Substrate processing method

Abstract

The present invention provides a technique with which it is possible to effectively reduced the probability of collapse of a substrate pattern. This substrate processing method includes a holding step, a fluid supplying step, a first-drying-fluid supplying step, a second-drying-fluid supplying step, and a drying step. In the first-drying-fluid supplying step, a first drying-fluid having a first boiling point (bp1) and having a lower surface tension than a treatment fluid is supplied to a first main surface of a substrate. In the second-drying-fluid supplying step, a second drying-fluid having a second boiling point (bp2) and having a lower surface tension than the first drying-fluid is supplied to the first main surface of the substrate. In the drying step, the substrate is dried. During at least part of the amount of time of the first-drying-fluid supplying step, a second main surface of the substrate is heated to a first temperature, and during at least part of the amount of time of the second-drying-fluid supplying step, at least a partial section of the second main surface of the substrate is heated to a second temperature. Subtracting the second temperature from the first temperature results in a positive or negative value, and the sign of such value will be the same as the sign of the positive or negative value obtained as a result of subtracting the second boiling point (bp2) from the first boiling point (bp1).

Description

Substrate processing method

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

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

[0003] JP 2015-23182 A

[0004] However, in the technology described in Patent Document 1, the substrate is dried by evaporating isopropyl alcohol. In recent years, as patterns have become finer, patterns on substrates have become more prone to collapse, and it is difficult to sufficiently reduce the rate of pattern collapse by simply evaporating isopropyl alcohol.

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

[0006] A first aspect is a substrate processing method, the method including: 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 first drying liquid supplying step of supplying, after the liquid supplying step, a first drying liquid to the first main surface of the substrate, the first drying liquid having a first boiling point and a surface tension lower than that of the processing liquid; and a second drying liquid to the first main surface of the substrate, the second drying liquid having a second boiling point different from the first boiling point and a surface tension lower than that of the first drying liquid, after the first drying liquid supplying step. and a drying step of drying the substrate after the second drying liquid supplying step, wherein the second main surface of the substrate is heated to a first temperature during at least a portion of the time in the first drying liquid supplying step, and at least a portion of the second main surface of the substrate is heated to a second temperature different from the first temperature during at least a portion of the time in the second drying liquid supplying step, and the sign of the value obtained by subtracting the second temperature from the first temperature is the same as the sign of the value obtained by subtracting the second boiling point from the first boiling point.

[0007] A second aspect is a substrate processing method according to the first aspect, wherein in the first drying liquid supply step, a heat medium at a first medium temperature is supplied to the second main surface of the substrate, and in the second drying liquid supply step, the heat medium at a second medium temperature is supplied to the second main surface of the substrate, and the positive and negative signs of the value obtained by subtracting the second medium temperature from the first medium temperature are the same as the positive and negative signs of the value obtained by subtracting the second boiling point from the first boiling point.

[0008] A third aspect is the substrate processing method according to the first or second aspect, wherein the higher of the first temperature and the second temperature is equal to or higher than the lower of the first boiling point and the second boiling point.

[0009] A fourth aspect is a substrate processing method according to any one of the first to third aspects, wherein miscibility between the processing liquid and the first drying liquid is higher than miscibility between the processing liquid and the second drying liquid.

[0010] A fifth aspect is a substrate processing method according to any one of the first to fourth aspects, wherein in the first drying liquid supply step, the first drying liquid is supplied to the first main surface of the substrate at a flow rate such that the temperature of the first main surface of the substrate is lower than the first boiling point of the first drying liquid, while at least a portion of the second main surface of the substrate is heated to a temperature equal to or higher than the first boiling point of the first drying liquid.

[0011] A sixth aspect is a substrate processing method according to any one of the first to fifth aspects, wherein in the second drying liquid supplying step, the second drying liquid is supplied to the first main surface of the substrate at a flow rate such that the temperature of the first main surface of the substrate is lower than the second boiling point of the second drying liquid, while at least a portion of the second main surface of the substrate is heated to a temperature equal to or higher than the second boiling point of the second drying liquid.

[0012] A seventh aspect is a substrate processing method according to any one of the first to sixth aspects, wherein the second temperature is higher than the first temperature, and in the second drying liquid supply step, during a first period of a second drying liquid supply time during which the second drying liquid is supplied, the temperature of the second main surface of the substrate is lower than the second temperature, and during a second period of the second drying liquid supply time, the second main surface of the substrate is heated to the second temperature.

[0013] According to the first aspect, when the second boiling point is higher than the first boiling point, the second temperature is higher than the first temperature. Therefore, in the second drying liquid supplying step, the temperature of the second drying liquid on the first main surface of the substrate can be increased. Therefore, the first drying liquid can be replaced with the second drying liquid on the first main surface of the substrate with higher replacement efficiency. Therefore, at the end of the second drying liquid supplying step, the amount of the remaining first drying liquid, which has a higher surface tension, can be reduced. Therefore, the rate of pattern collapse during drying can be reduced. Furthermore, because the temperature of the second drying liquid is high at the end of the second drying liquid supplying step, the second drying liquid can evaporate with a lower surface tension and at a higher evaporation rate. This also reduces the rate of pattern collapse.

[0014] When the first boiling point is higher than the second boiling point, the first temperature is higher than the second temperature. Therefore, in the first drying liquid supplying step, the temperature of the first drying liquid on the first main surface of the substrate can be increased. Therefore, the treatment liquid can be replaced with the first drying liquid on the first main surface of the substrate with higher replacement efficiency. Therefore, at the end of the first drying liquid supplying step, the amount of remaining treatment liquid with a higher surface tension can be reduced. Therefore, the rate of pattern collapse during drying can be reduced.

[0015] According to the second aspect, with a simple configuration, the second main surface of the substrate can be heated to a first temperature corresponding to the first boiling point of the first drying liquid and a second temperature corresponding to the second boiling point of the second drying liquid.

[0016] According to the third aspect, when the second boiling point is higher than the first boiling point, the second main surface of the substrate is heated to a second temperature higher than the first boiling point of the first drying liquid during at least a portion of the second drying liquid supplying step, thereby increasing the temperature of the second drying liquid on the first main surface of the substrate and thereby enabling the first drying liquid to be replaced with the second drying liquid with higher replacement efficiency.

[0017] According to the fourth aspect, the treatment liquid can be replaced with the first drying liquid and the first drying liquid can be replaced with the second drying liquid with higher replacement efficiency.

[0018] According to the fifth aspect, in the first drying liquid supplying step, the first drying liquid is supplied at a flow rate such that the temperature of the first main surface of the substrate is lower than the first boiling point while heating the second main surface of the substrate to a temperature equal to or higher than the first boiling point of the first drying liquid. This makes it possible to more reliably suppress boiling of the first drying liquid while bringing the temperature of the first main surface of the substrate closer to the first boiling point of the first drying liquid, thereby suppressing particle adhesion.

[0019] According to the sixth aspect, in the second drying liquid supplying step, the second main surface of the substrate is heated to a temperature equal to or higher than the second boiling point of the second drying liquid, while the second drying liquid is supplied at a flow rate such that the temperature of the first main surface of the substrate is lower than the second boiling point. This makes it possible to more reliably suppress boiling of the second drying liquid while bringing the temperature of the first main surface of the substrate closer to the second boiling point of the second drying liquid, thereby suppressing particle adhesion. Furthermore, because the temperature of the first main surface is closer to the second boiling point, the drying liquid can be evaporated in a shorter time in a state where the surface tension is lower in the subsequent drying step. This effectively reduces the rate of pattern collapse.

[0020] According to the seventh aspect, it is possible to reduce power consumption.

[0021] 1 is a plan view schematically showing an example of the configuration of a substrate processing apparatus; FIG. 2 is a block diagram schematically showing an example of the internal configuration of a control unit; FIG. 3 is a longitudinal sectional view schematically showing an example of the configuration of a processing unit according to a first embodiment; FIG. 4 is a flowchart showing an example of the operation of a processing unit; FIG. 5 is a diagram schematically showing an example of the state of a processing unit in a first drying liquid supplying step; FIG. 6 is a diagram schematically showing an example of the state of a processing unit in a second drying liquid supplying step; FIG. 7 is a timing chart of a processing unit according to a first embodiment, and a first example of the change in the medium temperature of a heat medium over time and the change in the temperature of a second main surface of a substrate over time; FIG. 8 is a timing chart of a processing unit according to a second embodiment, and a first example of the change in the medium temperature of a heat medium, the temperature of a second main surface of a substrate, and the temperature of a first main surface of a substrate over time; FIG. 9 is a timing chart of a processing unit according to a second embodiment, and a second example of the change in the medium temperature of a heat medium, the temperature of a second main surface of a substrate, and the temperature of a first main surface of a substrate over time; 10 is a timing chart of a processing unit according to a third embodiment, and a diagram schematically showing an example of changes over time in the medium temperature of a heat medium and the temperature of a second main surface of a substrate. FIG. 11 is a flowchart showing a first example of the operation of a processing unit according to a fourth embodiment. FIG. 12 is a flowchart showing a second example of the operation of a processing unit according to the fourth embodiment. FIG. 13 is a diagram schematically showing an example of the configuration of a processing unit according to a fifth embodiment.

[0022] 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 ease of understanding. Parts having similar configurations and functions are assigned the same reference numerals, and duplicate explanations will be omitted below.

[0023] In the following description, the same components are denoted by the same reference numerals, and their names and functions are also the same. Therefore, detailed descriptions of them may be omitted to avoid duplication.

[0024] Furthermore, in the following description, even if ordinal numbers such as "first" or "second" are used, these terms are used for convenience to facilitate understanding of the contents of the embodiments, and are not limited to the order that may result from these ordinal numbers.

[0025] When expressions indicating relative or absolute positional relationships (e.g., "in one direction," "along one direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.) are used, unless otherwise specified, the expressions not only strictly represent the positional relationship but also represent a state in which there is a relative displacement in terms of angle or distance within a range in which tolerance or equivalent functionality is obtained. When expressions indicating an equal state (e.g., "identical," "equal," "homogeneous," etc.) are used, the expressions not only represent a state in which there is strict quantitative equality but also represent a state in which there is a difference in which tolerance or equivalent functionality is obtained, unless otherwise specified. When expressions indicating a shape (e.g., "rectangular shape" or "cylindrical shape," etc.) are used, the expressions not only represent a geometrically strict shape but also represent a shape with, for example, irregularities or chamfers within a range in which equivalent effects are obtained. When the expressions "comprise," "include," "have," "includes," "includes," or "have" are used to describe one component, the expressions are not exclusive expressions that exclude the presence of other components. When the phrase "at least one of A, B, and C" is used, the phrase includes A only, B only, C only, any two of A, B, and C, and all of A, B, and C.

[0026] First Embodiment Overall Configuration of Substrate Processing Apparatus Fig. 1 is a plan view schematically showing an example of the configuration of a substrate processing apparatus 100. The substrate processing apparatus 100 is a single-wafer processing apparatus that processes substrates W one by one.

[0027] The substrate W may be, for example, a semiconductor wafer, a liquid crystal display substrate, an organic electroluminescence (EL) (electroluminescence) substrate, an FPD (flat panel display) substrate, an optical display substrate, a magnetic disk substrate, an optical disk substrate, a magneto-optical disk substrate, a photomask substrate, or a solar cell substrate. The substrate W has a thin, flat plate shape with 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. Hereinafter, the substrate W is assumed to be a semiconductor wafer. The substrate W has, for example, a circular plate shape. The diameter of the substrate W is, for example, approximately 300 mm, and the thickness of the substrate W is, for example, approximately 0.5 mm or more and approximately 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.

[0028] 1, the substrate processing apparatus 100 includes an indexer block 110, a processing block 120, and a control unit 90. The processing block 120 is a section that mainly processes substrates W, and the indexer block 110 is a section that mainly transports substrates W between the outside of the substrate processing apparatus 100 and the processing block 120.

[0029] The indexer block 110 includes a load port 111 and a first transport part 112. A substrate container (hereinafter referred to as a carrier) C that has been carried in from outside is placed on the load port 111. The carrier C accommodates a plurality of substrates W, for example, arranged at intervals in the vertical direction. In the example of Fig. 1, a plurality of load ports 111 are arranged.

[0030] The first transport unit 112 is a transport robot and can remove unprocessed substrates W from the carriers C placed on each load port 111. The first transport unit 112 may also be called an indexer robot. The first transport unit 112 transports the unprocessed substrates W removed from the carriers C to the processing block 120. The processing block 120 can process the unprocessed substrates W. The first transport unit 112 can also receive processed substrates W from the processing block 120 and transport the processed substrates W to the carriers C of the load port 111.

[0031] In the example of FIG. 1 , the processing block 120 includes a plurality of processing units 1 and a second transport part 122. The second transport part 122 is a transport robot and can transport substrates W between the first transport part 112 and the plurality of processing units 1. In the example of FIG. 1 , the processing block 120 also includes a receiver 123. The receiver 123 is, for example, a shelf on which a plurality of substrates W can be placed in a vertically arranged state. The first transport part 112 places an unprocessed substrate W on the receiver 123. The second transport part 122 removes the unprocessed substrate W from the receiver 123 and transports the substrate W to the processing unit 1. The processing unit 1 processes the substrate W. The configuration of the processing unit 1 will be described later. The second transport part 122 removes the processed substrate W from the processing unit 1 and transports the substrate W to the receiver 123. The first transport part 112 takes the substrate W from the platform 123 and transports the substrate W to a carrier C in the load port 111 .

[0032] 1 , a plurality of (e.g., four) processing units 1 are arranged to surround the second transport section 122 in a plan view. This second transport section 122 may also be called a center robot. At each position in a plan view, a plurality of processing units 1 may be stacked vertically. In other words, a plurality of (four in the figure) towers TW each made up of a plurality of processing units 1 stacked vertically may be arranged to surround the second transport section 122.

[0033] 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 schematically illustrating an example of the internal configuration of the control unit 90. The control unit 90 is an electronic circuit and includes, for example, a data processing unit 91 and a storage unit 92. In the example illustrated in 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 central processing unit (CPU). The storage unit 92 may include a non-transitory storage unit (e.g., a read-only memory (ROM)) 921 and a temporary storage unit (e.g., a random access memory (RAM)) 922. The non-transitory storage unit 921 may store, for example, a program that defines the processing to be performed by the control unit 90. The data processing unit 91 executes this program, allowing the control unit 90 to perform the processing defined in the program. Of course, some or all of the processing performed by the control unit 90 may be performed by hardware such as a dedicated logic circuit.

[0034] <Overview of Processing Unit> Fig. 3 is a longitudinal cross-sectional view schematically showing an example of the configuration of a processing unit 1 according to the first embodiment. Note that all processing units 1 belonging to the substrate processing apparatus 100 do not need to have the configuration illustrated in Fig. 3. It is sufficient that at least one processing unit 1 of the substrate processing apparatus 100 has the configuration illustrated in Fig. 3.

[0035] The processing unit 1 includes a substrate holding section 2 , a discharge section 3 , and a substrate heating section 4 .

[0036] 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 a 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.

[0037] In the example of Fig. 3, a fan filter unit 11 is provided on the ceiling of chamber 10. The fan filter unit 11 takes in air from outside chamber 10, cleans it, and then blows the cleaned air into chamber 10. Operation of fan filter unit 11 creates a downflow of clean air within chamber 10. In the example of Fig. 3, the upstream end of exhaust pipe 13 is connected to the lower part of the side wall of chamber 10. Gas within chamber 10 is exhausted to the outside through exhaust pipe 13.

[0038] The substrate holder 2 is provided in the chamber 10 and holds the substrate W in a horizontal position while rotating the substrate W around a rotation axis Q1. The horizontal position here means that the thickness direction of the substrate W is aligned with the vertical direction. The rotation axis Q1 is an axis that passes through the center of the substrate W and is aligned with the vertical direction. Such a substrate holder 2 may also be called a spin chuck.

[0039] In this example, the first main surface Wa of the substrate W on which the pattern is formed faces vertically upward. That is, in the example of Fig. 3, the first main surface Wa of the substrate W held by the substrate holder 2 corresponds to the upper surface. The pattern includes, for example, at least one of a wiring pattern, an insulating pattern, and a semiconductor pattern.

[0040] In the example of FIG. 3 , the substrate holder 2 includes a spin base 21, chuck pins 22, and a rotation driver 23. The spin base 21 has a plate-like shape (e.g., a disk shape) and is disposed with its thickness direction aligned vertically. A plurality of chuck pins 22 are provided on the upper surface of the spin base 21. The plurality of chuck pins 22 are disposed at equal intervals along the circumferential direction about the rotation axis Q1. The plurality of chuck pins 22 are disposed so as to be displaceable between a holding position and a release position, which will be described below. The holding position is a position where the chuck pins 22 abut against the periphery of the substrate W. The plurality of chuck pins 22 hold the substrate W by stopping at their respective holding positions. FIG. 3 shows the chuck pins 22 stopped at the holding position. The release position is a position where each chuck pin 22 is separated from the substrate W. The plurality of chuck pins 22 stop at their respective release positions, thereby releasing the substrate W from the holding of the substrate W by the plurality of chuck pins 22. The substrate holder 2 also includes a pin drive unit (not shown) that displaces the chuck pins 22. The pin drive unit includes a drive source such as a motor and an air cylinder, and is controlled by the control unit 90.

[0041] The rotation drive unit 23 includes a shaft 231 and a motor 232. The upper end of the shaft 231 is connected to the lower surface of the spin base 21, and the shaft 231 extends from the lower surface of the spin base 21 along a rotation axis Q1. The motor 232 is controlled by the control unit 90 to rotate the shaft 231 about the rotation axis Q1. This causes the spin base 21, chuck pins 22, and substrate W to rotate integrally about the rotation axis Q1.

[0042] It should be noted that the substrate holder 2 does not necessarily have to have the chuck pins 22. For example, the substrate holder 2 may hold the substrate W by a chuck method such as a vacuum chuck, an electrostatic chuck, or a Bernoulli chuck.

[0043] The discharge unit 3 discharges the processing liquid toward the first main surface Wa of the substrate W held by the substrate holding unit 2. As shown in Fig. 3, the discharge unit 3 includes at least one nozzle 30. The nozzle 30 discharges the processing liquid toward the first main surface Wa of the substrate W held by the substrate holding unit 2. In this case, the first main surface Wa corresponds to the upper surface of the substrate W, and therefore the nozzle 30 is provided vertically above the substrate W held by the substrate holding unit 2. The nozzle 30 is, for example, a straight nozzle that discharges the processing liquid in the form of a continuous flow.

[0044] In the example of FIG. 3 , nozzles 30c, 30w, 30ia, and 30ib are shown as nozzles 30. In the example of FIG. 3 , nozzles 30c, 30w, 30ia, and 30ib extend vertically. In the example of FIG. 3 , nozzle 30c has an outlet 3c formed in its lower surface, nozzle 30w has an outlet 3w formed in its lower surface, nozzle 30ia has an outlet 3ia formed in its lower surface, and nozzle 30ib has an outlet 3ib formed in its lower surface. Nozzle 30c ejects the chemical liquid from outlet 3c, nozzle 30w ejects the rinse liquid from outlet 3w, nozzle 30ia ejects the first drying liquid from outlet 3ia, and nozzle 30ib ejects the second drying liquid from outlet 3ib. The chemical liquid, rinse liquid, first drying liquid, and second drying liquid are all examples of processing liquids, specific examples of which will be described later.

[0045] Nozzles 30c, 30w, 30ia, and 30ib eject the processing liquid toward the center of the first main surface Wa of the substrate W held by the substrate holder 2. In the example of FIG. 3 , nozzles 30c, 30w, 30ia, and 30ib are adjacent to each other in the horizontal direction and fixed to each other. In the example of FIG. 3 , nozzles 30c, 30w, 30ia, and 30ib are provided inside an opposing member 60. The opposing member 60 has, for example, a cylindrical shape. The opposing member 60 has a hollow shape, and the lower end opening of the hollow portion opens at the lower surface of the opposing member 60. Nozzles 30c, 30w, 30ia, and 30ib are provided inside the hollow portion of the opposing member 60, and the processing liquid ejected from each nozzle 30 flows out from the lower end opening of the opposing member 60. In the example of FIG. 3, the facing member 60 is provided at a position vertically facing the center of the substrate W held by the substrate holder 2 .

[0046] The nozzle 30 is connected to the downstream end of a supply pipe 31, and the upstream end of the supply pipe 31 is connected to a processing liquid supply source. In the example of Figure 3, the supply pipes 31 include a supply pipe 31c, a supply pipe 31w, a supply pipe 31ia, and a supply pipe 31ib.

[0047] The downstream end of the supply pipe 31c is connected to the nozzle 30c, 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) that stores the chemical, and supplies the chemical to the upstream end of the supply pipe 31c. Examples of the chemical include hydrofluoric nitric acid obtained by mixing hydrofluoric acid, nitric acid, and water, a hydrofluoric acid-hydrogen peroxide 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). The chemical does not have to be a mixture, but may be a single liquid. For example, a single liquid such as hydrofluoric acid (HF), hydrogen peroxide, or sulfuric acid can be used as the chemical.

[0048] The downstream end of supply pipe 31w is connected to nozzle 30w, and the upstream end of supply pipe 31w is connected to a rinse liquid supply source. The rinse liquid supply source has a tank (not shown) that stores the rinse liquid, and supplies the rinse liquid to the upstream end of supply pipe 31w. The rinse liquid may be, for example, pure water, carbon dioxide water, or ozone water.

[0049] The downstream end of the supply pipe 31ia is connected to the nozzle 30ia, and the upstream end of the supply pipe 31ia is connected to a first drying liquid supply source. The first drying liquid supply source has a tank (not shown) that stores the first drying liquid and supplies the drying liquid to the upstream end of the supply pipe 31ia. The downstream end of the supply pipe 31ib is connected to the nozzle 30ib, and the upstream end of the supply pipe 31ib is connected to a second drying liquid supply source. The second drying liquid supply source has a tank (not shown) that stores the second drying liquid and supplies the drying liquid to the upstream end of the supply pipe 31ib. The surface tension of the second drying liquid is lower than that of the first drying liquid. The miscibility of the first drying liquid and the rinse liquid is higher than that of the second drying liquid and the rinse liquid. The miscibility of the first drying liquid and the second drying liquid is higher than that of the second drying liquid and the rinse liquid, for example. Specifically, an organic solvent such as isopropyl alcohol can be used as the first drying liquid. As the second drying liquid, for example, a fluorine-based organic solvent (organic fluorine compound) such as hydrofluoroolefin can be used.

[0050] The first boiling point of the first drying liquid is different from the second boiling point of the second drying liquid. The first boiling point of the first drying liquid may be lower or higher than the second boiling point of the second drying liquid. When the first drying liquid is isopropyl alcohol, the first boiling point of the first drying liquid is 82.4 degrees Celsius. When the second drying liquid is Opteon (registered trademark) SF70 (methoxyperfluoroheptene), the second boiling point of the second drying liquid is 110.5 degrees Celsius. In this case, the first boiling point of the first drying liquid is lower than the second boiling point of the second drying liquid. When the second drying liquid is Opteon (registered trademark) SF10 (fluoroheptene), the second boiling point of the second drying liquid is 71.5 degrees Celsius. In this case, the first boiling point of the first drying liquid is higher than the second boiling point of the second drying liquid.

[0051] 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, a supply valve 32ia and a flow rate adjustment valve 33ia are inserted in the supply pipe 31ia, and a supply valve 32ib and a flow rate adjustment valve 33ib are inserted in the supply pipe 31ib. The supply valve 32 switches the opening and closing of 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.

[0052] The discharge part 3 discharges various types of processing liquids in the order described below toward the first main surface Wa of the substrate W. This allows the processing unit 1 to sequentially perform various types of processing depending on the types of processing liquids on the first main surface Wa of the substrate W. Specific processing will be described later.

[0053] 3, the facing member 60 is configured to be able to discharge gas toward the first main surface Wa of the substrate W held by the substrate holding part 2. In the example of Fig. 3, the space in the hollow part of the facing member 60 other than the nozzle 30 functions as a gas flow path 30g. A lower end opening in the lower surface of the facing member 60 corresponds to the discharge port of the gas flow path 30g.

[0054] In the example of Figure 3, the upper part of the opposing member 60 is connected to the downstream end of a supply pipe 31g. In other words, the downstream end of the supply pipe 31g is connected to the gas flow path 30g. 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.

[0055] The supply pipe 31g is provided with a supply valve 32g, a flow rate adjustment valve 33g, and a heater 34g. The supply valve 32g switches the supply pipe 31g between on and off. The flow rate adjustment valve 33g adjusts the flow rate of the inert gas flowing through the supply pipe 31g. The heater 34g heats the inert gas flowing through the supply pipe 31g. The heater 34g may be, for example, an electric resistance heater having an electric heating wire. The supply valve 32g, the flow rate adjustment valve 33g, and the heater 34g are controlled by a control unit 90.

[0056] When the supply valve 32g is opened and the heater 34g is activated, high-temperature inert gas is discharged from the center of the lower surface of the facing member 60 (i.e., the lower end opening of the gas flow path 30g) toward the center of the first main surface Wa of the substrate W. This can promote drying of the substrate W.

[0057] In the example of FIG. 3 , the processing unit 1 is provided with a movement driver 35. The movement driver 35 moves the discharge head, which includes the nozzles 30c, 30w, 30ia, and 30ib, and the opposing member 60, as a unit. Specifically, the movement driver 35 moves the discharge head between a processing position and a standby position, which will be described below. The processing position is a position where the nozzles 30c, 30w, 30ia, and 30ib discharge the processing liquid toward the first main surface Wa of the substrate W, for example, a position vertically opposite the center of the first main surface Wa of the substrate W. The processing position is also a position where the opposing member 60 discharges the inert gas toward the first main surface Wa of the substrate W. In the example of FIG. 3 , the discharge head is shown stopped at the processing position. The standby position is a position where the nozzles 30c, 30w, 30ia, and 30ib do not eject the processing liquid toward the first main surface Wa of the substrate W, and is, for example, a position radially outward from the substrate holding part 2. The standby position is also a position where the opposing member 60 does not eject the inert gas toward the first main surface Wa of the substrate W.

[0058] FIG. 3 shows an example of a specific configuration of the movement drive unit 35. In the example of FIG. 3, the movement drive unit 35 includes an arm 351, a support column 352, and a drive source 353. The support column 352 is disposed radially outward of the guard 7 (described later) and extends vertically. The arm 351 extends horizontally, with its tip connected to the discharge head and its base connected to the support column 352. The drive source 353 is controlled by the control unit 90 and rotates the support column 352 in forward and reverse directions within a predetermined angular range around its central axis Q2. The drive source 353 includes, for example, a motor. When the support column 352 rotates in forward and reverse directions within a predetermined angular range around the central axis Q2, the discharge head reciprocates in the circumferential direction about the central axis Q2. The support column 352 is installed so that a processing position and a standby position are located on the movement trajectory of the discharge head. The movement drive unit 35 is not necessarily limited to the embodiment shown in FIG. 3, and may include a direct-acting mechanism such as a linear motor.

[0059] The substrate heating unit 4 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 4 is provided at a position vertically opposite to 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, and therefore the substrate heating unit 4 is provided directly below the substrate W.

[0060] In the example of FIG. 3 , the substrate heating unit 4 includes a nozzle 40. The nozzle 40 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 40 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 portion of the shaft 231 are connected in the vertical direction. A portion of the nozzle 40 is disposed in the through hole. An ejection port is formed in the upper surface of the nozzle 40, and the ejection port of the nozzle 40 faces the center of the second main surface Wb of the substrate W in the vertical direction. The nozzle 40 ejects the heat medium toward the center of the second main surface Wb of the substrate W.

[0061] The downstream end of a supply pipe 41 is connected to the nozzle 40. 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.

[0062] In the example of Fig. 3, a supply pipe 41 is provided with a supply valve 42, a flow rate adjustment valve 43, and a heater 44. The supply valve 42 switches the supply pipe 41 between on and off. The flow rate adjustment valve 43 adjusts the flow rate of the heat medium flowing through the supply pipe 41. The flow rate adjustment valve 43 may be a mass flow controller. The heater 44 heats the heat medium flowing through the supply pipe 41. The heater 44 may be, for example, an electric resistance heater having an electric heating wire. The supply valve 42, the flow rate adjustment valve 43, and the heater 44 are controlled by a control unit 90.

[0063] When the supply valve 42 is opened and the heater 44 is activated, a high-temperature heat medium is discharged from the nozzle 40 onto the central portion of the second main surface Wb of the substrate W. The heat medium that has landed on the central portion of the second main surface Wb of the substrate W is subjected to 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.

[0064] In the example of FIG. 3 , the processing unit 1 is provided with a guard 7 and a guard lifting / lowering drive unit 71. The guard 7 has a cylindrical shape with the rotation axis Q1 as its central axis and surrounds the substrate holder 2. The guard 7 can catch the processing liquid and heat medium splashed from the periphery of the substrate W. The guard lifting / lowering drive unit 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 in the upper position, it can catch 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.

[0065] 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 are provided corresponding to each guard 7. 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 a 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.

[0066] <Example of Operation of Substrate Processing Apparatus> Next, an example of operation of the processing unit 1 will be described. Fig. 4 is a flowchart showing an example of operation of the processing unit 1. The control unit 90 causes the processing unit 1 to perform processes from step S1 to step S8 in accordance with a preset processing procedure (recipe). Fig. 5 is a diagram schematically showing an example of the state of the processing unit 1 in a first drying liquid supplying step described below, and Fig. 6 is a diagram schematically showing an example of the state of the processing unit 1 in a second drying liquid supplying step described below.

[0067] 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 plurality of chuck pins 22 from their respective release positions to their holding positions. As a result, the plurality of chuck pins 22 hold the substrate W. The substrate holding part 2 continues to hold the substrate W until the processing on the substrate W is completed.

[0068] Next, the substrate holder 2 starts rotating the substrate W (step S2: rotation start step). The substrate holder 2 may continue rotating the substrate W until the processing of the substrate W is completed.

[0069] Next, the processing unit 1 supplies the chemical solution to the first main surface Wa of the substrate W (step S3: chemical process). First, the movement driver 35 moves the discharge head to the processing position. The guard lift driver 71 raises the chemical solution guard 7 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. This causes the chemical solution to be discharged from the nozzle 30c toward the first main surface Wa of the rotating substrate W. The chemical solution that has landed on the first main surface Wa of the substrate W flows radially outward due to centrifugal force caused by the rotation of the substrate W and is scattered from the periphery of the substrate W. At this time, the chemical solution acts on the first main surface Wa of the substrate W, thereby performing chemical processing on the first main surface Wa of the substrate W according to the type of chemical solution. For example, the processing unit 1 performs a cleaning process to clean and remove impurities on the first main surface Wa of the substrate W, or an etching process to etch 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 .

[0070] 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 chemical discharge and determines whether the elapsed time is equal to or greater than a predetermined chemical time. The chemical time is set in advance to a time sufficient for the chemical process to be performed sufficiently. The elapsed time is measured, for example, by a timer circuit (not shown) belonging to the control unit 90. When the elapsed time is equal to or greater than the chemical time, the control unit 90 switches the supply valve 32c from an open state to a closed state.

[0071] Next, the processing unit 1 supplies a rinse liquid to the first main surface Wa of the substrate W (step S4: rinse step). If the guard 7 for the rinse liquid is different from the guard 7 for the chemical liquid, the guard lifting / lowering drive unit 71 appropriately raises and lowers the guard 7 to place the guard 7 for the rinse liquid in 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 a closed state to an open state. This causes the rinse liquid to be ejected from the nozzle 30w toward the first main surface Wa of the rotating substrate W. The rinse liquid that has landed on the first main surface Wa of the substrate W flows radially outward due to centrifugal force caused by the rotation of the substrate W and is scattered from the periphery of the substrate W. At this time, the rinse liquid pushes the chemical liquid on the first main surface Wa of the substrate W radially outward. This replaces the processing liquid on the first main surface Wa of the substrate W with the rinse 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 .

[0072] When the chemical liquid has been sufficiently replaced with the rinse 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 the discharge of the rinse liquid, and switches the supply valve 32w from the open state to the closed state when the elapsed time reaches or exceeds a predetermined rinse time. The rinse time is set in advance to a time sufficient to replace the chemical liquid with the rinse liquid.

[0073] Next, the processing unit 1 supplies a first drying liquid to the first main surface Wa of the substrate W (step S5: first drying liquid supply step). If the guard 7 for the first drying liquid is different from the guard 7 for the rinsing liquid, the guard lifting / lowering drive unit 71 raises and lowers the guard 7 appropriately to raise the guard 7 for the first drying liquid to the upper position. Then, the control unit 90 opens the supply valve 32ia. That is, the control unit 90 switches the supply valve 32ia from a closed state to an open state.

[0074] When the supply valve 32ia opens, as shown in Fig. 5, the first drying liquid is discharged from the discharge port 3ia of the nozzle 30ia toward the first main surface Wa of the rotating substrate W. The temperature of the first drying liquid may be, for example, room temperature (e.g., about 25°C). The temperature of the first drying liquid here refers to, for example, the temperature of the first drying liquid at the discharge port 3ia. Furthermore, the room temperature here includes, for example, the temperature of the first drying liquid when a heater for heating the first drying liquid is not provided upstream of the discharge port 3ia or when the heater is not operating. In other words, the room temperature includes the temperature of the unheated first drying liquid.

[0075] The first drying liquid from the nozzle 30ia lands on the center of the first main surface Wa of the substrate W. The first drying liquid that has landed on the first main surface Wa flows radially outward due to centrifugal force caused by the rotation of the substrate W and splashes off from the periphery of the substrate W. At this time, the first drying liquid washes away the rinsing liquid on the first main surface Wa of the substrate W, thereby replacing the processing liquid on the first main surface Wa of the substrate W from the rinsing liquid with the first drying liquid. The processing liquid that has splashed off 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.

[0076] Here, the rotation speed of the substrate W in the first 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. The flow rate of the first drying liquid may be set in advance to, for example, about 100 mL / min or more, more specifically, 250 mL / min or more.

[0077] Furthermore, the processing unit 1 heats the second main surface Wb of the substrate W while supplying the first drying liquid. That is, the substrate heating section 4 heats the second main surface Wb of the substrate W. As a more specific example, the control section 90 opens the supply valve 42 and activates the heater 44. As a result, as shown in FIG. 5 , a high-temperature heat medium (e.g., hot water) is ejected from the nozzle 40 toward the center of the second main surface Wb of the rotating substrate W. 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 caused by 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 first drying liquid on the first main surface Wa. As a result, the first drying liquid on the first main surface Wa of the substrate W is also heated and its temperature increases.

[0078] The substrate heating unit 4 heats the second main surface Wb of the substrate W to a first temperature (first temperature value). The first temperature may be preset to a value corresponding to the first boiling point of the first drying liquid. Here, the second main surface Wb of the substrate W may have the following temperature distribution. That is, in this temperature distribution, the temperature is high at the heat medium landing position (here, the center) and decreases as the temperature moves radially away from the liquid landing position. The first temperature here may be, for example, the maximum value of the temperature distribution. The first temperature may be 60 degrees Celsius or higher, 70 degrees Celsius or higher, or 80 degrees Celsius or higher. The first temperature may be lower than the first boiling point of the first drying liquid. As a specific example, the first temperature may be set to 80 degrees Celsius.

[0079] Specifically, the heater 44 heats the heat medium (hereinafter referred to as the medium temperature) so that its temperature becomes a first medium temperature (first medium temperature value). The medium temperature of the heat medium here refers to, for example, the temperature of the heat medium at the outlet of the nozzle 40. The first medium temperature may be, for example, 60°C or higher, 70°C or higher, or 80°C or higher. As a specific example, the first medium temperature may be set to 80°C. The first medium temperature may be lower than the first boiling point of the first drying liquid. For example, when the heat medium is water, the first medium temperature may be set to less than 90°C, which is 10°C lower than the boiling point of the heat medium (100°C). This allows compliance with SEMI standards.

[0080] The flow rate control valve 43 may adjust the flow rate of the heat medium to, for example, a value greater than the flow rate of the first drying liquid. More specifically, the flow rate control valve 43 may adjust the flow rate of the heat medium to 1000 mL / min or more, or 1500 mL / min or more.

[0081] As described above, in the first drying liquid supplying step, the processing unit 1 supplies the first drying liquid to the first main surface Wa of the substrate W while heating the second main surface Wb of the substrate W. This also increases the temperature of the first drying liquid on the first main surface Wa of the substrate W. Increasing the temperature of the first drying liquid can increase the efficiency of replacement of the rinse liquid with the first drying liquid.

[0082] When the rinsing liquid has been sufficiently replaced with the first drying liquid, the control unit 90 closes the supply valve 32ia. As a specific example, the control unit 90 measures the elapsed time from the start of ejection of the first drying liquid, and switches the supply valve 32ia from the open state to the closed state when the elapsed time is equal to or longer than a predetermined first drying liquid supply time. The first drying liquid supply time is set in advance to a time sufficient to replace the rinsing liquid with the first drying liquid.

[0083] Next, the processing unit 1 supplies the second drying liquid to the first main surface Wa of the substrate W (step S6: second drying liquid supply step). If the guard 7 for the second drying liquid is different from the guard 7 for the first drying liquid, the guard lifting / lowering drive unit 71 raises and lowers the guard 7 appropriately to raise the guard 7 for the second drying liquid to the upper position. Then, the control unit 90 opens the supply valve 32ib. That is, the control unit 90 switches the supply valve 32ib from a closed state to an open state.

[0084] When the supply valve 32ib opens, as shown in Fig. 6, the second drying liquid is discharged from the discharge port 3ib of the nozzle 30ib toward the first main surface Wa of the rotating substrate W. The temperature of the second drying liquid may be, for example, room temperature (e.g., 25°C). The temperature of the second drying liquid here refers to, for example, the temperature of the second drying liquid at the discharge port 3ib. Furthermore, the room temperature here includes, for example, the temperature of the second drying liquid when a heater for heating the second drying liquid is not provided upstream of the discharge port 3ib or when the heater is not operating. In other words, the room temperature includes the temperature of the unheated second drying liquid.

[0085] The second drying liquid from the nozzle 30ib lands on the center of the first main surface Wa of the substrate W. The second drying liquid that has landed on the first main surface Wa flows radially outward due to centrifugal force caused by the rotation of the substrate W, and is scattered from the periphery of the substrate W. At this time, the second drying liquid pushes away the first drying liquid on the first main surface Wa of the substrate W, thereby replacing the first drying liquid with the second drying liquid on the first main surface Wa of the substrate W. The processing liquid that has 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.

[0086] Here, the rotation speed of the substrate W in the second 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. The flow rate of the second drying liquid may be set in advance to, for example, about 100 mL / min or more, more specifically, 250 mL / min or more.

[0087] Furthermore, the processing unit 1 heats the second main surface Wb of the substrate W when supplying the second drying liquid. That is, the substrate heating part 4 heats the second main surface Wb of the substrate W. As a more specific example, the control part 90 opens the supply valve 42 and activates the heater 44. As a result, as shown in FIG. 6 , a high-temperature heat medium (e.g., hot water) is ejected from the nozzle 40 toward the center of the second main surface Wb of the rotating substrate W. This also heats the substrate W and the second drying liquid on the first main surface Wa of the substrate W.

[0088] The substrate heater 4 heats the second main surface Wb of the substrate W to a second temperature (second temperature value). The second temperature may be preset to a value corresponding to the second boiling point of the second drying liquid. The second temperature is, for example, the maximum value in the temperature distribution on the second main surface Wb. As a specific example, the second boiling point of the second drying liquid is higher than the first boiling point of the first drying liquid. For example, if the first drying liquid and the second drying liquid are isopropyl alcohol and hydrofluoroolefin, respectively, the second boiling point of the second drying liquid (110.5°C) is higher than the first boiling point of the first drying liquid (82.4°C). In this case, the second temperature is set higher than the temperature of the second main surface Wb of the substrate W in the first drying liquid supplying step (here, the first temperature). For example, the second temperature may be 60°C or higher, 70°C or higher, or 80°C or higher. The second temperature may also be higher than the first boiling point of the first drying liquid. The second temperature may be lower than the second boiling point of the second drying liquid. As a specific example, the second temperature may be set to about 89.9 degrees Celsius.

[0089] Specifically, the heater 44 heats the heat medium so that its medium temperature reaches a second medium temperature (second medium temperature value). In the example of FIG. 7 , the second medium temperature is higher than the medium temperature (first medium temperature) of the heat medium in the first drying liquid supplying step. The second medium temperature may be, for example, 60°C or higher, 70°C or higher, or 80°C or higher. The second medium temperature may also be higher than the first boiling point of the first drying liquid. The second medium temperature may also be lower than the second boiling point of the second drying liquid. For example, when the heat medium is water, the second medium temperature may be set to less than 90°C, which is 10°C lower than the boiling point of the heat medium (100°C). This allows compliance with SEMI standards. As a specific example, the second medium temperature may be set to approximately 89.9°C.

[0090] The flow rate control valve 43 may adjust the flow rate of the heat medium to, for example, a value greater than the flow rate of the second drying liquid. More specifically, the flow rate control valve 43 may adjust the flow rate of the heat medium to 1000 mL / min or more, or 1500 mL / min or more.

[0091] As described above, in the second drying liquid supplying step, the processing unit 1 supplies the second drying liquid to the first main surface Wa of the substrate W while heating the second main surface Wb of the substrate W. This also increases the temperature of the second drying liquid on the first main surface Wa of the substrate W. By increasing the temperature of the second drying liquid, it is possible to increase the efficiency of replacement of the first drying liquid with the second drying liquid.

[0092] When the first drying liquid has been sufficiently replaced with the second drying liquid, the processing unit 1 dries the substrate W (step S7: drying process). Specifically, the processing unit 1 measures the elapsed time from the start of ejection of the second drying liquid and determines whether the elapsed time is equal to or longer than a predetermined second drying liquid supply time. The second drying liquid supply time is set in advance to a time sufficient to replace the first drying liquid with the second drying liquid. The second drying liquid supply time is set, for example, to at least several tens of seconds, and as a specific example, may be set to approximately 40 seconds. Then, when the elapsed time is equal to or longer than the second drying liquid supply time, the processing unit 1 dries the substrate W. Specifically, the control unit 90 closes the supply valve 32ib. Furthermore, the substrate heating unit 4 stops heating the second main surface Wb of the substrate W.

[0093] Furthermore, the control unit 90 controls the substrate holding unit 2 to increase the rotation speed of the substrate W. For example, the substrate holding unit 2 may rotate the substrate W at a rotation speed of 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. Alternatively, the substrate holding unit 2 may gradually (e.g., stepwise) increase the rotation speed of the substrate W.

[0094] The processing unit 1 may supply inert gas toward the center of the first main surface Wa of the substrate W. Specifically, the control unit 90 may open the supply valve 32g and operate the heater 34g. This causes high-temperature inert gas to be discharged toward the center of the first main surface Wa of the substrate W from a gas discharge port in the center of the lower surface of the facing member 60 (i.e., the lower end port of the gas flow path 30g). The inert gas that hits the center of the first main surface Wa of the substrate W flows radially outward along the first main surface Wa. The heater 34g may heat the inert gas to, for example, 60°C or higher, 70°C or higher, or 80°C 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 30g. The flow rate adjustment valve 33g may adjust the flow rate of the inert gas to, for example, 10 L / min or higher and 300 L / min or lower.

[0095] When the second drying liquid has sufficiently evaporated, the processing unit 1 stops the discharge of the inert gas and stops the rotation of the substrate W. As a specific example, the control unit 90 measures the elapsed time since the discharge of the second drying liquid stopped and determines whether the measured time is equal to or longer than a predetermined drying time. The drying time is set in advance to a time sufficient for the substrate W to be sufficiently dried. When the elapsed time is equal to or longer than the drying time, the control unit 90 switches the supply valve 32g from an open state to a closed state and causes the substrate holder 2 to stop the rotation of the substrate W. In addition, the movement drive unit 35 moves the discharge head to the standby position, and the guard lift drive unit 71 lowers the guard 7 to the down position.

[0096] Next, the substrate holder 2 releases the hold on the substrate W (step S8: hold releasing step).Then, the second transporter 122 carries the processed substrate W out of the processing unit 1.

[0097] As described above, the processing unit 1 can process the substrate W. Moreover, in this embodiment, a first drying liquid supply process is performed after a liquid supply process including a chemical liquid process and a rinsing process, and then a second drying liquid supply process is performed. Figure 7 is a timing chart of the processing unit 1 according to the first embodiment, and is a diagram schematically showing a first example of the change in medium temperature of the heat medium over time and the change in temperature of the second main surface Wb of the substrate W over time. In the example of Figure 7, the maximum value of the temperature distribution of the second main surface Wb is shown as the temperature of the second main surface Wb of the substrate W. This point is also true for other drawings referred to later.

[0098] 7 , at time t1, the control unit 90 switches the supply valve 32ia from a closed state to an open state. As a result, the first drying liquid begins to be discharged from the nozzle 30ia toward the first main surface Wa of the substrate W. At this time t1, the first drying liquid supply step essentially begins. That is, the process of replacing the rinse liquid with the first drying liquid begins. Because the miscibility of the rinse liquid and the first drying liquid is higher than the miscibility of the rinse liquid and the second drying liquid, the processing liquid on the substrate W can be replaced from the rinse liquid with the first drying liquid with higher replacement efficiency than when the rinse liquid is replaced with the second drying liquid.

[0099] The control unit 90 switches the supply valve 42 from a closed state to an open state, for example, at time t1, and activates the heater 44. As a result, a high-temperature heat medium is ejected from the nozzle 40 toward the second main surface Wb of the substrate W, heating the substrate W. This makes it possible to heat the first drying liquid on the first main surface Wa of the substrate W as well. Because the temperature of the first drying liquid on the first main surface Wa of the substrate W is high, the efficiency of replacing the rinse liquid with the first drying liquid can be improved. Therefore, at the end of the first drying liquid supply step, the amount of remaining rinse liquid, which has a high surface tension, can be further reduced.

[0100] 7 , the medium temperature of the heat medium (first medium temperature) in the first drying liquid supply step is lower than the first boiling point bp1 of the first drying liquid. Therefore, the temperature of the first main surface Wa of the substrate W is also lower than the first boiling point bp1. This makes it possible to more reliably suppress boiling of the first drying liquid on the first main surface Wa of the substrate W. If the first drying liquid on the first main surface Wa boils during supply of the first drying liquid, this will result in adhesion of particles to the first main surface Wa. In the above example, boiling of the first drying liquid can be more reliably suppressed, and therefore adhesion of particles can be more reliably suppressed.

[0101] 7 , at time t2, the control unit 90 switches the supply valve 32ia from an open state to a closed state, and switches the supply valve 32ib from a closed state to an open state. At this time t2, the actual second drying liquid supplying step begins. That is, the process of replacing the first drying liquid with the second drying liquid begins. Since the miscibility between the first drying liquid and the second drying liquid is higher than the miscibility between the rinse liquid and the second drying liquid, the processing liquid on the substrate W can be replaced from the first drying liquid with the second drying liquid with higher replacement efficiency than the replacement of the rinse liquid with the second drying liquid.

[0102] In the example of Figure 7, the supply valve 42 remains open after time t2. As a result, the high-temperature heat medium is ejected from the nozzle 40 toward the second main surface Wb of the substrate W, heating the substrate W. This also heats the second drying liquid on the first main surface Wa of the substrate W. In the example of Figure 7, the second boiling point bp2 of the second drying liquid is higher than the first boiling point bp1 of the first drying liquid. Therefore, the second temperature is set higher than the first temperature. That is, in the first drying liquid supply step, the substrate heating unit 4 heats the second main surface Wb of the substrate W to a lower first temperature corresponding to the lower first boiling point bp1 of the first drying liquid, and in the second drying liquid supply step, the substrate heating unit 4 heats the second main surface Wb of the substrate W to a higher second temperature corresponding to the higher second boiling point bp2 of the second drying liquid. That is, the heater 44 increases the amount of heat applied to the heat medium at time t2, thereby raising the medium temperature of the heat medium from the first medium temperature to the second medium temperature.

[0103] Therefore, in the second drying liquid supplying step, the temperature of the second drying liquid on the first main surface Wa of the substrate W can be further increased. In other words, the temperature of the second drying liquid on the first main surface Wa of the substrate W can be brought closer to the second boiling point bp2. This further increases the efficiency of replacing the first drying liquid with the second drying liquid, thereby further reducing the amount of remaining first drying liquid, which has a high surface tension, at the end of the second drying liquid supplying step. In addition, in the example of FIG. 7 , the second medium temperature of the heat medium is equal to or higher than the first boiling point bp1 of the first drying liquid, and the second temperature of the second main surface Wb of the substrate W is also equal to or higher than the first boiling point bp1 of the first drying liquid. This allows the temperature of the second drying liquid on the first main surface Wa of the substrate W to be raised to a higher level. In other words, the temperature of the second drying liquid on the first main surface Wa of the substrate W can be brought closer to the second boiling point bp2, thereby further increasing the efficiency of replacing the first drying liquid with the second drying liquid.

[0104] 7 , the second medium temperature of the heat medium is lower than the second boiling point bp2 of the second drying liquid, and therefore the temperature of the first main surface Wa of the substrate W is also lower than the second boiling point bp2. This makes it possible to more reliably suppress boiling of the second drying liquid on the first main surface Wa of the substrate W. Therefore, it is possible to more reliably suppress adhesion of particles.

[0105] Then, in the drying step, the second drying liquid on the first main surface Wa of the substrate W evaporates, drying the substrate W. First, from the viewpoint of liquid material, the surface tension of the second drying liquid is smaller than that of the first drying liquid, which reduces the rate of collapse of the pattern on the first main surface Wa of the substrate W during drying.

[0106] Furthermore, after the liquid supplying step, a first drying liquid supplying step is performed, followed by a second drying liquid supplying step. That is, in the first drying liquid supplying step, the rinse liquid is replaced with a first drying liquid that is highly miscible with the rinse liquid. Then, in the second drying liquid supplying step, the first drying liquid is replaced with a second drying liquid that is highly miscible with the first drying liquid. Therefore, in terms of liquid materials, the rinse liquid can be replaced with the first drying liquid, and the first drying liquid can be replaced with the second drying liquid, with high replacement efficiency. Therefore, at the end of the second drying liquid supplying step, the remaining amounts of the rinse liquid and the first drying liquid, which have high surface tensions, can be reduced. This also reduces the rate of pattern collapse.

[0107] Furthermore, in the first drying liquid supplying step, the first drying liquid on the first main surface Wa of the substrate W is heated, so that the processing liquid on the substrate W is replaced with the first drying liquid with higher replacement efficiency from the viewpoint of temperature as well, thereby reducing the amount of remaining rinse liquid at the end of the second drying liquid supplying step.

[0108] Furthermore, in the second drying liquid supplying step, the second drying liquid on the first main surface Wa of the substrate W is heated to a higher temperature, so the amount of remaining first drying liquid can also be reduced. This also reduces the rate of pattern collapse. Moreover, in the drying step, the second drying liquid evaporates at a higher temperature. Therefore, the second drying liquid can evaporate in a shorter time. Since the surface tension decreases as the temperature increases, the second drying liquid evaporates with a low surface tension. This reduction in surface tension and increase in evaporation rate due to temperature also reduces the rate of pattern collapse.

[0109] In the above example, the first boiling point bp1 of the first drying liquid is lower than the second boiling point bp2 of the second drying liquid, but the first boiling point bp1 of the first drying liquid may be higher than the second boiling point bp2 of the second drying liquid. Figure 8 is a timing chart of the processing unit 1 according to the first embodiment, and a second example of the change in the medium temperature of the heat medium over time and the change in the temperature of the second main surface Wb of the substrate W over time.

[0110] 8, the first boiling point bp1 of the first drying liquid is higher than the second boiling point bp2 of the second drying liquid. For example, when the first drying liquid and the second drying liquid are isopropyl alcohol and fluoroheptene, respectively, the first boiling point bp1 of the first drying liquid (82.4°C) is higher than the second boiling point bp2 of the second drying liquid (71.5°C).

[0111] In this case, in the second drying liquid supplying step, the substrate heating unit 4 heats the second main surface Wb of the substrate W to a second temperature lower than the first temperature. To summarise the examples in Figures 7 and 8 , when the first boiling point bp1 is lower than the second boiling point bp2, the first temperature is lower than the second temperature, and when the first boiling point bp1 is higher than the second boiling point bp2, the first temperature is higher than the second temperature. In other words, the sign of the value obtained by subtracting the second temperature from the first temperature is equal to the sign of the value obtained by subtracting the second boiling point bp2 of the second drying liquid from the first boiling point bp1 of the first drying liquid.

[0112] In the example of Fig. 8, the first medium temperature is higher than the second medium temperature. This allows the first temperature to be higher than the second temperature. To sum up the examples of Fig. 7 and Fig. 8, the positive and negative sign of the value obtained by subtracting the second temperature from the first temperature is equal to the positive and negative sign of the value obtained by subtracting the second medium temperature from the first medium temperature.

[0113] 8 , in the first drying liquid supplying step, the temperature of the second main surface Wb of the substrate W is adjusted to the higher first temperature. This allows the temperature of the first drying liquid on the first main surface Wa of the substrate W to be brought closer to the first boiling point bp1. Therefore, in the first drying liquid supplying step, the processing liquid on the first main surface Wa of the substrate W can be replaced from the rinsing liquid with the first drying liquid with higher replacement efficiency.

[0114] On the other hand, in the second drying liquid supplying step, the temperature of the second main surface Wb of the substrate W is adjusted to a second temperature that is lower than the first temperature. Therefore, in the second drying liquid supplying step, boiling of the second drying liquid on the second main surface Wb can be further suppressed. Moreover, since the substrate W is heated, the first drying liquid is replaced with the second drying liquid with higher replacement efficiency than when the substrate W is not heated.

[0115] In the example of Fig. 8, the first temperature is equal to or higher than the second boiling point bp2 of the second drying liquid. Regarding this point, integrating Figs. 7 and 8, the higher of the first and second temperatures (the second temperature in Fig. 7 and the first temperature in Fig. 8) is equal to or higher than the lower of the first boiling point bp1 and the second boiling point bp2 (the first boiling point bp1 in Fig. 7 and the second boiling point bp2 in Fig. 8). In the example of Fig. 8, since the first temperature is equal to or higher than the second boiling point bp2, the temperature of the first drying liquid on the first main surface Wa of the substrate W can be raised to a higher level in the first drying liquid supplying step. This allows the processing liquid on the first main surface Wa of the substrate W to be replaced with the first drying liquid from the rinse liquid with higher replacement efficiency.

[0116] 8, the first temperature is lower than the first boiling point bp1 of the first drying liquid, and the second temperature is lower than the second boiling point bp2 of the second drying liquid. This more reliably suppresses boiling of the first drying liquid in the first drying liquid supplying step, and more reliably suppresses boiling of the second drying liquid in the second drying liquid supplying step. This more reliably suppresses particle adhesion.

[0117] Furthermore, the substrate heating section 4 supplies a heat medium to the second main surface Wb of the substrate W to heat the substrate W. This allows the substrate heating section 4 to heat the second main surface Wb of the substrate W with a simple configuration. More specifically, the substrate heating section 4 can heat the second main surface Wb of the substrate W to both a first temperature corresponding to the first boiling point bp1 of the first drying liquid and a second temperature corresponding to the second boiling point bp2 of the second drying liquid with a simple configuration.

[0118] In the first embodiment described above, the substrate heating unit 4 heats the second main surface Wb of the substrate W throughout the entire first drying liquid supply step. That is, the substrate heating unit 4 heats the second main surface Wb of the substrate W throughout the entire first drying liquid supply time. However, the substrate heating unit 4 may also heat the second main surface Wb of the substrate W during at least a portion of the first drying liquid supply step. This also makes it possible to increase the temperature of the first drying liquid on the first main surface Wa of the substrate W during that period, thereby improving the replacement efficiency during that period. Similarly, the substrate heating unit 4 may heat the second main surface Wb of the substrate W during at least a portion of the second drying liquid supply step.

[0119] Furthermore, although the discharge unit 3 discharges the first drying liquid and the second drying liquid at room temperature in the above example, it may discharge the first drying liquid or the second drying liquid at a high temperature. For example, the discharge unit 3 may further include at least one of a first heater (not shown) and a second heater (not shown). The first heater is provided in the supply pipe 31ia and heats the first drying liquid flowing through the supply pipe 31ia. The second heater is provided in the supply pipe 31ib and heats the second drying liquid flowing through the supply pipe 31ib. The first heater and the second heater are controlled by the control unit 90. The first heater heats the first drying liquid so that the temperature of the first drying liquid is higher than room temperature and lower than the first boiling point bp1 of the first drying liquid. For example, the first heater may raise the temperature of the first drying liquid to 60°C or higher, and as a specific example, may raise the temperature to approximately 70°C. The second heater heats the second drying liquid so that the temperature of the second drying liquid is higher than room temperature and lower than the second boiling point bp2 of the second drying liquid. For example, the second heater may raise the temperature of the second drying liquid to 60°C or higher, and as a specific example, may raise the temperature to about 70°C.

[0120] Second Embodiment The configuration of the substrate processing apparatus 100 according to the second embodiment is similar to that of the first embodiment. However, in the second embodiment, in the first drying liquid supplying step (step S5), the substrate heating unit 4 may heat at least a portion (e.g., the central portion) of the second main surface Wb of the substrate W to a temperature equal to or higher than the first boiling point bp1 of the first drying liquid. Specifically, the substrate heating unit 4 may supply a heat medium having a temperature equal to or higher than the first boiling point bp1 of the first drying liquid to the central portion of the second main surface Wb of the substrate W. Alternatively, in the second drying liquid supplying step (step S6), the substrate heating unit 4 may heat at least a portion (e.g., the central portion) of the second main surface Wb of the substrate W to a temperature equal to or higher than the second boiling point bp2 of the second drying liquid. Specifically, the substrate heating unit 4 may supply a heat medium having a temperature equal to or higher than the second boiling point bp2 of the second drying liquid to the central portion of the second main surface Wb of the substrate W. This will be described in detail below.

[0121] 9 is a timing chart of the processing unit 1 according to the second embodiment, and is a diagram schematically illustrating a first example of changes over time in the medium temperature of the heat medium, the temperature of the second main surface Wb of the substrate W, and the temperature of the first main surface Wa of the substrate W. In the example of Fig. 9, the first boiling point bp1 of the first drying liquid is lower than the second boiling point bp2 of the second drying liquid.

[0122] 9 , in the first drying liquid supplying step (step S5), the first medium temperature of the heat medium discharged from the nozzle 40 is higher than the first boiling point bp1 of the first drying liquid. When the first drying liquid is isopropyl alcohol, the first boiling point bp1 is 82.4 degrees Celsius, and the first medium temperature of the heat medium is set to, for example, about 85 degrees Celsius. Therefore, the temperature of the portion (e.g., the center) where the heat medium lands on the second main surface Wb of the substrate W is also higher than the boiling point of the first drying liquid.

[0123] On the other hand, in the first drying liquid supply step, the first drying liquid, which has a lower temperature than the heat medium, is ejected from the nozzle 30ia. Therefore, the low-temperature first drying liquid is continuously supplied to the first main surface Wa of the substrate W. Therefore, the low-temperature first drying liquid can cool the first main surface Wa of the substrate W. The cooling capacity of the first drying liquid increases as the flow rate of the first drying liquid increases. Therefore, the flow rate adjustment valve 33ia adjusts the flow rate of the first drying liquid to a value that will cause the temperature of the first main surface Wa of the substrate W to be less than the first boiling point bp1. For example, the flow rate of the first drying liquid is preset to approximately 100 mL / min or more, and more specifically, can be set to 250 mL / min or more.

[0124] 9, the temperature of the first main surface Wa of the substrate W is shown as the temperature of the central portion of the first main surface Wa of the substrate W. Since the high-temperature heat medium lands on the central portion of the second main surface Wb of the substrate W, the temperature of the first main surface Wa of the substrate W has a temperature distribution described below. That is, the temperature is high at the central portion of the substrate W and decreases radially outward. For this reason, in the example of FIG. 9, the highest value in the temperature distribution on the first main surface Wa of the substrate W is shown as the temperature of the first main surface Wa.

[0125] 9 , the temperature of the first main surface Wa of the substrate W in the first drying liquid supplying step is lower than the first boiling point bp1 of the first drying liquid. When the first drying liquid is isopropyl alcohol, the highest temperature in the temperature distribution on the first main surface Wa of the substrate W can be adjusted to, for example, about 80° C. or lower. This makes it possible to more reliably suppress boiling of the first drying liquid in the first drying liquid supplying step. This also makes it possible to more reliably suppress adhesion of particles to the first main surface Wa of the substrate W.

[0126] Moreover, in the above example, the first medium temperature of the heat medium discharged in the first drying liquid supplying step is equal to or higher than the first boiling point bp1, so that in the first 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 first boiling point bp1.

[0127] In the second embodiment, in the first drying liquid supplying step, the temperature of the substrate W itself can be increased while the temperature of the first drying liquid on the first main surface Wa of the substrate W can be brought closer to the first boiling point bp1. This allows the processing liquid on the first main surface Wa of the substrate W to be replaced from the rinse liquid with the first drying liquid with higher replacement efficiency. This makes it possible to further reduce the amount of residual rinse liquid and further reduce the rate of pattern collapse.

[0128] In the example of FIG. 9 , in the second drying liquid supplying step (step S6), the second medium temperature of the heat medium discharged from the nozzle 40 is lower than the second boiling point bp2 of the second drying liquid. Here, the second drying liquid is methoxyperfluoroheptene, and the heat medium is water. That is, the second boiling point bp2 is 110.5 degrees Celsius, and the boiling point of the heat medium is 100 degrees Celsius. Therefore, the second boiling point bp2 is higher than the boiling point of the heat medium. Since the medium temperature of the heat medium must be set below the boiling point of the heat medium, the second medium temperature of the heat medium in the second drying liquid supplying step is set to, for example, about 89.9 degrees Celsius, as in the first embodiment. Therefore, the second temperature is also lower than the boiling point of the heat medium, and therefore lower than the second boiling point bp2 of the second drying liquid.

[0129] 9, the second temperature is higher than the first temperature, and therefore, similarly to the first embodiment, the temperature of the second drying liquid on the first main surface Wa of the substrate W can be made higher in the second drying liquid supplying step, thereby reducing the pattern collapse rate similarly to the first embodiment.

[0130] Next, a case where the first boiling point bp1 is higher than the second boiling point bp2 will be described. Fig. 10 is a timing chart of the processing unit 1 according to the second embodiment, and is a diagram schematically showing a second example of the changes over time in the medium temperature of the heat medium, the temperature of the second main surface Wb of the substrate W, and the temperature of the first main surface Wa of the substrate W. In the example of Fig. 10, the first boiling point bp1 of the first drying liquid is higher than the second boiling point bp2 of the second drying liquid. The second drying liquid supply step (step S6) is different from Fig. 9 .

[0131] 10 , in the second drying liquid supplying step (step S6), the substrate heating unit 4 heats at least a portion (here, the center portion) of the second main surface Wb of the substrate W to a temperature equal to or higher than the second boiling point bp2 of the second drying liquid. Note that the second boiling point bp2 is lower than the first boiling point bp1. Therefore, in the example of FIG. 10 , similar to the first embodiment, the substrate heating unit 4 heats the second main surface Wb of the substrate W to a second temperature lower than the first temperature. Specifically, the second medium temperature of the heat medium discharged from the nozzle 40 is lower than the first medium temperature and higher than the second boiling point bp2 of the second drying liquid. Here, the second drying liquid is fluoroheptene, and the second boiling point bp2 is 71.5°C. The second medium temperature of the heat medium can be set to, for example, approximately 75°C.

[0132] Furthermore, in the second drying liquid supplying step, second drying liquid having a lower temperature than the heat medium is discharged from the nozzle 30ib. The cooling capacity of this second drying liquid increases as the flow rate of the second drying liquid increases. Therefore, the flow rate adjustment valve 33ib adjusts the flow rate of the second drying liquid to a value that causes the temperature of the first main surface Wa of the substrate W to be less than the second boiling point bp2. For example, the flow rate of the second drying liquid is preset to approximately 100 mL / min or more, and more specifically, can be set to 250 mL / min or more.

[0133] 10 , the temperature of the first main surface Wa of the substrate W in the second drying liquid supplying step is lower than the second boiling point bp2 of the second drying liquid. The highest temperature in the temperature distribution of the first main surface Wa of the substrate W can be adjusted to, for example, about 70° C. or lower. This makes it possible to more reliably suppress boiling of the second drying liquid in the second drying liquid supplying step. This also makes it possible to more reliably suppress adhesion of particles to the first main surface Wa of the substrate W.

[0134] Moreover, in the above example, the second medium temperature of the heat medium discharged in the second drying liquid supplying step is equal to or higher than the second boiling point bp2. Therefore, in the second 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 second boiling point bp2. This allows the processing liquid on the first main surface Wa of the substrate W to be replaced from the first drying liquid with the second drying liquid with higher replacement efficiency. Furthermore, in the drying step immediately after the supply of the second drying liquid is stopped, the temperature of the second drying liquid on the first main surface Wa of the substrate W can be increased. Therefore, in the drying step, the surface tension of the second drying liquid can be further reduced, while the evaporation rate of the second drying liquid can be further increased. This further reduces the rate of pattern collapse.

[0135] In the specific examples of the first and second embodiments, the substrate heating unit 4 heats the second main surface Wb of the substrate W to the second temperature throughout the entire second drying liquid supply time in the second drying liquid supply step (step S6). However, this is not necessarily limited to this.

[0136] 11 is a timing chart of the processing unit 1 according to the third embodiment, and is a diagram schematically illustrating an example of changes over time in the medium temperature of the heat medium and the temperature of the second main surface Wb of the substrate W. In the example of Fig. 11, the second boiling point bp2 of the second drying liquid is higher than the first boiling point bp1 of the first drying liquid. Therefore, in the example of Fig. 11, the second temperature is higher than the first temperature.

[0137] 11 , the medium temperature of the heat medium remains at the first medium temperature even after time t2, and then rises from the first medium temperature to the second medium temperature at time t23, which is after time t2. That is, the control unit 90 controls the heater 44 to raise the medium temperature of the heat medium at time t23. Specifically, the heater 44 increases the amount of heat applied to the heat medium at time t23, thereby raising the medium temperature of the heat medium from the first medium temperature to the second medium temperature. Then, the control unit 90 switches the supply valve 42 from the open state to the closed state at time t3, which is after time t23.

[0138] For this reason, the substrate heating unit 4 heats the second main surface Wb of the substrate W to the second temperature during a predetermined later time T2 from time t23 to time t3 during the second drying liquid supply time T from time t2 to time t3. Meanwhile, in the example of FIG. 11 , during the earlier time T1 from time t2 to time t23, the temperature of the second main surface Wb of the substrate W is lower than the second temperature and, as a more specific example, may be maintained at the first temperature. The later time T2 is preset to a time sufficient to bring the temperature of the first main surface Wa of the substrate W at time t3 close to the second boiling point bp2 of the second drying liquid. For example, the later time T2 may be set to half or less of the second drying liquid supply time T, or to one-third or less, one-quarter or less, or one-tenth or less of the second drying liquid supply time T.

[0139] As described above, in the third embodiment, the substrate heating unit 4 heats the second main surface Wb of the substrate W to the second temperature at the later time T2, and keeps the temperature of the second main surface Wb of the substrate W lower than the second temperature at the earlier time T1. This reduces the power consumption of the substrate heating unit 4, and therefore the power consumption of the substrate processing apparatus 100. Moreover, because the temperature of the second drying liquid on the first main surface Wa of the substrate W is sufficiently high at time t3, the second drying liquid can evaporate with a smaller surface tension and in a shorter evaporation time during the drying process. This reduces the rate of pattern collapse.

[0140] 11 , although the substrate heating unit 4 supplies a high-temperature heat medium to the second main surface Wb of the substrate W during the previous time T1, the substrate heating unit 4 may not be heating the second main surface Wb of the substrate W during the previous time T1. In this case, the substrate heating unit 4 does not supply a heat medium, so the amount of heat medium used can be reduced. If the heat medium is a liquid, liquid conservation can be achieved. Furthermore, replacement efficiency can be improved during the subsequent time T2 after replacement of the first drying liquid with the second drying liquid has progressed to a certain extent. Therefore, it is easier to reduce the amount of remaining first drying liquid compared to when the second main surface Wb of the substrate W is heated to the second temperature during the previous time T1.

[0141] In the above example, the processing unit 1 performed the chemical liquid step (step S3), the rinsing step (step S4), the first drying liquid supply step (step S5), the second drying liquid supply step (step S6), and the drying step (step S7) in this order. However, this is not necessarily limited to this.

[0142] Fig. 12 is a flowchart showing a first example of the operation of the processing unit 1 according to the fourth embodiment. In the example of Fig. 12, the control unit 90 causes the processing unit 1 to perform processes from step S11 to step S20 in accordance with a preset processing procedure (recipe). Steps S11 to S15 are similar to steps S1 to S5, respectively. However, in step S15 (first drying liquid supply step), the substrate heating unit 4 does not have to heat the substrate W.

[0143] Next, the processing unit 1 hydrophobizes 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 hydrophobizing liquid, and ejects the hydrophobizing liquid from the nozzle onto the first main surface Wa of the rotating substrate W. The hydrophobizing liquid includes, for example, a silicon-based hydrophobizing liquid. The silicon-based hydrophobizing liquid is a hydrophobizing liquid that hydrophobizes silicon (Si) itself and compounds containing silicon. The hydrophobizing liquid is, for example, a silylation liquid that includes a liquid silylation agent (also called a silane coupling agent). The processing unit 1 stops ejecting the hydrophobizing liquid from the nozzle when the first main surface Wa of the substrate W has been sufficiently hydrophobized.

[0144] Next, the processing unit 1 executes steps S17 to S20, which are similar to steps S5 to S8, respectively.

[0145] As described above, in the first example described above, the first drying liquid supply step (step S17) and the second drying liquid supply step (step S18) are performed in the same manner as the first drying liquid supply step (step S5) and the second drying liquid supply step (step S6) in each of the first to third embodiments. This reduces the collapse rate of the pattern on the substrate W. Furthermore, 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 reduces the surface tension acting on the pattern, further reducing the collapse rate of the pattern.

[0146] 13 is a flowchart showing a second example of the operation of the processing unit 1 according to the fourth embodiment. In the example of FIG. 13, the control unit 90 causes the processing unit 1 to perform steps S21 to S27 in accordance with a preset processing procedure (recipe). Steps S21 to S27 are similar to steps S1 to S3 and steps S5 to S8, respectively. However, at the end of step S23 (chemical liquid step: corresponding to the liquid supply step), metal is exposed on the first main surface Wa of the substrate W. According to the second example, step S24 (first drying liquid supply step) is performed after step S23. Therefore, water is not supplied to the first main surface Wa of the substrate W. This prevents a reaction between the metal and water, thereby avoiding problems caused by the reaction. Furthermore, in the second example described above, a first drying liquid supply step (step S24) and a second drying liquid supply step (step S25) are performed, similar to the first drying liquid supply step (step S5) and the second drying liquid supply step (step S6) in each of the first to third embodiments, so that the collapse rate of the pattern on the substrate W can be reduced.

[0147] Fifth Embodiment FIG. 14 is a diagram schematically illustrating an example of the configuration of a processing unit 1 according to a fifth embodiment. The processing unit 1 according to the fifth embodiment differs from the processing unit 1 according to the first embodiment in the configuration of the discharge unit 3 and the opposing member 60. In the example of FIG. 14 , the opposing member 60 includes a shielding plate 6 and a hollow shaft 61. The shielding plate 6 is provided at a position vertically opposing the first main surface Wa of the substrate W held by the substrate holder 2. In the example of FIG. 14 , the first main surface Wa of the substrate W corresponds to the upper surface, and therefore the shielding plate 6 is provided vertically above the substrate W. The shielding plate 6 has, for example, a plate-like shape and is provided with its thickness direction aligned vertically. The lower surface of the shielding plate 6 is the surface opposing the first main surface Wa of the substrate W. The shielding plate 6 has, for example, a circular shape in a plan view. The diameter of the shielding 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 even greater than the diameter of the substrate W.

[0148] In the example of Figure 14, a hollow shaft 61 is provided on the upper surface of the blocking plate 6. The hollow shaft 61 has a hollow portion, and a through-hole that passes vertically through the blocking plate 6 is formed in the center of the blocking plate 6. The hollow portion is vertically connected to the through-hole of the blocking plate 6. The nozzle 30i is provided in the hollow portion of the hollow shaft 61 and the through-hole of the blocking plate 6. The diameter of the outer peripheral surface of the nozzle 30i is smaller than the diameters of the inner peripheral surfaces of the hollow shaft 61 and the blocking plate 6. The space between the outer peripheral surface of the nozzle 30i and the inner peripheral surfaces of the hollow shaft 61 and the blocking plate 6 functions as a gas flow path 30g.

[0149] 14, the nozzle 30i is connected to the downstream end of the supply pipe 31i, and the upstream end of the supply pipe 31i is connected to the downstream ends of the supply pipes 31ia and 31ib. In this structure, when the supply valve 32ia is opened, the first drying liquid is ejected from the nozzle 30i. When the supply valve 32ib is opened, the second drying liquid is ejected from the nozzle 30i. In other words, the nozzle 30i is used in common for both the first drying liquid and the second drying liquid.

[0150] 14, nozzle 30c and nozzle 30w are provided outside opposing member 60. Also, in the example of Fig. 14, movement drive unit 35c and movement drive unit 35w are provided as movement drive unit 35. Movement drive unit 35c moves nozzle 30c between the processing position and the standby position, and movement drive unit 35w moves nozzle 30w between the processing position and the standby position.

[0151] In the example of FIG. 14 , a movement drive unit 35i is provided as the movement drive unit 35. The movement drive unit 35i moves the nozzle 30i and the opposing member 60 together. The movement drive unit 35i moves the nozzle 30i and the opposing member 60 together, for example, in the vertical direction. In this case, the movement drive unit 35i 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 30i and the shielding plate 6. The power transmission unit includes, for example, a cam mechanism or a ball screw mechanism.

[0152] The operation of the processing unit 1 according to the fifth embodiment is similar to that shown in the flowchart of Fig. 4. However, the movement driver 35i lowers the nozzle 30i and the opposing member 60 to a processing position closer to the substrate W in the first drying liquid supplying step, the second drying liquid supplying step, and the drying step, and raises them to a standby position higher than the processing position in the other steps.

[0153] In the fifth embodiment, the first drying liquid supplying step (step S5) and the second drying liquid supplying step (step S6) in each of the first to third embodiments are also performed, thereby reducing the rate of pattern collapse.

[0154] Although the substrate processing apparatus 100 and the substrate processing method have been described in detail above, the above description is merely an example in all respects, and this disclosure is not limited thereto. Furthermore, the various modifications described above can be combined and applied as long as they are not mutually inconsistent. It is understood that many modifications not illustrated can be envisioned without departing from the scope of this disclosure.

[0155] In the examples of the first to fourth embodiments, a dedicated nozzle is provided for each fluid, but similar to the nozzle 30i of the fifth embodiment, one nozzle may be shared by different types of fluids. On the other hand, in the fifth embodiment, a dedicated nozzle may be provided for each of the first drying liquid and the second drying liquid. Alternatively, one nozzle may be shared by different types of fluids.

[0156] In the above example, the substrate heating unit 4 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 unit 4 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.

[0157] bp1 First boiling point bp2 Second boiling point S1, S11, S21 Holding process (step) S4, S16, S23 Liquid supply process (step) S5, S17, S24 First drying liquid supply process (step) S6, S18, S25 Second drying liquid supply process (step) S7, S19, S26 Drying process (step) T Drying liquid supply time (second drying liquid supply time) T1 Before time T2 After time W Substrate Wa First main surface Wb Second main surface

Claims

1. A method for manufacturing a substrate, 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 first drying liquid supplying step of supplying a first drying liquid having a first boiling point and a surface tension lower than that of the processing liquid to the first main surface of the substrate after the liquid supplying step; a second drying liquid supplying step of supplying a second drying liquid having a second boiling point different from the first boiling point and a surface tension lower than that of the first drying liquid to the first main surface of the substrate after the first drying liquid supplying step; and a drying step of drying the substrate after the second drying liquid supplying step, wherein the second main surface of the substrate is heated to a first temperature during at least a portion of the first drying liquid supplying step; and at least a portion of the second main surface of the substrate is heated to a second temperature different from the first temperature during at least a portion of the second drying liquid supplying step. a positive or negative value of a value obtained by subtracting the second temperature from the first temperature is the same as a positive or negative value of a value obtained by subtracting the second boiling point from the first boiling point.

2. A substrate processing method as claimed in claim 1, wherein in the first drying liquid supplying step, a heat medium having a first medium temperature is supplied to the second main surface of the substrate, and in the second drying liquid supplying step, the heat medium having a second medium temperature is supplied to the second main surface of the substrate, and the positive and negative values ​​of the value obtained by subtracting the second medium temperature from the first medium temperature are the same as the positive and negative values ​​of the value obtained by subtracting the second boiling point from the first boiling point.

3. A substrate processing method according to claim 1 or 2, wherein the higher of the first temperature and the second temperature is equal to or higher than the lower of the first boiling point and the second boiling point.

4. A substrate processing method according to claim 1 or 2, wherein the miscibility of the processing liquid with the first drying liquid is higher than the miscibility of the processing liquid with the second drying liquid.

5. A substrate processing method as defined in claim 1 or 2, wherein in the first drying liquid supplying step, the first drying liquid is supplied to the first main surface of the substrate at a flow rate such that the temperature of the first main surface of the substrate is less than the first boiling point of the first drying liquid, while at least a portion of the second main surface of the substrate is heated to a temperature equal to or higher than the first boiling point of the first drying liquid.

6. A substrate processing method as defined in claim 1 or 2, wherein in the second drying liquid supplying step, the second drying liquid is supplied to the first main surface of the substrate at a flow rate such that the temperature of the first main surface of the substrate is less than the second boiling point of the second drying liquid, while at least a portion of the second main surface of the substrate is heated to a temperature equal to or higher than the second boiling point of the second drying liquid.

7. A substrate processing method as defined in claim 1 or claim 2, wherein the second temperature is higher than the first temperature, and in the second drying liquid supplying step, during a first period of a second drying liquid supplying time during which the second drying liquid is supplied, the temperature of the second main surface of the substrate is lower than the second temperature, and during a second period of the second drying liquid supplying time, the second main surface of the substrate is heated to the second temperature.

Images