Substrate processing apparatus and substrate processing method

Abstract

To provide a substrate processing apparatus and a substrate processing method, which, when removing a liquid adhering to a substrate surface by batch processing, can reduce the occurrence of pattern collapse by controlling the film thickness of a solidified film in accordance with the temperature of the processing liquid.SOLUTION: A substrate processing apparatus 1 includes a chamber 70, a processing tank 11 that stores a processing liquid containing a sublimable substance and a solvent, a holding unit 20 that collectively holds a group of substrates W in a standing posture, a lifting mechanism 23 that raises and lowers the holding unit 20 relative to the processing tank 11 to immerse the holding unit 20 in the processing liquid or remove the holding unit from the processing liquid, and a vaporized gas supply unit 30 that supplies, into the chamber 70, at least vaporized gas produced by vaporizing an organic solvent. The purpose of immersion and removal is to evaporate the solvent while collectively lifting up the group of substrates W immersed in the processing liquid, thereby precipitating the sublimable substance and forming a solidified film containing the sublimable substance on a surface of the substrates W. The vaporized gas dissolves in the processing liquid, and the surface tension of the organic solvent is less than that of the solvent.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method capable of collectively performing sublimation drying on a plurality of substrates on which a stack such as a three-dimensional NAND structure is formed, by batch processing. [Background technology]

[0002] In the manufacturing process of a semiconductor device, a processing liquid is supplied to a substrate surface in the process of wet etching or surface cleaning, and then a process of drying the substrate surface is performed. However, for example, when a pattern with a large aspect ratio is formed on the substrate surface, there is a concern that the Laplace pressure of the processing liquid acts on the pattern when the processing liquid is dried, causing the pattern to collapse. In recent years, with the development of next-generation devices using miniaturization and new materials, a technology is required to suppress the collapse of a pattern formed on a substrate surface. Here, a sublimation drying technology that solidifies a processing liquid to form a solidified film and further sublimates and removes the solidified film can prevent or reduce the Laplace pressure derived from the processing liquid from acting on the pattern. Therefore, this technology is considered promising as a technology that can suppress the collapse of a pattern.

[0003] Sublimation drying technology in substrate processing is being established in the single-wafer processing in which substrates are processed one by one (for example, Patent Document 1 below). However, sufficient sublimation drying technology has not been established in the batch processing in which multiple substrates are processed at once. For example, in a 3D NAND structure such as a 3D NAND flash memory, a batch phosphoric acid treatment is required, but if the sublimation drying technology is not used, there is a concern that the pattern will collapse. Therefore, there is a demand for the establishment of a batch sublimation drying technology. However, when the sublimation drying of the substrate surface is performed in the batch process, there is a problem that the surface tension of the processing liquid acts on the pattern during the formation of a solidified film on the substrate surface, causing the pattern to collapse. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2000-70873 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention aims to provide a substrate processing apparatus and a substrate processing method that can reduce or prevent the occurrence of pattern collapse by minimizing the surface tension of a processing liquid acting on a pattern when a solidified film of the processing liquid is formed during sublimation drying of a substrate surface in a batchwise manner. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the substrate processing apparatus according to the present invention is a substrate processing apparatus for processing a surface of a substrate, comprising a chamber, a processing tank accommodated in the chamber and storing a processing liquid containing a sublimable substance and a solvent, a holding unit for collectively holding a plurality of the substrates in an upright position, a lifting mechanism for raising and lowering the holding unit relative to the processing tank to immerse the holding unit in the processing liquid or remove it from the processing liquid, and a vaporization gas supply unit for supplying at least a vaporization gas obtained by vaporizing an organic solvent into the chamber, wherein the immersion and removal are performed for evaporating the solvent while pulling up the plurality of substrates immersed in the processing liquid collectively to precipitate the sublimable substance and form a solidified film containing the sublimable substance on the surface of the substrate, and wherein the vaporization gas dissolves in the processing liquid, and the surface tension of the organic solvent is smaller than the surface tension of the solvent.

[0007] According to the above-mentioned configuration, the processing tank stores a processing liquid containing a sublimable substance and a solvent, the holding part holds a plurality of substrates in an upright position, and the lifting mechanism can raise and lower the holding part holding the plurality of substrates relative to the processing tank. Therefore, in the above-mentioned configuration, the plurality of substrates are immersed together in the processing liquid containing a sublimable substance and a solvent, and then the plurality of substrates are lifted up together in an upright position from the processing liquid, so that during the lifting up, a solidified film can be formed on the surface of each substrate while the solvent is evaporated to precipitate the sublimable substance.

[0008] Here, the substrate processing apparatus of the above configuration further includes a vaporization gas supply unit that supplies at least a vaporization gas obtained by vaporizing the organic solvent into the chamber in which the processing tank is accommodated. Therefore, the lifting mechanism can lift the substrates from the processing liquid under an atmosphere containing at least the vaporization gas of the organic solvent. In addition, since the vaporization gas is soluble in the processing liquid, the vaporization gas is also dissolved in the meniscus portion where the processing liquid contacts the substrate surface, resulting in an increase in the concentration of the organic solvent. Here, since the surface tension of the organic solvent is smaller than the surface tension of the solvent contained in the processing liquid, when the concentration of the organic solvent increases in the meniscus portion, the surface tension of the processing liquid in the meniscus portion also decreases due to this. As a result, a so-called Marangoni flow can be generated in which the processing liquid on the substrate surface flows so as to be drawn into the processing liquid on the processing tank side. The generation of the Marangoni flow acts to improve the liquid drainage of the processing liquid on the substrate surface, so that the time during which the sublimable substance is precipitated by the evaporation of the solvent to form a solidified film is made shorter than the time during which the surface tension of the processing liquid acts on the pattern to cause the pattern to collapse. As a result, compared to conventional substrate processing apparatuses, it is possible to form a solidified film while reducing or preventing the occurrence of pattern collapse.

[0009] In the above configuration, it is preferable that the boiling point of the solvent is lower than the boiling point of the organic solvent. This makes it easier for the solvent contained in the processing liquid to evaporate in the meniscus portion compared to the organic solvent after dissolution. As a result, the concentration of the organic solvent in the meniscus portion can be further increased, and the Marangoni flow in which the processing liquid on the substrate surface is drawn into the processing liquid in the processing tank side can be further increased. This further improves the drainage of the processing liquid on the substrate surface, so that a solidified film can be reliably formed before the surface tension of the processing liquid acts on the pattern and causes the pattern to collapse.

[0010] In the above-mentioned configuration, it is preferable to further include an exhaust section for exhausting gas from within the chamber to the outside.

[0011] Furthermore, in the above configuration, it is preferable to further include a vaporized gas concentration detector that detects the concentration of the vaporized gas in the chamber.

[0012] In order to solve the above-mentioned problems, the substrate processing method of the present invention is a substrate processing method for processing a surface of a substrate, comprising: an immersion step of immersing a plurality of the substrates together in a processing liquid containing a sublimable substance and a solvent and stored in a processing tank; and a solidified film forming step of evaporating the solvent while pulling up the plurality of the substrates together in an upright position to precipitate the sublimable substance and form a solidified film containing the sublimable substance on the pattern formation surface, wherein the solidified film forming step is performed in a chamber under an atmosphere containing at least a vaporized gas obtained by vaporizing an organic solvent, the vaporized gas dissolves in the processing liquid, and the surface tension of the organic solvent is smaller than the surface tension of the solvent.

[0013] In the above-mentioned configuration, by immersing a plurality of substrates in the treatment liquid at once, for example, liquid adhering to the substrate surface can be replaced with the treatment liquid (immersion process). Next, the plurality of substrates are pulled up in an upright position from the treatment liquid at once, and during this pulling up, the solvent in the treatment liquid is evaporated to precipitate a sublimable substance, thereby forming a solidified film on the surface of each substrate (solidified film formation process). Here, when pulling up the substrates, the surface tension of the treatment liquid acts on the pattern, causing the pattern to collapse. However, in the above-mentioned configuration, the solidified film formation process is performed in an atmosphere containing at least a vaporized gas of an organic solvent. Also, an organic solvent that dissolves the vaporized gas in the treatment liquid and has a surface tension smaller than that of the solvent is used as the organic solvent. As a result, in the above-mentioned configuration, when pulling up a plurality of substrates at once, the vaporized gas can be dissolved in the meniscus where the treatment liquid contacts the substrate surface. Dissolution of the vaporized gas in the meniscus increases the concentration of the organic solvent, and as a result, the surface tension of the treatment liquid in the meniscus decreases. As a result, a so-called Marangoni flow can be generated, in which the processing liquid on the substrate surface flows so as to be drawn into the processing liquid in the processing tank. The generation of the Marangoni flow affects the degree of liquid drainage of the processing liquid on the substrate surface, so that the time required for the solvent to evaporate and the sublimable substance to precipitate to form a solidified film is made shorter than the time required for the surface tension of the processing liquid to act on the pattern and cause the pattern to collapse. As a result, compared to conventional substrate processing methods, it is possible to form a solidified film while reducing or preventing the occurrence of pattern collapse.

[0014] In the above configuration, it is preferable that the boiling point of the solvent is lower than the boiling point of the organic solvent. This makes it easier for the solvent contained in the processing liquid to evaporate in the meniscus portion compared to the organic solvent after dissolution. As a result, the concentration of the organic solvent in the meniscus portion can be further increased, and the Marangoni flow in which the processing liquid on the substrate surface is drawn into the processing liquid in the processing tank side can be further increased. This further improves the drainage of the processing liquid on the substrate surface, so that a solidified film can be reliably formed before the surface tension of the processing liquid acts on the pattern and causes the pattern to collapse. Effect of the Invention

[0015] According to the present invention, when a plurality of substrates immersed in a processing liquid are pulled up at once, the process is performed under an atmosphere containing at least a vaporized gas obtained by vaporizing an organic solvent. In addition, an organic solvent that dissolves in the processing liquid and has a surface tension smaller than that of the solvent in the processing liquid is used, so that the vaporized gas of the organic solvent is dissolved in the meniscus portion where the processing liquid contacts the substrate surface, thereby reducing the surface tension of the processing liquid and generating a Marangoni flow. As a result, the processing liquid on the substrate surface is well drained, and a solidified film can be formed before the surface tension of the processing liquid acts on the pattern and collapses. Thus, in the present invention, a solidified film can be formed at once on a plurality of substrates by batch processing while reducing or preventing the occurrence of pattern collapse. As a result, the present invention can improve throughput compared to conventional substrate processing. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1(a) is an explanatory diagram showing the state before multiple substrates are immersed in a processing liquid or after they have been pulled out of a processing liquid in a substrate processing apparatus according to an embodiment of the present invention, and FIG. 1(b) is an explanatory diagram showing the state in which multiple substrates are immersed in the processing liquid. [Diagram 2] 2 is a cross-sectional view illustrating an outline of a processing tank of a solidified film forming unit in the substrate processing apparatus according to an embodiment of the present invention. FIG. [Diagram 3] 2 is a block diagram showing a schematic configuration of a processing liquid supply unit in the substrate processing apparatus according to the embodiment of the present invention. FIG. [Figure 4] 1 is a side view showing a schematic configuration of a holding unit and a lifting mechanism in a substrate processing apparatus according to an embodiment of the present invention. [Diagram 5] 2 is a block diagram showing a schematic configuration of a vaporized gas storage unit in the substrate processing apparatus according to an embodiment of the present invention. FIG. [Figure 6] FIG. 2 is an explanatory diagram showing a schematic configuration of a control unit in the substrate processing apparatus according to an embodiment of the present invention. [Figure 7]5A to 5C are explanatory views that diagrammatically show how a solidified film is formed on the surface of a substrate that has been pulled up from a processing liquid in a substrate processing method according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] (Substrate processing equipment) First, a substrate processing apparatus according to the present embodiment will be described below with reference to the drawings. The substrate processing apparatus according to the present embodiment is a batch-type substrate processing apparatus used for drying processing after cleaning processing, and can be used for processing various substrates, for example. Here, the term "substrate" refers to various substrates such as semiconductor substrates, glass substrates for photomasks, glass substrates for liquid crystal displays, glass substrates for plasma displays, substrates for FEDs (Field Emission Displays), substrates for optical disks, substrates for magnetic disks, and substrates for magneto-optical disks. The substrate processing apparatus according to the present embodiment is suitable for processing substrates having three-dimensional structures such as a three-dimensional NAND structure formed on the surface, for example.

[0018] 1(a) and 1(b), the substrate processing apparatus 1 of this embodiment specifically includes at least a solidified film forming section 10, a holding section (lifter) 20, a lifting mechanism 23, a vaporized gas supply section 30, a vaporized gas concentration detection section 40, an exhaust section 50, a control unit 60 that controls each section of the substrate processing apparatus 1, and a chamber 70. Fig. 1(a) is an explanatory diagram showing a state before a plurality of substrates W are immersed in a processing liquid or after they are lifted up from the processing liquid in the substrate processing apparatus 1 of this embodiment, and Fig. 1(b) is an explanatory diagram showing a state in which a plurality of substrates W are immersed in the processing liquid.

[0019] The solidified film forming unit 10 is a batch processing unit that collectively forms a solidified film containing a sublimable substance on the surfaces of multiple substrates W (hereinafter sometimes referred to as a "group of substrates W"). The solidified film is formed while drying the solvent of the processing liquid when the group of substrates W immersed in the processing liquid is removed from the processing liquid (details will be described later). The solidified film forming unit 10 includes a processing tank 11 and a processing liquid supply unit 12.

[0020] As shown in Fig. 2, the processing tank 11 includes an injection pipe 13 for supplying the processing liquid into the processing tank 11, an inner tank 14 for storing the processing liquid, and an outer tank 15 provided on the periphery of the upper opening of the inner tank 14. The injection pipe 13 is provided on the bottom of the processing tank 11, and enables the processing liquid to be supplied in an upflow manner to the inner tank 14. The inner tank 14 stores the processing liquid therein, thereby enabling the group of substrates W held in the holder 20 to be immersed in the processing liquid. The outer tank 15 enables the processing liquid overflowing from the inner tank 14 to be collected. Fig. 2 is a cross-sectional view showing an outline of the processing tank 11 of the solidified film forming unit 10 in the substrate processing apparatus 1 of this embodiment.

[0021] The processing liquid includes at least a sublimable substance and a solvent. The sublimable substance is preferably dissolved in the solvent in the processing liquid. The processing liquid serves to assist the drying process in the drying process for removing the liquid present on the surface of the substrate W. In this specification, "sublimability" means that a single substance, compound, or mixture has a property of undergoing phase transition from solid to gas or gas to solid without passing through a liquid state, and "sublimable substance" means a substance having such sublimability.

[0022] Sublimable substances include t-butanol, camphor, naphthalene, cyclohexane, cyclohexanol, cyclohexanone oxime, pinacoline oxime, and 4-tert-butylphenol.

[0023] The solvent is not particularly limited as long as it dissolves the sublimable substance, but it is preferable that the vapor pressure at 20°C is 500 Pa or more and 90 kPa or less (preferably 2000 Pa or more and 65 kPa or less, more preferably 4000 Pa or more and 30 kPa or less). By using a solvent with a vapor pressure of 500 Pa or more at 20°C, it is possible to promote evaporation of the solvent in the processing liquid on the pattern formation surface when the group of substrates W is pulled up together in an upright position (details will be described later). As a result, it is possible to form a solidified film before the surface tension of the processing liquid acts to cause the pattern to collapse.

[0024] The boiling point of the solvent is preferably in the range of 30°C or higher and 100°C or lower, more preferably in the range of 50°C or higher and 90°C or lower, and particularly preferably in the range of 65°C or higher and 85°C or lower.

[0025] More specifically, examples of the solvent include isopropyl alcohol (IPA), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether (PGEE), propylene glycol monomethyl ether (PGME), acetone, benzene, t-butanol, toluene, ethanol, methanol, etc. Among these solvents, in this embodiment, a solvent having a high vapor pressure such as IPA is preferable.

[0026] The concentration of the sublimable substance in the treatment liquid can be appropriately set according to need. The concentration of the sublimable substance is usually 0.2 mass% or more and 40 mass% or less, preferably 0.4 mass% or more and 11.4 mass% or less, more preferably 0.6 mass% or more and 4 mass% or less, based on the total mass of the treatment liquid.

[0027] The temperature of the processing liquid in the processing tank 11 is not particularly limited, but the lower limit is preferably higher than room temperature or the precipitation temperature at which the sublimable substance starts to precipitate in the processing liquid. The upper limit is preferably lower than the boiling point of the processing liquid or the solvent contained in the processing liquid. This makes it possible to suppress changes in the concentration of the processing liquid. If it is desired to increase the concentration of the solvent gas in the atmosphere at the lifting position of the group of substrates W, the processing liquid stored in the inner tank 14 may be heated to raise the temperature of the processing liquid above the boiling point of the solvent, thereby vaporizing the solvent.

[0028] The processing liquid supply unit 12 can supply a processing liquid to the processing tank 11. Specifically, as shown in Fig. 3, the processing liquid supply unit 12 at least includes a processing liquid storage unit 121, a temperature adjustment unit 122, a pressurization unit 123, a pipe 124, and a valve 125. Fig. 3 is a block diagram showing a schematic configuration of the processing liquid supply unit 12.

[0029] The treatment liquid storage section 121 can store the treatment liquid. The treatment liquid storage section 121 may be provided with an agitation section for agitating the treatment liquid stored therein. The agitation section is not particularly limited, and a known agitation section, such as one equipped with a propeller-shaped agitation blade or a circulation pump, can be used. When the agitation section is provided, the agitation section is electrically connected to the control unit 60. This allows the agitation section to agitate the treatment liquid in the treatment liquid storage section 121 based on an operation command from a control section (details of which will be described later) in the control unit 60. By agitating the treatment liquid, the concentration of the sublimable substance and the temperature of the treatment liquid can be made uniform.

[0030] The temperature adjustment unit 122 adjusts the temperature by heating the treatment liquid in the treatment liquid storage unit 121. By adjusting the temperature of the treatment liquid, for example, it is possible to prevent a sublimable substance from precipitating in the treatment liquid storage unit 121 and changing the concentration of the treatment liquid. In addition, the upper limit of the temperature adjustment of the treatment liquid is preferably a temperature lower than the boiling point of the treatment liquid or the solvent contained in the treatment liquid. The temperature adjustment unit 122 is electrically connected to the control unit 60, and adjusts the temperature of the treatment liquid based on an operation command from the control unit in the control unit 60. Specifically, the temperature adjustment unit 122 can be a known temperature adjustment mechanism such as a resistance heater, a Peltier element, or a pipe through which temperature-adjusted water flows. In addition, when a treatment liquid containing a solvent with a high vapor pressure is used, the solvent can be easily evaporated during the formation of a solidified film without heating the treatment liquid. When such a treatment liquid is used, the temperature adjustment unit 122 may be omitted.

[0031] The pressurizing unit 123 pressurizes the inside of the processing liquid storage unit 121, thereby pressure-feeding the processing liquid stored in the processing liquid storage unit 121 to the processing tank 11. The pressurizing unit 123 may, for example, include a gas tank for storing gas, a pump for pressurizing the gas, and a pipe for supplying the gas to the processing liquid storage unit 121. The gas tank is connected to the processing liquid storage unit 121 via the pipe. A pump is also inserted in the pipe. The pump is electrically connected to the control unit 60, and can supply the gas stored in the gas tank to the processing liquid storage unit 121 via the pipe in response to an operation command from the control unit in the control unit 60. This makes it possible to adjust the pressure in the processing liquid storage unit 121, thereby enabling pressure-feeding of the processing liquid to the processing tank 11. It is preferable to use an inert gas, such as nitrogen gas, that is not active against the processing liquid as the gas. In addition, since the processing liquid in the processing liquid storage section 121 is pumped using gas pressure, the processing liquid storage section 121 is preferably configured to be highly airtight.

[0032] One end of the pipe 124 is connected to the processing liquid storage section 121. The other end of the pipe 124 is connected to the injection pipe 13 of the processing tank 11 (see FIGS. 1(a) and 1(b)).

[0033] The valve 125 is provided midway along the path of the piping 124. The valve 125 is electrically connected to the control unit 60 and is normally closed. The opening and closing of the valve 125 is controlled by a control section in the control unit 60. For example, when the pump of the pressurizing section 123 supplies gas to the processing liquid storage section 121 and the valve 125 is opened in response to an operation command from the control section, the processing liquid in the pressurized processing liquid storage section 121 is pumped and supplied to the injection pipe 13 of the processing tank 11 via the piping 124.

[0034] As shown in FIG. 4, the holding part (lifter) 20 includes a flat back plate 21 and a plurality (three) of holding rods 22. The holding part 20 is a member configured to support a plurality of substrates W in an upright position by contacting them from below. FIG. 4 is a side view showing a schematic configuration of the holding part 20 and the lifting mechanism 23 in the substrate processing apparatus 1 of this embodiment. The back plate 21 stands upright, and at its lower end, the holding rods 22 extend in one direction so as to be perpendicular to the back plate 21. The holding rods 22 are provided with a plurality of grooves 24 arranged in the extending direction. The plurality of grooves 24 are arranged at equal intervals and spaced apart from each other. Furthermore, each groove 24 extends in a direction perpendicular to the extending direction of the holding rods 22, and can fit a plurality of substrates W in an upright position. As a result, the holding rods 22 can contact and support the group of substrates W from below in an upright position, thereby holding the group of substrates W collectively. The number of holding rods 22 is not particularly limited as long as there is more than one. The number of grooves 24 provided in the holding rods 22 is also not particularly limited, and may be set appropriately depending on the number of substrates W to be held. In this specification, the "upright position" refers to a position in which the surface (main surface, pattern-forming surface) of the substrate W is aligned approximately vertically to a horizontal plane, and includes the vertical position.

[0035] As shown in Fig. 4, the lifting mechanism 23 includes a connecting member 25, a lifting column 26, a ball screw 27, a lifting base 28, and a motor 29. The connecting member 25 extends from the upper end back surface of the back plate portion 21 in a direction perpendicular to the back plate portion 21 (parallel to the direction indicated by the arrow Y). The lifting column 26 is attached to the lower surface of the connecting member 25 at its upper end. The lifting column 26 is attached to the lifting base 28 at its lower end. The ball screw 27 is connected to a rotating shaft of the motor 29. The ball screw 27 is screwed into the lifting base 28 in a state where it penetrates the base. The motor 29 is electrically connected to a control unit 60.

[0036] The lifting mechanism 23 can raise or lower the holding part 20 in the X direction shown in Figs. 1(a), 1(b) and 4 in response to an operation command from the control part in the control unit 60. More specifically, when the motor 29 receives an operation command to raise from the control unit 60 and drives, the ball screw 27 rotates, and the lifting column 26 rises together with the lifting base 28. Accordingly, the back plate part 21 also rises via the connecting member 25 connected to the lifting column 26. Also, when the motor 29 receives an operation command to lower from the control unit 60 and drives in the reverse direction, the ball screw 27 rotates in the reverse direction, and the lifting column 26 descends together with the lifting base 28. Accordingly, the back plate part 21 also descends via the connecting member 25 connected to the lifting column 26. In this manner, by raising and lowering the back plate 21 while the group of substrates W is supported from below by the holding rods 22, the holding part 20 holding the group of substrates W collectively can be moved into or removed from the processing tank 11. More specifically, the lifting mechanism 23 raises and lowers the holding part 20 between a lifted position (retracted position) shown in FIG. 1(a) and a processing position shown in FIG. 1(b). In FIG. 1(a), the holding part 20 holding the group of substrates W is in a lifted position above the processing tank 11 so as not to be immersed in the processing liquid. In FIG. 1(b), the holding part 20 holding the group of substrates W is in a processing position in the processing tank 11 so as to be immersed in the processing liquid stored in the inner tank 14 of the processing tank 11. In this specification, the "lifted position (retracted position)" means a position above the processing tank 11 where at least the holding part 20 (substrates W) does not contact the liquid surface of the processing liquid. In addition, in this specification, the "processing position" refers to a position within the inner bath 14 of the processing bath 11 where the group of substrates W are completely immersed in the processing liquid.

[0037] The processing liquid temperature adjusting unit 16 can adjust the temperature of the processing liquid stored in the inner tank 14 of the processing tank 11. As shown in FIG. 1(a) and FIG. 1(b), the processing liquid temperature adjusting unit 16 is electrically connected to the control unit 60, and adjusts the temperature of the processing liquid stored in the processing tank 11 in response to an operation command from the control unit in the control unit 60. For example, when the group of substrates W is pulled up, the processing liquid stored in the inner tank 14 may be heated to vaporize the solvent contained in the processing liquid. This makes it possible to reduce the concentration of the solvent in the processing liquid. The processing liquid temperature adjusting unit 16 is not particularly limited, and any known temperature adjustment mechanism such as a Peltier element or a pipe through which temperature-adjusted water flows can be used.

[0038] The vaporization gas supply unit 30 is a unit that supplies a mixed gas containing a vaporized gas obtained by vaporizing an organic solvent into the chamber 70, and includes a vaporization gas storage unit 31 and a gas supply pipe 36. The vaporization gas supply unit 30 of the present embodiment can supply a mixed gas containing a vaporized gas of an organic solvent into the chamber 70. The mixed gas can contain an inert gas as a carrier gas in addition to the vaporization gas.

[0039] 5, the vaporized gas storage unit 31 includes an inert gas supply unit 32, an organic solvent supply unit 33, a vaporized gas generation unit 34, and a heating unit 35. FIG 5 is a block diagram showing a schematic configuration of the vaporized gas storage unit 31.

[0040] The inert gas supply unit 32 supplies an inert gas as a carrier gas. The inert gas supply unit 32 includes at least an inert gas supply source 32a for storing an inert gas, an inert gas supply pipe 32b, and a valve 32c. The inert gas supply source 32a is connected to a generation tank 34a (details of which will be described later) of the vaporized gas generation unit 34 via the inert gas supply pipe 32b. A bubbling nozzle for discharging the inert gas is provided at the end of the inert gas supply pipe 32b. The bubbling nozzle is preferably provided near the bottom of the generation tank 34a so as to be below the liquid level of the organic solvent stored in the generation tank 34a. The bubbling nozzle is preferably provided with a plurality of discharge ports for discharging the inert gas. Furthermore, the bubbling nozzle is preferably extended in a substantially horizontal direction relative to the bottom of the generation tank 34a.

[0041] The valve 32c is inserted into the inert gas supply pipe 32b. The valve 32c is electrically connected to the control unit 60 and is usually closed. The opening and closing of the valve 32c is controlled by a control unit in the control unit 60. When the valve 32c is opened by an operation command from the control unit, the inert gas stored in the inert gas supply source 32a is pressurized by a pressurizing means (not shown), and is supplied to the generation tank 34a through the inert gas supply pipe 32b. The inert gas is discharged from a bubbling nozzle provided at the end of the inert gas supply pipe 32b, and is supplied into the organic solvent by bubbling. The inert gas is not particularly limited as long as it is not active against the organic solvent, and for example, nitrogen or the like can be used.

[0042] The organic solvent supply unit 33 includes at least an organic solvent tank 33a for storing an organic solvent, a pipe 33b, and a valve 33c. The organic solvent tank 33a stores an organic solvent. The organic solvent tank 33a is connected to a production tank 34a of the vaporized gas production unit 34 through a pipe 33b. A valve 33c is inserted into the pipe 33b. The valve 33c is electrically connected to the control unit 60 and is usually closed. The opening and closing of the valve 33c is controlled by a control unit in the control unit 60. When the valve 33c is opened by an operation command from the control unit, the organic solvent stored in the organic solvent tank 33a is pressurized by a pressurizing means (not shown), and is thereby pressure-fed to the production tank 34a through the pipe 33b.

[0043] The organic solvent stored in the organic solvent tank 33a is one whose vaporized gas can be dissolved in the processing liquid. The organic solvent used has a surface tension smaller than that of the solvent used as a constituent of the processing liquid. By using such an organic solvent, the vaporized gas of the organic solvent is brought into contact with the processing liquid and dissolved therein, and when the vaporized gas of the organic solvent is dissolved in the processing liquid, the surface tension of the processing liquid can be reduced.

[0044] The surface tension of the organic solvent at 20°C is preferably in the range of 6 mN / m or more and 80 mN / m or less, more preferably in the range of 10 mN / m or more and 40 mN / m or less, and particularly preferably in the range of 20 mN / m or more and 30 mN / m or less.

[0045] In addition, the organic solvent preferably has a higher boiling point than the solvent used as a constituent of the treatment liquid. This allows the concentration of the organic solvent in the treatment liquid, in which the vaporized gas of the organic solvent is dissolved, to be relatively increased by evaporating the solvent contained in the treatment liquid. The boiling point of the organic solvent is preferably in the range of 30°C to 200°C, more preferably in the range of 50°C to 120°C, and particularly preferably in the range of 80°C to 105°C.

[0046] Specific examples of the organic solvent include IPA, 1-butanol, hydrofluoroether (HFE), PGMEA, and ethylene glycol.

[0047] The vaporization gas generation unit 34 includes at least a generation tank 34a for generating a mixed gas containing a vaporization gas, a pipe 34b, a valve 34c, and a pressurization unit (not shown). The generation tank 34a stores an organic solvent supplied from the organic solvent supply unit 33 therein, and generates a vaporization gas by heating with a heating unit 35. In addition, an inert gas is also supplied from the inert gas supply unit 32 to the generation tank 34a, so that a mixed gas containing the vaporization gas and the inert gas is generated in the generation tank 34a.

[0048] The pipe 34b is connected to the generation tank 34a at one end and to the gas supply pipe 36 at the other end.

[0049] The valve 34c is provided midway along the path of the pipe 34b. The valve 34c is electrically connected to the control unit 60 and is normally closed. The opening and closing of the valve 34c is controlled by the control section in the control unit 60. When the valve 34c is opened in response to an operation command from the control section in the control unit 60, the mixed gas generated in the production tank 34a is pressurized by the pressurizing section and sent to the gas supply pipe 36 through the pipe 34b. The pressurizing section is not particularly limited, and can be realized by pressurizing with a pump or the like, or by compressing and storing the mixed gas in the production tank 34a.

[0050] The concentration of the vaporized gas in the mixed gas is not particularly limited, and can be appropriately set depending on the concentration of the vaporized gas in the atmosphere at the position where the group of substrates W is pulled up, the supply amount of the mixed gas, and the like.

[0051] The heating unit 35 is electrically connected to the control unit 60, and heats the organic solvent stored in the production tank 34a in response to an operation command from the control unit in the control unit 60. Heating by the heating unit 35 may be performed, for example, so long as the temperature is equal to or higher than the boiling point of the organic solvent. This allows the generation of vaporized gas of the organic solvent in the production tank 34a. The heating unit 35 is not particularly limited, and may be any known temperature adjustment mechanism, such as a Peltier element or a pipe through which temperature-adjusted water or the like passes.

[0052] Vaporized gas concentration detection unit 40 can detect the concentration of vaporized gas in chamber 70. Vaporized gas concentration detection unit 40 includes at least a gas sensor 41. Gas sensor 41 detects vaporized gas as a target gas, and is disposed, for example, in a position that does not interfere with the raising and lowering of holding unit 20.

[0053] The vaporized gas concentration detection unit 40 is electrically connected to the control unit 60 and can transmit detection data relating to the vaporized gas concentration to the control unit 60 .

[0054] The vaporized gas concentration detection unit 40 may be provided at any number of different positions within the chamber 70. By measuring the vaporized gas concentration at each of the different positions, the uniformity of the vaporized gas concentration can be confirmed and evaluated. The detected concentration may be expressed as the average value of the concentrations measured at the multiple different positions. In this case, the average value can be calculated by an arithmetic average, a weighted average, or the like.

[0055] As shown in FIG. 1(a) and FIG. 1(b), the exhaust section 50 includes at least an exhaust pump 51, an exhaust pipe 52, and an exhaust valve 53 provided on the way of the exhaust pipe 52. The exhaust pump 51 is electrically connected to the control unit 60, so that the exhaust by the exhaust pump 51 can be controlled by an operation command from the control section. The exhaust valve 53 is electrically connected to the control section, so that the opening and closing of the exhaust valve 53 can be controlled by an operation command from the control section. When controlling the atmosphere in the chamber 70, the control section opens the valve 34c of the vaporization gas supply section 30. This causes a mixed gas containing the vaporization gas to be supplied into the chamber 70. The control section also operates the exhaust pump 51 and then opens the exhaust valve 53. This causes the exhaust pump 51 to exhaust the gas in the chamber 70 in addition to supplying the mixed gas into the chamber 70, so that the atmosphere in the chamber 70 contains the vaporization gas. As a result, it is possible to adjust the concentration of the vaporization gas in the atmosphere at the lifting position of the group of substrates W.

[0056] The control unit 60 is electrically connected to each part of the substrate processing apparatus 1 and controls the operation of each part. For example, as shown in Fig. 6, the control unit 60 has at least a control unit 61, a storage unit 62, and an input unit 63. Fig. 6 is an explanatory diagram showing a schematic configuration of the control unit 60 in the substrate processing apparatus 1 of the present embodiment.

[0057] The control unit 61 is not particularly limited, and may be, for example, a central processing unit (CPU) or a micro processing unit (MPU) for performing various arithmetic processing. The storage unit 62 includes a ROM, which is a read-only memory for storing a basic program, a RAM, which is a readable and writable memory for storing various information, and a magnetic disk for storing control software, data, and the like. The magnetic disk stores substrate processing conditions corresponding to the substrate W in advance. The magnetic disk also stores film forming conditions (details of which will be described later) corresponding to the processing liquid. The control unit 61 reads out a substrate processing program from the storage unit 62, and the control unit 61 controls each unit of the substrate processing apparatus 1 according to the contents of the program. The input unit 63 may be, for example, a keyboard or a mouse. Data input from the input unit 63 is accepted by the control unit 61, and may be stored in the storage unit 62 as necessary.

[0058] The control unit 61 controls the pump in the pressurizing unit 123 of the processing liquid supply unit 12 to adjust the pressure in the processing liquid storage unit 121 based on the substrate processing conditions read out from the memory unit 62. This pressure adjustment makes it possible to control the supply amount of the processing liquid pressure-fed from the processing liquid storage unit 121 to the processing tank 11. Furthermore, the control unit 61 controls the valve 125 in the processing liquid supply unit 12 to open and close based on the substrate processing conditions. This allows the control unit 61 to control the timing of supply of the processing liquid. Furthermore, when an agitation unit is provided in the processing liquid storage unit 121, the control unit 61 also controls the agitation unit based on the substrate processing conditions.

[0059] Furthermore, the control unit 61 controls the temperature adjustment unit 122 to adjust the temperature in the processing liquid storage unit 121 based on the substrate processing conditions read out from the memory unit 62. By this temperature adjustment, the temperature of the processing liquid pressure-fed from the processing liquid storage unit 121 to the processing tank 11 can be controlled.

[0060] Furthermore, the control unit 61 controls the processing liquid temperature adjusting unit 16 to adjust the temperature of the processing liquid stored in the inner tank 14 of the processing tank 11 based on the film formation conditions read out from the memory unit 62. By this temperature adjustment, the liquid temperature of the processing liquid stored in the inner tank 14 can be controlled.

[0061] Furthermore, the control unit 61 raises and lowers the holding unit 20 by controlling the raising and lowering operation of the lifting mechanism 23 based on the film formation conditions read out from the storage unit 62. The control unit 61 also controls the raising and lowering operation of the lifting mechanism 23 to control the speed at which the holding unit 20 rises based on the film formation conditions. This controls the lifting speed of the group of substrates W collectively held by the holding unit 20.

[0062] In this specification, the "pull-up speed" refers to the speed at which the surface of the substrate W separates from the surface of the processing liquid. Therefore, when the height of the processing liquid surface does not decrease but remains constant, the pull-up speed refers to the rising speed of the substrate W relative to the surface of the processing liquid. When the height of the processing liquid surface decreases, the pull-up speed is expressed as the sum of the rising speed of the substrate W relative to the surface of the processing liquid and the falling speed of the processing liquid surface.

[0063] The control unit 61 controls the vaporization gas supply unit 30 based on the film formation conditions read from the memory unit 62 and / or the value of the measured concentration of the vaporization gas measured by the vaporization gas concentration detection unit 40 to supply a mixed gas containing a vaporization gas of an organic solvent into the chamber 70. Specifically, the control unit 61 controls the valve 32c in the inert gas supply unit 32 of the vaporization gas supply unit 30 to open and close. The control unit 61 also controls the valve 33c in the organic solvent supply unit 33 to open and close. This causes the inert gas to be supplied from the inert gas supply source 32a to the production tank 34a, and also causes the organic solvent to be supplied from the organic solvent tank 33a to the production tank 34a. The control unit 61 controls the heating unit 35 based on the film formation conditions read from the memory unit 62 to heat the organic solvent stored in the production tank 34a to a temperature equal to or higher than its boiling point. The control unit 61 also controls the valve 34c to open and close. As a result, the organic solvent is evaporated in the generation tank 34a to generate a vaporized gas, which is then sent to the gas supply pipe 36 together with the inert gas.

[0064] Furthermore, the control unit 61 controls the exhaust unit 50 based on the film formation conditions read from the memory unit 62 and / or the measured concentration value of the vaporized gas measured by the vaporized gas concentration detection unit 40, thereby exhausting the gas and the like from within the chamber 70. Specifically, the control unit 61 operates the exhaust pump 51 of the exhaust unit 50, and further opens the exhaust valve 53. This causes the gas and the like from within the chamber 70 to be exhausted from the exhaust pipe 52.

[0065] Here, the film formation conditions stored in the memory unit 62 include conditions that specify the lifting speed of the group of substrates W so that a solidified film of a target thickness (hereinafter sometimes referred to as a "target film thickness") is formed according to the concentration of the vaporized gas of the organic solvent in the chamber 70. More specifically, the film formation conditions include the concentration of the vaporized gas in the chamber 70, the target film thickness of the solidified film to be formed, and the lifting speed of the substrates W, each of which is associated with the concentration of the vaporized gas.

[0066] In this embodiment, the film formation conditions including those that define the concentration of the vaporized gas of the organic solvent are used for the following reason. That is, as shown in Fig. 7, for example, when the substrate W is immersed in a processing liquid 82 containing a solvent with a high vapor pressure and then the substrate W is pulled up, the solvent contained in the processing liquid 82 evaporates from the surface of the substrate W at the same time as the substrate W is pulled up. Therefore, solutes such as a sublimable substance 83 are precipitated on the surface of the substrate W due to the evaporation of the solvent, and a solidified film 81 containing the sublimable substance 83 is formed. Fig. 7 is an explanatory diagram that shows a schematic view of the formation of the solidified film 81 on the surface of the substrate W pulled up from the processing liquid 82.

[0067] Here, the chamber 70 is under an atmosphere of a mixed gas containing a vaporized gas 84 of an organic solvent. The vaporized gas 84 dissolves in the processing liquid 82, so that the vaporized gas 84 is dissolved in at least the surface layer of the processing liquid 82. In addition, when the vaporized gas 84 is in the form of an organic solvent, its surface tension is smaller than that of the processing liquid 82, so that the surface tension of the surface layer of the processing liquid 82 where the vaporized gas 84 is dissolved is relatively lower than that of the other parts. Under such circumstances, when the substrate W is pulled up from the processing liquid 82, the surface tension of the meniscus part where the processing liquid 82 contacts the surface of the substrate W becomes smaller, and the surface tension becomes non-uniform. In general, when the surface tension of the liquid surface is non-uniform, a Marangoni flow occurs in which the liquid flows from a place with low surface tension to a place with high surface tension. In the present invention, the surface tension of the meniscus part decreases, so that the processing liquid on the substrate surface tries to flow so as to be drawn into the processing liquid 82 on the processing tank 11 side. This improves the drainage of the processing liquid 82 on the surface of the substrate W. When the drainage of the processing liquid 82 is improved, the time required from when the surface tension of the processing liquid 82 starts to act on the pattern until the solidified film 81 is formed can be shortened, and the solidified film 81 can be formed before the collapse of the pattern caused by the surface tension occurs. As a result, the solidified film 81 can be formed while reducing or preventing the collapse of the pattern caused by the surface tension of the processing liquid 82.

[0068] (Substrate processing method) Next, a substrate processing method using the substrate processing apparatus 1 of this embodiment will be described below.

[0069] The substrate processing method of the present embodiment includes at least an immersion step of immersing the group of substrates W collectively in a processing liquid, and a solidified film forming step of forming a solidified film on each surface of the group of substrates W.

[0070] The immersion step is a step of immersing the group of substrates W held by the holder 20 in the processing liquid stored in the processing bath 11. That is, first, the plurality of substrates W are held by the holder 20 in the retreat position shown in FIG. 1(a). At this time, the plurality of substrates W are held so as to be in an upright position with respect to a horizontal plane. When the control unit 61 receives a film formation instruction for a solidified film from the input unit 63, it reads out the film formation conditions from the storage unit 62. Furthermore, the control unit 61 operates the lifting mechanism 23 based on the film formation conditions, and lowers the holder 20 to the processing position shown in FIG. 1(b), that is, into the inner bath 14 of the processing bath 11. As a result, the group of substrates W held by the holder 20 in an upright position are immersed in the processing liquid all at once. The descent speed of the group of substrates W when the group of substrates W is immersed in the processing liquid is not particularly limited, but is preferably a constant speed. In addition, the immersion time for which the group of substrates W is immersed in the processing liquid is not particularly limited, and can be set appropriately depending on the type of processing liquid used, etc.

[0071] The solidified film forming process is a process of lifting up the group of substrates W immersed in the processing liquid stored in the processing tank 11 and forming a solidified film on the surface of each substrate W. In this solidified film forming process, the group of substrates W is lifted up in an atmosphere containing the vaporized gas of the organic solvent. That is, the control unit 61 opens the valve 34c of the vaporized gas supply unit 30 to supply a mixed gas containing the vaporized gas into the chamber 70. The control unit 61 also operates the exhaust pump 51 of the exhaust unit 50, and then opens the exhaust valve 53 to exhaust the gas in the chamber 70 with the exhaust pump 51. This creates an atmosphere containing the vaporized gas in the chamber 70.

[0072] The concentration of the vaporized gas in the chamber 70 can be controlled based on, for example, the measured concentration of the vaporized gas measured by the vaporized gas concentration detection unit 40. That is, the control unit 61 receives an output related to the measured concentration of the vaporized gas measured by the vaporized gas concentration detection unit 40 from the vaporized gas concentration detection unit 40. When the measured concentration of the vaporized gas measured by the vaporized gas concentration detection unit 40 is different from the set concentration of the vaporized gas in the film forming conditions read from the memory unit 62, the control unit 61 controls the opening and closing of the valve 34c of the vaporized gas supply unit 30, the operation of the exhaust pump 51 of the exhaust unit 50, and the opening and closing of the exhaust valve 53 based on the value of the measured concentration of the vaporized gas. This makes it possible to adjust the concentration of the vaporized gas in the chamber 70. For example, while the exhaust unit 50 exhausts the gas in the chamber 70, the vaporized gas supply unit 30 supplies a mixed gas containing the vaporized gas into the chamber 70. This creates an atmosphere containing a vaporized gas of a predetermined concentration in the chamber 70.

[0073] On the other hand, when the measured concentration of the vaporized gas measured by the vaporized gas concentration detection unit 40 is the same as the set concentration of the vaporized gas in the film formation conditions read out from the memory unit 62, the control unit 61 operates the lifting mechanism 23 based on the film formation conditions to raise the holding unit 20 to the retreat position shown in Fig. 1(a), i.e., above the inner bath 14 of the processing bath 11. As a result, the group of substrates W held by the holding unit 20 are lifted up collectively from the processing liquid.

[0074] The direction in which the group of substrates W are pulled up (the direction in which the holder 20 is raised) is not particularly limited, but is preferably a direction perpendicular to the liquid surface (horizontal surface) of the processing liquid 82.

[0075] When the group of substrates W is lifted up from the processing liquid, a solidified film 81 is formed on the surface of the group of substrates W at the time of lifting. That is, as shown in FIG. 7, when the substrates W are lifted up from the processing liquid 82, the solvent contained in the processing liquid 82 evaporates on the surface of the substrates W at the same time. As a result, on the surface of the substrates W, solutes such as sublimable substances 83 are precipitated due to the evaporation of the solvent, and a solidified film 81 containing the sublimable substances 83 is formed. In addition, in this embodiment, the chamber 70 is filled with an atmosphere containing a vaporized gas of an organic solvent, and the group of substrates W is lifted up under that atmosphere, so that the processing liquid 82 is well drained when the substrates W are lifted up due to the effect of the Marangoni flow described above. This allows the solidified film 81 to be formed before the surface tension of the processing liquid 82 acts on the pattern and causes the pattern to collapse. As a result, the solidified film 81 can be formed while suppressing or reducing the occurrence of pattern collapse.

[0076] In addition, when the boiling point of the solvent in the processing liquid 82 is lower than the boiling point of the organic solvent, the solidified film 81 may be formed while heating the processing liquid 82 in the inner bath 14 so that the temperature of the processing liquid 82 is in the range of the boiling point of the solvent or more and less than the boiling point of the organic solvent. As a result, the solvent contained in the processing liquid 82 evaporates in the meniscus portion, and the concentration of the organic solvent becomes relatively high. As a result, the Marangoni flow that tries to draw the processing liquid 82 on the surface of the substrate W into the processing liquid 82 on the processing bath 11 side becomes even stronger, and the drainage of the processing liquid 82 on the surface of the substrate W can be further improved. The processing liquid 82 in the processing bath 11 can be heated by the processing liquid temperature adjustment unit 16 based on an operation command from the control unit 61.

[0077] Here, the lifting speed of the group of substrates W may be determined by the control unit 60, for example, as follows. That is, when the vaporized gas concentration detection unit 40 measures the concentration of the vaporized gas in the chamber 70 and the input unit 63 inputs the target thickness of the solidified film to be formed, the control unit 61 reads out the film forming conditions from the storage unit 62. The read-out film forming conditions correspond to the relationship between the concentration of the vaporized gas, the target thickness of the solidified film, and the lifting speed of the substrates W. Furthermore, the control unit 61 determines the lifting speed of the group of substrates W by referring to the read-out film forming conditions based on the input target thickness of the solidified film and the measured concentration of the vaporized gas. Next, the control unit 61 issues an operation command to the lifting mechanism 23 based on the determined lifting speed, and executes the lifting of the group of substrates W by the holding unit 20.

[0078] The lifting speed of the group of substrates W may be constant from the start to the end of the lifting, or may be changed according to the lifting distance of the group of substrates W. When the lifting speed is constant, if there is no change over time in the physical properties (e.g., density, viscosity, etc.) of the processing liquid 82, the uniformity of the film thickness of the solidified film 81 can also be controlled with high precision. As a result, when the solidified film 81 is formed or when the solidified film 81 is sublimated, non-uniform application of stress to the pattern of the substrate W can be reduced, and the occurrence of pattern collapse can be further reduced.

[0079] It is preferable that the surface of the processing liquid 82 is stationary when the group of substrates W is pulled up. This makes it possible to form a constant meniscus on the surface of the processing liquid 82, which is formed by interaction with the surface of the substrate W, while the substrates W are being pulled up from the processing liquid 82, and therefore the cutting off of the processing liquid is also constant, making it possible to form a solidified film 81 with even more excellent uniformity in film thickness.

[0080] The substrates W are lifted up from the processing liquid 82 in an upright position. This method allows the deposited sublimable material 83 to grow in crystal in a plane, thereby forming the solidified film 81. That is, the deposited sublimable material 83 can be prevented from growing in crystal in three dimensions, which prevents film defects caused by grain boundary generation, and reduces or prevents pattern collapse. Furthermore, it is preferable that the upright position of the substrates W is constant while the substrates W are lifted up from the processing liquid 82. This allows the solidified film 81 to be formed with further improved film thickness uniformity. Furthermore, in the method of forming the solidified film 81 on the surface of the substrates W at the same time as the substrates W are lifted up from the processing liquid 82, the time during which the stress caused by the formation of the solidified film 81 is applied to the pattern on the surface of the substrates W can be shortened as much as possible. Particularly in the present invention, the Marangoni flow is generated when the substrates W are lifted up to improve the liquid cut-off of the processing liquid 82 on the surface of the substrates W, which shortens the time during which the surface tension of the processing liquid 82 acts on the pattern, thereby enabling the solidified film 81 to be formed before the pattern collapses. As a result, the occurrence of pattern collapse can be further reduced or prevented. Furthermore, in the formation of the solidified film 81 of this embodiment, the group of substrates W are immersed in the processing liquid 82 all at once, so that liquids and the like adhering to the surfaces of the respective substrates W can be substituted with the processing liquid 82 all at once for the group of substrates W. In particular, in a substrate having a three-dimensional structure such as a three-dimensional NAND structure, it takes a significant amount of time to substitute the liquid in a trench formed in a direction perpendicular to the surface of the substrate and an ON (oxide film-nitride film) structure extending horizontally from the trench. Therefore, if a plurality of substrates are processed one by one by single-wafer processing, it takes a long time. However, in the substrate processing method of this embodiment, the plurality of substrates W are immersed in the processing liquid 82 all at once, so that the plurality of substrates W having such a three-dimensional structure can be substituted with the processing liquid 82 all at once. Therefore, the processing can be performed in an extremely short time compared to the case where a plurality of substrates W are processed one by one by single-wafer processing. Furthermore, the amount of processing liquid used can be reduced compared to the case where the processing liquid is substituted by the single-wafer method.

[0081] When the group of substrates W are collectively lifted out of the processing liquid 82 and the holder 20 returns to the retreat position, the solidified film forming process is completed.

[0082] As described above, in the substrate processing method of the present embodiment, a plurality of substrates W are immersed in the processing liquid 82 all at once, and then the solidified film 81 is formed while the substrates W are being pulled out of the processing liquid 82 all at once. When the substrates W are pulled out, the chamber 70 is placed under an atmosphere containing the vaporized gas of the organic solvent, so that a Marangoni flow is generated when the substrates W are pulled out, and the processing liquid 82 is smoothly drained. As a result, in the present embodiment, the solidified film 81 can be formed before the surface tension of the processing liquid 82 acts on the pattern and causes the pattern to collapse. Therefore, compared to the case where a solidified film is formed on the surface of a substrate by a single-wafer processing method in which the substrates are processed one by one, the substrate processing can be performed while reducing or preventing the collapse of the pattern. [Explanation of symbols]

[0083] 1...substrate processing apparatus, 10...solidified film forming section, 11...processing tank, 12...processing liquid supply section, 13...injection tube, 14...inner tank, 15...outer tank, 16...processing liquid temperature adjustment section, 20...holding section, 21...back plate section, 22...holding rod, 23...lifting mechanism, 24...groove section, 25...connecting member, 26...lifting support column, 27...ball screw, 28...lifting base, 29...motor, 30...vaporized gas supply section, 31...vaporized gas storage section, 32...inert gas supply section, 32a...inert gas supply source, 32b...inert gas supply pipe, 32c...valve, 33...organic solvent Supply section, 33a...organic solvent tank, 33b...piping, 33c...valve, 34...vaporized gas generation section, 34a...generation tank, 34b...piping, 34c...valve, 35...heating section, 36...gas supply pipe, 40...vaporized gas concentration detection section, 41...gas sensor, 50...exhaust section, 51...exhaust pump, 52...exhaust pipe, 53...exhaust valve, 60...control unit, 61...control section, 62...storage section, 63...input section, 70...chamber, 121...processing liquid storage section, 122...temperature adjustment section, 123...pressurization section, 124...piping, 125...valve

Claims

1. A substrate processing apparatus for processing a surface of a substrate, comprising: A chamber; a processing tank accommodated in the chamber and configured to store a processing liquid including a sublimable material and a solvent; a holding section for collectively holding the plurality of substrates in an upright position; a lifting mechanism that lifts and lowers the holding unit relative to the treatment tank to immerse the holding unit in the treatment liquid or remove the holding unit from the treatment liquid; a vaporization gas supply unit that supplies at least a vaporization gas obtained by vaporizing an organic solvent into the chamber; Equipped with The immersion and removal are performed by: a process for forming a solidified film containing the sublimable substance on a surface of the substrate by evaporating the solvent while simultaneously lifting up the substrates immersed in the processing liquid, The vaporized gas dissolves in the processing liquid, and the organic solvent has a surface tension smaller than that of the solvent.

2. The substrate processing apparatus according to claim 1 , wherein the solvent has a boiling point lower than a boiling point of the organic solvent.

3. The substrate processing apparatus according to claim 1 , further comprising an exhaust unit that exhausts gas from within the chamber to the outside.

4. The substrate processing apparatus according to claim 1 , further comprising a vaporized gas concentration detector for detecting a concentration of the vaporized gas in the chamber.

5. A substrate processing method for processing a surface of a substrate, comprising the steps of: an immersion step of immersing a plurality of the substrates collectively in a treatment liquid containing a sublimable substance and a solvent and stored in a treatment tank; a solidified film forming step of evaporating the solvent while simultaneously lifting up the plurality of substrates in an upright position to cause the sublimable substance to precipitate, thereby forming a solidified film containing the sublimable substance on the pattern forming surface; Including, The solidified film forming step is carried out in a chamber under an atmosphere containing at least a vaporized gas obtained by vaporizing an organic solvent, The substrate processing method, wherein the vaporized gas dissolves in the processing liquid, and the organic solvent has a surface tension smaller than that of the solvent.

6. The substrate processing method according to claim 5 , wherein the boiling point of the solvent is lower than the boiling point of the organic solvent.

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