Substrate processing apparatus, processing liquid, and substrate processing method

Abstract

A substrate processing apparatus (1) is provided with a substrate holding unit (2), a processing liquid supply unit, a heating unit (5), and a liquid removal unit. The substrate holding unit (2) holds the substrate (9) in a horizontal state. The processing liquid supply unit supplies a processing liquid having a higher surface tension than IPA to the upper surface (91) of the substrate (9), thereby forming a liquid film of the processing liquid covering the entire upper surface (91) of the substrate (9). The heating unit (5) heats the substrate (9) from the side of the lower surface (92) and vaporizes a portion of the liquid film, thereby forming a gas phase layer between the upper surface (91) of the substrate (9) and the liquid film. The liquid removal unit removes the liquid film on the gas phase layer. As a result, unexpected breakage of the liquid film can be suppressed.

Description

[0001] This application is a divisional application of the patent application with application number CN 201980049434.1, application date July 10, 2019, and invention name “Substrate processing device, processing liquid and substrate processing method”. Technical Field

[0002] The present invention relates to a substrate processing device for processing a substrate, a processing liquid used in the substrate processing device and a substrate processing method for processing a substrate. Background Art

[0003] Conventionally, various treatments are applied to semiconductor substrates (hereinafter referred to as "substrates") during the manufacturing process. For example, a chemical solution is sprayed from a nozzle onto a substrate having a resist pattern (i.e., a plurality of fine structures) formed on the surface, thereby performing chemical treatments such as etching on the surface of the substrate.

[0004] In addition, after the substrate is treated with a liquid chemical, a rinse process and a drying process are further performed. The rinse process is a process of supplying pure water to the substrate and removing the liquid chemical, and the drying process is a process of rotating the substrate at high speed and removing the liquid on the substrate. In the case where a fine pattern is formed on the substrate, when the rinse process and the drying process are performed in sequence, a pure water liquid surface is formed between two adjacent pattern elements during the drying process. In this case, there is a concern that the pattern elements may collapse due to the surface tension of the pure water acting on the pattern elements.

[0005] Therefore, in the substrate processing apparatuses of Japanese Patent Publication No. 2014-112652 (Document 1), Japanese Patent Publication No. 2016-136599 (Document 2), and Japanese Patent Publication No. 2016-162847 (Document 3), after performing the rinsing process, an IPA (isopropyl alcohol) liquid is supplied to the upper surface of the substrate and replaced with the rinsing liquid, thereby forming an IPA liquid film on the substrate. Next, the substrate is heated and an IPA vapor film is formed between the IPA liquid film and the upper surface of the substrate, thereby causing the IPA liquid film to float from the upper surface of the substrate, and then the liquid film is removed from the substrate. When removing the liquid film from the substrate, nitrogen gas is sprayed from the nozzle to the center of the liquid film and the liquid film is locally removed, thereby forming a small-diameter dry area; and nitrogen gas is further sprayed to the center while the substrate is rotated, thereby expanding the dry area and extending it to the entire upper surface of the substrate. Thus, the upper surface of the substrate is dried while suppressing the collapse of pattern elements.

[0006] In addition, in the substrate processing device of document 3, when removing the liquid film from the substrate, after forming a dry area in the center of the liquid film, an inactive gas is ejected from a circumferential slit opening provided on the outer peripheral surface of the nozzle. Thus, a radial airflow is formed from the nozzle toward obliquely downward, and the expansion of the dry area is promoted by the airflow.

[0007] However, in a substrate processing device, there is a concern about unexpected damage to the IPA liquid film when it is formed and heated (that is, before the removal of the IPA liquid film begins). Specifically, there may be a situation where the IPA flows down from the periphery of the substrate or the contact portion between the chuck pin and the liquid film. Alternatively, there may be a situation where cracks are generated in the liquid film due to the IPA vapor generated under the IPA liquid film. In this way, there is a possibility that the time for heating the IPA liquid film is reduced. From the perspective of fully floating and removing the IPA liquid film from the upper surface of the substrate through the vapor film, it is better to ensure that the heating time of the IPA liquid film is above a certain level. Summary of the invention

[0008] The present invention focuses on a substrate processing apparatus for processing a substrate, and aims to suppress unexpected damage to a liquid film.

[0009] A substrate processing device in a preferred embodiment of the present invention comprises: a substrate holding portion for holding a substrate in a horizontal state; a processing liquid supply portion for supplying a processing liquid having a surface tension higher than that of isopropyl alcohol to the upper surface of the substrate, thereby forming a liquid film of the processing liquid covering the entire upper surface of the substrate; a heating portion for heating the substrate from the lower surface side and vaporizing a portion of the liquid film, thereby forming a gas phase layer between the upper surface of the substrate and the liquid film; and a liquid removal portion for removing the liquid film on the gas phase layer. According to the substrate processing device, unexpected damage to the liquid film can be suppressed.

[0010] Preferably, the vapor pressure of the treatment liquid is higher than the vapor pressure of isopropyl alcohol.

[0011] Preferably, the treatment liquid includes at least one of cis-1,2-dichloroethylene, trichloromethane, methyl acetate, 1,3-dioxolane, tetrahydrofuran, 1,1,1-trichloroethane, tetrachloromethane, benzene, cyclohexane, acetonitrile, trichloroethylene, tetrahydropyran, nitric acid, 1,2-dichloroethane, 1,2-dichloropropane, fluorotrinitromethane, pyrrolidine, acrylonitrile, and cyclohexene.

[0012] Preferably, the heating of the substrate by the heating unit starts after the entire upper surface of the substrate is covered with the processing liquid supplied from the processing liquid supply unit.

[0013] Preferably, the processing liquid is supplied to the upper surface of the substrate from the processing liquid supply part while the entire upper surface of the substrate is covered with isopropyl alcohol, and the isopropyl alcohol on the upper surface of the substrate is replaced by the processing liquid, thereby forming the liquid film of the processing liquid.

[0014] Preferably, the treatment liquid is a mixed liquid obtained by mixing a substance having a higher surface tension than isopropyl alcohol and a lower vapor pressure than isopropyl alcohol with isopropyl alcohol.

[0015] Preferably, the liquid removal portion comprises: a gas ejection portion, which ejects gas toward a central portion of the liquid film; and a radial airflow is formed from the central portion of the liquid film toward the surroundings by the gas from the gas ejection portion, so that the processing liquid moves from the central portion of the liquid film toward the outer edge of the substrate and is removed from the substrate.

[0016] Preferably, the gas ejection portion comprises: a first ejection port ejecting gas toward the central portion of the liquid film; and a plurality of second ejection ports circumferentially arranged around the first ejection port ejecting gas radially from the central portion of the liquid film toward the periphery.

[0017] Preferably, the substrate processing device further comprises: a chamber, in which the substrate holding part is housed, and an airflow forming part, which sends gas from the upper part of the chamber to the inner space and forms a downward airflow from the upper side to the lower side of the substrate around the substrate. The downward airflow promotes the movement of the processing liquid in the peripheral part of the upper surface of the substrate toward the outer edge when removing the processing liquid from the substrate.

[0018] Preferably, the substrate processing device further comprises: a rotating mechanism for rotating the substrate holding part; a cup arranged around the substrate holding part with a gap therebetween for catching liquid scattered from the rotating substrate; and a cup moving mechanism for relatively moving the cup with respect to the substrate holding part. When removing the processing liquid from the substrate, the cup is relatively moved by the cup moving mechanism to reduce the gap between the substrate holding part and the cup.

[0019] Preferably, when the heating unit starts heating the substrate, the airflow forming unit stops forming the downward airflow.

[0020] Preferably, before the heating unit starts heating the substrate, the processing liquid supply unit stops supplying the processing liquid, and at the same time, the airflow formation unit stops forming the descending airflow.

[0021] Preferably, the airflow formation section starts to form the downward airflow again after the temperature of the peripheral portion of the substrate becomes equal to or higher than a predetermined temperature.

[0022] The present invention also focuses on a processing liquid used in processing a substrate. In a preferred embodiment of the present invention, the processing liquid has a surface tension higher than that of isopropyl alcohol and is supplied to the upper surface of the substrate in the substrate processing apparatus.

[0023] The present invention also focuses on a substrate processing method for processing a substrate. A preferred substrate processing method of the present invention comprises: step (a), maintaining the substrate in a horizontal state; step (b), supplying a processing liquid having a surface tension higher than isopropyl alcohol to the upper surface of the substrate, thereby forming a liquid film of the processing liquid covering the entire upper surface of the substrate; step (c), heating the substrate from the lower surface side and vaporizing a portion of the liquid film, thereby forming a gas phase layer between the upper surface of the substrate and the liquid film; and step (d), removing the liquid film on the gas phase layer. According to this substrate processing method, unexpected damage to the liquid film can be suppressed.

[0024] The object and other objects, features, aspects and advantages of the present invention will become clear from the following detailed description of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a side view of a substrate processing apparatus according to one embodiment.

[0026] Figure 2 It is a block diagram showing a liquid supply unit and a gas supply unit.

[0027] Figure 3 It is a side view showing the first nozzle in an enlarged manner.

[0028] Figure 4 It is a diagram showing the flow of processing of a substrate.

[0029] Figure 5 This is a diagram showing a substrate being processed and a part of a substrate processing apparatus.

[0030] Figure 6 This is a diagram showing a substrate being processed and a part of a substrate processing apparatus.

[0031] Figure 7 It is a longitudinal sectional view showing the vicinity of the upper surface of the substrate in an enlarged manner.

[0032] Figure 8 It is a longitudinal sectional view showing the vicinity of the upper surface of the substrate in an enlarged manner.

[0033] Fig. 9 It is a diagram showing the process flow of substrate processing.

[0034] Fig.10 This is a diagram showing a substrate being processed and a part of a substrate processing apparatus.

[0035] Fig.11 This is a diagram showing a substrate being processed and a part of a substrate processing apparatus.

[0036] Fig.12 This is a diagram showing a substrate being processed and a part of a substrate processing apparatus. DETAILED DESCRIPTION

[0037] Figure 1 1 is a side view showing the structure of a substrate processing apparatus 1 according to one embodiment of the present invention. The substrate processing apparatus 1 is a single-sheet type apparatus for processing semiconductor substrates 9 (hereinafter referred to as "substrates 9") one by one. The substrate processing apparatus 1 supplies a chemical solution to the substrate 9 having a fine pattern formed on its upper surface 91 and performs liquid processing. Figure 1 1 and 2 show a part of the structure of the substrate processing apparatus 1 in cross section.

[0038] The substrate processing apparatus 1 includes a substrate holding portion 2, a rotating mechanism 3, a cup portion 4, a heating portion 5, a liquid supply portion 6, a gas supply portion 7, and a chamber 11. The substrate holding portion 2, the rotating mechanism 3, the cup portion 4, the heating portion 5, a portion of the liquid supply portion 6, and a portion of the gas supply portion 7 are accommodated in an internal space of the chamber 11.

[0039] The substrate holding part 2 is a mechanical chuck that directly contacts the peripheral portion of the substrate 9 and fixes the position of the substrate 9. The substrate 9 is held in a horizontal state by the substrate holding part 2. The rotation mechanism 3 rotates the substrate 9 and the substrate holding part 2 around the central axis J1 in the vertical direction. The rotation mechanism 3 is, for example, an electric motor. The substrate holding part 2 and the rotation mechanism 3 constitute a spin chuck for holding the substrate 9 and rotating the substrate 9.

[0040] The substrate holding portion 2 includes a base portion 21, a holding shaft portion 22, and a plurality of chuck pins 23. The base portion 21 is a roughly disk-shaped portion with the center axis J1 as the center. The holding shaft portion 22 is a roughly cylindrical portion extending downward from the center portion of the base portion 21. The holding shaft portion 22 is accommodated in a roughly cylindrical cover portion 24, which is disposed below the base portion 21. A rotating mechanism 3 for rotating the holding shaft portion 22 is also accommodated in the cover portion 24. The diameter of the cover portion 24 is, for example, substantially the same as the diameter of the base portion 21.

[0041] A plurality of chuck pins 23 protrude upward from the upper surface of the base portion 21. The plurality of chuck pins 23 are arranged at substantially equal angle intervals in a circumferential direction (hereinafter also referred to as "circumferential direction") with the central axis J1 as the center. The number of the plurality of chuck pins 23 is, for example, three or four. The substrate 9 is arranged above the base portion 21 at a position away from the upper surface of the base portion 21 by supporting the peripheral portion through the plurality of chuck pins 23.

[0042] The cup portion 4 includes a cup 41 and a cup moving mechanism 42. The cup 41 is arranged around the substrate 9 and the substrate holding portion 2 with a gap therebetween. The cup 41 receives liquids such as liquid medicine, rinse liquid and processing liquid that fly from the rotating substrate 9. The cup 41 includes a cup side wall portion 43 and a cup top cover portion 44. The cup side wall portion 43 is a roughly cylindrical portion with the central axis J1 as the center. The cup top cover portion 44 is a roughly annular portion with the central axis J1 as the center. The cup top cover portion 44 extends radially inward from the upper end portion of the cup side wall portion 43. Figure 1In the example shown, the inner side surface of the cup top cover 44 is an inclined surface that is inclined upward as it is radially inward. Liquid that is scattered radially outward from the peripheral edge of the rotating substrate 9, for example, collides with the inner side surface of the cup 41 and falls toward the bottom of the cup 41, and is discharged to the outside of the chamber 11 through a discharge port 45 provided at the bottom.

[0043] The cup moving mechanism 42 moves the cup 41 relative to the substrate holding portion 2. Figure 1 In the example shown, the cup moving mechanism 42 is a lifting mechanism for moving the cup 41 in the vertical direction. The cup moving mechanism 42 includes, for example, an air cylinder oriented in the vertical direction and a connecting member connecting the movable part of the air cylinder and the cup 41. In addition, the cup moving mechanism 42 is not necessarily a mechanism for moving the cup 41, but may be a mechanism for moving the substrate holding part 2 in the vertical direction.

[0044] The heating unit 5 includes a heating plate 51, a heating shaft 52, and a plate lifting mechanism 53. The heating plate 51 is a roughly circular plate-shaped portion with the central axis J1 as the center. The heating plate 51 is located between the base portion 21 of the substrate holding portion 2 and the substrate 9, and is opposite to the lower surface 92 of the substrate 9 in the up-down direction. The upper surface of the heating plate 51 is roughly parallel to the lower surface 92 of the substrate 9. The diameter of the upper surface of the heating plate 51 is slightly smaller than the diameter of the substrate 9. For example, when the diameter of the substrate 9 is 300 mm, the diameter of the upper surface of the heating plate 51 is 294 mm. A heater not shown in the figure is provided inside the heating plate 51.

[0045] The heating shaft 52 is a substantially cylindrical portion and is connected to the center of the heating plate 51. The heating shaft 52 extends downward from the heating plate 51 through the interior of the holding shaft 22. A plate lifting mechanism 53 is connected to the heating shaft 52. The plate lifting mechanism 53 is, for example, an electric motor. The heating shaft 52 is raised and lowered by the plate lifting mechanism 53, so that the heating plate 51 moves in the vertical direction between the base 21 and the substrate 9. Specifically, the heating plate 51 is moved upward and downward. Figure 1 The position indicated by the solid line in FIG. 1 (hereinafter referred to as the "standby position") and Figure 1 The heating device moves in the up-down direction between the positions indicated by the two-dot chain lines (hereinafter referred to as "heating positions").

[0046] The upper surface of the heating plate 51 at the heating position is in direct contact with the lower surface 92 of the substrate 9. Alternatively, the upper surface of the heating plate 51 at the heating position is separated from the lower surface 92 of the substrate 9 by an extremely small gap (for example, a gap of about 0.1 mm in height) and moves downward from the lower surface 92 of the substrate 9. In the heating plate 51 at the heating position, power is supplied to the built-in heater, thereby heating the substantially entire surface of the upper surface of the heating plate 51 approximately evenly, and also heating the substantially entire surface of the substrate 9 approximately evenly. The standby position described above is a position below the heating position. Since the heating plate 51 at the standby position moves downward from the lower surface 92 of the substrate 9 to a large extent, the substrate 9 is not heated. In addition, the heating plate 51 and the heating shaft 52 do not rotate.

[0047] Figure 2 1 is a block diagram showing the liquid supply unit 6 and the gas supply unit 7 of the substrate processing apparatus 1. Figure 2 The components other than the liquid supply unit 6 and the gas supply unit 7 are also shown. The liquid supply unit 6 supplies a plurality of liquids to the substrate 9 separately. The plurality of liquids include, for example, a chemical solution, a rinse solution, and a processing solution. Figure 1 as well as Figure 2 As shown, the liquid supply unit 6 includes a first nozzle 61, a second nozzle 62, and a third nozzle 63. The first nozzle 61, the second nozzle 62, and the third nozzle 63 respectively supply liquid from above the substrate 9 toward the upper surface 91 of the substrate 9. The gas supply unit 7 includes a gas flow forming unit 71. The first nozzle 61 described above is also included in the gas supply unit 7.

[0048] exist Figure 1 In the example shown, the first nozzle 61 can move between a processing position above the substrate 9 (for example, above the center of the substrate 9) and a retreat position radially outward from the outer edge of the substrate 9. The first nozzle 61 is moved by a first nozzle moving mechanism 610. The first nozzle moving mechanism 610 includes, for example, an arm that supports the first nozzle 61 and an electric motor that rotates and raises and lowers the arm extending laterally from the first nozzle 61.

[0049] Similar to the first nozzle 61, the second nozzle 62 can also move between a processing position above the substrate 9 (for example, above the center of the substrate 9) and a retreat position radially outward from the outer edge of the substrate 9. The second nozzle 62 is moved by a second nozzle moving mechanism 620. The second nozzle moving mechanism 620 includes, for example, an arm that supports the second nozzle 62 and an electric motor that rotates and raises and lowers the arm extending laterally from the second nozzle 62.

[0050] The third nozzle 63 is fixed above the substrate 9 with the liquid discharge port directed toward the center of the upper surface 91 of the substrate 9. Also, similarly to the first nozzle 61 and the second nozzle 62, the third nozzle 63 can also move between a processing position and a retreat position.

[0051] Figure 3 61. The first nozzle 61 includes a nozzle body 611, a process liquid flow path 612, a first gas flow path 613, and a second gas flow path 614. The nozzle body 611 is a substantially cylindrical member. The process liquid flow path 612, the first gas flow path 613, and the second gas flow path 614 are formed inside the nozzle body 611.

[0052] The ejection port 615 of the processing liquid flow path 612 is disposed at the central portion of the lower end surface of the nozzle body 611. The first ejection port 616 of the first gas flow path 613 is also disposed at the central portion of the lower end surface of the nozzle body 611. When the first nozzle 61 is located at the processing position, the ejection port 615 of the processing liquid flow path 612 and the first ejection port 616 of the first gas flow path 613 face the central portion of the upper surface 91 of the substrate 9 in the vertical direction.

[0053] The second gas flow path 614 is connected to a plurality of small second ejection ports 617, and the plurality of second ejection ports 617 are circumferentially arranged around the first ejection port 616. Figure 3 In the example shown, the plurality of second jet outlets 617 are arranged in a circumferential shape at approximately equal angles in the outer side surface of the first nozzle 61 at approximately the same position in the vertical direction. The plurality of second jet outlets 617 have approximately the same shape and size. The shape of each second jet outlet 617 when viewed from the side is, for example, approximately circular. The diameter of each second jet outlet 617 is, for example, smaller than the diameter of the first jet outlet 616, and is approximately 1 mm.

[0054] The processing liquid flow path 612 of the first nozzle 61 is connected via Figure 2 The pipe 641 and valve 642 shown are connected to the processing liquid supply source 64. When the first nozzle 61 is located at the processing position, the valve 642 is opened, thereby supplying the processing liquid from the processing liquid supply source 64 to the processing liquid flow path 612 via the pipe 641 and spraying the processing liquid from the spray port 615 toward the central part of the upper surface 91 of the substrate 9. The valve 642 is closed, thereby stopping the spraying of the processing liquid from the first nozzle 61. The first nozzle 61 is a processing liquid supply unit for supplying the processing liquid to the upper surface 91 of the substrate 9. The pipe 641 and the valve 642 may also be included in the processing liquid supply unit.

[0055] The surface tension of the processing liquid supplied from the first nozzle 61 to the substrate 9 is higher than the surface tension of isopropyl alcohol (molecular formula: C3H8O, hereinafter referred to as "IPA") at the same temperature. In addition, it is preferred that the vapor pressure of the processing liquid is higher than the vapor pressure of IPA at the same temperature. In other words, the boiling point of the processing liquid is lower than the boiling point of IPA at the same pressure. When describing the relationship between the surface tension, vapor pressure and boiling point of multiple liquids below, the surface tension, vapor pressure and boiling point of multiple liquids are set to be at the same temperature and the same pressure. In addition, the surface tension of IPA at room temperature (25°C) and normal pressure (100kPa) is 20.8mN / m, the vapor pressure of IPA at room temperature (25°C) and normal pressure (100kPa) is 5.87kPa, and the boiling point of IPA at room temperature (25°C) and normal pressure (100kPa) is 82.4°C. The surface tension of the processing liquid is lower than that of pure water, for example. In addition, the vapor pressure of the processing liquid is higher than that of pure water, for example.

[0056] Preferably, the treatment liquid includes cis-1,2-dichloroethylene (molecular formula: C2H2Cl2), chloroform (molecular formula: CHCl3), methyl acetate (molecular formula: C3H6O2), 1,3-dioxolane (molecular formula: C3H6O2), tetrahydrofuran (molecular formula: C4H8O), 1,1,1-trichloroethane (molecular formula: C2H3Cl3), tetrachloromethane (molecular formula: CCl4), benzene (molecular formula: C6H6), cyclohexane (molecular formula: C6H 12 ), acetonitrile (molecular formula: C2H3N), trichloroethylene (molecular formula: C2HCl3), tetrahydropyran (molecular formula: C5H 10 O), nitric acid (molecular formula: HNO3), 1,2-dichloroethane (molecular formula: C2H4Cl2), 1,2-dichloropropane (molecular formula: C3H6Cl2), fluorotrinitromethane (molecular formula: CFN3O6), pyrrolidine (molecular formula: C4H9N), acrylonitrile (molecular formula: C3H3N), cyclohexene (molecular formula: C6H 10 ) in at least one of the liquids.

[0057] The surface tension and vapor pressure of each liquid contained in the liquid group described above are higher than the surface tension and vapor pressure of IPA. In addition, the processing liquid may also be a mixture of two or more liquids in the liquid group described above. In addition, the processing liquid may also be a processing liquid in which one or more liquids in the liquid group described above are diluted with a solvent.

[0058] The first gas flow path 613 (see Figure 3 ) is connected to the gas supply source 74 via the pipe 741 and the valve 742. The second gas flow path 614 (see Figure 3) is connected to the gas supply source 74 via the piping 743 and the valve 744. When the first nozzle 61 is located at the processing position, the valve 742 is opened, thereby supplying gas from the gas supply source 74 to the first gas flow path 613 via the piping 741, and the gas is discharged from the first ejection port 616 (see Figure 3 ) is ejected toward the center of the upper surface 91 of the substrate 9. The valve 742 is closed, thereby stopping the ejection of gas from the first ejection port 616. In addition, the valve 744 is opened, thereby supplying gas from the gas supply source 74 to the second gas flow path 614 via the pipe 743, and ejecting gas from the plurality of second ejection ports 617 (see Figure 3 ) is radially ejected in an inclined direction (that is, inclined downward toward the radial outside) from the center of the upper surface 91 of the substrate 9. The valve 744 is closed, thereby stopping the ejection of gas from the second ejection port 617.

[0059] As described above, the first nozzle 61 is a gas ejection portion, and includes a first ejection port 616 and a plurality of second ejection ports 617. The gas ejection portion may also include pipes 741, 743 and valves 742, 744. In the first nozzle 61, ejection of gas from the first ejection port 616 and stopping of ejection of gas from the first ejection port 616 and ejection of gas from the second ejection port 617 and stopping of ejection of gas from the second ejection port 617 can be controlled separately. In addition, the flow rate of the gas ejected from the first ejection port 616 and the flow rate of the gas ejected from the second ejection port 617 can be controlled separately. The gas delivered from the gas supply source 74 to the first nozzle 61 is preferably an inert gas (such as nitrogen (N2), argon (Ar) or a clean dry gas, etc.). Figure 1 In the illustrated example, nitrogen is ejected from the first ejection port 616 and the second ejection port 617 of the first nozzle 61. The gas ejected from the first nozzle 61 may be a gas other than the inert gas.

[0060] The second nozzle 62 is connected to the liquid supply source 65 via the piping 651 and the valve 652. When the second nozzle 62 is located at the processing position, the valve 652 is opened, thereby supplying the processing liquid from the liquid supply source 65 to the second nozzle 62 via the piping 651 and spraying it toward the central part of the upper surface 91 of the substrate 9. The valve 652 is closed to stop the liquid from being sprayed from the second nozzle 62. The liquid is a liquid such as an acid or an alkali. The liquid is, for example, an etching liquid or a cleaning liquid. Specifically, hydrofluoric acid, SC1 (standard clean-1; the first standard rinse liquid; that is, a mixture of ammonia and hydrogen peroxide water), SC2 (standard clean-2; the second standard rinse liquid; that is, a mixture of hydrochloric acid and hydrogen peroxide water), or buffered hydrofluoric acid (buffered HF; that is, a mixture of hydrofluoric acid and ammonium fluoride) is used as the liquid.

[0061] The third nozzle 63 is connected to the rinse liquid supply source 66 via the pipe 661 and the valve 662. The valve 662 is opened, so that the rinse liquid is supplied from the rinse liquid supply source 66 to the third nozzle 63 via the pipe 661 and sprayed toward the center of the upper surface 91 of the substrate 9. The valve 662 is closed, so that the spraying of the rinse liquid from the third nozzle 63 is stopped. For example, DIW (De-ionized Water), carbonated water, ozone water, or hydrogen water is used as the rinse liquid. Figure 1 In the example shown, DIW is used as the rinse liquid.

[0062] like Figure 1 As shown in FIG. 1 , the air flow forming section 71 includes a fan unit 72 disposed at the upper portion of the chamber 11 (that is, at a position above the substrate holding section 2 and the cup section 4). Figure 1 In the example shown, the fan unit 72 is provided on the top cover of the chamber 11. The fan unit 72 is provided via Figure 2 The piping 751 and valve 752 shown are connected to another gas supply source 75 that is different from the gas supply source 74. The valve 752 is opened, thereby supplying gas from the gas supply source 75 to the fan unit 72 via the piping 751 and sending it downward in the internal space of the chamber 11. The valve 752 is closed, thereby stopping the gas from the fan unit 72. The gas sent from the gas supply source 75 to the fan unit 72 is, for example, a clean gas (i.e., air filtered through a filter). The gas may also be an inert gas such as nitrogen or argon. Figure 1 In the example shown, clean gas is sent out from the fan unit 72 .

[0063] The gas sent from the fan unit 72 flows downward through the upper opening of the cup 41 in the cup 41, and forms a downward airflow (so-called downflow) from the upper side to the lower side of the substrate 9 around the substrate 9. The gas reaching the bottom of the cup 41 is discharged to the outside of the chamber 11 through the exhaust port 45. The exhaust port 45 is connected to a suction mechanism (not shown) arranged outside the chamber 11, for example. In the substrate processing apparatus 1, the suction mechanism and the exhaust port 45 are also included in the airflow forming part 71 for forming the downward airflow.

[0064] Next, refer to Figure 4 An example of a process flow of processing the substrate 9 by the substrate processing apparatus 1 is described. When processing the substrate 9 in the substrate processing apparatus 1, first, the substrate 9 carried into the chamber 11 is held in a horizontal state by the substrate holding portion 2 (step S11). Clean air is sent into the chamber 11 from the fan unit 72, thereby forming the descending airflow described above around the substrate 9. The supply of clean gas from the fan unit 72 continues until the supply of the processing liquid is stopped in step S15 described later, so as to maintain the descending airflow.

[0065] Next, the rotating mechanism 3 starts to rotate the substrate 9, and the substrate 9 rotates at a predetermined rotation speed. In addition, the second nozzle 62 is moved toward the processing position by the second nozzle moving mechanism 620. In addition, the first nozzle 61 is located at the retreat position. Next, the second nozzle 62 starts to supply the chemical liquid to the rotating substrate 9. The chemical liquid supplied to the central portion of the upper surface 91 of the substrate 9 moves radially outward by centrifugal force and spreads to the entire upper surface 91 of the substrate 9. The chemical liquid that reaches the peripheral portion of the substrate 9 is scattered radially outward from the peripheral portion, as shown in FIG. Figure 1 The chemical is received by the cup 41 surrounding the substrate 9 and discharged to the outside of the chamber 11 through the discharge port 45. The chemical liquid is supplied to the substrate 9 for a predetermined time, thereby completing the chemical liquid treatment on the substrate 9 (step S12).

[0066] When the liquid medicine treatment is finished, the supply of liquid medicine to the substrate 9 is stopped, and the second nozzle 62 moves from the treatment position to the retreat position. In addition, the rinsing liquid starts to be supplied to the rotating substrate 9 from the third nozzle 63. The rinsing liquid supplied to the central portion of the upper surface 91 of the substrate 9 moves radially outward by centrifugal force and spreads to the entire upper surface 91 of the substrate 9. Thus, the liquid medicine on the upper surface 91 of the substrate 9 is washed away and removed from the substrate 9. The rinsing liquid that reaches the peripheral portion of the substrate 9 is scattered radially outward from the peripheral portion, is caught by the cup 41 surrounding the substrate 9, and is discharged to the outside of the chamber 11 through the discharge port 45. The rinsing liquid is supplied to the substrate 9 for a predetermined time, thereby completing the rinsing treatment of the substrate 9 (step S13).

[0067] When the rinsing treatment is completed, the supply of the rinsing liquid to the substrate 9 is stopped. In addition, the first nozzle 61 moves from the retreat position toward the treatment position, and the treatment liquid starts to be supplied from the first nozzle 61 to the rotating substrate 9. The treatment liquid supplied to the central portion of the upper surface 91 of the substrate 9 moves radially outward by centrifugal force and spreads to the entire upper surface 91 of the substrate 9. As a result, the rinsing liquid on the upper surface 91 of the substrate 9 is washed away and replaced by the treatment liquid. That is, the treatment liquid is a replacement liquid that replaces the rinsing liquid on the substrate 9. The treatment liquid that reaches the peripheral portion of the substrate 9 scatters radially outward from the peripheral portion, is caught by the cup 41 surrounding the substrate 9, and is discharged to the outside of the chamber 11 through the discharge port 45. The treatment liquid is supplied to the substrate 9 for a predetermined time, thereby completing the replacement treatment from the rinsing liquid to the treatment liquid.

[0068] When the replacement process is finished, the rotation mechanism 3 reduces the rotation speed of the substrate 9 and stops rotating the substrate 9 while the processing liquid is continuously supplied from the first nozzle 61. Figure 5As shown, a thick liquid film 93 of the processing liquid is formed covering the entire upper surface 91 of the stationary substrate 9 (step S14). In other words, the upper surface 91 of the substrate 9 is paddled with the processing liquid. In addition, the substrate 9 does not necessarily need to be stopped from rotating, and can be rotated at a relatively low rotation speed that appropriately maintains the liquid film 93 of the processing liquid on the substrate 9.

[0069] Next, the supply of the processing liquid from the first nozzle 61 to the substrate 9 is stopped (step S15). In addition, when the supply of the processing liquid is stopped, the fan unit 72 stops forming the downward airflow of the clean gas (step S16). Thus, the liquid film 93 of the processing liquid on the substrate 9 can be prevented from being disturbed by the downward airflow. In addition, the supply of the processing liquid can also be stopped until the heating plate 51 to be described next is about to start heating the substrate 9. Thus, the liquid film 93 of the processing liquid is appropriately maintained on the substrate 9.

[0070] Next, the preheated heating plate 51 is raised from the standby position toward the heating position by the plate lifting mechanism 53 of the heating unit 5, and the heating plate 51 starts to heat the substrate 9 (step S17). The heating of the heating plate 15 is performed on the substrate 9 in a stationary state. In addition, the heating of the heating plate 51 can also be performed on the substrate 9 rotating at a low speed. In this case, the heating plate 51 is away from the substrate 9 downward by a small distance. As described above, when the substrate 9 starts to be heated, the fan unit 72 stops forming a downward airflow. In addition, as described later, the formation of the downward airflow remains stopped until the substrate 9 is heated to a predetermined condition.

[0071] Next, the substrate 9 is heated from the lower surface 92 side by the heating plate 51, and the temperature of the upper surface 91 of the substrate 9 becomes higher than the boiling point of the processing liquid, whereby the processing liquid is vaporized in the portion of the liquid film 93 of the processing liquid that contacts the upper surface 91 of the substrate 9. In other words, a portion of the liquid film 93 of the processing liquid vaporizes on the upper surface 91 of the substrate 9. Figure 6 As shown in FIG. 1 , a gas phase layer 94 of the processing liquid is formed between the upper surface 91 of the substrate 9 and the liquid film 93 of the processing liquid (step S18). Figure 6 , the thickness of the gas phase layer 94 is depicted as being thicker than the actual thickness. The gas phase layer 94 is formed on the entire upper surface 91 of the substrate 9. As a result, the liquid film 93 of the processing liquid moves upward from the upper surface 91 of the substrate 9 and is supported from below by the gas phase layer 94. In other words, the liquid film 93 of the processing liquid is maintained in a state of floating on the upper surface 91 of the substrate 9 via the gas phase layer 94. In addition, the gas phase layer 94 of the processing liquid is also called a gas phase film, a vapor film, or a vapor layer of the processing liquid.

[0072] Figure 7 It is a longitudinal sectional view showing, in enlarged form, the vicinity of the upper surface 91 of the substrate 9 in a state where the liquid film 93 is formed in step S14 . Figure 8FIG. 2 is a longitudinal sectional view showing an enlarged view of the vicinity of the upper surface 91 of the substrate 9 in a state where the vapor phase layer 94 is formed in step S18. Figure 7 In the state shown, the spaces between the convex structures 911 forming the fine pattern provided on the substrate 9 are filled with the liquid film 93 of the processing liquid. In addition, the liquid film 93 of the processing liquid exists up to the upper side than the upper end of the structure 911 (that is, the upper surface 91 of the substrate 9). In other words, the upper surface of the liquid film 93 of the processing liquid is above the upper end of the structure 911.

[0073] As described above, when the substrate 9 is heated by the heating plate 51 to a temperature higher than the boiling point of the processing liquid (for example, a temperature 10°C to 50°C higher than the boiling point), the processing liquid in contact with the substrate 9 is gasified (i.e., evaporated) and generates gas of the processing liquid. Figure 8 As shown, a gas phase layer 94 is formed. The gas phase layer 94 fills the space between the structures 911 and further extends to the upper side than the upper end of the structures 911. Figure 8 In the state shown, the interface 95 between the gas phase layer 94 of the processing liquid and the liquid film 93 (i.e., the upper surface of the gas phase layer 94) is higher than the upper end of the structure 911. Therefore, the liquid film 93 of the processing liquid (i.e., the liquid processing liquid) moves upward from the structure 911 without contacting the structure 911.

[0074] In the substrate processing device 1, the fan unit 72 stops forming a downward airflow until the temperature of the peripheral portion of the substrate 9 becomes a predetermined temperature (for example, a temperature 10°C to 50°C higher than the boiling point of the processing liquid) or above. And, after a predetermined time has passed since the start of heating the substrate 9, and the temperature of the peripheral portion of the substrate 9 becomes above the predetermined temperature, the fan unit 72 starts to form a downward airflow again (step S19). In other words, in the peripheral portion of the substrate 9, after the gas phase layer 94 of the processing liquid is formed and the liquid film 93 moves upward from the structure 911, a downward airflow starts to be formed around the substrate 9 again. Thereby, the temperature of the processing liquid is prevented or suppressed from decreasing due to the downward airflow during the formation of the gas phase layer 94 in the peripheral portion of the substrate 9, thereby hindering the formation of the gas phase layer 94. In step S19, the temperature of the peripheral portion of the substrate 9 can also be measured by a temperature sensor, or the heating time until the temperature of the substrate 9 becomes above the predetermined temperature described above can be measured in advance, and it can be judged that the temperature of the peripheral portion of the substrate 9 has become above the predetermined temperature described above by the passage of this heating time.

[0075] When the gas phase layer 94 of the processing liquid is formed on the entire surface of the upper surface 91 of the substrate 9, the liquid film 93 on the gas phase layer 94 is removed from the substrate 9 (step S20). In step S20, the liquid film 93 of the processing liquid is removed from the substrate 9 while maintaining a state of not contacting the structure 911 on the substrate 9. Therefore, the processing liquid can be removed from the substrate 9 while preventing the structure 911 from collapsing due to the surface tension of the processing liquid.

[0076] The removal of the process liquid film 93 in step S20 can also be performed by various methods. Fig. 9 FIG. 1 is a diagram showing an example of a process for removing the liquid film 93. Fig. 9 In the steps S31 to S33 shown in FIG. 1 , the substrate 9 is not rotated but is in a stationary state. When removing the liquid film 93, first, after the above-mentioned step S19, an inert gas (for example, nitrogen) is ejected from the first ejection port 616 of the first nozzle 61 toward the central portion of the liquid film 93 located on the central portion of the substrate 9. Fig.10 As shown, a small hole 96 is formed in the center of the liquid film 93, and a portion of the upper surface 91 of the substrate 9 is exposed from the hole 96 (step S31). In step S31, the flow rate of the inert gas ejected from the first ejection port 616 is a small first flow rate (for example, 3 liters / minute).

[0077] In the substrate processing device 1, the inactive gas ejected from the first ejection port 616 forms a radial airflow from the central portion of the liquid film 93 of the processing liquid toward the periphery (that is, toward the radial outer side). Moreover, the holes 96 of the liquid film 93 of the processing liquid are enlarged by the airflow. As the holes 96 are enlarged, the processing liquid constituting the liquid film 93 moves toward the radial outer side, and the processing liquid on the peripheral portion of the substrate 9 flows down from the outer edge of the substrate 9 and is removed from the substrate 9. Therefore, the first nozzle 61 is a liquid removal portion for removing the liquid film 93 from the substrate 9.

[0078] In the substrate processing apparatus 1, in parallel with the inert gas being ejected from the first ejection port 616, the heating plate 51 of the heating unit 5 also continues to heat the substrate 9. As a result, the temperature of the substrate 9 in the region overlapping with the hole 96 of the liquid film 93 rises rapidly, and a temperature gradient is generated in the substrate 9. Since the liquid film 93 on the gas phase layer 94 moves from the high temperature side to the low temperature side (i.e., toward the radial outer side), the hole 96 of the liquid film 93 is also enlarged by the temperature gradient. As described above, since the processing liquid on the peripheral portion of the substrate 9 is removed from the substrate 9 as the hole 96 is enlarged, the heating unit 5 is also included in the liquid removal unit described above.

[0079] As described above, since the downflow of the clean gas begins to form again around the substrate 9, the liquid film 93 supported on the gas phase layer 94 in the peripheral portion of the substrate 9 is also moved radially outward by the downflow. In other words, the downflow promotes the processing liquid in the peripheral portion of the upper surface 91 of the substrate 9 to move radially outward (that is, to the outer edge of the substrate 9). As a result, the removal of the processing liquid on the peripheral portion of the substrate 9 is promoted.

[0080] In addition, in the substrate processing apparatus 1, in parallel with step S31 or after step S31, the cup 41 is moved downward by the cup moving mechanism 42, and as shown in FIG. Fig.11 As shown, the inner periphery of the cup top cover portion 44 of the cup 41 and the base portion 21 of the substrate holding portion 2 are arranged at the same position in the up-down direction. In other words, the inner periphery of the cup top cover portion 44 is located between the upper surface and the lower surface of the base portion 21 in the up-down direction. As a result, the gap between the base portion 21 and the cup 41 is reduced, and the flow path area of ​​the descending airflow flowing from the top of the cup 41 to the inside of the cup 41 around the base portion 21 becomes smaller (step S32). As a result, the flow rate of the descending airflow around the substrate 9 increases, further promoting the removal of the processing liquid on the peripheral portion of the substrate 9. In addition, step S32 can also be performed before step S31 as long as the rotation of the substrate 9 is stopped in step S14.

[0081] When starting from Fig.10 After a predetermined time has passed since the first nozzle 616 of the first nozzle 61 ejected the inert gas, the flow rate of the inert gas ejected from the first nozzle 616 is increased to a second flow rate (e.g., 30 liters / minute) that is larger than the first flow rate. This promotes the expansion of the pores 96 of the liquid film 93. In addition, the heating plate 51 is lowered to the standby position by the plate lifting mechanism 53, and the heating plate 51 stops heating the substrate 9.

[0082] like Fig.12 As shown, when the holes 96 of the liquid film 93 of the processing liquid become larger to a certain extent, in addition to the inert gas being ejected from the first nozzle 616 of the first nozzle 61, the inert gas is also ejected from the plurality of second nozzles 617 (step S33). The inert gas from the plurality of second nozzles 617 is ejected radially in a direction from the central portion of the liquid film 93 (that is, the central portion of the substrate 9) toward the surroundings. As a result, the holes 96 of the liquid film 93 of the processing liquid are further enlarged, and the processing liquid on the upper surface 91 of the substrate 9 flows down from the outer edge of the substrate 9 and is removed from the substrate 9. In addition, since the processing liquid on the peripheral portion of the substrate 9 can be efficiently moved radially outward by the radial gas flow from the plurality of second nozzles 617, it is possible to appropriately prevent or suppress the processing liquid from remaining on the peripheral portion of the substrate 9.

[0083] In addition, in the removal of the liquid film 93 of the processing liquid, step S33 (i.e., ejecting the inert gas from the plurality of second ejection ports 617) may be omitted. Even in this case, the liquid film 93 of the processing liquid on the upper surface 91 of the substrate 9 is moved from the central portion of the substrate 9 toward the outer edge and removed from the substrate 9 through steps S31 to S32.

[0084] When the removal of the liquid film 93 of the processing liquid is completed (step S20), the drying process of the substrate 9 is performed (step S21). In step S21, the substrate holding part 31 is rotated at a relatively high rotation speed in a state where the cup 41 is raised and positioned around the substrate 9. As a result, the liquid components that may remain on the substrate 9 are thrown off and removed, so that the substrate 9 is dried. In step S21, the inert gas is continuously sprayed from the first nozzle 61. Therefore, the droplets and mist splashed from the cup 41 are prevented or suppressed from adhering to the upper surface 91 of the substrate 9 again.

[0085] The substrate 9 after the drying process is carried out from the substrate processing apparatus 1. In the substrate processing apparatus 1, the processes of step S11 to step S21 are sequentially performed on a plurality of substrates 9.

[0086] As described above, the substrate processing apparatus 1 includes a substrate holding portion 2, a processing liquid supply portion, a heating portion 5, and a liquid removal portion. The substrate holding portion 2 holds the substrate 9 in a horizontal state. The processing liquid supply portion (the first nozzle 61 in the above example) supplies a processing liquid having a surface tension higher than that of IPA to the upper surface 91 of the substrate 9, thereby forming a liquid film 93 of the processing liquid covering the entire upper surface 91 of the substrate 9. The heating portion 5 heats the substrate 9 from the lower surface 92 side and vaporizes a portion of the liquid film 93, thereby forming a gas phase layer 94 between the upper surface 91 of the substrate 9 and the liquid film 93. The liquid removal portion (the first nozzle 61 in the above example) removes the liquid film 93 on the gas phase layer 94.

[0087] In this way, the liquid film 93 is formed by a processing liquid having a higher surface tension than IPA, compared with the case where the liquid film is formed by IPA, thereby preventing unexpected damage to the liquid film 93 before the liquid film 93 is removed (for example, the processing liquid flows down from the periphery of the substrate 9 and the chuck pins 23, or the liquid film 93 is cracked due to the vapor of the processing liquid generated between the liquid film 93 and the substrate 9). As a result, the heating time required to form the gas phase layer 94 of the processing liquid can be ensured, so that the liquid film 93 can be appropriately floated above the substrate 9. Therefore, the collapse of the pattern on the substrate 9 (that is, the collapse of the structure 911 described above) can be prevented or suppressed, and the liquid film 93 can be stably removed from the substrate 9.

[0088] As described above, it is preferred that the vapor pressure of the treatment liquid is higher than the vapor pressure of IPA. Thus, the gas phase layer 94 of the treatment liquid can be formed at a lower temperature than when the gas phase layer is formed by a liquid film of IPA. In addition, compared with the case where the gas phase layer is formed by a liquid film of IPA, the time required to form the gas phase layer 94 of the treatment liquid can be shortened as long as the heating temperature is the same as when the gas phase layer is formed by a liquid film of IPA. As a result, the liquid film 93 can be floated above the substrate 9 in a shorter time. In addition, the time required for processing the substrate 9 in the substrate processing device 1 can also be shortened.

[0089] Preferably, the treatment liquid includes cis-1,2-dichloroethylene (molecular formula: C2H2Cl2), chloroform (molecular formula: CHCl3), methyl acetate (molecular formula: C3H6O2), 1,3-dioxolane (molecular formula: C3H6O2), tetrahydrofuran (molecular formula: C4H8O), 1,1,1-trichloroethane (molecular formula: C2H3Cl3), tetrachloromethane (molecular formula: CCl4), benzene (molecular formula: C6H6), cyclohexane (molecular formula: C6H 12 ), acetonitrile (molecular formula: C2H3N), trichloroethylene (molecular formula: C2HCl3), tetrahydropyran (molecular formula: C5H 10 O), nitric acid (molecular formula: HNO3), 1,2-dichloroethane (molecular formula: C2H4Cl2), 1,2-dichloropropane (molecular formula: C3H6Cl2), fluorotrinitromethane (molecular formula: CFN3O6), pyrrolidine (molecular formula: C4H9N), acrylonitrile (molecular formula: C3H3N), cyclohexene (molecular formula: C6H 10 ) In this way, the surface tension and vapor pressure of the processing liquid can be set to be higher than the surface tension and vapor pressure of IPA.

[0090] As described above, it is preferred that the heating of the substrate 9 by the heating unit 5 (step S17) is started after the entire upper surface 91 of the substrate 9 is covered by the processing liquid supplied from the processing liquid supply unit (step S14). Thus, compared with the case where the substrate is heated before the processing liquid is supplied and the case where the substrate is heated before the processing liquid covers the entire upper surface of the substrate, it is possible to suppress a rapid increase in the temperature of the processing liquid supplied to the substrate 9 and a rapid vaporization. As a result, a liquid film 93 of the processing liquid can be stably and appropriately formed on the substrate 9.

[0091] In the substrate processing apparatus 1, the liquid removal unit preferably includes a gas ejection unit (in the above example, the first nozzle 61) for ejecting gas toward the center of the liquid film 93. In this case, the gas from the gas ejection unit forms a radial gas flow from the center of the liquid film 93 toward the periphery, so that the processing liquid moves from the center of the liquid film 93 toward the outer edge of the substrate 9 and is removed from the substrate 9. Thus, the liquid film 93 can be removed from the substrate 9 with a simple structure.

[0092] Preferably, the gas ejection portion includes a first ejection port 616 and a plurality of second ejection ports 617. The first ejection port 616 ejects gas toward the central portion of the liquid film 93. The plurality of second ejection ports 617 are circumferentially arranged around the first ejection port 616. The plurality of second ejection ports 617 eject gas radially from the central portion of the liquid film 93 toward the surroundings. Thus, the hole 96 formed in the central portion of the liquid film 93 can be rapidly enlarged. As a result, the liquid film 93 can be easily and rapidly removed from the substrate 9. In addition, compared with the case where a circumferential slit-shaped ejection port is provided, by circumferentially providing a plurality of smaller second ejection ports 617, the flow rate of the gas ejected from the second ejection ports 617 can be increased. As a result, it is possible to appropriately prevent or suppress the residual processing liquid in the peripheral portion of the substrate 9.

[0093] Preferably, the substrate processing device 1 further includes a chamber 11 and an airflow forming unit 71. The chamber 11 accommodates the substrate holding unit 2 in an internal space. The airflow forming unit 71 delivers gas from the upper part of the chamber 11 to the internal space, and forms a downward airflow from the upper side of the substrate 9 to the lower side around the substrate 9. When removing the processing liquid from the substrate 9, the downward airflow promotes the processing liquid in the peripheral portion of the upper surface 91 of the substrate 9 to move toward the outer edge. As a result, the liquid film 93 can be quickly removed from the substrate 9.

[0094] More preferably, the substrate processing device 1 further includes a rotating mechanism 3, a cup 41, and a cup moving mechanism 42. The rotating mechanism 3 rotates the substrate holding portion 2. The cup 41 is arranged around the substrate holding portion 2 with a gap therebetween. The cup 41 catches the liquid flying from the rotating substrate 9. The cup moving mechanism 42 moves the cup 41 relative to the substrate holding portion 2. When removing the processing liquid from the substrate 9, the cup 41 is relatively moved by the cup moving mechanism 42, thereby reducing the gap between the substrate holding portion 2 and the cup 41. As a result, the flow rate of the descending airflow described above around the substrate 9 can be increased. As a result, the liquid film 93 can be removed from the substrate 9 more quickly.

[0095] As described above, it is preferred that the airflow forming unit 71 stops forming the downflow when the heating unit 5 starts heating the substrate 9 (step S17). As a result, the peripheral portion of the liquid film 93 can be prevented from being cooled by the downflow. For example, the temperature of the peripheral portion of the substrate 9 that has been heated for a predetermined time after the downflow is stopped is about 10°C to 20°C higher than that of the case where the downflow is not stopped. As a result, the entire liquid film 93 can be heated approximately evenly and the gas phase layer 94 can be appropriately formed. In addition, the time required to heat the substrate 9 to a desired temperature can be shortened.

[0096] More preferably, before the heating unit 5 starts heating the substrate 9 (step S17), the processing liquid supply unit stops supplying the processing liquid (step S15), and at the same time, the airflow forming unit 71 stops forming the descending airflow (step S16). Thus, the peripheral edge of the processing liquid film 93 formed on the substrate 9 can be prevented from being disturbed by the descending airflow, so that the liquid film 93 can be stably maintained.

[0097] Furthermore, it is more preferable that the gas flow forming unit 71 starts to form the downflow again after the temperature of the peripheral portion of the substrate 9 becomes higher than the predetermined temperature (step S19). Thus, it is possible to prevent or suppress the temperature of the processing liquid from being lowered by the downflow during the formation of the gas phase layer 94 at the peripheral portion of the substrate 9, thereby hindering the formation of the gas phase layer 94.

[0098] The above-mentioned substrate processing method comprises the following steps: holding the substrate 9 in a horizontal state (step S11); supplying a processing liquid having a surface tension higher than that of IPA to the upper surface 91 of the substrate 9, thereby forming a liquid film 93 of the processing liquid covering the entire upper surface 91 of the substrate 9 (step S14); heating the substrate 9 from the lower surface 92 side and vaporizing a part of the liquid film 93, thereby forming a gas phase layer 94 between the upper surface 91 of the substrate 9 and the liquid film 93 (step S18); and removing the liquid film 93 on the gas phase layer 94 (step S20). Thus, as described above, compared with the case where the liquid film is formed by IPA, unexpected damage to the liquid film 93 before the liquid film 93 is removed can be suppressed. As a result, the heating time required to form the gas phase layer 94 of the processing liquid can be ensured, and the liquid film 93 can be appropriately floated above the substrate 9. Therefore, the collapse of the pattern on the substrate 9 can be prevented or suppressed, and the liquid film 93 can be stably removed from the substrate 9.

[0099] In the substrate processing device 1, in the case where the rinsing liquid and the processing liquid are not easy to get close to each other as described above, the IPA supply process can also be performed on the substrate 9 between the rinsing process (step S13) and the supply of the processing liquid to the substrate 9 (step S14). Specifically, after the rinsing process of the substrate 9 is completed, IPA is supplied to the rotating substrate 9 and spread to the entire upper surface 91 of the substrate 9. In this way, the rinsing liquid on the upper surface 91 of the substrate 9 is washed away and replaced with IPA. Thereafter, the supply of IPA to the substrate 9 is stopped, and the processing liquid is supplied to the rotating substrate 9 as described above. Next, the processing liquid spreads from the central part of the substrate 9 to the entire upper surface 91, and the IPA on the upper surface 91 of the substrate 9 is washed away and replaced with the processing liquid.

[0100] Thus, in the substrate processing apparatus 1, the processing liquid can be supplied from the processing liquid supply unit (the first nozzle 61 in the above example) to the upper surface 91 of the substrate 9 in a state where the entire upper surface 91 of the substrate 9 is covered with IPA. Then, the IPA on the upper surface 91 of the substrate 9 is replaced by the processing liquid, thereby forming a liquid film 93 of the processing liquid. Since the processing liquid and the IPA are relatively close, the processing liquid can be brought close to the substrate 9 and easily enter between the structures 911 of the pattern. As a result, the liquid film 93 of the processing liquid can be appropriately formed on the substrate 9.

[0101] The above-mentioned treatment liquid may also be a mixed liquid formed by mixing a substance having a higher surface tension than IPA and a lower vapor pressure than IPA into IPA. In this case, as described above, unexpected damage to the liquid film 93 before removing the liquid film 93 can be suppressed compared to the case where the liquid film is formed by IPA. In addition, since IPA and the rinsing liquid are relatively close, the replacement of the rinsing liquid and the treatment liquid in step S14 can be easily performed, or the replacement of IPA and the treatment liquid can be easily performed when IPA is supplied as described above. Furthermore, since the vapor pressure of the substance is lower than that of IPA, it is possible to prevent the surface tension of the treatment liquid from being reduced due to the fact that only the substance vaporizes earlier than IPA when the liquid film 93 of the treatment liquid is heated and the gas phase layer 94 is formed. As the substance, for example, allyl alcohol (molecular formula C3H6O) or 1-propanol (molecular formula C3H8O) can be used.

[0102] The above-described substrate processing apparatus 1 and substrate processing method may be modified in various ways.

[0103] For example, a circumferential slit-shaped ejection port may be provided in place of the plurality of second ejection ports 617, or a circumferential slit-shaped ejection port may be provided in addition to the plurality of second ejection ports 617, and the circumferential slit-shaped ejection port may eject gas radially from the central portion toward the periphery. In addition, an ejection port for ejecting gas may not be provided on the outer side surface of the first nozzle 61.

[0104] The processing liquid supplied to the substrate 9 in step S14 is not limited to the liquid described and exemplified above, and various liquids having a surface tension higher than IPA may be used as the processing liquid. For example, a liquid having a surface tension higher than IPA and a vapor pressure lower than IPA may be used as the processing liquid.

[0105] The stopping of the formation of the downflow in step S16 does not necessarily need to be performed simultaneously with the stopping of the supply of the processing liquid in step S15, and may be performed before or after step S15. In addition, the restarting of the formation of the downflow in step S19 may be performed regardless of the temperature of the peripheral portion of the substrate 9. In addition, the formation of the downflow may be continued without stopping the formation of the downflow during the period from step S11 to step S21.

[0106] As described above, when the heating unit 5 starts to heat the substrate 9, the airflow forming unit 71 stops forming the descending airflow, thereby heating the entire liquid film 93 substantially evenly and appropriately forming the gas phase layer 94. Therefore, from the perspective of substantially evenly heating the entire liquid film 93 of the processing liquid and appropriately forming the gas phase layer 94, the processing liquid does not necessarily need to be a liquid having a surface tension higher than IPA, and may be a liquid having a surface tension lower than IPA. For example, the processing liquid may also be IPA.

[0107] The heating of the substrate 9 in step S17 does not necessarily need to be started after the formation of the liquid film 93 in step S14, and may be started simultaneously with step S14 or before step S14. In addition, the heating unit 5 for heating the substrate 9 may also include a heating lamp, for example, instead of the heating plate 51, and the heating lamp is used to irradiate light to the lower surface 92 of the substrate 9 and heat the substrate 9.

[0108] In the removal of the liquid film 93 in step S20, since it is not necessary to reduce the gap between the substrate holding part 2 and the cup 41, step S32 may be omitted. In step S20, the downward airflow may not be used to promote the movement of the processing liquid.

[0109] In step S20, the removal of the liquid film 93 may be promoted by rotating the substrate 9. In this case, the liquid removal unit may include a rotating mechanism 3 for rotating the substrate 9.

[0110] The liquid removal unit may remove the liquid film 93 by various other methods. For example, a suction nozzle may be used as the liquid removal unit; the suction nozzle is inserted into the liquid film 93 supported on the gas phase layer 94 and sucks the liquid film 93, thereby removing the liquid film 93 from the substrate 9. Alternatively, a sponge or the like may be used as the liquid removal unit, and the sponge contacts the upper surface of the liquid film 93 supported on the gas phase layer 94 and absorbs the liquid film 93. In addition, the liquid film 93 may be removed from the substrate 9 by ejecting an inert gas in a strip shape from a slit-shaped inert gas outlet longer than the diameter of the substrate 9 toward the upper surface 91 of the substrate 9 while reciprocating the inert gas outlet above the substrate 9.

[0111] In addition to being used for processing semiconductor substrates, the substrate processing device 1 can also be used for processing glass substrates used in flat panel displays such as liquid crystal display devices or organic EL (Electro Luminescence) display devices, or can also be used for processing glass substrates used in other display devices. In addition, the substrate processing device 1 can also be used for processing optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, photomask substrates, ceramic substrates, and solar cell substrates.

[0112] The configurations in the above-described embodiment and various modifications may be appropriately combined unless they are contradictory to each other.

[0113] Although the present invention has been described and illustrated in detail, the above description is illustrative only and not restrictive. Therefore, many changes and modifications are possible without departing from the scope of the present invention.

[0114] [Description of Reference Numerals]

[0115] 1Substrate processing device

[0116] 2 substrate holding part

[0117] 3 Rotating mechanism

[0118] 5. Heating unit

[0119] 9 substrates

[0120] 11 Chambers

[0121] 41 cups

[0122] 42 cups mobile mechanism

[0123] 61 First Nozzle

[0124] 71 air flow forming part

[0125] 91 upper surface (of substrate)

[0126] 92 (substrate) lower surface

[0127] 93 Liquid Film

[0128] 94 Gas Phase

[0129] 616 First outlet

[0130] 617 Second Exit

[0131] Steps S11 to S21, S31 to S33

Claims

1. A substrate processing device for processing a substrate, comprising: A substrate holding portion, which holds the substrate in a horizontal state; a processing liquid supplying unit for supplying a processing liquid having a surface tension higher than that of isopropyl alcohol to the upper surface of the substrate, thereby forming a liquid film of the processing liquid covering the entire upper surface of the substrate; a heating unit that heats the substrate from a lower surface side and vaporizes a portion of the liquid film, thereby forming a gas phase layer between the upper surface of the substrate and the liquid film; as well as a liquid removal unit for removing the liquid film on the gas phase layer; In a state where the entire upper surface of the substrate is covered with isopropyl alcohol, the processing liquid is supplied from the processing liquid supply unit to the upper surface of the substrate, and the isopropyl alcohol on the upper surface of the substrate is replaced by the processing liquid, thereby forming the liquid film of the processing liquid.

2. The substrate processing apparatus according to claim 1, wherein: The liquid removal unit includes: a gas ejection unit that ejects gas toward a central portion of the liquid film; The gas from the gas ejection portion forms a radial gas flow from the center of the liquid film toward the periphery, so that the processing liquid moves from the center of the liquid film toward the outer edge of the substrate and is removed from the substrate.

3. The substrate processing apparatus according to claim 2, wherein: The gas ejection unit comprises: a first ejection port ejecting gas toward the central portion of the liquid film; and The plurality of second ejection ports are circumferentially arranged around the first ejection port, and eject gas radially in a direction from the center portion of the liquid film toward the periphery.

4. The substrate processing apparatus according to claim 2, wherein: Further possesses: a chamber, accommodating the substrate holding portion in an internal space; and an air flow forming unit for delivering gas from an upper portion of the chamber to the inner space and forming a downward air flow from an upper side to a lower side of the substrate around the substrate; The downdraft promotes movement of the processing liquid in the peripheral portion of the upper surface of the substrate toward the outer edge when removing the processing liquid from the substrate.

5. The substrate processing apparatus according to claim 4, wherein: Further possesses: A rotating mechanism for rotating the substrate holding portion; a cup, arranged around the substrate holding portion with a gap therebetween, for catching liquid scattered from the rotating substrate; as well as a cup moving mechanism for relatively moving the cup relative to the substrate holding portion; When removing the processing liquid from the substrate, the cup is relatively moved by the cup moving mechanism to reduce the gap between the substrate holding portion and the cup.

6. A processing liquid used in processing a substrate, wherein: The processing liquid has a surface tension higher than that of isopropyl alcohol, and the processing liquid is supplied to the upper surface of the substrate in the substrate processing apparatus according to any one of claims 1 to 5.

7. A substrate processing method for processing a substrate, comprising: Step (a), keeping the substrate in a horizontal state; Step (b), supplying a treatment liquid having a surface tension higher than that of isopropyl alcohol to the upper surface of the substrate, thereby forming a liquid film of the treatment liquid covering the entire upper surface of the substrate; Step (c), heating the substrate from the lower surface side and vaporizing a portion of the liquid film, thereby forming a gas phase layer between the upper surface of the substrate and the liquid film; as well as Step (d), removing the liquid film on the gas phase layer, In the step (b), the processing liquid is supplied to the upper surface of the substrate while the entire upper surface of the substrate is covered with isopropyl alcohol, and the isopropyl alcohol on the upper surface of the substrate is replaced by the processing liquid, thereby forming the liquid film of the processing liquid.

Images