Substrate processing method

Abstract

To provide a technique capable of effectively reducing the rate of collapse of a pattern.SOLUTION: A substrate processing method includes a holding step, a liquid supplying step, a drying liquid supplying step, and a drying step. In the holding step, a substrate having a first main surface on which a pattern is formed and a second main surface on the opposite side to the first main surface is held. In the liquid supplying step, a processing liquid is supplied to the first main surface of the substrate. In the drying liquid supplying step, a drying liquid is supplied to the first main surface of the substrate after the liquid supplying step. In the drying step, the second main surface of the substrate is heated for a predetermined period of time after the drying liquid supplying step, and the substrate temperature of the first main surface of the substrate is set to be equal to or more than the substrate temperature in the drying liquid supplying step, thereby drying the substrate.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] Conventionally, single-wafer substrate processing apparatuses for processing substrates have been disclosed (for example, Patent Document 1). In Patent Document 1, the substrate processing apparatus supplies a rinsing liquid to the substrate, then supplies isopropyl alcohol, which has a lower surface tension than the rinsing liquid, to the substrate, and then dries the substrate. This prevents the pattern on the substrate from collapsing during drying. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-23182 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, Patent Document 1 does not consider the temperature of isopropyl alcohol, and therefore cannot effectively reduce the rate of pattern collapse.

[0005] Therefore, an object of the present disclosure is to provide a technique that can effectively reduce the rate of pattern collapse. [Means for solving the problem]

[0006] A first aspect is a substrate processing method comprising: a holding step of holding a substrate having a first main surface on which a pattern is formed and a second main surface opposite to the first main surface; a liquid supplying step of supplying a processing liquid to the first main surface of the substrate; a drying liquid supplying step of supplying a drying liquid to the first main surface of the substrate after the liquid supplying step; and a drying step of heating the second main surface of the substrate for a predetermined period of time after the drying liquid supplying step to make the substrate temperature of the first main surface of the substrate equal to or higher than the substrate temperature in the drying liquid supplying step, thereby drying the substrate.

[0007] A second aspect is the substrate processing method according to the first aspect, wherein the substrate temperature of at least a part of the first main surface of the substrate is set to a boiling point of the drying liquid or higher during the predetermined period.

[0008] A third aspect is a substrate processing method according to the first or second aspect, wherein in the drying liquid supply step, the second main surface of the substrate is heated with a first amount of heat per unit time, and in the specified period of the drying step, the second main surface of the substrate is heated with a second amount of heat per unit time that is greater than the first amount of heat.

[0009] A fourth aspect is the substrate processing method according to any one of the first to third aspects, further comprising supplying a heat medium to the second main surface of the substrate during the predetermined period.

[0010] A fifth aspect is a substrate processing method according to the third aspect, wherein in the drying liquid supply step, a heat medium obtained by mixing a high-temperature heat medium and a low-temperature heat medium having a lower temperature than the high-temperature heat medium is supplied to the second main surface of the substrate, and the mixing ratio of the high-temperature heat medium and the low-temperature heat medium is adjusted to supply the heat medium having a higher temperature than the heat medium in the drying liquid supply step to the second main surface of the substrate for at least the specified period of the drying step.

[0011] A sixth aspect is the substrate processing method according to the fourth or fifth aspect, wherein the heat medium having a temperature equal to or higher than a boiling point of the drying liquid is supplied to the second main surface of the substrate during the predetermined period.

[0012] A seventh aspect is a substrate processing method according to any one of the fourth to sixth aspects, wherein, in the drying liquid supplying process, the heat medium having a temperature equal to or higher than the boiling point of the drying liquid is supplied to the second main surface of the substrate, while the drying liquid is supplied at a flow rate such that the substrate temperature of the first main surface of the substrate is lower than the boiling point.

[0013] An eighth aspect is a substrate processing method according to any one of the fourth to seventh aspects, wherein the heat medium includes a liquid, and in the drying liquid supplying step, the drying liquid is supplied to the first main surface of the substrate while a shielding plate having an opposing surface facing the first main surface of the substrate is positioned at a shielding processing position, and during the specified period of the drying step, an inert gas is supplied toward the first main surface of the substrate from a gas outlet in the center of the shielding plate while the shielding plate is moved to a drying position closer to the first main surface than the shielding processing position.

[0014] A ninth aspect is the substrate processing method according to the eighth aspect, wherein the heated inert gas is supplied to the first main surface of the substrate during the predetermined period.

[0015] A tenth aspect is a substrate processing method according to the eighth or ninth aspect, wherein in the drying liquid supply process, the inert gas is supplied to the first main surface of the substrate through a gas flow path inside the blocking plate having an expanding flow path that expands toward the gas outlet, and the flow rate of the inert gas is increased while the blocking plate is moved from the blocking process position to the drying position.

[0016] An eleventh aspect is a substrate processing method according to the tenth aspect, wherein, in the drying liquid supplying process, the drying liquid is supplied to the first main surface of the substrate while the blocking plate is positioned at a first blocking processing position which is one of the blocking processing positions, and then, while supplying the drying liquid, the blocking plate is moved to a second blocking processing position which is one of the blocking processing positions and is closer to the first main surface of the substrate than the first blocking processing position.

[0017] A twelfth aspect is a substrate processing method according to any one of the first to eleventh aspects, wherein the substrate is rotated at a rotational speed higher than a rotational speed of the substrate in the drying liquid supplying step during the specified period of the drying step.

[0018] A thirteenth aspect is a substrate processing method according to any one of the first to twelfth aspects, wherein, in the drying liquid supply step, the second main surface of the substrate is heated only during a latter part of a drying liquid supply time during which the drying liquid is supplied. Effect of the Invention

[0019] According to the first aspect, the second main surface of the substrate is heated for a predetermined period of time. Therefore, the drying liquid can be evaporated in a state where the surface tension of the drying liquid is smaller and the evaporation rate is higher. Therefore, it is possible to prevent the pattern from collapsing when the first main surface of the substrate is dried.

[0020] According to the second aspect, the surface tension of the drying liquid can be further reduced for a predetermined period of time, and the evaporation rate of the drying liquid can be further increased, thereby further reducing the rate of pattern collapse.

[0021] According to the third aspect, in the drying liquid supplying step, the drying liquid is supplied to the first main surface of the substrate while the second main surface of the substrate is heated with a relatively small first heat quantity. Therefore, in a state in which the drying liquid is supplied, it is possible to suppress an increase in the substrate temperature and to suppress boiling of the drying liquid. Therefore, it is possible to suppress adhesion of particles. On the other hand, in a predetermined period of the drying step, in a state in which the drying liquid is not supplied to the substrate, the second main surface of the substrate is heated with a relatively large second heat quantity. Therefore, it is possible to further improve the evaporation rate while further reducing the surface tension of the drying liquid during the predetermined time. Therefore, it is possible to further reduce the collapse rate of the pattern.

[0022] According to the fourth aspect, the second main surface of the substrate can be heated easily.

[0023] According to the fifth aspect, since the mixture ratio is adjusted, the temperature of the heat medium supplied to the second main surface of the substrate can be raised quickly. Therefore, the temperature of the drying liquid can be raised at an earlier timing in the drying process. Therefore, the collapse rate of the pattern can be further reduced.

[0024] According to the sixth aspect, in the drying step, the surface tension of the drying liquid can be further reduced and the evaporation rate can be further increased, thereby further reducing the rate of pattern collapse.

[0025] According to the seventh aspect, in the drying liquid supplying step, the temperature of the first main surface of the substrate can be increased to a temperature closer to the boiling point of the drying liquid.

[0026] According to the eighth aspect, the shield plate is located at a dry position close to the substrate during the predetermined period. Therefore, the gap between the substrate and the shield plate can be narrowed, and the flow rate of the inert gas flowing outward in the radial direction from between the substrate and the shield plate can be increased. Therefore, the heat medium can be prevented from flowing from the second main surface to the first main surface via the periphery of the substrate.

[0027] According to the ninth aspect, the drying liquid can be evaporated in an even shorter time, which can further reduce the rate of pattern collapse.

[0028] According to the tenth aspect, it is possible to further reduce the rate of pattern collapse while suppressing adhesion of the drying liquid to the blocking plate.

[0029] According to the eleventh aspect, the blocking plate is located at the second blocking processing position immediately before the drying step. Therefore, the blocking plate can be moved to the drying position more quickly. Therefore, the substrate can be dried more quickly, and the pattern collapse rate can be further reduced.

[0030] According to the twelfth aspect, the drying liquid can be evaporated in an even shorter time, which can further reduce the rate of pattern collapse.

[0031] According to the thirteenth aspect, it is possible to reduce power consumption. [Brief description of the drawings]

[0032] [Figure 1] 1 is a plan view illustrating an example of a configuration of a substrate processing apparatus. [Diagram 2] 2 is a block diagram illustrating an example of an internal configuration of a control unit. FIG. [Diagram 3] FIG. 2 is a vertical cross-sectional view illustrating an example of the configuration of a processing unit according to the first embodiment. [Figure 4] 13 is a flowchart showing an example of an operation of a processing unit. [Diagram 5] 10A to 10C are diagrams each showing an example of a processing unit in each step; [Figure 6] 10A to 10C are diagrams each showing an example of a processing unit in each step; [Figure 7] 5A and 5B are diagrams showing typically an example of a timing chart of a processing unit and a change in temperature of a first main surface of a substrate over time. [Figure 8] FIG. 11 is a diagram illustrating an example of the configuration of a substrate heating part according to a second embodiment. [Figure 9] 13A to 13C are diagrams each showing a timing chart of a processing unit according to a second embodiment, and a schematic diagram showing an example of changes over time in the flow rate and temperature of a heat medium. [Figure 10] 13A and 13B are diagrams illustrating a timing chart of a processing unit according to a third embodiment and an example of a temperature change of a first main surface of a substrate. [Figure 11] 13A to 13C are diagrams each showing a timing chart of a processing unit according to a fourth embodiment, and a schematic diagram showing an example of changes over time in the flow rate of a heat medium, the temperature of the heat medium, and the temperature of a first main surface of a substrate. [Figure 12] 13 is a flowchart showing a first example of the operation of the processing unit according to the fifth embodiment. [Figure 13] 13 is a flowchart showing a second example of the operation of the processing unit according to the fifth embodiment. [Figure 14] 13 is a diagram illustrating a first example of the configuration of a blocking plate according to the sixth embodiment. FIG. [Figure 15] 10A and 10B are diagrams each showing an example of a state in which an inert gas is discharged; [Figure 16] FIG. 23 is a diagram showing a first example of a timing chart of a processing unit according to a sixth embodiment. [Figure 17] FIG. 23 is a diagram illustrating a second example of a timing chart of the processing unit according to the sixth embodiment. [Figure 18] 11A and 11B are diagrams illustrating an example of a processing unit in a drying liquid supplying step. [Figure 19] FIG. 23 is a diagram showing an example of the state of a processing unit in a drying liquid supplying step according to a sixth embodiment. [Figure 20] 13A and 13B are diagrams illustrating a second example of the configuration of the blocking plate according to the sixth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] Hereinafter, the embodiments will be described in detail with reference to the drawings. In the drawings, the dimensions and numbers of each part are exaggerated or simplified as necessary for the purpose of easy understanding. Parts having similar configurations and functions are given the same reference numerals, and duplicated explanations will be omitted in the following description.

[0034] In the following description, the same components are denoted by the same reference numerals, and their names and functions are also the same. Therefore, detailed descriptions thereof may be omitted to avoid duplication.

[0035] In addition, in the description below, even if ordinal numbers such as "first" or "second" are used, these terms are used for convenience to facilitate understanding of the contents of the embodiments, and are not limited to the ordering that may result from these ordinal numbers.

[0036] When an expression indicating a relative or absolute positional relationship (e.g., "in one direction," "along one direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.) is used, the expression not only strictly indicates the positional relationship, but also indicates a state in which the relative positional relationship is displaced with respect to angle or distance within a range in which a tolerance or similar function is obtained, unless otherwise specified. When an expression indicating an equal state (e.g., "same," "equal," "homogeneous," etc.) is used, the expression not only strictly indicates a quantitatively equal state, but also indicates a state in which a difference exists within a range in which a tolerance or similar function is obtained, unless otherwise specified. When an expression indicating a shape (e.g., "square shape" or "cylindrical shape," etc.) is used, the expression not only strictly indicates the shape geometrically, but also indicates a shape having, for example, unevenness or chamfering within a range in which a similar effect is obtained, unless otherwise specified. When an expression "comprises," "has," "includes," "includes," or "has" a component is used, the expression is not an exclusive expression that excludes the presence of other components. When the phrase "at least one of A, B, and C" is used, the phrase includes A only, B only, C only, any two of A, B, and C, and all of A, B, and C.

[0037] First Embodiment <Overall configuration of substrate processing apparatus> 1 is a plan view illustrating a schematic configuration of a substrate processing apparatus 100. The substrate processing apparatus 100 is a single-wafer processing apparatus that processes substrates W one by one.

[0038] The substrate W is, for example, a semiconductor wafer, a substrate for a liquid crystal display, a substrate for an organic EL (Electroluminescence), a substrate for an FPD (Flat Panel Display), a substrate for an optical display, a substrate for a magnetic disk, a substrate for an optical disk, a substrate for a magneto-optical disk, a substrate for a photomask, or a substrate for a solar cell. The substrate W has a thin flat plate shape having a first main surface Wa and a second main surface Wb. The second main surface Wb is the surface opposite to the first main surface Wa. In the following, the substrate W is assumed to be a semiconductor wafer. The substrate W has, for example, a disk shape. The diameter of the substrate W is, for example, about 300 mm, and the thickness of the substrate W is, for example, about 0.5 mm or more and about 3 mm or less. A pattern is formed on the main surface of the substrate W. The pattern here includes, for example, at least one of a wiring pattern, an electrode pattern, a semiconductor pattern, and an insulating pattern. The aspect ratio of the pattern is, for example, 5 or more and 500 or less. The pattern width is, for example, 3 nm or more and 50 nm or less. Such high aspect ratio patterns are prone to collapse.

[0039] 1, the substrate processing apparatus 100 includes an indexer block 110, a processing block 120, and a control unit 90. The processing block 120 is a section that mainly processes the substrate W, and the indexer block 110 is a section that mainly transports the substrate W between the outside of the substrate processing apparatus 100 and the processing block 120.

[0040] The indexer block 110 includes a load port 111 and a first transport part 112. A substrate container (hereinafter referred to as a carrier) C that is carried in from the outside is placed on the load port 111. A plurality of substrates W are accommodated in the carrier C, for example, arranged at intervals from each other in the vertical direction. In the example of Fig. 1, a plurality of load ports 111 are arranged.

[0041] The first transport unit 112 is a transport robot and can take out an unprocessed substrate W from a carrier C placed on each load port 111. The first transport unit 112 can also be called an indexer robot. The first transport unit 112 transports the unprocessed substrate W taken out from the carrier C to the processing block 120. The processing block 120 can process the unprocessed substrate W. The first transport unit 112 can also receive a processed substrate W from the processing block 120 and transport the processed substrate W to a carrier C of the load port 111.

[0042] In the example of FIG. 1, the processing block 120 includes a plurality of processing units 1 and a second transport section 122. The second transport section 122 is a transport robot and can transport the substrate W between the first transport section 112 and the plurality of processing units 1. In the example of FIG. 1, the processing block 120 also includes a placement section 123. The placement section 123 is, for example, a shelf on which a plurality of substrates W can be placed in a vertically aligned state. The first transport section 112 places an unprocessed substrate W on the placement section 123. The second transport section 122 takes out the unprocessed substrate W from the placement section 123 and transports the substrate W to the processing unit 1. The processing unit 1 processes the substrate W. The configuration of the processing unit 1 will be described later. The second transport section 122 takes out the processed substrate W from the processing unit 1 and transports the substrate W to the placement section 123. The first transport section 112 takes out the substrate W from the platform 123 and transports the substrate W to the carrier C of the load port 111 .

[0043] 1, a plurality of (e.g., four) processing units 1 are provided so as to surround the second transport section 122 in a plan view. This second transport section 122 may also be called a center robot. At each position in a plan view, a plurality of processing units 1 may be stacked in the vertical direction. In other words, a plurality of towers TW (four in the figure) each of which is made up of a plurality of processing units 1 stacked in the vertical direction may be provided so as to surround the second transport section 122.

[0044] The control unit 90 performs overall control of the substrate processing apparatus 100. Specifically, the control unit 90 controls the first transport unit 112, the second transport unit 122, and the processing unit 1. FIG. 2 is a block diagram showing an example of the internal configuration of the control unit 90. The control unit 90 is an electronic circuit, and has, for example, a data processing unit 91 and a storage unit 92. In the specific example of FIG. 2, the data processing unit 91 and the storage unit 92 are connected to each other via a bus 93. The data processing unit 91 may be, for example, an arithmetic processing device such as a CPU (Central Processor Unit). The storage unit 92 may have a non-transient storage unit (for example, a ROM (Read Only Memory)) 921 and a temporary storage unit (for example, a RAM (Random Access Memory)) 922. The non-transient storage unit 921 may store, for example, a program that specifies the processing to be executed by the control unit 90. The data processing unit 91 executes this program, so that the control unit 90 can execute the processing specified in the program. Of course, a part or all of the processing executed by the control unit 90 may be executed by hardware such as a dedicated logic circuit.

[0045] <Processing unit overview> Fig. 3 is a vertical cross-sectional view illustrating an example of the configuration of the processing unit 1 according to the first embodiment. It is not necessary that all processing units 1 in the substrate processing apparatus 100 have the configuration illustrated in Fig. 3. It is sufficient that at least one processing unit 1 in the substrate processing apparatus 100 has the configuration illustrated in Fig. 3.

[0046] The processing unit 1 includes a substrate holder 2 , at least one nozzle 3 , and a substrate heater 40 .

[0047] 3, the processing unit 1 is also provided with a chamber 10. The chamber 10 has a box-like shape, and its internal space corresponds to a processing space for processing the substrate W. The chamber 10 is provided with an openable / closable loading / unloading port (not shown). The second transport part 122 loads an unprocessed substrate W into the chamber 10 through the loading / unloading port, and loads a processed substrate W out of the chamber 10 through the loading / unloading port.

[0048] In the example of Fig. 3, a fan filter unit 11 is provided on the ceiling of the chamber 10. The fan filter unit 11 takes in air from outside the chamber 10, purifies it, and sends the purified air into the chamber 10. Operation of the fan filter unit 11 creates a downflow of clean air in the chamber 10. In the example of Fig. 3, the upstream end of an exhaust pipe 13 is connected to the lower part of the side wall of the chamber 10. Gas in the chamber 10 is exhausted to the outside through the exhaust pipe 13.

[0049] The substrate holding unit 2 is provided in the chamber 10, and rotates the substrate W around a rotation axis Q1 while holding the substrate W in a horizontal position. The horizontal position here means that the thickness direction of the substrate W is aligned along the vertical direction. The rotation axis Q1 is an axis that passes through the center of the substrate W and is aligned along the vertical direction. Such a substrate holding unit 2 may also be called a spin chuck.

[0050] Here, the first main surface Wa of the substrate W on which the pattern is formed faces vertically upward. That is, in the example of Fig. 3, the first main surface Wa of the substrate W held by the substrate holding part 2 corresponds to the upper surface. The pattern includes, for example, at least one of a wiring pattern, an insulating pattern, and a semiconductor pattern.

[0051] In the example of FIG. 3, the substrate holding unit 2 includes a spin base 21, chuck pins 22, and a rotation drive unit 23. The spin base 21 has a plate-like shape (for example, a disk shape) and is provided with its thickness direction aligned along the vertical direction. A plurality of chuck pins 22 are provided on the upper surface of the spin base 21. The plurality of chuck pins 22 are provided at equal intervals along the circumferential direction about the rotation axis Q1. The plurality of chuck pins 22 are provided so as to be displaceable between a holding position and a release position, which will be described next. The holding position is a position where the chuck pins 22 abut against the periphery of the substrate W. The plurality of chuck pins 22 hold the substrate W by stopping at the respective holding positions. FIG. 3 shows the chuck pins 22 stopped at the holding position. The release position is a position where each chuck pin 22 is separated from the substrate W. The plurality of chuck pins 22 stop at the respective release positions, whereby the holding of the substrate W by the plurality of chuck pins 22 is released. The substrate holding unit 2 also includes a pin driving unit (not shown) that displaces the chuck pins 22. The pin driving unit includes a driving source such as a motor and an air cylinder, and is controlled by the control unit 90.

[0052] The rotation drive unit 23 includes a shaft 231 and a motor 232. The upper end of the shaft 231 is connected to the lower surface of the spin base 21, and the shaft 231 extends from the lower surface of the spin base 21 along a rotation axis Q1. The motor 232 is controlled by the control unit 90 to rotate the shaft 231 about the rotation axis Q1. As a result, the spin base 21, the chuck pins 22, and the substrate W rotate together about the rotation axis Q1.

[0053] It is not essential that the substrate holding portion 2 has the chuck pin 22. For example, the substrate holding portion 2 may hold the substrate W by a chuck method such as a vacuum chuck, an electrostatic chuck, or a Bernoulli chuck.

[0054] At least one nozzle 3 ejects liquid toward a first main surface Wa of the substrate W held by the substrate holding part 2. In the example of FIG. 3, since the first main surface Wa is the upper surface, the nozzle 3 is provided vertically above the substrate W held by the substrate holding part 2.

[0055] In the example of Fig. 3, nozzles 3c, 3w, and 3i are provided as nozzles 3. Nozzle 3c ejects a chemical liquid, nozzle 3w ejects a rinsing liquid, and nozzle 3i ejects a drying liquid. Specific examples of the chemical liquid, rinsing liquid, and drying liquid will be described later. In the following, the chemical liquid, rinsing liquid, and drying liquid are also collectively referred to as processing liquid. Nozzle 3 is, for example, a straight nozzle that ejects the processing liquid in a continuous flow state.

[0056] In the example of Fig. 3, the nozzle 3 is provided so as to be movable by the movement drive unit 35. In the example of Fig. 3, movement drive unit 35c, movement drive unit 35w, and movement drive unit 35i are shown as the movement drive unit 35. The movement drive unit 35c moves the nozzle 3c, the movement drive unit 35w moves the nozzle 3w, and the movement drive unit 35i moves the nozzle 3i.

[0057] The movement driver 35c moves the nozzle 3c between a first processing position and a first waiting position, which will be described below. The first waiting position is a position where the nozzle 3c does not discharge the chemical liquid toward the first main surface Wa of the substrate W, and is, for example, a position radially outward from the substrate holder 2. The example of FIG. 3 shows the nozzle 3c stopped at the first waiting position. The first processing position is a position where the nozzle 3c discharges the chemical liquid toward the first main surface Wa of the substrate W, and is, for example, a position vertically facing the center of the first main surface Wa of the substrate W.

[0058] The movement driver 35w moves the nozzle 3w between a second processing position and a second waiting position, which will be described next. The second processing position is a position where the nozzle 3w ejects the rinsing liquid toward the first main surface Wa of the substrate W, and is, for example, a position vertically opposed to the center of the first main surface Wa of the substrate W. The example of FIG. 3 shows the nozzle 3w stopped at the second processing position. The second waiting position is a position where the nozzle 3w does not eject the rinsing liquid toward the first main surface Wa of the substrate W, and is, for example, a position radially outward from the substrate holder 2.

[0059] FIG. 3 shows an example of a specific configuration of the moving drive unit 35w. In the example of FIG. 3, the moving drive unit 35w includes an arm 351, a support column 352, and a driving source 353. The support column 352 is provided radially outward from the guard 7 described later and extends along the vertical direction. The arm 351 extends along the horizontal direction, its tip end is connected to the nozzle 3w, and its base end is connected to the support column 352. The driving source 353 is controlled by the control unit 90 and rotates the support column 352 in a forward and reverse direction around its central axis Q2 within a predetermined angle range. The driving source 353 includes, for example, a motor. When the support column 352 rotates in a forward and reverse direction around the central axis Q2 within a predetermined angle range, the nozzle 3w reciprocates along the circumferential direction about the central axis Q2. The support column 352 is installed so that the second processing position and the second standby position are located on the movement trajectory of the nozzle 3w. The movement driver 35w is not necessarily limited to the embodiment shown in Fig. 3, and may include, for example, a linear motion mechanism such as a linear motor. The movement driver 35c may have, for example, the same configuration as the movement driver 35w.

[0060] The movement drive unit 35i moves the nozzle 3i between a blocking processing position and a blocking standby position, which will be described next. In the example of FIG. 3, the nozzle 3i is provided integrally with a blocking plate 6, which will be described later, and the movement drive unit 35i moves the nozzle 3i and the blocking plate 6 together. The blocking processing position is a position where the nozzle 3i ejects the drying liquid toward the first main surface Wa of the substrate W, and is, for example, a position facing the center of the first main surface Wa of the substrate W in the vertical direction. The blocking standby position is a position where the nozzle 3i does not eject the drying liquid toward the first main surface Wa of the substrate W, and is, for example, a position vertically above the blocking processing position. In the example of FIG. 3, the nozzle 3i and the blocking plate 6 stopped at the blocking standby position are shown. The movement drive unit 35i moves the nozzle 3i along the vertical direction, and therefore can also be said to be an elevation drive unit. The movement drive unit 35i includes a drive source such as a motor and a power transmission unit that transmits power from the drive source to the nozzle 3i and the blocking plate 6. The power transmission unit includes, for example, a cam mechanism or a ball screw mechanism.

[0061] The nozzle 3 is connected to the downstream end of the supply pipe 31, and the upstream end of the supply pipe 31 is connected to a processing liquid supply source. In the example of FIG. 3, supply pipes 31c, 31w, and 31i are shown as the supply pipe 31. The downstream end of the supply pipe 31c is connected to the nozzle 3c, and the upstream end of the supply pipe 31c is connected to a chemical supply source. The chemical supply source has a tank (not shown) for storing the chemical, and supplies the chemical to the upstream end of the supply pipe 31c. As the chemical, for example, a liquid such as hydrofluoric nitric acid obtained by mixing hydrofluoric acid, nitric acid, and water, a hydrofluoric acid-hydrogen peroxide aqueous solution (FPM) obtained by mixing hydrofluoric acid, hydrogen peroxide, and water, tetramethylammonium hydroxide (TMAH), a mixture of sulfuric acid and hydrogen peroxide (SPM), ammonia water, a mixture of ammonia, hydrogen peroxide, and water (SC-1), and a mixture of hydrogen chloride, hydrogen peroxide, and water (SC-2) can be used. The chemical solution does not have to be a mixture, but may be a single solution, such as hydrofluoric acid (HF), hydrogen peroxide, or sulfuric acid.

[0062] The downstream end of the supply pipe 31w is connected to the nozzle 3w, and the upstream end of the supply pipe 31w is connected to a rinse liquid supply source. The rinse liquid supply source has a tank (not shown) for storing the rinse liquid, and supplies the rinse liquid to the upstream end of the supply pipe 31w. For example, pure water, carbon dioxide water, or ozone water can be used as the rinse liquid.

[0063] The downstream end of the supply pipe 31i is connected to the nozzle 3i, and the upstream end of the supply pipe 31i is connected to a drying liquid supply source. The drying liquid supply source has a tank (not shown) that stores the drying liquid, and supplies the drying liquid to the upstream end of the supply pipe 31i. For example, an organic solvent such as isopropyl alcohol can be used as the drying liquid. The surface tension of the drying liquid is lower than the surface tension of other processing liquids (for example, both the surface tension of the chemical liquid and the surface tension of the rinsing liquid). In addition, the volatility of the drying liquid is higher than the volatility of other processing liquids (for example, both the volatility of the chemical liquid and the volatility of the rinsing liquid).

[0064] A supply valve 32 and a flow rate adjustment valve 33 are inserted in the supply pipe 31. In the example of Fig. 3, a supply valve 32c and a flow rate adjustment valve 33c are inserted in the supply pipe 31c, a supply valve 32w and a flow rate adjustment valve 33w are inserted in the supply pipe 31w, and a supply valve 32i and a flow rate adjustment valve 33i are inserted in the supply pipe 31i. The supply valve 32 switches between opening and closing the supply pipe 31. The flow rate adjustment valve 33 adjusts the flow rate of the processing liquid flowing through the supply pipe 31. The flow rate adjustment valve 33 may be a mass flow controller. The supply valve 32 and the flow rate adjustment valve 33 are controlled by a control unit 90.

[0065] When the supply valve 32 opens while the substrate holder 2 is rotating the substrate W and the nozzle 3 is located at the processing position, a processing liquid is discharged from the nozzle 3 toward the first main surface Wa of the substrate W that is rotating. The processing liquid that has landed on the first main surface Wa of the substrate W receives centrifugal force accompanying the rotation of the substrate W, flows radially outward along the first main surface Wa, and is scattered outward from the periphery of the substrate W. As a result, processing according to the type of processing liquid is performed on the first main surface Wa of the substrate W. For example, when a cleaning chemical liquid is discharged, the first main surface Wa of the substrate W is cleaned by the chemical liquid.

[0066] The substrate heating unit 40 heats the second main surface Wb of the substrate W held by the substrate holding unit 2. In the example of Fig. 3, the substrate heating unit 40 is provided at a position vertically facing the second main surface Wb of the substrate W. In the example of Fig. 3, the second main surface Wb of the substrate W corresponds to the lower surface, so the substrate heating unit 40 is provided directly below the substrate W.

[0067] In the example of FIG. 3, the substrate heating unit 40 includes a nozzle 4. The nozzle 4 ejects a heat medium toward the second main surface Wb of the substrate W. In the example of FIG. 3, the second main surface Wb of the substrate W corresponds to the bottom surface, so the nozzle 4 may also be called a bottom nozzle. In the example of FIG. 3, a through hole is formed in the center of the spin base 21 of the substrate holding unit 2, and the shaft 231 is a hollow shaft. The through hole of the spin base 21 and the hollow part of the shaft 231 are connected in the vertical direction. A part of the nozzle 4 is disposed in the through hole. An ejection port is formed in the upper surface of the nozzle 4, and the ejection port of the nozzle 4 faces the center of the second main surface Wb of the substrate W in the vertical direction. The nozzle 4 ejects a heat medium toward the center of the second main surface Wb of the substrate W.

[0068] The downstream end of a supply pipe 41 is connected to the nozzle 4. The supply pipe 41 extends inside the shaft 231 and penetrates the shaft 231. The upstream end of the supply pipe 41 is connected to a heat medium supply source. The heat medium is a fluid (gas or liquid), and a more specific example is a liquid such as water. The heat medium supply source has, for example, a tank (not shown) that stores the heat medium, and supplies the heat medium to the upstream end of the supply pipe 41.

[0069] In the example of FIG. 3, supply pipe 41 is provided with supply valve 42, flow rate adjustment valve 43, and heater 44. Supply valve 42 switches supply pipe 41 between open and closed states. Flow rate adjustment valve 43 adjusts the flow rate of the heat medium flowing through supply pipe 41. Flow rate adjustment valve 43 may be a mass flow controller. Heater 44 heats the heat medium flowing through supply pipe 41. Heater 44 may be, for example, an electric resistance heater having an electric heating wire. Supply valve 42, flow rate adjustment valve 43, and heater 44 are controlled by control unit 90.

[0070] When the supply valve 42 opens, a high-temperature heat medium is discharged from the nozzle 4 onto the central portion of the second main surface Wb of the rotating substrate W. The heat medium that has landed on the central portion of the second main surface Wb of the substrate W receives centrifugal force accompanying the rotation of the substrate W, flows radially outward along the second main surface Wb, and is scattered outward from the periphery of the substrate W. As the high-temperature heat medium flows along the second main surface Wb of the substrate W, heat is transferred from the heat medium to the substrate W, and the substrate W is heated.

[0071] In the example of FIG. 3, the processing unit 1 is provided with a guard 7 and a guard lifting drive 71. The guard 7 has a cylindrical shape with the rotation axis Q1 as the central axis, and surrounds the substrate holder 2. The guard 7 can receive the processing liquid and heat medium splashed from the periphery of the substrate W. The guard lifting drive 71 raises and lowers the guard 7 between an upper position and a lower position, which will be described below. The upper position is a position where the upper end of the guard 7 is vertically above the substrate W held by the substrate holder 2. When the guard 7 is located at the upper position, it can receive the processing liquid and heat medium splashed from the periphery of the substrate W. The lower position is a position lower than the upper position, for example, a position where the upper end of the guard 7 is vertically below the upper surface of the spin base 21.

[0072] In the example of FIG. 3, multiple guards 7 are provided. The multiple guards 7 are arranged concentrically. The multiple guards 7 may be used differently depending on the type of processing liquid. In the example of FIG. 3, cups 72 corresponding to each guard 7 are provided. The cups 72 have an annular (e.g., annular) recess (groove) surrounding the rotation axis Q1. Each cup 72 receives the processing liquid that has flowed down the inner circumferential surface of the corresponding guard 7. The upstream end of the discharge pipe 12 is connected to, for example, the bottom of each cup 72. The processing liquid received in each cup 72 is discharged to the outside of the processing unit 1 through the discharge pipe 12.

[0073] In the example of FIG. 3, the processing unit 1 further includes a shield plate 6. The shield plate 6 is provided at a position vertically facing the first main surface Wa of the substrate W held by the substrate holder 2. In the example of FIG. 3, the first main surface Wa of the substrate W corresponds to the upper surface, so the shield plate 6 is provided vertically above the substrate W. The shield plate 6 has, for example, a plate shape, and is provided with its thickness direction along the vertical direction. The lower surface of the shield plate 6 is an opposing surface facing the first main surface Wa of the substrate W. The shield plate 6 has, for example, a circular shape in a plan view. The diameter of the shield plate 6 (i.e., the diameter of the opposing surface) may be, for example, 80% or more of the diameter of the substrate W, 90% or more, or may be equal to or greater than the diameter of the substrate W. A through hole is formed in the center of the shield plate 6, penetrating the shield plate 6 in the vertical direction, and the nozzle 3i is provided inside the through hole.

[0074] 3, a hollow shaft 61 is provided on the upper surface of the blocking plate 6. The hollow shaft 61 has a hollow portion, which is vertically connected to a through hole of the blocking plate 6. The diameter of the outer peripheral surface of the nozzle 3i is smaller than the diameters of the hollow shaft 61 and the inner peripheral surfaces of the blocking plate 6. The space between the outer peripheral surface of the nozzle 3i and the inner peripheral surfaces of the hollow shaft 61 and the blocking plate 6 functions as a gas flow path 3g as described below.

[0075] In the example of FIG. 3, the upper part of the hollow shaft 61 is connected to the downstream end of the supply pipe 31g. In other words, the downstream end of the supply pipe 31g is connected to the gas flow passage 3g between the outer peripheral surface of the nozzle 3i and the inner peripheral surfaces of the hollow shaft 61 and the blocking plate 6. The upstream end of the supply pipe 31g is connected to a gas supply source. The gas supply source has a storage section (not shown) for storing an inert gas, and supplies the inert gas to the upstream end of the supply pipe 31g. The inert gas includes, for example, at least one of nitrogen gas and a rare gas. The rare gas includes, for example, argon gas.

[0076] Supply pipe 31g is provided with supply valve 32g, flow rate adjustment valve 33g, and heater 34g. Supply valve 32g switches supply pipe 31g between open and closed states. Flow rate adjustment valve 33g adjusts the flow rate of the inert gas flowing through supply pipe 31g. Heater 34g heats the inert gas flowing through supply pipe 31g. Heater 34g may be, for example, an electric resistance heater having a heating wire. Supply valve 32g, flow rate adjustment valve 33g, and heater 34g are controlled by controller 90.

[0077] When the supply valve 32g is opened and the heater 34g is operated, a high-temperature inert gas is discharged from the center of the lower surface of the shield plate 6 (i.e., the lower end port of the gas flow path 3g) toward the center of the first main surface Wa of the substrate W. This can promote drying of the substrate W.

[0078] <Operation example of substrate processing apparatus> Next, an example of the operation of the processing unit 1 will be described. Fig. 4 is a flow chart showing an example of the operation of the processing unit 1. The control unit 90 causes the processing unit 1 to execute the processes from step S1 to step S7 according to a preset processing procedure (recipe). Figs. 5 and 6 are diagrams that roughly show an example of the state of the processing unit 1 at each step.

[0079] First, the second transport part 122 transports the substrate W to the processing unit 1. Then, the substrate holding part 2 holds the substrate W received from the second transport part 122 (step S1: holding step). As a specific example, the substrate holding part 2 displaces the multiple chuck pins 22 from their respective release positions to their holding positions. As a result, the multiple chuck pins 22 hold the substrate W. The substrate holding part 2 continues to hold the substrate W until the processing of the substrate W is completed.

[0080] Next, the substrate holding part 2 starts rotating the substrate W (step S2: rotation start step). The substrate holding part 2 may continue rotating the substrate W until the processing of the substrate W is completed.

[0081] Next, the processing unit 1 supplies the chemical liquid to the first main surface Wa of the substrate W (Step S3: Chemical liquid step). First, the movement drive unit 35c moves the nozzle 3c to the first processing position. Also, the guard lift drive unit 71 raises the guard 7 for the chemical liquid to the upper position. Then, the control unit 90 opens the supply valve 32c. That is, the control unit 90 switches the supply valve 32c from a closed state to an open state. As a result, the chemical liquid is discharged from the nozzle 3c toward the first main surface Wa of the substrate W during rotation. The chemical liquid that has landed on the first main surface Wa of the substrate W flows radially outward due to the centrifugal force accompanying the rotation of the substrate W, and is scattered from the periphery of the substrate W. At this time, the chemical liquid acts on the first main surface Wa of the substrate W, and a chemical liquid process according to the type of the chemical liquid is performed on the first main surface Wa of the substrate W. For example, the processing unit 1 performs a cleaning process for cleaning and removing impurities on the first main surface Wa of the substrate W, or an etching process for etching a predetermined film on the first main surface Wa of the substrate W. The chemical solution scattered from the periphery of the substrate W is received by the guard 7 and discharged to the outside of the chamber 10 through the discharge pipe 12.

[0082] When the substrate W has been sufficiently processed, the control unit 90 closes the supply valve 32c. As a specific example, the control unit 90 measures the elapsed time from the start of the discharge of the chemical liquid, and judges whether the elapsed time is equal to or longer than a predetermined chemical liquid time. The chemical liquid time is set in advance to a time that allows the chemical liquid processing to be sufficiently performed. The elapsed time is measured, for example, by a timer circuit (not shown) belonging to the control unit 90. When the elapsed time is equal to or longer than the chemical liquid time, the control unit 90 switches the supply valve 32c from an open state to a closed state. After closing the supply valve 32c, the movement drive unit 35c moves the nozzle 3c to the first standby position.

[0083] Next, the processing unit 1 supplies the rinse liquid to the first main surface Wa of the substrate W (step S4: rinse step). Specifically, first, the movement drive unit 35w moves the nozzle 3w to the second processing position. Also, when the guard 7 for the rinse liquid is different from the guard 7 for the chemical liquid, the guard lift drive unit 71 lifts and lowers the guard 7 appropriately to position the guard 7 for the rinse liquid at the upper position. Then, the control unit 90 opens the supply valve 32w. That is, the control unit 90 switches the supply valve 32w from the closed state to the open state. As a result, as shown in FIG. 5(a), the rinse liquid is discharged from the nozzle 3w toward the first main surface Wa of the substrate W during rotation. The rinse liquid that has landed on the first main surface Wa of the substrate W flows radially outward due to the centrifugal force accompanying the rotation of the substrate W, and is scattered from the periphery of the substrate W. At this time, the rinse liquid pushes the chemical liquid on the first main surface Wa of the substrate W radially outward. As a result, the processing liquid on the first main surface Wa of the substrate W is replaced with the rinsing liquid from the chemical liquid. The processing liquid splashed from the periphery of the substrate W is received by the guard 7 and discharged to the outside of the chamber 10 through the discharge pipe 12.

[0084] When the chemical liquid has been sufficiently replaced with the rinsing liquid, the control unit 90 closes the supply valve 32w. As a specific example, the control unit 90 measures the elapsed time from the start of discharge of the rinsing liquid, and switches the supply valve 32w from an open state to a closed state when the elapsed time is equal to or longer than a predetermined rinsing time. The rinsing time is preset to a time that allows the chemical liquid to be sufficiently replaced with the rinsing liquid. After the supply valve 32w is closed, the movement drive unit 35w moves the nozzle 3w to the second standby position.

[0085] Next, the processing unit 1 supplies the drying liquid to the first main surface Wa of the substrate W (Step S5: drying liquid supply step). Specifically, first, the movement drive unit 35i moves the nozzle 3i and the blocking plate 6 together to the blocking processing position. Furthermore, if the guard 7 for the drying liquid is different from the guard 7 for the rinsing liquid, the guard lift drive unit 71 lifts and lowers the guard 7 appropriately to raise the guard 7 for the drying liquid to the upper position. Then, the control unit 90 opens the supply valve 32i. That is, the control unit 90 switches the supply valve 32i from a closed state to an open state.

[0086] When the supply valve 32i is opened, as shown in FIG. 5(b), the drying liquid is discharged from the nozzle 3i toward the first main surface Wa of the rotating substrate W. The temperature of the drying liquid may be, for example, room temperature (for example, about 25 degrees Celsius). The drying liquid that has landed on the first main surface Wa of the substrate W flows radially outward due to the centrifugal force caused by the rotation of the substrate W, and splashes from the periphery of the substrate W. At this time, the drying liquid pushes away the rinsing liquid on the first main surface Wa of the substrate W, so that the processing liquid on the first main surface Wa of the substrate W is replaced from the rinsing liquid to the drying liquid. The processing liquid that has splashed from the periphery of the substrate W is received by the guard 7 and discharged to the outside of the chamber 10 through the discharge pipe 12. The rotation speed of the substrate W in the drying liquid supply step may be set to, for example, 150 rpm or more and 600 rpm or less, or 200 rpm or more and 400 rpm or less. As a more specific example, the rotation speed may be set to 300 rpm.

[0087] The processing unit 1 may also heat the substrate W when the drying liquid is supplied. That is, the substrate heating section 40 may heat the second main surface Wb of the substrate W. As a more specific example, the control section 90 may open the supply valve 42 and operate the heater 44. According to this, as shown in FIG. 5(b), a high-temperature heat medium (e.g., hot water) is discharged from the nozzle 4 toward the second main surface Wb of the substrate W during rotation. The heater 44 may heat the temperature of the heat medium to, for example, 60 degrees Celsius or higher, 70 degrees Celsius or higher, or 80 degrees Celsius or higher. The heater 44 may also adjust the temperature of the heat medium to, for example, below the boiling point of the drying liquid. The temperature of the heat medium here is, for example, the temperature of the heat medium at the discharge port of the nozzle 4. The flow rate adjustment valve 43 may adjust the flow rate of the heat medium to, for example, a value greater than the flow rate of the drying liquid. More specifically, the flow rate regulating valve 43 may adjust the flow rate of the heat medium to 1000 mL (milliliters) / min or more, or to 1500 mL / min or more.

[0088] The heat medium that has landed in the center of the second main surface Wb of the substrate W flows radially outward due to centrifugal force accompanying the rotation of the substrate W, and is scattered from the periphery of the substrate W. As the high-temperature heat medium flows along the second main surface Wb of the substrate W, heat is transferred from the heat medium to the substrate W, heating the substrate W. The heat of the substrate W is transferred to the drying liquid on the first main surface Wa. As a result, the drying liquid on the first main surface Wa of the substrate W is also heated, and its temperature rises.

[0089] When the rinsing liquid is sufficiently replaced with the drying liquid, the processing unit 1 dries the substrate W (step S6: drying process). Specifically, the processing unit 1 measures the elapsed time from the start of the discharge of the drying liquid, and judges whether the elapsed time is equal to or longer than a predetermined drying liquid supply time. The drying liquid supply time is set in advance to a time sufficient for the rinsing liquid to be sufficiently replaced with the drying liquid. The drying liquid supply time may be set, for example, to about several tens of seconds, specifically, to about 40 seconds. Then, when the elapsed time is equal to or longer than the drying liquid supply time, the processing unit 1 dries the substrate W. Specifically, the control unit 90 closes the supply valve 32i, opens the supply valve 32g, operates the heater 34g, causes the movement drive unit 35i to lower the blocking plate 6 to a drying position closer to the substrate W than the blocking processing position, and causes the substrate holder 2 to increase the rotation speed of the substrate W.

[0090] When the supply valve 32g is opened, as shown in FIG. 6(a), a high-temperature inert gas is discharged toward the first main surface Wa of the substrate W from a gas discharge port (i.e., a lower end port of the gas flow path 3g) at the center of the lower surface of the shield plate 6. In FIG. 6, the flow direction of the inert gas is shown typically by an arrow just below the shield plate 6. The heater 34g may heat the inert gas to, for example, 60 degrees Celsius or higher, 70 degrees Celsius or higher, or 80 degrees Celsius or higher. The temperature of the inert gas may be, for example, the temperature of the inert gas at the gas discharge port of the gas flow path 3g. The flow rate adjustment valve 33g may adjust the flow rate of the inert gas to, for example, 10 L (liters) / min or more and 300 L / min or less.

[0091] In FIG. 6(a), the blocking plate 6 is shown to be descending as a block arrow next to the blocking plate 6. Here, the movement drive unit 35i moves the nozzle 3i and the blocking plate 6 downward together while the inert gas is being discharged from the gas flow path 3g. When the blocking plate 6 is lowered to the drying position, the gap between the blocking plate 6 and the first main surface Wa of the substrate W can be narrowed as shown in FIG. 6(b). That is, the gap between the blocking plate 6 and the substrate W in the drying step can be narrower than the gap between the blocking plate 6 and the substrate W in the drying liquid supply step. Therefore, in the drying step, the flow rate of the inert gas flowing outward in the radial direction from the periphery between the blocking plate 6 and the substrate W can be increased. The gap between the lower surface of the blocking plate 6 and the first main surface Wa of the substrate W in the drying step is set to, for example, about several mm (for example, 5 mm) or less.

[0092] The substrate holding part 2 may increase the rotation speed of the substrate W monotonically and non-decreasingly without reducing it during the transition from the drying liquid supplying step to the drying step and at the beginning of the drying step. The substrate holding part 2 may rotate the substrate W at a rotation speed of, for example, 800 rpm or more and 2500 rpm or less, or may rotate the substrate W at a rotation speed of 800 rpm or more and 1500 rpm or less. Furthermore, the substrate holding part 2 may gradually (for example, stepwise) increase the rotation speed of the substrate W during or after the shielding plate 6 is lowered.

[0093] The increased rotation speed can increase the amount of drying liquid scattered from the periphery of the substrate W. This allows the drying liquid to evaporate while keeping the film of the drying liquid on the first main surface Wa thin. This allows the drying liquid to evaporate in a shorter time.

[0094] On the other hand, when the rotation speed of the substrate W increases, the heat medium is more likely to flow from the second main surface Wb of the substrate W through the periphery to the peripheral portion of the first main surface Wa. However, in the above example, the inert gas flows outward in the radial direction from between the blocking plate 6 and the substrate W at a high flow rate. Therefore, the inert gas can push the heat medium back outward in the radial direction. Therefore, the flow of the heat medium can be suppressed or prevented. In other words, the distance between the blocking plate 6 and the substrate W and the flow rate of the inert gas can be set to a degree that can sufficiently suppress the flow of the heat medium.

[0095] When the drying liquid has sufficiently evaporated, the substrate heating unit 40 stops heating the substrate W. As a specific example, the control unit 90 measures the time that has elapsed since the discharge of the drying liquid was stopped, and determines whether the measured time is equal to or longer than a predetermined evaporation time. The evaporation time is set in advance to a time that allows the first main surface Wa of the substrate W to be sufficiently dried. When the elapsed time is equal to or longer than the evaporation time, the control unit 90 switches the supply valve 42 from an open state to a closed state. This stops the supply of the heat medium to the second main surface Wb of the substrate W. In other words, the heating of the substrate W by the substrate heating unit 40 stops.

[0096] Then, the control unit 90 stops the rotation of the substrate W, for example, when a predetermined drying time sufficient for drying the second main surface Wb of the substrate W has elapsed. Also, the movement drive unit 35i raises the nozzle 3i and the blocking plate 6 together to the blocking standby position, and the guard lift drive unit 71 lowers the guard 7 to the lower position.

[0097] Next, the substrate holder 2 releases the substrate W from its hold (step S7: hold releasing step). Then, the second transporter 122 carries the processed substrate W out of the processing unit 1.

[0098] As described above, the processing unit 1 can process the substrate W. Moreover, in this embodiment, after the supply of the drying liquid is stopped, the substrate heating part 40 heats the second main surface Wb of the substrate W (drying process, FIG. 6). Therefore, in the drying process, the drying liquid on the first main surface Wa of the substrate W can evaporate at a higher temperature.

[0099] 7 is a diagram showing a timing chart of the processing unit 1 and an example of a change in temperature (hereinafter referred to as substrate temperature) over time of the first main surface Wa of the substrate W. In the example of FIG. 7, at time t1, the control unit 90 switches the supply valve 32i and the supply valve 42 from a closed state to an open state. Therefore, at time t1, the nozzle 3i starts to discharge the drying liquid, and the nozzle 4 starts to discharge the high-temperature heat medium. This discharge of the drying liquid essentially starts the drying liquid supply step (step S5). Furthermore, the discharge of the heat medium causes the substrate temperature of the first main surface Wa of the substrate W to rise over time. The substrate temperature rises at a high rate of increase to a certain extent, and then rises slowly or may converge.

[0100] 7, at time t2 after time t1, the control unit 90 switches the supply valve 32i from the open state to the closed state. As a result, the discharge of the drying liquid stops at time t2. This cessation of the discharge of the drying liquid essentially ends the drying liquid supplying process.

[0101] On the other hand, in the example of FIG. 7, the supply valve 42 continues to be open even after time t2. Therefore, during the evaporation time after time t2 (corresponding to the time from time t2 to time t3 in FIG. 7: a predetermined period), the nozzle 4 discharges the heat medium, and the substrate W continues to receive heat from the heat medium. Therefore, the substrate temperature of the first main surface Wa of the substrate W during the evaporation time can be made higher than the substrate temperature when the drying liquid is supplied. In the example of FIG. 7, the temperature of the first main surface Wa of the substrate W increases after time t2. This is because no new drying liquid is supplied to the first main surface Wa of the substrate W after time t2. In other words, if the drying liquid, which is lower in temperature than the heat medium, is supplied to the first main surface Wa of the substrate W, the drying liquid cools the substrate W, but since the supply of the drying liquid has ended after time t2, the temperature of the substrate W increases. Therefore, the substrate temperature of the first main surface Wa of the substrate W during the evaporation time is higher than the substrate temperature of the first main surface Wa of the substrate W in the drying liquid supplying process.

[0102] Since the temperature of the first main surface Wa of the substrate W can be considered to be substantially equal to the temperature of the drying liquid on the first main surface Wa, the temperature of the drying liquid during the evaporation time is also higher than the temperature of the drying liquid during the drying liquid supplying step. Furthermore, the higher the temperature of the drying liquid, the lower the surface tension of the drying liquid. As described above, since the temperature of the drying liquid during the evaporation time is high, it is possible to reduce the surface tension of the drying liquid during the evaporation time. Moreover, it is also possible to improve the evaporation rate of the drying liquid.

[0103] The higher the surface tension of the drying liquid, the more likely the pattern collapses. Also, the lower the evaporation rate, the more likely the pattern collapses. This is because the lower the evaporation rate, the larger the impulse of the surface tension acting on the pattern. According to this embodiment, the evaporation rate can be improved while reducing the surface tension of the drying liquid, and therefore the rate of pattern collapse can be effectively reduced.

[0104] 7, at time t3, which is later than time t2, the control unit 90 switches the supply valve 42 from the open state to the closed state. As a result, the nozzle 4 stops discharging the heat medium at time t3. That is, the substrate heating unit 40 stops heating the second main surface Wb of the substrate W at time t3. Therefore, after time t3, the temperature of the first main surface Wa of the substrate W decreases over time.

[0105] In the above example, in the drying step (step S6), a high-temperature inert gas is supplied to the first main surface Wa of the substrate W. This can further increase the temperature of the drying liquid on the first main surface Wa of the substrate W, and further promote evaporation. This can further reduce the rate of pattern collapse. In addition, the temperature distribution of the drying liquid on the first main surface Wa of the substrate W can be made uniform.

[0106] In the above example, the substrate holder 2 increases the rotation speed of the substrate W in the drying step. This makes it possible to increase the amount of drying liquid that splashes outward from the periphery of the substrate W, while further promoting evaporation of the drying liquid. In other words, the evaporation of the drying liquid is promoted while the film of the drying liquid on the first main surface Wa is thinned by the splashing. This makes it possible to further reduce the collapse rate of the pattern.

[0107] In the above example, in the drying step, the movement driver 35i moves the shield plate 6 to a drying position closer to the first main surface Wa than the shielding process position. This makes it possible to narrow the gap between the shield plate 6 and the substrate W, and to increase the flow rate of the inert gas flowing outward in the radial direction from between the shield plate 6 and the substrate W. This makes it possible to suppress or prevent the heat medium from flowing around the periphery of the substrate W. This makes it possible to reduce the collapse rate of the pattern in the periphery of the first main surface Wa of the substrate W, and also to suppress the adhesion of particles to the periphery.

[0108] Conversely, in the drying liquid supplying step, the shielding plate 6 is stopped at the blocking processing position that is farther from the substrate W than the drying position. Therefore, even if the drying liquid discharged from the nozzle 3i bounces off the first main surface Wa of the substrate W, the possibility that the rebounded drying liquid will adhere to the lower surface of the shielding plate 6 can be reduced. If the drying liquid adheres to the lower surface of the shielding plate 6, for example, when the next substrate W is processed, droplets of the adhered drying liquid may fall onto the first main surface Wa of the substrate W. This is not preferable as it may cause processing problems. If the shielding plate 6 is stopped at the blocking processing position in the drying liquid supplying step as described above, the occurrence of such problems can be suppressed.

[0109] In the above example, the substrate heating section 40 heats the second main surface Wb of the substrate W in the drying liquid supplying step, and also heats the second main surface Wb of the substrate W during the transition from the drying liquid supplying step to the drying step. That is, the substrate heating section 40 continues to heat the second main surface Wb of the substrate W throughout the drying liquid supplying step and the early stage of the drying step. This makes it possible to maintain a higher temperature of the first main surface Wa of the substrate W at the start of the drying step (i.e., time t2). That is, it is possible to increase the temperature of the drying liquid from the start of the drying step. Therefore, the evaporation rate of the drying liquid can be increased more quickly in the drying step, and the pattern collapse rate can be more appropriately reduced.

[0110] Furthermore, in the drying liquid supplying step, the efficiency of replacing the rinsing liquid with the drying liquid can be improved by increasing the temperature of the drying liquid on the first main surface Wa of the substrate W. In other words, it is possible to suppress the residue of the rinsing liquid, which has a larger surface tension than the drying liquid. This makes it possible to further reduce the rate of pattern collapse in the drying step.

[0111] <Second embodiment> The configuration of the processing unit 1 according to the second embodiment is similar to that of the first embodiment, except for the specific configuration of the substrate heating section 40. FIG. 8 is a diagram that shows an example of the configuration of the substrate heating section 40 according to the second embodiment. In the example of FIG. 8, the substrate heating section 40 includes a nozzle 4, a common pipe 411, a first temperature pipe 412, a second temperature pipe 413, and a mixing section 45. The downstream end of the common pipe 411 is connected to the nozzle 4, and the upstream end of the common pipe 411 is connected to the mixing section 45. The downstream end of the first temperature pipe 412 and the downstream end of the second temperature pipe 413 are also connected to the mixing section 45. The upstream ends of the first temperature pipe 412 and the second temperature pipe 413 are connected to a heat medium supply source. A heat medium having a first medium temperature flows through the first temperature pipe 412, and a heat medium having a second medium temperature flows through the second temperature pipe 413. The second medium temperature is lower than the first medium temperature. Hereinafter, the heat medium at the first medium temperature flowing through the first temperature pipe 412 is also referred to as the high-temperature heat medium, and the heat medium at the second medium temperature flowing through the second temperature pipe 413 is also referred to as the low-temperature heat medium. In the example of FIG. 8, a heater 44 is provided in the first temperature pipe 412. The heater 44 heats the high-temperature heat medium flowing through the first temperature pipe 412 so that the temperature of the heat medium becomes the first medium temperature. The second medium temperature may be room temperature. Alternatively, a heater (not shown) may be provided in the second temperature pipe 413 to heat the low-temperature heat medium to the second medium temperature higher than room temperature.

[0112] The mixer 45 mixes the high-temperature heat medium from the first temperature pipe 412 and the low-temperature heat medium from the second temperature pipe 413 at a variable mixing ratio, and causes the mixed heat medium to flow into the common pipe 411. The mixing ratio of the mixer 45 is controlled by the control unit 90. In the example of FIG. 8, the mixer 45 includes a multiple valve 451, a flow rate control valve 452, and a flow rate control valve 453. The flow rate control valve 452 adjusts the flow rate of the high-temperature heat medium flowing through the first temperature pipe 412. The flow rate control valve 453 adjusts the flow rate of the low-temperature heat medium flowing through the second temperature pipe 413. The flow rate control valve 452 and the flow rate control valve 453 are controlled by the control unit 90. The control unit 90 adjusts each flow rate, thereby adjusting the mixing ratio. The multiple valve 451 switches between connection and disconnection between the common pipe 411 and the first temperature pipe 412, and switches between connection and disconnection between the common pipe 411 and the second temperature pipe 413. If multiple valve 451 itself has a function for adjusting the flow rate, flow rate adjustment valve 452 and flow rate adjustment valve 453 are not necessary.

[0113] 8, a supply valve 42 is provided in the common pipe 411. The supply valve 42 switches between opening and closing the common pipe 411. The supply valve 42 is controlled by the control unit 90.

[0114] <Operation example of substrate processing apparatus> The operation of the processing unit 1 according to the second embodiment is as shown in FIG. 4 referred to in the first embodiment. However, the specific operation of the substrate heating section 40 is different from that of the first embodiment. In the second embodiment, the substrate heating section 40 heats the substrate W in the drying step (step S6) with a second amount of heat per unit time that is greater than the first amount of heat per unit time in the drying liquid supply step (step S5). As a more specific example, the substrate heating section 40 supplies the substrate W in the drying step with a heat medium having a higher temperature than the heat medium supplied to the substrate W in the drying liquid supply step. Specifically, the substrate heating section 40 adjusts the mixture ratio of the high-temperature heat medium and the low-temperature heat medium, and supplies the heat medium having a higher temperature than the heat medium in the drying liquid supply step to the second main surface of the substrate W in the drying step.

[0115] 9 is a diagram showing an example of a timing chart of the processing unit 1 according to the second embodiment, and a schematic diagram showing an example of a change in the flow rate of the heat medium and the temperature of the heat medium over time. In the example of FIG. 9, an example of the flow rate of the high-temperature heat medium is shown in graph G1, and an example of the flow rate of the low-temperature heat medium is shown in graph G2.

[0116] 9, the flow rate of the high-temperature heat medium is constant from time t1 to time t3. On the other hand, the flow rate of the low-temperature heat medium decreases at time t2. In other words, the flow rate of the low-temperature heat medium during the evaporation time from time t2 to time t3 is smaller than the flow rate of the low-temperature heat medium during the drying liquid supplying step from time t1 to time t2. Therefore, the temperature of the heat medium discharged from the nozzle 4 during the evaporation time is higher than the temperature of the heat medium discharged from the nozzle 4 during the drying liquid supplying step.

[0117] In the second embodiment, the flow rates of the high-temperature heat medium and the low-temperature heat medium are not limited to those described above as long as the temperature of the heat medium discharged from the nozzle 4 is higher in the drying step (step S6) than in the drying liquid supplying step (step S5). In short, the ratio of the flow rate of the high-temperature heat medium to the flow rate of the low-temperature heat medium (=flow rate of high-temperature heat medium / flow rate of low-temperature heat medium) is higher in the drying step than in the drying liquid supplying step.

[0118] The temperature of the heat medium discharged from the nozzle 4 in the drying liquid supplying step may be adjusted to be less than the boiling point bp of the drying liquid. When the drying liquid is isopropyl alcohol, the boiling point bp of the drying liquid is about 82.4 degrees Celsius. In this case, the temperature of the heat medium in the drying liquid supplying step may be adjusted to be less than 82.4 degrees Celsius. As a specific example, the first medium temperature of the high-temperature heat medium is set to a value (e.g., 85 degrees Celsius) greater than the boiling point bp of the drying liquid, and the second medium temperature of the low-temperature heat medium is set to a value (e.g., room temperature) less than the boiling point pb of the drying liquid. Then, the mixer 45 mixes the high-temperature heat medium and the low-temperature heat medium at a mixing ratio such that the temperature of the heat medium is less than the boiling point bp of the drying liquid.

[0119] According to this, since the temperature of the heat medium discharged from the nozzle 4 is below the boiling point bp of the drying liquid, the drying liquid on the first main surface Wa of the substrate W is also below the boiling point bp. This makes it possible to more reliably suppress the boiling of the drying liquid on the first main surface Wa of the substrate W during the supply of the drying liquid. If the drying liquid on the first main surface Wa of the substrate W boils during the supply of the drying liquid, many particles will adhere to the first main surface Wa of the substrate W. In this embodiment, it is possible to more reliably suppress the adhesion of such particles.

[0120] On the other hand, in the drying process, the discharge of the drying liquid from the nozzle 3i is stopped. Therefore, even if the drying liquid on the first main surface Wa of the substrate W boils, it hardly causes adhesion of particles. Therefore, the substrate heating unit 40 may adjust the temperature of the heat medium during the evaporation time from time t2 to time t3 to be equal to or higher than the boiling point bp of the drying liquid. In other words, the mixer 45 may adopt a mixing ratio that makes the temperature of the heat medium equal to or higher than the boiling point bp of the drying liquid. In the example of FIG. 9, the flow rate of the low-temperature heat medium is set to zero.

[0121] The mixing unit 45 may gradually change the mixing ratio over time. For example, the mixing unit 45 may gradually change the mixing ratio during the time when the shielding plate 6 descends from the shielding processing position to the drying position.

[0122] As described above, in the second embodiment, the temperature of the heat medium in the drying step is higher than the temperature of the heat medium in the drying liquid supplying step. Therefore, the temperatures of the substrate W and the drying liquid in the drying step can be further increased. Therefore, the evaporation rate of the drying liquid in the drying step can be further improved. Therefore, the collapse rate of the pattern on the substrate W can be further reduced.

[0123] Conversely, the temperatures of the substrate W and the drying liquid in the drying liquid supplying step can be made lower than those in the drying step, which makes it possible to suppress or prevent the drying liquid from boiling on the first main surface Wa of the substrate W in the drying liquid supplying step, and thus makes it possible to suppress adhesion of particles to the first main surface Wa.

[0124] In the above example, the substrate heating unit 40 changes the temperature of the heat medium discharged from the nozzle 4 by changing the mixing ratio of the mixer 45. This allows the temperature of the heat medium to be changed quickly. Therefore, in the early stage of the drying process, the temperature of the heat medium can be increased more quickly, and the evaporation rate of the drying liquid can be increased more quickly. This also allows the pattern collapse rate to be further reduced.

[0125] <Third embodiment> In the first and second embodiments, the substrate heating unit 40 starts heating the second main surface Wb of the substrate W at approximately the same time as the nozzle 3i starts discharging the drying liquid in the drying liquid supplying step (step S5) (see FIGS. 7 and 9). However, this is not necessarily limited to this. The substrate heating unit 40 may start heating the second main surface Wb of the substrate W at a time later than the nozzle 3i starts discharging the drying liquid.

[0126] FIG. 10 is a diagram showing a timing chart of the processing unit 1 according to the third embodiment and an example of a temperature change of the first main surface Wa of the substrate W. In the example of FIG. 10, the control unit 90 switches the supply valve 32i from a closed state to an open state at time t1. As a result, the drying liquid starts to be discharged from the nozzle 3i toward the first main surface Wa of the substrate W. That is, the drying liquid supplying process substantially starts at time t1. On the other hand, in the example of FIG. 10, the control unit 90 switches the supply valve 42 from a closed state to an open state at time t12 after time t1. As a result, the high-temperature heat medium starts to be discharged from the nozzle 4 toward the second main surface Wb of the substrate W. That is, the substrate heating unit 40 starts to heat the second main surface Wb of the substrate W. Then, the control unit 90 switches the supply valve 32i from an open state to a closed state at time t2 after time t12. That is, the drying liquid supplying process substantially ends at time t2.

[0127] In short, during the drying liquid supply time T from time t1 to time t2, the substrate heating unit 40 does not heat the second main surface Wb of the substrate W during a predetermined pre-time T1 from time t1 to time t12, and heats the second main surface Wb of the substrate W during a predetermined post-time T2 from time t12 to time t2. The drying liquid supply time T is set to, for example, 20 seconds or more, and may be set to about 40 seconds as a specific example. The post-time T2 is set in advance to a time at which the temperature of the first main surface Wa of the substrate W at time t2 sufficiently approaches the boiling point of the drying liquid. For example, the post-time T2 may be set to half or less of the drying liquid supply time T, or may be set to one-third or less, one-quarter or less, or one-tenth or less of the drying liquid supply time T.

[0128] As described above, in the third embodiment, the substrate heating section 40 does not heat the substrate W during the previous time T1, and heats the second main surface Wb of the substrate W during the later time T2. That is, the substrate heating section 40 heats the second main surface Wb of the substrate W only during the later time T2. This makes it possible to shorten the operation time of the substrate heating section 40, and reduce the power consumption of the substrate processing apparatus 100. Furthermore, when the substrate heating section 40 supplies a high-temperature heat medium to the second main surface Wb of the substrate W, the amount of heat medium supplied can be reduced. When the heat medium is liquid, liquefaction can be reduced.

[0129] <Fourth embodiment> The configuration of the processing unit 1 according to the fourth embodiment is, for example, similar to that of the second embodiment. In the fourth embodiment, in the drying liquid supplying step (step S5), the substrate heating part 40 sets the temperature of the heat medium to the boiling point bp of the drying liquid or higher.

[0130] FIG. 11 is a diagram showing an example of a timing chart of the processing unit 1 according to the fourth embodiment, and a schematic diagram showing an example of a time change of the flow rate of the heat medium, the temperature of the heat medium, and the temperature of the first main surface Wa of the substrate W. In the example of FIG. 11, in the drying liquid supplying step (step S5), the temperature of the heat medium discharged from the nozzle 4 is higher than the boiling point bp of the drying liquid. When the drying liquid is isopropyl alcohol, the boiling point bp is 82.4 degrees Celsius, and the temperature of the heat medium is set to, for example, about 85 degrees Celsius. However, the temperature of the heat medium may be set to less than the boiling point of the heat medium. For example, when the heat medium is water, it may be set to less than 90 degrees Celsius, which is 10 degrees lower than the boiling point (100 degrees Celsius). This makes it possible to comply with the SEMI standard.

[0131] In the drying liquid supplying step, the drying liquid having a lower temperature than the heat medium is discharged from the nozzle 3i. The low-temperature drying liquid that continuously lands on the first main surface Wa of the substrate W can cool the first main surface Wa of the substrate W. The cooling capacity of the drying liquid increases as the flow rate of the drying liquid increases. Therefore, the flow rate adjustment valve 33i adjusts the flow rate of the drying liquid to a value at which the substrate temperature of the first main surface Wa of the substrate W is lower than the boiling point bp. Specifically, the flow rate of the drying liquid is preset to, for example, about 250 ml / min or more. In the example of FIG. 11, the temperature of the center of the first main surface Wa of the substrate W is shown as the substrate temperature. Since the high-temperature heat medium lands on the center of the second main surface Wb of the substrate W, the substrate temperature of the substrate W has a temperature distribution described below. That is, the substrate temperature is high at the center of the substrate W and decreases toward the radial outside. For this reason, in the example of FIG. 11, the highest value in the temperature distribution of the first main surface Wa of the substrate W is shown as the substrate temperature.

[0132] 11, the substrate temperature in the drying liquid supplying step is lower than the boiling point bp of the drying liquid. When the drying liquid is isopropyl alcohol, the highest substrate temperature in the temperature distribution of the substrate W can be adjusted to, for example, about 80 degrees Celsius or lower. This makes it possible to more reliably suppress boiling of the drying liquid in the drying liquid supplying step. In turn, it makes it possible to more reliably suppress adhesion of particles to the first main surface Wa of the substrate W.

[0133] Moreover, in the fourth embodiment, the temperature of the heat medium in the drying liquid supplying step is equal to or higher than the boiling point bp. Therefore, in the drying liquid supplying step, the maximum value in the temperature distribution on the first main surface Wa of the substrate W can be brought closer to the boiling point bp. The minimum value in the temperature distribution on the first main surface Wa of the substrate W in the drying liquid supplying step (i.e., the substrate temperature at the peripheral portion of the first main surface Wa) is, for example, 60 degrees Celsius or higher. In other words, the flow rate of the drying liquid can be set so that the substrate temperature on the first main surface Wa of the substrate W is 60 degrees Celsius or higher and lower than the boiling point bp of the drying liquid.

[0134] In the fourth embodiment, even during the transition from the drying liquid supplying process to the drying process, the nozzle 4 discharges the heat medium having a boiling point bp or higher onto the second main surface Wb of the substrate W. As a result, at the start of the drying process (i.e., time t2), the substrate temperature of the second main surface Wb of the substrate W can be made to a value closer to the boiling point bp of the drying liquid. This makes it possible to further increase the temperature of the drying liquid at the start of the drying process. In other words, the surface tension of the drying liquid can be quickly reduced while the evaporation rate of the drying liquid can be quickly increased.

[0135] During the evaporation time in the drying step, the substrate temperature of at least a part (for example, the center) of the first main surface Wa of the substrate W may be equal to or higher than the boiling point bp of the drying liquid. In the example of FIG. 11, the substrate temperature (maximum value) during the evaporation time is higher than the boiling point bp. That is, the temperature and flow rate of the heat medium are set so that the substrate temperature (maximum value) is equal to or higher than the boiling point bp. This makes it possible to further reduce the surface tension of the drying liquid while further increasing the evaporation rate of the drying liquid. Since the substrate temperature decreases toward the periphery side, the temperature of at least the periphery of the main surface of the substrate W is lower than the boiling point bp of the drying liquid. The drying liquid mainly flows outward on the first main surface Wa of the substrate W. That is, the drying liquid mainly flows in a state of contact with the first main surface Wa of the substrate W, rather than flowing in a state of floating from the first main surface Wa of the substrate W.

[0136] In the first to third embodiments, the substrate temperature of at least a part (e.g., the central part) of the first main surface Wa of the substrate W during the evaporation time may be equal to or higher than the boiling point bp of the drying liquid. In other words, in the first to third embodiments, the temperature and flow rate of the heat medium may be set so that the substrate temperature (maximum value) during the evaporation time is equal to or higher than the boiling point bp.

[0137] <Fifth embodiment> In the above example, the processing unit 1 performs the chemical step (step S3), the rinsing step (step S4), the drying liquid supply step (step S5), and the drying step (step S6) in this order, but this is not necessarily limited to this.

[0138] Fig. 12 is a flowchart showing a first example of the operation of the processing unit 1 according to the fifth embodiment. In the example of Fig. 12, the control unit 90 causes the processing unit 1 to execute processes from step S11 to step S19 according to a preset processing procedure (recipe). Steps S11 to S15 are similar to steps S1 to S5, respectively. However, in step S15 (drying liquid supplying step), the substrate heating unit 40 does not have to heat the substrate W.

[0139] Next, the processing unit 1 hydrophobicizes the first main surface Wa of the substrate W (corresponding to step S16: hydrophobization process: liquid supply process). Specifically, the processing unit 1 includes a nozzle that ejects a hydrophobization liquid, and ejects the hydrophobization liquid from the nozzle onto the first main surface Wa of the substrate W during rotation. The hydrophobization liquid includes, for example, a silicon-based hydrophobization liquid. The silicon-based hydrophobization liquid is a hydrophobization liquid that hydrophobicizes silicon (Si) itself and compounds containing silicon. The hydrophobization liquid is, for example, a silylation liquid that includes a liquid silylation agent (also called a silane coupling agent). When the first main surface Wa of the substrate W has been sufficiently hydrophobized, the processing unit 1 stops ejecting the hydrophobization liquid from the nozzle.

[0140] Next, the processing unit 1 executes steps S17 to S19, which are similar to steps S5 to S7, respectively.

[0141] As described above, in the first example, the drying step (step S18) is performed in the same manner as the drying step (step S6) in the first to fourth embodiments. This makes it possible to reduce the collapse rate of the pattern on the substrate W. Moreover, since the first main surface Wa of the substrate W is hydrophobized, the contact angle of the first main surface Wa can be reduced. This makes it possible to reduce the surface tension acting on the pattern, and further reduce the collapse rate of the pattern.

[0142] FIG. 13 is a flowchart showing a second example of the operation of the processing unit 1 according to the fifth embodiment. In the example of FIG. 13, the control unit 90 causes the processing unit 1 to execute the processes from step S21 to step S26 according to a preset processing procedure (recipe). Steps S21 to S26 are the same as steps S1 to S3 and steps S5 to S7, respectively. However, at the end of step S23 (chemical liquid process: corresponding to liquid supplying process), metal is exposed on the first main surface Wa of the substrate W. According to the second example, step S24 (drying liquid supplying process) is performed after step S23. Therefore, water is not supplied to the first main surface Wa of the substrate W. Therefore, it is possible to avoid a reaction between metal and water, and to avoid a defect caused by the reaction. Also, in the above-mentioned second example, a drying process (step S25) is performed similarly to the drying process (step S6) in the first to fourth embodiments. Therefore, it is possible to reduce the collapse rate of the pattern on the substrate W.

[0143] Sixth embodiment An example of the configuration of the substrate processing apparatus 100 according to the sixth embodiment is similar to that of the substrate processing apparatus 100 according to the first to fifth embodiments. However, a specific example of the blocking plate 6 differs from that of the blocking plate 6 according to the first to fifth embodiments. Fig. 14 is a diagram illustrating a first example of the configuration of the blocking plate 6 according to the sixth embodiment. Hereinafter, the lower surface of the blocking plate 6 is referred to as the lower surface 6a. A lower end opening (i.e., a gas discharge port) of the gas flow path 3g is formed in the center of the lower surface 6a of the blocking plate 6.

[0144] As shown in FIG. 14, the gas flow passage 3g has a vertical flow passage 3ga and an expanded diameter flow passage 3gb. The vertical flow passage 3ga is located vertically above the expanded diameter flow passage 3gb and extends along the vertical direction. In the example of FIG. 14, the inner peripheral surface of the hollow shaft 61 forms the outer peripheral surface of the vertical flow passage 3ga. That is, the vertical flow passage 3ga is located inside the hollow shaft 61. In the example of FIG. 14, the lower end opening (i.e., the discharge port) of the nozzle 3i is located above the lower end of the vertical flow passage 3ga. Above the lower end opening of the nozzle 3i, the vertical flow passage 3ga corresponds to a cylindrical space between the inner peripheral surface of the hollow shaft 61 and the outer peripheral surface of the nozzle 3i. Below the lower end opening of the nozzle 3i, the vertical flow passage 3ga corresponds to a columnar space surrounded by the inner peripheral surface of the hollow shaft 61.

[0145] The lower end of the vertical flow passage 3ga is connected to the upper end of the expanded diameter flow passage 3gb. The size of the lower end opening of the expanded diameter flow passage 3gb (i.e., the lower end opening of the gas flow passage 3g) in a plan view is larger than the size of the vertical flow passage 3ga in a plan view. Here, as an example, the inner circumferential surface of the hollow shaft 61 has a shape that follows the side surface of a cylinder, and the lower end opening of the expanded diameter flow passage 3gb has a circular shape. In this case, the diameter (outer diameter) R2 of the vertical flow passage 3ga is smaller than the diameter R1 of the lower end opening of the expanded diameter flow passage 3gb.

[0146] In the example of Fig. 14, the diameter of the expanding diameter flow passage 3gb becomes wider as it approaches the gas discharge port. The expanding diameter flow passage 3gb is formed by the inner peripheral surface of the blocking plate 6, which is an inclined surface. The inner peripheral surface of the blocking plate 6 has a shape that follows the side surface of a truncated cone, for example, and its lower end periphery is connected to the lower surface 6a of the blocking plate 6. The lower end periphery forms the lower end port of the expanding diameter flow passage 3gb (i.e., the gas discharge port).

[0147] 14, the diameter of the expanded diameter flow passage 3gb may increase monotonically as it approaches the lower surface 6a of the blocking plate 6. Alternatively, the diameter of the expanded diameter flow passage 3gb may increase stepwise (i.e., in a stepped manner) as it approaches the lower surface 6a of the blocking plate 6.

[0148] According to the sixth embodiment, the inert gas is also discharged from the lower end opening of the gas flow path 3g toward the first main surface Wa of the substrate W. Fig. 15 is a diagram showing an example of how the inert gas is discharged. When the inert gas is discharged toward the first main surface Wa of the substrate W, the inert gas collides with the liquid film of the drying liquid on the first main surface Wa of the substrate W. This collision may cause the drying liquid to splash. In the sixth embodiment, the lower end opening of the gas flow path 3g is large, so that the splashed drying liquid is unlikely to reach the lower surface 6a of the shielding plate 6.

[0149] A specific example of the operation of the processing unit 1 in the sixth embodiment may be similar to or different from the operations of the processing unit 1 in the first to fifth embodiments. As an example, the processing unit 1 in the sixth embodiment operates according to the flowchart in FIG.

[0150] FIG. 16 is a diagram showing a first example of a timing chart of the processing unit 1 according to the sixth embodiment. In the example of FIG. 16, an example of the change in the position of the blocking plate 6 over time and the change in the flow rate of the inert gas over time is shown. In the example of FIG. 16, similarly to the first to fifth embodiments, the movement drive unit 35i moves the blocking plate 6 from the blocking processing position P1 to the drying position P2 when stopping the supply of the drying liquid (time t2). In the sixth embodiment, the gas flow path 3g of the blocking plate 6 has an expanded diameter flow path 3gb. Therefore, as described above, even if the blocking plate 6 is moved to a position closer to the first main surface Wa of the substrate W, the adhesion of the drying liquid to the blocking plate 6 can be suppressed. For example, the drying position may be set to a position where the distance between the lower surface 6a of the blocking plate 6 and the first main surface Wa of the substrate W is 2 mm or less, or may be set to a position where the distance is 1 mm or less.

[0151] By narrowing the gap, the processing unit 1 can dry the substrate W more quickly. In other words, since the gap can be set narrow from the early stage of the drying process, the processing unit 1 can dry the substrate W with high drying performance from the early stage of the drying process. In particular, the drying performance in the early stage of the drying process has a strong influence on suppressing pattern collapse. Therefore, the processing unit 1 can further reduce the rate of pattern collapse.

[0152] 16, the processing unit 1 may supply an inert gas to the first main surface Wa of the substrate W in the drying liquid supplying step (step S5). That is, the control unit 90 may open the supply valve 32g in the drying liquid supplying step. This allows the inert gas to be discharged from the lower end opening of the gas flow path 3g also in the drying liquid supplying step. This makes it possible to prevent the volatile components of the drying liquid from remaining in the space between the shielding plate 6 and the substrate W. The flow rate of the inert gas in the drying liquid supplying step is set to, for example, 20 mL (milliliters) / min or less.

[0153] In the example of FIG. 16, the processing unit 1 increases the flow rate of the inert gas when moving the shield plate 6 to the drying position P2 in the drying process. For example, the flow rate adjustment valve 33g may increase the flow rate of the inert gas from a value of 20 mL (milliliters) / min or less to a value of 30 mL / min or more. In the example of FIG. 16, the flow rate adjustment valve 33g increases the flow rate of the inert gas stepwise over time. The flow rate adjustment valve 33g may increase the flow rate to 100 mL / min or more as the final flow rate of the inert gas in the drying process. The processing unit 1 may increase the flow rate to 150 mL / min or more, or may increase the flow rate to 200 mL / min or more.

[0154] As described above, the processing unit 1 increases the flow rate of the inert gas as the shield plate 6 descends to the drying position P2. Therefore, the processing unit 1 can dry the substrate W with high drying performance from the early stage of the drying process. Moreover, in the sixth embodiment, since the gas flow path 3g has the expanded diameter flow path 3gb, even if the flow rate of the inert gas is increased and liquid splashing becomes more likely to occur, the liquid splashing is less likely to reach the shield plate 6. Therefore, adhesion of the drying liquid to the shield plate 6 can also be suppressed.

[0155] The flow rate control valve 33g may increase the flow rate of the inert gas in a stepwise manner, rather than stepwise. In other words, the flow rate control valve 33g may increase the flow rate of the inert gas to the final value at time t2. Even if the inert gas is supplied at a high flow rate from the beginning of the drying process in this way, the gas flow path 3g has the expanded diameter flow path 3gb, so that the liquid splash is unlikely to reach the blocking plate 6. If the processing unit 1 supplies the inert gas at a high flow rate from the beginning of the drying process, the drying performance can be further improved. Therefore, the processing unit 1 can further reduce the collapse rate of the pattern.

[0156] FIG. 17 is a diagram showing a second example of a timing chart of the processing unit 1 according to the sixth embodiment. In the example of FIG. 17, at time t11 in the middle of the drying liquid supplying process, the control unit 90 causes the movement drive unit 35i to lower the blocking plate 6. Specifically, in the example of FIG. 17, the blocking plate 6 is located at the first blocking processing position P11 at the beginning of the drying liquid supplying process. Then, at time t11, the movement drive unit 35i moves the blocking plate 6 from the first blocking processing position P11 to the second blocking processing position P12. The second blocking processing position P12 is closer to the first main surface Wa of the substrate W than the first blocking processing position P11, and is farther from the first main surface Wa of the substrate W than the drying position P2 (first drying position P21 in the figure). That is, the second blocking processing position P12 is a position between the first blocking processing position P11 and the drying position P2. Each of the first blocking processing position P11 and the second blocking processing position P12 is an example of the blocking processing position P1. The second blocking processing position P12 may be set at a position where the distance between the blocking plate 6 and the substrate W is 10 mm or less, or may be set at a position where the distance is about 5 mm, for example. The first blocking processing position P11 may be set at a position where the distance between the blocking plate 6 and the substrate W is 20 mm or more (for example, about 30 mm).

[0157] As described above, in the example of Figure 17, in the drying liquid supply process, the processing unit 1 supplies drying liquid to the first main surface Wa of the substrate W with the blocking plate 6 positioned at the first blocking processing position P11, and then moves the blocking plate 6 to the second blocking processing position P12 while supplying the drying liquid.

[0158] Here, a case where the gas flow path 3g extends in a cylindrical shape will be described. FIG. 18 is a diagram showing an example of the state of the processing unit 1 in the drying liquid supplying step. Here, the blocking plate 6 is located at the second blocking processing position P12. In the example of FIG. 18, the outlet portion of the gas flow path 3g below the outlet of the nozzle 3i extends vertically with equal width. In the outlet portion, the inert gas flows through the space between the liquid column of the drying liquid from the outlet of the nozzle 3i and the inner peripheral surface of the blocking plate 6, and then flows through the space between the lower surface 6a of the blocking plate 6 and the first main surface Wa of the substrate W. Since the outlet portion of the gas flow path 3g extends vertically with equal width, the volume of the space is relatively small. In addition, when the blocking plate 6 is located at the second blocking processing position P12, the volume of the space between the blocking plate 6 and the substrate W is also relatively small. Therefore, the flow path cross section of the inert gas is small. Therefore, the pressure of the inert gas increases, and the liquid column of the drying liquid is easily affected by the flow of the inert gas. As a result, the column of drying liquid may fluctuate. In Fig. 18, the fluctuating liquid column of drying liquid is shown typically by a wavy line. Such fluctuation of the drying liquid may cause the landing position on the first main surface Wa of the substrate W to fluctuate, or droplets may fly off from the column of drying liquid and adhere to the shield plate 6.

[0159] Fig. 19 is a diagram showing an example of the state of the processing unit 1 in the drying liquid supplying step according to the sixth embodiment. In the example of Fig. 19, the gas flow path 3g has an expanded diameter flow path 3gb. Therefore, the volume of the space between the liquid column of drying liquid from the nozzle 3i and the inner circumferential surface of the blocking plate 6 is relatively large. Therefore, the inert gas can flow at a position relatively far away from the liquid column of drying liquid, and the influence of the flow of the inert gas on the drying liquid can be reduced. Therefore, the fluctuation of the liquid column of drying liquid can be reduced.

[0160] In the above example, in the final period of the drying liquid supplying step (step S5), the blocking plate 6 is located at the second blocking process position P12, which is closer to the drying position P2. Therefore, in the subsequent drying step (step S6), the movement distance of the blocking plate 6 can be shortened. That is, in the early stage of the drying step, the blocking plate 6 only needs to move from the second blocking process position P12 to the drying position P2, and can reach the drying position P2 in a shorter movement distance than the movement distance from the first blocking process position P11 to the drying position P2. Therefore, the movement drive unit 35i can make the blocking plate 6 reach the drying position P2 at an earlier timing. Therefore, the drying performance in the early stage of the drying step can be further improved.

[0161] Note that time t11 when the blocking plate 6 starts to move toward the second blocking process position P12 may be later than the center time of the drying liquid supply time during which the drying liquid is supplied. In other words, the time difference between time t11 and time t2 may be shorter than the time difference between time t1 and time t11.

[0162] In the example of FIG. 17, at time t21 during the drying process, the control unit 90 causes the movement drive unit 35i to move the shield plate 6 from the first drying position P21 to the second drying position P22. The second drying position P22 is closer to the first main surface Wa of the substrate W than the first drying position P21. The second drying position P22 may be a position that is 0.5 mm or less away from the first main surface Wa of the substrate W. Each of the first drying position P21 and the second drying position P22 is an example of the drying position P2. The time t21 at which the shield plate 6 starts to move to the second drying position P22 may be, for example, after the time at which the scattering of the drying liquid from the periphery of the substrate W has substantially ended. That is, the shield plate 6 descends to the second drying position P22 after the drying liquid above the pattern of the substrate W has substantially been shaken off to the outside. Thereby, the drying liquid in the pattern of the substrate W can be evaporated while the shield plate 6 is positioned at the second drying position P22, and the substrate W can be dried more quickly. The control unit 90 may cause the movement drive unit 35i to move the shielding plate 6 to the second drying position P22 when a preset time has elapsed from time t2. The time is set to a time sufficient for the scattering of the drying liquid from the substrate W to substantially finish.

[0163] FIG. 20 is a diagram showing a second example of the configuration of the blocking plate 6 according to the sixth embodiment. In the second example, a gas nozzle 3gA is provided. The gas nozzle 3gA is provided inside the hollow shaft 61, similar to the nozzle 3i. The gas nozzles 3gA are adjacent to each other in the horizontal direction. The gas nozzles 3gA extend in the vertical direction, and their lower end openings function as gas discharge ports. The upstream end of the gas nozzle 3gA is connected to the downstream end of a supply pipe 31gA. The upstream end of the supply pipe 31gA is connected to a gas supply source.

[0164] The supply pipe 31gA is provided with a supply valve 32gA, a flow rate adjustment valve 33gA, and a heater 34gA. The supply valve 32gA switches the supply pipe 31gA between open and closed. The flow rate adjustment valve 33gA adjusts the flow rate of the inert gas flowing through the supply pipe 31gA. The heater 34gA heats the inert gas flowing through the supply pipe 31gA. The heater 34gA may be, for example, an electric resistance type heater having an electric heating wire. The supply valve 32gA, the flow rate adjustment valve 33gA, and the heater 34gA are controlled by the control unit 90.

[0165] In the drying liquid supplying step (step S5), the control unit 90 may open the supply valve 32g and close the supply valve 32gA. As a result, in the drying liquid supplying step, the inert gas is not discharged from the gas nozzle 3gA, but is discharged from the gas flow path 3g. Since the inert gas is not discharged from the gas nozzle 3gA provided at a position close to the nozzle 3i, it is possible to suppress fluctuation of the liquid column of the drying liquid caused by the inert gas. On the other hand, in the drying step (step S6), the control unit 90 opens the supply valve 32g and the supply valve 32gA. As a result, in the drying step, the inert gas is discharged from the gas flow path 3g and the gas nozzle 3gA. Therefore, the inert gas can be more appropriately supplied to the center of the substrate W. The flow rate value of the inert gas described above may be the sum of the flow rates of the inert gas flowing through the gas flow path 3g and the gas nozzle 3gA.

[0166] As described above, the substrate processing apparatus 100 and the substrate processing method have been described in detail, but the above description is merely an example in all respects, and this disclosure is not limited thereto. In addition, the above-mentioned various modified examples can be combined and applied as long as they are not mutually inconsistent. It is understood that many modified examples not exemplified can be envisioned without departing from the scope of this disclosure.

[0167] In the above example, a dedicated nozzle is provided for each fluid, but one nozzle may be shared by different types of fluid.

[0168] In the above example, the substrate heating section 40 supplies a heat medium to the second main surface Wb of the substrate W, but this is not necessarily limited to this. The substrate heating section 40 may include, for example, a heater provided at a position vertically facing the second main surface Wb of the substrate W. The heater may be, for example, an electric resistance heater including an electric heating wire, or an optical heater that outputs light for heating.

[0169] In the above example, the substrate heating unit 40 heats the second main surface Wb of the substrate W during the evaporation time from time t2 when the supply of the drying liquid is stopped to time t3. However, the substrate heating unit 40 may interrupt heating during a part of the evaporation time. [Explanation of symbols]

[0170] 3g Gas flow path 3gb expanded diameter channel 6. Barrier P1 Cut-off position P11 First cut-off position P12 Second cut-off position P2 drying position P21 1st drying position P22 2nd drying position S1, S11, S21 Holding process (step) S4, S16, S23 Liquid supply process (step) S5, S17, S24 Drying liquid supply process (step) S6, S18, S25 Drying process (step) Time after T2 W substrate Wa First main surface Wb 2nd principal surface

Claims

1. a holding step of holding a substrate having a first main surface on which a pattern is formed and a second main surface opposite to the first main surface; a liquid supplying step of supplying a processing liquid to the first main surface of the substrate; a drying liquid supplying step of supplying a drying liquid to the first main surface of the substrate after the liquid supplying step; a drying step of heating the second main surface of the substrate for a predetermined period of time after the drying liquid supplying step to make the substrate temperature of the first main surface of the substrate equal to or higher than the substrate temperature in the drying liquid supplying step, thereby drying the substrate; A substrate processing method comprising:

2. 2. The substrate processing method according to claim 1, the substrate temperature of at least a part of the first main surface of the substrate is set to a boiling point of the drying liquid or higher during the predetermined period.

3. 3. The substrate processing method according to claim 1, further comprising the steps of: In the drying liquid supplying step, the second main surface of the substrate is heated with a first heat amount per unit time; the second main surface of the substrate is heated with a second amount of heat per unit time greater than the first amount of heat during the predetermined period of the drying step.

4. 3. The substrate processing method according to claim 1, further comprising the steps of: a heat medium is supplied to the second main surface of the substrate during the predetermined period.

5. 4. The substrate processing method according to claim 3, In the drying liquid supplying step, a heat medium obtained by mixing a high-temperature heat medium and a low-temperature heat medium having a lower temperature than the high-temperature heat medium is supplied to the second main surface of the substrate; a mixing ratio of the high-temperature heat medium and the low-temperature heat medium is adjusted, and the heat medium having a higher temperature than the heat medium in the drying liquid supplying step is supplied to the second main surface of the substrate for at least the predetermined period of the drying step.

6. 5. The substrate processing method according to claim 4, further comprising the steps of: the heat medium having a temperature equal to or higher than a boiling point of the drying liquid is supplied to the second main surface of the substrate during the predetermined period.

7. 5. The substrate processing method according to claim 4, further comprising the steps of: a drying liquid supply step of supplying the heat medium having a temperature equal to or higher than a boiling point of the drying liquid to the second main surface of the substrate while supplying the drying liquid at a flow rate such that the substrate temperature of the first main surface of the substrate is lower than the boiling point.

8. 5. The substrate processing method according to claim 4, further comprising the steps of: The heat transfer medium includes a liquid. In the drying liquid supplying step, the drying liquid is supplied to the first main surface of the substrate in a state where a blocking plate having an opposing surface facing the first main surface of the substrate is positioned at a blocking processing position; A substrate processing method, comprising: during the specified period of the drying process, supplying an inert gas toward the first main surface of the substrate from a gas outlet in a center of the blocking plate while the blocking plate is moved to a drying position closer to the first main surface than the blocking processing position.

9. 9. The substrate processing method according to claim 8, further comprising the steps of: the heated inert gas is supplied to the first main surface of the substrate during the predetermined period.

10. 9. The substrate processing method according to claim 8, further comprising the steps of: In the drying liquid supplying step, the inert gas is supplied to the first main surface of the substrate through a gas flow path inside the blocking plate, the gas flow path having a diameter increasing toward the gas ejection port, The substrate processing method includes increasing a flow rate of the inert gas while moving the blocking plate from the blocking processing position to the drying position.

11. 11. The substrate processing method according to claim 10, A substrate processing method in which, in the drying liquid supplying process, the drying liquid is supplied to the first main surface of the substrate while the blocking plate is positioned at a first blocking processing position, which is one of the blocking processing positions, and then, while supplying the drying liquid, the blocking plate is moved to a second blocking processing position, which is one of the blocking processing positions and is closer to the first main surface of the substrate than the first blocking processing position.

12. 3. The substrate processing method according to claim 1, further comprising the steps of: The substrate is rotated at a rotation speed higher than a rotation speed of the substrate in the drying liquid supplying step during the predetermined period of the drying step.

13. 3. The substrate processing method according to claim 1, further comprising the steps of: a drying liquid supplying step of supplying the drying liquid to the second main surface of the substrate, the second main surface being heated only during a latter period of a drying liquid supplying time during which the drying liquid is supplied.

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