and 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 containing hydrofluoric acid is supplied to the second main surface of the substrate. In the removing and rinsing step, after the removing step, the substrate is rotated, and a rinsing liquid is supplied to the second main surface of the substrate. In the hydrophobizing step, after the removing and rinsing step, the substrate is rotated, and a hydrophobizing liquid is supplied to the first main surface of the substrate.

Description

Technical Field

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

Background Art

[0002] Conventionally, a single-wafer substrate processing apparatus for processing a substrate has been disclosed (for example, Patent Document 1). In Patent Document 1, after hydrophobizing the surface of the substrate with a hydrophobizing liquid, the hydrophobizing liquid on the substrate is rinsed off with a rinsing liquid, and then the substrate is dried. Thereby, collapse of the pattern on the substrate during drying is suppressed.

Prior Art Documents

Patent Documents

[0003] [[ID=二十二]]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a hydrophobizing liquid is supplied to the surface of the substrate, a part of the hydrophobizing liquid wraps around the end face of the substrate and also acts on the peripheral portion of the back surface of the substrate. Therefore, the peripheral portion of the back surface of the substrate is also hydrophobized. Hydrophobization is realized by substituting the substituents on the surface of the substrate with hydrophobic groups (organic substances). That is, organic substances are present on the peripheral portion of the back surface of the processed substrate. Since the peripheral portion of the back surface of the processed substrate comes into contact with the hand of the transfer robot, there is a risk that the organic substances on the peripheral portion of the back surface adhere to the hand. That is, there is a risk of contaminating the hand. Further, when the contaminated hand picks up another substrate, there is a risk of contaminating the other substrate. [[ID=三十]]

[0005] Therefore, an object of the present disclosure is to provide a substrate processing method capable of reducing the possibility that the substrate is contaminated by organic substances.

Means for Solving the Problems

[0006] ​The 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 chemical solution 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 after the chemical solution step, The substrate is rotated, and Removal solution for removing oxides The process comprises: a removal step of supplying a rinse solution to the second main surface of the substrate; a removal rinsing step of rotating the substrate and supplying a rinse solution to the second main surface of the substrate after the removal step; and a hydrophobicization step of rotating the substrate and supplying a hydrophobic solution to the first main surface of the substrate after the removal rinsing step. The first main surface has a device region where a device is formed, and in the removal step, the removal liquid is not allowed to enter the device region. .

[0007] The second aspect is a substrate processing method according to the first aspect. ,before A chemical rinsing process is performed between the chemical solution step and the removal step, rotating the substrate and supplying the rinse solution to the first main surface of the substrate. To Furthermore, in the removal step, the oxide generated in the chemical step when the chemical solution flows from the end face of the substrate to the second main surface and acts on the second main surface is the removal liquid Remove it.

[0009] The 3 The manner of is, The process comprises: 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 solution to the second main surface of the substrate to remove oxides; a removal rinsing step of rotating the substrate and supplying a rinsing solution to the second main surface of the substrate after the removal step; and a hydrophobization step of rotating the substrate and supplying a hydrophobizing solution to the first main surface of the substrate after the removal rinsing step. In the removal process, the substrate is rotated while the removal liquid The second main surface of the substrate is supplied with the removal liquid the substrate edge It wraps around from the surface to the periphery of the first main surface.

[0010] The 4 The manner of is, The process comprises: 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 solution to the second main surface of the substrate to remove oxides; a removal rinsing step of rotating the substrate and supplying a rinsing solution to the second main surface of the substrate after the removal step; and a hydrophobization step of rotating the substrate and supplying a hydrophobizing solution to the first main surface of the substrate after the removal rinsing step. In the removal process, the second main surface of the substrate removal liquid In parallel with the supply of the rinsing solution, the rinsing solution is supplied to the first main surface of the substrate. A fifth embodiment is a substrate processing method according to the third or fourth embodiment, further comprising: a chemical solution 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 solution 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 generated in the chemical solution step by the chemical solution flowing from the end face of the substrate to the second main surface and acting on the second main surface is removed with the removal solution. The sixth aspect is a substrate processing method according to the first or second aspect, wherein in the chemical solution step, the chemical solution is supplied to the first main surface of the substrate while rotating the substrate so that the liquid film of the chemical solution covers the entire surface of the first main surface of the substrate which is hydrophobic.

[0011] The 7 The manner of is, A substrate processing method according to any one of the first to sixth, wherein the removal solution includes a hydrofluoric acid-containing solution containing hydrofluoric acid. [Effects of the Invention]

[0012] 1 , 2nd and the 7 According to this embodiment, since the hydrofluoric acid-containing solution is supplied to the second main surface in the removal step, substituents on the second main surface of the substrate can be almost completely removed. Therefore, even if the hydrophobic solution flows from the edge of the substrate to the second main surface in the hydrophobication step, the second main surface is hardly hydrophobic. In other words, the possibility of substituents on the substrate being replaced by hydrophobic groups (organic matter) in the molecules of the hydrophobic solution can be reduced. In other words, the possibility of hydrophobic groups (organic matter) adhering to the second main surface of the substrate can be reduced.

[0013] The 5 According to this embodiment, the oxide film necessary for hydrophobicity can be formed on the first main surface of the substrate in the chemical solution step. Therefore, the first main surface of the substrate can be appropriately hydrophobicized in the hydrophobicity step.

[0014] The 6 In this embodiment, during the chemical solution process, the chemical solution is supplied so that it covers the entire surface of the first main surface, thereby reducing the adhesion of particles to the first main surface of the substrate. Furthermore, in order for the chemical solution to cover the entire surface of the hydrophobic first main surface, the flow rate of the chemical solution increases, and as a result, the chemical solution is more likely to flow around the edges of the substrate. Therefore, the chemical solution also acts on the edges of the substrate and the periphery of the second main surface, and oxides are formed. However, in the removal process following the chemical solution process, most of the oxides on the second main surface can be removed. Therefore, even if the hydrophobicating solution flows around the edges of the substrate during the hydrophobicization process, the possibility of the second main surface becoming hydrophobic can be reduced.

[0015] The 3 According to this embodiment, oxides on the edge surfaces of the substrate can be almost completely removed. Therefore, the possibility of the edge surfaces of the substrate becoming hydrophobic during the hydrophobicization process can be reduced. In other words, the possibility of organic matter adhering to the edge surfaces of the substrate can be reduced.

[0016] The 4 According to this embodiment, the possibility of particles adhering to the first main surface of the substrate can be reduced. [Brief explanation of the drawing]

[0017] [Figure 1] It is a plan view schematically showing an example of the configuration of a substrate processing apparatus. [Figure 2] It is a block diagram schematically showing an example of the internal configuration of a control unit. [Figure 3] It is a diagram schematically showing an example of the configuration of a processing unit according to the first embodiment. [Figure 4] It is a flowchart showing an example of the operation of a processing unit. [Figure 5] It is a diagram schematically showing an example of the state of a processing unit in each step. [Figure 6] It is a diagram schematically showing an example of the state of a processing unit in each step. It is a diagram schematically showing an example of the state of a processing unit in each step. [Figure 7] [Figure 8] It is a diagram schematically showing an example of the state of a processing unit in each step. [Figure 9] It is a diagram schematically showing an example of the configuration of a processing unit according to the second embodiment.

Modes for Carrying Out the Invention

[0018] Hereinafter, embodiments will be described in detail with reference to the drawings. In the drawings, for the purpose of easy understanding, the dimensions and numbers of each part are exaggerated or simplified as necessary. Also, parts having the same configuration and function are denoted by the same reference numerals, and redundant explanations are omitted in the following description. <00001i17>

[0019] Also, in the descriptions shown below, the same reference numerals are attached to and illustrated for the same components, and their names and functions are also assumed to be the same. Therefore, detailed descriptions thereof may be omitted to avoid duplication.

[0020] Furthermore, even if ordinal numbers such as "first" or "second" are used in the following descriptions, these terms are used for convenience to facilitate understanding 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 are used (e.g., "in one direction," "along one direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.), unless otherwise specified, such expressions shall 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 tolerance or a range in which equivalent functionality is obtained. When expressions indicating equality are used (e.g., "identical," "equal," "homogeneous," etc.), unless otherwise specified, such expressions shall not only strictly represent a state in which there is a quantitatively exact equality but also represent a state in which there is a difference within a tolerance or a range in which equivalent functionality is obtained. When expressions indicating shape are used (e.g., "quadrilateral" or "cylindrical"), unless otherwise specified, such expressions shall not only strictly represent the geometrically exact shape but also represent a shape with, for example, irregularities or chamfers within a range in which equivalent effects are obtained. When expressions such as "equip," "possess," "feature," "include," or "have" a single component are used, such expressions are not exclusive expressions that exclude the existence of other components. When the expression "at least one of A, B, and C" is used, it 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 the substrate processing equipment> Figure 1 is a schematic plan view showing an example of the configuration of the substrate processing apparatus 100. The substrate processing apparatus 100 is a single-wafer processing apparatus that processes substrates W one at a time.

[0023] The substrate W is, for example, a semiconductor wafer, a substrate for liquid crystal displays, an organic electroluminescence (EL) substrate, a flat panel display (FPD) 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 shape. Hereinafter, the two 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, it will be assumed that the substrate W is a semiconductor wafer. The substrate W may be, for example, a silicon semiconductor. The substrate W has, for example, a disc shape. The diameter of the substrate W is, for example, about 300 mm, and the thickness of the substrate W is, for example, about 0.5 mm or more and about 3 mm or less. A pattern is formed on the first main surface Wa of the substrate W. The pattern here includes, for example, a semiconductor pattern.

[0024] In the example shown in Figure 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 primarily responsible for processing the substrate W, while the indexer block 110 is primarily responsible for transporting the substrate 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 section 112. A substrate carrier (hereinafter referred to as a carrier) C, which is brought in from the outside, is placed on the load port 111. Multiple substrates W are housed in the carrier C, for example, arranged with spacing between them in the vertical direction. In the example shown in Figure 1, multiple load ports 111 are arranged.

[0026] The first transport unit 112 is a transport robot capable of removing unprocessed substrates W from carriers 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 substrates W removed from the carriers C to the processing block 120. The processing block 120 can process the unprocessed substrates W. The first transport unit 112 can also receive processed substrates W from the processing block 120 and transport the processed substrates W to the carriers C on the load ports 111.

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

[0028] In the example shown in Figure 1, multiple (for example, four) processing units 1 are arranged to surround the second transport unit 122 in a plan view. This second transport unit 122 may also be called a center robot. At each position in the plan view, multiple processing units 1 may be stacked vertically. In other words, multiple (four in the figure) towers TW, each composed of multiple processing units 1 stacked vertically, may be arranged to surround the second transport unit 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. Figure 2 is a schematic block diagram showing 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 in Figure 2, the data processing unit 91 and the storage unit 92 are interconnected via a bus 93. The data processing unit 91 may be, for example, an arithmetic processing unit such as a CPU (Central Processor Unit). The storage unit 92 may include a non-temporary storage unit (e.g., ROM (Read Only Memory)) 921 and a temporary storage unit (e.g., RAM (Random Access Memory)) 922. The non-temporary storage unit 921 may store, for example, a program that defines the processing to be executed by the control unit 90. By executing this program, the data processing unit 91 enables the control unit 90 to execute 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 dedicated logic circuits.

[0030] <Overview of the processing unit> Figure 3 is a schematic diagram showing an example of the configuration of a processing unit 1 according to the first embodiment. Note that not all processing units 1 belonging to the substrate processing apparatus 100 need to have the configuration exemplified in Figure 3. It is sufficient that at least one processing unit 1 of the substrate processing apparatus 100 has the configuration exemplified in Figure 3.

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

[0032] In the example shown in 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 the processing space for processing the substrate W. The chamber 10 is provided with an openable and closable discharge port (not shown). The second transport unit 122 transports unprocessed substrates W into the chamber 10 through the discharge port and discharges processed substrates W from the chamber 10 through the discharge port.

[0033] The substrate holder 2 is located inside the chamber 10 and holds the substrate W in a horizontal position while rotating the substrate W around the rotation axis Q1. The horizontal position here refers to the position where 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] Here, the first main surface Wa of the substrate W on which the pattern is formed is facing vertically upward. In other words, in the example in Figure 3, the first main surface Wa of the substrate W held by the substrate holder 2 corresponds to the top surface, and the second main surface Wb of the substrate W corresponds to the bottom surface.

[0035] In the example shown in Figure 3, the substrate holder 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 disc shape) and is positioned so that its thickness direction is aligned with the vertical direction. Multiple chuck pins 22 are provided on the upper surface of the spin base 21. The multiple chuck pins 22 are provided at equal intervals along the circumferential direction with respect to the rotation axis Q1. The multiple chuck pins 22 are provided so as to be displaceable between the holding position and the release position, which will be described below. The holding position is the position in which the chuck pins 22 contact the periphery of the substrate W. The multiple chuck pins 22 hold the substrate W by stopping at their respective holding positions. Figure 3 shows the chuck pins 22 stopped at the holding position. The release position is the position in which each chuck pin 22 is separated from the substrate W. The multiple chuck pins 22 release the substrate W by stopping at their respective release positions. The substrate holding section 2 also includes a pin drive section (not shown) that displaces the chuck pin 22. The pin drive section includes, for example, a drive source such as a motor and an air cylinder, and is controlled by the control section 90.

[0036] The rotary 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 the rotation axis Q1. The motor 232 is controlled by the control unit 90 and rotates the shaft 231 around the rotation axis Q1. As a result, the spin base 21, chuck pin 22, and substrate W rotate together around the rotation axis Q1.

[0037] Note that the substrate holding part 2 does not necessarily need to have chuck pins 22. For example, the substrate holding part 2 may hold the substrate W using a chuck method such as a vacuum chuck, an electrostatic chuck, or a Bernoulli chuck.

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

[0039] In the example shown in Figure 3, the discharge unit 3 includes at least one upper nozzle 4 and at least one lower nozzle 5. Each of the upper nozzle 4 and the lower nozzle 5 is, for example, a straight nozzle that discharges a columnar liquid.

[0040] In the example shown in Figure 3, the discharge section 3 includes a hydrophobic nozzle 4a as an example of an upper nozzle 4. The hydrophobic nozzle 4a is located above the substrate W held by the substrate holding section 2 within the chamber 10. The hydrophobic nozzle 4a discharges the hydrophobic solution toward the first main surface Wa of the substrate W. The hydrophobic solution is a liquid that hydrophobicizes the surface of the substrate W. The hydrophobic solution is, for example, a silylation solution containing a liquid silylation agent (also called a silane coupling agent). The silylation agent includes, for example, HMDS (hexamethyldisilazane). The hydrophobic solution is 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). Hydroxyl groups are hydrophilic groups. The hydrophobic groups are organic hydrophobic groups contained in the molecules of the hydrophobic solution, such as a trimethylsilyl group. In this case, the hydrogen molecules of the hydroxyl groups present on the surface of the substrate W are replaced by trimethylsilyl groups, thereby making the surface of the substrate W hydrophobic.

[0041] In the example shown in Figure 3, the discharge section 3 includes a supply pipe 41a, a supply valve 42a, and a flow control valve 43a. The downstream end of the supply pipe 41a is connected to a hydrophobic nozzle 4a, and the upstream end of the supply pipe 41a is connected to a hydrophobic liquid supply source. The hydrophobic liquid supply source includes, for example, a tank for storing the hydrophobic liquid. The supply valve 42a and the flow control valve 43a are interposed in the supply pipe 41a. The supply valve 42a switches the supply pipe 41a open and closed, and the flow control valve 43a adjusts the flow rate of the hydrophobic liquid flowing through the supply pipe 41a. The supply valve 42a and the flow control valve 43a are controlled by the control unit 90.

[0042] In the example shown in Figure 3, the hydrophobic nozzle 4a is movably mounted by a moving drive unit 45a. The moving 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 the position where the hydrophobic nozzle 4a discharges the hydrophobic liquid, and is, for example, a position perpendicular to the center of the substrate W. In the example shown in 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 discharge the hydrophobic liquid, and is, for example, a position radially outside the substrate W.

[0043] Figure 3 shows an example of the specific configuration of the mobile drive unit 45a. In the example in Figure 3, the mobile drive unit 45a includes an arm 451, a support column 452, and a drive source 453. The support column 452 is located radially outward from the guard 7 (described later) and extends vertically. The arm 451 extends horizontally, 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 and rotates 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 along the circumferential direction with respect to the central axis Q2. The support column 452 is installed such that the processing position and standby position are located on the movement trajectory of the hydrophobic nozzle 4a. Note that the mobile drive unit 45a is not necessarily limited to the configuration shown in Figure 3, and may include, for example, a linear motion mechanism such as a linear motor.

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

[0045] The lower nozzle 5 is located within the chamber 10, below the substrate W held by the substrate holder 2. The lower 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, for example, dilute hydrofluoric acid. In the example shown in Figure 3, the lower nozzle 5 is located perpendicular to the center of the substrate W. As shown in Figure 3, the lower nozzle 5 may protrude from the center of the spin base 21 of the substrate holder 2 toward the second main surface Wb of the substrate W.

[0046] In the example shown in Figure 3, the discharge section 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 bottom nozzle 5, and the upstream end of the supply pipe 51a is connected to a hydrofluoric acid-containing liquid supply source. In the example shown in Figure 3, a through hole is formed in the center of the spin base 21 of the substrate holding section 2, and the shaft 231 is a hollow shaft. A portion of the supply pipe 51a extends vertically along the through hole in the spin base 21 and the hollow portion of the shaft 231. The hydrofluoric acid-containing liquid supply source includes, for example, a tank for storing the hydrofluoric acid-containing liquid. The supply valve 52a and the flow rate control valve 53a are interposed in the supply pipe 51a. The supply valve 52a switches the supply pipe 51a open and closed, 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] In the example shown in Figure 3, the discharge unit 3 is capable of discharging a treatment liquid different from the hydrophobic solution and the hydrofluoric acid-containing solution toward the substrate W. Specifically, the discharge unit 3 includes, as an example of an upper nozzle 4, a first rinse nozzle 4b, a second rinse nozzle 4c, a first chemical solution nozzle 4d, and a second chemical solution nozzle 4e.

[0048] The first chemical nozzle 4d is located within the chamber 10, above the substrate W held by the substrate holding unit 2. In the example shown in Figure 3, the first chemical nozzle 4d is movably provided by a moving drive unit 45d. The moving drive unit 45d moves the first chemical nozzle 4d between a processing position and a standby position. The processing position is the position where the first chemical nozzle 4d discharges the first chemical, for example, a position perpendicular to the center of the substrate W. The processing positions for the other top nozzles 4 are similar. The standby position is the position where the first chemical nozzle 4d does not discharge the first chemical, for example, a position radially outside the substrate holding unit 2. The standby positions for the other top nozzles 4 are similar. The moving drive unit 45d has a configuration similar to, for example, the moving drive unit 45a.

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

[0050] The second chemical nozzle 4e is located within the chamber 10, above the substrate W held by the substrate holding unit 2. In the example shown in Figure 3, the second chemical nozzle 4e is movably provided by a moving drive unit 45e. The moving drive unit 45e moves the second chemical nozzle 4e between a processing position and a standby position. The moving drive unit 45e has a configuration similar to, for example, the moving drive unit 45a.

[0051] With the second chemical nozzle 4e positioned in the processing location, it discharges the second chemical solution toward the first main surface Wa of the substrate W. The second chemical solution is, for example, a liquid that forms oxides on the substrate W. The second chemical solution is, for example, a mixture of ammonium hydroxide, hydrogen peroxide, and water (i.e., SC1). When the second chemical solution is SC1, impurities such as particles can be removed from the first main surface Wa of the substrate W.

[0052] The first rinse nozzle 4b is positioned within the chamber 10 above the substrate W held by the substrate holding unit 2. In the example shown in Figure 3, the first rinse nozzle 4b is movably mounted by a moving drive unit 45b. The moving drive unit 45b moves the first rinse nozzle 4b between a processing position and a standby position. The moving drive unit 45b has a configuration similar to, for example, the moving drive unit 45a.

[0053] With the first rinse nozzle 4b positioned in the processing location, it discharges the first rinse solution toward the first main surface Wa of the substrate W. The first rinse solution is, for example, pure water (i.e., deionized water). For example, after the discharge unit 3 discharges the first chemical solution toward the substrate W from the first chemical solution nozzle 4d, the first rinse solution is discharged toward the substrate W from the first rinse nozzle 4b. This allows the first chemical solution on the first main surface Wa of the substrate W to be washed away by the first rinse solution. In other words, the processing solution on the first main surface Wa of the substrate W can be replaced from the first chemical solution to the first rinse solution. Even after supplying the second chemical solution to the substrate W, the first rinse nozzle 4b discharges the first rinse solution toward the first main surface Wa of the substrate W. This allows the processing solution on the first main surface Wa of the substrate W to be replaced from the second chemical solution to the first rinse solution.

[0054] The second rinse nozzle 4c is located within the chamber 10, above the substrate W held by the substrate holding unit 2. In the example shown in Figure 3, the second rinse nozzle 4c is movably provided by a moving drive unit 45c. The moving drive unit 45c moves the second rinse nozzle 4c between a processing position and a standby position. The moving drive unit 45c has a configuration similar to, for example, the moving drive unit 45a.

[0055] With the second rinse nozzle 4c positioned in the processing location, it discharges the 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. An example of the organic solvent is isopropyl alcohol. For example, after the discharge unit 3 discharges the first rinse liquid toward the substrate W from the first rinse nozzle 4b, the second rinse liquid is discharged toward the substrate W from the second rinse nozzle 4c. 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.

[0056] In the example shown in Figure 3, the discharge section 3 includes a supply pipe 41b, a supply valve 42b, and a flow control valve 43b for the first rinse nozzle 4b; a supply pipe 41c, a supply valve 42c, and a flow control valve 43c for the second rinse nozzle 4c; a supply pipe 41d, a supply valve 42d, and a flow control valve 43d for the first chemical nozzle 4d; and a supply pipe 41e, a supply valve 42e, and a flow control valve 43e for the second chemical nozzle 4e. The positional relationship of these is the same as that of the hydrophobic nozzle 4a, the supply pipe 41a, the supply valve 42a, and the flow control valve 43a.

[0057] In the above example, although a moving drive unit is provided for each top nozzle 4, a moving drive unit that moves multiple top nozzles 4 may also be provided. Furthermore, although individual top nozzles 4 are provided for each processing liquid in the above example, a top nozzle 4 that is used for multiple processing liquids may also be provided.

[0058] In the example shown in Figure 3, the lower nozzle 5 of the discharge section 3 is capable of discharging the first rinse liquid. In the example shown in Figure 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 section 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 the hydrofluoric acid-containing liquid supply source, and the upstream end of the second branch pipe 50b is connected to the first rinse liquid supply source. The common pipe 50 and the first branch pipe 50a form the supply pipe 51a, and the common pipe 50 and the second branch pipe 50b form the supply pipe 51b. The supply pipe 51b connects the lower nozzle 5 to the first rinse liquid supply source.

[0059] The supply valve 52a and the flow control valve 53a are interposed in the first branch pipe 50a. The supply valve 52b and the flow control valve 53b are interposed in the second branch pipe 50b. The supply valve 52b switches the supply pipe 51b open and closed, and the flow control valve 53b adjusts the flow rate of the second rinse liquid flowing through the supply pipe 51b. The supply valve 52b and the flow control valve 53b are controlled by the control unit 90.

[0060] In the example shown in Figure 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 holding portion 2. The guard 7 can catch various processing liquids that splash from the periphery of the substrate W. The processing liquid flows down along the inner surface of the guard 7. The processing liquid is discharged to the outside of the chamber 10 through a discharge pipe (not shown) provided at the bottom of the guard 7.

[0061] <Example of operation of substrate processing equipment> Next, an example of the operation of the processing unit 1 (i.e., the substrate processing method) will be described. Figure 4 is a flowchart illustrating an example of the operation of the processing unit 1. The control unit 90 causes the processing unit 1 to execute the processes from step S1 to step S13 according to a pre-set processing procedure (recipe). Figures 5 to 8 are schematic diagrams showing an example 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 multiple chuck pins 22 from their respective release positions to holding positions. As a result, the multiple chuck pins 22 hold the substrate W. The substrate holding unit 2 continues to hold the substrate W until the processing of 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 complete.

[0064] Next, the processing unit 1 rotates the substrate W and supplies the first chemical solution to the first main surface Wa of the substrate W (Step S3: First chemical solution process: First chemical solution supply). Specifically, first, the moving drive unit 45d moves the first chemical solution nozzle 4d to the processing position. Then, the control unit 90 opens the supply valve 42d. As a result, as shown in Figure 5(a), the first chemical solution is discharged from the first chemical solution nozzle 4d toward the first main surface Wa of the rotating substrate W. The first chemical solution lands, for example, in the central part of the first main surface Wa of the substrate W. The first chemical solution that has landed on the first main surface Wa of the substrate W flows radially outward due to the centrifugal force accompanying the rotation of the substrate W and scatters 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 at a flow rate (target value) and rotation speed (target value) such that the entire surface of the first main surface Wa of the substrate W is covered with a liquid film of the processing liquid (in this case, the first chemical solution). In other words, the flow rate (target value) of the first chemical solution and the rotation speed (target value) of the substrate W are set so that the entire surface of the first main surface Wa is covered with a liquid film of the first chemical solution. This reduces the possibility of particles adhering to the first main surface Wa of the substrate W. This also applies to each step described later in which other processing liquids are discharged.

[0066] When the first chemical solution acts on the first main surface Wa of the substrate W, a treatment corresponding to the type of first chemical solution is performed on the first main surface Wa of the substrate W. If the first chemical solution contains hydrofluoric acid, for example, the 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 substrate of the first main surface Wa of the substrate W is exposed. The substrate is, for example, silicon. After treatment with the first chemical solution, the first main surface Wa of the substrate W is, for example, hydrophobic. That is, the contact angle of the first main surface Wa of the substrate W from which the native oxide film has been removed is greater 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 onto 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 Figure 5(a), the processing unit 1 may supply the first rinse solution to the second main surface Wb of the substrate W in parallel with the supply of the first chemical solution. Specifically, the control unit 90 opens the supply valve 52b. As a result, the first rinse solution is discharged from the lower nozzle 5 toward the second main surface Wb of the rotating substrate W. The first rinse solution lands on, for example, the central part of the second main surface Wb of the substrate W. The first rinse solution that has landed on the second main surface Wb of the substrate W is affected by the centrifugal force accompanying the rotation of the substrate W and flows radially outward, scattering 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 treated with the first chemical solution, 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 discharge of the first chemical solution is equal to or greater than a predetermined first chemical solution time. The first chemical solution time is preset to a time sufficient for the treatment with the first chemical solution to be carried out. 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 greater than the first chemical solution time, the control unit 90 closes the supply valve 42d. In addition, the moving drive unit 45d moves the first chemical solution nozzle 4d to the standby position.

[0069] Next, the processing unit 1 rotates the substrate W and supplies the first rinsing liquid to the first main surface Wa of the substrate W (Step S4: First chemical rinsing process: Supply of first rinsing liquid). Specifically, first, the moving drive unit 45b moves the first rinsing nozzle 4b to the processing position. Then, the control unit 90 opens the supply valve 42b. As a result, as shown in Figure 5(b), the first rinsing liquid is discharged from the first rinsing nozzle 4b toward the first main surface Wa of the rotating substrate W. The first rinsing liquid lands on the first main surface Wa of the substrate W, for example, in the central part. The first rinsing liquid that has landed on the first main surface Wa of the substrate W is affected by the centrifugal force accompanying the rotation of the substrate W and flows radially outward, scattering from the periphery of the substrate W. At this time, the first rinsing liquid pushes the processing liquid (in this case, the first chemical solution) on the first main surface Wa of the substrate W radially outward. As a result, the processing solution on the first main surface Wa of the substrate W is replaced from the first chemical solution to the first rinsing solution.

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

[0071] When the replacement of the first chemical solution with the first rinsing solution is sufficient, 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 discharge of the first rinsing solution, and closes the supply valve 42b when the elapsed time exceeds a predetermined first chemical solution rinsing time. The first chemical solution rinsing time is preset to a time sufficient for the replacement of the first chemical solution with the first rinsing solution. After the supply valve 42b is closed, the moving drive unit 45b moves the first rinsing nozzle 4b to the standby position.

[0072] Next, the processing unit 1 rotates the substrate W and supplies the second chemical solution to the first main surface Wa of the substrate W (Step S5: Second chemical solution process: Supply of second chemical solution (oxidizing solution)). Specifically, the moving drive unit 45e moves the second chemical solution nozzle 4e to the processing position, and the control unit 90 opens the supply valve 42e. As a result, as shown in Figure 6(a), the second chemical solution is discharged from the second chemical solution nozzle 4e toward the first main surface Wa of the rotating substrate W. The second chemical solution lands, for example, in the central part of the first main surface Wa of the substrate W. The second chemical solution that has landed on the first main surface Wa of the substrate W flows radially outward due to the centrifugal force accompanying the rotation of the substrate W and scatters from the periphery of the substrate W. At this time, the second chemical solution acts on the first main surface Wa of the substrate W, and chemical treatment according to the type of second chemical solution is performed on the first main surface Wa of the substrate W. The second chemical solution is a liquid that has the effect of oxidizing the surface of the substrate W. Therefore, the second chemical solution can also be described as an oxidizing solution. When the second chemical solution is SC1, the processing unit 1 can also remove impurities such as particles from the first main surface Wa of the substrate W.

[0073] The control unit 90 controls the flow rate adjustment valve 43e and the substrate holding unit 2 at a flow rate (target value) and rotation speed (target value) such that the entire surface of the first main surface Wa of the substrate W is covered with a liquid film of the processing solution (in this case, the second chemical solution). In other words, the flow rate (target value) of the second chemical solution and the rotation speed (target value) of the substrate W are set so that the entire surface of the first main surface Wa is covered with a liquid film of the second chemical solution. 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 solution is set to be relatively large. As a result, as shown in Figure 6(b), the second chemical solution can easily flow around the edge Wc of the substrate W, and the second chemical solution can also act on the edges of the edge Wc and the second main surface Wb of the substrate W. As a result, the edges of the edge Wc and the second main surface Wb of the substrate W can also be oxidized.

[0074] As described above, treatment with the second chemical solution forms an oxide film on the first main surface Wa of the substrate W, and an oxide film may also be formed on the edge Wc of the substrate W and on the peripheral edges of the second main surface Wb. The oxide film is, for example, a silicon oxide film. On the surface of this oxide film, there are OH groups that are substituents used for hydrophobization, which will be described later.

[0075] As shown in Figure 6(a), the processing unit 1 may supply the first rinse solution to the second main surface Wb of the substrate W in parallel with the supply of the second chemical solution. Specifically, the control unit 90 opens the supply valve 52b. As a result, the first rinse solution is discharged from the lower nozzle 5 toward the second main surface Wb of the rotating substrate W. The first rinse solution flows radially outward along the second main surface Wb of the substrate W and scatters 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. In addition, the first rinse solution pushes the second chemical solution that has wrapped around the end face Wc of the substrate W radially outward, thus reducing the amount of the second chemical solution that has wrapped around.

[0076] When the substrate W has been sufficiently treated with the second chemical solution, 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 discharge of the second chemical solution is equal to or greater than a predetermined second chemical solution time. The second chemical solution time is preset to a time sufficient for the treatment with the second chemical solution to be carried out. In addition, the moving drive unit 45d moves the second chemical solution nozzle 4e to the standby position.

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

[0078] Once sufficient replacement of the second chemical solution with the first rinse solution has occurred, the processing unit 1 supplies 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, when the elapsed time from the start of discharge of the first rinse solution exceeds a predetermined second chemical solution rinsing time, the control unit 90 closes the supply valve 52b and opens the supply valve 52a. The second chemical solution rinsing time is preset to a time sufficient for sufficient replacement of the second chemical solution with the first rinse solution. When the supply valve 52a is opened, hydrofluoric acid-containing liquid is discharged from the lower nozzle 5 toward the second main surface Wb of the substrate W, as shown in Figure 7(a). The hydrofluoric acid-containing liquid lands on, for example, the central part 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 is affected by the centrifugal force of the substrate W and flows radially outward, scattering from the periphery of the substrate W. When the hydrofluoric acid-containing solution acts on the second main surface Wb of the substrate W, at least a portion of the oxide formed on the second main surface Wb of the substrate W is removed. More specifically, the oxide on the second main surface Wb of the substrate W is almost completely removed. The hydrofluoric acid-containing solution can also be described as a removal solution that removes oxides. Although substituents used for hydrophobization are present on the surface of the oxide, the hydrofluoric acid-containing solution removes almost all of the oxide, so the substituents can be almost completely removed from the second main surface Wb of the substrate W.

[0079] As shown in Figure 7(a), the processing unit 1 may supply the first rinsing solution to the first main surface Wa of the substrate W in parallel with supplying the hydrofluoric acid-containing solution 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 Figure 7(b), the processing unit 1 may control the flow rate control valve 43b, the flow rate control valve 53a, and the rotation drive unit 23 under processing conditions such that the hydrofluoric acid-containing liquid flows over the entire surface of the end face Wc of the substrate W. In other words, the flow rate of the first rinse liquid (target value), the flow rate of the hydrofluoric acid-containing liquid (target value), and the rotation speed of the substrate W (target value) may be set so that the hydrofluoric acid-containing liquid flows over the entire surface of the end face Wc of the substrate W. The first main surface Wa of the substrate W has a device region Wa1 on which a device is formed and a peripheral region on which no device is formed. The peripheral region is the area 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 drive unit 23 under processing conditions such that the hydrofluoric acid-containing liquid does not enter the device region Wa1, but flows over the peripheral region. This makes it possible to remove almost all of the oxide from the edge surface Wc of the substrate W.

[0081] When the oxides on the peripheral edge of the second main surface Wb of the substrate W, and furthermore, on the entire end face Wc of the substrate W, are 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 discharge of the hydrofluoric acid-containing liquid exceeds a predetermined removal time. The removal time is preset to a time sufficient to remove the oxides from the peripheral edge of the second main surface Wb and the end face Wc of the substrate W.

[0082] Next, the processing unit 1 supplies the first rinse solution to the second main surface Wb of the substrate W (Step S8: Removal rinsing process (first rinsing process): Supply of first rinse solution). Specifically, the control unit 90 opens the supply valve 52b. This allows the processing solution adhering to the second main surface Wb of the substrate W to be replaced from the hydrofluoric acid-containing solution to the first rinse solution. In parallel with supplying the first rinse solution to the second main surface Wb of the substrate W, the processing unit 1 may also supply the first rinse solution to the first main surface Wa of the substrate W (see Figure 5(b)).

[0083] When sufficient replacement of the hydrofluoric acid-containing solution with the first rinse solution has occurred, 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 discharge of the first rinse solution exceeds a predetermined removal rinse time. The removal rinse time is preset to a time sufficient for sufficient replacement of the hydrofluoric acid-containing solution with the first rinse solution. The moving drive unit 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: Rinsing process: Supply of second rinse liquid). Specifically, the moving drive unit 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 Figure 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, for example, in the central part 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 is affected by the centrifugal force accompanying the rotation of the substrate W and flows radially outward, scattering 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. In the example of Figure 8(a), the discharge unit 3 does not discharge the first rinse liquid toward the second main surface Wb of the substrate W.

[0085] When the replacement of the first rinse liquid with the second rinse liquid is sufficient, 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 discharge of the second rinse liquid exceeds a predetermined second A rinse time. The second A rinse time is preset to a time sufficient for the replacement of the first rinse liquid with the second rinse liquid. In addition, the moving drive unit 45c moves the second rinse nozzle 4c to the standby position.

[0086] Next, the processing unit 1 rotates the substrate W and supplies hydrophobic liquid to the first main surface Wa of the substrate W (Step S10: Hydrophobicization process: Hydrophobic liquid supply). Specifically, the moving drive unit 45a moves the hydrophobic nozzle 4a to the processing position, and the control unit 90 opens the supply valve 42a. As a result, as shown in Figure 8(b), hydrophobic liquid is discharged from the hydrophobic nozzle 4a toward the first main surface Wa of the substrate W. The hydrophobic liquid lands, for example, in the central part of the first main surface Wa of the substrate W. The hydrophobic liquid that has landed on the first main surface Wa of the substrate W is subjected to centrifugal force due to the rotation of the substrate W and flows radially outward, scattering from the periphery of the substrate W. At this time, the hydrophobic liquid acts on the first main surface Wa of the substrate W. Specifically, the hydrophobic liquid contains hydrophobic groups (organic matter) and replaces substituents on the substrate W with hydrophobic groups. For example, hydrogen molecules of hydroxyl groups present on the oxide surface of substrate W are replaced by trimethylsilyl groups in the molecules of the hydrophobic solution. As a result, the first main surface Wa of substrate W becomes hydrophobic.

[0087] Although the hydrophobic solution can flow around the end face Wc of the substrate W and act on the peripheral edge of the second main surface Wb of the substrate W, the oxides and substituents on the peripheral edge of the second main surface Wb of the substrate W are almost completely removed in step S7. Therefore, even if hydrophobic groups flow over the peripheral edge of the second main surface Wb of the substrate W, the peripheral edge of the second main surface Wb of the substrate W is hardly hydrophobic. In other words, the phenomenon of substituents on the substrate W being replaced by hydrophobic groups (organic matter) in the molecules of the hydrophobic solution hardly occurs. Consequently, even after treatment with the hydrophobic solution, the peripheral edge of the second main surface Wb of the substrate W contains almost no organic matter (hydrophobic groups).

[0088] If the oxides and substituents on the end face Wc of the substrate W are almost completely removed by step S7, the end face Wc of the substrate W will also not be made almost hydrophobic. In other words, even after treatment with the hydrophobic solution, the peripheral portion of the end face Wc of the substrate W will contain 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 hydrophobicization of the second main surface Wb and even the edge surface Wc of the substrate W.

[0090] In the example shown in Figure 8(b), the discharge unit 3 does not discharge the first rinse liquid onto the second main surface Wb of the substrate W.

[0091] When the first main surface Wa of the substrate W is sufficiently hydrophobic, 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 discharge of the hydrophobic liquid exceeds a predetermined hydrophobic time. The hydrophobic time is preset to a time sufficient for the first main surface Wa of the substrate W to be sufficiently hydrophobic. In addition, the moving drive unit 45a moves the hydrophobic nozzle 4a to the standby position.

[0092] Next, the processing unit 1 rotates the substrate W and supplies the second rinsing liquid to the first main surface Wa of the substrate W (Step S11: Rinsing process: Supply of second rinsing liquid). This replaces the processing liquid on the first main surface Wa of the substrate W from the hydrophobic liquid to the second rinsing liquid. As an example, the discharge unit 3 does not discharge the first rinsing liquid to the second main surface Wb of the substrate W.

[0093] When sufficient replacement of the hydrophobic liquid with the second rinsing liquid has occurred, 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 discharge of the second rinsing liquid exceeds a predetermined second B rinsing time. The second B rinsing time is preset to a time sufficient for sufficient replacement of the hydrophobic liquid with the second rinsing liquid. In addition, the moving drive unit 45c moves the second rinsing nozzle 4c to the standby position.

[0094] In step S11, the discharge unit 3 may supply a mixture 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 interposed in the branch pipe.

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

[0096] Next, the substrate holding unit 2 releases the substrate W (step S13: release step). For example, the substrate holding unit 2 moves each chuck pin 22 from the holding position to the release position. This releases the substrate W from being held. Next, the second transport unit 122 transports 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 the native oxide film from the first main surface Wa of the substrate W using the first chemical solution (step S3), and then remove impurities such as particles from the first main surface Wa of the substrate W after the native oxide film has been removed using the second chemical solution (step S5). In addition, the second chemical solution can form an oxide film (more specifically substituents) necessary for hydrophobicity on the first main surface Wa of the substrate W.

[0098] Furthermore, before supplying the hydrophobic solution to the first main surface Wa of the substrate W (step S10), the processing unit 1 supplies a hydrofluoric acid-containing solution to the second main surface Wb of the substrate W (step S7). Therefore, at the time the hydrophobic solution is supplied, the oxides and substituents on the peripheral edge of the second main surface Wb of the substrate W are almost completely removed. Consequently, even if the hydrophobic solution flows around to the peripheral edge of the second main surface Wb of the substrate W, the peripheral edge of the second main surface Wb is hardly hydrophobic. In other words, hydrophobic groups (organic matter) hardly adhere to the peripheral edge of the second main surface Wb of the substrate W.

[0099] In step S7, if the hydrofluoric acid-containing solution spreads over the entire edge Wc of the substrate W, oxides and substituents can be almost completely removed from the entire edge Wc of the substrate W. Therefore, even if the hydrophobic solution spreads over the edge Wc of the substrate W in step S10, the edge Wc of the second main surface Wb is hardly hydrophobic. In other words, hydrophobic groups (organic matter) hardly adhere to the edge Wc of the substrate W.

[0100] On the other hand, in step S10, an oxide film remains formed on the first main surface Wa of the substrate W (specifically, the device region Wa1). Therefore, while the first main surface Wa of the substrate W is made hydrophobic by the hydrophobicizing solution, the hydrophobicization of the second main surface Wb and even the edge surface Wc of the substrate W can be almost completely avoided.

[0101] During the drying of the substrate W after hydrophobicization, the contact angle of the second rinsing solution between the patterns on the first main surface Wa is close to 90 degrees. This is because the first main surface Wa is a hydrophobic surface. Therefore, the possibility of the patterns on the first main surface Wa of the substrate W collapsing during drying can be reduced.

[0102] Furthermore, according to this substrate processing method, as described above, virtually no hydrophobic groups (organic matter) adhere to the second main surface Wb of the substrate W. Therefore, when the hand of the second transport unit 122 comes into contact with the second main surface Wb of the processed substrate W, the possibility of organic contamination of the hand is low. Consequently, the possibility of organic contamination being transmitted to multiple substrates W via the hand can also be reduced.

[0103] In the specific example described above, very few hydrophobic groups (organic matter) adhere to the edge Wc of the substrate W. Therefore, when the substrate W is introduced into the carrier C, even if the edge Wc of the substrate W comes into contact with the inner surface of the carrier C, the possibility of the carrier C being contaminated with organic matter is low. This also reduces the possibility of organic matter contamination being transmitted between multiple substrates W via the carrier C.

[0104] Furthermore, in the above example, in step S5, the first main surface Wa of the substrate W is oxidized with the second chemical solution (oxidizing solution). As a result, an oxide film is formed on the first main surface Wa of the substrate W with a controlled thickness. Therefore, an oxide film suitable for hydrophobicity can be formed. 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 solution (step S7). As a result, the possibility of organic matter adhering to the second main surface Wb of the substrate W, or even to the edge surface Wc, can be reduced.

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

[0106] Although the substrate holding unit 2 continues to rotate the substrate W in each of the steps described later, the rotation of the substrate W may be temporarily paused at each step as appropriate.

[0107] <Second Embodiment> Figure 9 is a schematic diagram showing an example of the configuration of the 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 terms of the specific configuration of the substrate holding section 2 and the specific configuration of the ejection section 3.

[0108] In the example shown in Figure 9, the substrate holding unit 2 includes a spin base 21 and a rotation drive unit 23, but does not include a chuck pin 22. The spin base 21 is an adsorption stage. The spin base 21 has a plate-like shape, and the substrate W is placed on its upper surface. Multiple adsorption ports (not shown) are dispersed on the upper surface of the spin base 21. Each adsorption 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, which draws gas from the adsorption ports. As a result, the second main surface Wb of the substrate W is adsorbed onto the upper surface of the spin base 21.

[0109] The spin base 21 has a circular shape in 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 plan view. Hereafter, 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 nozzle 5 of the discharge unit 3 is positioned vertically opposite to the protruding portion of the substrate W held by the substrate holding unit 2. The lower nozzle 5 is adjacent to the substrate holding unit 2 horizontally. The lower nozzle 5 discharges the hydrofluoric acid-containing liquid toward the peripheral edge of the substrate W. The lower nozzle 5 deposits the hydrofluoric acid-containing liquid at the same deposit position as the innermost point on the second main surface Wb of the substrate W where the second chemical solution (oxidizing liquid) wraps around, or at a deposit position radially inward from that position. In other words, the lower nozzle 5 is positioned to deposit the hydrofluoric acid-containing liquid at the deposit position.

[0111] An example of the operation of the processing unit 1 in the second embodiment is the same as in the first embodiment. However, the processing liquid (hydrofluoric acid-containing liquid or first rinsing liquid) from the lower nozzle 5 is supplied to the peripheral edge of the second main surface Wb of the substrate W. In this way, the hydrofluoric acid-containing liquid can remove oxides from the peripheral edge of the second main surface Wb formed by the second chemical solution.

[0112] As described above, the substrate processing apparatus 100 and the substrate processing method have been described in detail, but the above description is illustrative 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 do not contradict each other. And it is understood that a number of modifications not illustrated can be conceivable without falling outside the scope of this disclosure. [Explanation of symbols]

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

Claims

1. A holding step for holding a substrate having a first main surface and a second main surface, A chemical solution 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, After the chemical solution step, a removal step is performed in which the substrate is rotated and a removal solution for removing oxides is supplied to the second main surface of the substrate. After the removal step, a removal rinsing step is performed in which the substrate is rotated and rinsing liquid is supplied to the second main surface of the substrate, After the removal rinsing step, a hydrophobicization step is performed in which the substrate is rotated and a hydrophobic solution is supplied to the first main surface of the substrate. Equipped with, The first main surface has a device region on which a device is formed. A substrate processing method wherein the removal step prevents the removal liquid from entering the device region.

2. A substrate processing method according to claim 1, The process further comprises a chemical rinse step, which is performed between the chemical step and the removal step, and which rotates the substrate and supplies a rinse solution to the first main surface of the substrate. A substrate processing method in which, in the removal step, the oxide generated in the chemical step when the chemical solution flows from the edge face of the substrate to the second main surface and acts on the second main surface is removed with the removal solution.

3. A holding step for holding a substrate having a first main surface and a second main surface, A removal step comprising rotating the substrate and supplying a removal solution to the second main surface of the substrate to remove oxides, After the removal step, a removal rinsing step is performed in which the substrate is rotated and rinsing liquid is supplied to the second main surface of the substrate, After the removal rinsing step, a hydrophobicization step is performed in which the substrate is rotated and a hydrophobic solution is supplied to the first main surface of the substrate. Equipped with, A substrate processing method comprising the removal step of supplying the removal liquid to the second main surface of the substrate while rotating the substrate, thereby allowing the removal liquid to flow from the end surface of the substrate to the peripheral edge of the first main surface.

4. A holding step for holding a substrate having a first main surface and a second main surface, A removal step comprising rotating the substrate and supplying a removal solution to the second main surface of the substrate to remove oxides, After the removal step, a removal rinsing step is performed in which the substrate is rotated and rinsing liquid is supplied to the second main surface of the substrate, After the removal rinsing step, a hydrophobicization step is performed in which the substrate is rotated and a hydrophobic solution is supplied to the first main surface of the substrate. Equipped with, A substrate processing method comprising supplying a rinsing solution to the first main surface of the substrate in parallel with supplying the removal solution to the second main surface of the substrate during the removal process.

5. A substrate processing method according to claim 3 or claim 4, A chemical solution 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, A chemical rinse step is performed between the chemical step and the removal step, in which the substrate is rotated and the rinse liquid is supplied to the first main surface of the substrate. Furthermore, A substrate processing method in which, in the removal step, the oxide generated in the chemical step when the chemical solution flows from the edge face of the substrate to the second main surface and acts on the second main surface is removed with the removal solution.

6. A substrate processing method according to claim 1 or claim 2, A substrate processing method comprising supplying the chemical solution to the first main surface of the substrate while rotating the substrate, in the chemical solution step, such that the liquid film of the chemical solution covers the entire surface of the first main surface of the substrate having hydrophobic properties.

7. A substrate processing method according to any one of Claims 1 to 4, The aforementioned removal solution includes a hydrofluoric acid-containing solution, wherein the substrate treatment method includes a hydrofluoric acid-containing solution.

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