Substrate processing method, substrate processing apparatus, and drying processing liquid

Abstract

To suppress collapse of a pattern during drying processing.SOLUTION: A substrate processing method includes a step of supplying a chemical solution to the surface of a substrate (step S11), a step of supplying a rinse liquid to the surface of the substrate after the step S11 (step S12), a step of contacting the surface of the substrate with a heated drying treatment liquid after the step S12 (step S14), and a step of drying the substrate by removing the drying treatment liquid from the surface of the substrate after the step S14 (step S15). The surface tension of the drying treatment liquid is lower than that of the rinse liquid. The boiling point of the drying treatment liquid is higher than the boiling point of the rinse liquid. The temperature of the dry treatment liquid that contacts the surface of the substrate in the step S14 is a predetermined contact temperature that is equal to or higher than the boiling point of the rinsing liquid and less than the boiling point of the dry treatment liquid. As a result, it is possible to prevent the pattern from collapsing during the drying process.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to techniques for processing substrates and to dry processing liquids used in processing substrates. [Background technology]

[0002] Conventionally, in the manufacturing process of semiconductor substrates (hereinafter simply referred to as "substrates"), various processes are performed on the substrates. For example, a chemical solution such as an etching solution is supplied to the surface of the substrate to perform chemical processing. After the chemical processing is completed, a rinse solution is supplied to the substrate to perform a rinse process, and then the substrate is dried.

[0003] When a fine pattern is formed on the surface of a substrate, the surface tension of the liquid acts at the contact point between the pattern and the liquid surface (i.e., the interface between the liquid and air).Water, which is typically used as the rinse liquid, has a high surface tension, so there is a risk that the pattern will collapse during the drying process after the rinse process.

[0004] Therefore, Patent Document 1 discloses a technique in which, in order to prevent pattern collapse, IPA (isopropyl alcohol), which has a surface tension lower than that of water, is supplied onto the substrate after rinsing to replace the water, and then the IPA is removed from the substrate to perform a drying process on the substrate. Patent Document 1 also lists HFE (hydrofluoroether), methanol, ethanol, and the like, which have a surface tension lower than that of water, as liquids that can be used instead of IPA.

[0005] Furthermore, Patent Document 2 discloses a technique for preventing pattern collapse by supplying IPA onto a substrate after rinsing to replace water, supplying a hydrophobizing agent onto the substrate to hydrophobize the upper surface of the substrate, and then supplying IPA onto the substrate to replace the hydrophobizing agent, and then removing the IPA from the substrate to perform a drying process on the substrate. Patent Document 2 also lists HFE, HFC (hydrofluorocarbon), methanol, ethanol, and the like, which have a surface tension lower than that of water, as liquids that can be used instead of IPA. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-117954 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-157625 Summary of the Invention [Problem to be solved by the invention]

[0007] In recent years, as the aspect ratio of patterns on substrates has increased, patterns have become more susceptible to collapse, and there is a demand for further suppression of pattern collapse during drying treatment.

[0008] The present invention has been made in view of the above-mentioned problems, and has as its object to prevent pattern collapse during drying processing. [Means for solving the problem]

[0009] The invention described in claim 1 is a substrate processing method for processing a substrate, comprising: a) a step of supplying a chemical liquid to a surface of the substrate; b) a step of supplying a rinse liquid to the surface of the substrate after the step a); c) a step of contacting a heated drying treatment liquid with the surface of the substrate after the step b); and d) a step of drying the substrate by removing the drying treatment liquid from the surface of the substrate after the step c), wherein the surface tension of the drying treatment liquid is lower than the surface tension of the rinse liquid, the boiling point of the drying treatment liquid is higher than the boiling point of the rinse liquid, and the temperature of the drying treatment liquid that contacts the surface of the substrate in the step c) is a predetermined contact temperature that is equal to or higher than the boiling point of the rinse liquid and lower than the boiling point of the drying treatment liquid. In the step c), the drying treatment liquid is heated after contacting the surface of the substrate, thereby raising the temperature of the drying treatment liquid to the contact temperature.

[0010] The invention described in claim 2 is the substrate processing method described in claim 1, further comprising the step of: e) removing molecules of the drying processing liquid adsorbed on the surface of the substrate by heating the substrate after step d).

[0011] A third aspect of the present invention is the substrate processing method according to the second aspect, wherein the step d) and the step e) are performed in the same chamber.

[0012] The invention of claim 4 is the substrate processing method of any one of claims 1 to 3, further comprising a step of supplying a replacement liquid to the surface of the substrate between step b) and step c) to replace the rinse liquid in contact with the surface of the substrate with the replacement liquid, and in step c), the replacement liquid in contact with the surface of the substrate is replaced with the drying processing liquid.

[0015] Claim 5 The invention described in claims 1 to 4 2. The substrate processing method according to claim 1, wherein a difference between the contact temperature and the boiling point of the drying processing liquid is 65° C. or less.

[0016] Claim 6 The invention described in claims 1 to 5 In the step c), the contact time of the drying processing liquid at the contact temperature with the surface of the substrate is 10 seconds or more.

[0017] Claim 7 The invention described in claims 1 to 6 2. The substrate processing method according to claim 1, wherein the drying processing liquid contains a fluorine-containing alcohol.

[0018] Claim 8 The invention described in claim 7 2. The substrate processing method according to claim 1, wherein the fluorine-containing alcohol has a —CF 2 H group at its terminal end.

[0019] Claim 9 The invention described in claim 7 2. The substrate processing method according to claim 1, wherein the fluorine-containing alcohol has —CF 3 at its end.

[0020] Claim 10 The invention described in claim 7 Or 9 In the substrate processing method according to any one of the above, the number of C's contained in the molecular formula of the fluorine-containing alcohol is 4 or more.

[0021] Claim 11 The invention described in is a substrate processing apparatus for processing a substrate, the substrate processing apparatus including a chemical liquid supply unit that supplies a chemical liquid to a surface of a substrate, a rinse liquid supply unit that supplies a rinse liquid to the surface of the substrate, a drying liquid supply unit that supplies a heated drying liquid to the surface of the substrate, and a drying processing unit that dries the substrate by removing the drying liquid from the surface of the substrate. a substrate heating unit that heats the substrate; wherein the surface tension of the drying treatment liquid is lower than the surface tension of the rinsing liquid, the boiling point of the drying treatment liquid is higher than the boiling point of the rinsing liquid, and the temperature of the drying treatment liquid in contact with the surface of the substrate is a predetermined contact temperature that is equal to or higher than the boiling point of the rinsing liquid and lower than the boiling point of the drying treatment liquid. The drying treatment liquid after contacting the surface of the substrate is heated by the substrate heating unit, thereby raising the temperature of the drying treatment liquid to the contact temperature.

[0022] Claim 12 The invention described in claim 11 2. The substrate processing apparatus according to claim 1, wherein the drying processing liquid contains a fluorine-containing alcohol.

[0023] Claim 13The invention described in is a drying treatment liquid used for treating a substrate, and a substrate treatment method using the drying treatment liquid comprises: a) a step of supplying a chemical liquid to a surface of a substrate; b) a step of supplying a rinse liquid to the surface of the substrate after the step a); c) a step of contacting the surface of the substrate with the heated drying treatment liquid after the step b); and d) a step of drying the substrate by removing the drying treatment liquid from the surface of the substrate after the step c), wherein the drying treatment liquid contains a fluorine-containing alcohol, the surface tension of the drying treatment liquid is lower than that of the rinse liquid, the boiling point of the drying treatment liquid is higher than that of the rinse liquid, and the temperature of the drying treatment liquid that comes into contact with the surface of the substrate in the step c) is a predetermined contact temperature that is equal to or higher than the boiling point of the rinse liquid and lower than the boiling point of the drying treatment liquid. In the step c), the drying treatment liquid is heated after contacting the surface of the substrate, thereby raising the temperature of the drying treatment liquid to the contact temperature. [Effects of the Invention]

[0024] In the present invention, it is possible to prevent the pattern from collapsing during the drying process. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a plan view showing a substrate processing system according to a first embodiment. [Figure 2] FIG. 2 is a side view showing the configuration of the substrate processing apparatus. [Figure 3] FIG. 2 is a diagram illustrating a configuration of a control unit. [Figure 4] FIG. 2 is a block diagram showing a gas-liquid supply unit. [Figure 5] FIG. 1 is a diagram showing a flow of substrate processing. [Figure 6A] FIG. 3 is a diagram schematically illustrating molecules of a first drying treatment liquid adsorbed onto a substrate. [Figure 6B] FIG. 10 is a diagram schematically illustrating molecules of a second drying treatment liquid adsorbed onto a substrate. [Figure 6C] FIG. 10 is a diagram schematically illustrating molecules of a third drying treatment liquid adsorbed onto a substrate. [Figure 7] FIG. 10 is a diagram showing the pattern collapse rate. [Figure 8]FIG. 10 is a diagram showing the pattern collapse rate. [Figure 9] FIG. 10 is a plan view showing a substrate processing system according to a second embodiment. [Figure 10] FIG. 4 is a side view showing the first processing section and a lifter. DETAILED DESCRIPTION OF THE INVENTION

[0026] 1 is a schematic plan view showing the layout of a substrate processing system 10 including a substrate processing apparatus according to a first embodiment of the present invention. The substrate processing system 10 processes semiconductor substrates 9 (hereinafter simply referred to as "substrates 9"). The substrate processing system 10 includes an indexer block 101 and a processing block 102 coupled to the indexer block 101.

[0027] The indexer block 101 includes a carrier holding unit 104, an indexer robot 105 (i.e., substrate transport means), and an IR movement mechanism 106. The carrier holding unit 104 holds a plurality of carriers 107, each capable of accommodating a plurality of substrates 9. The plurality of carriers 107 (e.g., FOUPs) are held by the carrier holding unit 104 while being arranged in a horizontal carrier arrangement direction (i.e., the up-and-down direction in FIG. 1). The IR movement mechanism 106 moves the indexer robot 105 in the carrier arrangement direction. The indexer robot 105 performs an unloading operation to unload the substrates 9 from the carriers 107, and a loading operation to load the substrates 9 into the carriers 107 held by the carrier holding unit 104. The substrates 9 are transported by the indexer robot 105 in a horizontal position.

[0028] On the other hand, the processing block 102 includes a plurality of (e.g., four or more) processing units 108 that process the substrates 9, and a center robot 109 (i.e., substrate transport means). The plurality of processing units 108 are arranged to surround the center robot 109 in a plan view. The plurality of processing units 108 perform various processes on the substrates 9. A substrate processing apparatus, which will be described later, is one of the plurality of processing units 108. The center robot 109 performs a load operation to load the substrates 9 into the processing units 108 and an unload operation to unload the substrates 9 from the processing units 108. Furthermore, the center robot 109 transports the substrates 9 between the plurality of processing units 108. The substrates 9 are transported in a horizontal position by the center robot 109. The center robot 109 receives the substrates 9 from the indexer robot 105 and passes the substrates 9 to the indexer robot 105.

[0029] Fig. 2 is a side view showing the configuration of the substrate processing apparatus 1. The substrate processing apparatus 1 is a single-wafer type apparatus that processes substrates 9 one by one. The substrate processing apparatus 1 performs liquid processing by supplying a processing liquid to the substrates 9. Fig. 2 shows a cross section of part of the configuration of the substrate processing apparatus 1.

[0030] The substrate processing apparatus 1 includes a substrate holding unit 31, a substrate rotation mechanism 33, a gas / liquid supply unit 5, a blocking unit 6, a substrate heating unit 7, a control unit 8, and a chamber 11. The substrate holding unit 31, the substrate rotation mechanism 33, the blocking unit 6, the substrate heating unit 7, etc. are housed in the internal space of the chamber 11. An airflow forming unit 12 is provided in the canopy of the chamber 11, and supplies gas to the internal space to form an airflow that flows downward (so-called downflow). For example, an FFU (fan filter unit) is used as the airflow forming unit 12.

[0031] The control unit 8 is disposed outside the chamber 11 and controls the substrate holder 31, the substrate rotation mechanism 33, the gas / liquid supply unit 5, the interrupter 6, the substrate heater 7, and the like. As shown in FIG. 3 , the control unit 8 is, for example, a typical computer system including a processor 81, a memory 82, an input / output unit 83, and a bus 84. The bus 84 is a signal circuit connecting the processor 81, the memory 82, and the input / output unit 83. The memory 82 stores programs and various information. The processor 81 executes various processes (e.g., numerical calculations) using the memory 82 and the like in accordance with the programs and the like stored in the memory 82. The input / output unit 83 includes a keyboard 85 and a mouse 86 for receiving input from an operator, a display 87 for displaying output from the processor 81, and a transmitter for transmitting output from the processor 81. The control unit 8 may be a programmable logic controller (PLC), a circuit board, or the like. The control unit 8 may include any combination of a computer system, a PLC, a circuit board, and the like.

[0032] The substrate holding unit 31 and substrate rotation mechanism 33 shown in FIG. 2 are each part of a spin chuck that holds and rotates the substrate 9. The substrate holding unit 31 faces the lower main surface (hereinafter also referred to as the "lower surface 92") of the horizontally positioned substrate 9 and holds the substrate 9 from below. The substrate holding unit 31 is, for example, a mechanical chuck that mechanically supports the substrate 9. The substrate holding unit 31 includes a base unit 311 and a plurality of chucks 312. The base unit 311 is a substantially disk-shaped member centered on a central axis J1 that faces the up-down direction. The substrate 9 is disposed above the base unit 311. The diameter of the base unit 311 is slightly larger than the diameter of the substrate 9.

[0033] The multiple chucks 312 are arranged on the outer periphery of the upper surface of the base portion 311 in a circumferential direction (hereinafter simply referred to as the "circumferential direction") centered on the central axis J1. The multiple chucks 312 are arranged, for example, at approximately equal angular intervals in the circumferential direction. In the substrate holding portion 31, the multiple chucks 312 hold the outer edge of the substrate 9. Note that the substrate holding portion 31 may be a chuck with another structure, such as a vacuum chuck that holds the center of the lower surface 92 of the substrate 9 by suction.

[0034] The substrate rotation mechanism 33 is disposed below the substrate holding part 31. The substrate rotation mechanism 33 rotates the substrate 9 together with the substrate holding part 31 around the central axis J1. The substrate rotation mechanism 33 includes a shaft 331 and a motor 332. The shaft 331 is a substantially cylindrical member centered on the central axis J1. The shaft 331 extends in the vertical direction and is connected to the center of the lower surface of the base part 311 of the substrate holding part 31. The motor 332 is an electric rotary motor that rotates the shaft 331. The substrate rotation mechanism 33 may be a motor having another structure (for example, a hollow motor, etc.).

[0035] The gas / liquid supply unit 5 individually supplies a plurality of types of processing liquids to the substrate 9 to perform liquid processing on the substrate 9. The gas / liquid supply unit 5 also supplies an inert gas toward the substrate 9. The plurality of types of processing liquids include a chemical liquid, a rinse liquid, a replacement liquid, and a drying processing liquid, which will be described later.

[0036] The gas / liquid supply unit 5 includes a first nozzle 51, a second nozzle 52, a third nozzle 53, and a fourth nozzle 54. The first nozzle 51, the second nozzle 52, the third nozzle 53, and the fourth nozzle 54 each eject a different type of processing liquid from above the substrate 9 toward the upper main surface (hereinafter also referred to as the "upper surface 91") of the substrate 9. A fine pattern is formed in advance on the upper surface 91 of the substrate 9. The pattern is, for example, a pattern having a high aspect ratio. The first nozzle 51, the second nozzle 52, the third nozzle 53, and the fourth nozzle 54 are formed, for example, from a resin having high chemical resistance, such as Teflon (registered trademark).

[0037] In the gas / liquid supply unit 5, two or more of the first nozzle 51, the second nozzle 52, the third nozzle 53, and the fourth nozzle 54 may be combined into one shared nozzle. In this case, the shared nozzle functions as each of the two or more nozzles. Within the shared nozzle, individual flow paths may be provided for each type of treatment liquid, or a shared flow path through which multiple types of treatment liquid flow may be provided. Furthermore, each of the first nozzle 51, the second nozzle 52, the third nozzle 53, and the fourth nozzle 54 may be configured by two or more nozzles.

[0038] The gas / liquid supply unit 5 further includes a first nozzle movement mechanism 511, a second nozzle movement mechanism 521, a third nozzle movement mechanism 531, and a fourth nozzle movement mechanism 541. The first nozzle movement mechanism 511 moves the first nozzle 51 approximately horizontally between a supply position above the substrate 9 and a retracted position located outside the outer edge of the substrate 9 in a radial direction (hereinafter simply referred to as the "radial direction") centered on the central axis J1. The second nozzle movement mechanism 521 moves the second nozzle 52 approximately horizontally between a supply position above the substrate 9 and a retracted position located outside the outer edge of the substrate 9 in the radial direction. The third nozzle movement mechanism 531 moves the third nozzle 53 approximately horizontally between a supply position above the substrate 9 and a retracted position located outside the outer edge of the substrate 9 in the radial direction. The fourth nozzle movement mechanism 541 moves the fourth nozzle 54 approximately horizontally between a supply position above the substrate 9 and a retracted position located outside the outer edge of the substrate 9 in the radial direction. The first nozzle moving mechanism 511 includes, for example, an electric linear motor, an air cylinder, or a ball screw and an electric rotary motor connected to the first nozzle 51. The same applies to the second nozzle moving mechanism 521, the third nozzle moving mechanism 531, and the fourth nozzle moving mechanism 541.

[0039] The blocking unit 6 includes a top plate 61, a top plate rotation mechanism 62, and a top plate movement mechanism 63. The top plate 61 is a substantially disk-shaped member centered on a central axis J1, and is disposed above the substrate holding unit 31. The diameter of the top plate 61 is slightly larger than the diameter of the substrate 9. The top plate 61 is an opposing member that faces the upper surface 91 of the substrate 9, and is a shielding plate that shields the space above the substrate 9.

[0040] The top plate rotation mechanism 62 is disposed above the top plate 61. The top plate rotation mechanism 62 rotates the top plate 61 about a central axis J1. The top plate rotation mechanism 62 includes a shaft 621 and a motor 622. The shaft 621 is a substantially cylindrical member centered on the central axis J1. The shaft 621 extends in the vertical direction and is connected to the center of the upper surface of the top plate 61. The motor 622 is an electric rotary motor that rotates the shaft 621. The top plate rotation mechanism 62 may be a motor having another structure (for example, a hollow motor, etc.).

[0041] The top plate moving mechanism 63 moves the top plate 61 in the vertical direction above the substrate 9. The top plate moving mechanism 63 includes, for example, an electric linear motor connected to the shaft 621, an air cylinder, or a ball screw and an electric rotary motor.

[0042] The substrate heating unit 7 includes a light irradiator 71 that irradiates light onto the substrate 9 to heat it. In the example shown in FIG. 1 , the light irradiator 71 is provided on the top plate 61 and heats the substrate 9 by irradiating light from the underside of the top plate 61 toward the upper surface 91 of the substrate 9. The light irradiator 71 includes, for example, a plurality of LEDs (Light Emitting Diodes) built into the underside of the top plate 61. The plurality of LEDs are, for example, arranged approximately evenly in an approximately annular region centered on the central axis J1 on the underside of the top plate 61, and irradiate light onto the entire upper surface 91 of the substrate 9. The light irradiator 71 may be provided separately from the top plate 61 and irradiate light onto the upper surface 91 of the substrate 9. Alternatively, the light irradiator 71 may heat the substrate 9 by irradiating light onto the lower surface 92 of the substrate 9. In this case, the light irradiator 71 may be provided on the base portion 311 of the substrate holding unit 31. Substrate heating section 7 may heat substrate 9 by a method other than light irradiation (for example, an electric heating wire heater or supply of a heated fluid).

[0043] The gas / liquid supply unit 5 further includes an upper nozzle 55 and a lower nozzle 56. The upper nozzle 55 is disposed inside a shaft 621 of the top plate rotation mechanism 62. The lower end of the upper nozzle 55 protrudes downward from an opening provided in the center of the top plate 61 and faces the center of the upper surface 91 of the substrate 9 in the vertical direction. The upper nozzle 55 supplies an inert gas toward the upper surface 91 of the substrate 9. The lower nozzle 56 is disposed inside a shaft 331 of the substrate rotation mechanism 33. The upper end of the lower nozzle 56 protrudes upward from an opening provided in the center of the base portion 311 of the substrate holder 31 and faces the center of the lower surface 92 of the substrate 9 in the vertical direction. The lower nozzle 56 supplies a processing liquid toward the lower surface 92 of the substrate 9 when liquid processing of the lower surface 92 of the substrate 9 is required. Alternatively, the lower nozzle 56 may be used to supply a gas (e.g., a heated inert gas) to the lower surface 92 of the substrate 9.

[0044] FIG. 4 is a block diagram showing the gas / liquid supply unit 5 of the substrate processing apparatus 1. The first nozzle 51 is connected to a chemical supply source 512 via a pipe 513 and a valve 514. When the valve 514 is opened under the control of the control unit 8 (see FIG. 2), the chemical used for chemical processing of the substrate 9 is ejected from the tip of the first nozzle 51 onto the upper surface 91 of the substrate 9. That is, the first nozzle 51 is a chemical supply unit that supplies the chemical to the substrate 9. The chemical is, for example, hydrofluoric acid. The chemical may be a liquid other than hydrofluoric acid. The chemical may be, for example, a liquid containing at least one of sulfuric acid, acetic acid, nitric acid, hydrochloric acid, hydrofluoric acid, ammonia water, hydrogen peroxide water, an organic acid (e.g., citric acid, oxalic acid, etc.), an organic alkali (e.g., TMAH: tetramethylammonium hydroxide, etc.), a surfactant, and a corrosion inhibitor.

[0045] The second nozzle 52 is connected to a rinse liquid supply source 522 via a pipe 523 and a valve 524. When the valve 524 is opened under the control of the control unit 8, the rinse liquid used for rinsing the substrate 9 is ejected from the tip of the second nozzle 52 onto the upper surface 91 of the substrate 9. In other words, the second nozzle 52 is a rinse liquid supply unit that supplies the rinse liquid to the substrate 9. The rinse liquid is, for example, DIW (de-ionized water). The rinse liquid may be a liquid other than DIW. The rinse liquid may be, for example, carbonated water, electrolytic ionized water, hydrogen water, ozone water, or hydrochloric acid water with a diluted concentration of approximately 10 ppm to 100 ppm.

[0046] The third nozzle 53 is connected to a substitute liquid supply source 532 via a pipe 533 and a valve 534. When the valve 534 is opened under the control of the control unit 8, the substitute liquid used in the replacement process for the rinse liquid is ejected from the tip of the third nozzle 53 onto the upper surface 91 of the substrate 9. In other words, the third nozzle 53 is a substitute liquid supply unit that supplies the substitute liquid to the substrate 9. The replacement process is a process in which the substitute liquid is supplied to the substrate 9 to replace the rinse liquid on the substrate 9 with the substitute liquid. As the substitute liquid, a liquid that has a relatively high affinity with the rinse liquid and also a relatively high affinity with the drying process liquid described below is used. The substitute liquid is, for example, IPA (isopropyl alcohol). The substitute liquid may be a liquid other than IPA. The substitute liquid may be, for example, methanol, ethanol, or the like.

[0047] The fourth nozzle 54 is connected to a drying treatment liquid supply source 542 via a pipe 543, a valve 544, and a liquid heating unit 545. The liquid heating unit 545 preheats the drying treatment liquid used in the drying treatment of the substrate 9 as needed. The liquid heating unit 545 is, for example, an electric wire heater. When the valve 544 is opened under the control of the control unit 8, the heated drying treatment liquid is ejected from the tip of the fourth nozzle 54 onto the upper surface 91 of the substrate 9. In other words, the fourth nozzle 54 is a drying treatment liquid supply unit that supplies the heated drying treatment liquid to the substrate 9 and brings it into contact with the substrate 9.

[0048] The drying treatment liquid preferably contains a fluorine-containing alcohol. The fluorine-containing alcohol is, for example, a fluorine-containing alcohol having a terminal group of "-CF2H (difluoromethyl group)" or "-CF3 (trifluoromethyl group)." The terminal group refers to the end of the fluorine-containing alcohol molecule opposite to the "-OH (hydroxy group)" of the fluorinated alkyl chain. When the fluorinated alkyl chain is branched, the terminal group may be the end of the main chain or the end of a branch chain. The surface tension of the drying treatment liquid is lower than that of the above-mentioned rinse liquid. The boiling point of the drying treatment liquid is higher than that of the rinse liquid. The drying treatment liquid is a liquid that does not chemically react with the surface of the substrate 9 and the pattern formed on the substrate 9. The number of C atoms in the molecular formula of the fluorine-containing alcohol is preferably 3 or more, more preferably 4 or more. The number of C atoms in the molecular formula of the fluorine-containing alcohol is preferably 8 or less, more preferably 7 or less. By limiting the number of Cs to 7 or less, it is possible to avoid being subject to PFOA (perfluorooctanoic acid) regulations.

[0049] The drying treatment liquid is, for example, a liquid containing 1H,1H,7H-Dodecafluoroheptanol (rational formula: H(CF2)6CH2OH) as a fluorine-containing alcohol (hereinafter also referred to as the "first drying treatment liquid"). The drying treatment liquid may also be a liquid containing 1H,1H,3H-Tetrafluoropropanol (rational formula: CHF2CF2CH2OH) as a fluorine-containing alcohol (hereinafter also referred to as the "second drying treatment liquid"). Alternatively, the drying treatment liquid may be a liquid containing 2-(Perfluorohexyl)ethanol (rational formula: F(CF2)6CH2CH2OH) as a fluorine-containing alcohol (hereinafter also referred to as the "third drying treatment liquid"). The first drying treatment liquid and the second drying treatment liquid each contain a fluorine-containing alcohol having -CF2H at the terminal. The third drying treatment liquid contains a fluorine-containing alcohol having -CF3 at the terminal.

[0050] The drying treatment liquid may be a liquid other than the first drying treatment liquid, the second drying treatment liquid, and the third drying treatment liquid. The drying treatment liquid may be a single liquid or a mixed liquid containing two or more liquids. Preferably, the drying treatment liquid contains at least one liquid selected from the group consisting of the first drying treatment liquid, the second drying treatment liquid, and the third drying treatment liquid.

[0051] In this embodiment, the first drying treatment liquid consists essentially of 1H,1H,7H-Dodecafluoroheptanol only. The second drying treatment liquid consists essentially of 1H,1H,3H-Tetrafluoropropanol only. The third drying treatment liquid consists essentially of 2-(Perfluorohexyl)ethanol only. The molecular weight of the first drying treatment liquid is 332.1 (g / mol) and the specific gravity (d20) is 1.76 (g / cm 3 ) and the boiling point is 169°C to 170°C. The molecular weight of the second drying treatment liquid is 132.1 (g / mol), and the specific gravity (d20) is 1.49 (g / cm 3 ) and the boiling point is 109°C to 110°C. The molecular weight of the third drying treatment liquid is 364.1 (g / mol), and the specific gravity (d20) is 1.68 (g / cm 3 ) and has a boiling point of 190° C. to 200° C. The first drying treatment liquid, the second drying treatment liquid, and the third drying treatment liquid are all available from Daikin Industries, Ltd.

[0052] In the substrate processing apparatus 1, when a chemical liquid is supplied from the first nozzle 51 to the substrate 9, the first nozzle 51 is located at the supply position, and the second nozzle 52, the third nozzle 53, and the fourth nozzle 54 are located at the retracted positions. When a rinse liquid is supplied from the second nozzle 52 to the substrate 9, the second nozzle 52 is located at the supply position, and the first nozzle 51, the third nozzle 53, and the fourth nozzle 54 are located at the retracted positions. When a replacement liquid is supplied from the third nozzle 53 to the substrate 9, the third nozzle 53 is located at the supply position, and the first nozzle 51, the second nozzle 52, and the fourth nozzle 54 are located at the retracted positions. When a drying processing liquid is supplied from the fourth nozzle 54 to the substrate 9, the fourth nozzle 54 is located at the supply position, and the first nozzle 51, the second nozzle 52, and the third nozzle 53 are located at the retracted positions.

[0053] The upper nozzle 55 is connected to a gas supply source 552 via a pipe 553 and a valve 554. When the valve 554 is opened under the control of the control unit 8, an inert gas such as nitrogen (N2) gas is supplied from the tip of the upper nozzle 55 to the space between the upper surface 91 of the substrate 9 and the lower surface of the top plate 61 (see FIG. 2). The inert gas may be a gas other than nitrogen (for example, argon (Ar) gas).

[0054] The lower nozzle 56 is connected to a fluid supply source 562 via a pipe 563 and a valve 564. When the valve 564 is opened under the control of the control unit 8, a fluid is ejected from the tip of the lower nozzle 56 toward the center of the lower surface 92 of the substrate 9. The fluid supplied from the lower nozzle 56 may be, for example, a liquid or a gas. The fluid may also be a fluid heated to a temperature higher than room temperature (for example, 25°C).

[0055] Next, a processing flow of a substrate 9 in the substrate processing apparatus 1 of FIG. 2 will be described with reference to FIG. 5. In the substrate processing apparatus 1, first, a substrate 9 having a fine pattern preliminarily formed on its upper surface 91 is held horizontally by the substrate holder 31. Next, supply of an inert gas (e.g., nitrogen gas) from the upper nozzle 55 begins. The flow rate of the inert gas supplied from the upper nozzle 55 is, for example, 10 liters / min. Then, rotation of the substrate 9 is started by the substrate rotation mechanism 33. The rotation speed of the substrate 9 is, for example, 800 rpm to 1000 rpm. Then, rotation of the top plate 61 is started by the top plate rotation mechanism 62. The rotation direction and rotation speed of the top plate 61 are, for example, the same as the rotation direction and rotation speed of the substrate 9. The top plate 61 is positioned in the vertical direction at a position where the first nozzle 51 and the like can be arranged between the top plate 61 and the substrate 9 (hereinafter also referred to as the "first processing position").

[0056] Then, with the first nozzle 51 positioned at the supply position, a chemical liquid (e.g., hydrofluoric acid) is supplied from the first nozzle 51 to the center of the upper surface 91 of the substrate 9 (step S11). The chemical liquid supplied to the center of the substrate 9 spreads radially outward from the center of the substrate 9 due to centrifugal force caused by the rotation of the substrate 9, and is applied to the entire upper surface 91 of the substrate 9. The chemical liquid scatters or flows out radially outward from the outer edge of the substrate 9. The chemical liquid that scatters or flows out from the substrate 9 is received and recovered by a cup portion or the like (not shown). The same applies to other processing liquids. In the substrate processing apparatus 1, the chemical liquid is applied to the substrate 9 for a predetermined period of time, thereby performing chemical processing on the substrate 9.

[0057] When the chemical liquid processing of the substrate 9 is completed, the first nozzle 51, which has stopped discharging the chemical liquid, is moved from the supply position to the retracted position, and the second nozzle 52 is moved from the retracted position to the supply position. Then, a rinse liquid (e.g., DIW) is supplied from the second nozzle 52 to the center of the upper surface 91 of the substrate 9 (step S12). The rotation speed of the substrate 9 during the supply of the rinse liquid is, for example, 800 rpm to 1200 rpm. The rinse liquid supplied to the center of the substrate 9 spreads radially outward from the center of the substrate 9 due to centrifugal force caused by the rotation of the substrate 9, and is applied to the entire upper surface 91 of the substrate 9. The chemical liquid on the substrate 9 is moved radially outward by the rinse liquid and removed from the substrate 9. In the substrate processing apparatus 1, the rinse liquid is applied to the substrate 9 for a predetermined period of time, thereby performing the rinse processing of the substrate 9.

[0058] Once the chemical liquid has been removed from substrate 9 (i.e., once all of the chemical liquid on substrate 9 has been replaced with rinse liquid), the rotation speed of substrate 9 is reduced. As a result, a liquid film of rinse liquid is formed and maintained on upper surface 91 of substrate 9. The rotation speed of substrate 9 is, for example, 10 rpm. The liquid film of rinse liquid covers the entire upper surface 91 of substrate 9. Once the liquid film of rinse liquid has been formed, the discharge of rinse liquid from second nozzle 52 is stopped, and second nozzle 52 is retracted from the supply position to the retracted position. The rotation speed of substrate 9 may be any speed at which upper surface 91 of substrate 9 does not dry out, and may be, for example, 10 rpm or higher.

[0059] Next, the third nozzle 53 is moved from the retracted position to the supply position, and the substitute liquid is supplied from the third nozzle 53 to the center of the upper surface 91 of the substrate 9 (i.e., the center of the liquid film of the rinse liquid) (step S13). The substitute liquid is, for example, IPA. The rotation speed of the substrate 9 during the supply of the substitute liquid is, for example, 100 rpm to 300 rpm. The substitute liquid supplied to the center of the substrate 9 spreads radially outward from the center of the substrate 9 due to centrifugal force caused by the rotation of the substrate 9, and is applied to the entire upper surface 91 of the substrate 9. The rinse liquid on the substrate 9 (i.e., the rinse liquid in contact with the upper surface 91 of the substrate 9) is moved radially outward by the substitute liquid and removed from the substrate 9. In the substrate processing apparatus 1, the substitute liquid is applied to the substrate 9 for a predetermined time, thereby performing a process of replacing the rinse liquid with the substitute liquid on the substrate 9.

[0060] Once the rinse liquid has been removed from the substrate 9 (i.e., once all of the rinse liquid on the substrate 9 has been replaced with the replacement liquid), the rotation speed of the substrate 9 is reduced. As a result, a liquid film of the replacement liquid is formed and maintained on the upper surface 91 of the substrate 9. The rotation speed of the substrate 9 is, for example, 10 rpm. The liquid film of the replacement liquid covers the entire upper surface 91 of the substrate 9. Once the liquid film of the replacement liquid has been formed, the discharge of the replacement liquid from the third nozzle 53 is stopped, and the third nozzle 53 is retracted from the supply position to the retracted position. The rotation speed of the substrate 9 may be any speed at which the upper surface 91 of the substrate 9 does not dry out, and may be, for example, 10 rpm or higher.

[0061] Next, the fourth nozzle 54 is moved from the retracted position to the supply position, and the drying treatment liquid is supplied from the fourth nozzle 54 to the center of the upper surface 91 of the substrate 9 (i.e., the center of the liquid film of the replacement liquid) (step S14). The drying treatment liquid is, for example, the first drying treatment liquid or the second drying treatment liquid described above. The rotation speed of the substrate 9 during the supply of the drying treatment liquid is, for example, 100 rpm to 300 rpm. The drying treatment liquid supplied to the center of the substrate 9 spreads radially outward from the center of the substrate 9 due to centrifugal force caused by the rotation of the substrate 9, and is applied to the entire upper surface 91 of the substrate 9. The replacement liquid on the substrate 9 (i.e., the replacement liquid in contact with the upper surface 91 of the substrate 9) is moved radially outward by the drying treatment liquid and removed from the substrate 9. In the substrate processing apparatus 1, the replacement liquid on the substrate 9 is entirely replaced with the drying treatment liquid by applying the drying treatment liquid to the substrate 9 for a predetermined time.

[0062] The drying treatment liquid is preheated by the liquid heating unit 545 (see FIG. 4 ) before being discharged from the fourth nozzle 54 so that the temperature of the drying treatment liquid when it contacts the upper surface 91 of the substrate 9 in step S14 will be a predetermined contact temperature. Considering the temperature drop of the drying treatment liquid due to contact with the substrate 9, the temperature of the drying treatment liquid discharged from the fourth nozzle 54 is preferably set to, for example, a temperature slightly higher than the contact temperature (but lower than the boiling point of the drying treatment liquid). Furthermore, in cases where the temperature of the drying treatment liquid does not drop significantly due to contact with the substrate 9, the temperature of the drying treatment liquid discharged from the fourth nozzle 54 may be, for example, approximately the same as the contact temperature. In other words, the drying treatment liquid preheated to the contact temperature may be supplied to the upper surface 91 of the substrate 9.

[0063] The contact temperature is a temperature equal to or higher than the boiling point of the rinsing liquid and lower than the boiling point of the drying treatment liquid. This suppresses evaporation of the drying treatment liquid on the substrate 9, and even if a component of the rinsing liquid (e.g., moisture) is mixed into the drying treatment liquid, the component of the rinsing liquid is evaporated and removed from the drying treatment liquid. Furthermore, when water is used as the rinsing liquid, the drying treatment liquid is set to a temperature equal to or higher than the boiling point of the rinsing liquid, thereby preventing moisture in the air from condensing and being mixed into the drying treatment liquid. Preferably, the difference between the contact temperature and the boiling point of the drying treatment liquid is 65°C or lower. In other words, the contact temperature is preferably lower than the boiling point of the drying treatment liquid and higher than a temperature that is 65°C lower than the boiling point of the drying treatment liquid.

[0064] Even after the replacement liquid is removed from the substrate 9, the heated drying treatment liquid is continuously supplied from the fourth nozzle 54 to the upper surface 91 of the substrate 9. This maintains the temperature of the drying treatment liquid in contact with the upper surface 91 of the substrate 9 at the contact temperature. In step S14, the drying treatment liquid at the contact temperature comes into contact with the entire upper surface 91 of the substrate 9 for a predetermined contact time (preferably, 10 seconds or more). This causes molecules of the drying treatment liquid to be adsorbed onto the upper surface 91 of the substrate 9 and the surface of the pattern on the upper surface 91 of the substrate 9.

[0065] FIG. 6A is a diagram schematically showing molecules of a first drying treatment liquid (i.e., 1H,1H,7H-Dodecafluoroheptanol) adsorbed onto the upper surface 91 of the substrate 9. FIG. 6B is a diagram schematically showing molecules of a second drying treatment liquid (i.e., 1H,1H,3H-Tetrafluoropropanol) adsorbed onto the upper surface 91 of the substrate 9. FIG. 6C is a diagram schematically showing molecules of a third drying treatment liquid (i.e., 2-(Perfluorohexyl)ethanol) adsorbed onto the upper surface 91 of the substrate 9. In FIGS. 6A to 6C, the molecules of the first drying treatment liquid, the second drying treatment liquid, and the third drying treatment liquid are shown by their skeletal structural formulas.

[0066] As shown in FIG. 6A, hydroxy groups (—OH) of the first drying treatment liquid attract oxygen atoms (O) on the upper surface 91 of the substrate 9, causing molecules of the first drying treatment liquid to adsorb onto the upper surface 91 of the substrate 9. As a result, the upper surface 91 of the substrate 9 is covered with molecules of the first drying treatment liquid. Specifically, the upper surface 91 of the substrate 9 is covered with —CF2H present at the ends of the molecules of the first drying treatment liquid. Similarly, in the case of the second drying treatment liquid shown in FIG. 6B, molecules of the second drying treatment liquid adsorb onto the upper surface 91 of the substrate 9, causing the upper surface 91 of the substrate 9 to be covered with —CF2H present at the ends of the molecules of the second drying treatment liquid. In substantially the same manner, in the case of the third drying treatment liquid shown in FIG. 6C, molecules of the third drying treatment liquid adsorb onto the upper surface 91 of the substrate 9, causing the upper surface 91 of the substrate 9 to be covered with —CF3 present at the ends of the molecules of the third drying treatment liquid. 6A to 6C are schematic diagrams, and therefore the adsorption directions and adsorption densities of the first drying treatment liquid, the second drying treatment liquid, and the third drying treatment liquid to the substrate 9 differ from the actual ones.

[0067] Similarly, for the pattern on the upper surface 91 of the substrate 9, molecules of the first drying treatment liquid are adsorbed onto the pattern surface, and the pattern surface is covered with -CF2H present at the ends of the molecules of the first drying treatment liquid. As a result, the surface free energy of the pattern is reduced compared to when the first drying treatment liquid is not adsorbed onto the pattern surface, and the contact angle of the first drying treatment liquid with respect to the pattern surface increases and approaches 90°. Similarly, for the second drying treatment liquid, molecules of the second drying treatment liquid are adsorbed onto the pattern surface, and the pattern surface is covered with -CF2H present at the ends of the molecules of the second drying treatment liquid. As a result, the surface free energy of the pattern is reduced compared to when the second drying treatment liquid is not adsorbed onto the pattern surface, and the contact angle of the second drying treatment liquid with respect to the pattern surface increases and approaches 90°. In substantially the same manner, for the third drying treatment liquid, molecules of the third drying treatment liquid are adsorbed onto the pattern surface, and the pattern surface is covered with -CF3 present at the ends of the molecules of the third drying treatment liquid. As a result, the surface free energy of the pattern decreases compared to when the third drying treatment liquid is not adsorbed on the pattern surface, and the contact angle of the third drying treatment liquid with respect to the pattern surface increases and approaches 90°. Regardless of whether the first, second, or third drying treatment liquid is adsorbed on the pattern surface, the surface free energy of the pattern to which the drying treatment liquid is adsorbed becomes lower than the surface free energy of silicon (Si) to which no drying treatment liquid is adsorbed.

[0068] On the pattern surface, the longer the fluorinated alkyl chain of the fluorine-containing alcohol molecule, the closer to perpendicular the adsorption direction of the drying treatment liquid molecules to the pattern surface, resulting in a higher molecular orientation of the drying treatment liquid on the pattern surface. The number of C atoms contained in the molecules of the first drying treatment liquid shown in FIG. 6A is 7, and the number of C atoms contained in the molecules of the second drying treatment liquid shown in FIG. 6B is 3. Thus, since the molecules of the first drying treatment liquid have longer fluorinated alkyl chains than the molecules of the second drying treatment liquid, the adsorption direction of the molecules of the first drying treatment liquid is closer to perpendicular than the adsorption direction of the molecules of the second drying treatment liquid. Therefore, the molecules of the first drying treatment liquid are adsorbed to the pattern surface at a higher density than the molecules of the second drying treatment liquid. As a result, when the first drying treatment liquid is used as the drying treatment liquid, the decrease in the surface free energy of the pattern is greater than when the second drying treatment liquid is used, and the contact angle with respect to the pattern surface is closer to 90°.

[0069] After the drying processing liquid at the contact temperature has been brought into contact with the entire upper surface 91 of the substrate 9, and the aforementioned contact time has elapsed, the discharge of the drying processing liquid from the fourth nozzle 54 stops, and the fourth nozzle 54 retreats from the supply position to the retreat position. Then, the top plate 61 descends from the first processing position to a position (hereinafter also referred to as the "second processing position") closer to the upper surface 91 of the substrate 9. This substantially blocks the space between the upper surface 91 of the substrate 9 and the lower surface of the top plate 61 from the surrounding space (i.e., the space radially outside the substrate 9).

[0070] Then, the rotation speed of the substrate 9 by the substrate rotation mechanism 33 is increased, and the substrate 9 is rotated at high speed, so that the drying treatment liquid present on the upper surface 91 of the substrate 9 is moved radially outward by centrifugal force and removed from the substrate 9. In the substrate processing apparatus 1, the high-speed rotation of the substrate 9 by the substrate rotation mechanism 33 is continued for a predetermined time, thereby performing a drying treatment (so-called spin-drying treatment) of the substrate 9 (step S15). The substrate rotation mechanism 33 is a drying treatment section that dries the substrate 9 by removing the liquid drying treatment liquid from the upper surface 91 of the substrate 9.

[0071] During the drying process of the substrate 9, when the liquid level of the drying process liquid has descended to a position between the patterns, a capillary force acts to pull the patterns in the horizontal direction. The capillary force σmax is expressed by the following formula (1) using the surface tension γ of the drying process liquid, the contact angle θ between the drying process liquid and the patterns, the distance D between the patterns, the height H of the patterns, and the width W of the patterns.

[0072] σmax=(6γ cosθ / D) (H / W) 2 · · Equation (1)

[0073] As described above, in the substrate processing apparatus 1, the surface tension γ of the drying processing liquid is lower than the surface tension of the rinse liquid. Therefore, in the drying processing of step S15, the capillary force σmax acting on the pattern can be made smaller than when the rinse liquid (e.g., DIW) remaining on the substrate 9 after the rinse processing is removed by a spin-drying process or the like to dry the substrate 9 (hereinafter also referred to as a "rinse-drying process"). As a result, in the drying processing of step S15, collapse of the pattern can be suppressed more effectively than in the rinse-drying process.

[0074] Furthermore, in the substrate processing apparatus 1, the surface free energy of the pattern is reduced by adsorbing the fluorine-containing alcohol contained in the drying processing liquid onto the surface of the pattern. Therefore, compared to the case where the rinsing liquid remaining on the substrate 9 after the rinsing processing is replaced with a replacement liquid (e.g., IPA) and the replacement liquid is removed by a spin-drying process or the like to dry the substrate 9 (hereinafter also referred to as a "replacement drying process"), the contact angle θ on the surface of the pattern can be increased and brought closer to 90°. Therefore, in the drying process of step S15, the capillary force σ acting on the pattern can be reduced compared to the replacement drying process. As a result, in the drying process of step S15, collapse of the pattern can be suppressed more effectively than in the replacement drying process.

[0075] Conventional replacement drying processes use IPA, methanol, ethanol, or other replacement liquids. Although IPA, methanol, and ethanol can adsorb to the pattern surface through -OH, they do not contain fluorine and therefore do not contribute much to reducing the surface free energy of the pattern. Therefore, there is a limit to how effectively they can prevent pattern collapse during drying.

[0076] Furthermore, if HFE (hydrofluoroether), HFC (hydrofluorocarbon), or HFO (hydrofluoroolefin) were used instead of the drying treatment liquid in step S14, the molecules of these liquids would not substantially adsorb to the pattern surface because they do not have functional groups at their ends that are easily adsorbed to the pattern surface, such as -OH. Therefore, the surface free energy of the pattern would not substantially decrease. Therefore, it would not be possible to effectively prevent the pattern from collapsing during the drying treatment.

[0077] 7 and 8 show experimental comparisons of the collapse rate of the pattern on the substrate 9 after the processing of steps S11 to S15 and the collapse rate of the pattern on the substrate 9 after the above-mentioned replacement drying process (i.e., after steps S11 to S13, step S14 is omitted, and the replacement liquid on the substrate 9 is removed by spin drying and then dried). In FIGS. 7 and 8, experiments were conducted using test coupons on whose surfaces patterns were formed. FIG. 7 shows the results of an experiment using a test coupon having a hydrophilic surface on which a SiO2 film was formed by natural oxidation. FIG. 8 shows the results of an experiment using a test coupon having a hydrophobic surface in which the SiO2 film was etched.

[0078] The vertical axes in Figures 7 and 8 represent the collapse rate of the pattern on the surface of the test coupon. "Examples 1 and 6" on the horizontal axes in Figures 7 and 8 represent experimental results corresponding to the process of steps S11 to S15 described above using the first drying process liquid as the drying process liquid. "Example 2" on the horizontal axes represent experimental results corresponding to the process of steps S11 to S15 described above using the second drying process liquid as the drying process liquid. "Examples 3 to 5 and 7" on the horizontal axes represent experimental results corresponding to the process of steps S11 to S15 described above using the third drying process liquid as the drying process liquid. Furthermore, "Comparative Example 1" on the horizontal axes represents experimental results corresponding to the substitution drying process using IPA as the substitution liquid (i.e., the process in which step S14 was omitted). "Comparative Example 2" on the horizontal axis shows the experimental results corresponding to the processing of steps S11 to S15 described above, in which HFE-7100 (rational formula: C4F9OCH3, methoxy-nonafluorobutane), a type of HFE, was used instead of the drying processing liquid in the processing of step S14.

[0079] The test coupon is a roughly rectangular, flat member measuring 20 mm square. The AR (Aspect Ratio: ratio of the bottom to the height of the pattern) of the pattern formed on the surface of the test coupon is 20.

[0080] In Example 1 in Figure 7, a test coupon was immersed in the first drying treatment liquid in a beaker at the contact temperature for 1 minute, and then removed from the beaker and allowed to dry naturally. The contact temperature was 10°C lower than the boiling point of the first drying treatment liquid. The pattern collapse rate on the test coupon was then determined. For substrate 9 having a hydrophilic surface, the pattern collapse rate in Example 1 was approximately 47%. The pattern collapse rate was determined by performing image analysis of the test coupon. The pattern collapse rate was determined in the same manner in Examples 2 to 7 and Comparative Examples 1 and 2.

[0081] In relation to Example 1, the contact temperature of the first drying treatment liquid was varied within a range below the boiling point of the first drying treatment liquid to determine the pattern collapse rate, and the result was that the collapse rate increased as the difference between the contact temperature and the boiling point increased. Furthermore, in relation to Example 1, the contact time was varied and the contact angle of the first drying treatment liquid with the test coupon was measured. As a result, the contact angle increased as the contact time increased within a range of 15 minutes or less, but the contact angle did not change much once the contact time was 15 minutes or more.

[0082] 7 is the same as Example 1, except that the first drying treatment liquid was changed to a second drying treatment liquid and the contact temperature was set to a temperature 10°C lower than the boiling point of the second drying treatment liquid. For substrate 9 having a hydrophilic surface, the pattern collapse rate in Example 2 was approximately 53%.

[0083] 7 is the same as Example 1, except that the first drying treatment liquid was changed to a third drying treatment liquid and the contact temperature was set to a temperature 40° C. lower than the boiling point of the third drying treatment liquid. For substrate 9 having a hydrophilic surface, the pattern collapse rate in Example 3 was approximately 13%.

[0084] 7 is the same as Example 1, except that the first drying treatment liquid was changed to the third drying treatment liquid and the contact temperature was set to a temperature 65° C. lower than the boiling point of the third drying treatment liquid. For substrate 9 having a hydrophilic surface, the pattern collapse rate in Example 4 was approximately 17%.

[0085] 7 is the same as Example 1, except that the first drying treatment liquid was changed to the third drying treatment liquid and the contact temperature was set to a temperature 90° C. lower than the boiling point of the third drying treatment liquid. For substrate 9 having a hydrophilic surface, the pattern collapse rate in Example 5 was approximately 31%.

[0086] 7 is the same as Example 1, except that the first drying treatment liquid was changed to IPA and the contact temperature was set to a temperature 10°C lower than the boiling point of IPA. For substrate 9 having a hydrophilic surface, the pattern collapse rate in Comparative Example 1 was approximately 86%.

[0087] 7, by performing the above-described steps S11 to S15 (Examples 1 to 5) on a substrate 9 having a hydrophilic surface, pattern collapse could be suppressed compared to a displacement drying process in which step S14 was omitted (Comparative Example 1). That is, even for a substrate 9 having a hydrophilic surface in which the rate of pattern collapse is higher than that of a hydrophobic surface in the conventional drying process (Comparative Example 1), pattern collapse can be suppressed by performing the steps S11 to S15 (Examples 1 to 5) according to the present invention.

[0088] Comparing Example 1 with Example 2, the use of the first drying treatment liquid (Example 1) having seven carbon atoms in its molecular formula among the first and second drying treatment liquids having -CF2H at their terminals further suppressed pattern collapse compared to the use of the second drying treatment liquid (Example 2) having three carbon atoms in its molecular formula. Comparing Example 1 with Examples 3 to 5, the use of the third drying treatment liquid (Examples 3 to 5) having -CF3 at its terminals further suppressed pattern collapse compared to the use of the first drying treatment liquid (Example 1) having -CF2H at its terminals. Comparing Examples 3 to 4 with Example 5, the use of a difference between the contact temperature and the boiling point of the third drying treatment liquid of 65°C or less (Examples 3 and 4) further suppressed pattern collapse compared to the use of a difference between the contact temperature and the boiling point of the third drying treatment liquid of more than 65°C (Example 5: temperature difference of 90°C).

[0089] In Example 6 shown in FIG. 8, a test coupon was immersed in a beaker for 1 minute in dilute hydrofluoric acid (concentration: approximately 1% by volume), then in DIW for 1 minute, and then in IPA for 3 minutes, and then in a first drying treatment liquid at room temperature. The first drying treatment liquid was then heated to a contact temperature 10°C lower than the boiling point of the first drying treatment liquid and maintained at this temperature for 1 minute. The test coupon was then removed from the beaker and allowed to air dry, and the pattern collapse rate was determined. For substrate 9 having a hydrophobic surface, the pattern collapse rate for Example 6 was approximately 10%.

[0090] 8 is the same as Example 6, except that the first drying treatment liquid was changed to the third drying treatment liquid and the contact temperature was set to a temperature 40° C. lower than the boiling point of the third drying treatment liquid. For substrate 9 having a hydrophilic surface, the pattern collapse rate in Example 7 was approximately 17%.

[0091] 8 is the same as Example 6, except that the first drying treatment liquid was changed to HFE-7100 and the contact temperature was set to a temperature 10°C lower than the boiling point of HFE-7100. For substrate 9 having a hydrophobic surface, the pattern collapse rate in Comparative Example 2 was approximately 62%.

[0092] 8, by performing the above-described steps S11 to S15 on a substrate 9 having a hydrophobic surface using a drying treatment liquid (Examples 6 and 7), pattern collapse could be suppressed compared to when steps S11 to S15 were performed using HFE (Comparative Example 2). Furthermore, comparing Example 6 and Example 7, the use of the first drying treatment liquid having -CF2H at its terminal (Example 6) further suppressed pattern collapse compared to when the third drying treatment liquid having -CF3 at its terminal (Example 7) was used.

[0093] After the above-mentioned step S15 (drying process of the substrate 9) is completed, the substrate 9 is heated by the substrate heating unit 7, thereby removing molecules of the drying process liquid adsorbed to the surface of the substrate 9 (i.e., the surface of the pattern on the substrate 9, etc.) (step S16). In the adsorbed molecule removal process of step S16, the temperature of the substrate 9 (hereinafter also referred to as the "molecule removal temperature") is set to a temperature higher than the boiling point of the above-mentioned drying process liquid. The molecules of the drying process liquid removed from the substrate 9 in step S16 are not the liquid drying process liquid, but a small number of molecules that remain adsorbed on the substrate 9 even after the liquid drying process liquid has been removed from the substrate 9 in the drying process of step S15. After the step S16 is completed, the substrate 9 is unloaded from the substrate processing apparatus 1.

[0094] In the above example, the adsorbed molecule removal process in step S16 is performed on the substrate 9 held by the substrate holder 31 in the same chamber 11 in which steps S11 to S15 are performed, but this is not limiting. For example, a hot plate may be provided separately from the substrate holder 31 in the same chamber 11, and the substrate 9 after step S15 may be placed on the hot plate and heated to perform the adsorbed molecule removal process. Alternatively, the substrate 9 after step S15 may be transferred from the processing unit 108 of the substrate processing apparatus 1 to another processing unit 108 (see FIG. 1), and the substrate 9 may be subjected to the adsorbed molecule removal process in the other processing unit 108 by ashing using plasma, UV, excimer, or the like.

[0095] In the above example, the replacement of the rinse liquid with the replacement liquid in step S13 is performed between the rinse process in step S12 and the supply of the drying process liquid in step S14. However, if the rinse liquid can be suitably removed from the substrate 9 by directly supplying the drying process liquid to the liquid film of the rinse liquid on the substrate 9, step S13 may be omitted. For example, if the affinity between the rinse liquid and the drying process liquid is relatively high, step S13 can be omitted. Also, for example, if the specific gravity of the drying process liquid is somewhat higher than that of the rinse liquid and the drying process liquid is supplied at a small flow rate to the liquid film of the rinse liquid so that the drying process liquid settles to the bottom of the liquid film.

[0096] In the above example, in step S14, a preheated drying treatment liquid is supplied onto the substrate 9, so that the drying treatment liquid at the contact temperature comes into contact with the substrate 9; however, this is not limiting. For example, a preheated drying treatment liquid may be supplied onto the substrate 9, and the drying treatment liquid on the substrate 9 may be heated by the substrate heating unit 7, so that the temperature of the drying treatment liquid is raised to the contact temperature and maintained at the contact temperature. The drying treatment liquid on the substrate 9 may be heated by a configuration other than the substrate heating unit 7. For example, the drying treatment liquid on the substrate 9 may be heated by supplying heated inert gas from the lower nozzle 56 to the lower surface 92 of the substrate 9.

[0097] Next, a substrate processing system 10a according to a second embodiment of the present invention will be described. Fig. 9 is a schematic plan view showing the layout of the substrate processing system 10a. The substrate processing system 10a is a batch-type apparatus that performs liquid processing on a plurality of substrates 9 at once.

[0098] The substrate processing system 10a includes a carrier holder 104a, a substrate transfer robot 111a, a posture conversion mechanism 112a, a pusher 113a, a substrate transport mechanism 114a, a substrate processing apparatus 1a serving as a processing unit, and a controller 8a. The controller 8a has a structure substantially similar to that of the controller 8 described above, and controls the substrate transfer robot 111a, posture conversion mechanism 112a, pusher 113a, substrate transport mechanism 114a, and substrate processing apparatus 1a. The substrate transfer robot 111a, posture conversion mechanism 112a, pusher 113a, substrate transport mechanism 114a, and substrate processing apparatus 1a are housed inside a chamber 11a.

[0099] The carrier holding unit 104a holds a carrier 107a (e.g., a FOUP). The substrate transfer robot 111a takes out a plurality of (e.g., 25) substrates 9 in a horizontal position from the carrier 107a held by the carrier holding unit 104a and transfers them to the position conversion mechanism 112a. The plurality of substrates 9 are arranged at approximately equal intervals in the thickness direction. The position conversion mechanism 112a converts the orientation of the plurality of substrates 9 between a horizontal position and an upright position (i.e., a position in which the main surfaces of the substrates 9 are approximately parallel to the up-down direction). The position conversion mechanism 112a includes, for example, a holding unit that holds the plurality of substrates 9 and a rotation mechanism that rotates the holding unit by 90°. The rotation mechanism may have various structures, for example, an electric rotary motor.

[0100] The attitude conversion mechanism 112a converts the plurality of substrates 9 received from the substrate transfer robot 111a from a horizontal attitude to an upright attitude. The pusher 113a receives the plurality of substrates 9 in an upright attitude from the attitude conversion mechanism 112a and passes them to the substrate transport mechanism 114a. The substrate transport mechanism 114a includes a holder that holds the plurality of substrates 9 in an upright attitude and a movement mechanism that moves the holder in a horizontal direction. The movement mechanism includes, for example, an electric linear motor, an air cylinder, or a ball screw and an electric rotary motor. The substrate transport mechanism 114a loads the plurality of substrates 9 in an upright attitude into the substrate processing apparatus 1a, which is a processing unit. The processing of the substrates 9 in the substrate processing apparatus 1a will be described later.

[0101] The substrates 9 processed in the substrate processing apparatus 1a are removed from the substrate processing apparatus 1a by the substrate transport mechanism 114a and transferred to the attitude conversion mechanism 112a by the pusher 113a. The attitude conversion mechanism 112a converts the upright substrates 9 into a horizontal attitude and transfers them to the substrate transfer robot 111a. The substrate transfer robot 111a transfers the horizontally oriented substrates 9 into the carrier 107a.

[0102] The substrate processing apparatus 1a includes a first processing unit 21, a second processing unit 22, a third processing unit 23, a fourth processing unit 24, a fifth processing unit 25, a lifter 26, and a lifter 27. The first processing unit 21 includes a processing tank 211 in which the above-mentioned chemical liquid is stored. The second processing unit 22 includes a processing tank 221 in which the above-mentioned rinse liquid is stored. The third processing unit 23 includes a processing tank 231 in which the above-mentioned substitute liquid is stored. The fourth processing unit 24 includes a processing tank 241 in which the above-mentioned drying processing liquid is stored. As in the case of the substrate processing apparatus 1, the drying processing liquid includes a fluorine-containing alcohol. The drying processing liquid includes, for example, a fluorine-containing alcohol having -CF2H or -CF3 at its terminal end. The surface tension of the drying processing liquid is lower than that of the rinse liquid, and the boiling point of the drying processing liquid is higher than that of the rinse liquid.

[0103] Lifters 26 and 27 are substrate holders that receive and hold a plurality of substrates 9 in an upright position from substrate transport mechanism 114a. Lifter 26 moves between first processing section 21 and second processing section 22 while holding a plurality of substrates 9 in an upright position. Lifter 27 moves between third processing section 23 and fourth processing section 24 while holding a plurality of substrates 9 in an upright position. Furthermore, lifters 26 and 27 each move the plurality of substrates 9 that they hold in the vertical direction. The movement of lifters 26 and 27 and the raising and lowering of the plurality of substrates 9 are achieved by, for example, an electric linear motor, an air cylinder, or a ball screw and an electric rotary motor.

[0104] 10 is a side view showing first processing unit 21 and lifter 26. In FIG. 10, processing tank 211 is shown in cross section, along with substrate 9 held by lifter 26. First processing unit 21 includes processing tank 211 having a substantially pentagonal cross section, and processing liquid supply pipe 212 and gas supply pipe 213 provided at the bottom of processing tank 211. Second processing unit 22, third processing unit 23, and fourth processing unit 24 have substantially the same structure as first processing unit 21.

[0105] The lifter 26 includes a substantially flat plate-shaped main body 261 extending substantially parallel to the vertical direction, and three holding rods 262 extending horizontally from one main surface of the main body 261. In the lifter 26, the lower edges of a plurality of substrates 9 arranged in an upright position in a direction perpendicular to the plane of the drawing are held by the three holding rods 262. The lifter 26 further includes an elevating mechanism 263 that moves the main body 261 in the vertical direction. The elevating mechanism 263 includes, for example, an electric linear motor, an air cylinder, or a ball screw and an electric rotary motor connected to the main body 261.

[0106] In first processing apparatus 21, the chemical solution supplied from processing solution supply pipe 212 is stored in processing tank 211. Then, with the supply of the chemical solution from processing solution supply pipe 212 continuing, a plurality of substrates 9 held by lifter 26 are immersed in the chemical solution in processing tank 211. Next, an inert gas such as nitrogen gas is supplied from gas supply pipe 213, and bubbles of the inert gas rise up in processing tank 211. This agitates the chemical solution near the surfaces of substrates 9, and fresh chemical solution is continuously supplied to the surfaces of substrates 9. As a result, the speed of chemical solution processing of substrates 9 is increased.

[0107] The fifth processing unit 25 shown in FIG. 9 includes a substrate holder 252 that holds multiple substrates 9 in an upright position, and performs a process of removing liquid from the surfaces of the multiple substrates 9 held by the substrate holder 252 (i.e., a drying process). In the fifth processing unit 25, the drying process may be performed by, for example, spinning off liquid from the surfaces of the multiple substrates 9 using centrifugal force. Alternatively, the drying process may be performed by supplying an organic solvent (e.g., IPA) to the multiple substrates 9. The drying process in the fifth processing unit 25 may be performed by various other methods. The fifth processing unit 25 also includes a substrate heating unit 253 that heats the multiple substrates 9 held by the substrate holder 252. The substrate heating unit 253 heats the substrates 9 by, for example, irradiating them with light. Note that the substrate heating unit 253 may heat the substrates 9 by a method other than light irradiation.

[0108] Next, the flow of processing substrates 9 in substrate processing apparatus 1a will be described. In substrate processing apparatus 1a, first, lifter 26 receives and holds multiple substrates 9 in an upright position from substrate transport mechanism 114a. Next, lifter 26 lowers multiple substrates 9 and immerses them in the chemical solution stored in processing tank 211 of first processing apparatus 21. This causes the chemical solution to be supplied to the entire surface (i.e., both main surfaces and side surfaces) of each substrate 9 (FIG. 5: step S11). In substrate processing apparatus 1a, multiple substrates 9 are immersed in the chemical solution for a predetermined time in first processing apparatus 21, which is a chemical solution supply unit, whereby chemical processing of substrates 9 is performed.

[0109] When the chemical processing of the substrates 9 is completed, the lifter 26 lifts the plurality of substrates 9 from the processing tank 211 of the first processing unit 21 and transports them to the second processing unit 22. The lifter 26 then lowers the plurality of substrates 9 and immerses them in the rinse liquid stored in the processing tank 221 of the second processing unit 22. This causes the rinse liquid to be supplied to the entire surface of each substrate 9 (step S12). In the substrate processing apparatus 1a, the plurality of substrates 9 are immersed in the rinse liquid for a predetermined time in the second processing unit 22, which is a rinse liquid supply unit, thereby performing a rinse processing of the substrates 9.

[0110] When the rinsing process of the substrates 9 is completed, the lifter 26 lifts up the plurality of substrates 9 from the processing bath 221 of the second processing unit 22 and transfers them to the substrate transport mechanism 114a. The substrate transport mechanism 114a transfers the plurality of substrates 9 to the lifter 27. The lifter 27 lowers the plurality of upright substrates 9 and immerses them in the substitute liquid stored in the processing bath 231 of the third processing unit 23. This supplies the substitute liquid to the entire surface of each substrate 9 (step S13). In the substrate processing apparatus 1a, the plurality of substrates 9 are immersed in the substitute liquid for a predetermined time in the third processing unit 23, which is a substitute liquid supply unit, thereby performing a substitution process of replacing the rinse liquid on the substrates 9 with the substitute liquid (i.e., a substitution process of replacing the rinse liquid in contact with the surfaces of the substrates 9 with the substitute liquid).

[0111] When the above-mentioned replacement process is completed, the lifter 27 lifts the plurality of substrates 9 from the processing tank 231 of the third processing unit 23 and transports them to the fourth processing unit 24. Then, the lifter 27 lowers the plurality of substrates 9 and immerses them in the drying processing liquid stored in the processing tank 241 of the fourth processing unit 24. This causes the drying processing liquid to be supplied to the entire surface of each substrate 9 (step S14). In other words, the replacement liquid in contact with the surface of the substrate 9 is replaced with the drying processing liquid.

[0112] As described above, the drying treatment liquid in the treatment tank 241 is preheated so that the temperature of the liquid when it contacts the surface of the substrate 9 is a predetermined contact temperature. The contact temperature is equal to or higher than the boiling point of the rinsing liquid and lower than the boiling point of the drying treatment liquid. The difference between the contact temperature and the boiling point of the drying treatment liquid is preferably, for example, 65°C or less.

[0113] In the substrate processing apparatus 1a, in the fourth processing unit 24, which is a drying processing liquid supply unit, a plurality of substrates 9 are immersed in the drying processing liquid at the contact temperature for a predetermined contact time (preferably 10 seconds or more), whereby molecules of the drying processing liquid are adsorbed to the surfaces of the substrates 9 and the pattern surfaces on the surfaces of the substrates 9. Note that the fourth processing unit 24 may be provided with a heating unit (e.g., an electric wire heater) (not shown) that heats the processing bath 241, and the drying processing liquid supplied to the processing bath 241 (i.e., the drying processing liquid after contacting the surfaces of the substrates 9) may be heated to the contact temperature. In this case, the temperature of the drying processing liquid supplied to the processing bath 241 may be room temperature or may be a temperature between room temperature and the contact temperature.

[0114] After the entire surfaces of the substrates 9 have been brought into contact with the drying treatment liquid at the contact temperature and the aforementioned contact time has elapsed, the lifter 27 lifts the substrates 9 from the treatment bath 241 of the fourth treatment unit 24 and transfers them to the substrate transfer mechanism 114a. The substrate transfer mechanism 114a transfers the substrates 9 to the fifth treatment unit 25 and transfers them to the substrate holder 252 of the fifth treatment unit 25. In the fifth treatment unit 25, which is a drying treatment unit, a drying treatment is performed on the upright substrates 9 (i.e., the liquid drying treatment liquid is removed from the surfaces of the substrates 9) (step S15). In the substrate processing apparatus 1a, the use of the aforementioned drying treatment liquid prevents the pattern from collapsing during the drying treatment, as described above.

[0115] After step S15 (drying process of substrate 9) is completed, the substrate 9 is heated by the substrate heating unit 253, thereby removing molecules of the drying process liquid adsorbed to the pattern on the substrate 9 (step S16). In the adsorbed molecule removal process of step S16, the temperature of the substrate 9 (i.e., the molecule removal temperature) is set to a temperature higher than the contact temperature and the boiling point of the drying process liquid. The molecules of the drying process liquid removed from the substrate 9 in step S16 are not the liquid drying process liquid, but a small number of molecules that remain adsorbed on the substrate 9 after the liquid drying process liquid is removed from the substrate 9 in the drying process of step S15. After step S16 is completed, the substrate transport mechanism 114a removes the plurality of substrates 9 from the fifth processing unit 25 and transports them out of the substrate processing apparatus 1a, which is a processing unit.

[0116] In the above example, the adsorbed molecule removal process in step S16 is performed in the same chamber 11a as the processes in steps S11 to S15, but this is not limiting. For example, after step S15 is completed, the substrates 9 may be unloaded from chamber 11a, and the adsorbed molecule removal process for the substrates 9 may be performed in another device by ashing using plasma or the like.

[0117] Furthermore, in the substrate processing apparatus 1a, as in the substrate processing apparatus 1, step S13 may be omitted.

[0118] As described above, the substrate processing method for processing the substrate 9 includes the steps of supplying a chemical liquid to the surface of the substrate 9 (step S11), supplying a rinse liquid to the surface of the substrate 9 after step S11 (step S12), contacting the surface of the substrate 9 with a heated drying treatment liquid after step S12 (step S14), and drying the substrate 9 by removing the drying treatment liquid from the surface of the substrate 9 after step S14 (step S15). The surface tension of the drying treatment liquid is lower than that of the rinse liquid. The boiling point of the drying treatment liquid is higher than that of the rinse liquid. The temperature of the drying treatment liquid that contacts the surface of the substrate 9 in step S14 is a predetermined contact temperature that is equal to or higher than the boiling point of the rinse liquid and lower than the boiling point of the drying treatment liquid. This can prevent pattern collapse during the drying treatment in step S15. Furthermore, the time from the start of supplying the drying treatment liquid to the substrate 9 until the substrate 9 comes into contact with the drying treatment liquid at the contact temperature can be shortened compared to, for example, supplying the drying treatment liquid at room temperature to the substrate 9 and then heating it to the contact temperature. As a result, the time required to process the substrate 9 can be shortened.

[0119] As described above, the drying treatment liquid preferably contains a fluorine-containing alcohol. As a result, as described above, in step S14, -OH of the drying treatment liquid bonds with oxygen atoms (O) on the pattern surface, and molecules of the drying treatment liquid are adsorbed to the pattern surface. As a result, the pattern surface is covered with molecules of the drying treatment liquid. Therefore, compared with when the drying treatment liquid is not adsorbed on the pattern surface, the surface free energy of the pattern is reduced, and the contact angle of the drying treatment liquid with respect to the pattern surface increases and approaches 90°. As a result, the capillary force acting between the patterns is reduced, thereby further suppressing collapse of the pattern during the drying treatment in step S15.

[0120] The fluorine-containing alcohol preferably has -CF2H at the end. This allows the pattern surface to be covered with -CF2H present at the end of the molecules of the drying treatment liquid. The -CF2H at the molecular end has a significant effect of reducing surface free energy. This further suppresses the collapse of the pattern during the drying treatment in step S15.

[0121] It is also preferable that the fluorine-containing alcohol has -CF3 at the end. This results in the pattern surface being covered with -CF3 present at the end of the molecules of the drying treatment liquid. The -CF3 at the molecular end has a significant effect of reducing surface free energy, similar to -CF2H. Therefore, collapse of the pattern during the drying treatment in step S15 can be further suppressed.

[0122] As described above, the number of C's contained in the molecular formula of the fluorine-containing alcohol is preferably 4 or more. As shown in the experimental results of Fig. 7, when the number of C's is 4 or more (Example 1), pattern collapse can be further suppressed compared to when the number of C's is less than 4 (Example 2).

[0123] The above-described substrate processing method preferably further includes, after step S15, a step (step S16) of heating the substrate 9 to remove molecules of the drying processing liquid adsorbed on the surface of the substrate 9. By removing unnecessary adsorbed substances on the surface of the substrate 9 in this manner, the cleanliness of the substrate 9 can be improved.

[0124] As described above, it is preferable that step S16 (adsorbed molecule removal process) and step S15 (drying process) are performed in the same chamber 11, 11a, thereby shortening the time required to process the substrate 9 in steps S11 to S16.

[0125] The above-described substrate processing method preferably further includes a step (step S13) between step S12 (supply of rinsing liquid) and step S14 (supply of drying processing liquid) of supplying a replacement liquid to the surface of the substrate 9 to replace the rinsing liquid in contact with the surface of the substrate 9 with the replacement liquid. In this case, in step S14, the replacement liquid in contact with the surface of the substrate 9 is replaced with the drying processing liquid. This makes it possible to avoid direct contact between the rinsing liquid and the drying processing liquid on the substrate 9. Therefore, even if the affinity between the rinsing liquid and the drying processing liquid is relatively low, the processing liquid in contact with the surface of the substrate 9 can be smoothly changed from the rinsing liquid to the drying processing liquid while preventing liquid splashing and the like caused by the direct contact.

[0126] As described above, in step S14, it is preferable that the drying processing liquid preheated to the contact temperature is supplied to the surface of the substrate 9. This can further shorten the time required to process the substrate 9.

[0127] As described above, in step S14, it is also preferable to heat the drying treatment liquid after it has come into contact with the surface of the substrate 9, thereby raising the temperature of the drying treatment liquid to the contact temperature. This improves the in-plane temperature uniformity of the drying treatment liquid on the surface of the substrate 9. In other words, it is possible to reduce temperature differences due to differences in position on the surface of the substrate 9. As a result, it is possible to improve the in-plane uniformity of the adsorption of molecules of the drying treatment liquid onto the pattern surface on the substrate 9. Therefore, it is possible to suppress collapse of the pattern approximately uniformly over the entire surface of the substrate 9.

[0128] As described above, it is preferable that the difference between the contact temperature and the boiling point of the drying treatment liquid is 65°C or less (for example, Examples 3 and 4 in FIG. 7). This allows the molecules of the drying treatment liquid to be efficiently adsorbed onto the pattern. As a result, pattern collapse can be further suppressed compared to when the difference between the contact temperature and the boiling point of the drying treatment liquid is greater than 65°C (Example 5).

[0129] As described above, in step S14, the contact time of the drying treatment liquid at the contact temperature with the surface of the substrate 9 is preferably 10 seconds or more. This allows molecules of the drying treatment liquid to be suitably adsorbed onto the pattern surface on the substrate 9. As a result, collapse of the pattern during the drying treatment in step S15 can be further suppressed.

[0130] The substrate processing apparatus 1, 1a described above includes a chemical liquid supply unit (first nozzle 51 or first processing unit 21 in the above example) that supplies a chemical liquid to the surface of the substrate 9, a rinse liquid supply unit (second nozzle 52 or second processing unit 22 in the above example) that supplies a rinse liquid to the surface of the substrate 9, a drying processing liquid supply unit (fourth nozzle 54 or fourth processing unit 24 in the above example) that supplies a heated drying processing liquid to the surface of the substrate 9, and a drying processing unit (substrate rotation mechanism 33 or fifth processing unit 25 in the above example) that dries the substrate 9 by removing the drying processing liquid from the surface of the substrate 9. The surface tension of the drying processing liquid is lower than that of the rinse liquid. The boiling point of the drying processing liquid is higher than that of the rinse liquid. The temperature of the drying processing liquid that comes into contact with the surface of the substrate 9 is a predetermined contact temperature that is equal to or higher than the boiling point of the rinse liquid and lower than the boiling point of the drying processing liquid. This makes it possible to prevent pattern collapse during the drying process, as described above.

[0131] As described above, the drying treatment liquid preferably contains a fluorine-containing alcohol, which can further prevent the pattern from collapsing during the drying treatment in step S15, as described above.

[0132] The drying processing liquid is particularly suitable for substrate processing that requires prevention of pattern collapse during drying processing.

[0133] The above-described substrate processing apparatus 1, 1a, substrate processing method, and drying processing solution can be modified in various ways.

[0134] For example, the drying treatment liquid is not limited to the first drying treatment liquid and the second drying treatment liquid described above, and may contain other types of fluorine-containing alcohols having -CF2H at the terminal. Alternatively, the drying treatment liquid may contain various types of fluorine-containing alcohols having -CF3 at the terminal, as described above. Furthermore, the drying treatment liquid may contain various types of fluorine-containing alcohols having a structure other than -CF2H and -CF3 at the terminal. The number of C's contained in the molecular formula of the fluorine-containing alcohol may be 3 or less, or 8 or more. The drying treatment liquid may not contain a fluorine-containing alcohol.

[0135] In step S14, the contact time of the drying treatment liquid at the contact temperature with the surface of the substrate 9 may be less than 10 seconds. The difference between the contact temperature and the boiling point of the drying treatment liquid may be greater than 65°C.

[0136] In the substrate processing apparatus 1, in the drying process of step S15, the removal of the drying treatment liquid from the substrate 9 does not necessarily have to be performed by rotating the substrate 9 alone, but may be achieved by various methods. For example, by heating the substrate 9 to a temperature equal to or higher than the boiling point of the drying treatment liquid, the portion of the drying treatment liquid on the substrate 9 that is in contact with the substrate 9 is vaporized to form a gas layer, and nitrogen gas or the like is injected into the center of the liquid film of the drying treatment liquid supported on the gas phase to open a hole in the center of the liquid film. Then, by further injecting nitrogen gas and rotating the substrate 9, the hole is enlarged radially outward, and the liquid drying treatment liquid may be removed from the substrate 9.

[0137] After step S15 is completed, if the molecules of the drying processing liquid adsorbed on the pattern surface do not substantially adversely affect the quality of the substrate 9, the adsorbed molecule removal process in step S16 may be omitted.

[0138] The above steps S11 to S16 may be performed in an apparatus having a structure other than that of the substrate processing apparatus 1, 1a. The drying processing liquid may also be used in an apparatus having a structure other than that of the substrate processing apparatus 1, 1a.

[0139] The above-described substrate processing apparatus 1, 1a may be used to process glass substrates used in flat panel displays such as liquid crystal displays or organic EL (Electro Luminescence) displays, or glass substrates used in other displays, in addition to semiconductor substrates. The above-described substrate processing apparatus 1 may also be used to process substrates for optical disks, magnetic disks, magneto-optical disks, photomasks, ceramic substrates, and solar cell substrates.

[0140] The configurations of the above-described embodiment and each modification may be combined as appropriate as long as they are not mutually contradictory. [Explanation of symbols]

[0141] 1, 1a Substrate processing equipment 9 Substrate 11,11a Chamber 21 First Processing Section 22 Second Processing Section 23 Third Processing Section 24 4th Processing Section 25 5th Processing Section 33 Substrate rotation mechanism 51 No. 1 nozzle 52 Second nozzle 53 Third nozzle 54 No. 4 nozzle 91 (board) top surface 92 (board) bottom J1 center axis Steps S11 to S16

Claims

1. A substrate processing method for processing a substrate, comprising: a) supplying a chemical solution to a surface of a substrate; b) supplying a rinse liquid to the surface of the substrate after the step a); c) contacting the surface of the substrate with a heated drying treatment liquid after the b) step; d) drying the substrate by removing the drying treatment liquid from the surface of the substrate after the step c); Equipped with the surface tension of the drying treatment liquid is lower than the surface tension of the rinse liquid; the boiling point of the drying treatment liquid is higher than the boiling point of the rinse liquid; the temperature of the drying treatment liquid that comes into contact with the surface of the substrate in the step c) is a predetermined contact temperature that is equal to or higher than the boiling point of the rinsing liquid and lower than the boiling point of the drying treatment liquid; a drying treatment liquid contacting the surface of the substrate and then heating the drying treatment liquid to the contact temperature in the step c);

2. 2. The substrate processing method according to claim 1, e) after the step d), further comprising the step of heating the substrate to remove molecules of the drying processing liquid adsorbed on the surface of the substrate.

3. 3. The substrate processing method according to claim 2, a substrate processing method, wherein the steps d) and e) are performed in the same chamber;

4. 4. The substrate processing method according to claim 1, further comprising: between the step b) and the step c), a step of supplying a replacement liquid to the surface of the substrate and replacing the rinse liquid in contact with the surface of the substrate with the replacement liquid, A substrate processing method, wherein in the step c), the substitute liquid in contact with the surface of the substrate is replaced with the dry processing liquid.

5. 5. The substrate processing method according to claim 1, further comprising: A substrate processing method, wherein the difference between the contact temperature and the boiling point of the drying processing liquid is 65° C. or less.

6. 6. The substrate processing method according to claim 1, further comprising: A substrate processing method, wherein in the step c), the contact time of the drying processing liquid at the contact temperature with the surface of the substrate is 10 seconds or more.

7. 7. A substrate processing method according to claim 1, further comprising:

2. A substrate processing method, wherein the drying processing liquid contains a fluorine-containing alcohol.

8. 8. The substrate processing method according to claim 7, The fluorine-containing alcohol has a terminal group of —CF ２ A substrate processing method comprising:

9. 8. The substrate processing method according to claim 7, The fluorine-containing alcohol has a terminal group of —CF ３ A substrate processing method comprising:

10. 10. The substrate processing method according to claim 7, further comprising: A substrate processing method, wherein the number of carbon atoms contained in the molecular formula of the fluorine-containing alcohol is 4 or more.

11. A substrate processing apparatus for processing a substrate, a chemical supply unit that supplies a chemical solution to the surface of the substrate; a rinse liquid supply unit that supplies a rinse liquid to the surface of the substrate; a drying treatment liquid supply unit that supplies a heated drying treatment liquid to the surface of the substrate; a drying processing unit that dries the substrate by removing the drying processing liquid from the surface of the substrate; a substrate heating unit that heats the substrate; Equipped with the surface tension of the drying treatment liquid is lower than the surface tension of the rinse liquid; the boiling point of the drying treatment liquid is higher than the boiling point of the rinse liquid; the temperature of the drying treatment liquid in contact with the surface of the substrate is a predetermined contact temperature that is equal to or higher than the boiling point of the rinsing liquid and lower than the boiling point of the drying treatment liquid; a substrate heating section for heating the drying treatment liquid after contacting the surface of the substrate, thereby raising the temperature of the drying treatment liquid to the contact temperature;

12. The substrate processing apparatus according to claim 11, 4. The substrate processing apparatus according to claim 1, wherein the drying processing liquid contains a fluorine-containing alcohol.

13. A dry processing liquid used in processing a substrate, comprising: The substrate processing method using the dry processing liquid includes: a) supplying a chemical solution to a surface of a substrate; b) supplying a rinse liquid to the surface of the substrate after the step a); c) contacting the heated drying treatment liquid with the surface of the substrate after the step b); d) drying the substrate by removing the drying treatment liquid from the surface of the substrate after the step c); Equipped with the drying treatment liquid contains a fluorine-containing alcohol, the surface tension of the drying treatment liquid is lower than the surface tension of the rinse liquid; the boiling point of the drying treatment liquid is higher than the boiling point of the rinse liquid; the temperature of the drying treatment liquid that comes into contact with the surface of the substrate in the step c) is a predetermined contact temperature that is equal to or higher than the boiling point of the rinsing liquid and lower than the boiling point of the drying treatment liquid; The drying treatment liquid, wherein in the step c), the drying treatment liquid is heated after contacting the surface of the substrate, so that the temperature of the drying treatment liquid is increased to the contact temperature.

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