Substrate processing method and processing solution

Abstract

To provide a substrate processing method capable of efficiently processing a substrate, and provide a substrate processing method and a processing liquid that can properly process a substrate.SOLUTION: The present invention relates to a substrate processing method and a processing liquid. An upper surface W1 of a substrate W includes a pattern formation area W1a in which a pattern P is formed and a pattern non-formation area W1b in which the pattern P is not formed. The substrate processing method includes a processing liquid supply step, a solidified film forming step, a sublimation step, and a removal step. In the processing liquid supply step, a liquid film H of a processing liquid is formed on the upper surface W1 of the substrate W. The processing liquid contains a sublimable substance and a solvent. In the solidified film forming step, the solvent is evaporated from the liquid film H to form a solidified film K containing a sublimable substance on the upper surface W1 of the substrate W. The solidified film K has a first solidified film Ka positioned over the pattern formation area W1a and a second solidified film Kb positioned over the pattern non-formation area W1b. In the sublimation step, the first solidified film Ka is sublimed. In the removal step, the second solidified film Kb is removed from the substrate W.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a substrate processing method for processing a substrate and a processing liquid used for processing the substrate. The substrate is, for example, a semiconductor wafer, a substrate for a liquid crystal display, a substrate for an organic EL (Electroluminescence), a substrate for an FPD (Flat Panel Display), a substrate for an optical display, a substrate for a magnetic disk, a substrate for an optical disk, a substrate for a magneto-optical disk, a substrate for a photomask, or a substrate for a solar cell.

Background Art

[0002] Patent Document 1 discloses a substrate processing method for processing a substrate. The substrate has a pattern formation region where a pattern is formed. A solidified film is formed in the pattern formation region. The solidified film contains a sublimable substance. The sublimable substance is, for example, tert-butanol. The solidified film includes a first portion and a second portion. Both the first portion and the second portion are located on the pattern formation region. The first portion is located above the pattern. The first portion corresponds to the surface layer portion of the solidified film. The second portion is located at the same height position as the pattern. The second portion is embedded between adjacent patterns.

[0003] The substrate drying method of Patent Document 1 includes a first sublimation step and a second sublimation step. In the first sublimation step, a first gas is supplied to the solidified film to sublime the first portion. When the first sublimation step ends, the first portion is removed from the pattern formation region, and the second portion remains in the pattern formation region. After the first sublimation step, in the second sublimation step, a second gas is supplied to the second portion to sublime the second portion. The second gas has a temperature lower than that of the first gas. When the second sublimation step ends, the second portion is removed from the pattern formation region. Therefore, when the second sublimation step ends, all of the solidified film is removed from the substrate, and the substrate is dried.

[0004] Patent Document 1 further includes a substrate heating step. The substrate heating step is performed after the first sublimation step and the second sublimation step are completed. That is, the substrate heating step is performed after the entire solidified film has sublimated. The substrate heating step involves supplying a third gas to the substrate and heating the substrate. This suppresses condensation of the gas surrounding the substrate onto the substrate.

[0005] As described above, in Patent Document 1, the first sublimation step and the second sublimation step are steps for sublimating the solidified film on the pattern formation region. The substrate heating step is not a step for sublimating the solidified film. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2014-11426 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] Even with conventional substrate processing methods, there were cases where substrates could not be processed efficiently. For example, even with conventional substrate processing methods, the solidified film did not sublimate quickly. For example, even with conventional substrate processing methods, it sometimes took a long time for the solidified film to sublimate.

[0008] Furthermore, even with conventional substrate processing methods, there were cases where the substrate could not be processed properly. For example, even with conventional substrate processing methods, the pattern formed on the surface of the substrate could collapse. For instance, when the pattern was fine, conventional substrate processing methods could not adequately suppress the collapse of the pattern.

[0009] In view of these circumstances, the present invention has been made, and its first objective is to provide a substrate processing method that can process substrates efficiently. The second objective of the present invention is to provide a substrate processing method and processing solution that can process substrates appropriately. [Means for solving the problem]

[0010] To achieve its first objective, the present invention has the following configuration. That is, the present invention is a substrate processing method for processing a substrate, wherein the substrate has an upper surface including a pattern-forming region where a pattern is formed and a pattern-non-forming region where no pattern is formed, and comprises a processing liquid supply step of supplying a processing liquid containing a sublimable substance and a solvent to the upper surface of the substrate to form a liquid film of the processing liquid on the upper surface of the substrate, a solidification film forming step of evaporating the solvent from the liquid film to form a solidification film containing the sublimable substance on the upper surface of the substrate, the solidification film having a first solidification film located on the pattern-forming region and a second solidification film located on the pattern-non-forming region, a sublimation step of blowing a first gas toward the first solidification film to sublimate the first solidification film, and a removal step of removing the second solidification film from the substrate.

[0011] The substrate has an upper surface. The upper surface includes a pattern-forming region and a non-pattern-forming region. The pattern-forming region is the portion of the upper surface of the substrate on which a pattern has been formed. The non-pattern-forming region is the portion of the upper surface of the substrate on which no pattern has been formed.

[0012] The substrate processing method processes the substrate described above. The substrate processing method comprises a processing liquid supply step and a solidification film formation step. The processing liquid supply step supplies the processing liquid to the substrate. The processing liquid contains a sublimable substance and a solvent. The processing liquid supply step forms a liquid film of the processing liquid on the upper surface of the substrate. The solidification film formation step evaporates the solvent from the liquid film. The solidification film formation step forms a solidification film on the upper surface of the substrate. The solidification film contains a sublimable substance. The solidification film has a first solidification film and a second solidification film. The first solidification film is located on the pattern formation region. The second solidification film is located on the non-pattern formation region.

[0013] The substrate processing method includes a sublimation step. The sublimation step involves blowing a first gas toward the first solidified film. The sublimation step sublimes the first solidified film. As the first solidified film sublimes, it leaves the pattern formation region. In this way, the sublimation step dries the pattern formation region while protecting the pattern formed therein.

[0014] The substrate processing method includes a removal step. The removal step removes the second solidified film from the substrate. As a result, the removal step dries the areas where the pattern is not formed.

[0015] Here, the second solidified film is located on the non-pattern formation region. In other words, the second solidified film is not located on the pattern formation region. Therefore, even if the removal of the second solidified film is accelerated, there is no risk of the pattern collapsing. Thus, the removal process can efficiently remove the second solidified film from the substrate.

[0016] In summary, the substrate processing method includes a sublimation step and a removal step. The sublimation step sublimes the first solidified film. The removal step removes the second solidified film. Thus, the sublimation step does not require the sublimation of the second solidified film. The removal step can efficiently remove the second solidified film from the substrate. Therefore, the substrate is efficiently dried by both the sublimation step and the removal step. Consequently, the substrate processing method can process the substrate efficiently.

[0017] In the substrate processing method described above, it is preferable that the removal step begins after the sublimation step is completed. Therefore, the removal step is not performed until the sublimation step is completed. Consequently, the removal step is not performed until the drying of the pattern formation region is completed. Therefore, the pattern formed in the pattern formation region can be protected more effectively.

[0018] In the substrate processing method described above, it is preferable that the period during which the removal step is performed overlaps with at least a portion of the period during which the sublimation step is performed. This allows for a reduction in the total time required for both the sublimation and removal steps. As a result, the substrate can be processed more efficiently.

[0019] In the substrate processing method described above, it is preferable that the removal step begins after the sublimation step has started. Therefore, the sublimation step starts before the removal step. Consequently, drying of the pattern formation region begins before the removal step. Thus, the pattern formed in the pattern formation region can be adequately protected.

[0020] In the substrate processing method described above, the removal step preferably involves changing the second solidified film into a gas phase. By changing the second solidified film into a gas phase, the second solidified film can be suitably removed from the substrate. Here, the removal step may change the second solidified film into a gas phase without passing through the liquid phase. Alternatively, the removal step may change the second solidified film into a gas phase via the liquid phase.

[0021] Furthermore, during the removal process, the second solidified film may temporarily turn into a liquid before it turns into a gas. As described above, the second solidified film is located on the non-pattern formation region. The second solidified film is not located on the pattern formation region. Therefore, even if the second solidified film temporarily turns into a liquid, that liquid will not reach the pattern formation region. Thus, even if the second solidified film temporarily turns into a liquid, the pattern formed in the pattern formation region can be adequately protected.

[0022] In the substrate processing method described above, the removal step preferably involves vaporizing the second solidified film. By vaporizing the second solidified film, the second solidified film can be suitably removed from the substrate.

[0023] In the substrate processing method described above, the removal step preferably involves blowing a second gas toward the second solidified film. The second gas can suitably convert the second solidified film into a gas phase. Therefore, the removal step can suitably remove the second solidified film from the substrate.

[0024] In the above substrate processing method, it is preferable that the flow rate of the second gas is larger than the flow rate of the first gas. The second gas can efficiently convert the second solidified film into the gas phase. Therefore, the removal step can efficiently remove the second solidified film from the substrate. In other words, the removal of the second solidified film can be preferably promoted. For example, the time required for the removal step can be shortened.

[0025] In the above substrate processing method, it is preferable that in the removal step, the second gas heats the second solidified film. The second gas can more efficiently convert the second solidified film into the gas phase. Therefore, the removal step can more efficiently remove the second solidified film from the substrate. In other words, the removal of the second solidified film can be preferably promoted.

[0026] In the above substrate processing method, it is preferable that the second gas has a temperature higher than the temperature of the first gas. The second gas can preferably heat the second solidified film. Therefore, the removal of the second solidified film can be preferably promoted.

[0027] In the above substrate processing method, it is preferable that the second gas has a temperature higher than the melting point of the sublimable substance. The second gas can more efficiently convert the second solidified film into the gas phase. In addition, even if the second solidified film temporarily changes into a liquid, the pattern formed in the pattern formation region can be preferably protected.

[0028] In the above substrate processing method, it is preferable that the second gas has a temperature higher than the melting point of the second solidified film. The second gas can more efficiently convert the second solidified film into the gas phase. In addition, even if the second solidified film temporarily changes into a liquid, the pattern formed in the pattern formation region can be preferably protected.

[0029] In the above substrate processing method, it is preferable that in the removal step, the second solidified film is heated. The removal step can more efficiently remove the second solidified film from the substrate.

[0030] In the substrate processing method described above, the removal step preferably involves heating the pattern-free region and heating the second solidified film through the pattern-free region. As described above, the second solidified film is located on the pattern-free region. Therefore, the pattern-free region is in contact with the second solidified film. Thus, by heating the pattern-free region, the second solidified film can be suitably heated through the pattern-free region.

[0031] In the substrate processing method described above, the removal step preferably involves heating the pattern-free region to a temperature higher than the temperature of the first gas. This allows for suitable heating of the second solidified film. Therefore, the drying of the pattern-free region can be effectively promoted.

[0032] In the substrate processing method described above, the removal step preferably involves heating the lower surface of the substrate. This allows for suitable heating of areas where patterns are not formed.

[0033] In the substrate processing method described above, the removal step preferably involves heating the second solidified film with at least one of a high-temperature fluid, a resistance heater, and a lamp heater. This allows for suitable heating of the second solidified film.

[0034] In the substrate processing method described above, the vapor pressure of the sublimable substance at room temperature is preferably 100 Pa or less. When the vapor pressure of the sublimable substance is 100 Pa or less, the vapor pressure of the sublimable substance is relatively low. The inventors have found that when the vapor pressure of the sublimable substance is relatively low, the second solidified film is less likely to sublimate than the first solidified film. As described above, the substrate processing method includes a removal step in addition to the sublimation step. Therefore, even when the second solidified film is less likely to sublimate, the substrate processing method can suitably remove the second solidified film from the substrate. Consequently, even when the vapor pressure of the sublimable substance is 100 Pa or less, this substrate processing method can process the substrate efficiently. In other words, when the vapor pressure of the sublimable substance is 100 Pa or less, this substrate processing method exhibits a very significant effect.

[0035] In the substrate processing method described above, it is preferable that the sublimable substance includes at least one of pinacolin oxime, acetophenone oxime, cyclopentanone oxime, and 4-tert-butylphenol. This allows for proper processing of the substrate. In other words, the substrate processing method described above can achieve a second objective in addition to the first objective.

[0036] Specifically, when the sublimable substance contains pinacolin oxime, the above-described substrate processing method can properly process the substrate. Here, the inventors have found the following: Fa1) Fa2). Fa1) Pinacoline oxime has the property of being sublimable while protecting the substrate pattern. Fa2) Based on the attributes described in Fa1) above, pinacolin oxime is suitable for use in substrate processing methods and processing solutions.

[0037] When the sublimable substance contains acetophenone oxime, the above-described substrate treatment method can appropriately treat the substrate. Here, the inventors have found the following Fb1) and Fb2). Fb1) Acetophenone oxime has the property of being sublimable while protecting the substrate pattern. Fb2) Based on the attributes described in Fb1) above, acetophenone oxime is suitable for use in substrate processing methods and processing solutions.

[0038] When the sublimable substance contains cyclopentanone oxime, the above-described substrate treatment method can appropriately treat the substrate. Here, the inventors have found the following Fc1) and Fc2). Fc1) Cyclopentanone oxime has the property of being sublimable while protecting the substrate pattern. Fc2) Based on the attributes described in Fc1) above, cyclopentanone oxime is suitable for use in substrate processing methods and processing solutions.

[0039] When the sublimable substance contains 4-tert-butylphenol, the above-described substrate treatment method can appropriately treat the substrate. Here, the inventors have found the following Fd1) and Fd2). Fd1)4-tertbutylphenol has the property of being sublimable while protecting the pattern on the substrate. Fd2) Based on the attributes described in Fd1) above, 4-tert-butylphenol is suitable for use in substrate processing methods and processing solutions.

[0040] To achieve a second objective, the present invention has the following configuration. That is, the present invention is a substrate processing method for processing a patterned substrate, comprising: a processing liquid supply step of supplying a processing liquid containing a sublimable substance and a solvent to the substrate; a solidification film formation step of evaporating the solvent from the processing liquid on the substrate to form a solidified film containing the sublimable substance on the substrate; and a sublimation step of sublimating the solidified film, wherein the sublimable substance comprises at least one of pinacolin oxime, acetophenone oxime, cyclopentanone oxime, and 4-tert-butylphenol.

[0041] The substrate processing method processes a substrate on which a pattern has been formed. Specifically, the substrate processing method comprises a processing liquid supply step, a solidification film formation step, and a sublimation step. The processing liquid supply step supplies a processing liquid to the substrate. The processing liquid contains a sublimable substance and a solvent. The solidification film formation step evaporates the solvent from the processing liquid on the substrate. The solidification film formation step forms a solidified film on the substrate. The solidified film contains a sublimable substance. The sublimation step sublimes the solidified film.

[0042] The sublimable substance includes at least one of pinacolin oxime, acetophenone oxime, cyclopentanone oxime, and 4-tert-butylphenol. Therefore, the substrate processing method can properly process the substrate. Specifically, the substrate processing method can properly process the substrate while protecting the pattern formed on the substrate.

[0043] To achieve a second objective, the present invention has the following configuration. That is, the present invention is a processing solution used for processing a patterned substrate, wherein the processing solution comprises a sublimable substance and a solvent, and the sublimable substance comprises at least one of pinacolin oxime, acetophenone oxime, cyclopentanone oxime, and 4-tert-butylphenol.

[0044] The processing solution is used for processing the substrate on which the pattern has been formed. Specifically, the processing solution is a processing solution for substrate processing. Specifically, the processing solution is a processing solution for drying the substrate.

[0045] The processing solution contains a sublimable substance and a solvent. The sublimable substance includes at least one of pinacolin oxime, acetophenone oxime, cyclopentanone oxime, and 4-tert-butylphenol. Therefore, the substrate can be properly processed using the processing solution. Specifically, by using the processing solution, the substrate can be properly processed while protecting the pattern formed on the substrate.

[0046] In the processing solution described above, the solvent is preferably isopropyl alcohol. The substrate can be processed more effectively using the processing solution. [Effects of the Invention]

[0047] According to the substrate processing method of the present invention, substrates can be processed efficiently. According to the substrate processing method and processing solution of the present invention, substrates can be processed appropriately. [Brief explanation of the drawing]

[0048] [Figure 1] This is a plan view showing the inside of the substrate processing apparatus of the first embodiment. [Figure 2] This is a control block diagram of a substrate processing unit. [Figure 3] This figure shows the configuration of the processing unit and processing liquid generation unit according to the first embodiment. [Figure 4] This is a flowchart showing the procedure for the substrate processing method of the first embodiment. [Figure 5] This diagram schematically shows the substrate during the processing liquid supply process. [Figure 6] This diagram schematically shows the substrate during the solidification film formation process. [Figure 7] This diagram schematically shows the substrate during the solidification film formation process. [Figure 8] This diagram schematically shows the substrate during the sublimation process. [Figure 9] This diagram schematically shows the substrate during the sublimation process. [Figure 10] This table shows the evaluation of each substrate treated according to Experimental Examples 1-4. [Figure 11] This is a cross-sectional view of the circuit board. [Figure 12] This is a plan view of the circuit board. [Figure 13] This figure shows the configuration of the processing unit and processing liquid generation unit according to the second embodiment. [Figure 14] This is a flowchart showing the procedure for the substrate processing method of the second embodiment. [Figure 15] This diagram schematically shows the substrate during the processing liquid supply process. [Figure 16] This diagram schematically shows the substrate during the solidification film formation process. [Figure 17] This diagram schematically shows the substrate during the sublimation process. [Figure 18] This diagram schematically shows the substrate during the sublimation process. [Figure 19] This diagram schematically shows the substrate during the removal process. [Figure 20] This diagram schematically shows the substrate during the removal process. [Figure 21] This figure shows the configuration of the processing unit and processing liquid generation unit according to the third embodiment. [Figure 22] This diagram schematically shows the substrate during the removal process. [Figure 23] This diagram schematically shows the substrate during the removal process. [Figure 24]This figure shows the configuration of the processing unit and processing liquid generation unit in a modified embodiment. [Figure 25] This figure shows the configuration of the processing unit and processing liquid generation unit in a modified embodiment. [Figure 26] This flowchart shows the procedure for the substrate processing method of the modified embodiment. [Figure 27] This table shows the evaluation of each substrate treated in Experimental Examples 5a and 5b and Comparative Examples 1a, 1b, 2a, and 2b. [Figure 28] This table shows the evaluation of each substrate treated in Comparative Examples 3a, 3b, 4a, 4b, 5a, 6a, and 7a. [Figure 29] This is a schematic enlarged view showing the substrate during the solidification film formation process. [Figure 30] This graph shows the relationship between angle and average collapse rate. [Figure 31] This is a diagram illustrating the mechanism of pattern collapse. [Figure 32] This is a diagram illustrating the mechanism of pattern collapse. [Figure 33] This is a diagram illustrating the mechanism of pattern collapse. [Figure 34] This is a diagram illustrating the mechanism of pattern collapse. [Figure 35] This is a diagram illustrating the pattern protection mechanism. [Figure 36] This is a diagram illustrating the pattern protection mechanism. [Figure 37] This is a diagram illustrating the pattern protection mechanism. [Figure 38] This is a diagram illustrating the pattern protection mechanism. [Modes for carrying out the invention]

[0049] The substrate processing method and processing solution of the present invention will be described below with reference to the drawings.

[0050] <1. First Embodiment> <1-1. Overview of Substrate Processing Equipment> Figure 1 is a plan view showing the interior of the substrate processing apparatus 1 of the first embodiment. The substrate processing apparatus 1 processes the substrate W. The processing includes a drying process.

[0051] The substrate W is, for example, a semiconductor wafer, a substrate for liquid crystal displays, an organic electroluminescence (EL) substrate, a flat panel display (FPD) substrate, an optical display substrate, a magnetic disk substrate, an optical disk substrate, a magneto-optical disk substrate, a photomask substrate, or a solar cell substrate. The substrate W has a thin, flat shape. The substrate W has a roughly circular shape in plan view.

[0052] The substrate processing apparatus 1 comprises an indexer unit 3 and a processing block 7. The processing block 7 is connected to the indexer unit 3. The indexer unit 3 supplies the substrate W to the processing block 7. The processing block 7 performs processing on the substrate W. The indexer unit 3 retrieves the substrate W from the processing block 7.

[0053] In this specification, for convenience, the direction in which the indexer unit 3 and the processing block 7 are aligned is called the "front-to-back direction X". The front-to-back direction X is horizontal. Within the front-to-back direction X, the direction from the processing block 7 toward the indexer unit 3 is called "forward". The direction opposite to forward is called "backward". The horizontal direction perpendicular to the front-to-back direction X is called the "width direction Y". One direction of the "width direction Y" is appropriately called "right". The direction opposite to right is called "left". The direction perpendicular to the horizontal is called the "vertical direction Z". In each figure, front, back, right, left, up, and down are shown as appropriate for reference.

[0054] The indexer unit 3 includes a plurality (for example, four) of carrier mounting units 4. Each carrier mounting unit 4 mounts one carrier C. The carrier C accommodates multiple substrates W. The carrier C is, for example, a FOUP (Front Opening Unified Pod), SMIF (Standard Mechanical Interface), or OC (Open Cassette).

[0055] The indexer unit 3 includes a transport mechanism 5. The transport mechanism 5 is located behind the carrier mounting unit 4. The transport mechanism 5 transports the substrate W. The transport mechanism 5 has access to the carrier C which is placed on the carrier mounting unit 4. The transport mechanism 5 includes a hand 5a and a hand drive unit 5b. The hand 5a supports the substrate W. The hand drive unit 5b is connected to the hand 5a. The hand drive unit 5b moves the hand 5a. The hand drive unit 5b moves the hand 5a, for example, in the forward / backward direction X, the width direction Y, and the vertical direction Z. The hand drive unit 5b rotates the hand 5a, for example, in a horizontal plane.

[0056] The processing block 7 includes a transport mechanism 8. The transport mechanism 8 transports the substrate W. The transport mechanism 8 and the transport mechanism 5 can transfer the substrate W to each other. The transport mechanism 8 includes a hand 8a and a hand drive unit 8b. The hand 8a supports the substrate W. The hand drive unit 8b is connected to the hand 8a. The hand drive unit 8b moves the hand 8a. The hand drive unit 8b moves the hand 8a, for example, in the forward / backward direction X, the width direction Y, and the vertical direction Z. The hand drive unit 8b rotates the hand 8a, for example, in a horizontal plane.

[0057] The processing block 7 comprises a plurality of processing units 11. The processing units 11 are arranged to the side of the transport mechanism 8. Each processing unit 11 performs processing on the substrate W.

[0058] The processing unit 11 includes a substrate holding section 13. The substrate holding section 13 holds the substrate W.

[0059] The transport mechanism 8 can access each processing unit 11. The transport mechanism 8 can transfer the substrate W to the substrate holding unit 13. The transport mechanism 8 can take the substrate W from the substrate holding unit 13.

[0060] Figure 2 is a control block diagram of the substrate processing apparatus 1. The substrate processing apparatus 1 includes a control unit 10. The control unit 10 controls the transport mechanisms 5 and 8 and the processing unit 11.

[0061] The control unit 10 is implemented by a central processing unit (CPU) that executes various processes, RAM (Random-Access Memory) which serves as a workspace for calculations, and a storage medium such as a fixed disk. The control unit 10 has various types of information that are pre-stored in the storage medium. For example, the information held by the control unit 10 is transport information for controlling the transport mechanisms 5 and 8. For example, the information held by the control unit 10 is processing information for controlling the processing unit 11. Processing information is also called a processing recipe.

[0062] A brief explanation of the operation of the substrate processing device 1 will be given.

[0063] The indexer unit 3 supplies the substrate W to the processing block 7. Specifically, the transport mechanism 5 transfers the substrate W from the carrier C to the transport mechanism 8 of the processing block 7.

[0064] The processing block 7 distributes the substrates W from the indexer unit 3 to the processing units 11. Specifically, the transport mechanism 8 transports the substrates W from the transport mechanism 5 to the substrate holding units 13 of each processing unit 11.

[0065] The processing unit 11 processes the substrate W held in the substrate holding section 13. For example, the processing unit 11 performs a drying process on the substrate W.

[0066] After the processing unit 11 has processed the substrate W, the processing block 7 returns the substrate W from the processing unit 11 to the indexer unit 3. Specifically, the transport mechanism 8 transports the substrate W from the substrate holding unit 13 to the transport mechanism 5.

[0067] The indexer unit 3 retrieves the substrate W from the processing block 7. Specifically, the transport mechanism 5 transports the substrate W from the transport mechanism 8 to the carrier C.

[0068] <1-2. Configuration of Processing Unit 11> Figure 3 shows the configuration of the processing unit 11. Each processing unit 11 has the same structure. The processing units 11 are classified as single-wafer type. That is, each processing unit 11 processes only one substrate W at a time.

[0069] The processing unit 11 includes a housing 12. The housing 12 has a roughly box-like shape. The substrate W is processed inside the housing 12.

[0070] In the first embodiment, the inside of the housing 12 is kept at room temperature. The inside of the housing 12 is kept at atmospheric pressure. Therefore, the substrate W is processed in an environment of room temperature and atmospheric pressure. Here, room temperature includes room temperature. Room temperature is, for example, a temperature in the range of 5°C or higher and 35°C or lower. Room temperature is, for example, a temperature in the range of 10°C or higher and 30°C or lower. Room temperature is, for example, a temperature in the range of 20°C or higher and 25°C or lower. Atmospheric pressure includes standard atmospheric pressure (1 atmosphere, 101325 Pa). Atmospheric pressure is, for example, an atmosphere in the range of 0.7 atmospheres or higher and 1.3 atmospheres or lower. In this specification, pressure is expressed as absolute pressure with respect to absolute vacuum.

[0071] The aforementioned substrate holder 13 is installed inside the housing 12. The substrate holder 13 holds one substrate W. The substrate holder 13 holds the substrate W in a substantially horizontal position. The substrate holder 13 holds, for example, the bottom surface of the substrate W and at least one of the edges of the substrate W.

[0072] The processing unit 11 includes a rotary drive unit 14. At least a portion of the rotary drive unit 14 is installed inside the housing 12. The rotary drive unit 14 is connected to the substrate holder 13. The rotary drive unit 14 rotates the substrate holder 13. The substrate W held by the substrate holder 13 rotates together with the substrate holder 13. The substrate W held by the substrate holder 13 rotates around the axis of rotation B. The axis of rotation B passes through the center of the substrate W and extends vertically in the direction Z.

[0073] The processing unit 11 includes one or more (for example, five) supply units 15a, 15b, 15c, 15d, and 15e. Each of the supply units 15a-15e supplies a liquid or gas to the substrate W. More specifically, each of the supply units 15a-15e supplies a liquid or gas to the substrate W held by the substrate holding unit 13. Each of the supply units 15a-15e supplies a liquid or gas to the upper surface W1 of the substrate W held by the substrate holding unit 13.

[0074] Specifically, the supply unit 15a supplies the processing liquid. The processing liquid contains a sublimable substance and a solvent.

[0075] As described above, the inside of the enclosure 12 is at room temperature and atmospheric pressure. Therefore, the processing liquid is used in a room temperature environment. The processing liquid is used in an atmospheric pressure environment.

[0076] The supply unit 15b supplies a chemical solution. The chemical solution is, for example, an etching solution. The chemical solution includes, for example, at least one of hydrofluoric acid (HF) and buffered hydrofluoric acid (BHF).

[0077] The supply unit 15c supplies the rinse solution. The rinse solution is, for example, deionized water (DIW).

[0078] The supply unit 15d supplies the displacement liquid. The displacement liquid is, for example, an organic solvent. The displacement liquid is, for example, isopropyl alcohol (IPA).

[0079] The supply unit 15e supplies a first gas. The first gas is, for example, a dry gas. The dry gas has a dew point lower than room temperature. The dew point is, for example, about -76°C. Therefore, the dry gas does not condense at room temperature. The first gas is, for example, air. The first gas is, for example, compressed air. The first gas is, for example, an inert gas. The first gas is, for example, nitrogen gas.

[0080] The supply unit 15a is equipped with a nozzle 16a. Similarly, the supply units 15b-15e are each equipped with nozzles 16b-16e. The nozzles 16a-16e are each installed inside the housing 12. Nozzle 16a discharges the processing liquid. Nozzle 16b discharges the chemical solution. Nozzle 16c discharges the rinsing solution. Nozzle 16d discharges the replacement solution. Nozzle 16e discharges the first gas. Nozzle 16e blows out the first gas.

[0081] Nozzles 16a-16e are each movable to a processing position and a standby position. The processing position is, for example, a position above the substrate W held by the substrate holder 13. The processing position is, for example, a position above the center of the substrate W held by the substrate holder 13. The center of the substrate W intersects with the rotation axis B. The standby position is, for example, a position away from above the substrate W held by the substrate holder 13.

[0082] The supply unit 15a includes a pipe 17a, which is connected to the nozzle 16a. Similarly, the supply units 15b-15e each include a pipe 17b-17e, which are connected to the nozzles 16b-16e, respectively.

[0083] The supply unit 15a is equipped with a valve 18a. The valve 18a is installed in the piping 17a. When valve 18a is open, the nozzle 16a discharges the processing liquid. When valve 18b is closed, the nozzle 16a does not discharge the processing liquid. Similarly, the supply units 15b-15e are each equipped with valves 18b-18e. The valves 18b-18e are each installed in the piping 17b-17e. The valves 18b-18e control the supply of the chemical solution, rinsing liquid, displacement liquid, and first gas, respectively.

[0084] At least a portion of the piping 17a may be provided outside the housing 12. The piping 17b-17e may be arranged in the same manner as piping 17a. The valve 18a may be provided outside the housing 12. The valves 18b-18e may be arranged in the same manner as valve 18a.

[0085] The substrate processing apparatus 1 includes a processing liquid generation unit 20. The processing liquid generation unit 20 generates a processing liquid.

[0086] The processing liquid generation unit 20 is located outside the housing 12. The processing liquid generation unit 20 is connected to the supply unit 15a. The processing liquid generation unit 20 is connected, for example, to piping 17a. The processing liquid generation unit 20 supplies the processing liquid to the supply unit 15a.

[0087] The supply unit 15b is connected in communication with the chemical solution supply source 19b. The chemical solution supply source 19b is connected, for example, to piping 17b. The chemical solution supply source 19b delivers the chemical solution to the supply unit 15b.

[0088] The supply unit 15c is connected in communication with the rinse liquid supply source 19c. The rinse liquid supply source 19c is connected, for example, to the piping 17c. The rinse liquid supply source 19c supplies rinse liquid to the supply unit 15c.

[0089] The supply unit 15d is connected in communication with the replacement fluid supply source 19d. The replacement fluid supply source 19d is connected, for example, to piping 17d. The replacement fluid supply source 19d sends replacement fluid to the supply unit 15d.

[0090] The supply unit 15e is connected in communication with the first gas supply source 19e. The first gas supply source 19e is connected, for example, to piping 17e. The first gas supply source 19e supplies the first gas to the supply unit 15e.

[0091] Here, the processing liquid generation unit 20 may supply processing liquid to multiple processing units 11. Alternatively, the processing liquid generation unit 20 may supply processing liquid to only one processing unit 11. The same applies to the chemical liquid supply source 19b, the rinse liquid supply source 19c, the displacement liquid supply source 19d, and the first gas supply source 19e.

[0092] The chemical solution supply source 19b may be an element of the substrate processing apparatus 1. For example, the chemical solution supply source 19b may be a chemical solution tank included in the substrate processing apparatus 1. Alternatively, the chemical solution supply source 19b may not be an element of the substrate processing apparatus 1. For example, the chemical solution supply source 19b may be a utility facility installed outside the substrate processing apparatus 1. Similarly, the rinse solution supply source 19c, the displacement solution supply source 19d, and the first gas supply source 19e may each be an element of the substrate processing apparatus 1 or may not be an element of the substrate processing apparatus 1.

[0093] The processing unit 11 may further include a cup (not shown). The cup is installed inside the housing 12. The cup is positioned around the substrate holder 13. The cup catches any liquid splashed from the substrate W held by the substrate holder 13.

[0094] Refer to Figure 2. The control unit 10 controls the rotary drive unit 14 and the valves 18a-18e.

[0095] <1-3. Treatment solution> The processing liquid generated by the processing liquid generation unit 20 is described below. The processing liquid contains a sublimable substance and a solvent. For example, the processing liquid consists only of a sublimable substance and a solvent.

[0096] Sublimable substances possess the property of sublimation. "Sublimation" refers to the characteristic of a substance, compound, or mixture to undergo a phase transition from solid to gas, or from gas to solid, without passing through a liquid phase.

[0097] The sublimable substance includes, for example, at least one of the following compounds a, b, c, and d. Compound a: pinacolin oxime Compound b: Acetophenone oxime Compound c: Cyclopentanone oxime Compound d: 4-tertbutylphenol

[0098] For example, a sublimable substance consists of at least one of compounds a, b, c, and d. In other words, a sublimable substance is one of compounds a, b, c, and d.

[0099] For example, a sublimable substance consists of two or more compounds a, b, c, and d. For example, a sublimable substance consists of any two of compounds a, b, c, and d. For example, a sublimable substance consists of any three of compounds a, b, c, and d. For example, a sublimable substance consists of compounds a, b, c, and d.

[0100] The solvent is a liquid at room temperature. The solvent dissolves sublimable substances. Therefore, the sublimable substances in the treatment solution are dissolved in the solvent. In other words, the treatment solution contains the solvent and the sublimable substances dissolved in the solvent. The sublimable substances correspond to the solute in the treatment solution.

[0101] The solvent has a relatively high vapor pressure at room temperature. For example, it is preferable that the vapor pressure of the solvent at room temperature is higher than the vapor pressure of the sublimable substance at room temperature.

[0102] The solvent is, for example, an organic solvent. The solvent is, for example, an alcohol.

[0103] The solvent includes, for example, at least one of the following compounds e1-e10. Compound e1: Isopropyl alcohol (IPA) Compound e2: Acetone Compound e3: methanol Compound e4: Ethanol Compound e5: tert-butanol Compound e6: 1-propanol Compound e7: Isobutanol Compound e8: 1-Ethoxy-2-propanol Compound e9: 1-butanol Compound e10: Propylene glycol monomethyl ether acetate

[0104] The volume of sublimable substance contained in the processing solution is smaller than the volume of solvent contained in the processing solution. For example, the volume ratio RV of sublimable substance to solvent is preferably 1 [Vol%] or more and 20 [Vol%]. Here, the volume ratio RV is defined by the following formula. RV = (Volume of sublimable substance in the treatment solution) / (Volume of solvent in the treatment solution) * 100 [Vol%]

[0105] <1-4. Configuration of the processing liquid generation unit 20> Refer to Figure 3. The processing liquid generation unit 20 generates the processing liquid.

[0106] The processing liquid generation unit 20 includes a tank 21. The tank 21 is connected to the supply unit 15a. The tank 21 is connected to the nozzle 16a. In the first embodiment, the processing liquid generation unit 20 generates the processing liquid in the tank 21. The processing liquid is generated in an environment at room temperature. The processing liquid is generated in an environment at normal pressure.

[0107] The processing liquid generation unit 20 stores the generated processing liquid in the tank 21. The processing liquid is stored under normal temperature conditions. The processing liquid is stored under normal pressure conditions.

[0108] The processing liquid generation unit 20 includes a supply unit 23 and a supply unit 25. The supply unit 23 supplies a sublimable substance to the tank 21. The supply unit 25 supplies a solvent to the tank 21. The sublimable substance and the solvent are mixed in the tank 21. This generates a processing liquid containing the sublimable substance and the solvent.

[0109] The supply unit 23 is connected to the tank 21. The supply unit 23 is further connected to the sublimable substance supply source 24. The sublimable substance supply source 24 supplies the sublimable substance to the supply unit 23.

[0110] The supply unit 23 includes, for example, a pipe 23a and a valve 23b. The pipe 23a has a first end connected to the tank 21 and a second end connected to the sublimable substance supply source 24. The valve 23b is provided on the pipe 23a. When the valve 23b is open, the supply unit 23 supplies the sublimable substance to the tank 21. When the valve 23b is closed, the supply unit 23 does not supply the sublimable substance to the tank 21.

[0111] The supply unit 25 is connected to the tank 21. The supply unit 25 is further connected to the solvent supply source 26. The solvent supply source 26 supplies solvent to the supply unit 25.

[0112] The supply unit 25 includes, for example, a pipe 25a and a valve 25b. The pipe 25a has a first end connected to the tank 21 and a second end connected to the solvent supply source 26. The valve 25b is provided on the pipe 25a. When the valve 25b is open, the supply unit 25 supplies solvent to the tank 21. When the valve 25b is closed, the supply unit 25 does not supply solvent to the tank 21.

[0113] The processing liquid generation unit 20 includes at least one (e.g., two) first sensors 29. The first sensors 29 detect the amount of processing liquid stored in the tank 21. The first sensors 29 are, for example, attached to the tank 21. The first sensors 29 detect the height of the liquid level of the processing liquid stored in the tank 21. The first sensors 29 are, for example, liquid level sensors.

[0114] The processing liquid generation unit 20 includes a liquid supply unit 31. The liquid supply unit 31 sends the processing liquid from the tank 21 to the supply unit 15a.

[0115] The liquid supply unit 31 includes, for example, piping 32, a pump 33, a filter 34, and a fitting 35. Piping 32 is connected to the tank 21. The pump 33 is installed on piping 32. The filter 34 is installed on piping 32. The fitting 35 is connected to piping 32. The fitting 35 is further connected to piping 17a. Piping 32 and piping 17a are connected to each other by the fitting 35.

[0116] Pump 33 sends the processing liquid from the tank 21 to the pipe 17a through the pipe 17a and fittings 35. This allows pump 33 to send the processing liquid from the tank 21 to the supply unit 15a. Filter 34 filters the processing liquid flowing through the pipe 17a. Filter 34 removes foreign matter from the processing liquid.

[0117] Refer to Figure 2. The control unit 10 controls the processing liquid generation unit 20. The control unit 10 is electrically connected to the processing liquid generation unit 20 in a communication manner.

[0118] The control unit 10 controls the supply unit 23, the supply unit 25, and the liquid delivery unit 31. The control unit 10 also controls the valve 23b, the valve 25b, and the pump 33.

[0119] The control unit 10 acquires the detection result of the first sensor 29.

[0120] The control unit 10 has processing liquid generation information for controlling the processing liquid generation unit 20. The processing liquid generation information is pre-stored in the storage medium of the control unit 10.

[0121] <1-5. Examples of operation of the processing liquid generation unit 20 and the processing unit 11> Figure 4 is a flowchart showing the procedure of the substrate processing method according to the first embodiment. The substrate processing method comprises steps S1 and S11-S18. Step S1 is performed by the processing liquid generation unit 20. Steps S11-S18 are substantially performed by the processing unit 11. Step S1 is performed in parallel with steps S11-S18. The processing liquid generation unit 20 and the processing unit 11 operate according to the control of the control unit 10.

[0122] Step S1: Process liquid generation process The processing liquid generation unit 20 generates the processing liquid. Specifically, the supply unit 23 supplies a sublimable substance to the tank 21. The supply unit 25 supplies a solvent to the tank 21. As a result, the processing liquid is generated in the tank 21. The processing liquid is then stored in the tank 21.

[0123] The first sensor 29 detects the amount of processing liquid stored in the tank 21. The control unit 10 monitors the detection result of the first sensor 29.

[0124] The control unit 10 starts and stops the processing liquid generation process based on the detection result of the first sensor 29. For example, when the amount of processing liquid stored in the tank 21 is less than a first threshold, the control unit 10 starts the processing liquid generation process. As a result, the processing liquid generation unit 20 starts generating the processing liquid. Consequently, the amount of processing liquid stored in the tank 21 increases. For example, when the amount of processing liquid stored in the tank 21 is greater than a second threshold, the control unit 10 stops the processing liquid generation process. The second threshold is greater than the first threshold. As a result, the processing liquid generation unit 20 stops generating the processing liquid. Consequently, the increase in the amount of processing liquid stored in the tank 21 stops. The first and second thresholds are, for example, preset. The first and second thresholds are defined, for example, in the processing liquid generation information.

[0125] Step S11: Rotation start process The substrate holder 13 holds the substrate W. The substrate W is held in a substantially horizontal position. The rotation drive unit 14 starts rotating the substrate holder 13. The substrate W held by the substrate holder 13 starts to rotate. Steps S12-S17 are performed with the substrate W in a rotated state.

[0126] Step S12: Chemical solution supply process The supply unit 15b supplies the chemical solution to the substrate W. Specifically, valve 18b opens. Nozzle 16b discharges the chemical solution. The chemical solution is supplied to the upper surface W1 of the substrate W. For example, the chemical solution etches the substrate W. For example, the chemical solution removes the native oxide film from the substrate W. Then, the supply unit 15b stops supplying the chemical solution to the substrate W. Specifically, valve 18b closes. Nozzle 16b stops discharging the chemical solution.

[0127] Step S13: Rinse fluid supply process The supply unit 15c supplies rinsing liquid to the substrate W. Specifically, the valve 18c opens. The nozzle 16c discharges the rinsing liquid. The rinsing liquid is supplied to the upper surface W1 of the substrate W. For example, the substrate W is cleaned with the rinsing liquid. For example, the chemical solution is removed from the substrate W with the rinsing liquid. Then, the supply unit 15c stops supplying rinsing liquid to the substrate W. Specifically, the valve 18c closes. The nozzle 16c stops discharging the rinsing liquid.

[0128] Step S14: Replacement fluid supply process The supply unit 15d supplies replacement liquid to the substrate W. Specifically, the valve 18d opens. The nozzle 16d discharges the replacement liquid. The replacement liquid is supplied to the upper surface W1 of the substrate W. The replacement liquid removes the rinse liquid from the substrate W. This replaces the rinse liquid on the substrate W with the replacement liquid. Then, the supply unit 15d stops supplying replacement liquid to the substrate W. Specifically, the valve 18d closes. The nozzle 16d stops discharging the replacement liquid.

[0129] Step S15: Processing liquid supply process The processing liquid generation unit 20 sends the processing liquid generated by the processing liquid generation process to the supply unit 15a. Specifically, the pump 33 sends the processing liquid from the tank 21 to the supply unit 15a. The supply unit 15a supplies the processing liquid to the substrate W. The supply unit 15a supplies the processing liquid to the upper surface W1 of the substrate W. Specifically, the valve 18a opens. The nozzle 16a discharges the processing liquid. The processing liquid is supplied to the upper surface W1 of the substrate W. The processing liquid removes the replacement liquid from the substrate W. This replaces the replacement liquid on the substrate W with the processing liquid. Then, the processing liquid generation unit 20 stops supplying the processing liquid to the supply unit 15a. Specifically, the pump 33 stops. The supply unit 15a stops supplying the processing liquid to the substrate W. Specifically, the valve 18a closes. The nozzle 16a stops discharging the processing liquid.

[0130] Figure 5 is a schematic diagram showing the substrate W in the processing liquid supply process. The substrate W has a pattern P. The pattern P is formed on the surface of the substrate W. When the substrate W is held by the substrate holder 13, the pattern P is located on the upper surface W1 of the substrate W. When the substrate W is held by the substrate holder 13, the pattern P faces upward.

[0131] The pattern P may be formed on the substrate W before the processing unit 11 processes the substrate W. The pattern P may also be formed on the substrate W by, for example, a chemical supply step (step S12).

[0132] Pattern P has a protrusion W2 and a recess A. The protrusion W2 is part of the substrate W. The protrusion W2 is a structure. The protrusion W2 is composed of, for example, a silicon oxide film (SiO2), a silicon nitride film (SiN), or a polysilicon film. The protrusion W2 rises upward. The recess A is adjacent to the side of the protrusion W2. The recess A is a space. The recess A is open upward. The protrusion W2 corresponds to a wall that demarcates the recess A.

[0133] The processing liquid on the substrate W forms a liquid film H. The liquid film H of the processing liquid is located on the upper surface W1 of the substrate W. The liquid film H covers the upper surface W1 of the substrate W.

[0134] The liquid film H has an upper surface H1. The upper surface H1 is located higher than the entire pattern P. The entire pattern P is immersed in the liquid film H. The upper surface H1 is located higher than the entire protrusion W2. The entire protrusion W2 is immersed in the liquid film H.

[0135] The recess A is filled with the liquid film H. The entire recess A is filled with only the liquid film H.

[0136] Furthermore, the replacement liquid has already been removed from the upper surface W1 of the substrate W by the processing liquid. Therefore, the replacement liquid is no longer present on the upper surface W1 of the substrate W. No replacement liquid remains in the recess A.

[0137] Gas J is located above the liquid film H. Gas J is in contact with the upper surface H1. The upper surface H1 corresponds to the gas-liquid interface between the liquid film H and gas J.

[0138] The processing liquid supply step may further adjust the thickness of the liquid film H. The thickness of the liquid film H corresponds to the height position of the upper surface H1 of the liquid film H. For example, the thickness of the liquid film H may be adjusted while the nozzle 16a is supplying the processing liquid to the substrate W. For example, the thickness of the liquid film H may be adjusted after the nozzle 16a has stopped supplying the processing liquid. For example, the thickness of the liquid film H may be adjusted by adjusting the rotation speed of the substrate W. For example, the thickness of the liquid film H may be adjusted by adjusting the rotation time of the substrate W.

[0139] Step S16: Solidification film formation process The solidification film formation process involves evaporating the solvent from the processing liquid on the substrate W. The solidification film formation process also involves evaporating the solvent from the liquid film H. The solvent changes into a gas.

[0140] Here, the solvent has a relatively high vapor pressure. Therefore, the solvent evaporates easily.

[0141] Figure 6 is a schematic diagram showing the substrate W during the solidification film formation process. As the solvent evaporates from the liquid film H, the liquid film H is transformed into a solidified film K.

[0142] Specifically, due to the evaporation of the solvent, the solvent leaves the liquid film H, and the amount of solvent contained in the liquid film H decreases. The concentration of the sublimable substance in the liquid film H increases, and the sublimable substance precipitates on the substrate W. That is, the sublimable substance changes from a solute in the processing liquid that forms the liquid film H to a solid. As a result, a solidified film K is formed on the substrate W. The solidified film K is formed on the upper surface W1 of the substrate W. The solidified film K contains the sublimable substance. The solidified film K contains a solid phase of the sublimable substance. The solidified film K does not contain the solvent. The solidified film K is a solid.

[0143] The liquid film H gradually decreases. The solidified film K gradually increases. First, the upper part of the liquid film H is replaced by the solidified film K. The remaining liquid film H is located below the solidified film K. The height of the upper surface H1 of the liquid film H gradually decreases. The solidified film K covers the upper surface H1 of the liquid film H.

[0144] After the solidified film K covers the upper surface H1 of the liquid film H, the liquid film H does not come into contact with the gas J. The liquid-gas interface between the liquid film H and the gas J disappears when the liquid film H is covered by the solidified film K. The liquid film H comes into contact with the solidified film K. The gas J comes into contact with the solidified film K. Therefore, during the solidification process, the liquid film H decreases without exerting any significant force on the protrusions W2. The solvent leaves the substrate W without exerting any significant force on the protrusions W2.

[0145] Figure 7 is a schematic diagram of the substrate W during the solidification film formation process. Ultimately, the entire liquid film H disappears from the substrate W. The liquid is not present on the upper surface W1 of the substrate W. At the end of the solidification film formation process, no liquid film H remains in the recess A. At the end of the solidification film formation process, there is no liquid in the recess A. The recess A is filled with the solidification film K. The entire recess A is filled with only the solidification film K. Pattern P is in contact with the solidification film K. Pattern P is not in contact with the liquid. The protrusion W2 is in contact with the solidification film K. The protrusion W2 is not in contact with the liquid.

[0146] Step S17: Sublimation process The sublimation process sublimes the solidified film. During the sublimation process, the supply unit 15e supplies the first gas to the substrate W. Specifically, the valve 18e opens. The nozzle 16e discharges the first gas. The nozzle 16e blows the first gas towards the upper surface W1 of the substrate W. The first gas is supplied to the solidified film K. As a result, the solidified film K sublimes. The solidified film K changes into a gas without passing through a liquid state. Due to the sublimation of the solidified film K, the solidified film K is removed from the substrate W. Then, the supply unit 15e stops supplying the first gas to the solidified film K. Specifically, the valve 18e closes. The nozzle 16e stops blowing out the first gas.

[0147] Figure 8 is a schematic diagram showing the substrate W during the sublimation process. As the solidified film K sublimes, the solidified film K gradually decreases. As the solidified film K sublimes, gas J enters the recess A.

[0148] When the solidified film K sublimes, it does not change into a liquid. Therefore, during the sublimation process, no liquid is present on the upper surface W1 of the substrate W. No liquid is present in the recess A. The pattern P does not come into contact with the liquid. The protrusions W2 do not come into contact with the liquid. The solidified film K leaves the upper surface W1 of the substrate W without applying any significant force to the protrusions W2.

[0149] Figure 9 is a schematic diagram of the substrate W during the sublimation process. Ultimately, the solidified film K disappears from the upper surface W1 of the substrate W. The recess A is filled with gas J. The entire recess A is filled with gas J only. No liquid is present on the upper surface W1 of the substrate W. The substrate W is completely dried.

[0150] The processing liquid supply process, solidification film formation process, and sublimation process described above correspond to examples of processing liquid usage. The processing liquid is used under normal temperature conditions. The processing liquid is used under normal pressure conditions.

[0151] Step S18: Rotation stop process The rotary drive unit 14 stops the rotation of the substrate holder 13. The substrate W held by the substrate holder 13 stops rotating. The substrate W becomes stationary. The processing unit 11 finishes processing the substrate W.

[0152] <1-6. Technical significance of compound ad> Experimental Examples 1-4 illustrate the technical significance of compound ad as a sublimable substance.

[0153] Experimental Example 1 is performed under the following conditions. Experimental Example 1 involves performing a series of processes on the substrate W, including a chemical solution supply step, a rinse solution supply step, a displacement solution supply step, a processing solution supply step, a solidification film formation step, and a sublimation step.

[0154] The chemical supply process uses hydrofluoric acid as the chemical solution. Hydrofluoric acid is a mixture of hydrogen fluoride and water. The volume ratio of hydrogen fluoride to water is as follows: Hydrogen fluoride:Water = 1:10 (volume ratio)

[0155] The rinsing solution supply process uses deionized water (DIW) as the rinsing solution.

[0156] The displacement solution supply process uses isopropyl alcohol as the displacement solution.

[0157] The processing solution supply process uses a processing solution consisting of a sublimable substance and a solvent. The sublimable substance is pinacolin oxime. The solvent is isopropyl alcohol (IPA). The volume ratio RV of the sublimable substance to the solvent is 2.5 [Vol%].

[0158] In the solidification film formation process, the substrate W is rotated at a rotational speed of 1500 rpm.

[0159] In the sublimation process, the substrate W is rotated at a rotational speed of 1500 rpm while the first gas is supplied to the substrate W.

[0160] In Experimental Example 2, the sublimable substance is acetophenone oxime. All other conditions in Experimental Example 2 are the same as in Experimental Example 1.

[0161] In Experimental Example 3, the sublimable substance is cyclopentanone oxime. All other conditions in Experimental Example 3 are the same as in Experimental Example 1.

[0162] In Experimental Example 4, the sublimable substance is 4-tert-butylphenol. All other conditions in Experimental Example 4 are the same as in Experimental Example 1.

[0163] Each substrate W processed in Experimental Example 1-4 is evaluated according to the following evaluation criteria. The observer observes one or more measurement points on the substrate W. The measurement points are minute regions of the substrate W. The measurement points are magnified 50,000 times, for example, by a scanning electron microscope. The observer determines each protrusion W2 at the measurement point. Specifically, the observer determines whether or not each protrusion W2 has collapsed. The observer counts the number N of determined protrusions W2. The observer counts the number n of collapsed protrusions W2. Here, n is less than or equal to N. The observer calculates the collapse rate. The collapse rate is determined by N and n, as shown in the following equation. Collapse rate = n / N * 100 [%]

[0164] Figure 10 is a table showing the evaluation of each substrate W treated according to Experimental Examples 1-4. Specifically, Figure 10 shows the relationship between Experimental Examples 1-4 and the collapse rate.

[0165] In Experimental Example 1, the collapse rate was 31.2%. In Experimental Example 2, the collapse rate was 23.2%. In Experimental Example 3, the collapse rate was 31.1%. In Experimental Example 4, the collapse rate was 7.2%.

[0166] In each of the experimental examples 1-4, it can be said that the collapse of pattern P was effectively suppressed. In each of the experimental examples 1-4, it can be said that the collapse of the protrusion W2 was effectively suppressed. Therefore, in each of the experimental examples 1-4, it can be said that the substrate W was properly processed while protecting the pattern P formed on the substrate W. In other words, in each of the experimental examples 1-4, it can be said that the substrate W was properly processed.

[0167] Based on Experimental Example 1, the inventors have found the following: Fa1) Pinacoline oxime has the property of being sublimable while protecting the substrate pattern P. Fa2) Based on the attributes described in Fa1) above, pinacolin oxime is suitable for use in substrate processing methods and processing solutions.

[0168] Based on Experimental Example 2, the inventors found the following: Fb1) The acetophenone oxime has the property of being sublimable while protecting the substrate pattern P. Fb2) Based on the attributes described in Fb1) above, acetophenone oxime is suitable for use in substrate processing methods and processing solutions.

[0169] Based on Experimental Example 3, the inventors found the following: Fc1) Cyclopentanone oxime has the property of being sublimable while protecting the substrate pattern P. Fc2) Based on the attributes described in Fc1) above, cyclopentanone oxime is suitable for use in substrate processing methods and processing solutions.

[0170] Based on Experimental Example 4, the inventors have found the following: Fd1)4-tertbutylphenol has the property of being sublimable while protecting the substrate pattern P. Fd2) Based on the attributes described in Fd1) above, 4-tert-butylphenol is suitable for use in substrate processing methods and processing solutions.

[0171] <1-7. Effects of the First Embodiment> The processing solution of the first embodiment is used for processing a substrate W on which a pattern P is formed. Specifically, the processing solution is a processing solution for substrate processing. Specifically, the processing solution is a processing solution for drying substrates. The processing solution contains a sublimable substance and a solvent. The sublimable substance contains at least one of the compounds a, b, c, and d described above. Therefore, the substrate W can be appropriately processed using the processing solution. Specifically, by using the processing solution, the substrate W can be appropriately processed while protecting the pattern P formed on the substrate W. By using the processing solution, the substrate W can be appropriately processed while suppressing the collapse of the protrusions W2 formed on the substrate W.

[0172] The sublimable substance is, for example, pinacolin oxime. Therefore, the substrate treatment method can properly treat the substrate W.

[0173] The sublimable substance is, for example, acetophenone oxime. Therefore, the substrate treatment method can properly treat the substrate W.

[0174] The sublimable substance is, for example, cyclopentanone oxime. Therefore, the substrate treatment method can properly treat the substrate W.

[0175] The sublimable substance is, for example, 4-tert-butylphenol. Therefore, the substrate treatment method can properly treat the substrate W.

[0176] The solvent contains at least one of compounds e1-e10. Therefore, the substrate treatment method can treat the substrate W more effectively.

[0177] The solvent is, for example, isopropyl alcohol. Therefore, the substrate treatment method can treat the substrate W more effectively.

[0178] The substrate processing method of the first embodiment processes a substrate W on which a pattern P is formed. The substrate processing method comprises a processing liquid supply step, a solidification film formation step, and a sublimation step. The processing liquid supply step supplies a processing liquid to the substrate W. The processing liquid contains a sublimable substance and a solvent. The solidification film formation step evaporates the solvent from the processing liquid on the substrate W. The solidification film formation step forms a solidification film K on the substrate W. The solidification film K contains a sublimable substance. The sublimation step sublimes the solidification film K. As described above, the sublimable substance contains at least one of compounds a, b, c, and d. Therefore, the substrate processing method can appropriately process the substrate W. Specifically, the substrate processing method can appropriately process the substrate W while protecting the pattern P formed on the substrate W. The substrate processing method can appropriately process the substrate W while suppressing the collapse of the protrusions W2 formed on the substrate W.

[0179] As described above, the solvent contains at least one of compounds e1-e10. Therefore, the substrate treatment method can treat the substrate W more effectively.

[0180] <2. Second Embodiment> The second embodiment will be described with reference to the drawings. Note that components identical to those in the first embodiment will be denoted by the same reference numerals, and detailed explanations will be omitted.

[0181] <2-1. Substrate W> First, let's describe the substrate W. Figure 11 is a cross-sectional view of the substrate W. Figure 12 is a plan view of the substrate W. As described in the first embodiment, the substrate W has a thin, flat shape. The substrate W has a substantially circular shape in plan view. The substrate W has an upper surface W1. When the substrate W is held by the substrate holding portion 13, the upper surface W1 faces upward.

[0182] The upper surface W1 includes a pattern-forming region W1a and a non-pattern-forming region W1b. The pattern-forming region W1a is the part of the upper surface W1 on which pattern P is formed. The non-pattern-forming region W1b is the part of the upper surface W1 on which pattern P is not formed.

[0183] Figure 11 shows the imaginary line g. The imaginary line g is the boundary between the pattern-forming region W1a and the non-pattern-forming region W1b.

[0184] The pattern-free region W1b is located at the periphery. In plan view, the pattern-free region W1b has an annular shape. The pattern-free region W1b includes the edge of the substrate W. The pattern-free region W1b includes, for example, the bevel portion of the substrate W. The bevel portion is a chamfered portion. The bevel portion is, for example, inclined. The bevel portion is, for example, curved convexly outward from the substrate W. The outward direction is, for example, perpendicular to the axis of rotation B and away from the axis of rotation B.

[0185] The pattern-forming region W1a is surrounded by the non-pattern-forming region W1b in a plan view. The pattern-forming region W1a is located inside the non-pattern-forming region W1b in a plan view. The pattern-forming region W1a includes the central part of the upper surface W1 in a plan view. The pattern-forming region W1a intersects with the axis of rotation B. For example, the pattern-forming region W1a has a circular shape in a plan view.

[0186] Furthermore, the substrate W has a lower surface W3. When the substrate W is held by the substrate holding portion 13, the lower surface W3 faces downward.

[0187] <2-2. Configuration of Processing Unit 11> The second embodiment is substantially the same as the first embodiment in terms of the overview of the substrate processing apparatus 1 and the configuration of the processing liquid generation unit 20. The configuration of the processing unit 11 of the second embodiment will be described below.

[0188] Figure 13 shows the configuration of the processing unit 11 and the processing liquid generation unit 20 of the second embodiment. Figure 13 shows a simplified configuration of the processing liquid generation unit 20. An example of the configuration of the substrate holding unit 13 will be described. The substrate holding unit 13 comprises one base 13a. The base 13a is connected to the rotary drive unit 14. The base 13a is rotatable around the rotation axis B.

[0189] The base 13a has a flat disc shape. Although not shown in the figure, the base 13a has approximately the same size as the substrate W in a plan view. The base 13a has an opening formed in the center of the base 13a. The base 13a has an annular shape in a plan view.

[0190] The substrate holding section 13 includes a plurality of gripping sections 13b. The gripping sections 13b are attached to the base 13a. The gripping sections 13b are rotatable integrally with the base 13a. The gripping sections 13b hold the substrate W. The gripping sections 13b hold the substrate W in a substantially horizontal position.

[0191] Each gripping portion 13b extends upward from the base 13a. Multiple gripping portions 13b are arranged, for example, on a circumference centered on the axis of rotation B. The gripping portions 13b hold the edges of the substrate W.

[0192] When the substrate holder 13 holds the substrate W, the base 13a is positioned below the substrate W. When the substrate holder 13 holds the substrate W, the base 13a faces the lower surface W3 of the substrate W.

[0193] An example configuration of the rotary drive unit 14 will be described. The rotary drive unit 14 comprises a rotary shaft 14a and a motor 14b. The rotary shaft 14a is connected to the base 13a. The rotary shaft 14a extends along the rotation axis B. The rotary shaft 14a has a hollow portion formed inside the rotary shaft 14a. The motor 14b is connected to the rotary shaft 14a. The motor 14b rotates the rotary shaft 14a around the rotation axis B.

[0194] The processing liquid supplied by the supply unit 15a contains a sublimable substance and a solvent. In the second embodiment, the sublimable substance may contain at least one of the compounds ad described above. In the second embodiment, the sublimable substance may not contain at least one of the compounds ad. In the second embodiment, the sublimable substance may contain compounds other than compounds ad.

[0195] Sublimable substances may have a vapor pressure of 100 Pa or less. More specifically, the vapor pressure of sublimable substances at room temperature may be 100 Pa or less.

[0196] Alternatively, the vapor pressure of a sublimable substance at room temperature may be greater than 100 Pa.

[0197] Furthermore, it is preferable that the vapor pressure of the sublimable substance at room temperature is 0.1 Pa or higher.

[0198] The vapor pressures of compounds a, b, c, and d mentioned above are not listed in the public database PubChem website (http: / / pubchem.ncbi.nlm.nih.gov / ).

[0199] The processing unit 11 includes a supply unit 15f in addition to the supply units 15a-15e. The supply unit 15f supplies a second gas to the substrate W.

[0200] The second gas has the same components as the first gas, for example. The second gas is, for example, a dry gas. The second gas is, for example, air. The second gas is, for example, compressed air. The second gas is, for example, an inert gas. The second gas is, for example, nitrogen gas.

[0201] The supply unit 15f is equipped with a nozzle 16f. The nozzle 16f is installed inside the housing 12. The nozzle 16f discharges the second gas. The nozzle 16f blows out the second gas.

[0202] The nozzle 16f directs the second gas out towards the pattern-free region W1b. The nozzle 16f aims at the pattern-free region W1b. The nozzle 16f blows out the second gas towards the pattern-free region W1b.

[0203] The nozzle 16f does not blow out the second gas in the direction that the second gas is directed towards the pattern formation region W1a. The nozzle 16f does not aim at the pattern formation region W1a. The nozzle 16f does not blow out the second gas toward the pattern formation region W1a.

[0204] On the other hand, the direction in which the nozzle 16e blows out the first gas is directed toward the pattern formation region W1a. The nozzle 16e aims at the pattern formation region W1a. The nozzle 16e blows out the first gas toward the pattern formation region W1a.

[0205] The supply unit 15f includes a pipe 17f and a valve 18f. The pipe 17f is connected to the nozzle 16f. At least a portion of the pipe 17f may be provided outside the housing 12. The valve 18f is provided on the pipe 17f. When the valve 18f is open, the nozzle 16f discharges the second gas. When the valve 18f is closed, the nozzle 16f does not discharge the second gas. The valve 18f may be provided outside the housing 12.

[0206] The processing unit 11 includes a heating unit 41. The heating unit 41 is connected to the supply unit 15f. The heating unit 41 is provided, for example, in the piping 17f. The heating unit 41 heats the second gas. The heating unit 41 adjusts the temperature of the second gas. The heating unit 41 includes, for example, at least one of a heat exchanger and a resistance heater. The heating unit 41 may be provided outside the housing 12.

[0207] The supply unit 15f is connected in communication with the second gas supply source 19f. The second gas supply source 19f is connected, for example, to piping 17f. The second gas supply source 19f supplies the second gas to the supply unit 15f. The second gas supply source 19f supplies the second gas to the nozzle 16f through the heating unit 41. The second gas supply source 19f may or may not be an element of the substrate processing apparatus 1.

[0208] Although not shown in the diagram, the control unit 10 controls the supply unit 15f. The control unit 10 controls the valve 18f. Furthermore, the control unit 15f controls the heating unit 41.

[0209] <2-3. Examples of operation of the processing liquid generation unit 20 and the processing unit 11> Figure 14 is a flowchart showing the procedure for the substrate processing method of the second embodiment. The substrate processing method of the second embodiment includes step S21 in addition to steps S1, S11-S18 described in the first embodiment. The operations of steps S1, S11-S14, and S18 are substantially the same between the first and second embodiments. For this reason, the operation of steps S1, S11-S14, and S18 will be omitted. The operation of steps S15-S17 and S21 will be described.

[0210] Step S15: Processing liquid supply process The processing liquid supply process supplies the processing liquid to the substrate W. The processing liquid supply process supplies the processing liquid to the upper surface W1 of the substrate W.

[0211] Figure 15 is a schematic diagram showing the substrate W in the processing liquid supply process. Figure 15 omits the illustration of the substrate holding part 13, etc. The substrate W is in a nearly horizontal position. The substrate W rotates around the rotation axis B.

[0212] The nozzle 16a is located, for example, above the substrate W. The nozzle 16a discharges the processing liquid, for example, onto the upper surface W1 of the substrate W. The nozzle 16a discharges the processing liquid, for example, onto the pattern formation region W1a. The nozzle 16a discharges the processing liquid, for example, onto the central part of the upper surface W1.

[0213] The liquid film H of the processing solution is formed on the upper surface W1 of the substrate W. The liquid film H of the processing solution is formed on the pattern-forming region W1a and on the non-pattern-forming region W1b. The liquid film H of the processing solution covers the upper surface W1 of the substrate W. The liquid film H of the processing solution covers both the pattern-forming region W1a and the non-pattern-forming region W1b.

[0214] Figure 15 illustrates a liquid film H with non-uniform thickness. In Figure 15, the thickness of the liquid film H on the pattern-free region W1b is greater than the thickness of the liquid film H on the pattern-forming region W1a. The liquid film H rises upward in the pattern-free region W1b. This rise of the liquid film H in the pattern-free region W1b is thought to be caused, for example, by the balance between the centrifugal force acting on the liquid film H and the surface tension of the liquid film H.

[0215] Step S16: Solidification film formation process The solidification film formation process involves evaporating the solvent from the processing liquid on the substrate W. The solidification film formation process involves evaporating the solvent from the liquid film H. The solidification film formation process involves forming a solidified film K on the upper surface W1 of the substrate W.

[0216] Figure 16 is a schematic diagram showing the substrate W during the solidification film formation process. The substrate W is in a nearly horizontal position. The substrate W rotates around the rotation axis B.

[0217] The solidified film K covers the entire upper surface W1 of the substrate W.

[0218] Here, the portion of the solidified film K located on the pattern-forming region W1a is called the "first solidified film Ka". The portion of the solidified film K located on the non-pattern-forming region W1b is called the "second solidified film Kb". The first solidified film Ka covers the pattern-forming region W1a. The second solidified film Kb covers the non-pattern-forming region W1b. The second solidified film Kb is not located on the pattern-forming region W1a.

[0219] Figure 16 illustrates a first solidified film Ka and a second solidified film Kb having different thicknesses. In Figure 16, the thickness of the second solidified film Kb is greater than that of the first solidified film Ka. The second solidified film Kb rises higher than the first solidified film Ka. This rise of the second solidified film Kb is thought to be due to the rise of the liquid film H in the pattern-unformed region W1b. The rise of the second solidified film Kb is also thought to be due to the gradual formation of the second solidified film Kb as the substrate W rotates.

[0220] Step S17: Sublimation process The sublimation process involves blowing a first gas towards the first solidified film Ka. The sublimation process then sublimes the first solidified film Ka.

[0221] Figure 17 is a schematic diagram showing the substrate W during the sublimation process. The substrate W is in a nearly horizontal position. The substrate W rotates around the rotation axis B.

[0222] The nozzle 16e is located above the substrate W. The nozzle 16e is located above the pattern formation region W1a (i.e., the first solidified film Ka). The nozzle 16e discharges the first gas toward the pattern formation region W1a (i.e., the first solidified film Ka). The nozzle 16e discharges the first gas toward, for example, the center of the upper surface W1.

[0223] The first gas strikes the first solidified film Ka. After the first gas strikes the first solidified film Ka, it changes direction and flows outward from the substrate W. The first gas flows along the surface of the first solidified film Ka. The first solidified film Ka is exposed to the flow of the first gas.

[0224] As a result, the first solidified film Ka sublimes. Due to the sublimation of the first solidified film Ka, the first solidified film Ka leaves the substrate W (specifically, the pattern formation region W1a).

[0225] Figure 18 is a schematic diagram showing the substrate W during the sublimation process. As shown in Figure 18, when the sublimation process is completed, the entirety of the first solidified film Ka has sublimated. When the sublimation process is completed, the first solidified film Ka is no longer present on the pattern formation region W1a. The pattern formation region W1a is dried by the sublimation process. When the sublimation process is completed, at least a portion of the second solidified film Kb is still present on the non-pattern formation region W1b.

[0226] The processing conditions for the sublimation process are described below. In the sublimation process, the substrate W rotates at a rotational speed v1. In the sublimation process, the nozzle 16e blows out the first gas at a flow rate Q1. In the sublimation process, the first gas has a temperature T1.

[0227] Here, temperature T1 is, for example, equivalent to room temperature. Alternatively, temperature T1 may be lower than room temperature.

[0228] When the sublimation process begins, the solidified film K (including the first solidified film Ka) is at a temperature similar to room temperature. Therefore, even when the first gas is supplied to the first solidified film Ka, the temperature of the first solidified film Ka does not rise. In other words, the first solidified film Ka is not heated by the first gas during the sublimation process. During the sublimation process, the solidified film K maintains a temperature equal to or below room temperature while the first solidified film Ka sublimes. Therefore, during the sublimation process, the first solidified film Ka sublimes without melting.

[0229] Step S21: Removal process The removal process begins after the sublimation process is completed. The period during which the removal process is performed does not overlap with the period during which the sublimation process is performed. For example, the timing of the end of the sublimation process and the start of the removal process are simultaneous.

[0230] When the removal process begins, the entirety of the first solidified film Ka has already sublimated. When the removal process begins, at least a portion of the second solidified film Kb remains on the pattern-non-formed region W1b.

[0231] The removal process involves blowing a second gas towards the second solidified film Kb. The removal process removes the second solidified film Kb from the substrate W.

[0232] Figure 19 is a schematic diagram showing the substrate W during the removal process. The substrate W is in a nearly horizontal position. The substrate W rotates around the rotation axis B.

[0233] The nozzle 16f is located above the substrate W. The nozzle 16f is located above, for example, the pattern-free region W1b (i.e., the second solidified film Kb). The direction in which the nozzle 16f blows out the second gas is directed toward the pattern-free region W1b (i.e., the second solidified film Kb). The nozzle 16f aims at the pattern-free region W1b (i.e., the second solidified film Kb). The nozzle 16f discharges the second gas toward the pattern-free region W1b (i.e., the second solidified film Kb).

[0234] The second gas strikes the second solidification film Kb. The second gas flows across the surface of the second solidification film Kb. The second solidification film Kb is exposed to the flow of the second gas.

[0235] As a result, the second solidification film Kb changes to a gas phase (gas). In other words, the second solidification film Kb vaporizes. By changing to a gas phase, the second solidification film Kb leaves the substrate W (specifically, the pattern-free region W1b).

[0236] Here, the second solidification film Kb may change to the gas phase without passing through the liquid phase. That is, the second solidification film Kb may sublimate. Alternatively, the second solidification film Kb may change to the gas phase via the liquid phase. That is, the second solidification film Kb may melt and then evaporate. In either case, the second solidification film Kb changes to the gas phase and therefore leaves the pattern-non-forming region W1b. Even if the second solidification film Kb temporarily changes to a liquid before changing to a gas, that liquid does not extend to the pattern-forming region W1a. For this reason, from the viewpoint of protecting pattern P, the temporary melting of the second solidification film Kb is acceptable.

[0237] Figure 20 is a schematic diagram showing the substrate W during the removal process. As shown in Figure 20, when the removal process is completed, the entirety of the second solidified film Kb vaporizes. When the removal process is completed, the second solidified film Kb does not remain on the pattern-free region W1b. The pattern-free region W1b is dried by the removal process. As a result, the entire substrate W is dried.

[0238] The processing conditions for the removal process are described below. During the removal process, the substrate W rotates at a rotational speed v2. During the removal process, the nozzle 16f blows out the first gas at a flow rate Q2. During the removal process, the heating unit 41 heats the second gas to a temperature T2. Therefore, during the removal process, the second gas has a temperature of T2.

[0239] Here, the rotational speed v2 may be approximately equal to the rotational speed v1, for example. Alternatively, the rotational speed v2 may be greater than the rotational speed v1. When the rotational speed v2 is greater than the rotational speed v1, the second solidified film Kb is removed even more quickly.

[0240] The flow rate Q2 may be approximately equal to the flow rate Q1, for example. Alternatively, the flow rate Q2 may be greater than the flow rate Q1. When the flow rate Q2 is greater than the flow rate Q1, the second solidification film Kb is removed even more quickly.

[0241] Four examples of temperature T2 are shown below.

[0242] First example of temperature T2 Temperature T2 is approximately equal to temperature T1.

[0243] In the case of the first example, the second cured film Kb is removed as follows. When the removal process starts, the second cured film Kb has a temperature similar to the temperature T1. Therefore, in the first example, the temperature T2 is approximately equal to the temperature of the second cured film Kb when the removal process starts. Thus, even when the second gas is supplied to the second cured film Kb, the temperature of the second cured film Kb does not rise. That is, the second cured film Kb is not heated by the second gas. In the removal process, while the second cured film Kb maintains a temperature equal to or lower than room temperature, the second cured film Kb vaporizes. For this reason, in the removal process, the second cured film Kb is removed without melting. Therefore, in the removal process, the pattern P is reliably protected.

[0244] Second example of the temperature T2 The temperature T2 is higher than the temperature T1.

[0245] In the case of the second example, the second cured film Kb is removed as follows. In the second example, the temperature T2 is higher than the temperature of the second cured film Kb when the removal process starts. Thus, when the second gas is supplied to the second cured film Kb, the temperature of the second cured film Kb rises. That is, the second cured film Kb is heated by the second gas. In the removal process, while the second cured film Kb is heated, the second cured film Kb changes to the gas phase. Therefore, the second cured film Kb is quickly removed.

[0246] Third example of the temperature T2 The temperature T2 is higher than room temperature.

[0247] In the case of the third example, the second cured film Kb is removed as follows. When the removal process starts, the second cured film Kb has a temperature equal to or lower than room temperature. Therefore, in the third example, the temperature T2 is higher than the temperature of the second cured film Kb when the removal process starts. Thus, the second cured film Kb is heated by the second gas. In the removal process, while the second cured film Kb is heated, the second cured film Kb changes to the gas phase. Therefore, the second cured film Kb is quickly removed.

[0248] Fourth example of the temperature T2 For example, the temperature T2 is higher than the melting point MP of the sublimable substance at normal pressure. For example, when the sublimable substance contains a plurality of compounds, the temperature T2 is higher than any of the melting points MP of the compounds contained in the sublimable substance. For example, the temperature T2 is higher than the melting point of the solidified film K at normal pressure.

[0249] The melting point MP of the above-described compound a is referred to as melting point MPa. Similarly, the melting points MP of compounds b, c, and d are referred to as melting points MPb, MPc, and MPd, respectively. For example, when the sublimable substance is compound a, the temperature T2 is higher than the melting point MPa. For example, when the sublimable substance contains compounds a, b, c, and d, the temperature T2 is higher than any of the melting points MPa, MPb, MPc, and MPd.

[0250] For reference, the values of the melting points MPa, MPb, MPc, and MPd are shown. · Melting point MPa of compound a at standard atmospheric pressure: 76 degrees · Melting point MPb of compound b at standard atmospheric pressure: 60 degrees · Melting point MPc of compound c at standard atmospheric pressure: 58 degrees · Melting point MPd of compound d at standard atmospheric pressure: 101.1 degrees Here, the standard atmospheric pressure is 101325 Pa.

[0251] In the case of the fourth example, the second solidified film Kb is removed as follows. When the removal process starts, the second solidified film Kb has a temperature lower than the melting point MP. Therefore, in the fourth example, the temperature T2 is higher than the temperature of the second solidified film Kb when the removal process starts. Thus, the second solidified film Kb is heated by the second gas. In the removal process, while the second solidified film Kb is heated, the second solidified film Kb changes to the gas phase. Therefore, the second solidified film Kb is quickly removed.

[0252] As described above, in the second, third, and fourth examples of the temperature T2, the second solidified film Kb is heated by the second gas. In the second, third, and fourth examples of the temperature T2, the second gas is an example of the second gas of the present invention and also an example of the high-temperature fluid of the present invention.

[0253] <2-4. Effects of the Second Embodiment> The substrate processing method of the second embodiment processes a substrate W. The substrate W has an upper surface W1. The upper surface W1 includes a pattern-forming region W1a and a non-pattern-forming region W1b. A pattern P is formed in the pattern-forming region W1a. No pattern P is formed in the non-pattern-forming region W1b.

[0254] The substrate processing method processes the substrate W described above. The substrate processing method comprises a processing liquid supply step and a solidification film formation step. The processing liquid supply step supplies the processing liquid to the substrate W. The processing liquid contains a sublimable substance and a solvent. The processing liquid supply step forms a liquid film H of the processing liquid on the upper surface W1 of the substrate W. The solidification film formation step evaporates the solvent from the liquid film H. The solidification film formation step forms a solidification film K on the upper surface W1 of the substrate W. The solidification film K contains a sublimable substance. The solidification film K has a first solidification film Ka and a second solidification film Kb. The first solidification film Ka is located on the pattern formation region W1a. The second solidification film Kb is located on the pattern non-formation region W1b.

[0255] The substrate processing method includes a sublimation step. The sublimation step involves blowing a first gas toward the first solidified film Ka. The sublimation step sublimes the first solidified film Ka. As the first solidified film Ka sublimes, it leaves the pattern formation region W1a. In this way, the sublimation step dries the pattern formation region W1a while protecting the pattern P. The sublimation step dries the pattern formation region W1a while suppressing the collapse of the pattern P (protrusions W2).

[0256] The substrate processing method includes a removal step. The removal step removes the second solidified film Kb from the substrate W. As a result, the removal step dries the pattern-free region W1b.

[0257] Here, the second solidified film Kb is located on the pattern-non-formed region W1b. That is, the second solidified film Kb is not located on the pattern-formed region W1a. Therefore, even if the removal of the second solidified film Kb is accelerated, there is no risk of the pattern P collapsing. Thus, the removal process can efficiently remove the second solidified film Kb from the substrate W.

[0258] In summary, the substrate processing method includes a sublimation step and a removal step. The sublimation step sublimes the first solidification film Ka. The removal step removes the second solidification film Kb. Thus, the sublimation step does not require the sublimation of the second solidification film Kb. The removal step can efficiently remove the second solidification film Kb from the substrate W. Therefore, the substrate W is efficiently dried by both the sublimation step and the removal step. Consequently, the substrate processing method can efficiently process the substrate W.

[0259] In particular, even when the second solidification film Kb is less likely to sublimate than the first solidification film Ka, the removal process can efficiently remove the second solidification film Kb. For example, as shown in Figure 16, even when the second solidification film Kb has a thickness greater than the thickness of the first solidification film Ka, the removal process can efficiently remove the second solidification film Kb.

[0260] The substrate processing method of the second embodiment includes a removal step, whereas the conventional substrate processing method does not. In the conventional substrate processing method, the sublimation step sublimes the entire solidification film K. Therefore, in the conventional substrate processing method, it may not be possible to efficiently sublimate the solidification film K. In particular, when the second solidification film Kb is more difficult to sublimate than the first solidification film Ka, the entire solidification film K will not be easily sublimated by the sublimation step in the conventional substrate processing method. For example, as shown in Figure 16, when the second solidification film Kb has a greater thickness than the first solidification film Ka, the second solidification film Kb will not be easily sublimated by the sublimation step in the conventional substrate processing method. In these cases, the sublimation step requires a significantly longer time. As a result, the throughput of the substrate processing method decreases. Thus, when the second solidification film Kb is more difficult to sublimate than the first solidification film Ka, the substrate processing method of the second embodiment exhibits a very significant effect compared to the conventional substrate processing method.

[0261] The removal process begins after the sublimation process is completed. Therefore, the removal process is not performed until the sublimation process is finished. Consequently, the removal process is not performed until the drying of the pattern-forming region W1a is complete. Thus, the pattern P can be protected more effectively.

[0262] The removal process involves converting the second solidified film Kb into a gas phase. By converting the second solidified film Kb into a gas phase, the second solidified film Kb can be suitably removed from the substrate W.

[0263] Here, in the removal process, the second solidification film Kb may temporarily turn into a liquid before it turns into a gas. That is, in the removal process, the second solidification film Kb may melt. As described above, the second solidification film Kb is located on the pattern-non-forming region W1b. The second solidification film Kb is not located on the pattern-forming region W1a. Therefore, even if the second solidification film Kb temporarily turns into a liquid, that liquid will not reach the pattern-forming region W1a. Thus, even if the second solidification film Kb temporarily turns into a liquid, the pattern P can be adequately protected.

[0264] The removal step involves vaporizing the second solidification film Kb. By vaporizing the second solidification film Kb, it can be suitably removed from the substrate W.

[0265] The removal process involves blowing a second gas towards the second solidified film Kb. This allows the second gas to effectively convert the second solidified film Kb into a gaseous phase. Therefore, the removal process effectively removes the second solidified film Kb from the substrate W.

[0266] The removal process does not involve blowing the second gas towards the pattern formation region W1a. Therefore, the pattern P can be effectively protected during the removal process.

[0267] The flow rate Q2 is, for example, greater than the flow rate Q1. Specifically, the flow rate Q2 of the second gas blown toward the second solidified film Kb in the removal process is greater than the flow rate Q1 of the first gas blown toward the first solidified film Ka in the sublimation process. Therefore, the second gas can efficiently convert the second solidified film Kb into a gas phase. Thus, the removal process can efficiently remove the second solidified film Kb from the substrate W. In other words, the removal of the second solidified film Kb can be suitably promoted. For example, the time required for the removal process can be shortened.

[0268] In the removal step, the second solid film Kb is heated by the second gas. The second gas can more efficiently convert the second solid film Kb into the gas phase. Therefore, in the removal step, the second solid film Kb can be removed from the substrate W more efficiently. In other words, the removal of the second solid film Kb can be suitably promoted.

[0269] The second gas has, for example, a temperature T2 higher than the temperature T1 of the first gas. For this reason, the second gas can suitably heat the second solid film Kb. Therefore, the removal of the second solid film Kb can be suitably promoted.

[0270] The second gas has, for example, a temperature T2 higher than room temperature. For this reason, the second gas can suitably heat the second solid film Kb. Therefore, the removal of the second solid film Kb can be suitably promoted.

[0271] The second gas has, for example, a temperature T2 higher than the melting point MP of the sublimable substance. The second gas can more efficiently convert the second solid film Kb into the gas phase. Even if the second solid film Kb temporarily changes into a liquid, the pattern P can be suitably protected.

[0272] The second gas has, for example, a temperature higher than the melting point of the second solid film Kb. The second gas can more efficiently convert the second solid film Kb into the gas phase. Even if the second solid film Kb temporarily changes into a liquid, the pattern P can be suitably protected.

[0273] The rotational speed v2 of the substrate W in the removal step is, for example, larger than the rotational speed v1 of the substrate W in the sublimation step. For this reason, the second solid film Kb can be removed from the substrate W more efficiently.

[0274] In the sublimation step, the solid film K is not heated. For this reason, in the sublimation step, the solid film K can be sublimated appropriately. In other words, the sublimation step can suitably suppress the solid film K from changing into a liquid. The sublimation step can suitably suppress the solid film K from melting. Therefore, the pattern P can be protected more suitably.

[0275] The sublimation process does not heat the substrate W. Therefore, the sublimation process can properly sublimate the solidified film K. Consequently, the pattern P can be protected more effectively.

[0276] Sublimable materials, for example, have a vapor pressure of 100 Pa or less at room temperature. When the vapor pressure of a sublimable material is 100 Pa or less, its vapor pressure is relatively low. The inventors have found that when the vapor pressure of a sublimable material is relatively low, the second solidification film Kb is less likely to sublimate than the first solidification film Ka. Furthermore, the inventors have found that when the vapor pressure of a sublimable material is relatively low, the thickness of the second solidification film Kb tends to be greater than the thickness of the first solidification film Ka. As described above, the substrate processing method of the second embodiment includes a removal step in addition to the sublimation step. Therefore, even when the second solidification film Kb is less likely to sublimate, the substrate processing method of the second embodiment can suitably remove the second solidification film Kb from the substrate W. Consequently, even when the vapor pressure of the sublimable material is 100 Pa or less, the substrate processing method can efficiently process the substrate W. In other words, when the vapor pressure of the sublimable material is 100 Pa or less, the substrate processing method is extremely effective.

[0277] <3. Third Embodiment> The substrate processing apparatus 1 of the third embodiment will be described with reference to the drawings. Note that components identical to those of the first or second embodiment are denoted by the same reference numerals, and detailed explanations are omitted.

[0278] The third embodiment is substantially the same as the first embodiment in terms of the overview of the substrate processing apparatus 1 and the configuration of the processing liquid generation unit 20. The configuration of the processing unit 11 of the third embodiment will be described below.

[0279] <3-1. Configuration of Processing Unit 11> Figure 21 shows the configuration of the processing unit 11 and the processing liquid generation unit 20 of the third embodiment. Figure 21 shows a simplified configuration of the processing liquid generation unit 20. The processing unit 11 includes a heating unit 42. The heating unit 42 heats the second solidification film Kb. The heating unit 42 adjusts the temperature of the second solidification film Kb.

[0280] Specifically, the heating unit 42 heats the substrate W. By heating the substrate W, the heating unit 42 heats the second solidification film Kb that is in contact with the substrate W. The heating unit 42 adjusts the temperature of the substrate W. By adjusting the temperature of the substrate W, the heating unit 42 adjusts the temperature of the second solidification film Kb.

[0281] An example of the configuration of the heating section 42 will be described. The heating section 42 includes a resistance heater 43. The resistance heater 43 is positioned below the substrate W. The resistance heater 43 includes a heating element. The resistance heater 43 is also called an electric heater. The resistance heater 43 heats the substrate W. The resistance heater 43 heats the lower surface W3 of the substrate W. The resistance heater 43 heats the entire substrate W. The resistance heater 43 heats both the pattern formation region W1a and the non-pattern formation region W1b.

[0282] The heating section 42 includes a plate 44. A resistance heater 43 is installed on the plate 44. The resistance heater 43 is installed, for example, on the surface or inside the plate 44. The plate 44 is positioned below the substrate W supported by the substrate holding section 13. The plate 44 is positioned above the base 13a, for example.

[0283] The plate 44 has a flat, disc-like shape. Although not shown in the figure, the plate 44 is approximately the same size as the substrate W in a plan view. The plate 44 has a circular shape in a plan view.

[0284] The heating unit 42 includes a fixed shaft portion 45. The fixed shaft portion 45 supports the plate 44. The fixed shaft portion 45 extends along the rotation axis B. The fixed shaft portion 45 is positioned in the hollow portion of the rotation shaft portion 14a. Even when the rotation shaft portion 14a rotates, the fixed shaft portion 45 does not rotate. Therefore, even when the rotation drive unit 14 rotates the substrate holding portion 13, the resistance heater 43 and the plate 44 do not rotate.

[0285] The heating unit 42 is equipped with a power supply 46. The power supply 46 is electrically connected to the resistance heater 43. The power supply 46 supplies power to the resistance heater 43. The resistance heater 43 generates heat due to the power supplied from the power supply 46.

[0286] The power supply 46 further adjusts the amount of heat generated by the resistor heater 43. By adjusting the amount of heat generated by the resistor heater 43, the power supply 46 adjusts the temperature of the substrate W.

[0287] The processing liquid supplied by the supply unit 15a is the same as in the second embodiment. Specifically, the processing liquid contains a sublimable substance and a solvent. In the third embodiment, the sublimable substance may contain at least one of the compounds ad described above. In the third embodiment, the sublimable substance may not contain at least one of the compounds ad. In the third embodiment, the sublimable substance may contain compounds other than compounds ad.

[0288] Sublimable substances may have a vapor pressure of 100 Pa or less. More specifically, the vapor pressure of sublimable substances at room temperature may be 100 Pa or less.

[0289] Alternatively, the vapor pressure of a sublimable substance at room temperature may be greater than 100 Pa.

[0290] Furthermore, it is preferable that the vapor pressure of the sublimable substance at room temperature is 0.1 Pa or higher.

[0291] Although not shown in the diagram, the control unit 10 controls the heating unit 42. The control unit 10 also controls the power supply 46.

[0292] <3-2. Examples of operation of the processing liquid generation unit 20 and the processing unit 11> For convenience, please refer to Figure 14. The substrate processing method of the third embodiment includes step S21 in addition to steps S1 and S11-S18 described in the first embodiment. The operations of steps S1, S11-S14, and S18 are substantially the same between the first and third embodiments. For this reason, the operation of steps S1, S11-S14, and S18 will be omitted. The operations of steps S15-S17 are substantially the same between the second and third embodiments. For this reason, the operation of steps S15-S17 will be briefly described, and the operation of step S21 will be described in detail.

[0293] Step S15: Processing liquid supply process For convenience, refer to Figure 15. The supply unit 15a supplies the processing liquid to the substrate W. The supply unit 15a supplies the processing liquid to the upper surface W1 of the substrate W. A liquid film H of the processing liquid is formed on the upper surface W1 of the substrate W.

[0294] Step S16: Solidification film formation process For convenience, refer to Figure 16. The solidification film formation step involves evaporating the solvent from the processing liquid on the substrate W. The solidification film formation step involves evaporating the solvent from the liquid film H. The solidification film formation step involves forming a solidified film K on the upper surface W1 of the substrate W.

[0295] The solidified film K has a first solidified film Ka and a second solidified film Kb. The first solidified film Ka is located on the pattern-forming region W1a. The second solidified film Kb is located on the non-pattern-forming region W1b. The second solidified film Kb is not located on the pattern-forming region W1a. The first solidified film Ka is in contact with the pattern-forming region W1a. The second solidified film Kb is in contact with the non-pattern-forming region W1b.

[0296] Step S17: Sublimation process For convenience, refer to Figures 17 and 18. The supply unit 15e blows the first gas toward the first solidification film Ka. As a result, the first solidification film Ka sublimes.

[0297] In the sublimation process, the substrate W rotates at a rotational speed v1. In the sublimation process, the nozzle 16e blows out the first gas at a flow rate Q1. In the sublimation process, the first gas has a temperature T1. Temperature T1 is, for example, equivalent to or lower than room temperature. In the sublimation process, the first solidified film Ka sublimes while the solidified film K maintains a temperature equivalent to or lower than room temperature.

[0298] Step S21: Removal process The removal process begins after the sublimation process is complete. The removal process involves heating the second solidified film Kb. This removes the second solidified film Kb from the substrate W.

[0299] Figure 22 is a schematic diagram showing the substrate W during the removal process. The substrate W is in a nearly horizontal position. The substrate W rotates around the rotation axis B.

[0300] The resistive heater 43 heats the lower surface W3 of the substrate W. The resistive heater 43 heats the entire lower surface W3 of the substrate W. The resistive heater 43 heats the pattern formation region W1a and the non-pattern formation region W1b.

[0301] The second solidified film Kb is heated via the substrate W. Specifically, the second solidified film Kb is heated via the pattern-free region W1b that is in contact with the second solidified film Kb.

[0302] When the second solidification film Kb is heated, it vaporizes. As a result of vaporization, the second solidification film Kb leaves the substrate W (specifically, the pattern-free region W1b).

[0303] Here, the second solidification film Kb may change to the gas phase without passing through the liquid phase. Alternatively, the second solidification film Kb may change to the gas phase via the liquid phase. In either case, the second solidification film Kb changes to the gas phase and therefore leaves the pattern-non-forming region W1b. Even if the second solidification film Kb temporarily changes to a liquid before changing to a gas, that liquid does not extend into the pattern-forming region W1a.

[0304] Figure 23 is a schematic diagram showing the substrate W during the removal process. As shown in Figure 23, when the removal process is completed, the entirety of the second solidified film Kb vaporizes. When the removal process is completed, the second solidified film Kb does not remain on the pattern-free region W1b. The pattern-free region W1b is dried by the removal process. As a result, the entire substrate W is dried.

[0305] The processing conditions for the removal process are described below. During the removal process, the substrate W rotates at a rotational speed v2. During the removal process, the heating unit 42 heats the substrate W to a temperature Th. Therefore, during the removal process, the substrate W has a temperature Th.

[0306] Here, the rotational speed v2 may be approximately equal to the rotational speed v1, for example. Alternatively, the rotational speed v2 may be greater than the rotational speed v1. When the rotational speed v2 is greater than the rotational speed v1, the second solidified film Kb is removed even more quickly.

[0307] Three examples of temperature Th are shown below.

[0308] First example of temperature Th Temperature Th is higher than temperature T1.

[0309] In the first example, the second solidified film Kb is removed as follows. When the removal process begins, the second solidified film Kb has a temperature approximately the same as temperature T1. Therefore, in the first example, temperature Th is higher than the temperature of the second solidified film Kb at the start of the removal process. Thus, when the substrate W is heated to temperature Th, the temperature of the second solidified film Kb rises. That is, the second solidified film Kb is heated through the substrate W (specifically, the pattern-free region W1b). During the removal process, the second solidified film Kb is heated and changes to the gas phase. Therefore, the second solidified film Kb is removed quickly.

[0310] Second example of temperature Th Temperature Th is higher than room temperature.

[0311] In the second example, the second solidified film Kb is removed as follows. When the removal process begins, the second solidified film Kb has a temperature equal to or below room temperature. Therefore, in the second example, the temperature Th is higher than the temperature of the second solidified film Kb when the removal process begins. Thus, the second solidified film Kb is heated through the substrate W (specifically, the pattern-free region W1b). During the removal process, the second solidified film Kb is heated and changes to the gas phase. Therefore, the second solidified film Kb is removed quickly.

[0312] Third example of temperature Th For example, temperature Th is higher than the melting point MP of the sublimable substance at atmospheric pressure. For example, temperature Th is higher than the melting point K of the solidified film at atmospheric pressure.

[0313] In the third example, the second solidified film Kb is removed as follows. When the removal process begins, the second solidified film Kb has a temperature lower than its melting point MP. Therefore, in the third example, the temperature Th is higher than the temperature of the second solidified film Kb at the start of the removal process. Thus, the second solidified film Kb is heated through the substrate W (specifically, the pattern-free region W1b). During the removal process, the second solidified film Kb is heated and changes to the gas phase. Therefore, the second solidified film Kb is removed quickly.

[0314] As described above, in the first, second, and third examples at temperature Th, the second solidified film Kb is heated via the substrate W.

[0315] <3-3. Effects of the Third Embodiment> The third embodiment also provides the same effects as the second embodiment. For example, the substrate processing method of the third embodiment also includes a removal step in addition to the sublimation step, so the substrate W can be processed efficiently. Furthermore, the third embodiment provides the following effects.

[0316] The removal process involves heating the second solidified film Kb. Therefore, the removal process can remove the second solidified film Kb from the substrate W more efficiently.

[0317] The removal process involves heating the pattern-free region W1b and heating the second solidified film Kb through the pattern-free region W1b. The second solidified film Kb is located on the pattern-free region W1b. Therefore, the pattern-free region W1b is in contact with the second solidified film Kb. Thus, by heating the pattern-free region W1b, the second solidified film Kb can be suitably heated through the pattern-free region W1b.

[0318] The removal step involves heating the non-patterned region W1b to a temperature Th higher than the temperature T1 of the first gas. This allows the second solidified film Kb to be heated effectively, thereby effectively promoting the drying of the non-patterned region W1b.

[0319] The removal process involves heating the pattern-free region W1b to a temperature Th higher than room temperature. This allows for optimal heating of the second solidified film Kb, thereby effectively promoting the drying of the pattern-free region W1b.

[0320] The removal process involves heating the non-pattern-forming region W1b to a temperature Th higher than the melting point MP of the sublimable material. Taking advantage of the fact that the second solidified film Kb is not located on the pattern-forming region W1a, the second solidified film Kb can be heated to a relatively high temperature. Therefore, the second solidified film Kb can be converted to the gas phase more efficiently.

[0321] The removal process, for example, has a pattern-non-forming region W1b at a temperature higher than the melting point of the second solidified film Kb. Taking advantage of the fact that the second solidified film Kb is not located on the pattern-forming region W1a, the second solidified film Kb can be heated to a relatively high temperature. Therefore, the second solidified film Kb can be converted to the gas phase more efficiently.

[0322] The removal process involves heating the lower surface W3 of the substrate W. This allows for optimal heating of the pattern-free region W1b.

[0323] The removal process involves heating the entire substrate W. This allows for optimal heating of the non-patterned region W1b. Furthermore, the removal process removes organic matter adhering to the substrate W along with the second solidified film Kb.

[0324] The removal process involves heating the second solidified film Kb with a resistance heater 43. This allows the second solidified film Kb to be heated appropriately.

[0325] The rotation speed v2 of the substrate W in the removal process is greater than, for example, the rotation speed v1 of the substrate W in the sublimation process. Therefore, the second solidified film Kb can be removed from the substrate W more efficiently.

[0326] The present invention is not limited to the embodiments described below and can be modified and implemented as follows.

[0327] (1) In the first to third embodiments, the processing liquid was generated in the tank 21. However, it is not limited to this. For example, the processing liquid may be generated in a flow path communicating with the supply unit 15a.

[0328] Figure 24 shows the configuration of the processing unit 11 and processing liquid generation unit 20 of a modified embodiment. Note that components identical to those in the first embodiment are denoted by the same reference numerals, and detailed explanations are omitted.

[0329] The processing liquid generation unit 20 comprises a first tank 51 and a second tank 52. The first tank 51 stores a sublimable substance. For example, the first tank 51 may store a solvent together with the sublimable substance. The second tank 52 stores a solvent. For example, the second tank 52 stores only the solvent.

[0330] The processing liquid generation unit 20 includes a mixing unit 54. The mixing unit 54 generates the processing liquid. The mixing unit 54 is connected in communication with the first tank 51 and the second tank 52.

[0331] The mixing unit 54 is further connected to the supply unit 15a. The mixing unit 54 sends the processed liquid to the supply unit 15a.

[0332] The mixing section 54 includes pipes 55a and 55b and a fitting 56. Pipe 55a connects to the first tank 51 via the fitting 56. Pipe 55b connects to the second tank 52 via the fitting 56. The fitting 56 is further connected to pipe 17a. Pipes 17a, 55a, and 55b are all connected to each other via the fitting 56.

[0333] The mixing unit 54 is equipped with pumps 57a and 57b. Pumps 57a and 57b are provided in piping 55a and 55b, respectively. Pump 57a delivers a sublimable substance from the first tank 51 to the fitting 56 through piping 55a. Pump 57b delivers a solvent from the second tank 52 to the fitting 56 through piping 55b.

[0334] The mixing section 54 is equipped with filters 58a and 58b. Filters 58a and 58b are provided in pipes 55a and 55b, respectively. Filter 58a filters the sublimable substance flowing through pipe 55a. Filter 58b filters the solvent flowing through pipe 55b.

[0335] The mixing unit 54 includes valves 59a and 59b. Valves 59a and 59b are provided in pipes 55a and 55b, respectively. Valve 59a adjusts the flow rate of the sublimable substance flowing through pipe 55a. Valve 59b adjusts the flow rate of the solvent flowing through pipe 55b. Valves 59a and 59b may each include, for example, a flow control valve. Valves 59a and 59b may each include, for example, a flow control valve and an on / off valve.

[0336] The sublimable substance flows into the fitting 56 at a flow rate regulated by valve 59a. The solvent flows into the fitting 56 at a flow rate regulated by valve 59b. The sublimable substance and the solvent merge at the fitting 56. A processing liquid containing the sublimable substance and the solvent is generated at the fitting 56. The generated processing liquid flows from the fitting 56 to the supply unit 15a.

[0337] (2) The second and third embodiments may be combined as appropriate. For example, in the removal step of the second embodiment, the substrate W may be heated by the heating unit 42 as described in the third embodiment. For example, in the removal step of the third embodiment, the second gas may be blown toward the second solidified film Kb as described in the second embodiment.

[0338] (3) In the second and third embodiments, the period during which the removal process is performed does not overlap with the period during which the sublimation process is performed. However, this is not limited to the above. For example, the period during which the removal process is performed may overlap with at least a portion of the period during which the sublimation process is performed. According to this modified embodiment, the total time required for the sublimation process and the removal process can be shortened. Therefore, the substrate W can be processed more efficiently.

[0339] For example, the removal process may begin after the sublimation process has started. For example, the removal process may begin after the sublimation process has started but before it has finished. According to this modified embodiment, drying of the pattern formation region W1a begins before the removal process. Therefore, it is possible to suitably achieve both protection of the pattern P and efficient processing of the substrate W.

[0340] (4) In the second embodiment, nozzle 16e blows out a first gas in the sublimation process, and nozzle 16f blows out a second gas in the removal process. Thus, the first gas and the second gas are blown out by two different nozzles 16e and 16f. However, it is not limited to this. The first gas and the second gas may be blown out by a common nozzle. For example, nozzle 16e may blow out the first gas in the sublimation process and blow out the second gas in the removal process. Nozzle 16e may be movably provided between a first processing position above the pattern forming region W1a and a second processing position above the non-pattern forming region W1b. When nozzle 16e is in the first processing position, nozzle 16e may blow out the first gas onto the first solidified film Ka, and when nozzle 16e is in the second processing position, nozzle 16e may blow out the second gas onto the second solidified film Kb. The nozzle 16e may be movably positioned between a first position targeting the pattern-forming region W1a and a second position targeting the non-pattern-forming region W1b. When the nozzle 16e is in the first position, it may blow a first gas onto the first solidified film Ka, and when the nozzle 16e is in the second position, it may blow a second gas onto the second solidified film Kb.

[0341] (5) In the second embodiment, the nozzle 16f that blows out the second gas in the removal step is different from the nozzle 16e that blows out the first gas in the sublimation step. However, it is not limited to this. The first gas and the second gas may be blown out by a common nozzle. For example, the nozzle 16e may blow out the first gas in the sublimation step and the second gas in the removal step. The nozzle 16e may be movably provided between a first processing position above the pattern forming region W1a and a second processing position above the non-pattern forming region W1b. When the nozzle 16e is in the first processing position, the nozzle 16e may blow out the first gas onto the first solidified film Ka, and when the nozzle 16e is in the second processing position, the nozzle 16e may blow out the second gas onto the second solidified film Kb.

[0342] (6) In the second embodiment, the removal step did not blow the second gas toward the pattern forming region W1a. However, it is not limited to this. The removal step may blow the second gas toward at least a part of the pattern forming region W1a.

[0343] (7) In the second and third embodiments, the supply unit 15e did not blow the first gas toward the pattern forming region W1a during the removal process. However, it is not limited to this. For example, during the removal process, the supply unit 15e may blow the first gas toward the pattern forming region W1a.

[0344] (8) In the third embodiment, the second solidified film Kb is heated via the pattern-free region W1b. However, it is not limited to this. For example, the second solidified film Kb may be heated without going through the pattern-free region W1b. For example, the second solidified film Kb may be heated directly. For example, the resistance heater 43 may be placed above the substrate W. For example, the resistance heater 43 may radiate heat toward the second solidified film Kb.

[0345] (9) In the third embodiment, the entire substrate W was heated. However, it is not limited to this. For example, only a part of the substrate W may be heated.

[0346] (10) In the third embodiment, not only the pattern-unformed region W1b but also the pattern-formed region W1a was heated. However, it is not limited to this. For example, the pattern-formed region W1a does not need to be heated. For example, the resistance heater 43 does not need to be placed below the pattern-formed region W1a. For example, substantially only the pattern-unformed region W1b may be heated. For example, the resistance heater 43 may be placed only below the pattern-unformed region W1b.

[0347] (11) In the third embodiment, the second solidified film Kb was heated by a resistance heater 43. However, it is not limited to this. For example, the second solidified film Kb may be heated by a lamp heater. A lamp heater is also called a light heater. A lamp heater emits light, for example, infrared light. A lamp heater includes a light source, for example, a lamp that emits light. The lamp heater may be placed, for example, above the substrate W. The lamp heater may heat the second solidified film Kb by irradiating it with light, for example. Alternatively, the lamp heater may be placed below the substrate W. The lamp heater may heat the pattern-free region W1b by irradiating the lower surface W3 of the substrate W with light, for example, and heat the second solidified film Kb through the pattern-free region W1b. In this way, the second solidified film Kb can also be suitably heated by a lamp heater.

[0348] For example, the second solidification film Kb may be heated by a high-temperature fluid. The high-temperature fluid is a gas or liquid having a temperature capable of heating the second solidification film Kb. For example, the high-temperature fluid may be discharged toward the lower surface W3 of the substrate W. For example, the processing unit 11 may be equipped with a nozzle for discharging the high-temperature fluid. The nozzle for discharging the high-temperature fluid may be located, for example, below the substrate W. For example, the nozzle for discharging the high-temperature fluid may be located in the opening of the base 13a or in the hollow part of the rotating shaft portion 14a. The pattern-free region W1b may be heated by the high-temperature fluid, and the second solidification film Kb may be heated through the pattern-free region W1b. In this way, the second solidification film Kb can also be suitably heated by a high-temperature fluid.

[0349] (12) In the second and third embodiments, the sublimation step may sublimate at least a portion of the second solidified film Kb. This reduces the amount of the second solidified film Kb that the removal step removes. Thus, the removal step can easily remove the second solidified film Kb.

[0350] (13) In the processing liquid supply step of the second and third embodiments, as shown in Figure 15, the liquid film H was raised upward in the pattern-non-formed region W1b. However, it is not limited to this. For example, the liquid film H does not have to be substantially raised upward in the pattern-non-formed region W1b. For example, the thickness of the liquid film H on the pattern-non-formed region W1b may be approximately equal to the thickness of the liquid film H on the pattern-formed region W1a. In this case, the raised portion of the second solidified film Kb is relatively small. Therefore, the removal step can easily remove the second solidified film Kb.

[0351] (14) In the solidification film formation step of the second and third embodiments, the second solidification film Kb was raised upward as shown in Figure 16. However, it is not limited to this. For example, the second solidification film Kb does not have to be substantially raised upward. For example, the thickness of the second solidification film Kb may be approximately equal to the thickness of the first solidification film Ka. In this case, the removal step can easily remove the second solidification film Kb.

[0352] (15) In the first to third embodiments, the system includes a chemical solution supply step, a rinse solution supply step, and a replacement solution supply step. However, it is not limited thereto. For example, at least one of the chemical solution supply step, the rinse solution supply step, and the replacement solution supply step may be omitted. For example, all of the chemical solution supply step, the rinse solution supply step, and the replacement solution supply step may be omitted.

[0353] (16) In the first to third embodiments, when the processing liquid supply step was performed, the liquid (e.g., displacement liquid) was present on the substrate W. That is, the processing liquid supply step supplied the processing liquid to the substrate W, which was not dry. However, it is not limited to this. For example, when the processing liquid supply step was performed, the liquid (e.g., displacement liquid) did not have to be present on the substrate W. For example, the processing liquid supply step may supply the processing liquid to the substrate W, which was dry.

[0354] (17) In the first to third embodiments, the processing liquid supply step removed the replacement liquid from the substrate W using the processing liquid. However, it is not limited to this. For example, the processing liquid supply step may wash the substrate W with the processing liquid. For example, the processing liquid supply step may remove foreign matter adhering to the substrate W using the processing liquid. For example, the processing liquid supply step may dissolve foreign matter adhering to the substrate W using the processing liquid. Foreign matter is, for example, resist residue.

[0355] (18) In the first to third embodiments, the solidification film formation step did not supply gas to the substrate W. However, it is not limited to this. The solidification film formation step may supply gas to the substrate W. The solidification film formation step may supply gas to the processing liquid on the substrate W. As a result, the solidification film formation step can efficiently form a solidified film K on the substrate W.

[0356] (19) In the first to third embodiments, the chemical solution was, for example, hydrofluoric acid. Therefore, in the chemical solution supply step, the substrate W is modified to be hydrophobic. Thus, when the treatment solution supply step is performed, the substrate W is hydrophobic. The treatment solution supply step is performed on a substrate W that is hydrophobic. However, it is not limited to this. For example, when the treatment solution supply step is performed, the substrate W may be hydrophilic. For example, the treatment solution supply step may be performed on a substrate W that is hydrophilic. Modified embodiments will be described in detail below.

[0357] (19-1) Configuration of the modified embodiment The general overview of the substrate processing apparatus 1 and the configuration of the processing liquid generation unit 20 are substantially the same as those of the first embodiment in this modified embodiment. The configuration of the processing unit 11 in this modified embodiment will be described below. Figure 25 shows the configuration of the processing unit 11 and the processing liquid generation unit 20 in this modified embodiment. Note that components identical to those in the first embodiment are denoted by the same reference numerals, and detailed explanations are omitted.

[0358] The processing unit 11 includes a supply unit 15g in addition to the supply units 15a-15e. The supply unit 15g supplies a hydrophilic agent to the substrate W. The supply unit 15g supplies a hydrophilic agent to the substrate W held by the substrate holding unit 13. The hydrophilic agent is, for example, SC1. SC1 is a mixture of ammonia, hydrogen peroxide, and deionized water. SC1 is also called "APM" or "ammonia hydrogen peroxide mixture".

[0359] The supply unit 15g comprises a nozzle 16g, piping 17g, and a valve 18g. The nozzle 16g is installed inside the housing 12. The nozzle 16g discharges the hydrophilic agent. The piping 17g is connected to the nozzle 16g. The valve 18g is provided in the piping 17g. The valve 18g controls the supply of the hydrophilic agent.

[0360] The supply unit 15g is connected to the hydrophilic agent supply source 19g. The supply unit 15g communicates with the hydrophilic agent supply source 19g. The hydrophilic agent supply source 19g is connected, for example, to piping 17g. The hydrophilic agent supply source 19g delivers the hydrophilic agent to the supply unit 15g.

[0361] (19-2) Example of operation of a modified embodiment Figure 26 is a flowchart showing the procedure of the substrate processing method of this modified embodiment. The substrate processing method of this modified embodiment comprises steps S1, S11-S12, and S14-S18 described in the first embodiment. The substrate processing method of this modified embodiment further comprises steps S31-S33 instead of step S13 described in the first embodiment. Steps S31-S33 are performed after step S12. Steps S31-S33 are performed before step S14. The operations of steps S1, S11-S12, and S14-S18 are substantially the same between the first embodiment and this modified embodiment. For this reason, the operation of steps S1, S11, and S16-S18 will be omitted. The operation of steps S12, S31-S33, S14, and S15 will be described.

[0362] Step S12: Chemical solution supply process The supply unit 15b supplies a chemical solution to the substrate W. The chemical solution is supplied to the upper surface W1 of the substrate W. For example, the substrate W is etched by the chemical solution. Then, the supply unit 15b stops supplying the chemical solution to the substrate W.

[0363] If the chemical solution is hydrofluoric acid, the solution terminates the upper surface W1 of the substrate W with hydrogen. For example, the hydrogen bonds with atoms located on the upper surface W1 of the substrate W (e.g., silicon atoms). Thus, the substrate W is modified to be hydrophobic.

[0364] Hydrofluoric acid is equivalent to a hydrophobic agent. The chemical solution contains, for example, a hydrophobic agent.

[0365] Step S31: First rinse fluid supply process The first rinsing solution supply step is performed after the chemical solution supply step. The supply unit 15c supplies the rinsing solution to the substrate W. The rinsing solution is supplied to the upper surface W1 of the substrate W. For example, the substrate W is cleaned with the rinsing solution. For example, the chemical solution is removed from the substrate W with the rinsing solution. Then, the supply unit 15c stops supplying the rinsing solution to the substrate W.

[0366] Even after the first rinse solution supply process, the substrate W is still terminated with hydrogen. Therefore, even after the first rinse solution supply process, the substrate W remains hydrophobic.

[0367] Step S32: Hydrophilization process The supply unit 15g supplies hydrophilic agent to the substrate W. Specifically, the valve 18g opens. The nozzle 16g discharges the hydrophilic agent. The hydrophilic agent is supplied to the upper surface W1 of the substrate W. The hydrophilic agent removes the rinse liquid from the substrate W. This replaces the rinse liquid on the substrate W with the hydrophilic agent. Then, the supply unit 15g stops supplying the hydrophilic agent to the substrate W. Specifically, the valve 18g closes. The nozzle 16g stops discharging the replacement liquid.

[0368] The hydrophilic agent terminates the upper surface W1 of the substrate W with a hydroxyl group. For example, the hydroxyl group bonds to an atom (e.g., a silicon atom) located on the upper surface W1 of the substrate W. Thus, the substrate W is modified from hydrophobic to hydrophilic. For example, the affinity between the substrate W and water at the end of the hydrophilization process is higher than the affinity between the substrate W and water at the end of the chemical supply process.

[0369] When the hydrophilic agent is SC1, SC1 forms an oxide film on the upper surface W1 and forms hydroxyl groups on the oxide film.

[0370] Step S33: Second rinse fluid supply process The supply unit 15c supplies rinsing liquid to the substrate W. The rinsing liquid is supplied to the upper surface W1 of the substrate W. For example, the substrate W is cleaned with the rinsing liquid. For example, the hydrophilic agent is removed from the substrate W with the rinsing liquid. Then, the supply unit 15c stops supplying rinsing liquid to the substrate W.

[0371] Even after the second rinse solution supply step, the substrate W is still terminated by hydroxyl groups. Therefore, even after the second rinse solution supply step, the substrate W remains hydrophilic.

[0372] Step S14: Replacement fluid supply process The supply unit 15d supplies replacement liquid to the substrate W. The replacement liquid is supplied to the upper surface W1 of the substrate W. The replacement liquid removes the rinse liquid from the substrate W. This replaces the rinse liquid on the substrate W with the replacement liquid. Then, the supply unit 15d stops supplying replacement liquid to the substrate W.

[0373] Even after the displacement solution supply step, the substrate W is still terminated by hydroxyl groups. Therefore, even after the displacement solution supply step, the substrate W remains hydrophilic.

[0374] Step S15: Processing liquid supply process The supply unit 15a supplies the processing liquid to the substrate W. The supply unit 15a supplies the processing liquid to the hydrophilic substrate W. The processing liquid removes the replacement liquid from the substrate W. This replaces the replacement liquid on the substrate W with the processing liquid. Then, the supply unit 15a stops supplying the processing liquid to the substrate W.

[0375] (19-3) Technical significance of compound a The technical significance of compound a as a sublimable substance is explained by experimental examples 5a and 5b and comparative examples 1a, 1b, 2a, 2b, 3a, 3b, 4a, 4b, 5a, 6a, and 7a.

[0376] Three substrates W were prepared: a first substrate Wa, a second substrate Wb, and a third substrate Wc. Each of the first to third substrates Wa-Wc has a pattern P. The pattern P of the first substrate Wa is different from the pattern P of the second substrate Wb. The pattern P of the first substrate Wa is different from the pattern P of the third substrate Wc. The pattern P of the second substrate Wb is different from the pattern P of the third substrate Wc. The pattern P of the first substrate Wa is more prone to tipping over than the pattern P of the second substrate Wb. The pattern P of the second substrate Wb is more prone to tipping over than the pattern P of the third substrate Wc. The pattern P of the first substrate Wa is more prone to tipping over than the pattern P of the third substrate Wc.

[0377] Experimental examples 5a and 5b are performed under the following conditions. In experimental examples 5a and 5b, the second substrate Wb is used as substrate W.

[0378] Experimental example 5a involves performing a series of processes on the substrate W, including a chemical solution supply process, a rinse solution supply process, a replacement solution supply process, a processing solution supply process, a solidified film formation process, and a sublimation process.

[0379] The chemical solution supply process uses a hydrophobic agent as the chemical solution. The hydrophobic agent is hydrofluoric acid. Hydrofluoric acid is a mixture of hydrogen fluoride and deionized water. The volume ratio of hydrogen fluoride to deionized water is as follows: Hydrogen fluoride:Deionized water = 1:10 (volume ratio)

[0380] The rinsing solution supply process uses deionized water (DIW) as the rinsing solution.

[0381] The displacement solution supply process uses isopropyl alcohol as the displacement solution.

[0382] The processing solution supply process uses a processing solution consisting of a sublimable substance and a solvent. The sublimable substance is pinacolin oxime. The solvent is isopropyl alcohol (IPA). The volume ratio of the sublimable substance to the solvent is as follows: Sublimable substance:solvent = 1:30 (volume ratio) In other words, the volume ratio RV of the sublimable substance to the solvent is 3.3 [Vol%].

[0383] In the solidification film formation process, the substrate W is rotated at a rotational speed of 1500 rpm.

[0384] In the sublimation process, the substrate W is rotated at a rotational speed of 1500 rpm while the first gas is supplied to the substrate W.

[0385] As described above, the substrate W is hydrophobic during the processing liquid supply process. That is, the surface state of the substrate W during the processing liquid supply process is hydrophobic. The subscript "a" in Experimental Example 5a indicates that the surface state of the substrate W during the processing liquid supply process is hydrophobic.

[0386] Experimental Example 5b involves performing a series of processes on the substrate W, including a chemical solution supply step, a first rinse solution supply step, a hydrophilization step, a second rinse solution supply step, a displacement solution supply step, a treatment solution supply step, a solidification film formation step, and a sublimation step. The conditions for the chemical solution supply step, displacement solution supply step, treatment solution supply step, solidification film formation step, and sublimation step are the same for Experimental Example 5b as for Experimental Example 5a.

[0387] The first rinse solution supply step uses deionized water (DIW) as the rinse solution.

[0388] The hydrophilization process uses SC1 as a hydrophilic agent. SC1 is a mixture of ammonia, hydrogen peroxide, and deionized water. The volume ratios of ammonia, hydrogen peroxide, and deionized water are as follows: Ammonia:Hydrogen peroxide:Deionized water = 1:8:60 (by volume)

[0389] The second rinse solution supply process uses deionized water (DIW) as the rinse solution.

[0390] As described above, the substrate W is hydrophilic during the processing liquid supply process. That is, the surface state of the substrate W during the processing liquid supply process is hydrophilic. The subscript "b" in Experimental Example 5b indicates that the surface state of the substrate W during the processing liquid supply process is hydrophilic.

[0391] Comparative Examples 1a and 1b are performed under the following conditions. Comparative Examples 1a and 1b each use the third substrate Wc as substrate W. In the processing solution supply step of Comparative Examples 1a and 1b, the processing solution consists of a sublimable substance and a solvent. In Comparative Examples 1a and 1b, the sublimable substance is cyclohexanone oxime. In Comparative Examples 1a and 1b, the solvent is isopropyl alcohol (IPA). In Comparative Examples 1a and 1b, the volume ratio of the sublimable substance to the solvent is as follows. Sublimable substance:solvent = 1:40 (volume ratio) In other words, the volume ratio RV of the sublimable substance to the solvent is 2.5 [Vol%]. All other conditions are the same for Comparative Example 1a as for Experimental Example 5a. All other conditions are the same for Comparative Example 1b as for Experimental Example 5b.

[0392] Comparative Examples 2a and 2b are carried out under the following conditions. Comparative Examples 2a and 2b each use the third substrate Wc as substrate W. In the processing solution supply step of Comparative Examples 2a and 2b, the processing solution consists of a sublimable substance and a solvent. In Comparative Examples 2a and 2b, the sublimable substance is cyclohexanone oxime. In Comparative Examples 2a and 2b, the solvent is methanol. In Comparative Examples 2a and 2b, the volume ratio of the sublimable substance to the solvent is as follows. Sublimable substance:solvent = 1:40 (volume ratio) In other words, the volume ratio RV of the sublimable substance to the solvent is 2.5 [Vol%]. All other conditions are the same for Comparative Example 2a as for Experimental Example 5a. All other conditions are the same for Comparative Example 2b as for Experimental Example 5b.

[0393] Comparative Examples 3a and 3b are carried out under the following conditions. Comparative Examples 3a and 3b each use the third substrate Wc as substrate W. In the processing solution supply step of Comparative Examples 3a and 3b, the processing solution consists of a sublimable substance and a solvent. In Comparative Examples 3a and 3b, the sublimable substance is camphor. In Comparative Examples 3a and 3b, the solvent is isopropyl alcohol. In Comparative Examples 3a and 3b, the volume ratio of the sublimable substance to the solvent is as follows. Sublimable substance:solvent = 1:110 (volume ratio) In other words, the volume ratio RV of the sublimable substance to the solvent is 0.91 [Vol%]. All other conditions are the same for Comparative Example 3a as for Experimental Example 5a. All other conditions are the same for Comparative Example 3b as for Experimental Example 5b.

[0394] Comparative Examples 4a and 4b are carried out under the following conditions. Comparative Examples 4a and 4b each use the third substrate Wc as substrate W. In the processing solution supply step of Comparative Examples 4a and 4b, the processing solution consists of a sublimable substance and a solvent. In Comparative Examples 4a and 4b, the sublimable substance is camphor. In Comparative Examples 4a and 4b, the solvent is methanol. In Comparative Examples 4a and 4b, the volume ratio of the sublimable substance to the solvent is as follows. Sublimable substance:solvent = 1:100 (volume ratio) In other words, the volume ratio RV of the sublimable substance to the solvent is 1.0 [Vol%]. All other conditions are the same for Comparative Example 4a as for Experimental Example 5a. All other conditions are the same for Comparative Example 4b as for Experimental Example 5b.

[0395] Comparative Example 5a is carried out under the following conditions. Comparative Example 5a uses the first substrate Wa as substrate W. In the processing solution supply step of Comparative Example 5a, the processing solution consists of a sublimable substance and a solvent. In Comparative Example 5a, the sublimable substance is cyclohexanone oxime. In Comparative Example 5a, the solvent is isopropyl alcohol. In Comparative Example 5a, the volume ratio of the sublimable substance to the solvent is as follows. Sublimable substance:solvent = 1:40 (volume ratio) In other words, the volume ratio RV of the sublimable substance to the solvent is 2.5 [Vol%]. All other conditions in Comparative Example 5a are the same as in Experimental Example 5a.

[0396] Comparative Example 6a is carried out under the following conditions. Comparative Example 6a uses the first substrate Wa as substrate W. In the processing solution supply step of Comparative Example 6a, the processing solution consists of a sublimable substance, a solvent, and an additive. In Comparative Example 6a, the sublimable substance is cyclohexanone oxime. In Comparative Example 6a, the solvent is isopropyl alcohol. In Comparative Example 6a, the additive is tert-butanol. Tert-butanol is also called TBA or tert-butyl alcohol. In Comparative Example 6a, the volume ratio of the sublimable substance to the solvent is as follows. Sublimable substance:solvent = 1:40 (volume ratio) In other words, the volume ratio RV of the sublimable substance to the solvent is 2.5 [Vol%]. In Comparative Example 6a, the volume ratio of the additive to the total volume of the sublimable substance and solvent is as follows. Additives:(Total of sublimable substance and solvent) = 10:100 (volume ratio) All other conditions are the same for Comparative Example 6a as for Experimental Example 5a.

[0397] Comparative Example 7a is carried out under the following conditions. Comparative Example 7a uses the first substrate Wa as substrate W. In the processing solution supply step of Comparative Example 7a, the processing solution consists of a sublimable substance, a solvent, and an additive. In Comparative Example 7a, the sublimable substance is cyclohexanone oxime. In Comparative Example 7a, the solvent is isopropyl alcohol. In Comparative Example 7a, the additive is tert-butanol. In Comparative Example 7a, the volume ratio of the sublimable substance to the solvent is as follows. Sublimable substance:solvent = 1:40 (volume ratio) In other words, the volume ratio RV of the sublimable substance to the solvent is 2.5 [Vol%]. In Comparative Example 7a, the volume ratio of the additive to the total volume of the sublimable substance and solvent is as follows. Additives:(Total of sublimable substance and solvent) = 1:100 (volume ratio) All other conditions are the same for Comparative Example 6a as for Experimental Example 5a.

[0398] Each substrate W processed in Experimental Examples 5a and 5b and Comparative Examples 1a, 1b, 2a, 2b, 3a, 3b, 4a, 4b, 5a, 6a, and 7a will be evaluated according to the following evaluation criteria. The observer will observe the pattern P at multiple measurement points on the substrate W. Based on the observed results, the collapse rate at each measurement point will be calculated. The collapse rate is as described in the evaluation criteria for Experimental Examples 1-4. Furthermore, the average collapse rate will be calculated based on the collapse rates at each measurement point. The average collapse rate is the sum of the multiple collapse rates divided by the number of measurement points.

[0399] Figure 27 is a table showing the evaluation of each substrate W treated in Experimental Examples 5a and 5b and Comparative Examples 1a, 1b, 2a, and 2b. Figure 28 is a table showing the evaluation of each substrate W treated in Comparative Examples 3a, 3b, 4a, 4b, 5a, 6a, and 7a.

[0400] In Experiment 5a, the average collapse rate was 0.02%. In Experiment 5b, the average collapse rate was 0.16%.

[0401] From experimental examples 5a and 5b, the following can be observed: When the sublimable substance is pinacolin oxime, the collapse of the pattern P is effectively suppressed regardless of whether the substrate W is hydrophobic or hydrophilic. When the sublimable substance is pinacolin oxime, the substrate is properly treated while protecting the pattern P, regardless of whether the surface state of the substrate W is hydrophobic or hydrophilic. When the sublimable substance is pinacolin oxime, the treatment quality of the substrate W is substantially independent of the surface state of the substrate W.

[0402] In Comparative Example 1a, the average collapse rate was 0.7%. In Comparative Example 1b, the average collapse rate was 78.6%. In Comparative Example 2a, the average collapse rate was 0.1%. In Comparative Example 2b, the average collapse rate was 100%.

[0403] From Comparative Examples 1a, 1b, 2a, and 2b, the following can be observed: When the sublimable substance is cyclohexanone oxime, the collapse of the pattern P on the hydrophobic substrate W is suitably suppressed. However, when the sublimable substance is cyclohexanone oxime, the pattern P on the hydrophilic substrate W collapses significantly. In other words, when the sublimable substance is cyclohexanone oxime, the processing quality of the substrate W is significantly dependent on the surface condition of the substrate W.

[0404] In Comparative Example 3a, the average collapse rate was 37.4%. In Comparative Example 3b, the average collapse rate was 100%. In Comparative Example 4a, the average collapse rate was 9.95%. In Comparative Example 4b, the average collapse rate was 100%. From Comparative Examples 3a, 3b, 4a, and 4b, the following can be observed: When the sublimable material is camphor, the collapse of the pattern P on the hydrophobic substrate W is suppressed. However, when the sublimable material is camphor, the pattern P on the hydrophilic substrate W collapses significantly. In other words, when the sublimable material is camphor, the processing quality of the substrate W is significantly dependent on the surface condition of the substrate W.

[0405] (19-4) Factors affecting the collapse rate The inventors investigated the factors that affect the collapse rate. As a result, the inventors inferred that the factor that affects the collapse rate is the interfacial free energy. The inventors' views on the factors that affect the collapse rate are explained below.

[0406] Figure 29 is a schematic enlarged view of the substrate W during the solidification film formation process. In the solidification film formation process, a liquid film H of the processing solution is formed on the substrate W. Hereinafter, the liquid film H of the processing solution will be referred to as "processing solution H" as appropriate. The substrate W is in contact with the processing solution H. Furthermore, in the solidification film formation process, a solidification film K is formed on the substrate W. The substrate W is in contact with the solidification film K. The solidification film K is in contact with the processing solution H.

[0407] When the solidified film K begins to form on the substrate W, a first interface, a second interface, and a third interface exist. The first interface is the interface between the substrate W and the processing liquid H. The second interface is the interface between the substrate W and the solidified film K. The third interface is the interface between the solidified film K and the processing liquid H.

[0408] The first interface has an interfacial free energy γWH. The second interface has an interfacial free energy γKW. The third interface has an interfacial free energy γHK.

[0409] The interfacial free energies γWH, γKW, and γHK are calculated through measurement and computation.

[0410] The measurement includes, for example, the measurement of the surface free energy of the processing solution H. The measurement of the surface free energy of the processing solution H is performed, for example, by the suspension method. The measurement includes, for example, the measurement of the contact angle between the first reference solution and the substrate W, and the measurement of the contact angle between the second reference solution and the substrate W. The measurement includes, for example, the measurement of the contact angle between the first reference solution and the solidified film K, and the measurement of the contact angle between the second reference solution and the solidified film K. Here, the surface free energy of the first reference solution is known. Specifically, the surface free energy of the first reference solution, the dispersion component of the surface free energy of the first reference solution, and the polar component of the surface free energy of the first reference solution are all known. Similarly, the surface free energy of the second reference solution is known. Specifically, the surface free energy of the second reference solution, the dispersion component of the surface free energy of the second reference solution, and the polar component of the surface free energy of the second reference solution are all known.

[0411] The calculations are performed based on the measurement results described above. Specifically, the calculations are performed based on the measurement results described above and the known surface free energy. The calculations are performed using, for example, Young's equation, Dupre's equation, and the extended Fowkes equation. The calculations are performed by substituting the measurement results into these equations. The calculations are performed by substituting the measurement results and the known surface free energy into these equations. The interfacial free energies γWH, γKW, and γHK are obtained through these calculations.

[0412] Furthermore, the angle θ is defined by the interfacial free energies γWH, γKW, and γHK. Specifically, the angle θ is defined by equation (1). cosθ=(γWH-γKW) / γHK (1)

[0413] The angle θ is a concept similar to the contact angle.

[0414] The inventors determined the angle θ in experimental examples 5a and 5b and comparative examples 1a, 1b, 2a, 2b, 3a, 3b, 4a, 4b, 5a, 6a, and 7a.

[0415] The tables in Figures 27 and 28 show the angles θ for experimental examples 5a and 5b and comparative examples 1a, 1b, 2a, 2b, 3a, 3b, 4a, 4b, 5a, 6a, and 7a, respectively. Figure 30 is a graph showing the relationship between angle θ and the average collapse rate.

[0416] Each angle θ takes values ​​from 24.7 degrees to 95.5 degrees. The average collapse rate takes values ​​from 0.02% to 100%. When the angle θ is 72.6 degrees or less, the average collapse rate is 37.4% or less. When the angle θ is 83.2 degrees or more, the average collapse rate is 78.6% or more. Therefore, the average collapse rate when the angle θ is 72.6 degrees or less is lower than the average collapse rate when the angle θ is 83.2 degrees or more.

[0417] Therefore, it can be said that the average collapse rate is appropriately reduced when the angle θ is 70 degrees or less. The angle θ is presumed to be one of the factors that influence the average collapse rate.

[0418] (19-5) Mechanism of collapse in pattern P As described above, in Comparative Examples 1b, 2b, 3b, and 4b, pattern P collapsed significantly. In Comparative Examples 1b, 2b, 3b, and 4b, the angle θ was large. Therefore, the inventors hypothesized the following mechanism for the collapse of pattern P when the angle θ is large.

[0419] Figures 31, 32, 33, and 34 are diagrams illustrating the collapse mechanism of pattern P, respectively. Figures 31, 32, and 33 are schematic diagrams showing the substrate W during the solidification film formation process, respectively. Figure 34 is a schematic diagram showing the substrate W during the sublimation process.

[0420] Refer to Figure 31. In the solidification film formation process, the sublimable substance changes from solute in the processing liquid to a solid. The solid sublimable substance corresponds to the solidified film K. When the solidified film K begins to form, it has, for example, a granular shape. The solidified film K is deposited, for example, on the substrate W. Here, the angle θ is large. Therefore, the solidified film K is deposited non-uniformly on the substrate W. For example, the solidified film K is deposited only on the upper part of the protrusion W2. For example, the solidified film K is not deposited on the lower part of the protrusion W2.

[0421] Refer to Figure 32. The solidified film K grows. The solidified film K becomes larger. Here, the angle θ is large. Therefore, the solidified film K grows non-uniformly. For example, the solidified film K grows only in the vicinity of the upper part of the protrusion W2. For example, the solidified film K does not grow in the vicinity of the lower part of the protrusion W2.

[0422] Refer to Figure 33. The solidified film K grows further. The solidified film K becomes larger. Here, the angle θ is large. Therefore, the solidified film K grows unevenly. For example, the solidified film K grows near the top of the protrusion W2. For example, the solidified film K does not grow near the bottom of the protrusion W2. For example, the solidified film K covers only a part of the top surface W1 of the substrate W. For example, the solidified film K does not cover the entire top surface W1 of the substrate W.

[0423] Furthermore, the thickness of the solidified film K becomes non-uniform. The solidified film K has an upper surface K1. For example, the upper surface K1 is inclined.

[0424] Figure 33 schematically shows the substrate W at the end of the solidification film formation process. For example, even at the end of the solidification film formation process, the solidified film K does not fill all of the recesses A. For example, even at the end of the solidification film formation process, the recesses A are not filled with the solidified film K. For example, even at the end of the solidification film formation process, the liquid film H of the processing solution still remains in the recesses A.

[0425] Refer to Figure 34. The solidified film K sublimes. After the solidified film K sublimes, the protrusion W2 is no longer supported by the solidified film K. Even after the solidified film K sublimes, the liquid film H of the treatment solution still exists in the recess A. The treatment solution (e.g., the liquid film H of the treatment solution) acts a significant force on the protrusion W2. The protrusion W2 is subjected to a significant force. A significant force is, for example, the surface tension of the treatment solution L. A significant force is, for example, capillary force. As a result, the protrusion W2 collapses.

[0426] In summary, in comparative examples 1b, 2b, 3b, and 4b, the angle θ is large. Therefore, during the solidification film formation process, the solidified film K precipitates unevenly. During the solidification film formation process, the solidified film K grows unevenly. Consequently, at the end of the solidification film formation process, the processing liquid remains in the recess A. Therefore, the pattern P collapses.

[0427] (19-6) Protection mechanism of pattern P As described above, in experimental examples 5a and 5b, the collapse of pattern P was suppressed. In experimental examples 5a and 5b, the angle θ was small. Therefore, the inventors hypothesized the following mechanism for protecting pattern P when the angle θ is small.

[0428] Figures 35, 36, 37, and 38 illustrate the protection mechanism of pattern P, respectively. Figures 35, 36, and 37 schematically show the substrate W during the solidification film formation process, respectively. Figure 38 schematically shows the substrate W during the sublimation process.

[0429] Refer to Figure 35. The solidified film K is deposited on the substrate W. Here, the angle θ is small. Therefore, the solidified film K is deposited uniformly on the substrate W. For example, the solidified film K is deposited uniformly over the entire upper surface W1. For example, the solidified film K is deposited uniformly over the entire protrusion W2. For example, the solidified film K is deposited not only on the upper part of the protrusion W2 but also on the lower part of the protrusion W2.

[0430] Refer to Figure 36. The solidified film K grows. The solidified film K becomes larger. Here, the angle θ is small. Therefore, the solidified film K grows uniformly. For example, the solidified film K grows not only near the upper part of the protrusion W2 but also near the lower part of the protrusion W2. For example, the solidified film K covers the entire upper surface W1 of the substrate W.

[0431] Refer to Figure 37. The solidified film K grows further. The solidified film K becomes even larger. Here, the angle θ is small. Therefore, the solidified film K grows uniformly. For example, the solidified film K grows not only near the upper part of the protrusion W2 but also near the lower part of the protrusion W2.

[0432] Furthermore, the thickness of the solidified film K is uniform. For example, the upper surface K1 of the solidified film K is not tilted. For example, the upper surface K1 is horizontal.

[0433] Figure 37 schematically shows the substrate W at the end of the solidification film formation process. For example, at the end of the solidification film formation process, the solidification film K fills the entire recess A. For example, at the end of the solidification film formation process, the recess A is filled with the solidification film K. For example, at the end of the solidification film formation process, the processing liquid (e.g., the liquid film H of the processing liquid) does not remain in the recess A. For example, at the end of the solidification film formation process, the processing liquid (e.g., the liquid film H of the processing liquid) is not present in the recess A.

[0434] Refer to Figure 38. The solidified film K sublimes. The processing liquid (e.g., the liquid film H of the processing liquid) is not present in the recess A. The protrusion W2 is not subjected to any significant force. Therefore, the protrusion W2 does not collapse.

[0435] In summary, in experimental examples 5a and 5b, the angle θ is small. Therefore, during the solidification film formation process, the solidification film K precipitates uniformly. During the solidification film formation process, the solidification film K grows uniformly. Consequently, at the end of the solidification film formation process, no processing liquid remains in the recess A. Therefore, pattern P is protected.

[0436] (20) The first to third embodiments and the modified embodiments described in (1) to (19) above may be further modified as appropriate by substituting or combining each component with the components of other modified embodiments. [Explanation of symbols]

[0437] 1 ... Substrate processing equipment 10 ... Control Unit 11… Processing Unit 13... Board holding part 15a ... Supply unit (processing liquid supply unit) 15e ... Supply Department (First Gas Supply Department) 15f … Supply Department (Second Gas Supply Department) 16a ... Nozzle (processing liquid nozzle) 16e ... Nozzle (First gas nozzle) 16f ... Nozzle (Second gas nozzle) 20 … Processing liquid generation unit 21 … tank 41 … Heating section 42 … Heating section 43… Resistance heater 54 … Mixing section H…Liquid film K... Solidified film Ka... First solidification film Kb…Second solidified film MP… Melting point of sublimable substances Q1… Flow rate of the first gas in the sublimation process Q2… Flow rate of the second gas in the removal process T1 ... Temperature of the first gas in the sublimation process T2 ... Temperature of the second gas during the removal process The temperature of the substrate during the removal process. v1 … Substrate rotation speed in the sublimation process v2 … Rotation speed of the substrate during the removal process W… Circuit board W1 ... Top surface of the circuit board W1a … Pattern formation region W1b … Area without pattern formation P... Pattern W2… protruding part A... recessed W3…Bottom surface

Claims

1. A substrate processing method for processing a substrate, The substrate has an upper surface that includes a pattern-forming region where a pattern is formed and a pattern-non-forming region where the pattern is not formed. A processing liquid supply step involves supplying a processing liquid containing a sublimable substance and a solvent to the upper surface of the substrate to form a liquid film of the processing liquid on the upper surface of the substrate, A solidification film formation step of evaporating the solvent from the liquid film to form a solidified film containing the sublimable substance on the upper surface of the substrate, the solidified film having a first solidified film located on the pattern-forming region and a second solidified film located on the non-pattern-forming region. A sublimation step in which a first gas is blown toward the first solidified film to sublimate the first solidified film, A removal step of removing the second solidified film from the substrate, Equipped with, The removal step involves blowing a second gas toward the second solidified film. The flow rate of the second gas is greater than the flow rate of the first gas. Substrate processing method.

2. A substrate processing method for processing a substrate, The substrate has an upper surface that includes a pattern-forming region where a pattern is formed and a pattern-non-forming region where the pattern is not formed. A processing liquid supply step involves supplying a processing liquid containing a sublimable substance and a solvent to the upper surface of the substrate to form a liquid film of the processing liquid on the upper surface of the substrate, A solidification film formation step of evaporating the solvent from the liquid film to form a solidified film containing the sublimable substance on the upper surface of the substrate, the solidified film having a first solidified film located on the pattern-forming region and a second solidified film located on the non-pattern-forming region. A sublimation step in which a first gas is blown toward the first solidified film to sublimate the first solidified film, A removal step of removing the second solidified film from the substrate, Equipped with, The removal step involves blowing a second gas toward the second solidified film. The second gas has a temperature higher than the temperature of the first gas. Substrate processing method.

3. A substrate processing method for processing a substrate, The substrate has an upper surface that includes a pattern-forming region where a pattern is formed and a pattern-non-forming region where the pattern is not formed. A processing liquid supply step involves supplying a processing liquid containing a sublimable substance and a solvent to the upper surface of the substrate to form a liquid film of the processing liquid on the upper surface of the substrate, A solidification film formation step of evaporating the solvent from the liquid film to form a solidified film containing the sublimable substance on the upper surface of the substrate, the solidified film having a first solidified film located on the pattern-forming region and a second solidified film located on the non-pattern-forming region. A sublimation step in which a first gas is blown toward the first solidified film to sublimate the first solidified film, A removal step of removing the second solidified film from the substrate, Equipped with, The removal step involves blowing a second gas toward the second solidified film. The second gas has a temperature higher than the melting point of the sublimable substance. Substrate processing method.

4. A substrate processing method for processing a substrate, The substrate has an upper surface that includes a pattern-forming region where a pattern is formed and a pattern-non-forming region where the pattern is not formed. A processing liquid supply step involves supplying a processing liquid containing a sublimable substance and a solvent to the upper surface of the substrate to form a liquid film of the processing liquid on the upper surface of the substrate, A solidification film formation step of evaporating the solvent from the liquid film to form a solidified film containing the sublimable substance on the upper surface of the substrate, the solidified film having a first solidified film located on the pattern-forming region and a second solidified film located on the non-pattern-forming region. A sublimation step in which a first gas is blown toward the first solidified film to sublimate the first solidified film, A removal step of removing the second solidified film from the substrate, Equipped with, The removal step involves blowing a second gas toward the second solidified film. The removal process does not blow the second gas toward the pattern formation region. Substrate processing method.

5. A substrate processing method according to any one of claims 1 to 4, The removal step involves heating the second solidified film with the second gas. Substrate processing method.

6. A substrate processing method for processing a substrate, The substrate has an upper surface that includes a pattern-forming region where a pattern is formed and a pattern-non-forming region where the pattern is not formed. A processing liquid supply step involves supplying a processing liquid containing a sublimable substance and a solvent to the upper surface of the substrate to form a liquid film of the processing liquid on the upper surface of the substrate, A solidification film formation step of evaporating the solvent from the liquid film to form a solidified film containing the sublimable substance on the upper surface of the substrate, the solidified film having a first solidified film located on the pattern-forming region and a second solidified film located on the non-pattern-forming region. A sublimation step in which a first gas is blown toward the first solidified film to sublimate the first solidified film, A removal step of removing the second solidified film from the substrate, Equipped with, The removal step involves heating the second solidified film, After the entirety of the first solidified film has sublimated, the second solidified film is heated. Substrate processing method.

7. A substrate processing method for processing a substrate, The substrate has an upper surface that includes a pattern-forming region where a pattern is formed and a pattern-non-forming region where the pattern is not formed. A processing liquid supply step involves supplying a processing liquid containing a sublimable substance and a solvent to the upper surface of the substrate to form a liquid film of the processing liquid on the upper surface of the substrate, A solidification film formation step of evaporating the solvent from the liquid film to form a solidified film containing the sublimable substance on the upper surface of the substrate, the solidified film having a first solidified film located on the pattern-forming region and a second solidified film located on the non-pattern-forming region. A sublimation step in which a first gas is blown toward the first solidified film to sublimate the first solidified film, A removal step of removing the second solidified film from the substrate, Equipped with, The removal step involves heating the second solidified film, In the sublimation process, the substrate is not heated. Substrate processing method.

8. A substrate processing method according to claim 6 or 7, The removal step involves heating the pattern-free region and heating the second solidified film through the pattern-free region. Substrate processing method.

9. A substrate processing method according to claim 8, The removal step involves heating the pattern-unformed region to a temperature higher than the temperature of the first gas. Substrate processing method.

10. A substrate processing method according to any one of claims 6 to 9, The removal process involves heating the lower surface of the substrate. Substrate processing method.

11. A substrate processing method according to any one of claims 6 to 10, The removal step involves heating the second solidified film with at least one of a high-temperature fluid, a resistance heater, and a lamp heater. Substrate processing method.

12. A substrate processing method for processing a substrate, The substrate has an upper surface that includes a pattern-forming region where a pattern is formed and a pattern-non-forming region where the pattern is not formed. A processing liquid supply step involves supplying a processing liquid containing a sublimable substance and a solvent to the upper surface of the substrate to form a liquid film of the processing liquid on the upper surface of the substrate, A solidification film formation step of evaporating the solvent from the liquid film to form a solidified film containing the sublimable substance on the upper surface of the substrate, the solidified film having a first solidified film located on the pattern-forming region and a second solidified film located on the non-pattern-forming region. A sublimation step in which a first gas is blown toward the first solidified film to sublimate the first solidified film, A removal step of removing the second solidified film from the substrate, Equipped with, The sublimable substance comprises at least one of pinacolin oxime, acetophenone oxime, cyclopentanone oxime, and 4-tert-butylphenol. Substrate processing method.

13. A substrate processing method according to any one of claims 1 to 12, The removal process begins after the sublimation process is completed. Substrate processing method.

14. A substrate processing method according to any one of claims 1 to 12, The period during which the removal process is performed overlaps with at least a portion of the period during which the sublimation process is performed. Substrate processing method.

15. A substrate processing method according to claim 14, After the sublimation process has started, the removal process begins. Substrate processing method.

16. A substrate processing method according to any one of claims 1 to 15, The removal step involves changing the second solidified film into a gas phase. Substrate processing method.

17. A substrate processing method according to any one of claims 1 to 16, The vapor pressure of the sublimable substance at room temperature is 100 Pa or less. Substrate processing method.

18. A substrate processing method for processing a substrate on which a pattern has been formed, A processing solution supply step involves supplying a processing solution containing a sublimable substance and a solvent to a substrate, A solidification film formation step involves evaporating the solvent from the processing liquid on the substrate to form a solidified film containing the sublimable substance on the substrate, A sublimation step for sublimating the solidified film, Equipped with, The sublimable substance comprises at least one of pinacolin oxime, acetophenone oxime, cyclopentanone oxime, and 4-tert-butylphenol. Substrate processing method.

19. A processing liquid used for processing a substrate on which a pattern has been formed, The aforementioned processing liquid is Sublimable substances and Solvent and, Includes, The processing liquid is supplied to the substrate, the solvent evaporates from the processing liquid on the substrate, a solidified film containing the sublimable substance is formed on the substrate, and then the solidified film sublimes. The sublimable substance comprises at least one of pinacolin oxime, acetophenone oxime, cyclopentanone oxime, and 4-tert-butylphenol. Processing liquid.

20. The processing solution according to claim 19, The solvent is isopropyl alcohol. Processing liquid.

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