Substrate drying method and substrate processing apparatus

Abstract

A drying pretreatment liquid, which is a solution containing a sublimable substance and a solvent, is supplied to the upper surface of a substrate. Then, by evaporating the solvent from the drying pretreatment liquid on the substrate, a solid of a sublimable substance is precipitated in the drying pretreatment liquid on the substrate. Then, at least a portion of the solid of the sublimable substance is dissolved in the pre-drying treatment liquid on the substrate. Then, the solid of the sublimable substance is precipitated on the substrate by evaporating the solvent from the pre-drying treatment liquid in which the solid of the sublimable substance is dissolved. Then, by sublimating the solid of the sublimable substance, the solid of the sublimable substance is removed from the upper surface of the substrate.

Description

[0001] This application is a divisional application of an application with a filing date of November 11, 2019, application number 2019110956620, and invention name “Substrate drying method and substrate processing device”. Technical Field

[0002] This application claims the benefit of Japanese Patent Application No. 2018-211715 filed on November 9, 2018, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a substrate drying method and a substrate processing device for drying substrates. The substrates include, for example, semiconductor wafers, liquid crystal display devices and organic EL (electroluminescence) display devices, FPD (Flat Panel Display) substrates, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, photomask substrates, ceramic substrates, solar cell substrates, etc. Background Art

[0004] In the manufacturing process of semiconductor devices and FPDs, 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 to dry the substrate. In a single-wafer substrate processing device that processes substrates one by one, spin drying is performed, that is, the substrate is dried by removing the liquid on the substrate by utilizing the high-speed rotation of the substrate.

[0005] In the case where a pattern is formed on the surface of the substrate, when the substrate is dried, the force caused by the surface tension of the processing liquid attached to the substrate is applied to the pattern, causing the pattern to collapse. As a countermeasure, a liquid with a small surface tension such as IPA (isopropyl alcohol) is supplied to the substrate, or a hydrophobic agent whose contact angle with the pattern is close to 90 degrees is supplied to the substrate. However, even if IPA or a hydrophobic agent is used, the collapse force that causes the pattern to collapse will not be zero, so it varies depending on the pattern strength, and even if these countermeasures are adopted, there may be a situation where the pattern collapse cannot be fully prevented.

[0006] Recently, as a technology to prevent pattern collapse, sublimation drying has received attention. For example, Japanese JP2012-243869A discloses a substrate drying method and a substrate processing device for sublimation drying. In the sublimation drying described in Japanese JP2012-243869A, a solution of a sublimation substance is supplied to the upper surface of the substrate, and the DIW on the substrate is replaced with a solution of the sublimation substance. Then, the solvent of the sublimation substance is evaporated to separate out the sublimation substance. Thus, a film consisting of a solid sublimation substance is formed on the upper surface of the substrate. Then, the substrate is heated. Thus, the sublimation substance on the substrate sublimates and is removed from the substrate.

[0007] Generally, sublimation drying has a lower pattern collapse rate than conventional drying methods such as spin drying in which liquid is removed by high-speed rotation of the substrate and IPA drying using IPA. However, if the pattern strength is extremely low, even if sublimation drying is performed, it may not be possible to fully prevent pattern collapse. Summary of the invention

[0008] One embodiment of the present invention provides a substrate drying method, which includes: a drying pretreatment liquid supplying step, supplying a drying pretreatment liquid to the upper surface of a substrate formed with a pattern, and forming a liquid film of the drying pretreatment liquid on the upper surface of the substrate, wherein the drying pretreatment liquid is a solution containing a sublimable substance corresponding to a solute and a solvent in which the sublimable substance is dissolved; a first precipitation step, evaporating the solvent from the drying pretreatment liquid on the upper surface of the substrate, thereby precipitating a solid of the sublimable substance from the drying pretreatment liquid on the upper surface of the substrate; a first dissolving step, dissolving at least a portion of the solid of the sublimable substance in the drying pretreatment liquid on the upper surface of the substrate; a final precipitation step, evaporating the solvent from the drying pretreatment liquid in which the solid of the sublimable substance is dissolved, thereby precipitating the solid of the sublimable substance on the upper surface of the substrate; and a sublimation step, removing the solid of the sublimable substance from the upper surface of the substrate by sublimating the solid of the sublimable substance.

[0009] According to this method, a solution of a sublimable substance and a solvent equivalent to the drying pre-treatment liquid is supplied to the upper surface of the substrate. Thus, a liquid film of the drying pre-treatment liquid is formed on the upper surface of the substrate. Then, the solvent is evaporated from the drying pre-treatment liquid. The concentration of the sublimable substance in the drying pre-treatment liquid rises 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 precipitated in the drying pre-treatment liquid.

[0010] When the solid of the sublimable substance begins to precipitate, the upper surface of the substrate has the drying pre-treatment liquid remaining. At least a part of the solid of the sublimable substance is dissolved in the drying pre-treatment liquid. Then, the solvent is evaporated from the drying pre-treatment liquid again. Thus, the amount of the solvent is reduced, and the solid of the sublimable substance is precipitated on the upper surface of the substrate. Then, the solid of the sublimable substance is sublimated and removed from the substrate. In this way, the drying pre-treatment liquid is removed from the substrate, and the substrate is dried.

[0011] Before the solid of the sublimable substance is initially precipitated, the pre-drying treatment liquid exists not only between the patterns but also above the patterns. The spacing between the patterns on substrates such as semiconductor wafers or FPD substrates is narrow. If the spacing between the patterns is narrow, the pre-drying treatment liquid between the patterns has different properties from the matrix of the pre-drying treatment liquid, that is, the pre-drying treatment liquid between the patterns has different properties from the pre-drying treatment liquid located in the range from the surface (upper surface) of the pre-drying treatment liquid to the upper surface of the pattern. The difference in properties between the two becomes significant as the spacing between the patterns becomes narrower.

[0012] If the interval of pattern is narrow, then when the solid of sublimable substance is separated out at first, there will be the situation that the solid of sublimable substance is separated out only in the matrix of drying pre-treatment liquid, and the incomplete precipitation area of ​​solid of sublimable substance does not exist or hardly exists between the patterns formed in the upper surface of substrate. In this case, the surface tension of drying pre-treatment liquid between patterns is applied to the side of pattern, so, when the solid of sublimable substance is sublimated, the pattern in the incomplete precipitation area will collapse. This becomes the reason of rising (deterioration) of pattern collapse rate.

[0013] On the other hand, if the solid of the sublimable substance separated out is dissolved in the dry pre-treatment liquid, the solid of the sublimable substance is separated out again, even if the narrow space such as the space between the patterns can also form the crystal nucleus of the solid of the sublimable substance. Therefore, if the solid of the sublimable substance separated out is dissolved in the dry pre-treatment liquid, the solid of the sublimable substance is separated out again, even if the interval of the pattern is narrow, it is possible to prevent the occurrence of incomplete separation region or reduce its area. Thus, the collapse of the pattern can be reduced and the collapse rate of the pattern can be reduced.

[0014] In the embodiment, at least one of the following features may be added to the substrate drying method.

[0015] The first precipitation step includes: a room temperature precipitation step, by maintaining the pre-drying treatment liquid on the upper surface of the substrate at a temperature less than or equal to room temperature, and evaporating the solvent from the pre-drying treatment liquid on the upper surface of the substrate, thereby precipitating the solid of the sublimable substance in the pre-drying treatment liquid on the upper surface of the substrate.

[0016] According to this method, the solvent is not evaporated from the drying pre-treatment liquid by heating the drying pre-treatment liquid, but the drying pre-treatment liquid is maintained at a temperature less than or equal to room temperature, and the solvent is evaporated from the drying pre-treatment liquid. In this case, the concentration of the sublimable substance locally rises on the surface of the drying pre-treatment liquid, and the solid of the sublimable substance is precipitated on the surface of the drying pre-treatment liquid or near it. At the same time, the drying pre-treatment liquid remains between the solid of the sublimable substance and the upper surface of the pattern. The solid of the sublimable substance dissolves in the drying pre-treatment liquid.

[0017] In contrast, if the solvent is evaporated from the drying pretreatment liquid by heating the drying pretreatment liquid, 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. After the concentration of the sublimable substance is raised, if the solid of the sublimable substance is precipitated by naturally cooling or forced cooling the drying pretreatment liquid, most or all of the matrix of the drying pretreatment liquid may be changed into the solid of the sublimable substance.

[0018] If the pre-drying treatment liquid does not remain above the pattern, the solid of the sublimable substance will not be efficiently dissolved in the pre-drying treatment liquid. Even if the pre-drying treatment liquid remains between the patterns, the efficiency of the solid of the sublimable substance dissolving in the pre-drying treatment liquid between the patterns is not as good as the efficiency of the solid of the sublimable substance dissolving in the matrix of the pre-drying treatment liquid. Therefore, by maintaining a part of the matrix of the pre-drying treatment liquid as liquid, the solid of the sublimable substance can be efficiently dissolved in the pre-drying treatment liquid.

[0019] The first dissolving step includes a heating step of heating the pre-drying treatment liquid on the upper surface of the substrate at a heating temperature higher than room temperature.

[0020] According to this method, the drying pre-treatment liquid on the upper surface of the heating substrate is dried, and the temperature of the drying pre-treatment liquid is raised to a value higher than room temperature. The solid of the sublimable substance can be promoted to dissolve to the drying pre-treatment liquid by the temperature rise of the drying pre-treatment liquid. Thus, the solid of the sublimable substance can be dissolved in the drying pre-treatment liquid efficiently. And, because along with the start of heating, the solid of the sublimable substance is forced to dissolve, so, by changing the opportunity of starting heating, the solid of the sublimable substance can be forced to dissolve at any period.

[0021] The heating step includes an indirect heating step of heating the substrate from below the substrate to heat the pre-drying treatment liquid on the upper surface of the substrate at the heating temperature.

[0022] According to the method, not directly heat the solid and dry pre-treatment liquid of sublimation material from the top of substrate, but indirectly heat the solid and dry pre-treatment liquid of sublimation material via substrate.If heat the solid and dry pre-treatment liquid of sublimation material from the top of substrate, then there will be the situation of a part of sublimation of the solid of the sublimation material on the surface of dry pre-treatment liquid.In this case, not only the part of sublimation material is wasted, and the thickness of the solid of final sublimation material is also less than expected value.If heat the solid and dry pre-treatment liquid of sublimation material via substrate, then can reduce the loss of this sublimation material.

[0023] The final precipitation step includes a step of precipitating a solid of the sublimable substance on the upper surface of the substrate by heating the pre-drying treatment liquid on the upper surface of the substrate at the heating temperature and evaporating the solvent from the pre-drying treatment liquid on the upper surface of the substrate.

[0024] According to this method, in order to separate out the solid of sublimable substance on substrate, heat and dry pre-treatment liquid, and make solvent evaporate from the dry pre-treatment liquid.Thus, the solid of sublimable substance separates out from the high temperature dry pre-treatment liquid.The saturation concentration of sublimable substance in the dry pre-treatment liquid rises along with the temperature rise of the dry pre-treatment liquid.The ratio of the solid solvent of sublimable substance reduces along with the rising of the saturation concentration of sublimable substance.When making the solid of sublimable substance sublimate, the solid solvent of sublimable substance can produce the collapse force that makes pattern collapse.Therefore, by reducing the content of solvent, the collapse rate of pattern can be further reduced.

[0025] The first precipitation process includes: a liquid surface precipitation process, in which the solvent is evaporated from the pre-drying treatment liquid on the upper surface of the substrate, thereby precipitating the solid of the sublimable substance on the surface of the pre-drying treatment liquid on the upper surface of the substrate; the first dissolution process includes: a natural dissolution process, in which the temperature of the pre-drying treatment liquid is increased by the heat of the ambient gas in contact with the solid of the sublimable substance, or the temperature of the pre-drying treatment liquid is increased by utilizing the heat of the ambient gas in contact with the solid of the sublimable substance, so that at least a portion of the solid of the sublimable substance is dissolved in the pre-drying treatment liquid on the upper surface of the substrate, or at least a portion of the solid of the sublimable substance is dissolved.

[0026] According to the method, separate out the solid of sublimable substance on the surface of dry pre-treatment liquid.When solvent evaporates from dry pre-treatment liquid, the heat of dry pre-treatment liquid equivalent to heat of vaporization is released into the ambient gas together with solvent, and the temperature on the surface of dry pre-treatment liquid reduces.If form the solid of sublimable substance, then the solvent evaporated from dry pre-treatment liquid reduces, so, the heat of dry pre-treatment liquid released into the ambient gas also reduces.Meanwhile, the heat in the ambient gas is transferred to dry pre-treatment liquid via the solid of sublimable substance.Thus, the temperature of the interface between the solid of sublimable substance and dry pre-treatment liquid rises.Therefore, even if the dry pre-treatment liquid on the substrate is not forced to heat, the solid of sublimable substance can be dissolved in dry pre-treatment liquid.

[0027] Another embodiment of the present invention provides a substrate processing device, which comprises: a drying pre-treatment liquid supply unit, which supplies a drying pre-treatment liquid to the upper surface of a substrate formed with a pattern and forms a liquid film of the drying pre-treatment liquid on the upper surface of the substrate, wherein the drying pre-treatment liquid is a solution containing a sublimable substance corresponding to a solute and a solvent in which the sublimable substance is dissolved; a first precipitation unit, which evaporates the solvent from the drying pre-treatment liquid on the upper surface of the substrate, thereby precipitating a solid of the sublimable substance from the drying pre-treatment liquid on the upper surface of the substrate; a first dissolving unit, which dissolves at least a part of the solid of the sublimable substance in the drying pre-treatment liquid on the upper surface of the substrate; a final precipitation unit, which evaporates the solvent from the drying pre-treatment liquid in which the solid of the sublimable substance is dissolved, thereby precipitating the solid of the sublimable substance on the upper surface of the substrate; and a sublimation unit, which removes the solid of the sublimable substance from the upper surface of the substrate by sublimating the solid of the sublimable substance. According to this structure, the same effect as the above-mentioned substrate drying method can be achieved.

[0028] The above and other objects, features and effects of the present invention will become apparent from the following description of the embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1A This is a schematic diagram of a substrate processing apparatus according to an embodiment of the present invention as viewed from above.

[0030] Figure 1B This is a schematic diagram of a substrate processing apparatus viewed from the side.

[0031] Figure 2 It is a schematic diagram showing the interior of a processing unit included in the substrate processing apparatus when viewed horizontally.

[0032] Figure 3 This is a schematic diagram of the horizontal observation film thickness measurement unit, the rotation chuck, and the shielding member.

[0033] Figure 4 This is a schematic diagram of the film thickness measurement unit and the rotation chuck viewed from above.

[0034] Figure 5 It is a cross-sectional view showing the interior of a housing in which a light emitting element is housed.

[0035] Figure 6 is along Figure 5 A cross-sectional view along line VI-VI is shown.

[0036] Figure 7 It is a schematic diagram showing a pre-drying processing liquid supply unit provided in the substrate processing apparatus.

[0037] Figure 8 This is a block diagram showing the hardware of the control device.

[0038] Fig. 9 The present invention is a process diagram for explaining processing of a substrate using a substrate processing apparatus.

[0039] Fig. 10A This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0040] Fig. 10B This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0041] Fig. 10C This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0042] Fig. 10D This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0043] Fig.10E This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0044] Fig.10F This is a schematic diagram showing the state of a substrate when a solution of camphor and IPA is used.

[0045] Fig.11 This is the equilibrium diagram of camphor and IPA.

[0046] Fig. 12A This is a schematic diagram showing the state of a substrate when a solution of camphor and methanol is used.

[0047] Fig. 12B This is a schematic diagram showing the state of a substrate when a solution of camphor and methanol is used.

[0048] Fig. 12C This is a schematic diagram showing the state of a substrate when a solution of camphor and methanol is used.

[0049] Fig.12D This is a schematic diagram showing the state of a substrate when a solution of camphor and methanol is used.

[0050] Fig.13 It is a graph showing the pattern collapse rate.

[0051] Fig.14 : is a graph showing the change with time of the thickness of the liquid film of the pre-drying treatment liquid on the upper surface of the substrate W until the solid of the sublimable substance is precipitated from the pre-drying treatment liquid.

[0052] Fig.15This is a flow chart showing the flow from the start of measuring the film thickness of the pre-drying treatment liquid to the solid precipitation of the sublimable substance.

[0053] Fig.16A This is a schematic diagram for explaining an example of an exception handling process.

[0054] Fig. 16B This is a schematic diagram for explaining another example of the abnormality handling process.

[0055] Fig. 16C This is a schematic diagram for explaining another example of the abnormality handling process.

[0056] Fig.17 This is a flowchart showing a detailed flow from the start of the first precipitation step to the start of the first dissolution step when the drying pretreatment liquid is a solution of camphor and IPA. DETAILED DESCRIPTION

[0057] 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, one atmosphere or a value close to it).

[0058] Figure 1A This is a schematic diagram of a substrate processing apparatus according to an embodiment of the present invention as viewed from above. Figure 1B This is a schematic diagram of a substrate processing apparatus viewed from the side.

[0059] like Figure 1A As shown, the substrate processing device 1 is a single-chip device that processes circular plate-shaped substrates W such as semiconductor wafers one by one. The substrate processing device 1 comprises: a loading platform LP, which holds a carrier CA containing substrates W; a plurality of processing units 2, which process substrates W transported from the carrier CA on the loading platform LP with a processing fluid such as a processing liquid or a processing gas; a transport robot, which transports substrates W between the carrier CA on the loading platform LP and the processing unit 2; and a control device 3, which controls the substrate processing device 1.

[0060] The transport robot includes: an indexing robot IR, which carries substrates W into and out of the carrier CA on the loading platform LP; and a central robot CR, which carries substrates W into and out of the plurality of processing units 2. The indexing robot IR carries substrates W between the loading platform 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 an arm H1 for supporting the substrate W, and the indexing robot IR includes an arm H2 for supporting the substrate W.

[0061] In a plan view, the plurality of processing units 2 form a plurality of towers TW arranged around the central robot CR. Figure 1AThis shows an example of forming four towers TW. The central robot CR can access any tower TW. Figure 1B As shown, each tower TW includes a plurality of (eg, three) processing units 2 stacked one above the other.

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

[0063] 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 horizontally holds a substrate W in the chamber 4 and rotates the substrate W around a vertical rotation axis A1 passing through the center of the substrate W, and a cylindrical processing cup 21 that surrounds the rotation axis A1 and surrounds the spin chuck 10.

[0064] The chamber 4 includes: a box-shaped partition wall 5 provided with a loading and unloading port 5b for the substrate W to pass through, and a gate plate 7 for opening and closing the loading and unloading port 5b. The FFU6 (fan filter unit) is arranged above the air supply port 5a provided on the upper part of the partition wall 5. The FFU6 usually supplies clean air (air filtered by a filter) into the chamber 4 from the air supply port 5a. The gas in the chamber 4 is discharged from the chamber 4 through the exhaust duct 8 connected to the bottom of the processing cup 21. As a result, a downward airflow of clean air is usually formed in the chamber 4. The flow rate of the exhaust gas discharged to the exhaust duct 8 changes with the opening of the exhaust valve 9 arranged in the exhaust duct 8.

[0065] The spin chuck 10 includes: a disk-shaped spin base 12, which is held in a horizontal position; a plurality of chuck pins 11, which hold the substrate W in a horizontal position above the spin base 12; a rotation shaft 13, which extends downward from the center of the spin base 12; and a rotation motor 14, which 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 also be a vacuum chuck in which the substrate W is held horizontally by adsorbing the back side (lower surface) of the substrate W, which is a non-device forming surface, with the upper surface 12u of the spin base 12.

[0066] The processing cup 21 includes: a plurality of baffles 24 for receiving the processing liquid discharged from the substrate W to the outside; a plurality of cups 23 for receiving the processing liquid guided downward by the plurality of baffles 24; and a cylindrical outer wall member 22 surrounding the plurality of baffles 24 and the plurality of cups 23. Figure 2 An example is shown in which four baffles 24 and three cups 23 are provided, and the outermost cup 23 is formed integrally with the third baffle 24 from the top.

[0067] The baffle 24 includes: a cylindrical portion 25, which surrounds the rotating chuck 10; and an annular top portion 26, which is inclined from the upper end of the cylindrical portion 25 toward the rotation axis A1 and extends upward. A plurality of top portions 26 overlap each other, and a plurality of cylindrical portions 25 are arranged in a concentric circle. From a top view, the annular upper end of the top portion 26 corresponds to the upper end 24u of the baffle 24 surrounding the substrate W and the rotating base 12. A plurality of cups 23 are respectively arranged below the plurality of cylindrical portions 25. The cup 23 is formed with an annular liquid receiving tank for receiving the processing liquid guided downward by the baffle 24.

[0068] The processing unit 2 includes a baffle lifting unit 27 for lifting and lowering each of the plurality of baffles 24. The baffle lifting unit 27 allows the baffles 24 to be located at any position from an upper position to a lower position. Figure 2 The diagram shows a state where two baffles 24 are arranged at the upper position and the remaining two baffles 24 are arranged at the lower position. The upper position is when the upper end 24u of the baffle 24 is arranged at a position above the holding position where the substrate W held by the spin chuck 10 is arranged. The lower position is when the upper end 24u of the baffle 24 is arranged at a position below the holding position.

[0069] When supplying the processing liquid to the rotating substrate W, at least one baffle 24 is arranged in the upper position. In this state, the processing liquid is supplied to the substrate W, and 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 baffle 24 facing the substrate W horizontally, and is guided to the cup 23 corresponding to the baffle 24. Thus, the processing liquid discharged from the substrate W is collected in the processing cup 21.

[0070] The processing unit 2 includes a plurality of nozzles for spraying a processing liquid toward the substrate W held by the spin chuck 10. The plurality of nozzles include: a chemical liquid nozzle 31 for spraying a chemical liquid toward the upper surface of the substrate W; a rinse liquid nozzle 35 for spraying a rinse liquid toward the upper surface of the substrate W; a drying pre-processing liquid nozzle 39 for spraying a drying pre-processing liquid toward the upper surface of the substrate W; and a replacement liquid nozzle 43 for spraying a replacement liquid toward the upper surface of the substrate W.

[0071] The chemical liquid nozzle 31 may be a scanning nozzle that can move horizontally in the chamber 4, or may be a fixed nozzle that is fixed to the partition wall 5 of the chamber 4. The rinse liquid nozzle 35, the pre-drying liquid nozzle 39, and the replacement liquid nozzle 43 are provided in the same manner. 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, respectively, is shown.

[0072] The liquid medicine nozzle 31 is connected to a liquid medicine pipe 32 for guiding the liquid medicine to the liquid medicine nozzle 31. When the liquid medicine valve 33 installed on the liquid medicine pipe 32 is opened, the liquid medicine is continuously sprayed downward from the spray port of the liquid medicine nozzle 31. The liquid medicine sprayed from the liquid medicine nozzle 31 may be a liquid including at least one of sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid, phosphoric acid, acetic acid, ammonia water, hydrogen peroxide solution, organic acid (e.g., citric acid, oxalic acid, etc.), organic base (e.g., TMAH: tetramethylammonium hydroxide, etc.), surfactant and corrosion inhibitor, or other liquids.

[0073] Although not shown in the figure, the liquid medicine valve 33 includes: a valve body, which is provided with an annular valve seat for liquid medicine to pass through; a valve core, which can move relative to the valve seat; an actuator, which moves the valve core between a closed position and an open position, wherein the closed position is a position where the valve core contacts the valve seat, and the open position is a position where the valve core is away from the valve seat. The same arrangement is applied to other valves. The actuator can be a pneumatic actuator or an electric actuator, or an actuator other than these. The control device 3 opens and closes the liquid medicine valve 33 by controlling the actuator.

[0074] 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.

[0075] 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 on 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 can be any one of carbonated water, electrolytic ion water, hydrogen-rich water, ozone water, and hydrochloric acid water of a diluted concentration (for example, about 10 to 100 ppm).

[0076] 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 ejected 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.

[0077] The drying pre-treatment liquid nozzle 39 is connected to a drying pre-treatment liquid piping 40 that guides the treatment liquid to the drying pre-treatment liquid nozzle 39. When a drying pre-treatment liquid valve 41 installed on the drying pre-treatment liquid piping 40 is opened, the drying pre-treatment liquid is continuously ejected downward from the ejection port of the drying pre-treatment 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 on the replacement liquid piping 44 is opened, the replacement liquid is continuously ejected downward from the ejection port of the replacement liquid nozzle 43.

[0078] The pre-drying treatment liquid is a solution including a sublimable substance equivalent to a solute and a solvent that is compatible with the sublimable substance. The sublimable substance can be a substance that changes from a solid to a gas directly without passing through a liquid at normal temperature (same as room temperature) or normal pressure (pressure in the substrate processing device 1, such as one atmosphere or a value close thereto).

[0079] The freezing point of the drying pretreatment liquid (freezing point under one atmosphere of pressure. The same applies hereinafter) is lower than room temperature (for example, 23°C or a value close thereto). The substrate processing apparatus 1 is arranged in a clean room maintained at room temperature. Therefore, even if the drying pretreatment liquid is 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 is higher than the boiling point of the solvent. The vapor pressure of the solvent is higher than the vapor pressure of the sublimable substance.

[0080] The sublimable substance may be, for example, alcohols such as 2-methyl-2-propanol (also known as tert-butanol, t-butanol) or cyclohexanol, fluorinated hydrocarbon compounds, 1,3,5-trioxane (also known as metaformaldehyde), camphor (also known as camphor, camphor), dinaphthyl and iodine, or any other substance.

[0081] The solvent may be, for example, at least one selected from 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.

[0082] Next, an example in which the sublimable substance is camphor and the solvent is IPA or methanol will be described.

[0083] The freezing point of camphor is 175-177°C. The solvent is either IPA or methanol, and 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 evaporate more easily 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 smaller than that of water. The molecular weight of methanol is smaller than that of IPA.

[0084] As described later, a replacement liquid is supplied to the upper surface of the substrate W covered by the liquid film of the rinse liquid, and a drying pre-treatment liquid is supplied to the upper surface of the substrate W covered by the liquid film of the replacement liquid. The replacement liquid can be any liquid that can be miscible with both the rinse liquid and the drying pre-treatment liquid. The replacement liquid is, for example, IPA (liquid). The replacement liquid can be a mixture of IPA and HFE, or a liquid other than these. The replacement liquid can be a liquid with the same name as a component of the drying pre-treatment liquid such as a solvent, or a liquid with a name different from any component of the drying pre-treatment liquid.

[0085] When a 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 efficiently replaced with the replacement liquid. For the same reason, the replacement liquid on the substrate W can be efficiently replaced with the drying pre-treatment liquid. As a result, the rinsing liquid contained in the drying pre-treatment liquid on the substrate W can be reduced.

[0086] 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.

[0087] 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, which is a 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, which is a position where the replacement liquid nozzle 43 is located around the processing cup 21 in a plan view.

[0088] The processing unit 2 includes a shielding member 51 disposed above the spin chuck 10 . Figure 2 An example in which the shielding member 51 is a disk-shaped shielding plate is shown. The shielding member 51 includes a disk portion 52 horizontally arranged above the rotating chuck 10. The shielding 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 shielding member 51. The lower surface 51L of the shielding member 51 is an opposite surface relative to the upper surface of the substrate W. The lower surface 51L of the shielding member 51 is parallel to the upper surface of the substrate W and has an outer diameter greater than or equal to the diameter of the substrate W.

[0089] The shielding member 51 is connected to a shielding member lifting unit 54 that vertically lifts and lowers the shielding member 51. The shielding member lifting unit 54 positions the shielding member 51 from the upper position ( Figure 2 The lower position is a position where the lower surface 51L of the shielding member 51 approaches the upper surface of the substrate W to a height where the scanning nozzles such as the liquid medicine nozzle 31 cannot enter between the substrate W and the shielding member 51. The upper position is a spacing position where the shielding member 51 retreats to a height where the scanning nozzles can enter between the shielding member 51 and the substrate W.

[0090] The plurality of nozzles include a central nozzle 55, which sprays a processing fluid such as a processing liquid or a processing gas downward through an upper central opening 61 opened in the central portion of the lower surface 51L of the shielding 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 shielding member 51 from top to bottom. The inner circumferential surface of the shielding member 51 surrounds the outer circumferential surface of the central nozzle 55 at intervals in the radial direction (in a direction perpendicular to the rotation axis A1). The central nozzle 55 rises and falls together with the shielding member 51. The nozzle of the central nozzle 55 that sprays the processing fluid is arranged above the upper central opening 61 of the shielding member 51.

[0091] 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 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 on 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 degree 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 may be a gas other than nitrogen such as helium or argon.

[0092] The inner circumferential surface of the shielding member 51 and the outer circumferential surface of the central 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 guides the inert gas to the upper central opening 61 of the shielding member 51. The substrate processing device 1 may be provided with an upper temperature regulator 66 that heats or cools the inert gas ejected from the upper central opening 61 of the shielding member 51. When the upper gas valve 64 installed on the upper gas pipe 63 is opened, the inert gas is continuously ejected downward from the upper central opening 61 of the shielding 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 shielding member 51 is nitrogen. The inert gas may be a gas other than nitrogen such as helium or argon.

[0093] The plurality of nozzles include a lower surface nozzle 71 that sprays a processing liquid toward the center of the lower surface of the substrate W. The lower surface nozzle 71 includes: a nozzle disk portion that 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 that extends downward from the nozzle disk portion. The spray port of the lower surface nozzle 71 is opened 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.

[0094] The lower surface nozzle 71 is connected to a heating fluid piping 72, and the heating fluid piping 72 guides warm water (pure water with 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 the 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 the flow rate adjustment valve 74 that changes the flow rate of the warm water. In this way, warm water is supplied to the lower surface of the substrate W.

[0095] The lower surface nozzle 71 is also connected to a cooling fluid piping 76, which guides cold water (pure water below 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, 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 cold water. Thus, cold water is supplied to the lower surface of the substrate W.

[0096] 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 opened in the central part of the upper surface 12u of the rotating base 12. The lower gas flow path 82 is connected to a lower gas pipe 83 that guides the inert gas to the lower central opening 81 of the rotating base 12. The substrate processing device 1 may be provided with a lower temperature regulator 86 that heats or cools the inert gas ejected from the lower central opening 81 of the rotating base 12. When the lower gas valve 84 installed on 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 that changes the flow rate of the inert gas.

[0097] The inert gas ejected from the lower central opening 81 of the spin base 12 is nitrogen. The inert gas may be a gas other than nitrogen, such as helium or argon. When the spin chuck 10 holds the substrate W, if nitrogen is ejected from the lower central opening 81 of the spin base 12, the nitrogen flows radially in all directions between the lower surface of the substrate W and the upper surface 12u of the spin base 12. As a result, the space between the substrate W and the spin base 12 is filled with nitrogen.

[0098] Next, the film thickness measuring unit 91 will be described.

[0099] Figure 3 It is a schematic diagram of horizontally observing the film thickness measurement unit 91 , the spin chuck 10 , and the shielding member 51 . Figure 4 This 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 the housing 93 in which the light emitting element 92 is accommodated. Figure 6 is along Figure 5 A cross-sectional view along line VI-VI is shown.

[0100] like Figure 3 and Figure 4 As shown, the substrate processing device 1 has a film thickness measuring unit 91 for measuring the thickness (film thickness) of a liquid film located on the upper surface of the substrate W. The film thickness measuring unit 91 measures the film thickness by, for example, spectral interferometry. The film thickness measuring unit 91 includes: a light emitting element 92 for emitting light toward the upper surface of the substrate W held by the spin chuck 10; and a light receiving element 97 for receiving the light of the light emitting element 92 reflected by the upper surface of the substrate W. From a plan view, the light emitting element 92 and the light receiving element 97 are arranged at a position that does not overlap with the spin chuck 10 and the shielding member 51.

[0101] 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 closed 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 closed 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 .

[0102] like Figure 5 and Figure 6 As shown in FIG. 1 , the film thickness measuring unit 91 includes: a frame 95 for holding the light emitting element 92 in a housing 93; and an electric motor 96 for moving the frame 95 relative to the housing 93. The frame 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 a rotating shaft 96b of the electric motor 96 protrudes from an end surface of the motor housing 96a toward the axial direction of the electric motor 96. The rotating shaft 96b is connected to the frame 95, and the motor housing 96a is connected to the housing 93.

[0103] The rotation angle of the electric motor 96 is controlled by the control device 3. When the electric motor 96 rotates the rotation shaft 96b, the holder 95 together with the light emitting element 92 rotates relative to the housing 93 around the horizontal rotation axis A2. Figure 5 The white arrow in shows that the light emitting element 92 rotates around the rotation axis A2. As a result, 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.

[0104] If the incident position and the incident angle change, the path through which the reflected light of the 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 an element that can be moved in the following manner, that is, it 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 may be provided for the housing 98. 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 can be received by the light receiving element 97, and the thickness of the liquid film on the substrate W can be measured.

[0105] When measuring the thickness of the liquid film on the substrate W, the control device 3 may cause the spin chuck 10 to rotate the substrate W and place the incident position at a constant distance in the horizontal direction from the rotation axis A1, or may cause the incident position to move in the radial direction (horizontal direction perpendicular to the rotation axis A1) of the substrate W. In the latter case, the average value of a plurality of measured values ​​may be processed as the film thickness.

[0106] Next, the pre-drying treatment liquid supply unit 101 will be described.

[0107] Figure 7 1 is a schematic diagram showing a pre-drying treatment liquid supply unit 101 included in the substrate treatment apparatus 1 .

[0108] The substrate processing apparatus 1 includes a drying pre-processing liquid supply unit 101, which supplies the drying pre-processing liquid to the drying pre-processing liquid nozzle 39 through the drying pre-processing liquid pipe 40. The drying pre-processing liquid supply unit 101 includes a first tank 102A, which is equivalent to a stock liquid tank storing a stock liquid of the drying pre-processing liquid, and a second tank 102B, which is equivalent to a solvent tank storing a solvent of the drying pre-processing liquid.

[0109] The stock solution of the pre-drying treatment liquid includes a sublimable substance and a solvent. The stock solution of the pre-drying treatment liquid has a higher concentration of the sublimable substance than the pre-drying treatment liquid supplied to the substrate W. The stock solution of the pre-drying treatment liquid is supplied to the substrate W after being diluted by the solvent supplied from the second tank 102B. In the case where the sublimable substance is liquid at room temperature, the stock solution of the pre-drying treatment liquid may not contain a solvent.

[0110] The pre-drying treatment liquid supply unit 101 includes: a first circulation pipe 103A for circulating the stock solution in the first tank 102A; a first pump 104A for conveying the stock solution in the first tank 102A to the first circulation pipe 103A; and a first independent pipe 105A for guiding the stock solution in the first circulation pipe 103A to the pre-drying treatment liquid pipe 40. The pre-drying treatment liquid supply unit 101 also includes: a first opening and closing valve 106A for opening and closing the interior of the first independent pipe 105A; and a first flow regulating valve 107A for changing the flow rate of the pre-drying treatment liquid supplied from the first independent pipe 105A to the pre-drying treatment liquid pipe 40.

[0111] Similarly, the drying pre-treatment liquid supply unit 101 includes: a second circulation pipe 103B for circulating the solvent in the second tank 102B; a second pump 104B for conveying the solvent in the second tank 102B to the second circulation pipe 103B; a second independent pipe 105B for guiding the solvent in the second circulation pipe 103B to the drying pre-treatment liquid pipe 40. The drying pre-treatment liquid supply unit 101 also includes: a second opening and closing valve 106B for opening and closing the interior of the second independent pipe 105B; and a second flow regulating valve 107B for changing the flow rate of the drying pre-treatment liquid supplied from the second independent pipe 105B to the drying pre-treatment liquid pipe 40.

[0112] The first independent pipe 105A and the second independent pipe 105B are connected to the drying pre-treatment liquid pipe 40 through a mixing valve 108, and the mixing valve 108 generates the drying pre-treatment liquid by mixing the original liquid of the drying pre-treatment liquid and the solvent. The drying pre-treatment liquid pipe 40 is not only equipped with a drying pre-treatment liquid valve 41, but also equipped with a pipeline mixer 109. The pipeline 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.

[0113] The stock solution of the drying pre-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 drying pre-treatment liquid supplied to the drying pre-treatment liquid nozzle 39 can be changed.

[0114] The pre-drying liquid supply unit 101 includes a concentration meter 110 for measuring the concentration of the pre-drying liquid supplied from the pre-drying liquid nozzle 39. The pre-drying liquid supply unit 101 includes a measurement pipe 111 branched from the pre-drying liquid pipe 40. The concentration meter 110 is attached to the measurement pipe 111. Figure 7 The example in which the measurement piping 111 is connected to the pre-drying treatment liquid piping 40 at a position downstream of the line mixer 109 is shown. Therefore, in this example, the concentration of the pre-drying treatment liquid passing through both the mixing valve 108 and the line mixer 109 is measured using the concentration meter 110. The concentration meter 110 can be installed not only on the measurement piping 111 but also on the pre-drying treatment liquid piping 40.

[0115] Figure 8 It is a block diagram showing the hardware of the control device 3 .

[0116] The control device 3 is a computer, which includes a computer body 3a and peripheral devices 3d connected to the computer body 3a. The computer body 3a includes a CPU 3b (central processing unit) that executes various commands and a main storage device 3c that stores information. The peripheral devices 3d include an auxiliary storage device 3e that stores information such as a program P, a reading device 3f that reads information from a removable medium RM, and a communication device 3g that communicates with other devices such as a host computer.

[0117] The control device 3 is connected to the input device 100A, the display device 100B and the alarm device 100C. The user or the operator such as the maintenance person in charge operates the input device 100A to input information to 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, an indicating device and a touch panel, or a device other than these. A touch panel display that serves as both the input device 100A and the display device 100B can be provided on the substrate processing device 1. The alarm device 100C uses one or more of light, sound, characters and graphics to issue an alarm. If the input device 100A is a touch panel display, the input device 100A can also serve as the alarm device 100C.

[0118] 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 pre-installed in the control device 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 host computer via the communication device 3g.

[0119] The auxiliary storage device 3e and the removable medium RM are non-volatile memories that can 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 storage medium that records the program P. The removable medium RM is a non-temporary tangible storage medium.

[0120] The auxiliary storage device 3e stores a plurality of process specifications. The process specifications are information that specifies the processing content, processing conditions, and processing sequence of the substrate W. The plurality of process specifications differ from each other in at least one of the processing content, processing conditions, and processing sequence of the substrate W. The control device 3 controls the substrate processing device 1 in a manner that processes the substrate W according to the process specifications specified by the host computer. The substrate processing device 1 is controlled by the control device 3 to perform the following processes. In other words, the control device 3 is programmed to perform the following processes.

[0121] Next, an example of processing of the substrate W will be described.

[0122] 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 forming surface on which devices such as transistors or capacitors are formed. The substrate W may be a device forming surface, i.e., a surface of the substrate W on which a pattern PA is formed (see Fig. 10A ) or may be a substrate W without a pattern PA formed on the surface of the substrate W. In the latter case, the pattern PA may not be formed in the chemical solution supplying step described later.

[0123] First treatment example

[0124] First, an example (first processing example) of processing of the substrate W when the drying pre-processing liquid is a solution of camphor and IPA will be described.

[0125] Fig. 9 The flowchart is for explaining processing of the substrate W by the substrate processing apparatus 1 . Figures 10A to 10F FIG. 1 is a 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 table means room temperature. Figure 2 and Fig. 9 , appropriate reference Figures 10A to 10F and Fig.11 .

[0126] When the substrate W is processed by the substrate processing apparatus 1, a loading step ( Fig. 9 Step S1).

[0127] Specifically, the shielding member 51 is in the upper position, all the baffles 24 are in the lower position, and all the scanning nozzles are in the standby position. In this state, the central robot CR (see FIG. 1 ) supports the substrate W with the arm H1 and causes the arm H1 to enter the chamber 4. Then, the central robot CR places the substrate W on the arm H1 on the plurality of chuck pins 11 with the surface of the substrate W facing upward. Subsequently, the plurality of chuck pins 11 push the outer peripheral surface of the substrate W to hold the substrate W. After the central robot CR places the substrate W on the rotary chuck 10, it causes the arm H1 to withdraw from the interior of the chamber 4.

[0128] Next, the upper gas valve 64 and the lower gas valve 84 are opened, and nitrogen begins to be ejected from the upper central opening 61 of the shielding member 51 and the lower central opening 81 of the spin base 12. As a result, the space between the substrate W and the shielding member 51 is filled with nitrogen. Similarly, the space between the substrate W and the spin base 12 is also filled with nitrogen. On the other hand, the baffle lifting unit 27 raises at least one baffle 24 from the lower position to the upper position. Then, the rotation motor 14 is driven, and the substrate W begins to rotate ( Fig. 9Step S2). Thus, the substrate W is rotated at the liquid supply speed.

[0129] Next, the drug solution supply process is performed ( Fig. 9 In step S3), a chemical liquid is supplied to the upper surface of the substrate W to form a chemical liquid film covering the entire upper surface of the substrate W.

[0130] Specifically, when the shielding member 51 is in the upper position and at least one baffle plate 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. Then, the liquid medicine valve 33 is opened, and the liquid medicine nozzle 31 starts to spray the liquid medicine. After 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. Then, the nozzle moving unit 34 moves the liquid medicine nozzle 31 to the standby position.

[0131] The chemical liquid ejected from the chemical liquid nozzle 31 collides with the upper surface of the substrate W rotating at the 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 chemical liquid film covering the entire upper surface of the substrate W. When the chemical liquid nozzle 31 ejects the chemical liquid, the nozzle moving unit 34 can move the landing position of the chemical liquid relative to the upper surface of the substrate W so that the landing position passes through the central part and the peripheral part, or can keep the landing position stationary at the central part.

[0132] Next, the rinse liquid supply process is performed ( Fig. 9 In step S4), pure water as an example of a rinse liquid is supplied to the upper surface of the substrate W to rinse the chemical solution on the substrate W.

[0133] Specifically, when the shielding member 51 is in the upper position and at least one baffle plate 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. Then, the rinse liquid valve 37 is opened, and the rinse liquid nozzle 35 starts to spray the rinse liquid. Before starting to spray pure water, in order to switch the baffle plate 24 that receives the liquid discharged from the substrate W, the baffle plate lifting unit 27 can vertically move at least one baffle plate 24. After 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. Then, the nozzle moving unit 38 moves the rinse liquid nozzle 35 to the standby position.

[0134] After the pure water ejected from the rinse liquid nozzle 35 collides with the upper surface of the substrate W rotating at the liquid supply speed, it flows outward along the upper surface of the substrate W due to centrifugal force. The liquid on the substrate W is replaced by the pure water ejected from the rinse liquid nozzle 35. Thus, a pure water liquid film 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 landing position of the pure water relative to the upper surface of the substrate W in such a manner that the landing position passes through the central part and the peripheral part, or the landing position can be kept stationary at the central part.

[0135] Next, the replacement fluid supply step ( Fig. 9 In step S5), a replacement liquid mixed with 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.

[0136] Specifically, when the shielding member 51 is in the upper position and at least one baffle plate 24 is in the upper position, the nozzle moving unit 46 moves the replacement liquid nozzle 43 from the standby position to the processing position. Then, the replacement liquid valve 45 is opened, and the replacement liquid nozzle 43 starts to spray the replacement liquid. Before starting to spray the replacement liquid, in order to switch the baffle plate 24 that receives the liquid discharged from the substrate W, the baffle plate lifting unit 27 can vertically move at least one baffle plate 24. After a predetermined time has passed after the replacement liquid valve 45 is opened, the replacement liquid valve 45 is closed to stop spraying the replacement liquid. Then, the nozzle moving unit 46 moves the replacement liquid nozzle 43 to the standby position.

[0137] After the replacement liquid ejected from the replacement liquid nozzle 43 collides with the upper surface of the substrate W rotating at the 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. Thus, a replacement liquid film covering the entire 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 landing position of the replacement liquid relative to the upper surface of the substrate W through the central part and the peripheral part, or can make the landing position stationary in the central part. In addition, after the replacement liquid film covering the entire upper surface of the substrate W is formed, the replacement liquid nozzle 43 can stop ejecting the replacement liquid, and the substrate W can be rotated at an immersion speed (for example, a speed greater than 0 and less than or equal to 20rpm).

[0138] Next, the drying pre-treatment liquid supply process is performed ( Fig. 9 In step S6), the drying pre-treatment liquid is supplied to the upper surface of the substrate W to form a liquid film of the drying pre-treatment liquid on the substrate W.

[0139] Specifically, when the shielding member 51 is in the upper position and at least one baffle plate 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. Then, 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. Before starting to spray the drying pre-processing liquid, in order to switch the baffle plate 24 that receives the liquid discharged from the substrate W, the baffle plate lifting unit 27 can vertically move at least one baffle plate 24. After 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. Then, the nozzle moving unit 42 moves the drying pre-processing liquid nozzle 39 to the standby position.

[0140] 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 the liquid supply speed, it flows outward along the upper surface of the substrate W due to centrifugal force. The replacement liquid on the substrate W is replaced by the drying pre-treatment liquid ejected from the drying pre-treatment liquid nozzle 39. Thus, a liquid film of the drying pre-treatment liquid covering the entire upper surface of the substrate W is formed. When the drying pre-treatment liquid nozzle 39 ejects the drying pre-treatment liquid, the nozzle moving unit 42 can move the landing position of the drying pre-treatment liquid relative to the upper surface of the substrate W in such a manner that the landing position passes through the central part and the peripheral part, or the landing position can be kept stationary at the central part.

[0141] Next, a film thickness reduction step is performed ( Fig. 9 In step S7), the entire upper surface of the substrate W is maintained to be covered by the liquid film of the drying pre-treatment liquid, and the film thickness of the drying pre-treatment liquid on the substrate W (the thickness of the liquid film) is reduced.

[0142] Specifically, the shielding member lifting unit 54 moves the shielding member 51 from the upper position to the lower position. Subsequently, when the shielding member 51 is in the lower position and at least one baffle 24 is in the upper position, the rotary motor 14 maintains the rotation speed of the substrate W at the film thickness reduction speed. The film thickness reduction speed may be equal to or different from the liquid supply speed. After the spraying of the drying pre-treatment liquid is stopped, the drying pre-treatment liquid on the substrate W is also discharged from the substrate W to the outside by centrifugal force. Thus, the film thickness of the drying pre-treatment liquid on the substrate W is reduced. If 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. Thus, the film thickness of the drying pre-treatment liquid on the substrate W is stabilized to a value corresponding to the rotation speed of the substrate W.

[0143] In the film thickness reduction process ( Fig. 9 After the film thickness of the drying pre-treatment liquid is reduced in step S7), the first precipitation step ( Fig. 9 Step S8), the solid 121 (see Fig. 10B ) is precipitated from the drying pre-treatment liquid on the substrate W.

[0144] Specifically, when the shielding member 51 is in the lower position and at least one baffle 24 is in the upper position, the rotary motor 14 maintains the rotation speed of the substrate W at the first precipitation speed. The first precipitation speed may be equal to the liquid supply speed or may be different therefrom. Since the vapor pressure of the solvent is higher than the vapor pressure of the sublimable 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 sublimable substance. Fig. 10A The state where the solvent evaporates from the surface of the pre-drying treatment liquid is shown.

[0145] If the solvent continues to evaporate, the film thickness of the pre-drying treatment liquid gradually decreases, and the concentration of the sublimable substance on the surface of the pre-drying treatment liquid and its vicinity gradually increases. For example, the solvent from the pre-drying treatment liquid can be evaporated without forcibly heating the pre-drying treatment liquid on the substrate W. Therefore, the solvent is evaporated from the pre-drying treatment liquid while the pre-drying treatment liquid on the substrate W is maintained at room temperature or a temperature slightly lower than room temperature. Fig. 10B As shown, when the concentration of the sublimable substance on the surface of the pre-drying treatment liquid and its vicinity reaches the saturation concentration of the sublimable substance in the pre-drying treatment liquid, a solid 121 of the sublimable substance is precipitated on the surface of the pre-drying treatment liquid.

[0146] Fig. 10B As shown, if the solid 121 of the sublimable substance precipitates, the matrix of the drying pretreatment liquid, that is, the drying pretreatment liquid in the range from the surface (liquid surface) of the drying pretreatment liquid to the upper surface of the pattern PA, is completely or partially changed into the solid 121 of the sublimable substance. Fig. 10B The example in which only the pre-treatment liquid on the surface side of the pre-treatment liquid is changed into the solid 121 of the sublimable substance in the matrix of the pre-treatment liquid is shown, and the remaining matrix remains as liquid. In this example, the solid 121 of the sublimable substance does not reach the upper surface of the pattern PA, and the pre-treatment 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-treatment liquid is covered by the horizontally distributed film-like solid 121 of the sublimable substance, i.e., the solid film.

[0147] Next, the first dissolution step ( Fig. 9 In step S9), the solid 121 of the sublimable substance is dissolved in the drying pre-treatment liquid on the substrate W.

[0148] Specifically, when the shielding member 51 is in the lower position and at least one baffle 24 is in the upper position, the rotary motor 14 maintains the rotation speed of the substrate W at the first dissolution speed. The first dissolution speed may be equal to the liquid supply speed or may be different therefrom. Furthermore, the heating fluid valve 73 is opened, and the lower surface nozzle 71 starts to spray warm water (pure water above room temperature). Before starting to spray warm water, in order to switch the baffle 24 that receives the liquid discharged from the substrate W, the baffle lifting unit 27 may vertically move at least one baffle 24.

[0149] 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. Thus, the entire substrate W is heated at a heating temperature higher than room temperature. The heat of the warm water is transmitted to the drying pre-treatment liquid on the substrate W through the substrate W. The drying pre-treatment liquid on the substrate W is indirectly heated through the substrate W. Thus, the temperature of the sublimable substance solid 121 and the drying pre-treatment liquid on the substrate W is maintained at a temperature higher than room temperature.

[0150] like Fig. 10C As shown in FIG. 1 , if the temperature of the drying pre-treatment liquid on the substrate W is increased, the saturation concentration of the sublimable substance in the drying pre-treatment liquid increases, and the solid 121 of the sublimable substance is dissolved in the drying pre-treatment liquid on the substrate W. The dissolution of the solid 121 of the sublimable substance into the drying pre-treatment liquid is promoted by the increase in the temperature of the drying pre-treatment liquid. As a result, all or most of the solid 121 of the sublimable substance is dissolved in the drying pre-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.

[0151] After the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid, the solid 121 of the sublimable substance can be precipitated again, and the precipitated solid 121 of the sublimable substance can be dissolved in the pre-drying treatment liquid again. Fig. 9 Step S8) starts from the first dissolution step ( Fig. 9 A repetitive cycle up to step S9) can be performed twice or more ( Fig. 9 Step S10). Fig. 9 In step S10, "N" is an integer greater than 0. When N is greater than 1, the process is repeated twice or more. When N is 0, only the first precipitation step ( Fig. 9 Step S8) and the first dissolution step ( Fig. 9 Step S9), after two times, no precipitation and dissolution are performed.

[0152] After the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid, the final precipitation step ( Fig. 9 In step S11), the solid 121 of the sublimable substance is precipitated again.

[0153] Specifically, when the shielding member 51 is in the lower position and at least one baffle 24 is in the upper position, the rotary motor 14 maintains the rotation speed of the substrate W at the final precipitation speed. The final precipitation speed may be equal to the liquid supply speed or may be different from it. Fig. 9In step S9), warm water is continuously ejected from the lower surface nozzle 71. Therefore, the drying pre-treatment liquid on the substrate W is maintained at a temperature higher than room temperature while the substrate W is rotating at the final deposition speed.

[0154] like Fig. 10D As shown in FIG. 1 , 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. Therefore, the surface of the drying pre-treatment liquid gradually approaches the bottom of the pattern PA, and the concentration of the sublimable substance in the drying pre-treatment liquid gradually increases. If the concentration of the sublimable substance in the drying pre-treatment liquid reaches the saturation concentration of the sublimable substance in the drying pre-treatment liquid, a 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. Fig.10E An example is shown in which all the pre-drying treatment liquid disappears and a solid 121 of a 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.

[0155] 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) shows the freezing point of a solution of camphor and IPA. Fig.11 The bold line in the figure shows the first precipitation step ( Fig. 9 Step S8), the first dissolution step ( Fig. 9 Step S9) and the final precipitation step ( Fig. 9 The concentration of camphor and the change of solution temperature during step S11).

[0156] exist Fig.11 In the example, the thick straight line from point P1 to point P2 indicates that the first precipitation step ( Fig. 9 Step S8). When performing 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. If the concentration of camphor rises to Fig.11 At the concentration of the midpoint P2, a solid 121 of a sublimable substance including camphor and IPA is formed by precipitation or solidification.

[0157] exist Fig.11 In the example, the thick straight line from point P2 to point P3 indicates that the first dissolution process is performed ( Fig. 9 Step S9). When performing the first dissolution process ( Fig. 9In step S9), 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. Thus, at least a part of the solid 121 of the sublimable substance melts or dissolves and returns to the solution of camphor and IPA.

[0158] exist Fig.11 In the example, the thick straight line from point P3 to point P4 indicates the execution of the final precipitation step ( Fig. 9 As mentioned above, in the final precipitation step ( Fig. 9 In step S11), the temperature of the camphor and IPA solution is not lowered to precipitate the sublimable substance solid 121 again, but the camphor and IPA solution is maintained at a temperature higher than room temperature and IPA is further evaporated. Fig. 9 The solid 121 of the sublimable substance precipitated in step S8) is a solid 121 of the sublimable substance having a smaller content than that of IPA.

[0159] After the solid 121 of the sublimable substance is precipitated between the patterns PA, a sublimation process is performed ( Fig. 9 In step S12), the solid 121 of the sublimable substance is sublimated and removed from the upper surface of the substrate W.

[0160] Specifically, when the shielding member 51 is in the lower position, the rotary motor 14 maintains the rotation speed of the substrate W at the sublimation speed. The sublimation speed may be equal to the liquid supply speed or may be different therefrom. In addition, the upper gas valve 57 is opened, and the central nozzle 55 starts to spray nitrogen. Alternatively, 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 nitrogen sprayed from the upper central opening 61 of the shielding member 51.

[0161] When the rotation of the substrate W starts at a sublimation speed, 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 through the space between the substrate W and the shielding member 51, and is exhausted from above the substrate W. And, after a certain time has passed since the sublimation starts, as shown in FIG. Fig.10F As shown, all the solids 121 of the sublimable substance are removed from the substrate W. Then, the rotation motor 14 is stopped, and the rotation of the substrate W is stopped ( Fig. 9 In step S13), the upper gas valve 57 is closed and the central nozzle 55 stops spraying nitrogen.

[0162] Next, carry out the unloading process ( Fig. 9 In step S14), the substrate W is moved out of the chamber 4.

[0163] Specifically, the shielding member lifting unit 54 raises the shielding member 51 to the upper position, and the baffle lifting unit 27 lowers all the baffles 24 to the lower position. In addition, 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 spin base 12 stop spraying nitrogen. Then, the central robot CR causes the arm H1 to enter the chamber 4. After the plurality of chuck pins 11 release the grip of the substrate W, the central robot CR uses the arm H1 to support the substrate W on the spin chuck 10. Then, the central robot CR supports the substrate W with the arm H1 and withdraws the arm H1 from the inside of the chamber 4. Thus, the processed substrate W is moved out of the chamber 4.

[0164] Second processing example

[0165] Next, an example (second processing example) of processing the substrate W when the drying pre-processing liquid is a solution of camphor and methanol will be described.

[0166] like Fig. 9 As shown, the general process of the second processing example is the same as that of the first processing example. The second processing example starts from the first dissolution step ( Fig. 9 Step S9) to the final precipitation step ( Fig. 9 The process of step S11) is different from that of the first processing example, and the other processes are the same as those of the first processing example. Therefore, the processes from the first dissolution process to the final precipitation process in the second processing example are described below.

[0167] 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 , appropriate reference FIG. 12A to FIG. 12D .

[0168] In the first precipitation step ( Fig. 9 After the solid 121 of the sublimable substance is precipitated in step S8), the first dissolution step ( Fig. 9 In step S9), the solid 121 of the sublimable substance is dissolved in the drying pre-treatment liquid on the substrate W.

[0169] Specifically, when the shielding member 51 is in the lower position and at least one baffle 24 is in the upper position, the rotary motor 14 maintains the rotation speed of the substrate W at the first dissolution speed. The first dissolution speed may be equal to the liquid supply speed or may be different therefrom. 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 shielding member 51, the control device 3 may close the upper gas valve 64. Alternatively, the control device 3 may reduce the flow rate of the nitrogen gas ejected from the upper central opening 61 of the shielding member 51 by changing the opening of the flow regulating valve 65.

[0170] In the first precipitation step ( Fig. 9 When the solvent evaporates from the pre-drying liquid in step S8), the heat of the pre-drying liquid equivalent to the heat of vaporization is released into the ambient gas in the chamber 4 together with the solvent, and the surface temperature of the pre-drying liquid decreases. If the solid 121 of the sublimable substance is formed, the solvent evaporated from the pre-drying liquid decreases, so the heat of the pre-drying liquid released into the ambient gas also decreases. At the same time, Fig. 12A As shown, the heat in the atmosphere is transferred to the pre-drying treatment liquid through the sublimable substance solid 121. As a result, the temperature of the sublimable substance solid 121 and the pre-drying treatment liquid on the substrate W rises.

[0171] like Fig. 12B As shown, if the temperature of the sublimable substance solid 121 and the drying pre-treatment liquid on the substrate W rises, a part of the sublimable substance solid 121 dissolves in the drying pre-treatment liquid. The drying pre-treatment liquid is a solution of camphor and methanol. The sublimable substance solid 121 contains camphor. The solubility of camphor in methanol is greater than the solubility of camphor in IPA, and camphor is easily soluble in methanol. If a part of the camphor solid is dissolved in the methanol liquid, the remaining camphor solid is also immediately dissolved in the methanol liquid. Thus, all or most of the sublimable substance solid 121 is dissolved in the drying pre-treatment liquid on the substrate W. Fig. 12C An example is shown in which all the solids 121 of the sublimable substance are dissolved in the pre-drying treatment liquid.

[0172] If 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 solid 121 of the sublimable substance is precipitated again on the surface of the pre-drying treatment liquid ( Fig. 9 If 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 S10).

[0173] Thus, when the drying pretreatment liquid is a solution of camphor and methanol, even if the temperature of the drying pretreatment liquid is not forcibly changed and the drying pretreatment liquid is simply placed on the upper surface of the substrate W, the precipitation and dissolution of the solid 121 of the sublimable substance can be repeated. Fig. 9 Step S8) to the first dissolution step ( Fig. 9The number of repetitions of a repetitive cycle of step S9) increases with the increase of the time of placing the dry pre-treatment liquid. Therefore, as long as the number of repetitions of precipitation and dissolving of the solid 121 of the sublimable substance is set according to the allowed time.

[0174] When the solid 121 of the sublimable substance is precipitated, the vapor pressure of the solvent in the ambient gas of the pre-drying treatment liquid in contact with the substrate W is maintained to be lower than the saturated vapor pressure of the solvent at the ambient gas temperature. 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 is maintained to be a certain value, which is higher than 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.

[0175] When the solid 121 of the sublimable substance is precipitated and dissolved, the control device 3 can make at least one of the central nozzle 55 and the upper central opening 61 of the shielding member 51 spray gas such as nitrogen at a low flow rate. In this case, the vapor of the solvent can be quickly removed from above the substrate W to promote the evaporation of the solvent. In addition, if the gas is sprayed toward the upper surface of the substrate W at a low flow rate, the temperature change of the interface between the solid 121 of the sublimable substance and the drying pre-treatment liquid can be controlled to a minimum. Therefore, the dissolution of the solid 121 of the sublimable substance can be not hindered, and the evaporation of the solvent can be promoted.

[0176] The FFU 6 usually supplies clean air into the chamber 4. The downward flow of the clean air flowing toward the upper surface of the substrate W is interrupted by the shielding member 51. Thus, the turbulence of the ambient gas on the substrate W can be suppressed. When the solid 121 of the sublimable substance is precipitated and dissolved, the control device 3 can temporarily stop the supply of clean air to the FFU 6. In addition, in order to suppress the turbulence of the ambient gas on the substrate W, the control device 3 can 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.

[0177] After the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid, the final precipitation step ( Fig. 9 In step S11), the solid 121 of the sublimable substance is precipitated again.

[0178] Specifically, when the shielding member 51 is in the lower position and at least one baffle 24 is in the upper position, the rotary motor 14 maintains the rotation speed of the substrate W at the final precipitation speed. The final precipitation speed may be equal to the liquid supply speed or may be different therefrom. While the substrate W rotates at the final precipitation speed, the solvent evaporates from the surface of the pre-drying liquid. If the concentration of the sublimable substance in the pre-drying liquid reaches the saturation concentration of the sublimable substance in the pre-drying liquid, a solid 121 of the sublimable substance is precipitated on the upper surface of the substrate W, and all or almost all of the pre-drying liquid disappears from the substrate W (see Fig.10E Then, the sublimation process is performed ( Fig. 9 In step S12), the solid 121 of the sublimable substance on the substrate W is sublimated.

[0179] As described above, when the drying pretreatment liquid is a solution of camphor and methanol, the solid 121 of the sublimable substance can be repeatedly precipitated and dissolved by simply placing the drying pretreatment liquid on the upper surface of the substrate W. In the case where a trace amount of the drying pretreatment liquid remains on the substrate W, the solid 121 of the sublimable substance may be dissolved in the drying pretreatment liquid before the solid 121 of the sublimable substance is sublimated. In order to prevent this from happening, the solid 121 of the sublimable substance on the substrate W can be cooled. For example, the rotation speed of the substrate W can be increased, and the flow rate of the gas ejected toward the upper surface of the substrate W can also be increased.

[0180] Fig.13 : is a graph showing the collapse rate of pattern PA. Collapse rate A and collapse rate B are values ​​when the pre-drying treatment liquid is a solution of camphor and IPA, and collapse rate C is a value when the pre-drying treatment liquid is a solution of camphor and methanol.

[0181] "Collapse rate A" is a value when the solid 121 of the sublimable substance is sublimated after the solid 121 of the sublimable substance is precipitated once. "Collapse rate B" is a value when the solid 121 of the sublimable substance is sublimated after the solid 121 of the sublimable substance is precipitated twice. "Collapse rate C" is a value when the solid 121 of the sublimable substance is sublimated after the solid 121 of the sublimable substance is precipitated more than twice. Except for the composition of the pre-drying treatment liquid and the number of times the solid 121 of the sublimable substance is precipitated, the processing conditions of the substrate W in the collapse rates A to C are the same.

[0182] The collapse rate A is lower than the value when IPA drying is performed, wherein the IPA drying is performed by removing the IPA on the substrate W by high-speed rotation of the substrate W. The collapse rate B is lower than the collapse rate A. Similarly, the collapse rate C is lower than the collapse rate A. The collapse rate C is lower than the collapse rate B. The collapse rate B is less than half of the collapse rate A. The collapse rate C is less than half of the collapse rate B. The collapse rate C is extremely low, less than 1%.

[0183] Since the collapse rate B is lower than the collapse rate A, after the precipitated sublimation substance solid 121 is dissolved in the pre-drying liquid, if the sublimation substance solid 121 is precipitated again, the collapse rate of the pattern PA can be reduced. Since the collapse rate C is lower than the collapse rate B, when the sublimation substance is camphor, if methanol is used as a solvent instead of IPA, the collapse rate of the pattern PA can be further reduced. Therefore, even in the case where the strength of the pattern PA is extremely low, if the first precipitation step ( Fig. 9 Step S8) to the first dissolution step ( Fig. 9 The collapse rate of the pattern PA can also be reduced by performing a repeated cycle of step S9) more than once.

[0184] According to the research of the inventors of the present invention, in the interval G1 of the pattern PA (see Fig. 10A ) is less than 30nm, even if sublimation drying is performed, a good pattern PA collapse rate cannot be obtained. This is because an incomplete precipitation area where there is no or almost no sublimation substance solid 121 between the patterns PA is formed in the upper surface of the substrate W. Therefore, after the precipitated sublimation substance solid 121 is dissolved in the pre-drying treatment liquid, if the sublimation substance solid 121 is precipitated again, the pattern PA collapse rate can be reduced even for a substrate W in which the interval G1 of the pattern PA is less than 30nm.

[0185] Next, the change in film thickness of the pre-drying treatment liquid will be described.

[0186] Fig.14 1 is a graph showing a change over time in the thickness of the liquid film of the pre-drying treatment liquid 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 inserted figure in Fig.14 The aspect ratio of other parts of the image is different.

[0187] Fig.14 The multiple curves (solid line curve, dotted line curve, and dashed line curve) 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 film thickness of the pre-drying treatment liquid decreases with the passage of time.

[0188] exist Fig.14In the embodiment, the liquid film of the pre-drying treatment liquid is measured only to the time T1. This is because the solid 121 of the sublimable substance is precipitated at the time T1. In other words, the transparency of the solid 121 of the sublimable substance is lower than the transparency of the pre-drying treatment liquid, while the pre-drying treatment liquid is transparent. Therefore, if the solid 121 of the sublimable substance is precipitated, the detection value of the film thickness measuring unit 91 changes greatly, and the liquid film of the pre-drying treatment liquid cannot be measured.

[0189] If the solid 121 of the sublimable substance is precipitated, the detection value of the film thickness measuring unit 91 changes greatly, so the control device 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. In addition, the film thickness of the drying pretreatment liquid before the solid 121 of the sublimable substance is precipitated is substantially equal to the thickness of the solid 121 of the sublimable substance after the solid 121 of the sublimable substance is precipitated. Therefore, the control device 3 can measure the thickness of the solid 121 of the sublimable substance by measuring the film thickness of the drying pretreatment liquid.

[0190] In addition, if Fig.14 As shown in the figure, no matter what the concentration of the sublimable substance is, the film thickness of the pre-drying treatment liquid first decreases sharply and then decreases slowly. During the period when the film thickness of the pre-drying treatment liquid decreases sharply, there is almost no difference in the film thickness and the rate of decrease of the film thickness among a plurality of pre-drying treatment liquids with different concentrations of the sublimable substance. In other words, if the elapsed time is the same, the film thickness of the pre-drying treatment liquid decreases at a substantially same rate regardless of the concentration of the sublimable substance.

[0191] In contrast, Fig.14 As shown in the insert diagram in , during the period when the film thickness of the drying pre-treatment liquid is slowly reduced, the reduction speed of the film thickness of the drying pre-treatment liquid is different in multiple drying pre-treatment liquids with different concentrations of sublimable substances. This is because if the concentration of the sublimable substance changes, the viscosity of the drying pre-treatment liquid also changes. Therefore, if the reduction speed of the film thickness of multiple drying pre-treatment liquids with different concentrations of sublimable substances is measured and recorded in advance, the actual concentration of the sublimable substance in the drying pre-treatment liquid on the substrate W can be inferred by monitoring the liquid film of the drying pre-treatment liquid on the substrate W.

[0192] If the film thickness of the pre-drying treatment liquid before the solid 121 of the sublimable substance is the same, the thickness of the solid 121 of the sublimable substance increases as the concentration of the sublimable substance increases, and decreases as the concentration of the sublimable substance decreases. Therefore, by measuring the film thickness of the pre-drying treatment liquid and inferring the actual concentration of the sublimable substance, the thickness of the solid 121 of the sublimable substance can be inferred before the solid 121 of the sublimable substance is actually precipitated.

[0193] Fig.151 is a flow chart showing the process from the start of measuring the film thickness of the pre-drying treatment liquid to the precipitation of the solid 121 of the sublimable substance. Figure 2 , Figure 7 and Fig.15 .

[0194] In addition, when the drying pretreatment liquid is a solution of camphor and IPA, the film thickness of the drying pretreatment liquid can be measured each time the solid 121 of the sublimable substance is precipitated, or it can be measured only when the solid 121 of the sublimable substance is precipitated for the first time. Fig. 9 Step S8) and the final precipitation step ( Fig. 9 In the case where the pre-drying treatment liquid is a solution of camphor and methanol, the film thickness of the pre-drying treatment liquid can be measured only when the solid 121 of the sublimable substance is first precipitated.

[0195] When the film thickness of the pre-drying treatment liquid is measured, the control device 3 determines whether the ejection of the pre-drying treatment liquid is stopped according to whether the pre-drying treatment liquid valve 41 is opened ( Fig.15 Step S21). When the drying pre-treatment liquid nozzle 39 sprays the drying pre-treatment liquid ( Fig.15 In step S21, the control device 3 determines again whether the ejection of the pre-drying treatment liquid has stopped after a predetermined time has passed ( Fig.15 If the spraying of the pre-drying treatment liquid stops ( Fig.15 If the answer is "Yes" in step S21 of , the control device 3 causes the film thickness measuring unit 91 to start measuring the film thickness of the pre-drying treatment liquid ( Fig.15 Step S22).

[0196] While the film thickness measuring unit 91 measures the film thickness of the drying pre-treatment liquid, the control device 3 monitors the decreasing speed of the film thickness of the drying pre-treatment liquid according to the film thickness of the drying pre-treatment liquid. As mentioned above, the decreasing speed of the film thickness is related to the actual concentration of the sublimable substance in the drying pre-treatment liquid on the substrate W. The standard speed range representing the range of the decreasing speed of the film thickness is specified by the process specification. The control device 3 determines whether the decreasing speed of the film thickness is appropriate, that is, the control device 3 determines whether the decreasing speed of the film thickness exceeds the lower limit value of the standard speed range and is lower than the upper limit value of the standard speed range ( Fig.15 Step S23).

[0197] Due to some reason such as failure of the first flow control valve 107A or the second flow control valve 107B, the concentration of the sublimable substance exceeds the standard concentration range, and the film thickness reduction rate is greater than or equal to the upper limit of the standard speed range, or less than or equal to the lower limit of the standard speed range ( Fig.15In this case, the control device 3 makes the alarm device 100C (see Figure 8 )Send an alert( Fig.15 Then, the control device 3 executes the abnormality processing step ( Fig.15 The details of the abnormality handling process will be described later. In addition, the control device 3 stops the film thickness measuring unit 91 from measuring the film thickness of the pre-drying treatment liquid ( Fig.15 Step S29).

[0198] When the film thickness reduction rate is appropriate, that is, when the film thickness reduction rate exceeds the lower limit value of the standard speed range and is lower than the upper limit value of the standard speed range ( Fig.15 In step S23 of the invention, the control device 3 determines based on the detection value of the film thickness measuring unit 91 that the solid 121 of the sublimable substance is initially precipitated in 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 does not precipitate ( Fig.15 If the answer is "No" in step S26 of , the control device 3 determines again after a predetermined time whether the reduction speed of the film thickness is appropriate ( Fig.15 Step S23).

[0199] If a solid of sublimable substance 121 ( Fig.15 If the value in step S26 of the control device 3 is "yes", the control device 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 precipitated, that is, whether the thickness of the solid 121 of the sublimable substance exceeds the lower limit value of the standard thickness range and is lower than the upper limit value of the standard thickness range ( Fig.15 Step S27).

[0200] If the thickness of the solid 121 of the sublimable substance is appropriate ( Fig.15 If the answer is "Yes" in step S27 of , the control device 3 causes the film thickness measuring unit 91 to stop measuring the film thickness of the pre-drying treatment liquid ( Fig.15 Step S29). If the thickness of the solid 121 of the sublimable substance is not appropriate ( Fig.15 ) in step S27 of the control device 3, the control device 3 activates the alarm device 100C (see Figure 8 )Send an alert( Fig.15 Then, the film thickness measuring unit 91 stops measuring the film thickness of the pre-drying treatment liquid ( Fig.15 Step S29).

[0201] Fig.16A This is a schematic diagram for explaining an example of an abnormality handling process. Fig. 16B Fig. 16 is a schematic diagram for explaining another example of the abnormality handling process.

[0202] As described above, in order to determine whether the actual concentration of the sublimable substance contained in the pre-drying treatment liquid on the substrate W is appropriate, the control device 3 monitors the decreasing speed ( Fig.15 This is because, once the actual concentration of the sublimable substance becomes abnormal, in the final precipitation step ( Fig. 9 The thickness of the solid 121 of the sublimable substance precipitated in step S11) will be greater or less than the expected value. If the thickness of the solid 121 of the sublimable substance before sublimation is greater or less than the expected value, the collapse rate of the pattern PA will deteriorate.

[0203] If the actual concentration of the sublimable substance is abnormal due to the first flow rate adjustment valve 107A (see Figure 7 ) or the second flow control valve 107B (see Figure 7 ), the control device 3 can change the opening of at least one of the first flow regulating valve 107A and the second flow regulating valve 107B before the solid 121 of the sublimable substance precipitates.

[0204] For example, assuming that the actual concentration of the sublimable substance is greater than or equal to the upper limit of the standard concentration range, the control device 3 can change the opening of at least one of the first flow regulating valve 107A and the second flow regulating valve 107B so that the concentration of the sublimable substance in the pre-drying treatment liquid is equal to or less than the lower limit of the standard concentration range. If the actual concentration of the sublimable substance is less than or equal to the lower limit of the standard concentration range, the control device 3 can change the opening of at least one of the first flow regulating valve 107A and the second flow regulating valve 107B so that the concentration of the sublimable substance in the pre-drying treatment liquid is greater than or equal to the upper limit of the quasi-concentration range.

[0205] In addition, when the actual concentration of the sublimable substance is abnormal due to at least one of the first flow control valve 107A and the second flow control valve 107B failing, the control device 3 may implement the following steps: Fig.16A , Fig. 16B and Fig. 16C Any of the exception handling steps shown in ( Fig.15 Step S25).

[0206] Fig.16A The replacement liquid nozzle 43 shows a state in which a solvent corresponding to the replacement liquid is ejected toward the upper surface of the substrate W. Fig.16AThe 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.

[0207] like Fig.16A As shown, when the actual concentration of the sublimable substance is abnormal, the control device 3 can cause the replacement liquid nozzle 43 to spray the solvent. In this case, the drying pre-treatment liquid on the substrate W is replaced by the solvent to form a liquid film of the solvent covering the entire 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. After the drying pre-treatment liquid on the substrate W is replaced by the solvent, the drying pre-treatment liquid with an appropriate concentration of the sublimable substance can be supplied to the substrate W.

[0208] Fig. 16B The thickness of the pre-drying liquid on the substrate W is reduced. The thickness reduction can be achieved by increasing the rotation speed of the substrate W, by spraying a gas such as nitrogen toward the upper surface of the substrate W, or by both.

[0209] When increasing the rotation speed of the substrate W, the control device 3 increases the rotation speed of the rotation motor 14 (see Figure 2 When the gas is ejected toward the upper surface of the substrate W, the control device 3 may cause the central nozzle 55 to eject nitrogen gas, or may cause the upper central opening 61 (see Figure 2 ) to eject nitrogen. When at least one of the central nozzle 55 and the upper central opening 61 of the shielding member 51 has ejected nitrogen, the control device 3 may cause the flow regulating valve 58 (see Figure 2 ) and flow control valve 65 (see Figure 2 ) has an increased opening degree of at least one of the components.

[0210] When the actual concentration of the sublimation substance is greater than or equal to the upper limit of the standard concentration range, the thickness of the solid 121 of the sublimation substance before sublimation is greater than the desired value. If the film thickness of the drying pre-treatment liquid on the substrate W is reduced, the amount of the sublimation substance contained in the drying pre-treatment liquid on the substrate W is reduced, so the thickness of the solid 121 of the sublimation substance is also reduced. Therefore, when the actual concentration of the sublimation substance is greater than or equal to the upper limit of the standard concentration range, the control device 3 can reduce the film thickness of the drying pre-treatment liquid on the substrate W before the solid 121 of the sublimation substance is precipitated. In this way, even when the actual concentration of the sublimation substance is abnormal, the solid 121 of the sublimation substance with a desired thickness can be precipitated.

[0211] Fig. 16CThe state where the mist or vapor of the solvent is sprayed toward the upper surface of the substrate W is shown. Fig. 16C The 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 is shown. 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 serves as a carrier gas for transporting the mist or vapor of the solvent to the substrate W.

[0212] When nitrogen gas containing mist or vapor of IPA is sprayed toward the upper surface of the substrate W, nitrogen gas may be supplied to the IPA (liquid) in the tank (so-called bubbling). In this way, many nitrogen bubbles are formed in the IPA, and nitrogen gas containing mist or vapor of IPA is released from the surface of the IPA in the tank. The nitrogen gas may be sprayed from at least one of the central nozzle 55 and the upper central opening 61 of the shielding member 51.

[0213] If the mist or steam of solvent is sprayed toward the upper surface of substrate W, the vapor pressure of solvent in the ambient gas in contact with the drying pre-treatment liquid on substrate W rises. Therefore, the evaporation of solvent from the drying pre-treatment liquid is suppressed. On the other hand, because the vapor pressure of sublimation substance in the ambient gas is constant, although it is a trace amount, sublimation substance evaporates from the drying pre-treatment liquid. Therefore, when assuming that the actual concentration of sublimation substance is the upper limit value of the standard concentration range or slightly higher than the upper limit value, if the mist or steam of solvent is sprayed toward the upper surface of substrate W, even when the actual concentration of sublimation substance is abnormal, solid 121 of sublimation substance with desired thickness can be precipitated.

[0214] Fig.17 This represents the first precipitation step ( Fig. 9 From the beginning of step S8) to the first dissolution step ( Fig. 9 Flow chart of the detailed process from the beginning of step S9) to the beginning of step S9). Figure 2 , Figure 7 and Fig.17 .

[0215] In the film thickness reduction process ( Fig. 9 After the film thickness of the pre-drying treatment liquid is reduced in step S7), the control device 3 causes the film thickness measuring unit 91 to start measuring the film thickness of the pre-drying treatment liquid ( Fig.17 In step S31 of the present invention, the shielding member 51 is located at the lower position and at least one baffle 24 is located at the upper position. The rotation motor 14 maintains the rotation speed of the substrate W at the first precipitation speed. While the substrate W rotates at the first precipitation speed, the solvent evaporates from the surface of the drying pre-treatment liquid. As a result, the film thickness of the drying pre-treatment liquid on the substrate W gradually decreases ( Fig.17 In step S32), the concentration of the sublimable substance in the drying pre-treatment liquid increases.

[0216] The standard speed range indicating the range of the film thickness reduction speed is specified by the process specification. During the period when the film thickness measuring unit 91 measures the film thickness of the pre-drying treatment liquid, the control device 3 determines whether the film thickness reduction speed is appropriate, that is, the control device 3 determines whether the film thickness reduction speed exceeds the lower limit value of the standard speed range and is lower than the upper limit value of the standard speed range based on the detection value of the film thickness measuring unit 91 ( Fig.17 Step S33).

[0217] When the film thickness reduction rate is inappropriate, that is, when the film thickness reduction rate is greater than or equal to the upper limit value of the standard speed range or less than or equal to the lower limit value of the standard speed range ( Fig.17 In step S33, the control device 3 causes the alarm device 100C to sound an alarm ( Fig.17 Then, the control device 3 executes the above-mentioned abnormality processing step ( Fig.17 Then, the control device 3 stops the film thickness measuring unit 91 from measuring the film thickness of the pre-drying treatment liquid ( Fig.17 Step S39).

[0218] When the film thickness reduction rate is appropriate ( Fig.17 In step S33, the control device 3 determines whether the solid 121 of the sublimable substance is precipitated based on the detection value of the film thickness measuring unit 91 ( Fig.17 If the solid 121 of the sublimable substance does not precipitate ( Fig.17 If the answer is "No" in step S36 of , the control device 3 determines again after a predetermined time whether the reduction speed of the film thickness is appropriate ( Fig.17 Step S33).

[0219] If a solid of sublimable substance 121 ( Fig.17 If the value in step S36 of the control device 3 is "Yes", the control device 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 precipitated, that is, whether the thickness of the solid 121 of the sublimable substance exceeds the lower limit value of the standard thickness range and is lower than the upper limit value of the standard thickness range ( Fig.17 Step S37).

[0220] If the thickness of the solid 121 of the sublimable substance is not appropriate ( Fig.17 ) the control device 3 activates the alarm device 100C (see Figure 8 )Send an alert( Fig.17 The film thickness measuring unit 91 stops measuring the film thickness of the pre-drying treatment liquid ( Fig.17 Step S39). If the thickness of the solid 121 of the sublimable substance is appropriate ( Fig.17 If the answer is "Yes" in step S37 of , the control device 3 causes the film thickness measuring unit 91 to stop measuring the film thickness of the pre-drying treatment liquid ( Fig.17 Step S39).

[0221] After the precipitation of the solid 121 of the sublimable substance is confirmed, in order to perform the first dissolving step ( Fig. 9 In step S9), the control device 3 causes the lower surface nozzle 71 to spray warm water. Therefore, the drying pre-treatment liquid ( Fig.17 Step S40).

[0222] If the time from precipitation to sublimation of the solid 121 of the sublimable substance is short, the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid before the pre-drying treatment liquid is heated, that is, part or all of the solid 121 of the sublimable substance may have sublimated before the pre-drying treatment liquid is heated. In such a case, if it is monitored whether the solid 121 of the sublimable substance is precipitated, the pre-drying treatment liquid can be heated at the most appropriate time, and the sublimable solid 121 of the sublimable substance that is sublimated unintentionally can be reduced.

[0223] As described above, in the present embodiment, a solution of a sublimable substance and a solvent, which is equivalent to the drying pre-treatment liquid, is supplied to the upper surface of the substrate W. Thus, a liquid film of the drying pre-treatment liquid is formed on the upper surface of the substrate W. Then, the solvent is evaporated from the drying pre-treatment liquid. The concentration of the sublimable substance in the drying pre-treatment liquid rises as the solvent evaporates. If the concentration of the sublimable substance reaches the saturation concentration of the sublimable substance, a solid 121 of the sublimable substance is precipitated from the drying pre-treatment liquid.

[0224] When the solid 121 of the sublimable substance begins to precipitate, the pre-drying treatment liquid remains on the upper surface of the substrate W. The pre-drying treatment liquid is made to dissolve at least a portion of the solid 121 of the sublimable substance. Then, the solvent is evaporated from the pre-drying treatment liquid again. As a result, 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. Then, the solid 121 of the sublimable substance is sublimated and removed from the substrate W. In this way, the pre-drying treatment liquid is removed from the substrate W, and the substrate W is dried.

[0225] Before the solid 121 of the sublimable substance is first precipitated, the drying pretreatment 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 drying pretreatment liquid existing between the patterns PA has different properties from the matrix of the drying pretreatment liquid, that is, the drying pretreatment liquid existing between the patterns PA has different properties from the drying pretreatment liquid located in the range from the surface (upper surface) of the drying pretreatment liquid to the upper surface of the pattern PA. The difference in properties between the two becomes significant as the interval G1 of the pattern PA becomes narrower.

[0226] If the interval G1 of the pattern PA is narrow, when the solid 121 of the sublimable substance is initially precipitated, the solid 121 of the sublimable substance is precipitated only in the matrix of the drying pretreatment liquid, and an incomplete precipitation region where there is no or almost no solid 121 of the sublimable substance between the patterns PA is formed on the upper surface of the substrate W. In this case, the surface tension of the drying pretreatment 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 region collapses. This causes an increase (deterioration) in the collapse rate of the pattern PA.

[0227] In contrast, if the precipitated sublimation substance solid 121 is dissolved in the pre-drying treatment liquid and then precipitated again, the crystal nucleus of the sublimation substance solid 121 can be formed even in a narrow space such as the space between the patterns PA. Therefore, if the precipitated sublimation substance solid 121 is dissolved in the pre-drying treatment liquid and then precipitated again, even if the interval G1 of the pattern PA is narrow, the incomplete precipitation area can be prevented from occurring or its area can be reduced. As a result, the collapse of the pattern PA can be reduced and the collapse rate of the pattern PA can be reduced.

[0228] In this embodiment, the solvent is not evaporated from the drying pretreatment liquid by heating the drying pretreatment liquid, but the drying pretreatment liquid is maintained at a temperature less than or equal to room temperature, and the solvent is evaporated from the drying pretreatment liquid. 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. 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.

[0229] In contrast, if the solvent is evaporated from the drying pretreatment liquid by heating the drying pretreatment liquid, 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. After the concentration of the sublimable substance rises, if the drying pretreatment liquid is cooled naturally or forcibly to precipitate the solid 121 of the sublimable substance, most or all of the matrix of the drying pretreatment liquid may be changed into the solid 121 of the sublimable substance.

[0230] If the pre-drying treatment liquid does not remain above the pattern PA, the sublimable substance solid 121 will not be efficiently 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 not as good as the efficiency of the sublimable substance solid 121 dissolving in the matrix of the pre-drying treatment liquid. Therefore, by maintaining a part of the matrix of the pre-drying treatment liquid as liquid, the sublimable substance solid 121 can be efficiently dissolved in the pre-drying treatment liquid.

[0231] In the present embodiment, the drying pre-treatment liquid on the upper surface of the substrate W is heated to increase the temperature of the drying pre-treatment liquid to a value higher than the room temperature. The dissolution of the solid 121 of the sublimable substance into the drying pre-treatment liquid can be promoted by the temperature rise of the drying pre-treatment liquid. Thus, the solid 121 of the sublimable substance can be efficiently dissolved in the drying pre-treatment liquid. In addition, since the solid 121 of the sublimable substance begins to be forcibly dissolved as the heating begins, the solid 121 of the sublimable substance can be forcibly dissolved at any time by changing the timing of starting the heating.

[0232] In this embodiment, the solid 121 of the sublimable substance and the pre-treatment liquid for drying are not directly heated from above the substrate W, but the solid 121 of the sublimable substance and the pre-treatment liquid for drying are indirectly heated via the substrate W. If the solid 121 of the sublimable substance and the pre-treatment liquid for drying are heated from above the substrate W, a part of the solid 121 of the sublimable substance on the surface of the pre-treatment liquid for drying will sublime. In this case, not only a part of the sublimable substance is wasted, but also the thickness of the final solid 121 of the sublimable substance is less than the expected value. If the solid 121 of the sublimable substance and the pre-treatment liquid for drying are heated via the substrate W, the loss of such sublimable substance can be reduced.

[0233] In this embodiment, in order to precipitate the solid 121 of the sublimable substance on the substrate W, the drying pretreatment liquid is heated and the solvent is evaporated from the drying pretreatment liquid. Thus, the solid 121 of the sublimable substance is precipitated from the high-temperature drying pretreatment liquid. The saturation concentration of the sublimable substance in the drying pretreatment liquid increases as the temperature of the drying pretreatment liquid increases. The proportion 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 can generate a collapsing force that causes the pattern PA to collapse. Therefore, by reducing the content of the solvent, the collapse rate of the pattern PA can be further reduced.

[0234] In the present embodiment, the solid 121 of sublimable substance is separated out on the surface of the drying pre-treatment liquid. When the solvent evaporates from the drying pre-treatment liquid, the heat of the drying pre-treatment liquid equivalent to the heat of vaporization is released into the ambient gas together with the solvent, and the temperature on the surface of the drying pre-treatment liquid is reduced. If the solid 121 of sublimable substance is formed, the solvent evaporated from the drying pre-treatment liquid is reduced, so the heat of the drying pre-treatment liquid released into the ambient gas is also reduced. Meanwhile, the heat in the ambient gas is transferred to the drying pre-treatment liquid via the solid 121 of sublimable substance. Thus, the temperature of the interface between the solid 121 of sublimable substance and the drying pre-treatment liquid rises. Therefore, even if the drying pre-treatment liquid on the substrate W is not forced to be heated, the solid 121 of sublimable substance can be dissolved in the drying pre-treatment liquid.

[0235] Other Implementations

[0236] The present invention is not limited to the contents of the above-described embodiment, and various modifications are possible.

[0237] For example, in the first precipitation step ( Fig. 9 In step S8), the pre-drying treatment liquid on the substrate W may not be maintained at a temperature less than or equal to room temperature, but may be heated at a heating temperature higher than room temperature to evaporate the solvent from the pre-drying treatment liquid on the substrate W.

[0238] In the final precipitation step of the first treatment example ( Fig. 9 In step S11), instead of evaporating the solvent from the pre-drying treatment liquid while heating the pre-drying treatment liquid on the substrate W, the solvent may be evaporated from the pre-drying treatment liquid while stopping forced heating of the pre-drying treatment liquid on the substrate W.

[0239] When the solid 121 of the sublimable substance is dissolved in the pre-drying treatment liquid, instead of supplying warm water as an example of a heating liquid higher than room temperature to the lower surface of the substrate W, a heating gas higher than room temperature may be sprayed to the upper surface or the lower surface of the substrate W. For example, nitrogen gas 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 or a lamp that emits light to the substrate W may be arranged on at least one side above and below the substrate W. For example, the heating element may be placed in at least one of the rotating base 12 and the shielding member 51.

[0240] The solid 121 of the sublimable substance may be removed by using a processing unit 2 different from the wet processing unit 2w. The processing unit 2 for removing the solid 121 of the sublimable substance 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. That is, 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 solid 121 of the sublimable substance are arranged in the same substrate processing system, and before removing the solid 121 of the sublimable substance, the substrate W may be transported from the substrate processing apparatus 1 to another substrate processing apparatus 1.

[0241] When replacing the rinsing liquid on the substrate W with pure water or the like by drying the pretreatment liquid, the drying pretreatment liquid supplying step may be performed instead of performing the replacement liquid supplying step of replacing the rinsing liquid on the substrate W with the replacement liquid.

[0242] The shielding member 51 may include a cylindrical portion extending downward from the outer circumference of the circular plate portion 52 in addition to the circular plate portion 52. In this case, when the shielding member 51 is arranged in the lower position, the substrate W held by the spin chuck 10 is surrounded by the cylindrical portion.

[0243] The shielding member 51 can rotate around the rotation axis A1 together with the spin chuck 10. For example, the shielding member 51 can be disposed on the spin base 12 in a manner that does not contact the substrate W. In this case, since the shielding member 51 is connected to the spin base 12, the shielding member 51 rotates in the same direction as the spin base 12 at the same speed.

[0244] The shielding member 51 may be omitted. However, when supplying liquid such as pure water to the lower surface of the substrate W, it is preferable to provide the shielding member 51. This is because the shielding member 51 can shield the droplets flowing back from the lower surface of the substrate W to the upper surface of the substrate W along the outer peripheral surface of the substrate W and the droplets rebounding from the processing cup 21 to the inside, and can reduce the liquid mixed with the drying pre-processing liquid on the substrate W.

[0245] 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 can be omitted.

[0246] When the light of the light emitting element 92 is incident approximately vertically on the upper surface of the substrate W, the housing 93 of the film thickness measuring unit 91 can accommodate not only the light emitting element 92 but also the light receiving element 97. In this case, the light of the light emitting element 92 reflected on the upper surface of the substrate W (reflected light) passes through the opening of the housing 93 closed by the transparent plate 94 and is received by the light receiving element 97 in the housing 93.

[0247] When both the light emitting element 92 and the light receiving element 97 are accommodated in the housing 93, the control device 3 can horizontally move the housing 93 to move the incident position of the light of the light emitting element 92 on the upper surface of the substrate W along the radial direction of the substrate W. Specifically, a scanning arm holding the housing 93 and an electric actuator for horizontally moving the scanning arm in the chamber 4 can be arranged on the processing unit 2 above the substrate W held by the spin chuck 10.

[0248] 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 include an air conditioner for adjusting the temperature in the substrate processing apparatus 1.

[0249] When the drying pretreatment liquid is a solution of camphor and methanol, if the temperature in the substrate processing device 1, more specifically, if 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 placed only 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. Thus, the precipitation and dissolution of the sublimable substance are naturally repeated.

[0250] When the temperature in the clean room is lower than the surface temperature during precipitation, the control device 3 can make the air conditioner adjust the temperature in the substrate processing device 1 to maintain the temperature of the internal space of the chamber 4 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 control device 3 can change the FFU6 (see Figure 2 ) output and exhaust valve 9 (see 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.

[0251] The substrate processing apparatus 1 may 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 processing of the substrate W by the processing unit 2, the control device 3 may stop loading the next substrate W 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.

[0252] 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.

[0253] Two or more of all the aforementioned structures may be combined. Two or more of all the aforementioned steps may be combined.

[0254] The control device 3 is an example of the first precipitation unit, the first dissolution unit and the final precipitation unit. The drying pre-treatment liquid nozzle 39 is an example of the drying pre-treatment liquid supply unit. The drying pre-treatment liquid supply unit 101 is an example of the drying pre-treatment liquid supply unit. The spin chuck 10 and the center nozzle 55 are an example of the sublimation unit.

[0255] 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 limited to these specific examples. The spirit and scope of the present invention are limited only by the appended claims.

Claims

1. A substrate drying method, wherein: include: a drying pretreatment liquid supplying step of supplying a drying pretreatment liquid to the upper surface of the substrate on which the pattern is formed, and forming a liquid film of the drying pretreatment liquid on the upper surface of the substrate, wherein the drying pretreatment liquid is a solution containing a sublimable substance corresponding to a solute and a solvent in which the sublimable substance is dissolved; a first precipitation step of precipitating a solid of the sublimable substance in the pre-drying treatment liquid on the upper surface of the substrate by evaporating the solvent from the pre-drying treatment liquid on the upper surface of the substrate; a first dissolving step of dissolving at least a portion of the solid of the sublimable substance in the pre-drying treatment liquid on the upper surface of the substrate; a final precipitation step of precipitating the solid of the sublimable substance on the upper surface of the substrate by evaporating the solvent from the pre-drying treatment liquid in which the solid of the sublimable substance is dissolved; a sublimation step of removing the solid of the sublimable substance from the upper surface of the substrate by sublimating the solid of the sublimable substance; The first precipitation step includes: a room temperature precipitation step, by maintaining the pre-drying treatment liquid on the upper surface of the substrate at a temperature less than or equal to room temperature, and evaporating the solvent from the pre-drying treatment liquid on the upper surface of the substrate, thereby precipitating the solid of the sublimable substance in the pre-drying treatment liquid on the upper surface of the substrate.

2. The substrate drying method according to claim 1, wherein: The first dissolving step includes a heating step of heating the pre-drying treatment liquid on the upper surface of the substrate at a heating temperature higher than room temperature.

3. A substrate drying method, wherein: include: a drying pretreatment liquid supplying step of supplying a drying pretreatment liquid to the upper surface of the substrate on which the pattern is formed, and forming a liquid film of the drying pretreatment liquid on the upper surface of the substrate, wherein the drying pretreatment liquid is a solution containing a sublimable substance corresponding to a solute and a solvent in which the sublimable substance is dissolved; a first precipitation step of precipitating a solid of the sublimable substance in the pre-drying treatment liquid on the upper surface of the substrate by evaporating the solvent from the pre-drying treatment liquid on the upper surface of the substrate; a first dissolving step of dissolving at least a portion of the solid of the sublimable substance in the pre-drying treatment liquid on the upper surface of the substrate; a final precipitation step of precipitating the solid of the sublimable substance on the upper surface of the substrate by evaporating the solvent from the pre-drying treatment liquid in which the solid of the sublimable substance is dissolved; a sublimation step of removing the solid of the sublimable substance from the upper surface of the substrate by sublimating the solid of the sublimable substance; The first dissolving step includes: a heating step of heating the pre-drying treatment liquid on the upper surface of the substrate at a heating temperature higher than room temperature; The heating step includes an indirect heating step of heating the substrate from below the substrate to heat the pre-drying treatment liquid on the upper surface of the substrate at the heating temperature.

4. A substrate drying method, wherein: include: a drying pretreatment liquid supplying step of supplying a drying pretreatment liquid to the upper surface of the substrate on which the pattern is formed, and forming a liquid film of the drying pretreatment liquid on the upper surface of the substrate, wherein the drying pretreatment liquid is a solution containing a sublimable substance corresponding to a solute and a solvent in which the sublimable substance is dissolved; a first precipitation step of precipitating a solid of the sublimable substance in the pre-drying treatment liquid on the upper surface of the substrate by evaporating the solvent from the pre-drying treatment liquid on the upper surface of the substrate; a first dissolving step of dissolving at least a portion of the solid of the sublimable substance in the pre-drying treatment liquid on the upper surface of the substrate; a final precipitation step of precipitating the solid of the sublimable substance on the upper surface of the substrate by evaporating the solvent from the pre-drying treatment liquid in which the solid of the sublimable substance is dissolved; a sublimation step of removing the solid of the sublimable substance from the upper surface of the substrate by sublimating the solid of the sublimable substance; The first dissolving step includes: a heating step of heating the pre-drying treatment liquid on the upper surface of the substrate at a heating temperature higher than room temperature; The final precipitation step includes the step of heating the pre-drying treatment liquid on the upper surface of the substrate at the heating temperature and evaporating the solvent from the pre-drying treatment liquid on the upper surface of the substrate, thereby precipitating a solid of the sublimable substance on the upper surface of the substrate.

5. A method for drying a substrate, wherein: include: a drying pretreatment liquid supplying step of supplying a drying pretreatment liquid to the upper surface of the substrate on which the pattern is formed, and forming a liquid film of the drying pretreatment liquid on the upper surface of the substrate, wherein the drying pretreatment liquid is a solution containing a sublimable substance corresponding to a solute and a solvent in which the sublimable substance is dissolved; a first precipitation step of precipitating a solid of the sublimable substance in the pre-drying treatment liquid on the upper surface of the substrate by evaporating the solvent from the pre-drying treatment liquid on the upper surface of the substrate; a first dissolving step of dissolving at least a portion of the solid of the sublimable substance in the pre-drying treatment liquid on the upper surface of the substrate; a final precipitation step of precipitating the solid of the sublimable substance on the upper surface of the substrate by evaporating the solvent from the pre-drying treatment liquid in which the solid of the sublimable substance is dissolved; a sublimation step of removing the solid of the sublimable substance from the upper surface of the substrate by sublimating the solid of the sublimable substance; The first precipitation step includes: a liquid surface precipitation step of evaporating the solvent from the pre-drying treatment liquid on the upper surface of the substrate, thereby precipitating a solid of the sublimable substance on the surface of the pre-drying treatment liquid on the upper surface of the substrate; The first dissolution process includes: a natural dissolution process, causing the temperature of the pre-drying treatment liquid to rise by the heat of the ambient gas in contact with the solid of the sublimable substance, or increasing the temperature of the pre-drying treatment liquid by utilizing the heat of the ambient gas in contact with the solid of the sublimable substance, so that at least a portion of the solid of the sublimable substance is dissolved in the pre-drying treatment liquid on the upper surface of the substrate, or at least a portion of the solid of the sublimable substance is dissolved.

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