Substrate processing apparatus and substrate processing method

Abstract

To provide a technology that can prevent a processing solution supplied to one main surface of a substrate from spreading to the other main surface of the substrate. [Solution] The substrate processing apparatus 100 comprises a base plate 11, a position regulating pin 13 above the base plate 11 for regulating the position of the substrate 9, a rotation mechanism 14 for rotating the base plate 11 around a rotation axis J1, a processing liquid supply unit 2 for supplying processing liquid to the upper surface of the substrate 9, a discharge passage 32 extending inside the base plate 11 from a first opening 32a provided in the base plate 11 to a second opening 32b opening toward the upper surface 111 of the base plate 11, and a gas supply unit 303 for introducing gas into the first opening 32a and discharging it from the second opening 32b. The direction K of the discharge passage 32 extending from the first opening 32a to the second opening 32b is, when viewed from above, inclined downstream of the rotation direction R of the base plate 11 with respect to a virtual straight line D passing through the rotation axis J1 and the first opening 32a.

Description

Technical Field

[0004] ,

[0006] , , ,

[0005] , , ,

[0001] This application relates to a substrate processing apparatus and a substrate processing method. <0oo0005>

Background Art

[0002] In manufacturing semiconductor devices and the like, various processes are performed on a substrate. For example, there is known a substrate processing apparatus that holds a substrate in a posture (horizontal posture) such that its thickness direction is along the vertical direction, rotates the substrate around an axis extending vertically through the center of its main surface, supplies a processing liquid to the substrate, and processes the substrate with the processing liquid (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When supplying a processing liquid to one main surface (for example, the upper - facing main surface) of a substrate while holding and rotating the substrate in a horizontal posture, there is a possibility that the processing liquid supplied to the main surface may overflow to the other main surface (for example, the lower - facing main surface). Depending on the processing recipe, it is required to suppress this overflow and keep the width of the overflow (overflow width) of the processing liquid to the other main surface small.

[0005] This application has been made in view of such problems, and its object is to provide a technology capable of suppressing the overflow of the processing liquid supplied to one main surface of the substrate to the other main surface of the substrate.

Means for Solving the Problems

[0006] The first embodiment is a substrate processing apparatus comprising: a base plate; a plurality of position regulating pins provided on the base plate for regulating the position of a substrate placed horizontally above the base plate; a rotation mechanism for rotating the base plate around a vertically extending rotation axis; a processing liquid supply unit for supplying processing liquid to the upper surface of the substrate; a discharge passage extending within the base plate from a first opening provided in the base plate to a second opening opening on the upper surface side of the base plate; and a gas supply unit for introducing gas into the first opening and discharging it from the second opening, wherein the direction of extension of the discharge passage from the first opening to the second opening is, when viewed from above, inclined downstream of the rotation direction of the base plate with respect to a virtual straight line passing through the rotation axis and the first opening.

[0007] The second embodiment is a substrate processing apparatus according to the first embodiment, wherein the extending direction, when viewed from above, moves away from the axis of rotation and is inclined downstream of the rotation direction of the base plate with respect to the virtual straight line.

[0008] The third embodiment is a substrate processing apparatus according to the second embodiment, wherein, when viewed from above, the angle between the extending direction and the virtual straight line is 45° or less.

[0009] The fourth embodiment is a substrate processing apparatus according to any of the first to third embodiments, wherein the extending direction is inclined upward while moving away from the rotation axis.

[0010] The fifth embodiment is a substrate processing apparatus according to the fourth embodiment, wherein the angle between the extending direction and the horizontal plane is 45° or less.

[0011] A sixth embodiment is a substrate processing apparatus according to the fourth or fifth embodiment, wherein the angle between the extending direction and the horizontal plane is defined such that the gas discharged from the second opening reaches a peripheral region of the substrate positioned above the base plate and whose position is restricted by the position regulating pin.

[0012] The seventh embodiment is a substrate processing apparatus according to any of the first to sixth embodiments, wherein a plurality of discharge passages are provided in the base plate, the first opening of each of the plurality of discharge passages is arranged on the circumference of a first virtual circle centered on the axis of rotation, and the second opening of each of the plurality of discharge passages is arranged on the circumference of a second virtual circle centered on the axis of rotation, having a larger diameter than the first virtual circle.

[0013] The eighth aspect is a substrate processing apparatus according to the seventh aspect, comprising a third opening that opens on the upper surface side of the base plate at a position closer to the axis of rotation than the second opening, wherein the gas supply unit supplies the gas to the third opening at a flow rate smaller than the total flow rate of the gas flowing into each of the plurality of discharge passages' first openings, and discharges the gas from the third opening.

[0014] The ninth aspect is a substrate processing method comprising: a positioning step of restricting the position of a substrate placed horizontally above a base plate with positioning pins provided on the base plate; a discharge step of guiding gas flowing in from a first opening provided on the base plate through a discharge passage to a second opening and discharging it from the second opening to the upper surface side of the base plate; a rotation step of rotating the base plate around a rotation axis extending vertically; and a processing liquid supply step of supplying a processing liquid to the upper surface of the substrate, wherein the direction of extension of the discharge passage from the first opening to the second opening is, when viewed from above, inclined downstream of the rotation direction of the base plate with respect to a virtual straight line passing through the rotation axis and the first opening. [Effects of the Invention]

[0015] According to the substrate processing apparatus of the first embodiment, the horizontal velocity component of the velocity vector of the gas discharged from the second opening that opens on the upper surface side of the base plate has a velocity component (first velocity component) that is directed downstream in the direction of rotation along the tangential direction of the circle centered on the axis of rotation. A rotating airflow is formed on the lower surface side of the rotating substrate, flowing in the direction of rotation along the circumferential direction of the circle centered on the axis of rotation. Because the gas discharged from the second opening has a first velocity component, the force of this rotating airflow is not weakened by the discharged gas, but rather strengthened. Therefore, an airflow with sufficient velocity is formed in the space between the substrate and the base plate (lower space). This prevents the processing liquid supplied to the upper surface of the substrate from flowing back to the lower surface of the substrate.

[0016] According to the substrate processing apparatus of the second embodiment, the horizontal velocity component of the velocity vector of the gas discharged from the second opening has a velocity component (second velocity component) that is directed outward along the radial direction of a circle centered on the axis of rotation. Therefore, the radial inward movement of the processing liquid on the lower surface of the substrate can be sufficiently suppressed. Consequently, the amount of leakage of the processing liquid can be kept small.

[0017] According to the substrate processing apparatus of the third embodiment, the gas discharged from the second opening has a sufficiently large second velocity component. Therefore, the width of the processing liquid leakage can be kept sufficiently small.

[0018] According to the substrate processing apparatus of the fourth embodiment, the velocity vector of the gas discharged from the second opening has a horizontal velocity component having a first velocity component and a second velocity component, and a vertical velocity component pointing vertically upward. Therefore, the processing liquid that attempts to flow from the upper surface of the substrate to the lower surface of the substrate can be pushed back radially outward and upward of the substrate. This effectively prevents the processing liquid from flowing to the lower surface of the substrate.

[0019] According to the substrate processing apparatus according to the fifth aspect, the gas discharged from the second opening has a sufficiently large horizontal velocity component. Therefore, an air flow with a sufficient flow velocity is formed in the lower space, and the processing liquid is suppressed from flowing around to the lower surface of the substrate.

[0020] According to the substrate processing apparatus according to the sixth aspect, an air flow with a sufficient flow velocity is formed in the vicinity of the peripheral region, and the processing liquid that tries to flow from the upper surface to the lower surface of the substrate can be effectively pushed back outward and upward in the radial direction of the substrate. As a result, the processing liquid can be effectively suppressed from flowing around to the lower surface of the substrate.

[0021] According to the substrate processing apparatus according to the seventh aspect, in the region outside the second virtual circle as viewed from above in the lower space, an air flow with a sufficient flow velocity is formed over the entire circumferential direction. As a result, the flowing around of the processing liquid is sufficiently suppressed over the entire circumferential direction of the substrate.

[0022] According to the substrate processing apparatus according to the eighth aspect, the flowing around of the processing liquid can be sufficiently suppressed over the entire circumferential direction of the substrate, and the lower surface of the substrate can be protected by gas.

Brief Description of the Drawings

[0023] [Figure 1] It is a side sectional view schematically showing the configuration of the substrate processing apparatus according to the embodiment. [Figure 2] It is a plan view schematically showing the upper surface of the base plate. [Figure 3] It is a plan view of the position regulating pin. [Figure 4] It is a side view schematically showing the state in which the position regulating pin is moved between the release position and the regulation position. [Figure 5] It is a side sectional view of the base plate. [Figure 6] It is a plan view showing an example of a discharge path in which the inclination angle is greater than 0° and less than or equal to 45°. [Figure 7] It is a plan view showing an example of a discharge path in which the inclination angle is greater than 45° and less than 90°. [Figure 8] This is a plan view showing an example of a discharge path with an inclination angle of 90° or more and less than 180°. [Figure 9] This is a side cross-sectional view of the base plate near the discharge passage. [Figure 10] This is a diagram illustrating the gas flow formed in the space below. [Figure 11] This is a block diagram showing the configuration of the control unit. [Figure 12] This diagram shows the processing flow performed in a substrate processing apparatus. [Figure 13] This is analytical data of the velocity distribution of the gas flow formed in the space below. [Figure 14] This diagram shows the configuration of the gas discharge section in a modified example. [Figure 15] This is a plan view showing the discharge paths for Comparative Example 2 and Comparative Example 3. [Modes for carrying out the invention]

[0024] The embodiments will be described below with reference to the attached drawings. Note that the components described in these embodiments are merely examples and are not intended to limit the scope of this disclosure to them alone. Furthermore, for ease of understanding, the dimensions or number of parts in the drawings may be exaggerated or simplified as needed.

[0025] Expressions indicating relative or absolute positional relationships (e.g., "in one direction," "along one direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.) shall, unless otherwise specified, not only strictly represent the positional relationship but also represent a state in which the object is relatively displaced in terms of angle or distance within a tolerance or range in which equivalent functionality is obtained. Similarly, expressions indicating equality (e.g., "identical," "equal," "homogeneous," etc.) shall, unless otherwise specified, not only represent a state in which the object is quantitatively exactly equal but also represent a state in which there is a difference in which tolerance or equivalent functionality is obtained. Furthermore, expressions indicating shape (e.g., "circular," "square," "cylindrical," etc.) shall, unless otherwise specified, not only strictly represent the shape geometrically but also represent a shape within a range in which equivalent effects are obtained, and may include features such as concavity or chamfers. Finally, expressions such as "equipped," "possessed," "contains," and "have" a component are not exclusive expressions that exclude the existence of other components. Furthermore, the expression "at least one of A, B, and C" includes "A only," "B only," "C only," "any two of A, B, and C," and "all of A, B, and C."

[0026] <1. Configuration of substrate processing equipment> The configuration of the substrate processing apparatus 100 according to this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a schematic side cross-sectional view showing the configuration of the substrate processing apparatus 100. Figure 2 is a schematic plan view showing the upper surface 111 of the base plate 11.

[0027] The substrate processing apparatus 100 is a so-called single-wafer processing apparatus that processes substrates 9 one at a time. The substrates 9 to be processed are, for example, disc-shaped. The substrate processing apparatus 100 comprises, for example, a spin chuck 1, a processing liquid supply unit 2, a gas discharge unit 3, and a control unit 4. The spin chuck 1, the processing liquid nozzle 21 (described later) of the processing liquid supply unit 2, etc., are housed in a chamber (not shown) that forms an approximately sealed space inside.

[0028] (Spin Chuck 1) The spin chuck 1 rotates the substrate 9 while positioning it in a horizontal orientation. Here, "horizontal orientation" refers to an orientation in which the thickness direction of the substrate 9 is aligned with the vertical direction, one main surface of the substrate 9 faces downward, and the other main surface faces upward. The spin chuck 1 comprises, for example, a base plate 11, a plurality of support pins 12, a plurality of position regulating pins 13, and a rotation mechanism 14.

[0029] The base plate 11 is a disc-shaped member and is positioned so that its thickness direction is aligned with the vertical direction. The base plate 11 is provided with a plurality of support pins 12 and a plurality of position regulating pins 13.

[0030] Multiple support pins 12 contact the substrate 9 from below, supporting the substrate 9 in a horizontal position above the base plate 11. A lifting mechanism (not shown) is connected to the multiple support pins 12 to raise and lower them (move them vertically) between an upper and lower position. As the lifting mechanism raises and lowers each support pin 12, the substrate 9 supported by the support pins 12 moves up and down. In other words, here, the multiple support pins 12 not only function as support pins that support the substrate 9, but also as lift pins that raise and lower the substrate 9.

[0031] Multiple position-regulating pins 13 contact the substrate 9, which is positioned horizontally above the base plate 11, from the side, thereby regulating the position of the substrate 9. The specific configuration of the position-regulating pins 13 will be described later.

[0032] The rotation mechanism 14 rotates the base plate 11 around an axis (rotation axis) J1 that extends vertically. For example, the axis extending vertically through the center of the upper surface 111 of the base plate 11 is defined as the rotation axis J1. As will become clear later, the substrate 9, whose position is restricted by the position restriction pins 13, has its center coincide with the rotation axis J1 when viewed from above. In other words, the rotation axis J1 passes through the center of the substrate 9 whose position is restricted by the position restriction pins 13. Specifically, the rotation mechanism 14 includes, for example, a shaft 141 that is arranged coaxially with the rotation axis J1 and connected at its upper end to the lower surface 112 of the base plate 11, and a motor 142 that rotates the shaft 141 around its axis. The rotation of the shaft 141 by the drive of the motor 142 causes the base plate 11 to rotate around the rotation axis J1. The motor 142 operates in response to instructions from the control unit 4, and the rotational speed of the base plate 11, the position (angle) of the rotational direction when the base plate 11 stops rotating, etc., are controlled by the control unit 4.

[0033] (Processing liquid supply unit 2) The processing liquid supply unit 2 supplies processing liquid to the upper surface 92 of the substrate 9 (specifically, the substrate 9 which is positioned horizontally above the base plate 11 and whose position is restricted by the position regulating pins 13). The processing liquid supply unit 2 includes, for example, a processing liquid nozzle 21 and a processing liquid supply source 22.

[0034] The processing liquid nozzle 21 is a nozzle that discharges processing liquid and is supported by a nozzle arm 211. A nozzle moving mechanism (not shown) is connected to the nozzle arm 211, and the processing liquid nozzle 21 is moved between a discharge position and a standby position when the nozzle arm 211 is driven by the nozzle moving mechanism. Here, the "discharge position" is the position where the processing liquid nozzle 21 overlaps with the substrate 9 when viewed from above (for example, a position facing the center of the upper surface 92 of the substrate 9). The "standby position" is the position where the processing liquid nozzle 21 does not overlap with the substrate 9 when viewed from above, but is spaced away from it.

[0035] The processing liquid supply source 22 is a supply source that supplies processing liquid to the processing liquid nozzle 21. Specifically, the processing liquid supply source 22 comprises, for example, a chemical supply source 22a that supplies a chemical solution as the first processing liquid to the processing liquid nozzle 21, and a rinse liquid supply source 22b that supplies a rinse liquid as the second processing liquid to the processing liquid nozzle 21. The chemical solution is, for example, hydrofluoric acid (HF), ozone-containing hydrofluoric acid solution, dilute hydrofluoric acid (DHF), buffered hydrofluoric acid (BHF), or SC1 (a liquid containing NH4OH and H2O2), but is not limited to these. The rinse liquid is, for example, deionized water (DIW) or isopropyl alcohol (IPA), but is not limited to these.

[0036] The chemical supply source 22a is connected to the processing liquid nozzle 21 via a pipe 223a in which a chemical valve 221a and a flow rate adjustment unit 222a are inserted. Therefore, when the chemical valve 221a is opened while the processing liquid nozzle 21 is in the discharge position, the chemical is discharged from the processing liquid nozzle 21 toward the substrate 9 (in this case, the upper surface 92 of the substrate 9). Similarly, the rinse liquid supply source 22b is connected to the processing liquid nozzle 21 via a pipe 223b in which a rinse liquid valve 221b and a flow rate adjustment unit 222b are inserted. Therefore, when the rinse liquid valve 221b is opened while the processing liquid nozzle 21 is in the discharge position, the rinse liquid is discharged from the processing liquid nozzle 21 toward the substrate 9 (in this case, the upper surface 92 of the substrate 9). Each valve 221a, 221b and each flow rate adjustment unit 222a, 222b operates in accordance with instructions from the control unit 4, and the timing and amount of discharge of the processed liquid are controlled by the control unit 4.

[0037] (Gas discharge section 3) The gas discharge unit 3 discharges gas into the space (lower space) U between the lower surface 91 of the substrate 9 (specifically, the substrate 9 which is positioned horizontally above the base plate 11 and whose position is restricted by the position regulating pins 13) and the upper surface 111 of the base plate 11. The specific configuration of the gas discharge unit 3 will be described later.

[0038] (Control Unit 4) The control unit 4 controls each part of the substrate processing apparatus 100 (spin chuck (substrate holding part) 1, processing liquid supply part 2, and gas discharge part 3). The control unit 4 is composed of, for example, a general computer having an electrical circuit. As an example, as shown in Figure 11, the control unit 4 is composed of a CPU (Central Processor Unit) 41 as a central processing unit responsible for data processing, a ROM (Read Only Memory) 42 in which basic programs are stored, a RAM (Random Access Memory) 43 used as a work area when the CPU 41 performs predetermined processing (data processing), a storage device 44 composed of non-volatile storage devices such as flash memory and hard disk drives, and a bus line 45 connecting these to each other. The storage device 44 stores a program P that defines the processing to be executed by the control unit 4, and by executing this program P on the CPU 41, the control unit 4 can execute the processing defined by the program P. However, some or all of the processing to be executed by the control unit 4 may be executed by dedicated hardware such as logic circuits. Also, the program P may be stored on a recording medium, and the program P may be installed on the control unit 4 using this recording medium.

[0039] <2. Positioning pin> The position regulating pin 13 provided on the base plate 11 will be explained with reference to Figures 1, 2, 3, and 4. Figure 3 is a plan view of the position regulating pin 13. Figure 4 is a schematic side view showing how the position regulating pin 13 moves between the release position P1 and the regulating position P2. In the following explanation, the annular portion in plan view surrounding the main surface of the substrate 9, which is non-parallel to each main surface that extends flat, will be referred to as the "peripheral edge 93" of the substrate 9. For example, if the diameter of the substrate 9 is 300 mm, the peripheral edge 93 is an annular region approximately 0.5 mm from the end face of the substrate 9. In example, the peripheral edge 93 is curved in an arc shape, but it is not limited to this shape.

[0040] As shown in Figure 2, multiple position regulating pins 13 (six in the example shown) are provided on the upper surface 111 of the base plate 11. The multiple position regulating pins 13 are arranged at equal intervals along the circumference of a virtual circle (reference circle) C centered on the rotation axis J1, which is defined on the upper surface 111. However, the diameter of the reference circle C is approximately the same as the diameter of the substrate 9. In other words, the circumference of the reference circle C is defined to coincide with the end face of the substrate 9 at a position where its center coincides with the rotation axis J1 (hereinafter referred to as the "normal position") when viewed from above. Multiple support pins 12 are also provided on the circumference of the reference circle C. That is, the multiple support pins 12 are arranged at equal intervals along the circumference of the reference circle C. Here, the same number of position regulating pins 13 and support pins 12 are provided, and the position regulating pins 13 and support pins 12 are arranged alternately at equal intervals along the circumference of the reference circle C.

[0041] As shown in Figures 3 and 4, the position regulating pin 13 comprises a substantially cylindrical base portion 131 and a projection portion 132 that protrudes upward from the upper end surface of the base portion 131.

[0042] The base portion 131 is positioned within a cylindrical hole 113 provided on the upper surface 111 of the base plate 11. In other words, the upper surface 111 of the base plate 11 has a plurality of holes 113 arranged at equal intervals along the circumference of a reference circle C, and the base portion 131 of each position regulating pin 13 is positioned within each hole 113. A bearing 1131 (Figure 1) is provided in the hole 113, and the base portion 131 is supported so as to be rotatable around an axis (pin rotation axis) J2 that extends vertically through its center. A locking member (not shown) may also be provided in the hole 113 to limit the rotation range of the base portion 131 to a predetermined angular range. Furthermore, it is preferable that the upper surface of the base portion 131 is positioned at the same height as the upper surface 111 of the base plate 11, or slightly above the upper surface 111. With this configuration, when processing is performed using the processing liquid, the processing liquid does not accumulate on the upper surface of the base portion 131.

[0043] The protruding portion 132 is positioned at an eccentric location (offset) from the pin rotation axis J2. A restricting surface 132d is provided on the side surface of the protruding portion 132, in the portion facing the rotation axis J1 on that side surface. Specifically, the restricting surface 132d comprises, for example, an upper surface 1321, a curved surface 1322 extending below the upper surface 1321, and a lower surface 1323 extending below the curved surface 1322. The upper surface 1321 is a flat surface region that slopes upward in a direction approaching the rotation axis J1 (i.e., its normal direction is obliquely downward). The curved surface 1322 is, for example, a curved surface with a curvature similar to that of the peripheral edge 93 of the substrate 9. The lower surface 1323 is a flat surface region that slopes downward in a direction approaching the rotation axis J1 (i.e., its normal direction is obliquely upward). The inclination angle of the lower surface 1323 is, for example, about the same as the inclination angle of the upper surface 1321.

[0044] A pin drive mechanism 133 (Figure 1) is connected to the position regulating pin 13, which rotates it around the pin rotation axis J2. That is, the position regulating pin 13 is driven by the pin drive mechanism 133 to rotate around the pin rotation axis J2. As a result, the regulating surface 132d moves in a direction toward or toward the circumference of the reference circle C (and thus toward the peripheral edge 93 of the substrate 9 in the normal position). In other words, by rotating the position regulating pin 13 around the pin rotation axis J2, the regulating surface 132d moves between a position P1 where it is relatively far from the peripheral edge 93 of the substrate 9 (release position) and a position P2 where it is relatively close to the peripheral edge 93 of the substrate 9 (regulating position). When the position regulating pin 13 is in the release position P1, the regulating surface 132d is sufficiently spaced away from the peripheral edge 93 of the substrate 9 in the normal position when viewed from above and from the side (dotted line in Figure 3 and upper panel of Figure 4). On the other hand, when the position regulating pin 13 is in the regulating position P2, the regulating surface 132d extends parallel to the tangent of the peripheral edge 93 of the substrate 9 in the normal position when viewed from above, and abuts against the peripheral edge 93 when viewed from the side (solid line in Figure 3 and lower panel of Figure 4). Specifically, the upper surface 1321 abuts against the peripheral edge 93 from diagonally above, the curved surface 1322 abuts against the peripheral edge 93 from the side, and the lower surface 1323 abuts against the peripheral edge 93 from diagonally below. With the position regulating pin 13 positioned at the regulating position P2, the regulating surface 132d may be biased against the peripheral edge 93 of the substrate 9.

[0045] Here, the multiple position regulating pins 13 provided on the base plate 11 are divided into two groups. Specifically, every other position regulating pin 13 along the circumferential direction of the reference circle C (that is, three position regulating pins 13 that are 120 degrees apart from each other when viewed from the rotation axis J1) are designated as the position regulating pins 13 belonging to the first group (hereinafter also referred to as "first position regulating pins 13a"), and the remaining three position regulating pins 13 belong to the second group (hereinafter also referred to as "second position regulating pins 13b").

[0046] When each first position regulating pin 13a is positioned at the regulating position P2 and each second position regulating pin 13b is positioned at the release position P1, a state is formed in which each first position regulating pin 13a regulates the position of the substrate 9 (first regulating state). When each second position regulating pin 13b is positioned at the regulating position P2 and each first position regulating pin 13a is positioned at the release position P1, a state is formed in which each second position regulating pin 13b regulates the position of the substrate 9 (second regulating state). In both the first and second regulating states, the substrate 9 is regulated to a predetermined position defined above the base plate 11 and is also regulated to prevent rotation relative to the base plate 11. That is, in the first or second regulating state, the regulating surfaces 132d of each first position regulating pin 13a or each second position regulating pin 13b contact each other at different positions along the circumferential direction on the peripheral edge 93 of the substrate 9. This restricts the position of the substrate 9 so that it does not displace from its predetermined position in the radial and vertical directions. Furthermore, the substrate 9 is restricted from rotational displacement around the rotation axis J1 relative to each position restricting pin 13 (and consequently the base plate 11) by the frictional force it receives from the restricting surface 132d that abuts (and is biased as necessary) against its peripheral edge 93 (i.e., it is restricted from relative rotation with respect to the base plate 11). Here, since the multiple position restricting pins 13 are provided on the circumference of a reference circle C centered on the rotation axis J1, the predetermined position where the substrate 9, which is restricted by each first position restricting pin 13a or each second position restricting pin 13b, is placed is the position where the center of the substrate 9 coincides with the rotation axis J1 (i.e., the normal position).

[0047] <3. Gas Discharge Section> <3-1. Structure> The gas discharge section 3 will be explained with reference to Figures 1, 2, and 5. Figure 5 is a side cross-sectional view of the base plate 11.

[0048] The gas discharge unit 3 comprises a first discharge structure 301, a second discharge structure 302, and a gas supply unit 303.

[0049] (1st discharge structure 301) The first discharge structure 301 is a structure for discharging gas from the upper surface 111 side of the base plate 11 and is provided on the base plate 11. Specifically, the first discharge structure 301 is composed of, for example, a hollow space 31 and a discharge passage 32.

[0050] Here, the base plate 11 comprises a main plate 51 and a center cover 52, with a hollow space 31 formed between them. Specifically, for example, the main plate 51 is a disc-shaped member, and a circular recess 51a is provided on its upper surface when viewed from above. On the other hand, the center cover 52 is a disc-shaped member with a smaller diameter than the main plate 51, and is provided to close the opening on the upper end side of the recess 51a. As an example, the center cover 52 is composed of a disc portion 52a and a peripheral wall portion 52b that protrudes downward along its periphery, and when the center cover 52 is provided to close the opening of the recess 51a, the disc portion 52a is spaced apart from the bottom surface of the recess 51a, and the outer peripheral wall of the peripheral wall portion 52b and the inner peripheral wall of the recess 51a are in airtight contact. In this state, the space provided between the main plate 51 and the center cover 52 (specifically, between the bottom surface of the recess 51a and the lower surface of the disc portion 52a) becomes the hollow space 31.

[0051] The discharge passage 32 extends within the base plate 11, from a first opening 32a provided in the base plate 11 to a second opening 32b that opens towards the upper surface 111 of the base plate 11. The discharge passage 32 is linear and connects the first opening 32a and the second opening 32b by a straight path. Here, for example, the discharge passage 32 penetrates the center cover 52 in the thickness direction, from a first opening 32a that opens towards the lower surface of the center cover 52 (for example, the root portion of the inner peripheral wall of the peripheral wall portion 52b) to a second opening 32b that opens towards the upper surface of the center cover 52. The first opening 32a that opens towards the lower surface of the center cover 52 faces the hollow space 31, and the second opening 32b that opens towards the upper surface of the center cover 52 faces the space on the upper surface 111 side of the base plate 11 (and thus the lower space U). In other words, the hollow space 31 and the lower space U are connected through the discharge passage 32.

[0052] Here, a plurality of discharge passages 32 are provided in the base plate 11. The plurality of discharge passages 32 are arranged along the circumferential direction of the base plate 11. Each first opening 32a of the plurality of discharge passages 32 is arranged at equal intervals along the circumference of a virtual circle (first virtual circle) C1 centered on the rotation axis J1, which is defined on the lower surface side of the center cover 52. Also, each second opening 32b of the plurality of discharge passages 32 is arranged at equal intervals along the circumference of a virtual circle (second virtual circle) C2 centered on the rotation axis J1, which is defined on the upper surface side of the center cover 52. However, it is preferable that the diameter of the second virtual circle C2 is smaller than the diameter of the reference circle C (i.e., the diameter of the substrate 9). In this case, the difference Δd1 between the radii of the reference circle C and the second virtual circle C2 is preferably 20 mm or less, and as an example, 16.5 mm. Also, it is preferable that the diameter of the second virtual circle C2 is larger than the diameter of the first virtual circle C1. The number of discharge passages 32 provided on the base plate 11 is preferably 100 or more and 200 or less, and as an example, 150.

[0053] (Second discharge structure 302) The second discharge structure 302, like the first discharge structure 301, is a structure for discharging gas from the upper surface 111 side of the base plate 11 and is provided on the base plate 11. Specifically, the second discharge structure 302 is composed of, for example, a central opening 33 and a discharge gap 34.

[0054] Here, an opening is provided in the center of the center cover 52, and a central ring 53 is provided in this opening. The central ring 53 is an annular member, and is positioned so that its center coincides with the axis of rotation J1. The opening provided in the central part of the central ring 53 forms the central opening 33.

[0055] On the upper surface of the central ring 53, a circular recess 53a is provided, as viewed from above, surrounding the central opening 33, and a disc 54 is supported therein. Specifically, the disc 54 is supported within the recess 53a by a support member (not shown), while maintaining a gap between itself and the recess 53a. The gap between the disc 54 and the recess 53a forms the discharge gap 34. Here, both the peripheral wall of the recess 53a and the peripheral wall of the disc 54, which is positioned opposite it, have a shape that widens as it extends upward (tapered shape). Therefore, the discharge gap 34 widens upward from the lower end opening 34a to the upper end opening 34b. However, the upper end opening 34b of the discharge gap 34 opens towards the upper surface 111 of the base plate 11 at a position closer to the rotation axis J1 than the second opening 32b of the discharge passage 32. In other words, the diameter of the opening 34b at the upper end of the discharge gap 34 is smaller than the diameter of the second virtual circle C2. For example, the diameter of the opening 34b at the upper end of the discharge gap 34 is 100 mm. The opening 34a at the lower end of the discharge gap 34 faces the central opening 33, and the opening 34b at the upper end of the discharge gap 34 faces the space on the upper surface 111 side of the base plate 11 (and thus the lower space U). In other words, the central opening 33 and the lower space U are in communication through the discharge gap 34.

[0056] (Gas supply unit 303) The gas supply unit 303 supplies gas to the first discharge structure 301 and the second discharge structure 302. The gas supply unit 303 includes, for example, a gas supply pipe 35 and a gas supply source 36.

[0057] The gas supply pipe 35 comprises a first supply pipe 351 that supplies gas to the first discharge structure 301 and a second supply pipe 352 that supplies gas to the second discharge structure 302. Here, the second supply pipe 352 is inserted inside the first supply pipe 351. In other words, the gas supply pipe 35 has a double structure.

[0058] The first supply pipe 351 is inserted through the inside of the shaft 141. Here, the shaft 141 is connected to the main body plate 51 by its upper end being supported by the main body boss 55. The main body boss 55 is attached to the lower surface of the main body plate 51 so as to surround an opening 51b provided in the center of the main body plate 51. The first supply pipe 351 is provided so that its upper end extends above the upper end of the shaft 141, and in this extended portion, it is supported by the main body boss 55 via a retaining cylinder 351a. In this state, the opening on the upper end side of the first supply pipe 351 is located in a recess 55a of the main body boss 55. The recess 55a communicates with the hollow space 31 via the opening 51b. Therefore, when gas is discharged from the opening on the upper end side of the first supply pipe 351, the gas is supplied to the hollow space 31 via the recess 55a and the opening 51b. The gas supplied to the hollow space 31 flows into each discharge passage 32 from each first opening 32a, flows through each discharge passage 32, and is discharged into the lower space U from each second opening 32b. In other words, the gas is discharged into the lower space U through the first discharge structure 301.

[0059] As described above, the second supply pipe 352 is inserted through the inside of the first supply pipe 351. The upper end portion of the second supply pipe 352 is provided to extend above the upper end of the first supply pipe 351, and in this extended portion, it is supported by the cover-side boss 56 via the retaining cylinder 352a. However, the cover-side boss 56 is attached to the lower surface of the central ring 53 so as to surround the central opening 33, and the upper end opening of the second supply pipe 352 is positioned in the central opening 33. Therefore, when gas is discharged from the upper end opening of the second supply pipe 352, the gas is supplied to the central opening 33. The gas supplied to the central opening 33 flows into the discharge gap 34 from the lower end opening 34a of the discharge gap 34, flows through the discharge gap 34, and is discharged into the lower space U from the upper end opening 34b. That is, gas is discharged into the lower space U through the second discharge structure 302.

[0060] In this configuration, a bearing 351b and a seal 351c are provided between the retaining cylinder 351a that holds the first supply pipe 351 and the main body boss 55, so that the first supply pipe 351 is airtightly attached to the main body boss 55 (and consequently the base plate 11) so that it can rotate freely around the axis of rotation J1. Similarly, a bearing 352b and a seal 352c are provided between the retaining cylinder 352a that holds the second supply pipe 352 and the cover boss 56, so that the second supply pipe 352 is airtightly attached to the cover boss 56 (and consequently the base plate 11) so that it can rotate freely around the axis of rotation J1. Therefore, even if the base plate 11 rotates, the first supply pipe 351 and the second supply pipe 352 do not rotate in response.

[0061] The gas supply source 36 is a source that supplies a predetermined gas to the gas supply pipe 35 (specifically, the first supply pipe 351 and the second supply pipe 352). The gas supplied from the gas supply source 36 may be, for example, an inert gas (nitrogen gas, argon gas, helium gas), low-humidity clean air, etc., but is not limited to these. The gas supplied from the gas supply source 36 may also be a high-pressure gas, compressed gas, etc.

[0062] The gas supply source 36 is connected to the gas supply pipe 35 via a pipe 363 in which a gas valve 361 and a flow rate adjustment unit 362 are inserted. However, the pipe 363 branches midway, with one branch section (first branch section) 363a connected to the first supply pipe 351 and the other branch section (second branch section) 363b connected to the second supply pipe 352. A flow rate ratio adjustment unit 364 is further inserted into the pipe 363, which adjusts the ratio (flow rate ratio) of the amount of gas flowing into the first branch section 363a and the amount of gas flowing into the second branch section 363b. Therefore, when the gas valve 361 is opened, gas is supplied to the first supply pipe 351 and the second supply pipe 352 at a predetermined flow rate ratio, and the gas is discharged from the openings at the upper ends of each supply pipe 351 and 352. The gas valve 361, flow rate adjustment unit 362, and flow rate ratio adjustment unit 364 operate in accordance with instructions from the control unit 4, and the gas discharge timing, discharge amount, flow rate ratio, etc., are controlled by the control unit 4.

[0063] <3-2. Direction of extension of the discharge path> The discharge passage 32 provided in the base plate 11 will be described with reference to Figures 6 to 9. Figures 6 to 8 are plan views showing examples of discharge passages 32 with different inclination angles θ1 (described later). Figure 9 is a side cross-sectional view of the base plate 11 near the discharge passage 32.

[0064] The discharge passage 32 satisfies the following first requirement. The first requirement is that the extension direction K of the discharge passage 32 is inclined downstream of the rotation direction R of the base plate 11 with respect to a virtual straight line D passing through the rotation axis J1 and the first opening 32a, when viewed from above. Here, the "extension direction K of the discharge passage 32" is the direction from the first opening 32a to the second opening 32b. Now, when viewed from above, with the virtual straight line D as the reference and the rotation direction R as positive, if we call the angle that the extension direction K of the discharge passage 32 makes with respect to the virtual straight line D the "angle of inclination θ1", then the first requirement is that the angle of inclination θ1 is greater than 0° and less than 180° (0° < θ1 < 180°). In other words, a discharge passage 32 that satisfies the first requirement has an angle of inclination θ1 that is greater than 0° and less than 180°. The discharge path 32A (0°<θ1≦45°) illustrated in Figure 6, the discharge path 32B (45°<θ1<90°) illustrated in Figure 7, and the discharge path 32C (90°≦θ1<180°) illustrated in Figure 8 all satisfy the first requirement.

[0065] It is preferable that the discharge passage 32 satisfies the following second requirement in addition to the first requirement. The second requirement is that the extending direction K of the discharge passage 32, when viewed from above, is inclined downstream of the rotation direction R of the base plate 11 with respect to the virtual straight line D, while moving away from the rotation axis J1. A discharge passage 32 that satisfies the second requirement in addition to the first requirement has an inclination angle θ1 that is greater than 0° and less than 90° (0° < θ1 < 90°). Discharge passage 32A (0° < θ1 ≤ 45°) illustrated in Figure 6 and discharge passage 32B (45° < θ1 < 90°) illustrated in Figure 7 both satisfy the second requirement in addition to the first requirement. However, the second requirement is not a mandatory requirement, and the discharge passage 32 does not have to satisfy the second requirement.

[0066] In addition to the first and second requirements, the discharge passage 32 preferably satisfies the following third requirement. The third requirement is that the angle between the extending direction K of the discharge passage 32 and the virtual straight line D is 45° or less when viewed from above. A discharge passage 32 that satisfies the third requirement in addition to the first and second requirements has an inclination angle θ1 that is greater than 0° and 45° or less (0° < θ1 ≤ 45°). The discharge passage 32A (0° < θ1 ≤ 45°) illustrated in Figure 6 satisfies the third requirement in addition to the first and second requirements. However, the third requirement is not a mandatory requirement, and the discharge passage 32 does not have to satisfy the third requirement.

[0067] In addition to the first requirement, the discharge passage 32 may also preferably satisfy the following fourth requirement. The fourth requirement is that the extension direction K of the discharge passage 32 is in a direction that is inclined upward while moving away from the axis of rotation J1. Now, if we take the horizontal plane H as the reference and vertical upward is considered positive, and call the angle that the extension direction K of the discharge passage 32 makes with respect to the horizontal plane H the "elevation angle θ2", then a discharge passage 32 that satisfies the fourth requirement in addition to the first requirement will have an inclination angle θ1 and an elevation angle θ2 that are both greater than 0° and less than 90° (0°<θ1<90°, 0°<θ2<90°). The discharge passage 32 illustrated in Figure 9 satisfies the fourth requirement in addition to the first requirement. However, the fourth requirement is not a mandatory requirement, and the discharge passage 32 does not have to satisfy the fourth requirement.

[0068] In addition to the first and fourth requirements, the discharge passage 32 may also preferably satisfy the following fifth requirement. The fifth requirement is that the angle between the extension direction K of the discharge passage 32 and the horizontal plane H is 45° or less. A discharge passage 32 that satisfies the fifth requirement in addition to the first and fourth requirements has an inclination angle θ1 that is greater than 0° and less than 90° (0° < θ1 < 90°), and an elevation angle θ2 that is greater than 0° and 45° or less (0° < θ2 ≤ 45°). The discharge passage 32 illustrated in Figure 9 satisfies the fifth requirement in addition to the first and fourth requirements. However, the fifth requirement is not a mandatory requirement, and the discharge passage 32 does not have to satisfy the fifth requirement.

[0069] <3-3. Gas Flow> The gas flow formed in the lower space U will be explained with reference to Figures 6 to 9, as well as Figure 10. Figure 10 is a diagram illustrating the gas flow formed in the lower space U.

[0070] (a) First discharge flow D1 When gas is supplied to the hollow space 31 by the gas supply unit 303, the gas flows from each first opening 32a into each discharge passage 32, is guided through each discharge passage 32 to each second opening 32b, and is discharged from each second opening 32b towards the upper surface 111 side of the base plate 11 (first discharge flow D1). The direction of gas discharge from each second opening 32b coincides with the extending direction K of the discharge passage 32. That is, gas is discharged from each second opening 32b along the extending direction K of the discharge passage 32.

[0071] Now, the velocity components obtained by decomposing the velocity vector V of the gas discharged from the second opening 32b into horizontal and vertical components are called the "horizontal velocity component Vh" and the "vertical velocity component Vd," respectively (Figure 9). In the case of a discharge passage 32 that satisfies the first requirement (0° < θ1 < 180°), the horizontal velocity component Vh of the velocity vector V of the gas discharged from the second opening 32b has a velocity component (first velocity component) V1 that is directed downstream in the rotation direction R along the tangential direction of the circle centered on the rotation axis J1 (Figures 6, 7, and 8). Here, when the substrate 9 rotates in the rotation direction R around the rotation axis J1, the gas on the lower surface 91 side of the substrate 9 is carried along with the lower surface 91 by friction with the lower surface 91, and as a result, an airflow (rotational airflow) Q that flows in the rotation direction R along the circumferential direction of the circle centered on the rotation axis J1 is formed in the lower space U. When the gas discharged from the second opening 32b has a first velocity component V1, the momentum (flow velocity) of the rotating airflow Q is not weakened by the gas discharged from the second opening 32b, but rather strengthened. Therefore, an airflow with sufficient velocity is formed in the lower space U. In the state where the substrate 9 is rotating and the processing liquid is supplied to its upper surface 92, the formation of an airflow with sufficient velocity in the lower space U prevents the processing liquid and its mist (processing liquid atmosphere) supplied to the upper surface 92 from flowing around to the lower surface 91.

[0072] Furthermore, in the case of a discharge passage 32 that satisfies both the first and second requirements (0° < θ1 < 90°), the horizontal velocity component Vh of the velocity vector V of the gas discharged from the second opening 32b has a velocity component (second velocity component) V2 that is directed outward along the radial direction of a circle centered on the rotation axis J1 (Figures 6 and 7). When the gas discharged from the second opening 32b has a second velocity component V2, an airflow with a velocity component directed outward along the radial direction of the substrate 9 is formed in the peripheral region Ue of the lower space U (the region outside the second virtual circle C2 when viewed from above). The formation of such an airflow can sufficiently suppress the radial inward movement of the processing liquid and its mist supplied to the upper surface 92 of the substrate 9 on the lower surface 91 side. Consequently, the amount of leakage of the processing liquid can be kept small.

[0073] Furthermore, in the case of a discharge passage 32 that satisfies the third requirement in addition to the first and second requirements (0° < θ1 ≤ 45°), the magnitude of the second velocity component V2 in the horizontal velocity component Vh of the velocity vector V of the gas discharged from the second opening 32b is greater than or equal to the magnitude of the first velocity component V1 (Figure 6). In other words, the gas discharged from the second opening 32b has a sufficiently large second velocity component V2. The larger the second velocity component V2 of the gas discharged from the second opening 32b, the larger the velocity component directed outward along the radial direction of the substrate 9 in the airflow formed in the peripheral region Ue of the lower space U becomes, and the width of the processing liquid leakage can be sufficiently kept small.

[0074] Furthermore, in the case of a discharge passage 32 that satisfies the fourth requirement in addition to the first requirement (0°<θ1<90°, 0°<θ2<90°), the velocity vector V of the gas discharged from the second opening 32b has a horizontal velocity component Vh having a first velocity component V1 and a second velocity component V2, and a vertical velocity component Vd that is vertically upward (Figure 9). In this case, an airflow is formed in the peripheral region Ue of the lower space U that is directed outward along the radial direction of the substrate 9 and slopes upward. By forming such an airflow, the processing liquid and its mist that would otherwise try to flow from the upper surface 92 to the lower surface 91 of the substrate 9 can be pushed back radially outward and upward of the substrate 9. This effectively suppresses the processing liquid and its mist from flowing onto the lower surface 91.

[0075] Furthermore, in the case of a discharge passage 32 that satisfies the fifth requirement in addition to the first and fourth requirements (0°<θ1<90, 0°<θ2≦45°), the magnitude of the horizontal velocity component Vh in the velocity vector V of the gas discharged from the second opening 32b is greater than or equal to the magnitude of the vertical velocity component Vd (Figure 9). In other words, the gas discharged from the second opening 32b has a sufficiently large horizontal velocity component Vh. The larger the horizontal velocity component Vh of the gas discharged from the second opening 32b, the larger the velocity component along the lower surface 91 of the substrate 9 in the airflow formed in the lower space U becomes, and an airflow with sufficient flow velocity is formed in the lower space U. This suppresses the processing liquid and its mist supplied to the upper surface 92 of the substrate 9 from flowing around to the lower surface 91.

[0076] (b) Second discharge flow D2 When gas is supplied to the central opening 33 by the gas supply unit 303, the gas flows into the discharge gap 34 from the lower end opening 34a, is guided through the discharge gap 34 to the upper end opening 34b, and is discharged from the upper end opening 34b toward the upper surface 111 of the base plate 11 (second discharge flow D2). Specifically, gas is discharged outward (radially) along the radial direction of the opening 34b from each position around the entire circumference of the upper end opening 34b. By forming such an airflow in the lower space U, the entire lower surface 91 of the substrate 9 can be protected by the gas.

[0077] <4. Processing Flow> The processing flow performed by the substrate processing apparatus 100 will be explained with reference to Figures 11 and 12. Figure 11 is a block diagram showing the configuration of the control unit 4. Figure 12 is a diagram showing the processing flow performed by the substrate processing apparatus 100.

[0078] The processing performed by the substrate processing apparatus 100 is carried out by the control unit 4 controlling each part of the substrate processing apparatus 100 (rotating mechanism 14, chemical valve 221a, flow rate adjustment unit 222a, rinse liquid valve 221b, flow rate adjustment unit 222b, gas valve 361, flow rate adjustment unit 362, flow rate ratio adjustment unit 364, pin drive mechanism 133, etc.). Furthermore, the series of processes described below are usually performed repeatedly. That is, once the series of processes for one substrate 9 is completed, the same series of processes is then performed on another new substrate 9.

[0079] In the substrate processing apparatus 100, a low flow rate (for example, 40 liters / minute) of gas is supplied from the gas supply source 36 to the gas supply pipe 35 even before the substrate 9 to be processed is brought into the substrate processing apparatus 100. The gas supplied to the gas supply pipe 35 is supplied to the first supply pipe 351 and the second supply pipe 352, respectively, at a predetermined flow rate ratio. The gas supplied to the hollow space 31 through the first supply pipe 351 flows into each discharge passage 32 from each first opening 32a, is guided through each discharge passage 32 to each second opening 32b, and is discharged from each second opening 32b to the upper surface 111 side of the base plate 11. In addition, the gas supplied to the central opening 33 through the second supply pipe 352 flows into the discharge gap 34 from the lower end opening 34a, is guided through the discharge gap 34 to the upper end opening 34b, and is discharged from the upper end opening 34b to the upper surface 111 side of the base plate 11. Even before the substrate 9 is brought in, a low flow rate of gas is discharged to the upper surface 111 of the base plate 11, thereby protecting the upper surface 111 of the base plate 11 and the support pins 12 and position regulating pins 13 provided thereon.

[0080] Step S1 With a low flow rate of gas being discharged to the upper surface 111 of the base plate 11, the substrate 9 to be processed is brought into the substrate processing apparatus 100. Specifically, first, an external transport mechanism inserts a hand holding the substrate 9 into the chamber of the substrate processing apparatus 100 and positions it above the base plate 11. Here, for example, a pattern of a device (a device in the process of being manufactured) is formed on one main surface of the substrate 9 to be processed, and the substrate processing apparatus 100 processes the other main surface on which the pattern is not formed. In this case, the substrate 9 held by the hand is oriented such that the main surface on which the pattern is formed faces downward (becoming the bottom surface 91), and the main surface on which the pattern is not formed faces upward (becoming the top surface 92).

[0081] Step S2 Next, the hand is lowered. When the hand holding the substrate 9 is positioned above the base plate 11, each support pin 12 is in the upper position, and each position regulating pin 13 is in the release position P1. Therefore, when the hand is lowered, the peripheral edge 93 of the substrate 9 is supported from below by each support pin 12. This transfers the substrate 9 from the hand onto each support pin 12. After that, the transport mechanism retracts the hand from above the base plate 11 and exits the chamber of the substrate processing device 100. When the hand is retracted from above the base plate 11, each support pin 12 is lowered and positioned in the lower position.

[0082] Step S3 Next, the pin drive mechanism 133 moves each position regulating pin 13 (at least one of each first position regulating pin 13a and each second position regulating pin 13b) from the release position P1 to the regulating position P2. When each position regulating pin 13 begins to move (rotate) toward the regulating position P2, first the lower surface 1323 of the regulating surface 132d comes into contact with the peripheral edge 93 of the substrate 9 supported by each support pin 12. Then, as each position regulating pin 13 continues to move, the substrate 9 is guided by the lower surface 1323 and moves upward (lifted) while maintaining a horizontal position, separating from each support pin 12. With each position regulating pin 13 in the regulating position P2 position, the substrate 9 is regulated to its normal position by each position regulating pin 13.

[0083] Step S4 Next, the flow rate of the gas supplied from the gas supply source 36 to the gas supply pipe 35 is switched from a low flow rate to a high flow rate (for example, 220 liters / minute). As described above, the gas supplied to the gas supply pipe 35 is supplied to the first supply pipe 351 and the second supply pipe 352, respectively, at a predetermined flow rate ratio. The gas supplied to the hollow space 31 through the first supply pipe 351 flows into each discharge passage 32 from each first opening 32a, is guided through each discharge passage 32 to each second opening 32b, and is discharged from each second opening 32b to the upper surface 111 side of the base plate 11. As a result, the first discharge flow D1 is formed in the lower space U. Furthermore, the gas supplied to the central opening 33 through the second supply pipe 352 flows into the discharge gap 34 from the lower end opening 34a, is guided through the discharge gap 34 to the upper end opening 34b, and is discharged from the upper end opening 34b toward the upper surface 111 of the base plate 11. This forms a second discharge flow D2 in the lower space U. However, it is preferable that the flow rate L2 of the gas supplied to the second supply pipe 352 (and consequently, the flow rate of the gas discharged from the upper end opening 34b of the discharge gap 34) is smaller than the flow rate L1 of the gas supplied to the first supply pipe 351 (and consequently, the total flow rate of the gas flowing in from each first opening 32a of the multiple discharge passages 32 and discharged from each second opening 32b). As an example, the ratio of the flow rate L1 of the gas supplied to the first supply pipe 351 to the flow rate L2 of the gas supplied to the second supply pipe 352 is 9 to 1 (L1:L2=9:1).

[0084] Step S5 Next, the base plate 11 starts rotating. That is, the rotation mechanism 14 rotates the base plate 11 around the rotation axis J1, increasing its rotational speed to a predetermined liquid processing rotational speed. The substrate 9 is restricted from rotating relative to the base plate 11 by the position regulating pins 13, so it rotates together with the base plate 11 (at the same rotational speed). Therefore, when the base plate 11 starts rotating and its rotational speed increases to the liquid processing rotational speed, the substrate 9 also starts rotating together with the base plate 11 and its rotational speed increases to the liquid processing rotational speed. The liquid processing rotational speed is, for example, 300 to 1500 rpm.

[0085] Step S6 When the rotational speed of the base plate 11 reaches the liquid processing rotational speed, the rotation mechanism 14 maintains the rotational speed of the base plate 11 at the liquid processing rotational speed. While the rotational speed of the base plate 11 is maintained at the liquid processing rotational speed, the rotational speed of the substrate 9, which rotates together with the base plate 11, is also maintained at the liquid processing rotational speed. In this state, the processing liquid supply unit 2 starts supplying the chemical solution as the first processing liquid. Specifically, the processing liquid nozzle 21 is positioned at the discharge position, and the chemical solution valve 221a is opened. Then, the chemical solution supplied from the chemical solution supply source 22a starts to be discharged from the processing liquid nozzle 21, and the chemical solution starts to be supplied to the upper surface 92 of the substrate 9. The chemical solution supplied to the upper surface 92 of the substrate 9 spreads toward the periphery due to the centrifugal force caused by the rotation of the substrate 9, and the entire upper surface 92 is treated with the chemical solution. In other words, chemical treatment is performed on the substrate 9.

[0086] During the chemical treatment, a first discharge flow D1 is formed in the lower space U, and the force of the rotating airflow Q is increased by the first discharge flow D1, so that an airflow with sufficient velocity is formed in the lower space U. Therefore, the chemical solution and its mist supplied to the upper surface 92 of the substrate 9 are prevented from flowing back to the lower surface 91. In addition, during the chemical treatment, a second discharge flow D2 is formed in the lower space U, so that the entire lower surface 91 of the substrate 9 is protected by the gas.

[0087] Step S7 Next, if necessary, the pin drive mechanism 133 alternately positions the first position regulating pin 13a and the second position regulating pin 13b at the regulating position P2, thereby alternately forming the first regulating state and the second regulating state. There is a risk that the chemical solution may not be sufficiently supplied to the positions where the position regulating pins 13 face each other (pin opposing positions) on the peripheral edge 93 of the substrate 9. However, since the position regulating pins 13 that regulate the position of the substrate 9 are different in the first regulating state and the second regulating state, the pin opposing positions will also be different. Therefore, in one regulating state, the chemical solution is supplied to the locations that were pin opposing positions in the other regulating state. In other words, by alternately forming the first regulating state and the second regulating state while the chemical solution treatment is being performed, the chemical solution is sufficiently supplied to the entire peripheral edge 93 of the substrate 9, and the chemical solution treatment proceeds uniformly across the entire peripheral edge 93. Note that the first regulating state and the second regulating state may also be alternately formed during the subsequent rinsing treatment.

[0088] Step S8 After a predetermined time has elapsed since the supply of the first treatment solution (chemical solution) began, the treatment solution supply unit 2 stops supplying the chemical solution and starts supplying the second treatment solution (rinsing solution). Specifically, with the treatment solution nozzle 21 positioned at the discharge location, the chemical solution valve 221a is closed and the rinsing solution valve 221b is opened. Then, instead of the chemical solution supplied from the chemical solution supply source 22a, the rinsing solution supplied from the rinsing solution supply source 22b is discharged from the treatment solution nozzle 21, and the rinsing solution is supplied to the upper surface 92 of the substrate 9. The rinsing solution supplied to the upper surface 92 of the substrate 9 spreads toward the periphery due to the centrifugal force caused by the rotation of the substrate 9. As a result, the chemical solution on the upper surface 92 of the substrate 9 is replaced by the rinsing solution and washed away (rinsed). In other words, the substrate 9 is rinsed.

[0089] Even while the rinsing process is being performed, a first discharge flow D1 is formed in the lower space U, and the force of the rotating airflow Q is increased by the first discharge flow D1, so that an airflow with sufficient velocity is formed in the lower space U. Therefore, the rinsing liquid supplied to the upper surface 92 of the substrate 9 (for example, the rinsing liquid supplied to the upper surface 92 of the substrate 9 and mixed with the chemical solution adhering thereto) and its mist are prevented from flowing around to the lower surface 91. In addition, even while the rinsing process is being performed, a second discharge flow D2 is formed in the lower space U, so that the entire lower surface 91 of the substrate 9 is protected by gas.

[0090] Step S9 After a predetermined time has elapsed since the start of supplying the rinse liquid as the second processing liquid, the processing liquid supply unit 2 stops supplying the rinse liquid. Specifically, the rinse liquid valve 221b is closed. As a result, the discharge of rinse liquid from the processing liquid nozzle 21 stops.

[0091] Step S10 Next, the rotating mechanism 14 increases the rotational speed of the base plate 11 to a drying rotational speed that is sufficiently greater than the liquid processing rotational speed. When the rotational speed of the base plate 11 is increased to the drying rotational speed, the rotational speed of the substrate 9, which rotates together with the base plate 11, also increases to the drying rotational speed. The drying rotational speed is, for example, 1000 to 2000 rpm.

[0092] Step S11 When the rotational speed of the base plate 11 reaches the drying rotational speed, the rotation mechanism 14 maintains the rotational speed of the base plate 11 at the drying rotational speed. While the rotational speed of the base plate 11 is maintained at the drying rotational speed, the rotational speed of the substrate 9, which rotates together with the base plate 11, is also maintained at the drying rotational speed. In this state, a large centrifugal force acts on the liquid adhering to the substrate 9, causing the liquid to be spun around the substrate 9, and the substrate 9 is dried (spin-drying process). During the spin-drying process, the first restricted state and the second restricted state may be formed alternately.

[0093] Step S12 Once the liquid adhering to the substrate 9 has been sufficiently shaken off, the rotation of the base plate 11 stops. That is, the rotation mechanism 14 reduces the rotation speed of the base plate 11 from the drying rotation speed to zero. When the rotation speed of the base plate 11 is reduced from the drying rotation speed to zero, the rotation speed of the substrate 9, which rotates together with the base plate 11, also decreases from the drying rotation speed to zero.

[0094] Step S13 Next, the flow rate of the gas supplied from the gas supply source 36 to the gas supply pipe 35 is switched from a high flow rate to a low flow rate.

[0095] Step S14 Next, the pin drive mechanism 133 moves each position regulating pin 13 from the regulating position P2 to the release position P1. As each position regulating pin 13 moves, the substrate 9 moves downward while maintaining a horizontal position, guided by the lower surface 1323 of the regulating surface 132d. When each position regulating pin 13 is in the release position P1, the substrate 9 is supported from below by each support pin 12. Subsequently, each support pin 12 is raised and positioned in the upper position.

[0096] Step S15 Subsequently, the substrate 9 is discharged from the substrate processing device 100. Specifically, an external transport mechanism inserts a hand into the chamber of the substrate processing device 100, moves it between the lower surface 91 of the substrate 9, which is supported by each support pin 12, and the base plate 11, and then raises it. This transfers the substrate 9 from each support pin 12 onto the hand. After that, the transport mechanism removes the hand holding the substrate 9 from the chamber of the substrate processing device 100.

[0097] <5.Flow velocity distribution> Figure 13 shows the velocity distribution of the gas flow in the peripheral region Ue of the lower space U when the substrate 9 is rotating, obtained from a CFD (Computational Fluid Dynamics) simulation. However, Figure 13 shows the gas velocity distribution in multiple horizontal planes with different distances from the lower surface 91 of the substrate 9 (i.e., different height positions in the lower space U). For clarity, the periphery of the substrate 9 (dotted line) and the position regulating pins 13 (solid line) are superimposed on the velocity distribution in Figure 13.

[0098] In the "Example," the base plate 11 is provided with multiple discharge passages 32, and their extending direction K is inclined downstream of the rotation direction R with respect to a virtual straight line D when viewed from above, and the angle between the extending direction K and the virtual straight line D is 28° (θ1=28°) (Figure 6). In "Comparative Example 1," the base plate 11 is not provided with discharge passages 32. In "Comparative Example 2," the base plate 11 is provided with multiple discharge passages 81, and their extending direction K is not inclined with respect to the virtual straight line D when viewed from above (θ1=0°) (Figure 15(a)). In "Comparative Example 3," the rotation direction R of the base plate 11 (and thus the substrate 9) is the opposite direction to that of the "Example." In other words, in "Comparative Example 3," the base plate 11 is provided with multiple discharge passages 82, and when viewed from above, their extending direction K is inclined upstream of the rotational direction R with respect to the virtual straight line D, and the angle between the extending direction K and the virtual straight line D is 28° (θ1 = -28°) (Figure 15(b)).

[0099] In Comparative Example 1, the flow velocity in the peripheral region Ue is relatively small, and the flow velocity is particularly small near the position regulating pin 13. In contrast, in the embodiment, the flow velocity in the peripheral region Ue is sufficiently large throughout the entire circumferential direction, and there is no localized decrease in flow velocity near the position regulating pin 13. This is thought to be because, in the embodiment, the force (flow velocity) of the rotating airflow Q is strengthened by the gas discharged from the second opening 32b, thereby forming an airflow with sufficient velocity in the lower space U.

[0100] In Comparative Example 2, areas with high and low flow velocities alternate along the circumferential direction in the peripheral region Ue. In contrast, in the Example, the flow velocity in the peripheral region Ue is sufficiently high throughout the entire circumferential direction, and no areas with locally low flow velocities appear (the flow velocity is uniform). The reason for this is thought to be as follows: In Comparative Example 2, the extending direction K of the discharge passage 81 is not inclined with respect to the virtual straight line D when viewed from above (it follows the virtual straight line D). Therefore, the horizontal velocity component Vh of the velocity vector V of the gas discharged from the second opening 81b has only a second velocity component V2 that points outward along the radial direction of a circle centered on the rotation axis J1, and does not have a first velocity component V1 that points downstream in the rotation direction R along the tangential direction of the circle (Vh=V2). Therefore, the gas discharged from each second opening 81b flows independently outward along the radial direction of the substrate 9, and a region with locally low flow velocity appears in the gaps between them (i.e., the gaps between adjacent first discharge flows D1). On the other hand, in the embodiment, the extending direction K of the discharge passage 32 is inclined downstream of the rotation direction R with respect to the virtual straight line D when viewed from above, so the gas discharged from the second opening 32b has not only a second velocity component V2 but also a first velocity component V1. Therefore, the momentum of the rotating airflow Q is strengthened by the gas discharged from the second opening 32b, and an airflow with sufficient flow velocity is formed in the gaps between the gases discharged from each second opening 32b.

[0101] In Comparative Example 3, the flow velocity in the peripheral region Ue is smaller than in the Example throughout the entire circumferential direction. The reason for this is thought to be as follows: In Comparative Example 3, the extending direction K of the discharge passage 82 is inclined upstream of the rotation direction R with respect to the virtual straight line D when viewed from above. Therefore, the horizontal velocity component Vh of the velocity vector V of the gas discharged from the second opening 82b has a velocity component V1' that is directed upstream of the rotation direction R along the tangential direction of the circle centered on the rotation axis J1. Consequently, the gas discharged from the second opening 82b collides with the rotating airflow Q, and the momentum of both is weakened (cancels out). As a result, the flow velocity in the peripheral region Ue is small throughout the entire circumferential direction. On the other hand, in the embodiment, the extending direction K of the discharge passage 32 is inclined downstream of the rotation direction R with respect to the virtual straight line D when viewed from above. Therefore, the horizontal velocity component Vh of the velocity vector V of the gas discharged from the second opening 32b has a first velocity component V1 that is directed downstream of the rotation direction R along the tangential direction of the circle centered on the rotation axis J1. Consequently, the momentum of the rotating airflow Q is strengthened by the gas discharged from the second opening 32b. As a result, the flow velocity in the peripheral region Ue becomes large throughout the circumferential direction.

[0102] <6. Effects> The substrate processing apparatus 100 according to the above embodiment includes a base plate 11, a plurality of position regulating pins 13 provided on the base plate 11 for regulating the position of a substrate 9 arranged horizontally above the base plate 11, a rotation mechanism 14 for rotating the base plate 11 around a vertically extending rotation axis J1, a processing liquid supply unit 2 for supplying processing liquid to the upper surface 92 of the substrate 9, a discharge passage 32 extending within the base plate from a first opening 32a provided on the base plate 11 to a second opening 32b opening toward the upper surface 111 of the base plate 11, and a gas supply unit 303 for introducing gas into the first opening 32a and discharging it from the second opening 32b. Here, the direction K of the discharge passage 32 extending from the first opening 32a to the second opening 32b is, when viewed from above, inclined downstream of the rotation direction R of the base plate 11 with respect to a virtual straight line D passing through the rotation axis J1 and the first opening 32a (first requirement).

[0103] When the discharge passage 32 satisfies the first requirement, the horizontal velocity component Vh of the velocity vector V of the gas discharged from the second opening 32b, which opens to the upper surface 111 side of the base plate 11, has a first velocity component V1 that is directed downstream in the rotation direction R along the tangential direction of the circle centered on the rotation axis J1. A rotating airflow Q is formed on the lower surface 91 side of the rotating substrate 9, flowing in the rotation direction R along the circumferential direction of the circle centered on the rotation axis J1. Because the gas discharged from the second opening 32b has the first velocity component V1, the momentum (flow velocity) of the rotating airflow Q is not weakened by the discharged gas, but rather strengthened. Therefore, an airflow with sufficient flow velocity is formed in the lower space U. This prevents the processing liquid supplied to the upper surface 92 of the substrate 9 from flowing back to the lower surface 91 of the substrate 9.

[0104] If the discharge passage 32 satisfies the second requirement in addition to the first requirement (i.e., the extension direction K of the discharge passage 32 is, when viewed from above, inclined downstream of the rotation direction R of the base plate 11 with respect to a virtual straight line D, while moving away from the rotation axis J1), then the horizontal velocity component Vh of the velocity vector V of the gas discharged from the second opening 32b will have a velocity component (second velocity component) V2 that points outward along the radial direction of a circle centered on the rotation axis J1. Therefore, the radial inward movement of the processing liquid on the lower surface 91 side of the substrate 9 can be sufficiently suppressed. Consequently, the amount of leakage of the processing liquid can be kept small.

[0105] If the discharge passage 32 satisfies the third requirement in addition to the first and second requirements (i.e., the angle between the extending direction K of the discharge passage 32 and the virtual straight line D is 45° or less when viewed from above), then the gas discharged from the second opening 32b will have a sufficiently large second velocity component V2. Therefore, the amount of leakage of the processed liquid can be kept sufficiently small.

[0106] If the discharge passage 32 satisfies the fourth requirement in addition to the first requirement (i.e., the extension direction K of the discharge passage 32 is in a direction that is inclined upward while moving away from the rotation axis J1), then the velocity vector V of the gas discharged from the second opening 32b will have a horizontal velocity component Vh having a first velocity component V1 and a second velocity component V2, and a vertical velocity component Vd pointing vertically upward. Therefore, the processing liquid that would otherwise try to flow from the upper surface 92 of the substrate 9 to the lower surface 91 of the substrate 9 can be pushed back radially outward and upward of the substrate 9. This effectively prevents the processing liquid from flowing onto the lower surface 91 of the substrate 9.

[0107] If the discharge passage 32 satisfies the fifth requirement in addition to the first and fourth requirements (i.e., the angle between the extension direction K of the discharge passage 32 and the horizontal plane H is 45° or less), the gas discharged from the second opening 32b will have a sufficiently large horizontal velocity component Vh. Therefore, an airflow with sufficient velocity is formed in the lower space U, and the processing liquid is prevented from flowing back onto the lower surface 91 of the substrate 9.

[0108] Furthermore, in the above embodiment, a plurality of discharge passages 32 are provided in the base plate 11, and the first opening 32a of each of the plurality of discharge passages 32 is arranged on the circumference of a first virtual circle C1 centered on the rotation axis J1, and the second opening 32b of each of the plurality of discharge passages 32 is arranged on the circumference of a second virtual circle C2, which has a larger diameter than the first virtual circle C1 and is centered on the rotation axis J1. With this configuration, an airflow with sufficient velocity is formed over the entire circumferential direction in the region outside the second virtual circle C2 when viewed from above in the lower space U (the peripheral region Ue of the lower space U). As a result, leakage of the processing liquid over the entire circumferential direction of the substrate 9 is sufficiently suppressed.

[0109] Furthermore, in the above embodiment, a third opening (an opening at the upper end of the discharge gap 34) 34b is provided, which opens on the upper surface side of the base plate 11 at a position closer to the rotation axis J1 than the second opening 32b. The gas supply unit 303 supplies gas at a flow rate smaller than the total flow rate of gas flowing into each of the first openings 32a of the plurality of discharge passages 32 to the third opening 34b, causing it to be discharged from the third opening 34b. With this configuration, the leakage of the processing liquid can be sufficiently suppressed over the entire circumferential direction of the substrate 9, and the lower surface 91 of the substrate 9 can be protected by the gas.

[0110] Furthermore, the substrate processing method according to the above embodiment includes a position regulating step (step S3) in which a substrate 9, which is positioned horizontally above the base plate 11, is regulated by a position regulating pin 13 provided on the base plate 11; a discharge step (step S4) in which gas flowing in from a first opening 32a provided on the base plate 11 is guided through a discharge passage 32 to a second opening 32b and discharged from the second opening 32b to the upper surface 111 side of the base plate 11; a rotation step (step S5) in which the base plate 11 is rotated around a rotation axis J1 extending vertically; and a processing liquid supply step (step S6) in which processing liquid is supplied to the upper surface 92 of the substrate 9. Here, the extending direction K of the discharge passage 32 from the first opening 32a to the second opening 32b is, when viewed from above, inclined downstream of the rotation direction R of the base plate 11 with respect to a virtual straight line D passing through the rotation axis J1 and the first opening 32a. This configuration makes it possible to prevent the processing liquid supplied to the upper surface 92 of the substrate 9 from flowing onto the lower surface 91 of the substrate 9.

[0111] <7. Variation> The configuration and operation of the substrate processing apparatus 100 according to the above embodiment can be modified as appropriate. In the following description, elements similar to those described in the above embodiment will be denoted by the same reference numerals, and their descriptions will be omitted.

[0112] In the above embodiment, it is also preferable that the discharge passage 32 satisfies the following sixth requirement in addition to the first and fourth requirements. The sixth requirement is that the angle (elevation angle) θ2 between the extending direction K of the discharge passage 32 and the horizontal plane H is defined so that the gas discharged from the second opening 32b reaches the peripheral region E of the substrate 9, which is positioned above the base plate 11 and its position is restricted by the position regulating pin 13 (Figure 9). However, the "peripheral region E of the substrate 9" referred to here is an annular region 20 mm from the end face of the substrate 9. When the elevation angle θ2 is defined so that the gas discharged from the second opening 32b reaches the peripheral region E of the substrate 9, an airflow with sufficient velocity is formed near the peripheral region E, and the processing liquid that tries to flow from the upper surface 92 to the lower surface 91 of the substrate 9 can be effectively pushed back radially outward and upward of the substrate 9. This effectively suppresses the processing liquid from flowing to the lower surface 91 of the substrate 9. In order to particularly effectively suppress the processing liquid from flowing onto the lower surface 91 of the substrate 9, it is preferable that the elevation angle θ2 be defined such that the gas discharged from the second opening 32b reaches a position sufficiently close to the end face of the substrate 9 within the peripheral region E. The range of elevation angles θ2 that allows the gas discharged from the second opening 32b to reach the peripheral region E of the substrate 9 is determined by the positional relationship between the second opening 32b and the peripheral edge 93 of the substrate 9. For example, the greater the distance between the second opening 32b and the peripheral edge 93 of the substrate 9 when viewed from above (i.e., the greater the difference in radius d1 between the second virtual circle C2 and the reference circle C), the smaller the elevation angle θ2 that allows the gas to reach the peripheral region E of the substrate 9. For example, if the radius difference d1 is 16.5 mm and the distance between the lower surface 91 of the substrate 9 and the upper surface 111 of the base plate 11 is 4.5 mm, setting the elevation angle θ2 to 15° allows the gas discharged from the second opening 32b to reach a position sufficiently close to the edge face of the substrate 9.

[0113] In the above embodiment, the closer the inclination angle θ1 is to 0° within the range greater than 0°, the larger the magnitude of the second velocity component V2 in the horizontal velocity component Vh of the velocity vector V of the gas discharged from the second opening 32b becomes compared to the first velocity component V1. In view of this, it is preferable that the inclination angle θ1 is greater than 0° and 30° or less. As an example, it is preferable that the inclination angle θ1 is 28°.

[0114] In the above embodiment, the closer the elevation angle θ2 is to 0° in the range greater than 0°, the larger the magnitude of the horizontal velocity component Vh becomes in the velocity vector V of the gas discharged from the second opening 32b compared to the vertical velocity component Vd. In view of this, the elevation angle θ2 is preferably 30° or less, and particularly preferably 15° or less.

[0115] In the above embodiment, the cross-section of the discharge passage 32 may be circular, for example. In that case, the diameter of the discharge passage 32 may be, for example, 1 mm or less (0.9 mm as an example). The flow velocity of the gas discharged from the second opening 32b increases as the cross-sectional area of ​​the discharge passage 32 (the area of ​​the cross-section perpendicular to the direction of extension) decreases. By setting the diameter of the discharge passage 32 to 1 mm or less, the flow velocity of the gas discharged from the second opening 32b can be made sufficiently large.

[0116] In the above embodiment, the gas supply source 36 and the gas supply pipes 35 (first supply pipe 351 and second supply pipe 352) were connected via a branched pipe 363. However, the pipe connecting the gas supply source 36 and the first supply pipe 351 and the pipe connecting the gas supply source 36 and the second supply pipe 352 may be provided independently, with a gas valve and a flow rate adjustment unit interposed in each pipe. With this configuration, the timing of gas supply to the first supply pipe 351 and the second supply pipe 352, etc., can be defined independently of each other.

[0117] The configuration of the gas discharge unit 3 according to the above embodiment can be modified as appropriate. Figure 14 shows the configuration of a modified gas discharge unit 7. As described above, in Figure 14 and the following description, elements similar to those described in the above embodiment are denoted by the same reference numerals, and their descriptions are omitted.

[0118] In this modified version, the center cover 52 is composed of a disc portion 52a, a peripheral wall portion 52b projecting downward along its periphery, and a projection portion 52c projecting downward from the central part of the disc portion 52a. The projection portion 52c engages with the main plate 51 and is connected to the shaft 141. A recess 71 with an open lower end is provided in the center of the projection portion 52c. The opening at the lower end of the recess 71 communicates with the inside of the shaft 141. The projection portion 52c is also provided with a first communication passage 72 that connects the inside of the recess 71 to the hollow space 31. In other words, the inside of the recess 71 and the hollow space 31 communicate through the first communication passage 72. The first communication passage 72 is, for example, a through passage extending radially along the projection portion 52c, and multiple such passages are arranged along the circumferential direction of the projection portion 52c. In this modification, a second connecting passage 73 is provided in the center of the disc portion 52a, penetrating the disc portion 52a in the thickness direction. The opening 73a at the lower end of the second connecting passage 73 communicates with the interior of the recess 71, and the opening 73b at the upper end of the second connecting passage 73 faces the space on the upper surface 111 side of the base plate 11 (and thus the lower space U). In other words, the recess 71 and the lower space U communicate through the second connecting passage 73. In this modification, the opening 73b at the upper end of the second connecting passage 73 forms a third opening (i.e., a third opening that opens to the upper surface side of the base plate 11 at a position closer to the axis of rotation J1 than the second opening 32b).

[0119] A gas supply pipe 74 is inserted inside the shaft 141. The upper end of the gas supply pipe 74 is provided to extend above the upper end of the shaft 141, and this extended portion is positioned within the recess 71. The upper end surface 74a of the gas supply pipe 74 is tapered. That is, the upper end surface 74a of the gas supply pipe 74 widens so as to slope upward as it extends radially outward. The gas supply pipe 74 is connected to the gas supply source 36 via a pipe 363 in which a gas valve 361 and a flow rate adjustment section 362 are interposed (see Figure 1). Note that the gas supply pipe 74 is a single-walled structure and not a double-walled structure, so the pipe 363 does not branch in this modified example.

[0120] In this configuration, when the gas valve 361 is opened, gas is supplied from the gas supply source 36 to the gas supply pipe 74, and the gas is discharged from the opening at the upper end of the gas supply pipe 74. This supplies gas into the recess 71. A portion of the gas supplied into the recess 71 is supplied to the hollow space 31 through each first connecting passage 72. As described in the above embodiment, the gas supplied to the hollow space 31 flows from each first opening 32a into each discharge passage 32, flows through each discharge passage 32, and is discharged from each second opening 32b into the lower space U. On the other hand, the remaining gas supplied into the recess 71 flows from the opening 73a at the lower end of the second connecting passage 73 into the second connecting passage 73, flows through the second connecting passage 73, and is discharged from the opening 73b at its upper end into the lower space U.

[0121] In this modified example, the flow rate ratio between the total flow rate of gas flowing into each of the first openings 32a of the multiple discharge passages 32 and the flow rate of gas supplied to the opening 73b of the second communication passage 73 is determined according to the ratio of the sum of the cross-sectional areas of the multiple first communication passages 72 to the cross-sectional area of ​​the second communication passage 73 (flow path area ratio), the taper angle of the upper end surface 74a of the gas supply pipe 74 (angle of opening relative to the rotation axis J1), and so on. In other words, the flow rate ratio can be set to the desired value by appropriately defining the flow path area ratio, taper angle, etc. For example, all other conditions being equal, the smaller the cross-sectional area of ​​the second communication passage 73, the smaller the ratio of the gas flow rate supplied to the opening 73b of the second communication passage 73, and the larger the ratio of the total flow rate of gas flowing into each of the multiple discharge passages 32. For example, all other things being equal, as the taper angle increases, the ratio of the gas flow rate supplied to the opening 73b of the second communication passage 73 decreases, and the ratio of the total gas flow rate into each of the first openings 32a of the multiple discharge passages 32 increases. Similar to the embodiment described above, in this modified example, it is preferable to supply gas at a flow rate smaller than the total gas flow rate into each of the first openings 32a of the multiple discharge passages 32 to the opening 73b (third opening) of the second communication passage 73 and discharge it from there. In other words, it is preferable that the flow path area ratio, taper angle, etc. are defined such that the flow rate of gas discharged from the opening 73b of the second communication passage 73 is smaller than the total gas flow rate discharged from each of the second openings 32b of the multiple discharge passages 32. As an example, the flow path area ratio, taper angle, etc. may be defined such that the flow rate ratio of the total gas flow rate discharged from each of the second openings 32b of the multiple discharge passages 32 to the flow rate of gas discharged from the opening 73b of the second communication passage 73 is 9:1.

[0122] In the above embodiment, the upper surface 111 of the base plate 11 is provided with an annular stepped portion 114 (Figures 2 and 5) extending along the circumference of a circle centered on the rotation axis J1, on the side of the rotation axis J1 that is inward from the periphery of the substrate 9 which is positioned horizontally above it, so that the side of the rotation axis J1 is relatively lower. When such a stepped portion 114 is provided, the distance between the upper surface 111 of the base plate 11 and the lower surface 91 of the substrate 9 becomes relatively larger on the inside of the stepped portion 114 and relatively smaller on the outside of the stepped portion 114. Therefore, when gas is discharged into the lower space U, the velocity of the gas flowing out through the gap between the periphery 93 of the substrate 9 and the upper surface 111 of the base plate 11 is sufficiently increased. As a result, when processing with a processing liquid is performed, the processing liquid and its mist supplied to the upper surface 92 of the substrate 9 are prevented from flowing around to the lower surface 91. The stepped portion 114 can be annular in shape, following the circumference of a circle centered on the axis of rotation J1 when viewed from above, but it does not need to be a perfect annular shape. For example, if various members (e.g., support pins 12, position regulating pins 13, etc.) are provided on the circumference, the stepped portion 114 can be provided so as to avoid those members and detour around them towards the axis of rotation J1.

[0123] In the above embodiment, the chemical solution as the first processing liquid and the rinsing liquid as the second processing liquid do not necessarily have to be discharged from the same processing liquid nozzle 21, and a chemical solution nozzle for discharging the chemical solution and a rinsing liquid nozzle for discharging the rinsing liquid may be provided separately.

[0124] The processing performed by the substrate processing apparatus 100 according to the above embodiment may be, for example, a cleaning process to remove contaminants, particles, oxide films, etc., adhering to the main surface of the substrate 9, or it may be an etching process. The substrate 9 to be processed by the substrate processing apparatus 100 may be a semiconductor substrate, a photomask glass substrate, a liquid crystal display glass substrate, a plasma display glass substrate, a FED (Field Emission Display) substrate, an optical disc substrate, a magnetic disc substrate, a magneto-optical disc substrate, etc. The shape of the substrate 9 to be processed may be a disc or other shape (for example, a rectangular plate).

[0125] As described above, the substrate processing apparatus and substrate processing method have been described in detail, but the above description is illustrative in all respects and does not limit the substrate processing apparatus and substrate processing method. It is understood that countless variations not illustrated can be envisioned without falling outside the scope of this disclosure. The components described in each of the above embodiments and each of the above variations can be combined or omitted as appropriate, as long as they do not contradict each other. [Explanation of Symbols]

[0126] 100 Substrate Processing Equipment 1. Spin Chuck 11 Base Plate 12 support pins 13 Position regulating pins 14 Rotation mechanism 2. Processing liquid supply unit 3. Gas Supply Department 301 1st discharge structure 302 Second discharge structure 303 Gas Supply Department 31 Hollow space 32 Discharge path 32a 1st opening 32b 2nd opening 33 Central opening 34 Discharge gap 35 Gas supply pipe 351 1st supply pipe 352 2nd supply pipe 36 Gas supply sources K Discharge path extension direction θ1 Tilt angle θ2 Elevation angle R rotation direction

Claims

1. base plate and A plurality of position-regulating pins are provided on the base plate and are used to regulate the position of a substrate that is positioned horizontally above the base plate, A rotation mechanism that rotates the base plate around a rotation axis extending vertically, A processing liquid supply unit that supplies processing liquid to the upper surface of the substrate, A discharge passage extends within the base plate from a first opening provided in the base plate to a second opening that opens on the upper surface side of the base plate, A gas supply unit that flows gas into the first opening and discharges it from the second opening, Equipped with, The direction in which the discharge passage extends from the first opening to the second opening is, when viewed from above, inclined downstream of the rotational direction of the base plate with respect to a virtual straight line passing through the rotation axis and the first opening. Circuit board processing equipment.

2. A substrate processing apparatus according to claim 1, The aforementioned extending direction, when viewed from above, is a direction that moves away from the axis of rotation and is inclined downstream of the rotational direction of the base plate with respect to the virtual straight line. Circuit board processing equipment.

3. A substrate processing apparatus according to claim 2, When viewed from above, the angle between the extension direction and the virtual straight line is 45° or less. Circuit board processing equipment.

4. A substrate processing apparatus according to any one of claims 1 to 3, The aforementioned extending direction is a direction that moves away from the rotation axis and inclins upward. Circuit board processing equipment.

5. A substrate processing apparatus according to claim 4, The angle between the extension direction and the horizontal plane is 45° or less. Circuit board processing equipment.

6. A substrate processing apparatus according to claim 4, The angle between the extending direction and the horizontal plane is defined such that the gas discharged from the second opening reaches the peripheral region of the substrate, which is positioned above the base plate and whose position is restricted by the position-restricting pin. Circuit board processing equipment.

7. A substrate processing apparatus according to any one of claims 1 to 3, Multiple discharge passages are provided on the base plate. The first opening of each of the plurality of discharge passages is arranged on the circumference of a first virtual circle centered on the axis of rotation, The second openings of each of the plurality of discharge passages are arranged on the circumference of a second virtual circle that has a larger diameter than the first virtual circle and is centered on the axis of rotation. Circuit board processing equipment.

8. A substrate processing apparatus according to claim 7, A third opening that opens on the upper surface side of the base plate at a position closer to the axis of rotation than the second opening, Equipped with, The aforementioned gas supply unit, A flow rate of the gas is supplied to the third opening at a rate smaller than the total flow rate of the gas flowing into each of the multiple discharge passages' first openings, and the gas is discharged from the third opening. Circuit board processing equipment.

9. A positioning step in which a substrate, which is positioned horizontally above the base plate, is positioned using positioning pins provided on the base plate, A discharge step in which gas flowing in from a first opening provided in the base plate is guided through a discharge passage to a second opening and discharged from the second opening to the upper surface side of the base plate, The rotation step involves rotating the base plate around a rotation axis that extends vertically, A process liquid supply step of supplying a processing liquid to the upper surface of the substrate, Equipped with, The direction in which the discharge passage extends from the first opening to the second opening is, when viewed from above, inclined downstream of the rotational direction of the base plate with respect to a virtual straight line passing through the rotation axis and the first opening. Substrate processing method.

Images