Substrate processing method

Abstract

A substrate processing method according to the present invention comprises: a drying pretreatment liquid supply step in which a drying pretreatment liquid, which is a solution in which a sublimable substance is dissolved in a solvent, is supplied to the upper surface of a substrate on which a pattern is formed, and a liquid film of the drying pretreatment liquid is formed on the upper surface of the substrate; a precipitation step in which a solid of the sublimable substance is precipitated on the upper surface of the substrate by evaporating the solvent from the liquid film; a film thickness reduction rate measurement step for measuring a film thickness reduction rate, which is the rate at which the thickness of the liquid film is reduced by evaporation of the solvent, prior to solid precipitation of the sublimable substance in the precipitation step; a reduction speed determination step for determining whether the film thickness reduction speed measured in the film thickness reduction speed measurement step is within a reference speed range; and a sublimation step for sublimating the solid of the sublimable substance after the deposition step is completed when the film thickness reduction rate is determined to be within the reference concentration range in the reduction rate determination step.

Description

[0001] This application is a divisional application of the original application, with the application date of November 25, 2019, the application number 201980086789.8, and the invention name of "Substrate processing method and substrate processing device". Technical Field

[0002] The present invention relates to a substrate processing method and a substrate processing device for processing a substrate. The substrate includes, for example, a semiconductor wafer, a liquid crystal display device or an organic EL (electroluminescence) display device, a FPD (Flat Panel Display) substrate, an optical disk substrate, a magnetic disk substrate, a magneto-optical disk substrate, a photomask substrate, a ceramic substrate, a solar cell substrate, etc. Background Art

[0003] In the manufacturing process of semiconductor devices, FPDs, etc., substrates such as semiconductor wafers and glass substrates for FPDs are processed as needed. Such processing includes supplying a processing liquid such as a chemical solution or a rinse liquid to the substrate. After the processing liquid is supplied, the processing liquid is removed from the substrate and the substrate is dried. In a single-wafer substrate processing device that processes substrates one by one, spin drying is performed, that is, the liquid on the substrate is removed by high-speed rotation of the substrate to dry the substrate.

[0004] When a pattern is formed on the surface of the substrate, when the substrate is dried, sometimes the force generated by the surface tension of the treatment liquid attached to the substrate is applied to the pattern, causing the pattern to collapse. As a countermeasure, the following method is adopted: a liquid with a low surface tension such as IPA (isopropyl alcohol) is supplied to the substrate, or a hydrophobic agent that makes the contact angle of the liquid relative to the pattern close to 90 degrees is supplied to the substrate. However, even if IPA and a hydrophobic agent are used, the collapse force that collapses the pattern is not zero. Therefore, depending on the strength of the pattern, there is a situation where the collapse of the pattern cannot be fully prevented even if these countermeasures are taken.

[0005] In recent years, as a technology to prevent the pattern from being damaged, sublimation drying has attracted attention. For example, a substrate processing method and a substrate processing device for performing sublimation drying are disclosed in Patent Document 1. In the sublimation drying described in Patent Document 1, a solution of a sublimable substance is supplied to the upper surface of the substrate, and the DIW (deionized water) on the substrate is replaced with a solution of the sublimable substance. Thereafter, the solvent of the sublimable substance is evaporated, and the sublimable substance is precipitated. Accordingly, a film of the sublimable substance containing a solid is formed on the upper surface of the substrate. Thereafter, the substrate is heated. Accordingly, the sublimable substance on the substrate sublimates and is removed from the substrate.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2012-243869 Summary of the invention

[0009] Problem that the invention aims to solve

[0010] Generally speaking, sublimation drying has a lower pattern failure rate than conventional drying methods such as spin drying that utilizes high-speed rotation of the substrate to remove liquid, and IPA drying that uses IPA. However, if the strength of the pattern is extremely low, there is a situation where the pattern failure cannot be fully prevented even if sublimation drying is implemented. According to the research of the inventors of the present application, one of the reasons is the thickness of the film containing the solid sublimable substance.

[0011] The thickness of the solid of sublimable substance corresponds to the thickness of the solution of sublimable substance when reaching the saturation concentration of sublimable substance.As long as the concentration of the sublimable substance in the solution of sublimable substance can be known before reaching the saturation concentration of sublimable substance, the thickness of the solid of sublimable substance can be predicted, and the solid of sublimable substance avoiding forming inappropriate thickness is avoided.

[0012] Generally, in order to measure the concentration of a substance in a liquid, it is necessary to bring the concentration measuring instrument into contact with the liquid. Since the solution of the sublimable substance formed on the substrate is relatively thin, it is difficult to bring the concentration measuring instrument into contact with the liquid film without contacting the upper surface of the substrate. Therefore, there is a risk that the pattern may be damaged and collapsed due to contact with the concentration measuring instrument.

[0013] Therefore, one of the objects of the present invention is to provide a substrate processing method and a substrate processing apparatus, which can reduce the failure rate of a pattern that occurs when a sublimable substance is removed from the upper surface of a substrate by sublimation.

[0014] Technical solutions to the problem

[0015] One embodiment of the present invention provides a substrate processing method, which includes: a drying pre-treatment liquid supplying step, in which a solution formed by dissolving a sublimable substance in a solvent, that is, a drying pre-treatment liquid, is supplied to the upper surface of a substrate formed with a pattern, and a liquid film of the drying pre-treatment liquid is formed on the upper surface of the substrate; a precipitation step, in which the solid of the sublimable substance is precipitated on the upper surface of the substrate by evaporating the solvent from the liquid film; a concentration determination step, in which, before the solid of the sublimable substance is precipitated in the precipitation step, based on the speed at which the thickness of the liquid film decreases due to the evaporation of the solvent, that is, the film thickness reduction speed, whether the concentration of the sublimable substance in the liquid film is within a reference concentration range; and a sublimation step, in which, when it is determined in the concentration determination step that the concentration of the sublimable substance in the liquid film is within the reference concentration range, the solid of the sublimable substance is sublimated after the precipitation step is completed.

[0016] According to this method, the solution formed by dissolving the sublimable substance in the solvent is supplied to the upper surface of the substrate. Accordingly, the liquid film of the drying pre-treatment liquid is formed on the upper surface of the substrate. Thereafter, the solvent is evaporated from the liquid film of the drying pre-treatment liquid. The concentration of the sublimable substance in the liquid film of the drying pre-treatment liquid rises along with the evaporation of the solvent. If the concentration of the sublimable substance reaches the saturation concentration of the sublimable substance, the solid of the sublimable substance is separated out in the liquid film of the drying pre-treatment liquid.

[0017] The inventor of the present application etc. has found that there is a correlation between the film thickness reduction speed and the concentration of the sublimation substance in the liquid film. Therefore, if the reduction speed based on the thickness of the liquid film of the dry pre-treatment liquid in the precipitation process determines whether the concentration of the sublimation substance in the liquid film is within the reference concentration range, then before the solid of the above-mentioned sublimation substance is precipitated, that is, before the concentration of the sublimation substance reaches the saturation concentration of the sublimation substance, it is possible to determine whether the concentration of the sublimation substance in the liquid film is within the reference concentration range. When determining that the concentration of the sublimation substance in the liquid film is within the reference concentration range, the solid of the sublimation substance of appropriate thickness is formed. And, owing to make the solid of the sublimation substance sublime after the precipitation process ends, the substrate having reduced the failure rate of the pattern can be obtained.

[0018] On the other hand, when the concentration of the sublimable substance in the judgment liquid film is not within the scope of the reference concentration, if the substrate processing is interrupted, the situation of the solid sublimation of the sublimable substance of inappropriate thickness can be prevented before it happens. Accordingly, the rise of the failure rate of the pattern can be suppressed.

[0019] In one embodiment of the present invention, the concentration determination process includes the following process: by comparing the previously measured reference data with the film thickness reduction rate measured in the precipitation process, the concentration of the sublimable substance in the liquid film is estimated. Therefore, in the precipitation process, the concentration of the sublimable substance in the liquid film can be easily estimated.

[0020] In one embodiment of the present invention, the substrate processing method further includes a drying pre-treatment liquid removal step, wherein when it is determined in the concentration determination step that the concentration of the sublimable substance in the liquid film is not within the reference concentration range, the drying pre-treatment liquid is removed from the upper surface of the substrate by supplying a removal liquid to the upper surface of the substrate before the solid of the sublimable substance is precipitated in the precipitation step.

[0021] According to this method, when the concentration of the sublimable substance in the liquid film is not within the range of the reference concentration, before the solid of the sublimable substance precipitates, the sublimable substance can be removed from the upper surface of the substrate by removing the liquid. Accordingly, the situation of the solid of the sublimable substance with inappropriate thickness formed on the upper surface of the substrate can be prevented before it happens. Accordingly, the rise of the failure rate of the pattern can be suppressed. In addition, since the dry pre-treatment liquid on the upper surface of the substrate is removed, the substrate can be reused.

[0022] In one embodiment of the present invention, the substrate processing method further includes a solvent evaporation promotion step, which is to promote the evaporation of the solvent from the liquid film during the execution of the precipitation step when the concentration of the sublimable substance in the liquid film is determined to be lower than the lower limit of the reference concentration range in the concentration determination step.

[0023] According to this method, when judging that the concentration of the sublimation substance in the liquid film of the pre-treatment liquid is lower than the lower limit of the reference concentration range in the concentration determination process, the solvent is promoted to evaporate from the liquid film of the pre-treatment liquid. If the solvent is promoted to evaporate from the liquid film of the pre-treatment liquid, the concentration of the sublimation substance in the liquid film of the pre-treatment liquid is increased. Therefore, the concentration of the sublimation substance in the liquid film of the pre-treatment liquid can be adjusted to within the reference concentration range. Therefore, even if judging that the concentration of the sublimation substance in the liquid film of the pre-treatment liquid is lower than the lower limit of the reference concentration range in the concentration determination process, the substrate having reduced the rate of failure of the pattern can be obtained.

[0024] In one embodiment of the present invention, the solvent evaporation promotion step includes a step of removing the vapor of the solvent from the gas atmosphere in contact with the liquid film by supplying an inert gas to the gas atmosphere in contact with the liquid film.

[0025] According to this method, the inert gas is supplied to remove the solvent vapor from the gas atmosphere in contact with the liquid film of the pre-drying treatment liquid on the upper surface of the substrate, thereby promoting the evaporation of the solvent from the liquid film of the pre-drying treatment liquid.

[0026] In one embodiment of the present invention, the substrate processing method further includes: a substrate rotation step, which is to rotate the upper surface of the substrate around a rotation axis along a vertical direction in the precipitation step; and a thin film step, which is to thin the liquid film by increasing the rotation speed of the substrate before the solid of the sublimable substance is precipitated during the execution of the precipitation step when it is determined in the concentration determination step that the concentration of the sublimable substance in the liquid film is higher than the upper limit value of the reference concentration range.

[0027] When the concentration of the sublimable substance in the liquid film of the drying pretreatment liquid is higher than the upper limit of the reference concentration range, the thickness of the solid of the sublimable substance before sublimation is greater than the intended value. If the thickness of the liquid film of the drying pretreatment liquid on the substrate is reduced, the amount of the sublimable substance contained in the liquid film of the drying pretreatment liquid is reduced, and therefore, the thickness of the solid of the sublimable substance is also reduced.

[0028] Therefore, when the concentration of the sublimable substance in the liquid film of the drying pre-treatment liquid is higher than the upper limit of the reference concentration range, by increasing the rotation speed of the substrate, the centrifugal force is acted on the liquid film of the drying pre-treatment liquid on the upper surface of the substrate, thereby the thickness of the liquid film of the drying pre-treatment liquid can be reduced before the solid of the sublimable substance is precipitated. Accordingly, the solid of the sublimable substance of the intended thickness can be precipitated. Therefore, even if it is determined in the concentration determination process that the concentration of the sublimable substance in the liquid film of the drying pre-treatment liquid is higher than the upper limit of the reference concentration range, it is possible to obtain a substrate that has reduced the failure rate of the pattern.

[0029] In one embodiment of the present invention, the substrate processing method further includes a solvent evaporation suppression step, wherein when the concentration of the sublimable substance in the liquid film is determined to be higher than the upper limit value of the reference concentration range in the concentration determination step, the solvent evaporation suppression step suppresses the evaporation of the solvent from the liquid film during the execution of the precipitation step.

[0030] According to this method, when the concentration of the sublimable substance in the liquid film is determined to be higher than the upper limit of the reference concentration range in the concentration determination process, the evaporation of the liquid film of the pre-treatment liquid of the solvent is suppressed. If the evaporation of the liquid film of the pre-treatment liquid of the solvent is suppressed, the ratio of the sublimable substance in the material evaporated from the liquid film increases. Accordingly, the concentration of the sublimable substance in the liquid film of the pre-treatment liquid of the drying process is reduced. Therefore, the concentration of the sublimable substance in the liquid film of the pre-treatment liquid of the drying process can be adjusted to within the reference concentration range.

[0031] Therefore, even if the concentration of the sublimable substance in the liquid film of the drying pre-treatment liquid is determined to be higher than the upper limit of the reference concentration range in the concentration determination step, a substrate having a reduced pattern failure rate can be obtained.

[0032] In one embodiment of the present invention, the solvent evaporation suppression step includes a step of suppressing evaporation of the solvent from the liquid film by supplying vapor or mist of the solvent to a gas atmosphere in contact with the liquid film.

[0033] According to this method, the amount of solvent present in the gas atmosphere in contact with the liquid film of the drying pretreatment liquid on the upper surface of the substrate is increased by supplying the vapor or mist of the solvent to the gas atmosphere in contact with the liquid film of the drying pretreatment liquid, thereby suppressing the evaporation of the solvent from the liquid film of the drying pretreatment liquid.

[0034] In one embodiment of the present invention, the substrate processing method further includes a first abnormality notification step, wherein the first abnormality notification step is to notify an abnormality when it is determined in the concentration determination step that the concentration of the sublimable substance in the liquid film is not within the reference concentration range. Therefore, it is possible to determine whether to continue the substrate processing at an appropriate time based on the notification of the abnormality.

[0035] In one embodiment of the present invention, the substrate processing method further includes: a film thickness measuring step, which is to measure the thickness of the liquid film before the solid of the sublimable substance is about to precipitate out through the evaporation of the solvent in the precipitation step; and a thickness determination step, which is to determine whether the thickness of the liquid film measured in the film thickness measuring step is within the reference thickness range of the solid of the sublimable substance.

[0036] According to the method, determine whether the thickness of the liquid film before the solid of the sublimable substance is about to separate out, that is, the thickness of the liquid film when the concentration of the sublimable substance reaches the saturation concentration of the sublimable substance is within the reference thickness range of the solid of the sublimable substance. Accordingly, it is possible to determine whether the thickness of the solid of the sublimable substance formed on the upper surface of the substrate is appropriate.

[0037] When the thickness of the solid of the sublimable substance formed on the upper surface of the substrate is appropriate, after the precipitation process is completed, a solid of the sublimable substance of appropriate thickness is formed. Therefore, a substrate having reduced the failure rate of the pattern can be obtained.

[0038] On the other hand, when the thickness of the solid of the sublimable substance formed on the upper surface of the substrate is inappropriate, the increase in the failure rate of the pattern can be suppressed by interrupting the substrate processing.

[0039] In one embodiment of the present invention, the substrate processing method further includes a second abnormality notification step, wherein the second abnormality notification step is to notify an abnormality when it is determined in the thickness determination step that the thickness of the liquid film measured in the film thickness measurement step is not within the reference thickness range. Therefore, it is possible to determine whether to continue the substrate processing at an appropriate time based on the notification of the abnormality.

[0040] In one embodiment of the present invention, the substrate processing method further comprises: a first precipitation step, which is to evaporate the solvent from the drying pre-treatment liquid on the upper surface of the substrate, so that the solid of the sublimable substance is precipitated in the drying pre-treatment liquid on the upper surface of the substrate; a first dissolution step, which is to dissolve at least a part of the solid of the sublimable substance in the first precipitation step in the drying pre-treatment liquid on the upper surface of the substrate; and a final precipitation step, which is to evaporate the drying pre-treatment liquid formed by dissolving the solid of the sublimable substance in the first dissolution step, so that the solid of the sublimable substance is precipitated on the upper surface of the substrate. Furthermore, the precipitation step is the first precipitation step, and the sublimation step is performed after the final precipitation step is completed. In addition, the first dissolution step is performed when the thickness of the liquid film is determined to be within the reference thickness range in the thickness determination step.

[0041] When the solid of the sublimable substance begins to precipitate in the first precipitation process, the drying pre-treatment liquid remains on the upper surface of the substrate. In the first dissolution process, at least a portion of the solid of the sublimable substance is dissolved in the drying pre-treatment liquid. Thereafter, in the final precipitation process, the solvent is evaporated from the drying pre-treatment liquid again. Accordingly, the content of the solvent is reduced, and the solid of the sublimable substance is precipitated on the upper surface of the substrate.

[0042] Before the solid of the sublimable substance is first precipitated, the pre-drying treatment liquid exists not only between the patterns but also above the patterns. In substrates such as semiconductor wafers and FPD substrates, the spacing between the patterns is narrow. When the spacing between the patterns is narrow, the properties of the pre-drying treatment liquid existing between the patterns are different from those of the main body of the pre-drying treatment liquid, in other words, the pre-drying treatment liquid located in the range from the surface of the pre-drying treatment liquid on the upper surface of the substrate to the upper surface of the pattern. The difference in the properties of the two becomes significant as the spacing between the patterns becomes narrower.

[0043] If the interval between the patterns is narrow, the following situation may occur: when the solid of the sublimable substance is precipitated for the first time, the solid of the sublimable substance is precipitated only in the main body of the pre-drying treatment liquid, and the incomplete precipitation area between the patterns where the solid of the sublimable substance does not exist or hardly exists is formed in the upper surface of the substrate. In this case, the surface tension of the pre-drying treatment liquid between the patterns is applied to the side of the pattern, so when the solid of the sublimable substance sublimates, the pattern in the incomplete precipitation area may be damaged. This becomes the reason for the increase in the damage rate (deterioration) of the pattern.

[0044] In contrast, if after making the solid dissolution of the sublimable substance of separation in the dry pre-treatment liquid, the solid of the sublimable substance is separated out again, then also in the narrower space such as the space between the pattern, the solid nucleus of the sublimable substance is formed.Therefore, as long as after making the solid dissolution of the sublimable substance of separation in the dry pre-treatment liquid in the 1st dissolving process, in the final separation process, the solid of the sublimable substance is separated out again, then even when the narrower situation at the interval of the pattern, the generation of the incomplete separation zone can be prevented, or its area can be reduced.

[0045] In addition, according to this method, the first dissolving process starts when the thickness of the liquid film of the dry pre-treatment liquid is determined to be within the reference thickness range in the thickness determination process. In other words, the first dissolving process starts with the solid of the sublimation material having formed an appropriate thickness as an opportunity. Therefore, only when the solid of the sublimation material having formed an appropriate thickness is used, the first dissolving process, the final precipitation process, and the sublimation process are performed. After the sublimation process ends, a substrate with a reduced failure rate of the pattern can be obtained.

[0046] When a solid of the sublimable substance is not formed to an appropriate thickness, the steps after the first precipitation step (the first dissolution step, the final precipitation step, and the sublimation step) may not be performed, and the substrate processing may be interrupted early.

[0047] In one embodiment of the present invention, the substrate processing method further comprises: a first precipitation step, which is to evaporate the solvent from the drying pre-treatment liquid on the upper surface of the substrate, so that the solid of the sublimable substance is precipitated in the drying pre-treatment liquid on the upper surface of the substrate; a first dissolution step, which is to dissolve at least a part of the solid of the sublimable substance in the drying pre-treatment liquid on the upper surface of the substrate; and a final precipitation step, which is to evaporate the drying pre-treatment liquid formed by dissolving the solid of the sublimable substance from the solvent, so that the solid of the sublimable substance is precipitated on the upper surface of the substrate. Furthermore, the precipitation step comprises at least one of the first precipitation step and the final precipitation step, and the sublimation step is performed after the final precipitation step.

[0048] According to this method, after the precipitated sublimation substance solid is dissolved in the drying pre-treatment liquid, the sublimation substance solid is precipitated again. Therefore, even when the interval of the pattern is narrow, the generation of the incomplete precipitation area can be prevented or its area can be reduced. Accordingly, the pattern failure can be reduced and the failure rate of the pattern can be reduced.

[0049] In addition, according to the method, in at least any operation in the 1st precipitation operation and the final precipitation operation, before the solid of sublimable substance is precipitated, that is, before the concentration of sublimable substance reaches the saturation concentration of sublimable substance, it is determined whether the concentration of sublimable substance in the liquid film is within the reference concentration range. When the concentration of sublimable substance in the judgment liquid film is the situation within the reference concentration range, the solid of sublimable substance of suitable thickness is formed. And, owing to make the solid of sublimable substance sublimate after the final precipitation operation finishes, the substrate having reduced the failure rate of pattern can be obtained.

[0050] On the other hand, when the concentration of the sublimable substance in the judgment liquid film is not within the scope of the reference concentration, if the substrate processing is interrupted, the situation of the solid sublimation of the sublimable substance of inappropriate thickness can be prevented before it happens. Accordingly, the rise of the failure rate of the pattern can be suppressed.

[0051] The failure rate of pattern depends on the thickness of the solid of the sublimation substance on the upper surface of substrate that is finally formed, and therefore, the concentration determination operation is preferably performed in the final precipitation operation.But the amount of the solvent evaporated in the 1st dissolving operation and the final precipitation operation can be predicted.Therefore, even when the concentration determination operation is performed in the 1st precipitation operation, it is also possible to determine whether the thickness of the solid of the sublimation substance on the upper surface of substrate is appropriate according to the concentration of the sublimation substance in the liquid film in the 1st precipitation operation.

[0052] Another embodiment of the present invention provides a substrate processing method, which includes: a drying pre-treatment liquid supplying step, which is to supply a solution formed by dissolving a sublimable substance in a solvent, that is, a drying pre-treatment liquid, to the upper surface of a substrate formed with a pattern, and form a liquid film of the drying pre-treatment liquid on the upper surface of the substrate; a precipitation step, which is to evaporate the solvent from the liquid film, thereby precipitating a solid of the sublimable substance on the upper surface of the substrate; a flatness measuring step, which is to measure the height position of the solid of the sublimable substance at multiple locations on the upper surface of the substrate after the solid of the sublimable substance is precipitated by evaporation of the solvent in the precipitation step, thereby measuring the flatness of the surface of the solid of the sublimable substance; a flatness judging step, which is to judge whether the flatness measured in the flatness judging step is within a reference flatness range; and a sublimation step, which is to sublime the solid of the sublimable substance when it is judged in the flatness judging step that the flatness is within the reference flatness range.

[0053] According to this method, the solution formed by dissolving the sublimable substance in the solvent is supplied to the upper surface of the substrate. Accordingly, the liquid film of the dry pre-treatment liquid is formed on the upper surface of the substrate. Thereafter, the solvent is evaporated from the liquid film of the dry pre-treatment liquid. The concentration of the sublimable substance in the liquid film of the dry pre-treatment liquid rises along with the evaporation of the solvent. If the concentration of the sublimable substance reaches the saturation concentration of the sublimable substance, the solid of the sublimable substance is separated out in the liquid film of the dry pre-treatment liquid.

[0054] When there is a part of the solid of the sublimable substance that is too thin or too thick, there is a risk that the failure rate of the pattern in the part will increase. Therefore, the flatness of the surface of the solid of the sublimable substance precipitated on the upper surface of the substrate is measured, and it is determined whether the measured flatness is within the reference flatness range. Accordingly, it is possible to check whether the solid of the sublimable substance with uniform thickness is formed in the entire area of ​​the upper surface of the substrate.

[0055] When the flatness of the solid of the sublimable substance is determined to be within the reference flatness range, the solid of the sublimable substance is sublimated, thereby obtaining a substrate with a reduced pattern failure rate. On the other hand, when the flatness of the solid of the sublimable substance is determined not to be within the reference flatness range, the substrate processing can be interrupted to suppress the generation of a substrate with an increased pattern failure rate.

[0056] In another embodiment of the present invention, the substrate processing method further includes a solid removal process, wherein when it is determined in the flatness measuring process that the flatness is not within the reference flatness range, the solid of the sublimable substance is removed from the upper surface of the substrate by supplying a removal liquid to the upper surface of the substrate.

[0057] According to this method, when the flatness of the solid of the sublimable substance is not within the range of the reference flatness, the solid of the sublimable substance is removed from the upper surface of the substrate by removing liquid. Therefore, when there is a part of the solid of the sublimable substance with a thin or thick part, the pattern can also be suppressed from being ruined. In addition, since the solid of the sublimable substance on the upper surface of the substrate is removed, the substrate can be reused.

[0058] Another embodiment of the present invention provides a substrate processing device, which includes: a drying pre-treatment liquid supply unit, which supplies a solution formed by dissolving a sublimable substance in a solvent, that is, a drying pre-treatment liquid, to the upper surface of the substrate formed with a pattern in a manner of forming a liquid film on the upper surface of the substrate; a solvent evaporation unit, which evaporates the solvent from the liquid film in a manner of precipitating a solid of the sublimable substance; a film thickness measurement unit, which measures the thickness of the liquid film; a sublimation unit, which sublimates the solid of the sublimable substance formed on the substrate; and a controller, which determines whether the concentration of the sublimable substance in the liquid film is within a reference concentration range. According to this configuration, the same effect as the above-mentioned substrate processing method is achieved.

[0059] The above-mentioned object and other objects, features and effects of the present invention will become clear through the following description of the embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1A This is a schematic diagram of a substrate processing apparatus according to an embodiment of the present invention as viewed from above.

[0061] Figure 1B It is a schematic diagram of the substrate processing apparatus viewed from the side.

[0062] Figure 2 It is a schematic diagram of the interior of a processing unit included in the substrate processing apparatus when viewed horizontally.

[0063] Figure 3 It is a schematic diagram of horizontally viewing the film thickness measuring unit, the spin chuck, and the shielding member included in the processing unit.

[0064] Figure 4 It is a schematic diagram of the film thickness measuring unit and the spin chuck viewed from above.

[0065] Figure 5 It is a cross-sectional view showing the interior of a housing that accommodates a light-emitting element included in the film-thickness measuring unit.

[0066] Figure 6 It is along Figure 5 A cross-sectional view taken along line VI-VI is shown.

[0067] Figure 7 It is a schematic diagram showing a drying pre-processing liquid supply device provided in the substrate processing apparatus.

[0068] Figure 8 It is a block diagram showing the hardware of a controller included in the substrate processing apparatus.

[0069] Fig. 9 This is a flowchart for explaining an example of substrate processing performed by the substrate processing apparatus.

[0070] Fig. 10A This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0071] Fig. 10B This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0072] Fig. 10C This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0073] Fig. 10D This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0074] Fig. 10E This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0075] Fig.10F This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0076] Fig.11 This is the equilibrium diagram of camphor and IPA.

[0077] Fig. 12A This is a schematic diagram showing the state of a substrate when a solution of camphor and methanol is used.

[0078] Fig. 12B This is a schematic diagram showing the state of a substrate when a solution of camphor and methanol is used.

[0079] Fig. 12C This is a schematic diagram showing the state of a substrate when a solution of camphor and methanol is used.

[0080] Fig.12D This is a schematic diagram showing the state of a substrate when a solution of camphor and methanol is used.

[0081] Fig.13 It is a graph showing the deterioration rate of a pattern.

[0082] Fig.14This is a graph showing the change over time in the thickness of the liquid film of the pre-drying treatment liquid on the upper surface of the substrate until the solid of the sublimable substance is precipitated from the pre-drying treatment liquid.

[0083] Fig.15 This is a flowchart showing the flow of the first example of the film thickness monitoring process.

[0084] Fig.16 This is a schematic diagram for explaining the abnormality processing step in the first example of the above-mentioned film thickness monitoring step.

[0085] Fig.17 It is a flowchart showing the flow of the second example of the above-mentioned film thickness monitoring process.

[0086] Fig.18 This is a schematic diagram for explaining the solvent evaporation suppression step in the second example of the film thickness monitoring step.

[0087] Fig.19 This is a schematic diagram for explaining the solvent evaporation promotion step in the second example of the film thickness monitoring step.

[0088] Fig. 20 It is a flowchart showing the flow of the third example of the above-mentioned film thickness monitoring process.

[0089] Fig.21A This is a schematic diagram for explaining the thinning step in the third example of the film thickness monitoring step.

[0090] Fig.21B This is a schematic diagram for explaining the thinning step in the third example of the film thickness monitoring step.

[0091] Fig. 22 It is a flowchart showing the flow of the fourth example of the above-mentioned film thickness monitoring process.

[0092] Fig.23 This is a flowchart for explaining another example of substrate processing performed by the above-mentioned substrate processing apparatus.

[0093] Fig.24 It is a flowchart showing the flow of the fifth example of the above-mentioned film thickness monitoring step.

[0094] Fig.25A It is a schematic diagram for explaining the flatness measuring step in the above-mentioned substrate processing.

[0095] Fig.25B It is a schematic diagram for explaining the solid removal process in the above-mentioned substrate processing.

[0096] Fig.25C It is a schematic diagram for explaining the solid removal process in the above-mentioned substrate processing. DETAILED DESCRIPTION

[0097] In the following description, unless otherwise specified, the pressure in the substrate processing apparatus 1 is maintained at the pressure in the clean room where the substrate processing apparatus 1 is installed (for example, 1 atmosphere or a value close thereto).

[0098] Figure 1A It is a schematic diagram of the substrate processing apparatus 1 according to one embodiment of the present invention as viewed from above. Figure 1B It is a schematic diagram of the substrate processing apparatus 1 viewed from the side.

[0099] like Figure 1A As shown, the substrate processing device 1 is a monolithic device that processes circular plate-shaped substrates W such as semiconductor wafers one by one. The substrate processing device 1 includes: a load port LP that holds a carrier CA that accommodates the substrates W; a plurality of processing units 2 that use processing fluids such as processing liquids and processing gases to process the substrates W transported from the carrier CA on the load port LP; a transport robot that transports the substrates W between the carrier CA on the load port LP and the processing units 2; and a controller 3 that controls the substrate processing device 1.

[0100] The transport robot includes: an indexing robot IR, which carries substrates W in and out of a carrier CA on a load port LP; and a central robot CR, which carries substrates W in and out of a plurality of processing units 2. The indexing robot IR carries substrates W between the load port LP and the central robot CR, and the central robot CR carries substrates W between the indexing robot IR and the processing unit 2. The central robot CR includes a hand H1 for supporting the substrate W, and the indexing robot IR includes a hand H2 for supporting the substrate W.

[0101] The plurality of processing units 2 form a plurality of towers TW arranged around the central robot CR in a plan view. Figure 1A The example in which four towers TW are formed is shown. The central robot CR can enter any tower TW. Figure 1B As shown, each tower TW includes a plurality of (for example, three) processing units 2 stacked up and down.

[0102] Figure 2 It is a schematic diagram of the interior of the processing unit 2 included in the substrate processing apparatus 1 when viewed horizontally.

[0103] The processing unit 2 is a wet processing unit 2w that supplies a processing liquid to the substrate W. The processing unit 2 includes: a box-shaped chamber 4 having an internal space; a spin chuck 10 that holds a substrate W horizontally in the chamber 4 and rotates the substrate W around a vertical rotation axis A1 passing through the center of the upper surface of the substrate W; and a cylindrical processing cup 21 that surrounds the spin chuck 10 around the rotation axis A1.

[0104] The chamber 4 includes: a box-shaped partition wall 5, which is provided with a loading and unloading port 5b for the substrate W to pass through; and a shutter 7, which opens and closes the loading and unloading port 5b. The FFU (fan filter unit) 6 is arranged above the air supply port 5a arranged on the upper part of the partition wall 5. The FFU 6 always supplies clean air (air filtered by the filter) from the air supply port 5a to the chamber 4. The gas in the chamber 4 is discharged from the chamber 4 via the exhaust duct 8 connected to the bottom of the processing cup 21. Accordingly, a downward flow of clean air is always formed in the chamber 4. The flow rate of the exhaust gas discharged by the exhaust duct 8 changes according to the opening of the exhaust valve 9 arranged in the exhaust duct 8.

[0105] The spin chuck 10 includes: a disk-shaped spin base 12 held in a horizontal position; a plurality of chuck pins 11 holding the substrate W in a horizontal position above the spin base 12; a rotation shaft 13 extending downward from the center of the spin base 12; and a rotation motor 14 that rotates the spin base 12 and the plurality of chuck pins 11 by rotating the rotation shaft 13. The spin chuck 10 is not limited to a clamping chuck in which the plurality of chuck pins 11 are in contact with the outer peripheral surface of the substrate W, but may be a vacuum chuck in which the substrate W is held horizontally by adsorbing the non-device forming surface, that is, the back surface (lower surface) of the substrate W to the upper surface 12u of the spin base 12.

[0106] The processing cup 21 includes: a plurality of sheaths 24 that receive the processing liquid discharged from the substrate W to the outside; a plurality of cups 23 that receive the processing liquid guided downward through the plurality of sheaths 24; and a cylindrical outer wall member 22 that surrounds the plurality of sheaths 24 and the plurality of cups 23. Figure 2 An example is shown in which four sheaths 24 and three cups 23 are provided, and the outermost cup 23 is integrated with the third sheath 24 from the top.

[0107] The sheath 24 includes: a cylindrical portion 25, which surrounds the rotating chuck 10; and an annular top portion 26, which extends obliquely upward from the upper end of the cylindrical portion 25 toward the rotation axis A1. A plurality of top portions 26 overlap each other, and a plurality of cylindrical portions 25 are arranged in a concentric circle. The annular upper end of the top portion 26 corresponds to the upper end 24u of the sheath 24 surrounding the substrate W and the rotating base 12 in a top view. A plurality of cups 23 are respectively arranged below the plurality of cylindrical portions 25. The cups 23 form an annular liquid receiving groove for receiving the processing liquid guided downward by the sheath 24.

[0108] The processing unit 2 includes a sheath lifting unit 27 for lifting each of the plurality of sheaths 24. The sheath lifting unit 27 positions the sheath 24 at any position from an upper position to a lower position. The sheath lifting unit 27 is also called a sheath lifter. Figure 2The state in which two covers 24 are arranged in the upper position and the remaining two covers 24 are arranged in the lower position is shown. The upper position is that the upper end 24u of the cover 24 is arranged at a position higher than the holding position where the substrate W held by the spin chuck 10 is arranged. The lower position is that the upper end 24u of the cover 24 is arranged at a position lower than the holding position.

[0109] When the processing liquid is supplied to the rotating substrate W, at least one of the sheaths 24 is arranged in the upper position. In this state, when the processing liquid is supplied to the substrate W, the processing liquid supplied to the substrate W is thrown around the substrate W. The thrown processing liquid collides with the inner surface of the sheath 24 horizontally opposite to the substrate W, and is guided to the cup 23 corresponding to the sheath 24. Accordingly, the processing liquid discharged from the substrate W is collected in the processing cup 21.

[0110] The processing unit 2 includes a plurality of nozzles for spraying a processing liquid onto the substrate W held by the spin chuck 10. The plurality of nozzles include: a chemical liquid nozzle 31 for spraying a chemical liquid onto the upper surface of the substrate W; a rinse liquid nozzle 35 for spraying a rinse liquid onto the upper surface of the substrate W; a drying pre-processing liquid nozzle 39 for spraying a drying pre-processing liquid onto the upper surface of the substrate W; and a replacement liquid nozzle 43 for spraying a replacement liquid onto the upper surface of the substrate W.

[0111] The chemical liquid nozzle 31 may be a scanning nozzle that can move horizontally in the chamber 4 or a fixed nozzle that is fixed to the partition wall 5 of the chamber 4. The same is true for the rinse liquid nozzle 35, the pre-drying treatment liquid nozzle 39, and the replacement liquid nozzle 43. Figure 2 The example in which the chemical liquid nozzle 31 , the rinse liquid nozzle 35 , the pre-drying treatment liquid nozzle 39 , and the replacement liquid nozzle 43 are scanning nozzles and four nozzle moving units corresponding to the four nozzles are provided is shown.

[0112] The liquid medicine nozzle 31 is connected to a liquid medicine pipe 32 that guides the liquid medicine to the liquid medicine nozzle 31. When a liquid medicine valve 33 installed in the liquid medicine pipe 32 is opened, the liquid medicine is continuously ejected downward from the ejection port of the liquid medicine nozzle 31. The liquid medicine ejected from the liquid medicine nozzle 31 may be a liquid containing at least one of sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid, phosphoric acid, acetic acid, ammonia water, hydrogen peroxide water, an organic acid (e.g., citric acid, oxalic acid, etc.), an organic base (e.g., TMAH: tetramethylammonium hydroxide, etc.), a surfactant, and a preservative, or may be other liquids.

[0113] Although not shown in the figure, the liquid medicine valve 33 includes: a valve body, which is provided with an annular valve seat for the liquid medicine to pass through; a valve body, which is movable relative to the valve seat; and a driver, which moves the valve body between a closed position where the valve body contacts the valve seat and an open position where the valve body is away from the valve seat. The same is true for other valves. The driver may be a pneumatic driver or an electric driver, or a driver other than these. The controller 3 controls the driver to open and close the liquid medicine valve 33.

[0114] The chemical liquid nozzle 31 is connected to a nozzle moving unit 34 that moves the chemical liquid nozzle 31 in at least one of a vertical direction and a horizontal direction. The nozzle moving unit 34 moves the chemical liquid nozzle 31 horizontally between a processing position where the chemical liquid ejected from the chemical liquid nozzle 31 is supplied to the upper surface of the substrate W and a standby position where the chemical liquid nozzle 31 is located around the processing cup 21 in a plan view.

[0115] The rinse liquid nozzle 35 is connected to a rinse liquid pipe 36 that guides the rinse liquid to the rinse liquid nozzle 35. When the rinse liquid valve 37 installed in the rinse liquid pipe 36 is opened, the rinse liquid is continuously ejected downward from the ejection port of the rinse liquid nozzle 35. The rinse liquid ejected from the rinse liquid nozzle 35 is, for example, pure water (deionized water: DIW (Deionized Water)). The rinse liquid may also be any one of carbonated water, electrolytic ion water, hydrogen water, ozone water, and hydrochloric acid water of a diluted concentration (for example, about 10ppm to 100ppm).

[0116] The rinse liquid nozzle 35 is connected to a nozzle moving unit 38 that moves the rinse liquid nozzle 35 in at least one of a vertical direction and a horizontal direction. The nozzle moving unit 38 moves the rinse liquid nozzle 35 horizontally between a processing position where the rinse liquid sprayed from the rinse liquid nozzle 35 is supplied to the upper surface of the substrate W and a standby position where the rinse liquid nozzle 35 is located around the processing cup 21 in a plan view.

[0117] The pre-drying liquid nozzle 39 is connected to a pre-drying liquid piping 40 that guides the treatment liquid to the pre-drying liquid nozzle 39. When a pre-drying liquid valve 41 installed in the pre-drying liquid piping 40 is opened, the pre-drying liquid is continuously ejected downward from the ejection port of the pre-drying liquid nozzle 39. Similarly, the replacement liquid nozzle 43 is connected to a replacement liquid piping 44 that guides the replacement liquid to the replacement liquid nozzle 43. When a replacement liquid valve 45 installed in the replacement liquid piping 44 is opened, the replacement liquid is continuously ejected downward from the ejection port of the replacement liquid nozzle 43.

[0118] The pre-drying treatment liquid is a solution containing a sublimable substance as a solute and a solvent for dissolving the sublimable substance. The sublimable substance can be a substance that changes from a solid to a gas without passing through a liquid at normal temperature (synonymous with room temperature) or normal pressure (pressure in the substrate processing device 1, such as 1 atmosphere or a value near it).

[0119] The freezing point of the drying pretreatment liquid (freezing point at 1 atmosphere, the same below) is lower than room temperature (for example, 23°C or a value in the vicinity thereof). The substrate processing apparatus 1 is arranged in a clean room maintained at room temperature. Therefore, even if the drying pretreatment liquid is not heated, the drying pretreatment liquid can be maintained as a liquid. The freezing point of the sublimable substance is higher than the freezing point of the drying pretreatment liquid. The freezing point of the sublimable substance is higher than room temperature. At room temperature, the sublimable substance is solid. The freezing point of the sublimable substance may also be higher than the boiling point of the solvent. The vapor pressure of the solvent is higher than the vapor pressure of the sublimable substance.

[0120] Sublimable substances may be alcohols such as 2-methyl-2-propanol (also known as tert-Butyl alcohol, t-Butyl alcohol), cyclohexanol, fluorinated hydrocarbon compounds, 1,3,5-trifluoromethane, Any of alkane (another name: trioxymethylene), camphor (another name: camphor (camphre), camphor (campher)), naphthalene and iodine may be used, or substances other than these may be used.

[0121] The solvent may be, for example, at least one selected from the group consisting of pure water, IPA, methanol, HFE (hydrofluoroether), acetone, PGMEA (propylene glycol monomethyl ether acetate), PGEE (propylene glycol monoethyl ether, 1-ethoxy-2-propanol), and ethylene glycol.

[0122] Hereinafter, an example in which the sublimable substance is camphor and the solvent is IPA or methanol will be described.

[0123] The freezing point of camphor is 175℃~177℃. Regardless of whether the solvent is IPA or methanol, the freezing point of camphor is higher than the boiling point of the solvent. The vapor pressure of IPA is higher than that of camphor. Similarly, the vapor pressure of methanol is higher than that of camphor. Therefore, IPA and methanol are easier to evaporate than camphor. The vapor pressure of IPA is higher than that of water, and the surface tension is lower than that of water. Similarly, the vapor pressure of methanol is higher than that of water, and the surface tension is lower than that of water. The molecular weights of IPA and methanol are both greater than that of water. The molecular weight of methanol is smaller than that of IPA.

[0124] As described below, the replacement liquid is supplied to the upper surface of the substrate W covered by the liquid film of the rinsing liquid, and the pre-drying treatment liquid is supplied to the upper surface of the substrate W covered by the liquid film of the replacement liquid. As long as it is compatible with both the rinsing liquid and the pre-drying treatment liquid, the replacement liquid can be any liquid. The replacement liquid is, for example, IPA (liquid). The replacement liquid can also be a mixed liquid of IPA and HFE, or a liquid other than them. The replacement liquid can be a liquid with the same name as the components of the pre-drying treatment liquid such as the solvent, or a liquid with a name different from any component of the pre-drying treatment liquid.

[0125] When the replacement liquid is supplied to the upper surface of the substrate W covered by the liquid film of the rinsing liquid, most of the rinsing liquid on the substrate W is washed away by the replacement liquid and discharged from the substrate W. The remaining trace amount of rinsing liquid dissolves in the replacement liquid and diffuses in the replacement liquid. The diffused rinsing liquid is discharged from the substrate W together with the replacement liquid. Therefore, the rinsing liquid on the substrate W can be effectively replaced with the replacement liquid. For the same reason, the replacement liquid on the substrate W can be effectively replaced with the drying pre-treatment liquid. Accordingly, the rinsing liquid contained in the drying pre-treatment liquid on the substrate W can be reduced.

[0126] The drying pre-processing liquid nozzle 39 is connected to a nozzle moving unit 42 that moves the drying pre-processing liquid nozzle 39 in at least one of a vertical direction and a horizontal direction. The nozzle moving unit 42 moves the drying pre-processing liquid nozzle 39 horizontally between a processing position where the drying pre-processing liquid ejected from the drying pre-processing liquid nozzle 39 is supplied to the upper surface of the substrate W and a standby position where the drying pre-processing liquid nozzle 39 is located around the processing cup 21 in a plan view.

[0127] Similarly, the replacement liquid nozzle 43 is connected to a nozzle moving unit 46 that moves the replacement liquid nozzle 43 in at least one of a vertical direction and a horizontal direction. The nozzle moving unit 46 moves the replacement liquid nozzle 43 horizontally between a processing position where the replacement liquid ejected from the replacement liquid nozzle 43 is supplied to the upper surface of the substrate W and a standby position where the replacement liquid nozzle 43 is located around the processing cup 21 in a plan view.

[0128] The processing unit 2 includes a blocking member 51 disposed above the spin chuck 10 . Figure 2 An example in which the blocking member 51 is a disk-shaped blocking plate is shown. The blocking member 51 includes a disk portion 52 horizontally arranged above the rotating chuck 10. The blocking member 51 is horizontally supported by a cylindrical support shaft 53 extending upward from the central portion of the disk portion 52. The center line of the disk portion 52 is arranged on the rotation axis A1 of the substrate W. The lower surface of the disk portion 52 is equivalent to the lower surface 51L of the blocking member 51. The lower surface 51L of the blocking member 51 is an opposite surface to the upper surface of the substrate W. The lower surface 51L of the blocking member 51 is parallel to the upper surface of the substrate W and has an outer diameter greater than the diameter of the substrate W.

[0129] The blocking member 51 is connected to a blocking member lifting unit 54 that vertically lifts the blocking member 51. The blocking member lifting unit 54 is also called a blocking member lifter. The blocking member lifting unit 54 places the blocking member 51 in the upper position ( Figure 2 The lower position is a close position where the lower surface 51L of the blocking member 51 approaches the upper surface of the substrate W until the scanning nozzles such as the liquid medicine nozzle 31 cannot enter the height between the substrate W and the blocking member 51. The upper position is a spaced position where the blocking member 51 is retreated until the scanning nozzles can enter the height between the blocking member 51 and the substrate W.

[0130] The plurality of nozzles include a central nozzle 55, which ejects a processing fluid such as a processing liquid or a processing gas downward through an upper central opening 61 formed in the central portion of the lower surface 51L of the blocking member 51. The central nozzle 55 extends up and down along the rotation axis A1. The central nozzle 55 is arranged in a through hole that penetrates the central portion of the blocking member 51 from top to bottom. The inner peripheral surface of the blocking member 51 surrounds the outer peripheral surface of the central nozzle 55 at intervals in the radial direction (in a direction orthogonal to the rotation axis A1). The central nozzle 55 is raised and lowered together with the blocking member 51. The ejection port of the central nozzle 55 that ejects the processing fluid is arranged above the upper central opening 61 of the blocking member 51.

[0131] The central nozzle 55 is connected to an upper gas pipe 56 that guides the inert gas to the central nozzle 55. The substrate processing apparatus 1 may also include an upper temperature regulator 59 that heats or cools the inert gas ejected from the central nozzle 55. When the upper gas valve 57 installed in the upper gas pipe 56 is opened, the inert gas is continuously ejected downward from the ejection port of the central nozzle 55 at a flow rate corresponding to the opening of the flow rate adjustment valve 58 that changes the flow rate of the inert gas. The inert gas ejected from the central nozzle 55 is nitrogen. The inert gas ejected from the central nozzle 55 may also be a gas other than nitrogen, such as helium or argon.

[0132] The inner circumferential surface of the blocking member 51 and the outer circumferential surface of the center nozzle 55 form a cylindrical upper gas flow path 62 extending up and down. The upper gas flow path 62 is connected to an upper gas pipe 63 that introduces an inert gas into the upper central opening 61 of the blocking member 51. The substrate processing apparatus 1 may also include an upper temperature regulator 66 that heats or cools the inert gas ejected from the upper central opening 61 of the blocking member 51. When the upper gas valve 64 installed in the upper gas pipe 63 is opened, the inert gas is continuously ejected downward from the upper central opening 61 of the blocking member 51 at a flow rate corresponding to the opening of the flow rate adjustment valve 65 that changes the flow rate of the inert gas. The inert gas ejected from the upper central opening 61 of the blocking member 51 is nitrogen. The inert gas ejected from the upper central opening 61 of the blocking member 51 may also be a gas other than nitrogen, such as helium or argon.

[0133] The plurality of nozzles include a lower surface nozzle 71 for spraying a processing liquid toward the center of the lower surface of the substrate W. The lower surface nozzle 71 includes: a nozzle disk portion, which is disposed between the upper surface 12u of the rotating base 12 and the lower surface of the substrate W; and a nozzle cylindrical portion, which extends downward from the nozzle disk portion. The spray port of the lower surface nozzle 71 forms an opening at the center of the upper surface of the nozzle disk portion. When the substrate W is held by the rotating chuck 10, the spray port of the lower surface nozzle 71 is opposite to the center of the lower surface of the substrate W.

[0134] The lower surface nozzle 71 is connected to a heating fluid piping 72 that guides warm water (pure water having a temperature higher than room temperature) as an example of a heating fluid to the lower surface nozzle 71. The pure water supplied to the lower surface nozzle 71 is heated by a heater 75 installed in the heating fluid piping 72. When a heating fluid valve 73 installed in the heating fluid piping 72 is opened, warm water is continuously ejected upward from the ejection port of the lower surface nozzle 71 at a flow rate corresponding to the opening degree of a flow rate adjustment valve 74 that changes the flow rate of warm water. In this way, warm water is supplied to the lower surface of the substrate W.

[0135] The lower surface nozzle 71 is further connected to a cooling fluid piping 76 that guides cold water (pure water having a temperature lower than room temperature) as an example of a cooling fluid to the lower surface nozzle 71. The pure water supplied to the lower surface nozzle 71 is cooled by a cooler 79 installed in the cooling fluid piping 76. When the cooling fluid valve 77 installed in the cooling fluid piping 76 is opened, the cold water is continuously ejected upward from the ejection port of the lower surface nozzle 71 at a flow rate corresponding to the opening degree of the flow rate adjustment valve 78 that changes the flow rate of the cold water. In this way, the cold water is supplied to the lower surface of the substrate W.

[0136] The outer peripheral surface of the lower surface nozzle 71 and the inner peripheral surface of the rotating base 12 form a cylindrical lower gas flow path 82 extending up and down. The lower gas flow path 82 includes a lower central opening 81 formed in the central portion of the upper surface 12u of the rotating base 12. The lower gas flow path 82 is connected to a lower gas pipe 83 for introducing an inert gas into the lower central opening 81 of the rotating base 12. The substrate processing apparatus 1 may also include a lower temperature regulator 86 for heating or cooling the inert gas ejected from the lower central opening 81 of the rotating base 12. When the lower gas valve 84 installed in the lower gas pipe 83 is opened, the inert gas is continuously ejected upward from the lower central opening 81 of the rotating base 12 at a flow rate corresponding to the opening degree of the flow rate adjustment valve 85 for changing the flow rate of the inert gas.

[0137] The inert gas ejected from the lower central opening 81 of the rotating base 12 is nitrogen. The inert gas ejected from the lower central opening 81 of the rotating base 12 may also be a gas other than nitrogen, such as helium or argon. When the substrate W is held by the rotating chuck 10, if nitrogen is ejected from the lower central opening 81 of the rotating base 12, the nitrogen flows radially in all directions between the lower surface of the substrate W and the upper surface 12u of the rotating base 12. As a result, the space between the substrate W and the rotating base 12 is filled with nitrogen.

[0138] Next, the film thickness measurement unit 91 will be described.

[0139] Figure 3 It is a schematic diagram of horizontally viewing the film thickness measurement unit 91 , the spin chuck 10 , and the shielding member 51 . Figure 4 It is a schematic diagram of the film thickness measurement unit 91 and the spin chuck 10 as viewed from above. Figure 5 It is a cross-sectional view showing the interior of a housing 93 that houses the light emitting element 92 . Figure 6 It means along Figure 5 A cross-sectional view taken along line VI-VI is shown.

[0140] like Figure 3 and Figure 4 As shown in FIG. 1 , the substrate processing apparatus 1 includes a film thickness measuring unit 91 for measuring the thickness (film thickness) of a liquid film present on the upper surface of the substrate W. The film thickness measuring unit 91 measures the film thickness by, for example, a spectroscopic interference method. The film thickness measuring unit 91 includes: a light emitting element 92 that emits light toward the upper surface of the substrate W held by the spin chuck 10; and a light receiving element 97 that receives the light of the light emitting element 92 reflected by the upper surface of the substrate W. The light emitting element 92 and the light receiving element 97 are arranged at positions that do not overlap with the spin chuck 10 and the shielding member 51 when viewed from above.

[0141] The light emitting element 92 is disposed in the housing 93. The light receiving element 97 is disposed in the housing 98. The light of the light emitting element 92 is emitted to the outside of the housing 93 from the opening of the housing 93 covered by the transparent plate 94. The light of the light emitting element 92 reflected by the upper surface of the substrate W passes through the opening of the housing 98 covered by the transparent plate 99 and enters the light receiving element 97 in the housing 98. Figure 3 and Figure 4 The black dots Pi in φ indicate the incident positions of the light from the light emitting element 92 on the upper surface of the substrate W. The thickness of the liquid film on the substrate W is calculated based on the light incident on the light receiving element 97 .

[0142] like Figure 5 and Figure 6 As shown, the film thickness measuring unit 91 includes: a holder 95 that holds the light emitting element 92 in a housing 93; and an electric motor 96 that moves the holder 95 relative to the housing 93. The holder 95 and the electric motor 96 are accommodated in the housing 93. The rotor and the stator of the electric motor 96 are accommodated in a motor housing 96a, and the rotating shaft 96b of the electric motor 96 protrudes from the end surface of the motor housing 96a toward the axial direction of the electric motor 96. The rotating shaft 96b is connected to the holder 95, and the motor housing 96a is connected to the housing 93.

[0143] The rotation angle of the electric motor 96 is controlled by the controller 3. When the electric motor 96 rotates the rotation shaft 96b, the holder 95 rotates together with the light emitting element 92 about the rotation axis A2 which is horizontal with respect to the housing 93. Figure 5 The white arrow in shows that the light emitting element 92 rotates around the rotation axis A2. Accordingly, the incident position of the light of the light emitting element 92 on the upper surface of the substrate W moves within the upper surface of the substrate W, and the incident angle of the light of the light emitting element 92 relative to the upper surface of the substrate W changes. Therefore, if the electric motor 96 is rotated, the light of the light emitting element 92 can be incident on multiple positions within the upper surface of the substrate W, and the film thickness can be measured at multiple positions within the upper surface of the substrate W.

[0144] If the incident position and the incident angle change, the path through which the reflected light of the light emitting element 92 reflected by the upper surface of the substrate W passes also changes. The light receiving element 97 may be movable in a manner that can receive the reflected light even if the path of the reflected light changes. For example, as with the light emitting element 92, an electric motor that moves the light receiving element 97 relative to the housing 98 may be provided. Alternatively, a plurality of light receiving elements 97 corresponding to one light emitting element 92 may be provided. In these cases, even if the incident position and the incident angle change, the reflected light is received by the light receiving element 97, and the thickness of the liquid film on the substrate W can be measured.

[0145] When measuring the thickness of the liquid film on the substrate W, the controller 3 may rotate the substrate W on the spin chuck 10 while positioning the incident position at a fixed distance in the horizontal direction from the rotation axis A1, or may move the incident position in the radial direction (horizontal direction orthogonal to the rotation axis A1) of the substrate W. In the latter case, the average value of a plurality of measured values ​​may be treated as the film thickness.

[0146] Next, the drying pre-treatment liquid supply device 101 will be described. Figure 7 1 is a schematic diagram showing a pre-drying treatment liquid supply device 101 included in the substrate treatment apparatus 1 .

[0147] The substrate processing apparatus 1 includes a drying pre-processing liquid supply device 101 for supplying the drying pre-processing liquid to the drying pre-processing liquid nozzle 39 via the drying pre-processing liquid pipe 40. The drying pre-processing liquid supply device 101 includes: a first tank 102A, which corresponds to a stock liquid tank storing a stock liquid of the drying pre-processing liquid; and a second tank 102B, which corresponds to a solvent tank storing a solvent of the drying pre-processing liquid.

[0148] The stock solution of the pre-drying treatment liquid contains a sublimable substance and a solvent. The concentration of the sublimable substance in the stock solution of the pre-drying treatment liquid is higher than that of the pre-drying treatment liquid supplied to the substrate W. The stock solution of the pre-drying treatment liquid is diluted by the solvent supplied from the second tank 102B and then supplied to the substrate W. When the sublimable substance is liquid at room temperature, the stock solution of the pre-drying treatment liquid may not contain a solvent.

[0149] The pre-drying treatment liquid supply device 101 includes: a first circulation pipe 103A that circulates the stock liquid in the first tank 102A; a first pump 104A that sends the stock liquid in the first tank 102A to the first circulation pipe 103A; and a first individual pipe 105A that guides the stock liquid in the first circulation pipe 103A to the pre-drying treatment liquid pipe 40. The pre-drying treatment liquid supply device 101 further includes: a first opening and closing valve 106A that opens and closes the inside of the first individual pipe 105A; and a first flow regulating valve 107A that changes the flow rate of the pre-drying treatment liquid supplied from the first individual pipe 105A to the pre-drying treatment liquid pipe 40.

[0150] Similarly, the drying pre-treatment liquid supply device 101 includes: a second circulation pipe 103B that circulates the solvent in the second tank 102B; a second pump 104B that sends the solvent in the second tank 102B to the second circulation pipe 103B; and a second individual pipe 105B that guides the solvent in the second circulation pipe 103B to the drying pre-treatment liquid pipe 40. The drying pre-treatment liquid supply device 101 further includes: a second on-off valve 106B that opens and closes the inside of the second individual pipe 105B; and a second flow rate regulating valve 107B that changes the flow rate of the drying pre-treatment liquid supplied from the second individual pipe 105B to the drying pre-treatment liquid pipe 40.

[0151] The first individual pipe 105A and the second individual pipe 105B are connected to the drying pre-treatment liquid pipe 40 via a mixing valve 108 for generating the drying pre-treatment liquid by mixing the stock solution of the drying pre-treatment liquid with the solvent. The drying pre-treatment liquid pipe 40 is provided with not only the drying pre-treatment liquid valve 41 but also an in-pipe mixer 109. The in-pipe mixer 109 further mixes the drying pre-treatment liquid generated by the mixing valve 108. Thus, the drying pre-treatment liquid formed by uniformly mixing the sublimable substance and the solvent is supplied to the drying pre-treatment liquid nozzle 39.

[0152] The stock solution of the pre-drying treatment liquid supplied from the first tank 102A is supplied to the mixing valve 108 at a flow rate corresponding to the opening of the first flow regulating valve 107A. The solvent supplied from the second tank 102B is supplied to the mixing valve 108 at a flow rate corresponding to the opening of the second flow regulating valve 107B. Therefore, by changing the opening of the first flow regulating valve 107A and the second flow regulating valve 107B, the concentration of the sublimable substance in the pre-drying treatment liquid supplied to the pre-drying treatment liquid nozzle 39 can be changed.

[0153] The drying pretreatment liquid supply device 101 includes a concentration meter 110 for measuring the concentration of the drying pretreatment liquid supplied to the drying pretreatment liquid nozzle 39. The drying pretreatment liquid supply device 101 includes a measurement pipe 111 branched from the drying pretreatment liquid pipe 40. The concentration meter 110 is attached to the measurement pipe 111. Figure 7 The example in which the measuring pipe 111 is connected to the drying pretreatment liquid pipe 40 at a position downstream of the in-pipe mixer 109 is shown. Therefore, in this example, the concentration of the drying pretreatment liquid passing through both the mixing valve 108 and the in-pipe mixer 109 is measured by the concentration meter 110. The concentration meter 110 may be installed in the drying pretreatment liquid pipe 40 between the drying pretreatment liquid valve 41 and the in-pipe mixer 109 instead of being installed in the measuring pipe 111.

[0154] Figure 8 It is a block diagram showing the hardware of the controller 3.

[0155] The controller 3 is a computer including a computer body 3a and a peripheral device 3d connected to the computer body 3a. The computer body 3a includes a CPU 3b (central processing unit) for executing various commands and a main storage device 3c for storing information. The peripheral device 3d includes an auxiliary storage device 3e for storing information such as a program P, a reading device 3f for reading information from a removable medium RM, and a communication device 3g for communicating with other devices such as a host computer.

[0156] The controller 3 is connected to the input device 100A, the display device 100B and the alarm device 100C. The input device 100A is operated by an operator such as a user or a maintenance person in charge when inputting information into the substrate processing device 1. The information is displayed on the screen of the display device 100B. The input device 100A can be any one of a keyboard, a pointing device and a touch panel, or a device other than them. A touch panel display having both the input device 100A and the display device 100B can also be provided in the substrate processing device 1. The alarm device 100C uses one or more of light, sound, text and graphics to issue an alarm. When the input device 100A is a touch panel display, the input device 100A can also serve as the alarm device 100C.

[0157] The CPU 3b executes the program P stored in the auxiliary storage device 3e. The program P in the auxiliary storage device 3e may be a program preinstalled in the controller 3, or may be a program sent to the auxiliary storage device 3e from the removable medium RM via the reading device 3f, or may be a program sent to the auxiliary storage device 3e from an external device such as a computer via the communication device 3g.

[0158] The auxiliary storage device 3e and the removable medium RM are non-volatile memories that retain storage even when power is not supplied. The auxiliary storage device 3e is, for example, a magnetic storage device such as a hard disk drive. The removable medium RM is, for example, an optical disk such as a compact disk or a semiconductor memory such as a memory card. The removable medium RM is an example of a computer-readable recording medium on which the program P is recorded. The removable medium RM is a non-temporary tangible recording medium.

[0159] The auxiliary storage device 3e stores a plurality of processing plans. The processing plan is information that specifies the processing content, processing conditions, and processing sequence of the substrate W. The plurality of processing plans differ from each other in at least one of the processing content, processing conditions, and processing sequence of the substrate W. The controller 3 controls the substrate processing apparatus 1 in a manner of processing the substrate W according to the processing plan specified by the host computer. The following steps are executed by the controller 3 controlling the substrate processing apparatus 1. In other words, the controller 3 is programmed in a manner of executing the following steps.

[0160] Next, an example of substrate processing will be described.

[0161] The substrate W to be processed is, for example, a semiconductor wafer such as a silicon wafer. The surface of the substrate W corresponds to a device formation surface on which devices such as transistors and capacitors are formed. The substrate W may be a device formation surface, i.e., a surface of the substrate W, on which a pattern PA is formed (see Fig. 10A ) may be a substrate W having no pattern PA formed on the surface of the substrate W. In the latter case, the pattern PA may be formed by the chemical solution supplying step described later.

[0162] First, an example of substrate processing (first substrate processing example) in which the drying pre-processing liquid is a solution of camphor and IPA will be described.

[0163] Fig. 9 The following are process diagrams for explaining substrate processing performed by the substrate processing apparatus 1 . Figures 10A to 10F Schematic diagram showing the state of the substrate W when a solution of camphor and IPA is used. Fig.11 This is the equilibrium diagram of camphor and IPA. Fig.11 RT in the formula is room temperature. Figure 2 and Fig. 9 .about Figures 10A to 10F and Fig.11 , with appropriate reference.

[0164] When the substrate W is processed by the substrate processing apparatus 1, a loading process ( Fig. 9 In step S1), the substrate W is moved into the chamber 4.

[0165] Specifically, when the blocking member 51 is in the upper position, all the sheaths 24 are in the lower position, and all the scanning nozzles are in the standby position, the central robot CR (refer to FIG. 1 ) supports the substrate W with the hand H1 while allowing the hand H1 to enter the chamber 4. Then, the central robot CR places the substrate W on the hand H1 on the plurality of chuck pins 11 with the surface of the substrate W facing upward. Thereafter, the plurality of chuck pins 11 are pressed against the outer peripheral surface of the substrate W to secure the substrate W. Accordingly, the substrate W is held by rotating the chuck 10 (substrate holding process). The substrate holding process continues until the sublimation process ( Fig. 9 After the central robot CR places the substrate W on the spin chuck 10 , the hand H1 is withdrawn from the chamber 4 .

[0166] Next, the upper gas valve 64 and the lower gas valve 84 are opened, and nitrogen gas begins to be ejected from the upper central opening 61 of the blocking member 51 and the lower central opening 81 of the rotating base 12. Accordingly, the space between the substrate W and the blocking member 51 is filled with nitrogen gas. Similarly, the space between the substrate W and the rotating base 12 is filled with nitrogen gas. On the other hand, the sheath lifting unit 27 raises at least one sheath 24 from the lower position to the upper position. Thereafter, the rotary motor 14 is driven to start rotating the substrate W at a predetermined liquid supply speed (substrate rotation process). The substrate rotation process continues until the sublimation process ( Fig. 9 Until step S10) is completed.

[0167] Next, the drug solution supply process is performed ( Fig. 9 In step S2), the chemical liquid is supplied to the upper surface of the substrate W to form a liquid film of the chemical liquid covering the entire area of ​​the upper surface of the substrate W.

[0168] Specifically, when the blocking member 51 is in the upper position and at least one of the sheaths 24 is in the upper position, the nozzle moving unit 34 moves the liquid medicine nozzle 31 from the standby position to the processing position. Thereafter, the liquid medicine valve 33 is opened, and the liquid medicine nozzle 31 starts to spray the liquid medicine (liquid medicine supply process, liquid medicine spraying process). When a predetermined time has passed since the liquid medicine valve 33 was opened, the liquid medicine valve 33 is closed, and the spraying of the liquid medicine is stopped. Thereafter, the nozzle moving unit 34 moves the liquid medicine nozzle 31 to the standby position.

[0169] The chemical liquid ejected from the chemical liquid nozzle 31 collides with the upper surface of the substrate W rotating at a predetermined chemical liquid supply speed, and then flows outward along the upper surface of the substrate W due to centrifugal force. Therefore, the chemical liquid is supplied to the entire upper surface of the substrate W, forming a liquid film of the chemical liquid covering the entire upper surface of the substrate W. When the chemical liquid nozzle 31 ejects the chemical liquid, the nozzle moving unit 34 may move the contact position of the chemical liquid relative to the upper surface of the substrate W so that the contact position passes through the central part and the peripheral part, or may keep the contact position stationary at the central part.

[0170] Next, the rinsing process is performed ( Fig. 9 In step S3), pure water as an example of a rinsing liquid is supplied to the upper surface of the substrate W to rinse the chemical liquid on the substrate W.

[0171] Specifically, when the blocking member 51 is in the upper position and at least one sheath 24 is in the upper position, the nozzle moving unit 38 moves the rinse liquid nozzle 35 from the standby position to the processing position. Thereafter, the rinse liquid valve 37 is opened, and the rinse liquid nozzle 35 starts to spray the rinse liquid (rinsing liquid supply process, rinse liquid spraying process). Before starting to spray pure water, in order to replace the sheath 24 that receives the liquid discharged from the substrate W, the sheath lifting unit 27 may also vertically move at least one sheath 24. When a predetermined time has passed after the rinse liquid valve 37 is opened, the rinse liquid valve 37 is closed to stop spraying the rinse liquid. Thereafter, the nozzle moving unit 38 moves the rinse liquid nozzle 35 to the standby position.

[0172] After the pure water ejected from the rinse liquid nozzle 35 collides with the upper surface of the substrate W rotating at a predetermined rinse liquid supply speed, it flows outward along the upper surface of the substrate W due to centrifugal force. The chemical liquid on the substrate W is replaced by the pure water ejected from the rinse liquid nozzle 35. As a result, a liquid film of pure water covering the entire upper surface of the substrate W is formed. When the rinse liquid nozzle 35 ejects pure water, the nozzle moving unit 38 can move the liquid contact position of the pure water relative to the upper surface of the substrate W so that the liquid contact position passes through the central part and the peripheral part, or can keep the liquid contact position stationary at the central part.

[0173] Next, a replacement process is performed ( Fig. 9 In step S4), a replacement liquid that is compatible with both the rinse liquid and the pre-drying treatment liquid is supplied to the upper surface of the substrate W, and the pure water on the substrate W is replaced by the replacement liquid.

[0174] Specifically, when the blocking member 51 is in the upper position and at least one sheath 24 is in the upper position, the nozzle moving unit 46 moves the replacement fluid nozzle 43 from the standby position to the processing position. Thereafter, the replacement fluid valve 45 is opened, and the replacement fluid nozzle 43 starts to spray the replacement fluid (replacement fluid supply process, replacement fluid spraying process). Before starting to spray the replacement fluid, in order to replace the sheath 24 that receives the liquid discharged from the substrate W, the sheath lifting unit 27 may also vertically move at least one sheath 24. When a predetermined time has passed after the replacement fluid valve 45 is opened, the replacement fluid valve 45 is closed, and the spraying of the replacement fluid is stopped. Thereafter, the nozzle moving unit 46 moves the replacement fluid nozzle 43 to the standby position.

[0175] After the replacement liquid ejected from the replacement liquid nozzle 43 collides with the upper surface of the substrate W rotating at a predetermined replacement liquid supply speed, it flows outward along the upper surface of the substrate W due to centrifugal force. The pure water on the substrate W is replaced by the replacement liquid ejected from the replacement liquid nozzle 43. Accordingly, a liquid film of the replacement liquid covering the entire area of ​​the upper surface of the substrate W is formed. When the replacement liquid nozzle 43 ejects the replacement liquid, the nozzle moving unit 46 can move the liquid contact position relative to the liquid contact position of the upper surface of the substrate W through the central part and the peripheral part, or can make the liquid contact position stationary in the central part. In addition, after forming a liquid film of the replacement liquid covering the entire area of ​​the upper surface of the substrate W, the replacement liquid nozzle 43 can be stopped from ejecting the replacement liquid while the substrate W is rotated at an immersion speed (for example, a speed greater than 0 and less than 20 rpm).

[0176] Next, the drying pretreatment liquid supply step ( Fig. 9 In step S5), the drying pre-treatment liquid is supplied to the upper surface of the substrate W, and a liquid film of the drying pre-treatment liquid is formed on the substrate W.

[0177] Specifically, when the blocking member 51 is in the upper position and at least one sleeve 24 is in the upper position, the nozzle moving unit 42 moves the drying pre-processing liquid nozzle 39 from the standby position to the processing position. Thereafter, the drying pre-processing liquid valve 41 is opened, and the drying pre-processing liquid nozzle 39 starts to spray the drying pre-processing liquid (drying pre-processing liquid supply process, drying pre-processing liquid spraying process). Before starting to spray the drying pre-processing liquid, the sleeve lifting unit 27 may also vertically move at least one sleeve 24 in order to replace the sleeve 24 that receives the liquid discharged from the substrate W. When a predetermined time has passed after the drying pre-processing liquid valve 41 is opened, the drying pre-processing liquid valve 41 is closed to stop spraying the drying pre-processing liquid. Thereafter, the nozzle moving unit 42 moves the drying pre-processing liquid nozzle 39 to the standby position.

[0178] After the drying pre-treatment liquid ejected from the drying pre-treatment liquid nozzle 39 collides with the upper surface of the substrate W rotating at a predetermined drying pre-treatment liquid supply speed, it flows outward along the upper surface of the substrate W by centrifugal force. The drying pre-treatment liquid supply speed is, for example, 500 rpm. The replacement liquid on the substrate W is replaced with the drying pre-treatment liquid ejected from the drying pre-treatment liquid nozzle 39. Accordingly, a liquid film (drying pre-treatment liquid film 120) of the drying pre-treatment liquid covering the entire area of ​​the upper surface of the substrate W is formed (drying pre-treatment liquid film forming process). In this way, the drying pre-treatment liquid nozzle 39 is an example of a drying pre-treatment liquid supply unit that supplies the drying pre-treatment liquid to the upper surface of the substrate W in a manner that forms a drying pre-treatment liquid film 120 on the upper surface of the substrate W.

[0179] When the drying pre-treatment liquid nozzle 39 ejects the drying pre-treatment liquid, the nozzle moving unit 42 can move the contact position of the drying pre-treatment liquid with respect to the upper surface of the substrate W so that the contact position passes through the central part and the peripheral part, or can keep the contact position stationary at the central part.

[0180] Next, the film thickness reduction step ( Fig. 9 In step S6), the thickness (film thickness) of the drying pre-treatment liquid film 120 on the substrate W is reduced while maintaining the entire upper surface of the substrate W covered with the liquid film of the drying pre-treatment liquid.

[0181] Specifically, the blocking member lifting unit 54 moves the blocking member 51 from the upper position to the lower position. Then, when the blocking member 51 is in the lower position and at least one sheath 24 is in the upper position, the rotary motor 14 maintains the rotation speed of the substrate W at the film thickness reduction rotation speed. The film thickness reduction rotation speed may be equal to or different from the drying pre-treatment liquid supply speed. After the drying pre-treatment liquid on the substrate W stops spraying, the drying pre-treatment liquid is also discharged from the substrate W to the outside by centrifugal force. Therefore, the thickness of the drying pre-treatment liquid film 120 on the substrate W is reduced. When the drying pre-treatment liquid on the substrate W is discharged to a certain extent, the discharge amount of the drying pre-treatment liquid from the substrate W per unit time is reduced to zero or substantially zero. Accordingly, the thickness of the drying pre-treatment liquid film 120 on the substrate W is stabilized at a value corresponding to the rotation speed of the substrate W.

[0182] Using the film thickness reduction process ( Fig. 9 After reducing the thickness of the pre-drying liquid film 120 in step S6), a first precipitation step (precipitation step) is performed ( Fig. 9 Step S7), the solid 121 of the sublimable substance (refer to Fig. 10B ) is precipitated into the drying pre-treatment liquid on the substrate W.

[0183] Specifically, when the blocking member 51 is in the lower position and at least one sheath 24 is in the upper position, the rotary motor 14 maintains the rotation speed of the substrate W at a predetermined first precipitation speed. The first precipitation speed may be equal to or different from the drying pre-treatment liquid supply speed. The first precipitation speed is, for example, 500 rpm. Since the vapor pressure of the solvent is higher than the vapor pressure of the sublimation substance, during the period when the substrate W rotates at the first precipitation speed, the solvent evaporates from the surface of the drying pre-treatment liquid at an evaporation speed greater than the evaporation speed of the sublimation substance. Fig. 10A Indicates the state in which the solvent evaporates from the surface of the pre-drying treatment liquid.

[0184] If the evaporation of the solvent continues, the thickness of the pre-drying treatment liquid film 120 gradually decreases, and at the same time, the concentration of the sublimable substance on the surface of the pre-drying treatment liquid film 120 and its vicinity gradually increases. The evaporation of the solvent from the pre-drying treatment liquid film 120 is performed, for example, without forcibly heating the pre-drying treatment liquid film 120 on the substrate W. Therefore, the solvent evaporates from the pre-drying treatment liquid while the pre-drying treatment liquid film 120 on the substrate W is maintained at room temperature or a temperature slightly lower than room temperature. When the concentration of the sublimable substance on the surface of the pre-drying treatment liquid film 120 and its vicinity reaches the saturation concentration of the sublimable substance in the pre-drying treatment liquid, as shown in FIG. Fig. 10B As shown, the solid 121 of the sublimable substance is precipitated on the surface of the pre-drying treatment liquid film 120 (room temperature precipitation process, liquid surface precipitation process). In the first precipitation process, the rotary motor 14 functions as a solvent evaporation unit that evaporates the solvent from the pre-drying treatment liquid film 120 in a manner that the solid 121 of the sublimable substance is precipitated.

[0185] like Fig. 10B As shown, when the solid 121 of the sublimable substance precipitates, the main body of the pre-drying treatment liquid, in other words, all or part of the pre-drying treatment liquid in the range from the surface (liquid surface) of the pre-drying treatment liquid film 120 to the upper surface of the pattern PA, becomes the solid 121 of the sublimable substance. Fig. 10B An example is shown in which only the pre-drying liquid on the surface side of the pre-drying liquid film 120 becomes the solid 121 of the sublimable substance, and the remaining pre-drying liquid film 120 is maintained as a liquid. In this example, the solid 121 of the sublimable substance does not reach the upper surface of the pattern PA, and the pre-drying liquid remains not only between the patterns PA, but also between the solid 121 of the sublimable substance and the upper surface of the pattern PA. All or part of the surface of the pre-drying liquid film 120 is covered with the horizontally extending film-shaped solid 121 of the sublimable substance, in other words, is covered with a solid film (solid film).

[0186] Next, the first dissolution step ( Fig. 9 In step S8), the solid 121 of the sublimable substance is dissolved in the drying pre-treatment liquid on the substrate W.

[0187] Specifically, when the blocking member 51 is in the lower position and at least one sheath 24 is in the upper position, the rotary motor 14 maintains the rotation speed of the substrate W at a predetermined first dissolution speed. The first dissolution speed may be equal to or different from the supply speed of the pre-drying treatment liquid. The first dissolution speed is, for example, 500 rpm. Then, the heating fluid valve 73 is opened, and the lower surface nozzle 71 starts to spray warm water (pure water with a temperature higher than room temperature). Before starting to spray warm water, the sheath lifting unit 27 may also vertically move at least one sheath 24 in order to replace the sheath 24 that receives the liquid discharged from the substrate W.

[0188] After the warm water ejected from the lower surface nozzle 71 collides with the central portion of the lower surface of the substrate W rotating at the first dissolution speed, it flows outward along the lower surface of the substrate W. Accordingly, the entire area of ​​the substrate W is heated at a heating temperature higher than the room temperature. The heat of the warm water is transferred to the drying pre-treatment liquid on the substrate W via the substrate W. The drying pre-treatment liquid film 120 on the substrate W is indirectly heated via the substrate W (indirect heating process). Accordingly, the temperature of the sublimable substance solid 121 and the drying pre-treatment liquid film 120 on the substrate W is maintained at a temperature higher than the room temperature.

[0189] like Fig. 10C As shown in FIG. 1 , when the temperature of the pre-drying treatment liquid film 120 on the substrate W is increased, the saturation concentration of the sublimable substance in the pre-drying treatment liquid increases, and the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid on the substrate W. The dissolution of the solid 121 of the sublimable substance in the pre-drying treatment liquid is promoted by the increase in the temperature of the pre-drying treatment liquid. Accordingly, all or most of the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid on the substrate W. Fig. 10D An example is shown in which the solid 121 of the sublimable substance is completely dissolved in the pre-drying treatment liquid.

[0190] After dissolving the solid 121 of the sublimable substance in the pre-drying treatment liquid, the solid 121 of the sublimable substance may be precipitated again, and the precipitated solid 121 of the sublimable substance may be dissolved in the pre-drying treatment liquid again. In other words, the first precipitation step ( Fig. 9 Step S7) to the first dissolution step ( Fig. 9 1 repeated cycle from step S8) to step S8).

[0191] Fig. 9 "N" in the above is an integer greater than 0. When N is greater than 1, the cycle is repeated two or more times, and then the final precipitation step ( Fig. 9 In the case where N is 0, the first precipitation step ( Fig. 9 Step S7) and the first dissolution step ( Fig. 9Then, a final precipitation step ( Fig. 9 Step S9).

[0192] Specifically, when the blocking member 51 is in the lower position and at least one of the sheaths 24 is in the upper position, the rotating motor 14 maintains the rotation speed of the substrate W at a predetermined final precipitation speed. The final precipitation speed may be equal to or different from the supply speed of the pre-drying treatment liquid. The final precipitation speed is, for example, 500 rpm. The warm water is sprayed from the lower surface nozzle 71 from the first dissolution step ( Fig. 9 Therefore, the drying pre-treatment liquid on the substrate W is also maintained at a temperature higher than the room temperature during the period when the substrate W is rotated at the final deposition speed.

[0193] like Fig. 10D As shown, during the period when the substrate W rotates at the final precipitation speed, the solvent evaporates from the surface of the drying pre-treatment liquid film 120. Therefore, the surface of the drying pre-treatment liquid gradually approaches the base of the pattern PA, and the concentration of the sublimable substance in the drying pre-treatment liquid film 120 gradually increases. When the concentration of the sublimable substance in the drying pre-treatment liquid film 120 reaches the saturation concentration of the sublimable substance in the drying pre-treatment liquid, the solid 121 of the sublimable substance is precipitated on the upper surface of the substrate W, and all or almost all of the drying pre-treatment liquid disappears from the substrate W. In the final precipitation step, the rotary motor 14 and the lower surface nozzle 71 function as a solvent evaporation unit that evaporates the solvent from the drying pre-treatment liquid film 120 in a manner that the solid 121 of the sublimable substance is precipitated.

[0194] Fig. 10E An example is shown in which all the pre-drying treatment liquid disappears and the solid 121 of the sublimable substance is precipitated between the patterns PA. Fig. 10E An example is shown in which the thickness of the solid 121 of the sublimable substance is larger than the height of the pattern PA.

[0195] Fig.11 This is the equilibrium diagram of camphor and IPA. The solution of camphor and IPA is equivalent to the pre-drying treatment solution. Fig.11 The curve in (freezing curve) represents the freezing point of the solution of camphor and IPA. Fig.11 The bold line in the figure indicates that the first precipitation step is performed once ( Fig. 9 Step S7), the first dissolution step ( Fig. 9 Step S8) and the final precipitation step ( Fig. 9 In step S9), that is, Fig. 9 The concentration of camphor and the temperature of the solution when N=0.

[0196] exist Fig.11In the example, the thick straight line from point P1 to point P2 indicates that the first precipitation step ( Fig. 9 Step S8). Perform the first precipitation step ( Fig. 9 In step S8), IPA evaporates from the solution of camphor and IPA, which is equivalent to the pre-drying treatment liquid, and the concentration of camphor gradually increases. At this time, the temperature of the pre-drying treatment liquid is maintained at room temperature or a temperature near room temperature. When the concentration of camphor rises to Fig.11 When the concentration reaches point P2 in the reaction mixture, a solid 121 of a sublimable substance including camphor and IPA is formed by precipitation or solidification.

[0197] exist Fig.11 In the example, the thick straight line from point P2 to point P3 indicates that the first dissolution step ( Fig. 9 Step S8). Perform the first dissolution step ( Fig. 9 In step S8), the temperature of the solution of camphor and IPA rises, and the temperature of the solid 121 of the sublimable substance rises to a temperature higher than the freezing point of the solution of camphor and IPA. Accordingly, at least a portion of the solid 121 of the sublimable substance melts or dissolves and returns to the solution of camphor and IPA.

[0198] exist Fig.11 In the example, the thick straight line from point P3 to point P4 indicates the final precipitation step ( Fig. 9 As described above, the final precipitation step ( Fig. 9 In step S9), in order to precipitate the solid 121 of the sublimable substance again, the temperature of the camphor and IPA solution is not lowered, but the camphor and IPA solution is maintained at a temperature higher than room temperature while the IPA is further evaporated. Fig. 9 The solid 121 of the sublimable substance precipitated in step S7) is a solid 121 of the sublimable substance having a smaller content of IPA than that precipitated.

[0199] After the solid 121 of the sublimable substance is precipitated between the patterns PA, a sublimation process is performed ( Fig. 9 In step S10), the solid 121 of the sublimable substance is sublimated and removed from the upper surface of the substrate W.

[0200] Specifically, when the blocking member 51 is in the lower position, the rotary motor 14 maintains the rotation speed of the substrate W at a predetermined sublimation speed. The sublimation speed may be equal to or different from the supply speed of the drying pretreatment liquid. The sublimation speed is, for example, 1500 rpm. Then, the upper gas valve 57 is opened, and the central nozzle 55 starts to spray nitrogen. In addition to or instead of opening the upper gas valve 57, the opening of the flow regulating valve 65 may be changed to increase the flow rate of the nitrogen gas sprayed from the upper central opening 61 of the blocking member 51.

[0201] When the rotation of the substrate W at the sublimation speed starts, the sublimation of the solid 121 of the sublimable substance on the substrate W starts, and a gas containing the sublimable substance is generated from the solid 121 of the sublimable substance on the substrate W. The gas generated from the solid 121 of the sublimable substance (gas containing the sublimable substance) flows radially in the space between the substrate W and the shielding member 51, and is exhausted from above the substrate W. Then, when a certain period of time has passed since the start of sublimation, as shown in FIG. Fig.10F As shown, all the solids 121 of the sublimable substance are removed from the substrate W. Thereafter, the rotation motor 14 is stopped to stop the rotation of the substrate W. Furthermore, the upper gas valve 57 is closed, and the central nozzle 55 stops ejecting nitrogen gas.

[0202] In this way, the central nozzle 55 , the upper central opening 61 of the blocking member 51 , and the rotary motor 14 function as a sublimation unit that sublimates the solid 121 of the sublimable substance on the upper surface of the substrate W.

[0203] It should be noted that, instead of ejecting the nitrogen gas, a heat source such as a heating element or a lamp may be disposed above or below the substrate W, and the sublimable substance may be sublimated by heating using the heat source.

[0204] In addition, although it will be described below, when the solid 121 of the sublimable substance on the substrate W is precipitated, the detection value of the film thickness measuring unit 91 changes significantly, so the controller 3 can determine whether the solid 121 of the sublimable substance is precipitated by monitoring the detection value of the film thickness measuring unit 91. Therefore, the controller 3 can also control in the following manner: a threshold value is pre-set for the film thickness at any position in the upper surface of the substrate W measured by the film thickness measuring unit 91, and if the measured film thickness becomes below the threshold value, the process is transferred from the final precipitation process to the sublimation process.

[0205] Next, carry out the unloading process ( Fig. 9 In step S11), the substrate W is moved out of the chamber 4.

[0206] Specifically, the shielding member lifting unit 54 raises the shielding member 51 to the upper position, and the sheath lifting unit 27 lowers all the sheaths 24 to the lower position. Then, the upper gas valve 64 and the lower gas valve 84 are closed, and the upper central opening 61 of the shielding member 51 and the lower central opening 81 of the rotating base 12 stop spraying nitrogen. Thereafter, the central robot CR causes the hand H1 to enter the chamber 4. After the plurality of chuck pins 11 release the substrate W from being held, the central robot CR uses the hand H1 to support the substrate W on the rotating chuck 10. Thereafter, the central robot CR uses the hand H1 to support the substrate W while withdrawing the hand H1 from the interior of the chamber 4. In this way, the processed substrate W is carried out of the chamber 4.

[0207] Next, an example of substrate processing (second substrate processing example) in which the drying pre-processing liquid is a solution of camphor and methanol will be described.

[0208] The general process of the second substrate processing example is the same as that of the first substrate processing example. Fig. 9 As shown. For the second substrate processing example, from the first dissolution step ( Fig. 9 Step S8) to the final precipitation step ( Fig. 9 The steps from step S9) to step S9) are different from those in the first substrate processing example, and the other steps are the same as those in the first substrate processing example. Therefore, the steps from the first dissolution step to the final precipitation step in the second substrate processing example are described below.

[0209] FIG. 12A to FIG. 12D Schematic diagram showing the state of the substrate W when a solution of camphor and methanol is used. Figure 2 and Fig. 9 .about FIG. 12A to FIG. 12D , with appropriate reference.

[0210] Using the first precipitation step ( Fig. 9 After the solid 121 of the sublimable substance is precipitated in step S7), the first dissolution step ( Fig. 9 In step S8), the solid 121 of the sublimable substance is dissolved in the drying pre-treatment liquid on the substrate W.

[0211] Specifically, when the blocking member 51 is in the lower position and at least one sheath 24 is in the upper position, the rotary motor 14 maintains the rotation speed of the substrate W at a predetermined first dissolution speed. The first dissolution speed may be equal to or different from the supply speed of the pre-drying treatment liquid. The first dissolution speed is, for example, 1500 rpm. When the substrate W rotates at the first dissolution speed, in order to stop the nitrogen gas from being ejected from the upper central opening 61 of the blocking member 51, the controller 3 may also close the upper gas valve 64. Alternatively, the controller 3 may also reduce the flow rate of the nitrogen gas ejected from the upper central opening 61 of the blocking member 51 by changing the opening of the flow regulating valve 65.

[0212] In the first precipitation step ( Fig. 9 When the solvent is evaporated from the pre-drying liquid in step S7), the heat of the pre-drying liquid equivalent to the heat of vaporization is released into the gas atmosphere in the chamber 4 together with the solvent, and the surface temperature of the pre-drying liquid decreases. When the solid 121 of the sublimable substance is formed, the amount of solvent evaporated from the pre-drying liquid decreases, and therefore the heat of the pre-drying liquid released into the gas atmosphere also decreases. At the same time, Fig. 12AAs shown, the heat in the gas atmosphere is transferred to the pre-drying treatment liquid via the sublimable substance solid 121. As a result, the temperature of the sublimable substance solid 121 and the pre-drying treatment liquid film 120 on the substrate W rises.

[0213] When the temperature of the sublimable solid 121 and the pre-drying treatment liquid film 120 on the substrate W rises, Fig. 12B As shown, a part of the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid. The pre-drying treatment liquid is a solution of camphor and methanol. The solid 121 of the sublimable substance contains camphor. The solubility of camphor in methanol is greater than the solubility of camphor in IPA, and camphor is easily soluble in methanol. When a part of the solid camphor is dissolved in the liquid of methanol, the remaining solid camphor is also immediately dissolved in the liquid of methanol. Accordingly, all or most of the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid on the substrate W. Fig. 12C This shows an example in which the solid 121 of the sublimable substance is completely dissolved in the pre-drying treatment liquid.

[0214] When the solid 121 of the sublimable substance dissolves in the pre-drying treatment liquid on the substrate W, the amount of solvent evaporated from the pre-drying treatment liquid increases, and the surface temperature of the pre-drying treatment liquid decreases. Fig.12D As shown, the concentration of the sublimable substance on the surface of the pre-drying treatment liquid increases, and the solid 121 of the sublimable substance is precipitated again on the surface of the pre-drying treatment liquid ( Fig. 9 Step S7). When the solid 121 of the sublimable substance precipitates again, as described above, the temperature of the solid 121 of the sublimable substance and the pre-drying treatment liquid rises, and the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid ( Fig. 9 Step S8).

[0215] Thus, when the pre-drying treatment liquid is a solution of camphor and methanol, even if the temperature of the pre-drying treatment liquid is not forcibly changed, the solid 121 of the sublimable substance can be repeatedly precipitated and dissolved (natural precipitation step, natural dissolution step) simply by placing the pre-drying treatment liquid on the upper surface of the substrate W. Fig. 9 Step S7) to the first dissolution step ( Fig. 9 The number of repetitions of 1 repetition cycle from step S8) to the drying pre-treatment liquid increases with the increase of the standing time. Therefore, as long as the precipitation and dissolving repetitions of the solid 121 of the sublimable substance are set according to the allowed time.

[0216] When the solid 121 of the sublimable substance is precipitated, the vapor pressure of the solvent in the gas atmosphere in contact with the pre-drying treatment liquid on the substrate W is maintained to be less than the saturated vapor pressure of the solvent at the temperature of the gas atmosphere. When the solid 121 of the sublimable substance is dissolved, the temperature of the interface between the solid 121 of the sublimable substance and the pre-drying treatment liquid film 120 is maintained to be a value exceeding the freezing point of the pre-drying treatment liquid at the concentration of the sublimable substance when the solid 121 of the sublimable substance is dissolved. In this way, the precipitation and dissolution of the solid 121 of the sublimable substance are naturally repeated.

[0217] When the solid 121 of the sublimable substance is precipitated and dissolved, the controller 3 may also cause at least one of the central nozzle 55 and the upper central opening 61 of the blocking member 51 to eject gas such as nitrogen at a low flow rate. In this case, the vapor of the solvent can be quickly removed from the top of the substrate W, which can promote the evaporation of the solvent. Furthermore, as long as the gas is ejected at a low flow rate to the upper surface of the substrate W, the temperature change of the interface between the solid 121 of the sublimable substance and the pre-drying treatment liquid film 120 can be suppressed to a minimum. Therefore, the evaporation of the solvent can be promoted without hindering the dissolution of the solid 121 of the sublimable substance.

[0218] The FFU 6 always supplies clean air into the chamber 4. The downflow of the clean air flowing toward the upper surface of the substrate W is blocked by the blocking member 51. Accordingly, the disorder of the gas atmosphere on the substrate W can be suppressed. The controller 3 can also temporarily stop the supply of clean air by the FFU 6 when the solid 121 of the sublimable substance is precipitated and dissolved. In addition, in order to suppress the disorder of the gas atmosphere on the substrate W, the controller 3 can also temporarily stop the rotation of the substrate W by the rotary motor 14 when the solid 121 of the sublimable substance is precipitated and dissolved.

[0219] After the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid, a final precipitation step ( Fig. 9 In step S9), the solid 121 of the sublimable substance is precipitated again.

[0220] Specifically, when the blocking member 51 is in the lower position and at least one sheath 24 is in the upper position, the rotating motor 14 maintains the rotation speed of the substrate W at a predetermined final precipitation speed. The final precipitation speed may be equal to or different from the supply speed of the pre-drying treatment liquid. The final precipitation speed is, for example, 1500 rpm. While the substrate W rotates at the final precipitation speed, the solvent evaporates from the surface of the pre-drying treatment liquid. When the concentration of the sublimable substance in the pre-drying treatment liquid reaches the saturation concentration of the sublimable substance in the pre-drying treatment liquid, the solid 121 of the sublimable substance precipitates on the upper surface of the substrate W, and all or almost all of the pre-drying treatment liquid disappears from the substrate W (refer to Fig.10E). Thereafter, a sublimation step is performed to sublime the solid 121 of the sublimable substance on the substrate W ( Fig. 9 Step S10).

[0221] As described above, when the drying pre-treatment liquid is a solution of camphor and methanol, the precipitation and dissolution of the solid 121 of the sublimable substance are repeated only by placing the drying pre-treatment liquid on the upper surface of the substrate W. When a trace amount of the drying pre-treatment liquid remains on the substrate W, the solid 121 of the sublimable substance may be dissolved in the drying pre-treatment liquid before the solid 121 of the sublimable substance is sublimated. In order to prevent this, the solid 121 of the sublimable substance on the substrate W may also be cooled. For example, the rotation speed of the substrate W may be increased, and the flow rate of the gas ejected to the upper surface of the substrate W may also be increased.

[0222] Fig.13 : is a graph showing the failure rate of pattern PA. Failure rate A and failure rate B are values ​​when the pre-drying treatment liquid is a solution of camphor and IPA, and failure rate C is a value when the pre-drying treatment liquid is a solution of camphor and methanol.

[0223] "Failure rate A" and Fig. 9 The substrate treatment shown is different, and is a value when the solid 121 of the sublimable substance is precipitated once and then the solid 121 of the sublimable substance is sublimated. The "destruction rate B" is a value when the solid 121 of the sublimable substance is precipitated twice and then the solid 121 of the sublimable substance is sublimated. That is, the "destruction rate B" is Fig. 9 The failure rate is the failure rate when N=0. The "failure rate C" is the value when the solid 121 of the sublimable substance is precipitated more than 2 times and then the solid 121 of the sublimable substance is sublimated. Except for the composition of the drying pretreatment liquid and the number of times the solid 121 of the sublimable substance is precipitated, the processing conditions of the substrate W in the failure rates A to C are the same.

[0224] The failure rate A is lower than the value when IPA drying is performed, wherein the IPA drying dries the substrate W by removing the IPA on the substrate W by high-speed rotation of the substrate W. The failure rate B is lower than the failure rate A. Similarly, the failure rate C is lower than the failure rate A. The failure rate C is lower than the failure rate B. The failure rate B is less than half of the failure rate A. The failure rate C is less than half of the failure rate B. The failure rate C is less than 1%, which is extremely low.

[0225] Since the failure rate B is lower than the failure rate A, the failure rate of the pattern PA can be reduced by dissolving the precipitated sublimation substance solid 121 in the drying pretreatment liquid and then precipitating the sublimation substance solid 121 again. Since the failure rate C is lower than the failure rate B, when the sublimation substance is camphor, the failure rate of the pattern PA can be further reduced by using methanol as a solvent instead of IPA. Therefore, even when the strength of the pattern PA is extremely low, as long as the first precipitation step ( Fig. 9 Step S7) and the first dissolution step ( Fig. 9 Repeating the step S8) for more than one time can reduce the failure rate of the pattern PA. Fig. 9 When N=0, the failure rate of pattern PA can also be reduced.

[0226] According to the research of the present inventors, in the interval G1 of the pattern PA (refer to Fig. 10A ) is less than 30nm, there is a case where a good failure rate of the pattern PA cannot be obtained even if sublimation drying is performed. It is believed that the reason is that an incomplete precipitation area where the solid 121 of the sublimable substance does not exist or hardly exists between the patterns PA is formed in the upper surface of the substrate W. Therefore, as long as the precipitated solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid and then the solid 121 of the sublimable substance is precipitated again, the failure rate of the pattern PA can be reduced even on the substrate W where the interval G1 of the pattern PA is less than 30nm.

[0227] Next, a change in the thickness of the pre-drying treatment liquid film 120 will be described.

[0228] Fig.14 1 is a graph showing the change over time in the thickness of the pre-drying treatment liquid film 120 on the upper surface of the substrate W until the solid 121 of the sublimable substance is precipitated from the pre-drying treatment liquid. Fig.14 The aspect ratio of the inset in Fig.14 The other parts are different.

[0229] Fig.14 The multiple curves (solid line curve, single-point dash line curve, dotted line curve) in FIG. 1 are film thickness curves showing the measured values ​​when using multiple drying pretreatment solutions with different concentrations of sublimable substances. Except for the concentration of the sublimable substance, the conditions of each measurement are the same. Fig.14 As shown, regardless of the concentration of the sublimable substance, when the solid 121 of the sublimable substance is precipitated from the pre-drying treatment liquid, the thickness of the pre-drying treatment liquid film 120 decreases with the passage of time.

[0230] exist Fig.14In the embodiment, the thickness of the pre-drying treatment liquid film 120 is measured only until the time T1. The reason is that at the time T1, the solid 121 of the sublimable substance is precipitated. In other words, the pre-drying treatment liquid is transparent, and the transparency of the solid 121 of the sublimable substance is lower than that of the pre-drying treatment liquid. Therefore, when the solid 121 of the sublimable substance is precipitated, the detection value of the film thickness measuring unit 91 changes significantly, and the thickness of the pre-drying treatment liquid film 120 cannot be measured.

[0231] When the solid 121 of the sublimable substance is precipitated, the detection value of the film thickness measuring unit 91 changes significantly, so the controller 3 can determine whether the solid 121 of the sublimable substance is precipitated by monitoring the detection value of the film thickness measuring unit 91. Furthermore, the thickness of the pre-drying treatment liquid film 120 just before the solid 121 of the sublimable substance is about to precipitate is substantially equal to the thickness of the solid 121 of the sublimable substance just after the solid 121 of the sublimable substance is precipitated. Therefore, the controller 3 can also measure the thickness of the solid 121 of the sublimable substance by measuring the thickness of the pre-drying treatment liquid film 120.

[0232] In addition, if Fig.14 As shown, regardless of the concentration of the sublimable substance, the film thickness of the pre-drying treatment liquid decreases sharply, and then decreases slowly. During the period when the thickness of the pre-drying treatment liquid film 120 decreases sharply, the thickness of the pre-drying treatment liquid film 120 and the film thickness reduction rate are almost the same in a plurality of pre-drying treatment liquids with different concentrations of the sublimable substance. In other words, as long as the elapsed time is the same, the thickness of the pre-drying treatment liquid film 120 decreases at a substantially same reduction rate regardless of the concentration of the sublimable substance.

[0233] In contrast, Fig.14 As shown in the inset diagram in FIG, during the period when the thickness of the pre-drying treatment liquid film 120 is slowly reduced, the film thickness reduction rate is different in a plurality of pre-drying treatment liquids having different concentrations of the sublimable substance. The reason is believed to be that if the concentration of the sublimable substance changes, the viscosity of the pre-drying treatment liquid changes.

[0234] Specifically, the higher the concentration of the sublimable substance in the pre-drying treatment liquid, the higher the viscosity of the pre-drying treatment liquid. The higher the viscosity of the pre-drying treatment liquid, the more difficult it is to discharge it to the outside of the substrate W using the centrifugal force generated by the rotation of the substrate W. Therefore, the higher the concentration of the sublimable substance in the pre-drying treatment liquid, the smaller the slope of the curve. In other words, the higher the concentration of the sublimable substance in the pre-drying treatment liquid, the slower the film thickness reduction rate during the period when the thickness of the pre-drying treatment liquid film 120 is slowly reduced. Therefore, during Fig.14In the inset diagram in , the concentration of the sublimable substance in the pre-drying treatment liquid shown by the solid line is the lowest, the concentration of the sublimable substance in the pre-drying treatment liquid shown by the dotted line is the second lowest, and the concentration of the sublimable substance in the pre-drying treatment liquid shown by the single-point chain line is the highest. That is, there is a correlation between the film thickness reduction rate and the concentration of the sublimable substance in the pre-drying treatment liquid.

[0235] Therefore, as long as the film thickness reduction speeds of a plurality of pre-drying treatment liquid films 120 having different concentrations of sublimable substances are measured in advance and prepared as reference data SD, the concentration of the sublimable substance in the pre-drying treatment liquid on the substrate W can be estimated based on the film thickness reduction speed by monitoring the thickness of the pre-drying treatment liquid film 120 on the substrate W. The reference data SD is stored, for example, in the main storage device 3c of the controller 3 (see Figure 8 ) In order to compare with the film thickness reduction rate obtained by monitoring the thickness of the dried pre-processing liquid film 120 on the substrate W during substrate processing, the reference data SD stored in the main storage device 3c is referred to at any time.

[0236] If the thickness of the pre-drying treatment liquid film 120 before the solid 121 of the sublimable substance is the same, the thickness of the solid 121 of the sublimable substance increases with the increase of the concentration of the sublimable substance, and decreases with the decrease of the concentration of the sublimable substance. Therefore, by measuring the thickness of the pre-drying treatment liquid film 120 and estimating the actual concentration of the sublimable substance, the thickness of the solid 121 of the sublimable substance can be estimated before the solid 121 of the sublimable substance is precipitated.

[0237] Fig.15 1 is a flowchart showing the first example of the film thickness monitoring process. Figure 2 and Fig.15 The film thickness monitoring step is performed, for example, together with the first precipitation step (step S7) (see Fig. 9 ). That is, the film thickness monitoring step is performed only when the solid 121 of the sublimable substance is precipitated for the first time.

[0238] When the thickness of the pre-drying treatment liquid film 120 is measured, the controller 3 determines whether the first precipitation step (precipitation step) is started ( Fig.15 The determination of whether the first precipitation step is started is performed based on, for example, whether the pre-drying treatment liquid valve 41 is opened, that is, whether the discharge of the pre-drying treatment liquid is stopped.

[0239] When the first precipitation step is not started ( Fig.15 In step S21, the answer is No), that is, when the ejection of the drying pre-treatment liquid is stopped, the controller 3 determines whether the first precipitation step is started after a predetermined time has passed ( Fig.15If the first precipitation step has started (at step S21). Fig.15 In step S21, if it is YES), that is, if the ejection of the pre-drying treatment liquid has been stopped, the controller 3 causes the film thickness measuring unit 91 to start measuring the film thickness of the pre-drying treatment liquid (film thickness measuring step, Fig.15 Step S22).

[0240] While the film thickness measuring unit 91 measures the thickness of the pre-drying treatment liquid film 120 , the controller 3 also measures the film thickness reduction rate of the pre-drying treatment liquid film 120 based on the thickness of the pre-drying treatment liquid film 120 (film thickness reduction rate measuring step).

[0241] The reference speed range indicating the range of the appropriate film thickness reduction speed is specified by the processing scheme based on the reference concentration range indicating the appropriate concentration of the sublimable substance in the liquid film of the pre-drying treatment liquid and the reference data SD. The controller 3 determines whether the film thickness reduction speed is appropriate before the concentration of the sublimable substance in the pre-drying treatment liquid film 120 reaches the saturation concentration. In other words, it determines whether the film thickness reduction speed is within the reference speed range (reduction speed determination process, Fig.15 According to this, it is substantially possible to determine whether the concentration of the solid of the sublimable substance in the pre-drying treatment liquid film 120 is within the reference concentration range (concentration determination step).

[0242] When the film thickness reduction speed is appropriate, in other words, when the film thickness reduction speed is greater than the lower limit value of the reference speed range and less than the upper limit value of the reference speed range (in Fig.15 In step S23, if it is Yes), the controller 3 determines the first precipitation step ( Fig. 9 In step S8), whether the solid 121 of the sublimable substance is precipitated ( Fig.15 If the solid 121 of the sublimable substance is not precipitated (in Fig.15 In step S24, the answer is No), the controller 3 determines again after a predetermined time whether the reduction speed of the film thickness is appropriate ( Fig.15 Step S23).

[0243] If the solid 121 of the sublimable substance has precipitated (in Fig.15 In step S24 of , if it is YES), the controller 3 determines whether the thickness of the solid 121 of the sublimable substance is appropriate based on the measured value of the film thickness measuring unit 91 before the solid 121 of the sublimable substance is about to precipitate, that is, when the concentration of the sublimable substance in the pre-drying treatment liquid film 120 reaches the saturation concentration. In other words, the controller 3 determines whether the thickness of the solid 121 of the sublimable substance exceeds the lower limit value of the reference thickness range and is less than the upper limit value of the reference thickness range (thickness determination process, Fig.15Step S25).

[0244] If the thickness of the solid 121 of the sublimable substance is appropriate (in Fig.15 In step S25, if it is YES), the controller 3 causes the film thickness measuring unit 91 to stop measuring the thickness of the pre-drying treatment liquid film 120 ( Fig.15 If the thickness of the solid 121 of the sublimable substance is not appropriate (in Fig.15 In step S25, the result is No), the controller 3 makes the alarm device 100C (refer to Figure 8 ) generates an alarm (second abnormality notification process, Fig.15 Then, the measurement of the thickness of the pre-drying treatment liquid film 120 by the film thickness measuring unit 91 is stopped ( Fig.15 Step S26).

[0245] Because the first flow control valve 107A or the second flow control valve 107B (see Figure 7 ) causes the concentration of the sublimable substance to be outside the reference concentration range, and the film thickness reduction rate is greater than the upper limit of the reference speed range, or the film thickness reduction rate is less than the lower limit of the reference speed range (in Fig.15 In step S23, the result is No), the controller 3 makes the alarm device 100C (refer to Figure 8 ) generates an alarm (the first abnormality notification process, Fig.15 Step S28).

[0246] Thereafter, the controller 3 starts the drying pre-treatment liquid removal step before the solid 121 of the sublimable substance is precipitated, and removes the drying pre-treatment liquid ( Fig.15 The details of the drying pre-treatment liquid removal process are as follows. Then, the controller 3 causes the film thickness measuring unit 91 to stop measuring the film thickness of the drying pre-treatment liquid ( Fig.15 Step S26).

[0247] When the substrate processing is not interrupted, the first precipitation step ( Fig. 9 After the step S7) and the film thickness monitoring step, the first dissolution step ( Fig. 9 In step S8 of the present invention, when the pre-drying treatment liquid is a solution of a sublimable substance and IPA, the substrate W is heated in order to dissolve the precipitated solid 121 of the sublimable substance in the pre-drying treatment liquid. Then, after repeating the first precipitation step and the first dissolution step for a predetermined number of times, the final precipitation step is performed, and finally the sublimation step is performed. Fig. 9 When N=0, the first precipitation step and the first dissolution step are not repeated, but the final precipitation step is performed, and finally the sublimation step is performed.

[0248] That is, when it is determined in the concentration determination step that the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is within the reference concentration range, the sublimation step is performed after the final precipitation step is completed.

[0249] Fig.16 This is a schematic diagram for explaining an example of the drying pre-treatment liquid removal step in the first example of the film thickness monitoring step.

[0250] As described above, the controller 3 measures the decreasing speed ( ) of the thickness of the pre-drying treatment liquid film 120 in order to determine whether the concentration of the sublimable substance contained in the pre-drying treatment liquid film 120 is appropriate. Fig.15 The reason is that if the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is abnormal, that is, if the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is outside the reference concentration range, the final precipitation step ( Fig. 9 The thickness of the solid 121 of the sublimable substance precipitated in step S9) may be greater or less than the intended value. If the thickness of the solid 121 of the sublimable substance immediately before sublimation is greater or less than the intended value, the failure rate of the pattern PA may be deteriorated.

[0251] Therefore, the controller 3 implements Fig.16 The drying pretreatment liquid removal step ( Fig.15 Step S29). Fig.16 The replacement liquid nozzle 43 is shown to discharge a solvent corresponding to the replacement liquid onto the upper surface of the substrate W. Fig.16 The example in which the pre-drying treatment liquid is a solution of camphor and IPA and the solvent is IPA is shown. When the pre-drying treatment liquid is a solution of camphor and methanol, methanol is ejected from the replacement liquid nozzle 43 instead of IPA.

[0252] When the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is abnormal, such as Fig.16 As shown, the controller 3 may also cause the replacement liquid nozzle 43 to eject the solvent. In this case, the drying pre-treatment liquid on the substrate W is replaced with the solvent to form a liquid film of the solvent covering the entire area of ​​the upper surface of the substrate W. Therefore, before the solid 121 of the sublimable substance is precipitated, the drying pre-treatment liquid with an inappropriate concentration of the sublimable substance can be removed from the substrate W. That is, when it is determined in the concentration determination process that the concentration of the sublimable substance in the drying pre-treatment liquid film 120 is not within the reference concentration range, the drying pre-treatment liquid removal process is performed, and the solvent as the removal liquid is supplied to the upper surface of the substrate W before the solid 121 of the sublimable substance is precipitated in the first precipitation process, thereby removing the drying pre-treatment liquid from the upper surface of the substrate W.

[0253] Thus, when the drying pretreatment liquid is a solution of camphor and IPA, in the drying pretreatment liquid removal step, IPA plays a role as a removal liquid for removing the drying pretreatment liquid from the upper surface of the substrate W. When the drying pretreatment liquid is a solution of camphor and methanol, in the drying pretreatment liquid removal step, methanol plays a role as a removal liquid. The removal liquid is preferably a liquid of the same type as the solvent used in the drying pretreatment liquid, but is not limited thereto. The removal liquid may be a liquid of a different type from the solvent of the drying pretreatment liquid as long as it is compatible with the drying pretreatment liquid.

[0254] The controller 3 interrupts the first precipitation step and starts the drying pretreatment liquid removal step ( Fig.15 After step S29), the controller 3 causes the film thickness measuring unit 91 to stop measuring the thickness of the pre-drying treatment liquid film 120 ( Fig.15 Step S26).

[0255] In the substrate processing of the present embodiment, when the solid 121 of the sublimable substance begins to precipitate in the first precipitation process, the drying pre-treatment liquid remains on the upper surface of the substrate W. In the first dissolution process, at least a portion of the solid 121 of the sublimable substance is dissolved in the drying pre-treatment liquid. Thereafter, in the final precipitation process, the solvent is evaporated again from the drying pre-treatment liquid. Accordingly, the content of the solvent is reduced, and the solid 121 of the sublimable substance is precipitated on the upper surface of the substrate W. Thereafter, the solid 121 of the sublimable substance is sublimated and removed from the substrate W. In this way, the drying pre-treatment liquid is removed from the substrate W, and the substrate W is dried.

[0256] Before the solid 121 of the sublimable substance is precipitated for the first time, the pre-drying treatment liquid exists not only between the patterns PA, but also above the patterns PA. In a substrate W such as a semiconductor wafer or an FPD substrate, the interval G1 of the patterns PA is narrow. When the interval G1 of the patterns PA is narrow, the properties of the pre-drying treatment liquid existing between the patterns PA are different from those of the main body of the pre-drying treatment liquid, in other words, the pre-drying treatment liquid located in the range from the surface (upper surface) of the pre-drying treatment liquid film 120 to the upper surface of the pattern PA. The difference in the properties of the two becomes significant as the interval G1 of the pattern PA becomes narrower.

[0257] If the interval G1 of the pattern PA is narrow, the following situation may occur: when the solid 121 of the sublimable substance is precipitated for the first time, the solid 121 of the sublimable substance is precipitated only in the main body of the pre-drying treatment liquid, and an incomplete precipitation area where the solid 121 of the sublimable substance does not exist or hardly exists between the patterns PA is formed on the upper surface of the substrate W. In this case, the surface tension of the pre-drying treatment liquid between the patterns PA is applied to the side of the pattern PA, so when the solid 121 of the sublimable substance is sublimated, the pattern PA in the incomplete precipitation area may be damaged. This causes the damage rate of the pattern PA to increase (deteriorate).

[0258] On the other hand, if the precipitated sublimation substance solid 121 is precipitated again after being dissolved in the pre-drying treatment liquid, the crystal nucleus of the sublimation substance solid 121 is also formed in a narrow space such as the space between the patterns PA. Therefore, as long as the precipitated sublimation substance solid 121 is precipitated again after being dissolved in the pre-drying treatment liquid, even when the interval G1 of the pattern PA is narrow, the generation of the incomplete precipitation area can be prevented or its area can be reduced. Accordingly, the failure rate of the pattern PA can be reduced.

[0259] The thickness of the solid 121 of the sublimable substance is substantially the same as the thickness of the pre-drying treatment liquid film 120 when the saturated concentration of the sublimable substance is reached. If the concentration of the sublimable substance in the pre-drying treatment liquid film 120 reaches the saturated concentration of the sublimable substance, the solid 121 of the sublimable substance will precipitate immediately thereafter. Therefore, as long as the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is known before the concentration of the sublimable substance in the pre-drying treatment liquid film 120 reaches the saturated concentration of the sublimable substance, the thickness of the solid 121 of the sublimable substance can be predicted, and the formation of the solid 121 of the sublimable substance of inappropriate thickness can be avoided.

[0260] Generally, in order to measure the concentration of a substance in a liquid, it is necessary to bring a concentration measuring instrument (not shown) into contact with the liquid. Since the pre-drying liquid film 120 formed on the substrate W is relatively thin, it is difficult to bring the concentration measuring instrument into contact with the pre-drying liquid film 120 without bringing the pre-drying liquid film 120 into contact with the upper surface of the substrate W. Therefore, there is a risk of damaging the pattern PA formed on the upper surface of the substrate.

[0261] As described above, the inventors of the present application have found that there is a correlation between the film thickness reduction rate and the concentration of the sublimable substance in the pre-drying treatment liquid film 120. In the present embodiment, before the solid 121 of the sublimable substance is precipitated in the first precipitation step, it is determined whether the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is within the reference concentration range based on the film thickness reduction rate of the pre-drying treatment liquid film 120 (concentration determination step).

[0262] Specifically, by continuously measuring the thickness of the pre-drying treatment liquid film 120 for a predetermined time using the film thickness measuring unit 91, the thickness reduction rate of the pre-drying treatment liquid film 120 in the first precipitation step can be measured. Therefore, the controller 3 can substantially determine whether the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is within the reference concentration range by determining whether the film thickness reduction rate measured by the film thickness measuring unit 91 is within the reference speed range. Accordingly, it is possible to determine whether the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is within the reference concentration range while avoiding difficult measurements.

[0263] Since the amount of solvent evaporated in the first dissolution step and the final precipitation step is predictable, even when the concentration determination step is performed in the first precipitation step, it is possible to determine whether the thickness of the solid 121 of the sublimable substance formed on the upper surface of the substrate W is appropriate based on the concentration of the sublimable substance in the drying pretreatment liquid film 120 in the first precipitation step.

[0264] Therefore, when it is determined that the concentration of the sublimable substance in the pre-drying liquid film 120 is within the reference concentration range, after the final precipitation step is completed, a solid 121 of the sublimable substance with an appropriate thickness is formed. Therefore, as long as the substrate treatment is continued to sublime the solid 121 of the sublimable substance, the failure rate of the pattern PA on the upper surface of the substrate W can be reduced.

[0265] On the other hand, when it is determined that the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is not within the reference concentration range, before the solid 121 of the sublimable substance is precipitated, the sublimable substance can be removed from the upper surface of the substrate W by removing the liquid (pre-drying treatment liquid removal process). Accordingly, the situation in which the solid 121 of the sublimable substance of inappropriate thickness is formed on the upper surface of the substrate W can be prevented before it happens. Accordingly, the increase in the failure rate of the pattern PA can be suppressed. In addition, even when it is determined that the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is not within the reference concentration range, the pre-drying treatment liquid on the upper surface of the substrate W can be removed. Therefore, the substrate W can be reused.

[0266] In addition, in this embodiment, by comparing the reference data SD with the film thickness reduction rate measured in the first precipitation step, the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is estimated. Therefore, in the first precipitation step, the concentration of the sublimable substance in the pre-drying treatment liquid film 120 can be easily estimated.

[0267] In addition, in the present embodiment, when it is determined in the concentration determination step that the concentration of the sublimable substance in the drying pre-treatment liquid film 120 is not within the reference concentration range, the operator is notified of the abnormality (first abnormality notification step). Therefore, the operator can determine whether to continue the substrate processing at an appropriate time based on the notification of the abnormality.

[0268] In addition, in the present embodiment, just before the solid 121 of the sublimable substance is precipitated by evaporation of the solvent, the thickness of the pre-drying treatment liquid film 120 is measured by the film thickness measuring unit 91 (film thickness measuring step). Then, the controller 3 determines whether the thickness of the pre-drying treatment liquid film 120 measured in the film thickness measuring step is within the reference thickness range of the solid 121 of the sublimable substance (thickness determination step).

[0269] Therefore, by determining whether the thickness of the drying pre-treatment liquid film 120 when the concentration of the sublimable substance in the drying pre-treatment liquid film 120 reaches the saturation concentration of the sublimable substance is within the reference thickness range of the solid 121 of the sublimable substance, it is possible to determine whether the thickness of the solid 121 of the sublimable substance formed on the upper surface of the substrate W is appropriate.

[0270] When the thickness of the solid 121 of the sublimable substance formed on the upper surface of the substrate W is appropriate, the solid 121 of the sublimable substance with an appropriate thickness is formed after the final precipitation step. Therefore, as long as the substrate treatment is continued to sublime the solid 121 of the sublimable substance, the substrate W with a reduced failure rate of the pattern PA can be obtained.

[0271] On the other hand, when the thickness of the solid 121 of the sublimable substance formed on the upper surface of the substrate W is inappropriate, the occurrence of the substrate W with an increased failure rate of the pattern PA can be suppressed by interrupting the substrate processing.

[0272] In this embodiment, when it is determined in the thickness determination step that the film thickness measured in the film thickness measurement step is not within the above-mentioned reference thickness range, the operator is notified of the abnormality (second abnormality notification step). Therefore, the operator can determine whether to continue the substrate processing at an appropriate time based on the notification of the abnormality.

[0273] In the present embodiment, in the first precipitation step, the solvent is not evaporated from the drying pretreatment liquid by heating the drying pretreatment liquid, but the solvent is evaporated from the drying pretreatment liquid while the drying pretreatment liquid is maintained at a temperature below room temperature. In this case, the concentration of the sublimable substance locally increases on the surface of the drying pretreatment liquid, and the solid 121 of the sublimable substance is precipitated on the surface of the drying pretreatment liquid or in the vicinity thereof (room temperature precipitation step). At the same time, the drying pretreatment liquid remains between the solid 121 of the sublimable substance and the upper surface of the pattern PA. The solid 121 of the sublimable substance is dissolved in the drying pretreatment liquid.

[0274] In contrast, if the solvent is evaporated from the drying pretreatment liquid by heating the drying pretreatment liquid in the first precipitation step, the temperature of the drying pretreatment liquid rises to a value higher than room temperature, and the concentration of the sublimable substance in the drying pretreatment liquid rises. If the solid 121 of the sublimable substance is precipitated by natural cooling or forced cooling of the drying pretreatment liquid after the concentration of the sublimable substance is increased, there is a situation in which most or all of the main body of the drying pretreatment liquid becomes the solid 121 of the sublimable substance.

[0275] If the pre-drying treatment liquid does not remain above the pattern PA, the sublimable substance solid 121 will not be effectively dissolved in the pre-drying treatment liquid. Even if the pre-drying treatment liquid remains between the patterns PA, the efficiency of the sublimable substance solid 121 dissolving in the pre-drying treatment liquid between the patterns PA is inferior to the efficiency of the sublimable substance solid 121 dissolving in the main body of the pre-drying treatment liquid. Therefore, by maintaining a part of the main body of the pre-drying treatment liquid as liquid, the sublimable substance solid 121 can be effectively dissolved in the pre-drying treatment liquid.

[0276] In addition, in the present embodiment, in the first dissolution process, the drying pre-treatment liquid on the upper surface of the substrate W is heated, and the temperature of the drying pre-treatment liquid is raised to a value higher than the room temperature. The dissolution of the solid 121 of the sublimable substance in the drying pre-treatment liquid is promoted by the temperature rise of the drying pre-treatment liquid. Accordingly, the solid 121 of the sublimable substance can be effectively dissolved in the drying pre-treatment liquid. Furthermore, since the forced dissolution of the solid 121 of the sublimable substance begins with the start of heating, the forced dissolution of the solid 121 of the sublimable substance can be started at any period by changing the timing of starting heating.

[0277] In addition, in the present embodiment, in the first dissolution process, the solid 121 of the sublimable substance and the pre-drying treatment liquid are not directly heated from the top of the substrate W, but are indirectly heated across the substrate W (indirect heating process). If the solid 121 of the sublimable substance and the pre-drying treatment liquid are heated from the top of the substrate W, there is a situation where a part of the solid 121 of the sublimable substance located on the surface of the pre-drying treatment liquid sublimates. In this case, a part of the sublimable substance is wasted, and the thickness of the final solid 121 of the sublimable substance is less than the intended value. If the solid 121 of the sublimable substance and the pre-drying treatment liquid are heated across the substrate W, can the disappearance of such sublimable substance be reduced.

[0278] In addition, in the present embodiment, in the final precipitation process, in order to precipitate the solid 121 of the sublimable substance on the substrate W, the pre-drying treatment liquid is heated while the solvent is evaporated from the pre-drying treatment liquid. Accordingly, the solid 121 of the sublimable substance is precipitated from the high-temperature pre-drying treatment liquid. The saturation concentration of the sublimable substance in the pre-drying treatment liquid increases as the temperature of the pre-drying treatment liquid increases. The ratio of the solvent contained in the solid 121 of the sublimable substance decreases as the saturation concentration of the sublimable substance increases. When the solid 121 of the sublimable substance is sublimated, the solvent contained in the solid 121 of the sublimable substance may generate a destructive force that destroys the pattern PA. Therefore, by reducing the content of the solvent, the destructive rate of the pattern PA can be further reduced.

[0279] In addition, in the present embodiment, in the 1st precipitation process, the solid 121 of sublimable substance is precipitated on the surface of the dry pre-treatment liquid film 120 (liquid surface precipitation process). When the solvent evaporates from the dry pre-treatment liquid, the heat of the dry pre-treatment liquid equivalent to the heat of vaporization is released in the gas atmosphere together with the solvent, and the temperature of the surface of the dry pre-treatment liquid is reduced. When the solid 121 of sublimable substance is formed, the solvent evaporated from the dry pre-treatment liquid is reduced, and therefore, the heat of the dry pre-treatment liquid released in the gas atmosphere is also reduced. Meanwhile, the heat in the gas atmosphere is transferred to the dry pre-treatment liquid via the solid 121 of sublimable substance. Accordingly, the temperature of the interface of the solid 121 of sublimable substance and the dry pre-treatment liquid rises. Therefore, even if the dry pre-treatment liquid on the substrate W is not heated compulsorily, the solid 121 of sublimable substance can be dissolved in the dry pre-treatment liquid (natural dissolution process).

[0280] The film thickness monitoring process is not limited to Fig.15 For example, Fig.17 A flowchart showing the flow of the second example of the film thickness monitoring process is shown in FIG. Fig. 20 A flowchart showing the flow of the third example of the film thickness monitoring process is shown in FIG. Fig. 22A flowchart showing the flow of the fourth example of the film thickness monitoring process is shown in FIG.

[0281] exist Fig.17 The film thickness monitoring process of the second example shown in FIG. 1 is different from the film thickness monitoring process of the first example (see FIG. Fig.15 ) The different aspects are as follows: different processes are started when the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is higher than the upper limit of the reference concentration range, and when the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is lower than the lower limit of the reference concentration range.

[0282] In the film thickness monitoring process of the second example, when the film thickness reduction speed is greater than the upper limit value of the reference speed range or when the film thickness reduction speed is less than the lower limit value of the reference speed range (in Fig.17 In step S23, the result is No), the controller 3 makes the alarm device 100C (refer to Figure 8 ) generates an alarm (the first abnormality notification process, Fig.17 Then, the controller 3 determines whether the film thickness reduction speed is less than the lower limit value of the reference speed range ( Fig.17 Step S31).

[0283] When the film thickness reduction rate is less than the lower limit of the reference rate range (in Fig.17 In step S31, the result is yes), that is, when the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is higher than the upper limit of the reference concentration range, the controller 3 starts the solvent evaporation suppression step to suppress the evaporation of the solvent from the liquid film on the substrate W ( Fig.17 According to this, the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is reduced and adjusted to be within the reference concentration range.

[0284] On the other hand, when the film thickness reduction rate is greater than the upper limit of the reference rate range (in Fig.17 In step S31, the result is No), that is, when the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is lower than the lower limit of the reference concentration range, the controller 3 starts the solvent evaporation promotion step to promote the evaporation of the solvent from the pre-drying treatment liquid film 120 ( Fig.17 In step S33), the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is increased and adjusted to be within the reference concentration range.

[0285] After starting the solvent evaporation suppressing step or the solvent evaporation promoting step, Fig.15 Similarly, the controller 3 causes the film thickness measuring unit 91 to stop measuring the thickness of the pre-drying treatment liquid film 120 ( Fig.17 Step S26).

[0286] Fig.18 This is a schematic diagram for explaining an example of the solvent evaporation suppression step. In the solvent evaporation suppression step, for example, mist or vapor of the solvent is supplied to the space between the upper surface of the substrate W and the lower surface 51L of the shielding member 51 . Fig.18 2 shows an example in which the drying pretreatment liquid is a solution of camphor and IPA, and the space between the upper surface of the substrate W and the lower surface 51L of the shielding member 51 is filled with nitrogen gas containing mist or vapor of IPA. When the drying pretreatment liquid is a solution of camphor and methanol, nitrogen gas containing mist or vapor of methanol is sprayed toward the upper surface of the substrate W. The nitrogen gas is equivalent to a carrier gas that transports the mist or vapor of the solvent to the substrate W.

[0287] When spraying to the space between the upper surface of the substrate W and the lower surface 51L of the shielding member 51, it is sufficient to supply nitrogen gas to the IPA (liquid) in the tank (so-called bubbling). In this way, a plurality of nitrogen bubbles are formed in the IPA, and the nitrogen gas including the mist or vapor of the IPA is released from the surface of the IPA in the tank. It is sufficient to spray the nitrogen gas from at least one of the central nozzle 55 and the upper central opening 61 of the shielding member 51.

[0288] If the mist or vapor of the solvent is supplied to the space between the upper surface of the substrate W and the lower surface 51L of the blocking member 51, the vapor pressure of the solvent in the gas atmosphere in contact with the pre-drying treatment liquid film 120 rises. Therefore, the solvent is suppressed from evaporating from the pre-drying treatment liquid film 120. On the other hand, since the vapor pressure of the sublimation substance in the gas atmosphere is constant, the sublimation substance evaporates from the pre-drying treatment liquid, although it is a trace amount. Therefore, when it is assumed that the concentration of the sublimation substance is higher than the upper limit of the reference concentration range, as long as the mist or vapor of the solvent is supplied to the space between the upper surface of the substrate W and the lower surface 51L of the blocking member 51, the concentration of the sublimation substance in the pre-drying treatment liquid film 120 can be set to a concentration within the reference concentration range, and the solid 121 of the sublimation substance of the intended thickness can be precipitated.

[0289] Fig.19 1 is a schematic diagram for explaining an example of the solvent evaporation promotion process. In the solvent evaporation promotion process, a gas such as nitrogen that does not contain IPA mist or vapor is supplied to the space between the upper surface of the substrate W and the lower surface 51L of the blocking member 51. The controller 3 can make the central nozzle 55 spray nitrogen gas, or can make the upper central opening 61 of the blocking member 51 spray nitrogen gas. When the central nozzle 55 has sprayed nitrogen gas, the controller 3 can also increase the flow rate adjustment valve 58 (see Figure 2 When the upper central opening 61 of the blocking member 51 has already ejected nitrogen, the controller 3 may also increase the flow rate regulating valve 65 (refer to Figure 2 ) opening.

[0290] If nitrogen is supplied to the space between the upper surface of substrate W and the lower surface 51L of blocking member 51, the vapor pressure of the solvent in the gas atmosphere contacted with the dry pre-treatment liquid film 120 is reduced. Therefore, the solvent is promoted to evaporate from the dry pre-treatment liquid. Strictly speaking, the vapor pressure of the sublimation substance in the gas atmosphere is also a trace, but it reduces. However, because the vapor pressure of the sublimation substance is much smaller than the vapor pressure of the solvent, the solvent mainly evaporates from the dry pre-treatment liquid. Therefore, the concentration of the sublimation substance in the dry pre-treatment liquid film 120 can be set to the concentration within the reference concentration range, and the solid 121 of the sublimation substance of the intended thickness can be separated out.

[0291] The nitrogen gas ejected from the central nozzle 55 and the upper central opening 61 of the blocking member 51 promotes the precipitation of the solid 121 of the sublimable substance, so that the central nozzle 55 and the upper central opening 61 of the blocking member 51 function as a solvent evaporating unit.

[0292] By comparing the film thickness reduction rate immediately before the solvent evaporation suppression process or the solvent evaporation promotion process is performed with the film thickness reduction rate included in the reference data SD, it is possible to calculate the appropriate amount of evaporation of the solvent from the pre-drying treatment liquid film 120 in order to set the concentration of the sublimable substance in the pre-drying treatment liquid film 120 to a concentration within the reference concentration range. As long as the solvent evaporation suppression process or the solvent evaporation promotion process is performed in a manner such that the evaporation amount of the solvent becomes an appropriate evaporation amount, the thickness of the pre-drying treatment liquid film 120 when the concentration of the sublimable substance reaches the saturation concentration can be easily adjusted to an appropriate thickness. In addition, the solid 121 of the sublimable substance of an appropriate thickness can be precipitated.

[0293] In the second example of the film thickness monitoring process, when it is determined in the concentration determination process that the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is higher than the upper limit value of the reference concentration range, the evaporation of the solvent from the pre-drying treatment liquid film 120 is suppressed by supplying solvent vapor or mist to the gas atmosphere in contact with the pre-drying treatment liquid film 120 (solvent evaporation suppression process).

[0294] By supplying the vapor or mist of the solvent to the gas atmosphere in contact with the pre-drying treatment liquid film 120, the amount of the solvent (the vapor pressure of the solvent) present in the gas atmosphere in contact with the pre-drying treatment liquid film 120 increases. Accordingly, the evaporation of the solvent from the pre-drying treatment liquid film 120 can be suppressed. If the evaporation of the solvent from the pre-drying treatment liquid film 120 is suppressed, the ratio of the sublimable substance in the substance evaporated from the pre-drying treatment liquid film 120 increases. Therefore, the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is reduced. Accordingly, the concentration of the sublimable substance in the pre-drying treatment liquid film 120 can be adjusted to within the reference concentration range.

[0295] Therefore, even if the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is determined to be higher than the upper limit of the reference concentration range in the concentration determination step, since the solvent evaporation suppression step is performed, a substrate W with a reduced failure rate of the pattern PA can be obtained after the sublimation step.

[0296] In addition, in the second example of the film thickness monitoring process, when it is determined in the concentration determination process that the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is lower than the lower limit value of the reference concentration range, an inert gas is supplied to the gas atmosphere in contact with the pre-drying treatment liquid film 120 during the execution of the first precipitation process, thereby promoting the evaporation of the solvent from the pre-drying treatment liquid film 120 (solvent evaporation promotion process).

[0297] By promoting the evaporation of the solvent from the pre-drying treatment liquid film 120, the concentration of the sublimable substance in the pre-drying treatment liquid film 120 increases. Accordingly, the concentration of the sublimable substance in the pre-drying treatment liquid film 120 can be adjusted to be within the reference concentration range. Therefore, even if the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is determined to be lower than the lower limit of the reference concentration range in the concentration determination step, since the solvent evaporation promotion step is performed, after the sublimation step, a substrate W with a reduced failure rate of the pattern PA can be obtained.

[0298] exist Fig. 20 In the third example of the film thickness monitoring process shown in FIG. 1 , the thickness of the film is monitored by the second example (see FIG. Fig.17 ) is different in that: when the film thickness reduction rate is less than the lower limit of the reference rate range (in Fig. 20 In step S31, the answer is yes), that is, when the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is higher than the upper limit of the reference concentration range, the controller 3 starts the thin filming process to thin the pre-drying treatment liquid film 120 on the substrate W ( Fig. 20 Step S34).

[0299] When the film thickness reduction rate is greater than the upper limit of the reference speed range (in Fig. 20 In step S31 of , it is No), that is, when the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is lower than the lower limit of the reference concentration range, the controller 3 starts the solvent evaporation promotion process ( Fig. 20 Step S33).

[0300] In the thinning step, the controller 3 controls the rotary motor 14 to accelerate the rotation of the substrate W. This increases the centrifugal force acting on the pre-drying treatment liquid film 120 on the substrate W, and increases the amount of the pre-drying treatment liquid discharged to the outside of the substrate W.

[0301] Fig.21A and Fig.21B This is a schematic diagram for explaining the thin film forming process. Fig.21A represents the state before the rotation of the substrate W is accelerated, Fig.21B The state after accelerating the rotation of the substrate W is shown. Specifically, the rotation speed of the substrate W is changed from the first deposition speed (eg, 500 rpm) to a thin-filming speed (eg, 1500 rpm) that is higher than the first deposition speed.

[0302] When the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is higher than the upper limit of the reference concentration range, the thickness of the solid 121 of the sublimable substance before sublimation is greater than the intended value. If the thickness of the pre-drying treatment liquid film 120 on the substrate W is reduced, the amount of the sublimable substance contained in the pre-drying treatment liquid film 120 is reduced, and therefore, the thickness of the solid 121 of the sublimable substance is also reduced.

[0303] Therefore, in the third example of the film thickness monitoring process, when the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is higher than the upper limit of the reference concentration range, the rotation speed of the substrate W is increased to cause the centrifugal force to act on the pre-drying treatment liquid film 120, thereby reducing the thickness of the pre-drying treatment liquid film 120 before the solid 121 of the sublimable substance is precipitated. Accordingly, the thickness of the solid 121 of the sublimable substance formed on the upper surface of the substrate W can be reduced, and the solid 121 of the sublimable substance of the intended thickness can be precipitated. Therefore, even if the concentration of the sublimable substance in the pre-drying treatment liquid film 120 is determined to be higher than the upper limit of the reference concentration range in the concentration determination process, since the thin filming process is performed, after the sublimation process, the substrate W with a reduced failure rate of the pattern PA can be obtained.

[0304] When the pre-drying treatment liquid is a solution of camphor and IPA, Fig. 22 The fourth example of the film thickness monitoring process is similar to the first example of the film thickness monitoring process (see Fig.15 ) is different from the following aspects: when determining that the thickness of the solid 121 of the sublimable substance is within the reference thickness range (in Fig. 22 In step S25, if it is yes), the controller 3 starts the first dissolution process ( Fig. 22 That is, the controller 3 starts supplying a heating liquid such as warm water to the lower surface of the substrate W, and starts heating the liquid film of the drying pre-treatment liquid on the upper surface of the substrate W through the substrate W. Thereafter, the film thickness measuring unit 91 stops measuring the film thickness of the drying pre-treatment liquid ( Fig. 22 Step S26).

[0305] In the fourth example of the film thickness monitoring process, the first dissolution process is started with the formation of the solid 121 of the sublimable substance of appropriate thickness. Therefore, only when the solid 121 of the sublimable substance of appropriate thickness is formed, the first dissolution process, the final precipitation process and the sublimation process are performed. After the sublimation process is completed, the substrate W with a reduced failure rate of the pattern PA can be obtained. When the solid 121 of the sublimable substance of appropriate thickness is not formed, the processes after the first precipitation process (the first dissolution process, the final precipitation process and the sublimation process) can be omitted, and the substrate processing can be interrupted early.

[0306] When the time from the precipitation of the solid 121 of the sublimable substance to the sublimation is short, part or all of the solid 121 of the sublimable substance may sublime before the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid, in other words, before the heating of the pre-drying treatment liquid is started. In such a case, as long as the precipitation of the solid 121 of the sublimable substance is monitored, the heating of the pre-drying treatment liquid can be started at the optimal time, and the sublimable solid 121 of the sublimable substance that is sublimated unintentionally can be reduced.

[0307] The present invention is not limited to the contents of the above-described embodiment, and various modifications can be made.

[0308] As mentioned above, in the above-mentioned substrate processing, the film thickness monitoring process is performed together with the first precipitation process (step S7) at the beginning. However, when the drying pre-treatment liquid is a solution of camphor and IPA, the monitoring of the thickness of the drying pre-treatment liquid film can also be performed whenever the solid 121 of the sublimable substance is precipitated.

[0309] In addition, when the drying pretreatment liquid is a solution of camphor and IPA, the thickness of the drying pretreatment liquid film 120 can also be monitored as follows: Fig. 9 The two dotted lines in the middle are shown, which is different from the final precipitation process ( Fig. 9 In other words, when the pre-drying treatment liquid is a solution of camphor and IPA, as long as the first precipitation step ( Fig. 9 Step S7) and the final precipitation step ( Fig. 9 The thickness of the pre-drying treatment liquid film 120 may be monitored in parallel with at least one of the steps S9).

[0310] The substrate processing of the above embodiment (see Fig. 9 ) are different, such as Fig.23 As shown, a substrate treatment may be performed in which the solid 121 of the sublimable substance precipitated in the pre-drying treatment liquid film 120 is sublimated without being dissolved in the pre-drying treatment liquid.

[0311] exist Fig.23In the substrate processing of the embodiment, after the film thickness reduction process (step S6), a precipitation process (step S50) is performed to precipitate a solid of a sublimable substance on the upper surface of the substrate W, and thereafter, a sublimation process (step S10) is performed. Then, in parallel with the precipitation process (step S50), any one of the film thickness monitoring processes in the first to third examples is performed.

[0312] In the first precipitation step ( Fig. 9 In step S7), instead of maintaining the pre-drying treatment liquid film 120 at a temperature below room temperature, the solvent may be evaporated from the pre-drying treatment liquid on the substrate W while being heated at a heating temperature higher than room temperature.

[0313] In the final precipitation step ( Fig. 9 In step S9), the forced heating of the pre-drying treatment liquid on the substrate W may be stopped while the solvent is evaporated from the pre-drying treatment liquid, rather than heating the pre-drying treatment liquid on the substrate W while the solvent is evaporated from the pre-drying treatment liquid.

[0314] When the solid 121 of the sublimable substance is dissolved in the drying pretreatment liquid, a heating gas having a temperature higher than room temperature may be sprayed toward the upper surface or the lower surface of the substrate W, instead of supplying warm water, which is an example of a heating liquid having a temperature higher than room temperature, to the lower surface of the substrate W. For example, nitrogen gas having a temperature higher than room temperature may be sprayed from at least one of the central nozzle 55 and the lower central opening 81 of the rotating base 12. A heating element that generates Joule heat by energizing and a lamp that emits light toward the substrate W may be arranged at least one of the upper side and the lower side of the substrate W. For example, a heating element may be placed inside at least one of the rotating base 12 and the shielding member 51.

[0315] The sublimable solid 121 may also be removed by a processing unit 2 different from the wet processing unit 2w. The processing unit 2 for removing the sublimable solid 121 may be a part of the substrate processing apparatus 1, or may be a part of a substrate processing apparatus 1 different from the substrate processing apparatus 1. In other words, the substrate processing apparatus 1 having the wet processing unit 2w and the substrate processing apparatus 1 having the processing unit 2 for removing the sublimable solid 121 may be arranged in the same substrate processing system, and before removing the sublimable solid 121, the substrate W may be transported from the substrate processing apparatus 1 to another substrate processing apparatus 1.

[0316] When the rinsing liquid on the substrate W can be replaced with the pre-drying liquid, such as pure water, the pre-drying liquid supplying step may be performed instead of the replacement liquid supplying step of replacing the rinsing liquid on the substrate W with the replacement liquid.

[0317] The shielding member 51 may include a cylindrical portion extending downward from the outer circumference of the disk portion 52 in addition to the disk portion 52. In this case, when the shielding member 51 is disposed in the lower position, the substrate W held by the spin chuck 10 is surrounded by the cylindrical portion 25.

[0318] The blocking member 51 may also rotate around the rotation axis A1 together with the spin chuck 10. For example, the blocking member 51 may be placed on the rotating base 12 in a manner not to contact the substrate W. In this case, the blocking member 51 is connected to the rotating base 12, and therefore, the blocking member 51 rotates in the same direction and at the same speed as the rotating base 12.

[0319] The blocking member 51 may be omitted. However, when a liquid such as pure water is supplied to the lower surface of the substrate W, it is preferable to provide the blocking member 51. The reason for this is that the blocking member 51 can be used to block droplets flowing from the lower surface of the substrate W along the outer peripheral surface of the substrate W to the upper surface of the substrate W and droplets splashing inward from the processing cup 21, thereby reducing the amount of liquid mixed into the drying pre-processing liquid on the substrate W.

[0320] If there is no need to change the incident position of the light from the light emitting element 92 with respect to the upper surface of the substrate W, the electric motor 96 of the film thickness measuring unit 91 may be omitted.

[0321] When the light of the light emitting element 92 is made incident substantially vertically on the upper surface of the substrate W, the housing 93 of the film thickness measuring unit 91 may accommodate a light receiving element 97 in addition to the light emitting element 92. In this case, the light of the light emitting element 92 (reflected light) reflected by the upper surface of the substrate W passes through the opening of the housing 93 covered by the transparent plate 94, and is received by the light receiving element 97 in the housing 93.

[0322] When both the light emitting element 92 and the light receiving element 97 are accommodated in the housing 93, the controller 3 may also move the housing 93 horizontally to move the incident position of the light of the light emitting element 92 on the upper surface of the substrate W in the radial direction of the substrate W. Specifically, a scanning arm that holds the housing 93 above the substrate W held by the rotary chuck 10 and an electric driver that moves the scanning arm horizontally in the chamber 4 may be provided in the processing unit 2.

[0323] In the above embodiment, the film thickness measuring unit 91 cannot measure the liquid film of the drying pretreatment liquid after the solid 121 of the sublimable substance is precipitated. Unlike the above embodiment, a film thickness measuring unit 191 capable of measuring the thickness of the solid 121 of the sublimable substance may be used as the film thickness measuring unit (see Fig.25A). The film thickness measuring unit 191 accommodates the light emitting element 191A and the light receiving element 191B in the same housing 191C. The film thickness measuring unit 191 can be moved, for example, along the rotational radial direction of the substrate W by the moving unit 192. Specifically, a scanning arm that holds the housing 191C above the substrate W held by the rotating chuck 10 and an electric drive that moves the scanning arm horizontally in the chamber 4 can also be provided in the processing unit 2.

[0324] Therefore, the film thickness measurement unit 191 can measure the thickness of the solid 121 (solid film) of the sublimable substance precipitated on the upper surface of the substrate W at a plurality of locations on the upper surface of the substrate W while moving above the substrate W. Fig.25A The multiple black dots Pi in ⊥ represent the incident positions of the light from the light emitting element 191A onto the upper surface of the substrate W.

[0325] As long as the film thickness measuring unit 191 is configured to be able to perform measurements at a plurality of locations on the upper surface of the substrate W, the Fig.24 The fifth example of the film thickness monitoring process is shown. Fig.24 The fifth example of the film thickness monitoring process shown in FIG. Fig.15 The different aspects of the first example of the film thickness monitoring process shown are as follows: performing a flatness measuring process to measure the flatness of the surface of the solid 121 of the sublimable substance on the upper surface of the substrate W; and a flatness judging process to judge whether the surface of the solid 121 of the sublimable substance is flat.

[0326] Specifically, when the thickness of the solid 121 of the sublimable substance is appropriate (in Fig.24 In step S25, if it is YES), the film thickness measuring unit 191 starts to move in the rotation radial direction of the substrate W ( Fig.24 Step S51). Accordingly, Fig.25A As shown, the flatness of the surface of the solid 121 of the sublimable substance is measured (flatness measuring step).

[0327] The flatness refers to, for example, the degree of unevenness of the height position of the surface of the solid 121 of the sublimable substance measured at multiple locations. The height position of the surface of the solid 121 of the sublimable substance can be directly measured by the film thickness measuring unit 191, or can be calculated from the thickness of the solid 121 of the sublimable substance measured by the film thickness measuring unit 191. The smaller the unevenness of the height position of the surface of the solid 121 of the sublimable substance measured at multiple locations, the flatter the surface of the solid 121 of the sublimable substance.

[0328] Furthermore, it is determined whether the surface of the solid 121 of the sublimable substance is sufficiently flat (flatness determination step, Fig.24In step S52), it is possible to check whether the solid 121 of the sublimable substance is formed with a uniform thickness in the entire area of ​​the upper surface of the substrate W.

[0329] Specifically, when the flatness measured in the flatness measuring step is within the reference flatness range (in Fig.24 In step S52, if it is Yes), that is, when the surface of the solid 121 of the sublimable substance is sufficiently flat, the measurement of the thickness of the pre-drying treatment liquid film 120 by the film thickness measuring unit 191 is stopped ( Fig.24 Thereafter, the sublimation process is performed as usual ( Fig. 9 Step S10). Therefore, it is possible to obtain a substrate W having a reduced failure rate of the pattern PA.

[0330] If the flatness measured in the flatness measurement step is not within the reference flatness range (in Fig.24 In step S52, the result is No), that is, when the surface of the solid 121 of the sublimable substance is not flat enough, the solid 121 of the sublimable substance is removed from the upper surface of the substrate W (solid removal step, Fig.24 In the solid removal process, as in step S53. Fig.25B As shown, a solvent corresponding to the replacement liquid is supplied from the replacement liquid nozzle 43 to the upper surface of the substrate W on which the solid 121 of the sublimable substance is formed.

[0331] Fig.25B The example in which the pre-drying treatment liquid is a solution of camphor and IPA and the solvent is IPA is shown. In the case where the pre-drying treatment liquid is a solution of camphor and methanol, methanol is ejected from the replacement liquid nozzle 43 instead of IPA. Fig.25C As shown, the solid 121 of the sublimable substance is removed. Thereafter, the thickness measurement of the pre-drying treatment liquid film 120 by the film thickness measurement unit 191 is stopped ( Fig.24 Step S26).

[0332] In the film thickness monitoring process of the fifth example, the solid removal process is performed, so even if there is a part of the solid 121 of the sublimable substance that is too thin or too thick, the pattern PA can be prevented from being damaged. In addition, since the solid 121 of the sublimable substance on the upper surface of the substrate W is removed, the substrate W can be reused.

[0333] Thus, when the pre-drying treatment liquid is a solution of camphor and IPA, in the solid removal process, IPA plays a role as a solid removal liquid for removing the solid 121 of the sublimable substance from the upper surface of the substrate W. When the pre-drying treatment liquid is a solution of camphor and methanol, in the solid removal process, methanol plays a role as a solid removal liquid. The solid removal liquid is preferably a liquid of the same type as the solvent used in the pre-drying treatment liquid, but is not limited thereto. The solid removal liquid may also be a liquid of a different type from the solvent of the pre-drying treatment liquid as long as it can remove the solid 121 of the sublimable substance.

[0334] The substrate processing apparatus 1 is disposed in a clean room, and the temperature in the substrate processing apparatus 1 is maintained at the same or substantially the same value as the temperature in the clean room, but the temperature in the substrate processing apparatus 1 may be different from the temperature in the clean room. For example, the substrate processing apparatus 1 may also include an air conditioner for adjusting the temperature in the substrate processing apparatus 1.

[0335] In the case where the drying pretreatment liquid is a solution of camphor and methanol, if the temperature in the substrate processing device 1, more specifically the temperature in the chamber 4, is higher than the surface temperature of the drying pretreatment liquid when the sublimable substance is precipitated (hereinafter referred to as "precipitation surface temperature"), the drying pretreatment liquid is only placed on the upper surface of the substrate W, and the temperature of the interface between the solid 121 of the sublimable substance and the drying pretreatment liquid rises, and the solid 121 of the sublimable substance is dissolved in the drying pretreatment liquid. Accordingly, the precipitation and dissolution of the sublimable substance are naturally repeated.

[0336] When the temperature in the clean room is lower than the surface temperature during precipitation, the controller 3 may control the air conditioner to adjust the temperature in the substrate processing apparatus 1 so that the internal space of the chamber 4 is maintained at a temperature higher than the surface temperature during precipitation. Similarly, when the air pressure in the clean room is a value that is not suitable for the precipitation and dissolution of the sublimable substance, the controller 3 may change the FFU 6 (see Figure 2 ) output and exhaust valve 9 (refer to Figure 2 In this case, at least one of the flow rate of the gas supplied to the chamber 4 and the flow rate of the gas discharged from the chamber 4 changes, and the gas pressure in the chamber 4 is maintained at a value suitable for the precipitation and dissolution of the sublimable substance.

[0337] The substrate processing apparatus 1 may also include at least one of a thermometer for measuring the temperature in the chamber 4 and a barometer for measuring the air pressure in the chamber 4. When at least one of the temperature and the air pressure in the chamber 4 changes significantly during the processing of the substrate W by the processing unit 2, the controller 3 may also stop the next substrate W from being carried into the chamber 4 until both the temperature and the air pressure in the chamber 4 are maintained at values ​​suitable for the precipitation and dissolution of the sublimable substance.

[0338] The substrate processing apparatus 1 is not limited to an apparatus for processing a disc-shaped substrate W, and may be an apparatus for processing a polygonal substrate W.

[0339] Although the embodiments of the present invention have been described in detail, these are merely specific examples for clarifying the technical content of the present invention, and the present invention should not be construed as being limited to these specific examples. The scope of the present invention is limited only by the appended claims.

[0340] This application corresponds to Japanese Patent Application No. 2018-248018 filed with the Japan Patent Office on December 28, 2018, and all disclosed contents of the application are incorporated herein by reference.

[0341] Explanation of symbols

[0342] 1: Substrate processing equipment

[0343] 3: Controller

[0344] 10: Rotating chuck

[0345] 14: Rotary motor (solvent evaporation unit, sublimation unit)

[0346] 39: Drying pre-treatment liquid nozzle (drying pre-treatment liquid supply unit)

[0347] 55: Central nozzle (solvent evaporation unit, sublimation unit)

[0348] 61: Upper central opening of the blocking member (solvent evaporation unit, sublimation unit)

[0349] 71: Lower surface nozzle (solvent evaporation unit)

[0350] 91: Film thickness measurement unit

[0351] 120: Drying pre-treatment liquid film (drying pre-treatment liquid night film)

[0352] 121: Solids of sublimable substances

[0353] 191: Film thickness measurement unit

[0354] PA: Pattern

[0355] W: substrate.

Claims

1. A substrate processing method, comprising: A pre-drying treatment liquid supply step of supplying a pre-drying treatment liquid, which is a solution obtained by dissolving a sublimable substance in a solvent, to the upper surface of a patterned substrate, and forming a liquid film of the pre-drying treatment liquid on the upper surface of the substrate; A precipitation step of precipitating a solid of the sublimable substance on the upper surface of the substrate by evaporating the solvent from the liquid film; A film thickness reduction rate measurement step of measuring a film thickness reduction rate, which is a rate at which the thickness of the liquid film is reduced by evaporation of the solvent, before the solid of the sublimable substance precipitates in the precipitation step; A reduction rate determination step of determining whether the film thickness reduction rate measured in the film thickness reduction rate measurement step is within a reference rate range; and A sublimation step of sublimating the solid of the sublimable substance after the precipitation step when it is determined in the reduction rate determination step that the film thickness reduction rate is within the reference concentration range.

2. The substrate processing method according to claim 1, wherein the reference rate range is determined based on a reference concentration range and reference data. The reference concentration range represents a concentration range of the sublimable substance in the liquid film when the film thickness reduction rate becomes within the reference rate range, and the reference data is reference data prepared by pre-measuring the film thickness reduction rate for each liquid film of pre-drying treatment liquids having different concentrations of the sublimable substance.

3. A substrate processing method, comprising: A pre-drying treatment liquid supply step of supplying a pre-drying treatment liquid, which is a solution obtained by dissolving a sublimable substance in a solvent, to the upper surface of a patterned substrate, and forming a liquid film of the pre-drying treatment liquid on the upper surface of the substrate; A precipitation step of precipitating a solid of the sublimable substance on the upper surface of the substrate by evaporating the solvent from the liquid film; A film thickness measurement step of measuring the thickness of the liquid film before the solid of the sublimable substance precipitates by evaporation of the solvent in the precipitation step; A thickness determination step of determining whether the thickness of the liquid film measured in the film thickness measurement step is within a reference thickness range of the solid of the sublimable substance; and A sublimation step of sublimating the solid of the sublimable substance after the precipitation step when it is determined in the thickness determination step that the thickness of the liquid film measured in the film thickness measurement step is within the reference thickness range.

4. The substrate processing method according to claim 3, further comprising an abnormality notification step of notifying an abnormality when it is determined in the thickness determination step that the thickness of the liquid film is not within the reference thickness range.

5. The substrate processing method according to claim 3 or 4, further comprising: Flatness measurement step, which is performed when the thickness of the liquid film in the precipitation step is determined to be within the reference thickness range in the thickness determination step, by measuring the height positions of the surfaces of the solid of the sublimable substance at multiple locations on the upper surface of the substrate, thereby measuring the flatness of the surface of the solid of the sublimable substance; Flatness determination step, which determines whether the flatness measured in the flatness measurement step is within the reference flatness range, The sublimation step, which is performed after the precipitation step when it is determined in the flatness determination step that the flatness measured in the flatness measurement step is within the reference flatness range.

6. The substrate processing method according to claim 5, further comprising a solid removal step, which is performed when it is determined in the flatness determination step that the flatness is not within the reference flatness range, by supplying a removal liquid to the upper surface of the substrate, thereby removing the solid of the sublimable substance from the upper surface of the substrate.

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