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

Abstract

The present invention provides a substrate drying apparatus, a substrate processing apparatus, and a substrate drying method. The substrate drying apparatus according to an embodiment includes: a heating unit; a first volatile solvent supply unit; a second volatile solvent supply unit that supplies a second volatile solvent, the second volatile solvent containing a water repellent agent and having a surface tension smaller than that of the first volatile solvent when vaporized; a drying chamber into which a substrate having a liquid film formed thereon is carried; a driving mechanism that rotates the substrate; and a control device that supplies the first volatile solvent from the first volatile solvent supply unit to replace the liquid film with the first volatile solvent, supplies the second volatile solvent from the second volatile solvent supply unit to replace the first volatile solvent formed on the substrate with the second volatile solvent, and forms a water repellent film, causes the heating unit to heat the substrate, generates an air layer between the liquid film of the second volatile solvent and the substrate, and discharges the liquid film of the second volatile solvent by the centrifugal force generated by the rotation.

Description

Technical Field

[0001] The present invention relates to a substrate drying apparatus, a substrate processing apparatus, and a substrate drying method. Background Art

[0002] In manufacturing processes for semiconductors, liquid crystal panels, etc., the following substrate processing apparatus is used: a processing liquid is supplied to a surface to be processed of a substrate such as a wafer or a liquid crystal substrate to process the surface to be processed, and after the processing, the surface to be processed is washed and dried.

[0003] In the drying process of the substrate processing apparatus, there are cases where patterns such as memory cells and around gates collapse and block due to the interval between patterns, structure, surface tension of the processing liquid, etc. In particular, with the miniaturization accompanying the high integration and high capacity of semiconductors in recent years, the aspect ratio, which is the ratio of depth to wiring width or opening width, becomes high, so pattern collapse is likely to occur.

[0004] To suppress such pattern collapse, a substrate drying method has been proposed in which after rinsing with deionized water (DIW) (ultrapure water), isopropyl alcohol (IPA) (2-propanol: isopropyl alcohol) is used. In this substrate drying method, the DIW (ultrapure water) on the substrate surface is replaced with IPA having a smaller surface tension than DIW to reduce pattern collapse caused by surface tension during the drying process.

[0005] [Prior Art Documents]

[0006] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Laid-Open No. 2008-034779 Summary of the Invention

[0008] [Problems to be Solved by the Invention]

[0009] However, the miniaturization of semiconductors is progressing, and even in the case of drying using an organic solvent (volatile solvent) with high volatility such as IPA, sometimes the fine patterns of the wafer collapse due to the surface tension of the liquid, etc.

[0010] For example, when the drying speed on the substrate surface is uneven during the liquid drying process and liquid remains between some patterns, the surface tension of this part of the liquid causes pattern collapse. Specifically, the patterns in the part where the liquid remains collapse due to elastic deformation caused by the surface tension of the liquid, and some residues dissolved in the liquid accumulate. Subsequently, when the liquid is completely vaporized, the collapsed patterns are fixed and blocked.

[0011] In order to address the above problems, in addition to supplying IPA, a water-repellent agent, which is a modifier capable of making the surface of the substrate W water-repellent, is supplied. Thus, the hydroxyl groups on the substrate surface are replaced with functional groups by the water-repellent agent that penetrates into the liquid film of IPA, thereby forming a water-repellent film. As a result, a water-repellent film is also formed between the patterns, the lyophilicity is reduced, and the liquid contact angle increases. That is, the surface tension of the liquid located on the substrate surface becomes further lower, so that the force attracting the patterns to each other can be weakened, and thus pattern collapse can be suppressed.

[0012] When using a water-repellent agent, after forming a water-repellent film by supplying the water-repellent agent, rinsing treatment is performed using IPA or the like to remove the excess water-repellent agent, and then drying treatment is performed. However, after the drying treatment, the water-repellent film formed on the substrate surface also remains. Therefore, a water-repellent film removal treatment for removing the water-repellent film on the substrate surface is required. The removal of the water-repellent film is performed, for example, by plasma treatment for ashing or ultraviolet (UV) irradiation treatment.

[0013] Therefore, it is necessary to add a removal device such as a plasma treatment device or a UV irradiation device independent of the drying device to the substrate processing device, and a transfer process from the drying device to the removal device is required. As a result, the substrate processing device becomes complicated and large-sized, the number of processes increases, and the productivity of substrate processing decreases. Furthermore, if the pattern becomes deeper and the aspect ratio increases, it may not be possible to remove the water-repellent film to the bottom of the pattern by UV irradiation.

[0014] An object of an embodiment of the present invention is to provide a substrate drying device, a substrate processing device, and a substrate drying method that can reduce the occurrence of pattern clogging with a simple structure.

[0015] [Technical means for solving the problem]

[0016] The substrate drying apparatus according to an embodiment of the present invention includes: a heating unit that heats a substrate; a first volatile solvent supply unit that supplies a first volatile solvent to a surface to be processed of the substrate; a second volatile solvent supply unit that supplies a second volatile solvent to the surface to be processed of the substrate, the second volatile solvent including a water-repellent agent for forming a water-repellent film and having a smaller surface tension than the first volatile solvent when vaporized; a drying chamber that houses the heating unit, the first volatile solvent supply unit, and the second volatile solvent supply unit, and into which the substrate in a state where a liquid film formed of a processing liquid is formed on the surface to be processed is carried; a support unit that receives the substrate carried into the drying chamber; a driving mechanism that rotates the substrate supported by the support unit; and a control device that replaces the liquid film formed of the processing liquid on the surface to be processed of the substrate with the first volatile solvent by supplying the first volatile solvent from the first volatile solvent supply unit, replaces the first volatile solvent on the surface to be processed of the substrate with the second volatile solvent by supplying the second volatile solvent from the second volatile solvent supply unit, and forms the water-repellent film on the surface to be processed of the substrate, and generates an air layer between the liquid film of the second volatile solvent including the water-repellent agent and the substrate by heating the substrate with the heating unit, thereby discharging the liquid film of the second volatile solvent by centrifugal force caused by the rotation of the substrate.

[0017] The substrate processing apparatus according to an embodiment of the present invention includes: a processing device that performs processing by supplying a first processing liquid while rotating the substrate; a cleaning device that performs cleaning by supplying a second processing liquid while rotating the substrate processed by the processing device; the substrate drying apparatus; and a transfer device that carries out and carries into the substrate drying apparatus the substrate cleaned by the cleaning device in a state where a liquid film formed of the second processing liquid supplied by the cleaning device is formed.

[0018] In the substrate drying method according to an embodiment of the present invention, while a substrate having a liquid film formed of a processing liquid and supported by a support portion is rotated by a driving mechanism, the liquid film formed of the processing liquid is replaced with the first volatile solvent by supplying the first volatile solvent from a first volatile solvent supply portion, and the liquid film of the first volatile solvent is replaced with a second volatile solvent by supplying a second volatile solvent containing a water-repellent agent for forming a water-repellent film and having a surface tension smaller than that of the first volatile solvent when vaporized from a second volatile solvent supply portion, and a water-repellent film is formed on the substrate. By heating the substrate using a heating portion, an air layer is generated between the liquid film of the second volatile solvent containing the water-repellent agent and the substrate, and thus the liquid film of the second volatile solvent is discharged by the centrifugal force brought about by the rotation of the substrate.

[0019] [Effects of the Invention]

[0020] An embodiment of the present invention can provide a substrate drying apparatus, a substrate processing apparatus, and a substrate drying method that reduce the occurrence of pattern occlusion with a simple structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic structural diagram of a substrate processing apparatus according to an embodiment.

[0022] Figure 2 It represents Figure 1 The structural diagram of the cleaning device and the drying device of the substrate processing apparatus.

[0023] Figure 3 Of (A) and Figure 3 Of (B) is an internal structural diagram showing the substrate loading (A) and the first volatile solvent supply (B) during the drying process.

[0024] Figure 4 Of (A) and Figure 4 Of (B) is an internal structural diagram showing the second water-repellent solvent supply (A), the first volatile solvent supply, and the film thickness measurement (B) during the drying process.

[0025] Figure 5 It is an internal structural diagram showing the substrate drying process.

[0026] Figure 6 It is a flowchart showing the next step of the substrate drying process according to an embodiment.

[0027] Figure 7 Of (A) to Figure 7 Of (E) is an explanatory diagram schematically showing the process of the drying process utilizing the Leidenfrost phenomenon.

[0028] Figure 8 Explanation diagram showing the liquid film remaining in the pattern.

[0029] [Explanation of symbols]

[0030] 1: Substrate processing apparatus

[0031] 1a: Chamber

[0032] 1b: Cassette

[0033] 1c: Transfer robot

[0034] 1d: Buffer unit

[0035] 11: Cleaning chamber

[0036] 11a: Opening

[0037] 11b: Door

[0038] 12: Support part

[0039] 13: Rotation mechanism

[0040] 14: Shield

[0041] 15: Supply part

[0042] 15a: Nozzle

[0043] 15b: Moving mechanism

[0044] 20: Transfer device

[0045] 21: Manipulator

[0046] 22: Moving mechanism

[0047] 31: Drying chamber

[0048] 31a: Opening

[0049] 31b: Door

[0050] 31c: Inlet

[0051] 31d: Exhaust port

[0052] 31e: Gas supply part

[0053] 31f: Exhaust part

[0054] 32: Support part

[0055] 32a: Rotating table

[0056] 32b: Holding member

[0057] 32c: Rotation axis

[0058] 33: Driving mechanism

[0059] 33a: Rotating part

[0060] 33b: Lifting part

[0061] 34: First volatile solvent supply unit

[0062] 34a: Nozzle

[0063] 34b: Swing arm

[0064] 34c: Swing mechanism

[0065] 35: Second volatile solvent supply unit

[0066] 35a: Nozzle

[0067] 35b: Swing arm

[0068] 35c: Swing mechanism

[0069] 36: Heating part

[0070] 36a: Lamp

[0071] 36b: Window part

[0072] 37: Shield

[0073] 38: Measuring part

[0074] 38a: Detection part

[0075] 38b: Swing arm

[0076] 38c: Swing mechanism

[0077] 41: Mechanism control part

[0078] 42: Film thickness analysis part

[0079] 43: Heating control part

[0080] 110: Processing device

[0081] 120: Cleaning device

[0082] 200: Conveying device

[0083] 300: Drying device (substrate drying device)

[0084] 400: Control device

[0085] F: Liquid film

[0086] G: Gas layer

[0087] H: Second volatile solvent

[0088] L: Cleaning liquid

[0089] P: Pattern

[0090] R: Water-repellent film

[0091] W: Substrate

[0092] V: First volatile solvent

[0093] S01, S02, S03, S04, S05, S06, S07, S08, S09, S10, S11: Steps Detailed implementation mode

[0094] Hereinafter, with reference to the accompanying drawings, the implementation modes of the present invention will be described.

[0095] [Overview]

[0096] As Figure 1 shown, the substrate processing apparatus 1 of the present embodiment includes a plurality of chambers 1a that house devices for performing various processes, and is a single-sheet processing apparatus that processes each of a plurality of substrates W conveyed in a wafer cassette (Front Opening Unified Pod, FOUP) 1b in the previous process one by one in each chamber 1a. The unprocessed substrate W is taken out one by one from the wafer cassette 1b by a transfer robot 1c, temporarily placed on a buffer unit 1d, and then transferred to each chamber 1a and processed by various devices described below.

[0097] The substrate processing apparatus 1 includes a processing device 110, a cleaning device 120, a transfer device 200, a drying device 300, and a control device 400. The processing device 110 is, for example, a device that removes an unnecessary film by supplying a first processing liquid (such as an aqueous phosphoric acid solution, a mixed solution of hydrofluoric acid and nitric acid, acetic acid, a mixed solution of sulfuric acid and hydrogen peroxide water (Sulfuric acid Hydrogen Peroxide Mixture, SPM), etc.) to a rotating substrate W and leaves a circuit pattern. The cleaning device 120 cleans the substrate W that has been etched by the etching device using a cleaning liquid (second processing liquid). The transfer device 200 transfers the substrate W between the buffer unit 1d and each chamber 1a, and between each chamber 1a. For example, the transfer device 200 transfers the substrate W processed in the processing device 110 to the cleaning device 120, and transfers the substrate W cleaned in the cleaning device 120 to the drying device 300. The drying device (substrate drying device) 300 performs a drying process by heating while rotating the substrate W cleaned with the cleaning liquid. The control device 400 controls the above-described various devices.

[0098] In addition, the substrate W processed by this embodiment is, for example, a semiconductor wafer. Hereinafter, the surface of the substrate W on which a pattern or the like is formed is defined as the surface to be processed. As the processing liquid for the cleaning process, i.e., the cleaning liquid, an alkali cleaning liquid (Ammonia peroxide mixture, APM), ultrapure water (DIW), and a first volatile solvent (IPA) are used. APM is a liquid medicine obtained by mixing ammonia water and hydrogen peroxide water, and is used to remove residual organic substances. DIW is used to rinse the APM remaining on the surface to be processed of the substrate W after the APM treatment. Since the surface tension of IPA is smaller than that of DIW and its volatility is high, it is used to displace DIW and reduce pattern collapse caused by surface tension.

[0099] In addition, in this embodiment, a second volatile solvent is used. The second volatile solvent is a solvent whose surface tension during vaporization is smaller than that of the first volatile solvent. In addition, the temperature at which the second volatile solvent vaporizes is higher than that of the first volatile solvent. As such a second volatile solvent, propylene glycol monomethylether acetate (PGMEA) can be used. In addition, the second volatile solvent uses a solvent containing a water-repellent agent. The water-repellent agent is a modifier that can replace the hydroxyl group (-OH) on the surface to be processed of the substrate W with a functional group (e.g., -CH3, C2H5) to form a water-repellent film (Si-O-R (R: functional group)). For example, as the water-repellent agent, hexamethyldisilazane (HMDS), which is a silane coupling agent, can be used. In the following description, the supply of the second volatile solvent is performed in a form of supplying the second volatile solvent containing the water-repellent agent.

[0100] The reason for using a substance containing HMDS in PGMEA is that HMDS easily reacts with moisture. That is, if HMDS reacts with moisture in the air, the water-repellent effect on the substrate W will be lost. Therefore, by mixing HMDS in PGMEA, the reaction with moisture in the air can be prevented, and thus it can be supplied to the substrate W. In addition, the surface tension of PGMEA during vaporization is smaller than the surface tension of IPA during vaporization. For example, when the boiling point temperature of IPA is 82.5 °C (during vaporization), the value of the surface tension is 15.7 mN / m. On the other hand, when the boiling point of PGMEA is 145.8 °C (during vaporization), the value of the surface tension is 11.72 mN / m to 15.47 mN / m.

[0101] [Cleaning device]

[0102] As Figure 2As shown in the figure, the cleaning device 120 includes a cleaning chamber 11, a support portion 12, a rotation mechanism 13, a shield 14, and a supply portion 15. The cleaning chamber 11 is a container for performing cleaning processing inside. The support portion 12 supports the substrate W. The rotation mechanism 13 rotates the support portion 12. The shield 14 intercepts the scattered cleaning liquid L from around the substrate W. The supply portion 15 supplies the cleaning liquid L. The supply portion 15 is provided with a nozzle 15a for dropping the cleaning liquid L and a moving mechanism 15b for moving the nozzle 15a.

[0103] The cleaning liquid L is supplied from the nozzle 15a to the surface to be processed of the substrate W supported on the support portion 12 and rotated by the rotation mechanism 13, thereby performing the cleaning process. During the cleaning process, APM is supplied to the surface to be processed of the substrate W that has been etched by the processing device 110 for APM cleaning. After APM cleaning, pure water rinsing is performed using DIW. Thus, the APM remaining on the surface to be processed of the substrate W is rinsed with pure water. As a result, the surface to be processed of the substrate W is filled with the cleaning liquid L of DIW. The cleaning chamber 11 is provided with an opening 11a for loading and unloading the substrate W, and the opening 11a is configured to be opened and closed by a door 11b.

[0104] [Transfer device]

[0105] The transfer device 200 includes a transfer device 20. The transfer device 20 includes a robot 21 for gripping the substrate W and a moving mechanism 22. The robot 21 grips the substrate W. The moving mechanism 22 moves the robot 21. The transfer device 200 transfers the substrate W between the buffer unit 1d and various devices and between various devices. For example, the substrate W after the etching process is unloaded from the processing device 110 and transferred into the cleaning device 120 in a state where a liquid film of the cleaning liquid (DIW) L is formed on the surface to be processed of the substrate W. In addition, the moving mechanism 22 unloads the substrate W after cleaning from the cleaning device 120 and transfers it into the drying device 300 in a state where a liquid film of the cleaning liquid (DIW) L is formed on the surface to be processed of the substrate W. Furthermore, the reason for transferring in a state where a liquid film of the cleaning liquid (DIW) L is formed on the surface to be processed of the substrate W is to prevent particles from adhering to the surface to be processed of the substrate W during the transfer of the substrate W.

[0106] [Drying device]

[0107] As Figure 2As shown, the drying device 300 includes a drying chamber 31, a support portion 32, a drive mechanism 33, a first volatile solvent supply portion 34, a second volatile solvent supply portion 35, a heating portion 36, a shield 37, and a measurement portion 38. The drying chamber 31 is a chamber 1a for drying the substrate W inside. The drying chamber 31 has a box shape such as a rectangular parallelepiped or a cube, for example. To improve dust-proof performance, the inner wall of the drying chamber 31 is coated with silica. An opening 31a for loading or unloading the substrate W is provided in the drying chamber 31. The opening 31a is configured to be opened and closed by a door 31b. In such a drying chamber 31, the first volatile solvent supply portion 34, the second volatile solvent supply portion 35, and the heating portion 36 described below are accommodated.

[0108] In addition, an inlet 31c and an exhaust port 31d are provided in the drying chamber 31. A gas supply portion 31e including a pipe, an intake valve, and a gas supply device for supplying a clean gas (such as N2) is connected to the inlet 31c. An exhaust portion 31f including a pipe, an exhaust valve, and an exhaust device for exhausting the gas is connected to the exhaust port 31d. By supplying a clean gas into the drying chamber 31 from the inlet 31c, a normal atmosphere can be formed inside the drying chamber 31. In addition, by forming a structure in which gas is supplied into the drying chamber 31 from the inlet 31c and the gas inside the drying chamber 31 is discharged from the exhaust port 31d, a gas flow inside the drying chamber 31 is formed. As a result, the following structure is obtained: the vapor of the processing liquid generated when the substrate W is heated does not fill the inside of the drying chamber 31 and can be discharged from the drying chamber 31.

[0109] The support portion 32 supports the substrate W. The support portion 32 includes a turntable 32a, a plurality of holding members 32b, and a rotating shaft 32c. The turntable 32a has a cylindrical shape with a diameter larger than that of the substrate W, and its upper surface is a flat disk. The plurality of holding members 32b are arranged at equal intervals along the outer periphery of the substrate W, and the substrate W is held in a horizontal state with a space between the upper surface of the turntable 32a. The plurality of holding members 32b are configured to be movable between a closed position in contact with the edge of the substrate W and an open position away from the edge of the substrate W by an opening / closing mechanism (not shown). The rotating shaft 32c is a vertical shaft that supports the turntable 32a from below and serves as the center of rotation.

[0110] The drive mechanism 33 is a mechanism for rotating the substrate W supported by the support portion 32. The drive mechanism 33 includes a drive source such as a motor, and rotates the support portion 32 via the rotating shaft 32c.

[0111] The first volatile solvent supply unit 34 supplies the first volatile solvent V onto the substrate W that is carried into the drying chamber 31 and supported by the support unit 32. The first volatile solvent supply unit 34 includes a nozzle 34a, a swing arm 34b, and a swing mechanism 34c. The nozzle 34a supplies the first volatile solvent V near the center of the surface of the substrate W to be processed. IPA as the first volatile solvent V is supplied to the nozzle 34a from a storage unit outside the drying chamber 31 via a pipe (not shown) or the like.

[0112] In the cleaning process of the cleaning device 120, through the pure water rinsing process using DIW after the alkali cleaning using APM, the surface of the substrate W to be processed is finally filled with the cleaning liquid L of DIW. By supplying IPA to the substrate W carried from the cleaning device 120 to the drying device 300 in such a filled state, the DIW is replaced with IPA.

[0113] The swing arm 34b is provided with the nozzle 34a at its front end, and moves the nozzle 34a to a supply position facing near the center of the surface of the substrate W on the support unit 32 and a retracted position where the substrate W can be carried in or out by retracting from the supply position. The swing mechanism 34c is a mechanism that swings the swing arm 34b.

[0114] The second volatile solvent supply unit 35 supplies PGMEA (a solvent containing HMDS) as the second volatile solvent H to the IPA in which the DIW on the substrate W has been replaced (refer to Figure 4 of (A)). The second volatile solvent supply unit 35 includes a nozzle 35a, a swing arm 35b, and a swing mechanism 35c. The nozzle 35a supplies the second volatile solvent H near the center of the surface of the substrate W to be processed. PGMEA is supplied to the nozzle 35a from a storage unit outside the drying chamber 31 via a pipe (not shown) or the like.

[0115] By supplying the second volatile solvent H containing a water-repellent agent, a water-repellent film is formed on the surface of the substrate W to be processed. Therefore, the surface of the substrate W to be processed is changed from a hydrophilic silanol group to a water-repellent methyl group, reducing the interfacial energy on the surface of the substrate W to be processed, thereby floating the first volatile solvent V and promoting the removal of the liquid on the surface of the substrate W to be processed. In addition, the water repellency mentioned here refers to the property of repelling liquids, that is, liquid repellency, and is not limited to the property of repelling water.

[0116] The swing arm 35b is provided with the nozzle 35a at its front end, and moves the nozzle 35a to a supply position facing near the center of the surface of the substrate W on the support unit 32 and a retracted position where the substrate W can be carried in or out by retracting from the supply position. The swing mechanism 35c is a mechanism that swings the swing arm 35b.

[0117] The heating unit 36 is a device for heating the substrate W. The heating unit 36 is provided in the upper part of the drying chamber 31. The heating unit 36 has lamps 36a such as halogen lamps and infrared lamps. In addition, the lamp 36a is a lamp capable of irradiating ultraviolet light, visible light, and infrared light. The lamp 36a in the present embodiment is straight-tube-shaped, and a plurality of lamps 36a arranged in a horizontal state in parallel are arranged in a manner of overlapping into two layers, and the direction of the first-layer lamp 36a is orthogonal to that of the second-layer lamp 36a, so that it is formed in a lattice shape as a whole. Thus, it is configured to heat evenly.

[0118] In addition, the heating unit 36 uses electromagnetic waves (infrared rays) of a wavelength that can heat the substrate W itself more easily than the liquid itself on the surface to be processed of the substrate W, that is, the first volatile solvent V and the second volatile solvent H. Thus, the generation of an air layer due to the heat from the substrate W can be promoted. As the heating temperature, for example, it is preferably set to 300 °C or higher.

[0119] In addition, a window portion 36b is provided in the drying chamber 31. The window portion 36b is a member that allows electromagnetic waves from the heating unit 36 to pass through. As the window portion 36b, for example, a plate-like body such as quartz can be used. The window portion 36b is provided directly below the heating unit 36 in the drying chamber 31, separating the heating unit 36 from the support portion 32. Thus, it is possible to prevent fine particles generated from the expansion and contraction of the members of the connector portion of the lamp 36a due to the repeated lighting of the lamp 36a from adhering to the substrate W from above and causing metal contamination.

[0120] The hood 37 is formed in a cylindrical shape so as to surround the support portion 32 from the surroundings (refer to Figure 2 ). The upper part of the peripheral wall of the hood 37 is inclined toward the inner side in the radial direction and is opened so that the substrate W on the support portion 32 is exposed. The hood 37 catches the cleaning liquid L scattered from the rotating substrate W and flows downward. A discharge port (not shown) for discharging the flowing-down cleaning liquid L is formed on the bottom surface of the hood 37. In addition, the hood 37 is connected to the drive mechanism 33 and is provided so as to be able to move up and down together with the support portion 32.

[0121] The measuring unit 38 measures the film thickness of the liquid on the substrate W that is carried into the drying chamber 31 and supported by the support portion 32. The measuring unit 38 has a detection unit 38a, a swing arm 38b, and a swing mechanism 38c. As the detection unit 38a, for example, a laser displacement meter or a camera is used. The swing arm 38b is provided with the detection unit 38a at the front end, and moves the detection unit 38a to a measurement position and a standby position. The measurement position is a position where the detection unit 38a faces the center and the vicinity of the outer periphery of the surface to be processed of the substrate W on the support portion 32, and the standby position is a position where the detection unit 38a retreats so that the substrate W can be carried in or out. The swing mechanism 38c is a mechanism that swings the swing arm 38b.

[0122] As the film thickness measurement method adopted by the measurement unit 38, for example, the principle of optical interference can be used. In addition, as another example, a weighing scale can be used inside the support unit 32. In the case of using the weighing scale, the weight of the liquid film on the substrate W (weight of the liquid film = weight of the substrate including the liquid film - weight of the substrate) is converted into the thickness of the liquid film theoretically or experimentally.

[0123] [Control device]

[0124] The control device 400 is a computer that controls each part of the substrate processing device 1. The control device 400 has a processor, a memory, and a drive circuit. The processor executes programs, the memory stores various information such as programs or operation conditions, and the drive circuit drives each component. In addition, the control device 400 has an input device and a display device. The input device inputs information, and the display device displays information.

[0125] The control device 400 controls the processing device 110, the cleaning device 120, the transfer device 200, and the drying device 300. For example, while rotating the substrate W supported by the support unit 32, the control device 400 replaces the liquid film with the first volatile solvent V by supplying the first volatile solvent V from the first volatile solvent supply unit 34, and replaces the first volatile solvent V supplied to the surface to be processed of the substrate W with the second volatile solvent H by supplying the second volatile solvent H from the second volatile solvent supply unit 35. Then, after heating the substrate W by the heating unit 36, when the PGMEA as the second volatile solvent H is vaporized, the water-repellent film is detached from the surface to be processed of the substrate W. Thus, the liquid film of the second volatile solvent H is discharged by the centrifugal force generated by the rotation of the substrate W. For example, the boiling point of PGMEA is 140°C to 150°C, and the boiling point of HMDS as the water-repellent agent is about 300°C. Therefore, during the instantaneous temperature rise caused by heating, PGMEA is vaporized first, and then the chemical bond of the water-repellent film is thermally cut and removed. In addition, when the control device 400 determines that the film thickness as the measurement result obtained by the measurement unit 38 is within the range of a specified threshold, it starts heating by the heating unit 36.

[0126] Such a control device 400 has a mechanism control unit 41, a film thickness analysis unit 42, and a heating control unit 43. The mechanism control unit 41 controls the mechanisms of each part. For example, the mechanism control unit 41 controls the rotation speed of the support unit 32, the start and stop times of rotation by controlling the drive mechanism 33. In addition, it controls the actions such as the swing of the nozzle 34a and the ejection of the first volatile solvent V, the swing of the nozzle 35a and the ejection of the second volatile solvent H, and the swing and measurement of the detection unit 38a.

[0127] The film thickness analysis unit 42 analyzes the measurement results obtained by measuring the measurement unit 38, that is, the thickness of the liquid films of the first volatile solvent V and the second volatile solvent H measured by the measurement unit 38. The film thickness analysis unit 42 determines whether the thickness of the liquid film (liquid film thickness value) measured by the measurement unit 38 is within a specified threshold range. Then, when it is determined that the thickness of the measured liquid film is within the specified threshold range, the film thickness analysis unit 42 determines that the thickness of the liquid film is appropriate, and the heating control unit 43 sends a signal for commanding heating to the heating unit 36.

[0128] In addition, an appropriate film thickness when supplying PGMEA (second volatile solvent) containing HMDS (hydrophobic agent) is, for example, 100 μm or less. The film thickness is a liquid film thickness that can be dried well on the basis of delaying the evaporation from the substrate W caused by the heating of the heating unit 36 and performing a drying process based on the Leidenfrost phenomenon. However, these values are examples, and in practice, an appropriate liquid film thickness can be obtained in advance through experiments or the like. In addition, the rotation speed of the substrate W is, for example, about 200 rpm to 300 rpm. Even if the liquid film is adjusted, within this range of rotation speed, the liquid film thickness can be maintained at a specified thickness.

[0129] [Operation]

[0130] In addition to referring to the Figure 1 and Figure 2 in addition, also refer to Figure 3 (A) of Figure 3 and Figure 5 (B) to Figure 6 (E) of Figure 7 (A) of Figure 7 (E) of Figure 8 The operation of the substrate processing apparatus 1 of the present embodiment as described above is described with reference to the explanatory drawings of

[0131] First, as Figure 2 shown, the substrate W after the etching process in the processing apparatus 110 is carried into the cleaning apparatus 120 by the transfer apparatus 200. In the cleaning apparatus 120, while the support portion 12 holding the substrate W rotates, the supply portion 15 supplies APM to the rotation center of the surface to be processed of the substrate W and performs a rinsing process with an alkali, and then performs a pure water rinsing process by supplying DIW. The transfer apparatus 200 takes out the substrate W filled with the cleaning liquid L as DIW after cleaning from the cleaning apparatus 120 and carries it into the drying apparatus 300.

[0132] As Figure 3As shown in (A), in a state where a liquid film (DIW) of the cleaning liquid L is formed on the surface to be processed, the holding member 32b of the support portion 32 holds the substrate W carried in from the opening 31a of the drying chamber 31 of the drying apparatus 300 (step S01). As Figure 3 As shown in (B), while the driving mechanism 33 rotates the substrate W together with the support portion 32 (step S02), the first volatile solvent supply portion 34 supplies IPA as the first volatile solvent V to the rotation center of the surface to be processed of the substrate W (step S03). As a result, due to the centrifugal force caused by the rotation of the substrate W, IPA spreads over the entire area of the surface to be processed of the substrate W, and an alkali rinse process for replacing the DIW filled on the surface to be processed of the substrate W with IPA is performed. Further, here, since it is replaced with IPA having a lower surface tension than DIW, the surface tension acting between the patterns formed on the surface to be processed of the substrate W is reduced.

[0133] Then, as Figure 4 As shown in (A), while the driving mechanism 33 rotates the substrate W together with the support portion 32, the second volatile solvent supply portion 35 supplies PGMEA as the second volatile solvent H to the rotation center of the surface to be processed of the substrate W (step S04). As a result, due to the centrifugal force caused by the rotation of the substrate W, PGMEA spreads over the entire area of the surface to be processed of the substrate W, and HMDS binds to the surface to be processed of the substrate W to form a water-repellent film. That is, the first volatile solvent present on the surface to be processed of the substrate W is replaced with PGMEA of the second volatile solvent, and the hydroxyl groups on the surface to be processed are replaced with functional groups to form a water-repellent film. The second volatile solvent has a smaller surface tension acting between the patterns of the substrate W than the first volatile solvent. Therefore, the surface tension acting between the patterns is reduced. At the same time, the detection portion 38a of the measurement portion 38 measures the film thickness on the substrate W (step S06).

[0134] When the film thickness measured by the measurement portion 38 is appropriate within the specified threshold value (YES in step S07), as Figure 5 shown, while rotating the substrate W, the lamp 36a of the heating portion 36 is lit for a specified time (within a range of several seconds to ten-odd seconds), thereby rapidly heating the substrate W to a temperature at which the Leidenfrost phenomenon occurs (above the boiling point of PGMEA) (step S08). As a result, a drying process for instantaneously removing the liquid film of the second volatile solvent H is performed.

[0135] The drying process mentioned here is not caused by simple volatilization, but by utilizing the Leidenfrost phenomenon and the detachment of the hydrophobic film generated during the rapid heating process, as well as the centrifugal force caused by the rotation of the substrate W. That is, by utilizing the Leidenfrost phenomenon caused by the gas layer generated by heating at the interface between the treated surface of the substrate W and the liquid film of the PGMEA that is not completely vaporized, the liquid film floats up and becomes liquid beads (liquid beads). Thereafter, the bonding state of the hydrophobic film on the substrate W is released and removed. The mechanism of chemical bond release is as follows. First, by heating to a high temperature, the functional group (-CHx) cuts off the bond with Si by thermal decomposition, and the surrounding oxygen on the substrate W is bonded to the Si and the functional group on the substrate W. As a result, the Si on the substrate W is oxidized and the thermal oxidation film grows. That is, an oxide film is formed on the treated surface of the substrate W, but there is no particular problem with the residual oxide film. In addition, the functional group after oxidation will change to H2O or CO2, etc., but because it is at a high temperature, H2O evaporates and CO2 is discharged as a gas. Furthermore, during heating, the exhaust valve in the exhaust portion 31f may be closed to prevent the liquid film from evaporating before the gas layer is generated and thus preventing an overheated state from occurring.

[0136] If the phenomenon is schematically represented, Figure 7 As shown in (A), a liquid film F of PGMEA containing HMDS is present on a pattern P on a processed surface of a substrate W through a water-repellent film R. Figure 7 As shown in (B), only the substrate W is heated instantaneously by lighting of the lamp 36a, and the interface between the water-repellent film and PGMEA of the substrate W begins to vaporize earlier than PGMEA in other parts, thereby generating a gas layer G, which is a gas layer obtained by vaporizing the liquid film F.

[0137] Therefore, if Figure 7 As shown in (C), the liquid film F on the pattern P instantly floats from the pattern P through the gas layer G, as shown in FIG. Figure 7 As shown in (D), liquid beading (Leidenfrost phenomenon) is immediately performed, thereby cutting off the bond between Si and -CHx on the processed surface of the substrate W and removing the hydrophobic film R. In this way, after the liquid film F is beaded, the hydrophobic film R is removed from the substrate W. However, since the hydrophobic film R can be vaporized instantly (within a few seconds) at 300°C by the lamp 36a, it can be considered that the beading and the removal of the hydrophobic film R occur almost simultaneously. In the figure, as shown by the black arrow, the centrifugal force caused by the rotation is applied to the liquid film F, and the generated liquid beads fly away from the substrate W due to the centrifugal force. Therefore, as shown in FIG. Figure 7 As shown in (E), the processed surface of the substrate W is dried. In addition, as described above, since the functional group that cuts the bond with Si bonds with oxygen to form H2O or CO2, the silane coupling agent as a water-repellent agent evaporates, the atmosphere in the drying chamber 31 preferably contains oxygen.

[0138] like Figure 8As shown, if there is a liquid film F remaining between the patterns P on the substrate W, the patterns P in the portion where the liquid film F remains are attracted to each other due to the surface tension of the liquid film F, causing the patterns P to collapse. In the present embodiment, as shown in (A) of Figure 7 , on the entire substrate W, since there is a water-repellent film R on the surface of the pattern P, it is difficult to form a liquid film F between the patterns P, resulting in a state where it is difficult for a liquid film F to exist between the patterns P. Thus, since there is no liquid film F pulling the patterns P closer to each other, the collapse of the patterns P can be prevented. At the same time, the water-repellent film R is detached from the substrate W, and the unnecessary water-repellent film R can be removed from the surface of the substrate W to be processed. Therefore, the collapse of the patterns P can be reduced and the substrate W can be dried.

[0139] Thereafter, heating by the heating unit 36 is stopped, and the substrate W is placed while being rotated to perform cooling (step S09). After the rotation of the substrate W together with the support portion 32 is stopped by the drive mechanism 33 (step S10), the transfer device 200 transfers the substrate W out of the opening 31a (step S11).

[0140] [Effect]

[0141] (1) The drying device (substrate drying device) 300 of the present embodiment as described above includes: a heating unit 36 for heating the substrate W; a first volatile solvent supply unit 34 for supplying a first volatile solvent V to the surface of the substrate W to be processed; a second volatile solvent supply unit 35 for supplying a second volatile solvent H to the surface of the substrate W to be processed, the second volatile solvent H containing a water-repellent agent for forming a water-repellent film and having a smaller surface tension than the first volatile solvent V when vaporized; a drying chamber 31 for accommodating the heating unit 36, the first volatile solvent supply unit 34, and the second volatile solvent supply unit 35, and for loading the substrate W in a state where a liquid film formed by a processing liquid is formed on the surface to be processed; a support portion 32 for receiving the substrate W loaded into the drying chamber 31; a drive mechanism 33 for rotating the substrate W supported by the support portion 32; and a control device 400 for replacing the liquid film formed by the processing liquid on the surface of the substrate W with the first volatile solvent V by supplying the first volatile solvent V from the first volatile solvent supply unit 34, replacing the first volatile solvent V on the surface of the substrate W with the second volatile solvent H by supplying the second volatile solvent H from the second volatile solvent supply unit 35, and forming a water-repellent film on the surface to be processed, and generating an air layer between the liquid film of the second volatile solvent H containing the water-repellent agent and the substrate W by heating the substrate W with the heating unit 36, so as to discharge the liquid film of the second volatile solvent H by the centrifugal force generated by the rotation of the substrate W.

[0142] The substrate processing apparatus 1 of the present embodiment includes: a processing apparatus 110 that performs processing by rotating a substrate W and supplying a first processing liquid; a cleaning apparatus 120 that performs cleaning by rotating the substrate W processed by the processing apparatus 110 and supplying a second processing liquid; a drying apparatus 300; and a transfer apparatus 200 that transfers the substrate W cleaned by the cleaning apparatus 120 to the drying apparatus 300 in a state where a liquid film formed by the second processing liquid supplied by the cleaning apparatus 120 is formed.

[0143] In the substrate drying method of the present embodiment, a liquid film formed by a processing liquid is formed. While rotating the substrate W supported by the support portion 32 by the drive mechanism 33, the liquid film is replaced with the first volatile solvent V by supplying the first volatile solvent V from the first volatile solvent supply portion 34. The liquid film of the first volatile solvent V is replaced with the second volatile solvent H by supplying a second volatile solvent containing a water-repellent agent for forming a water-repellent film and having a surface tension smaller than that of the first volatile solvent V when vaporized, and a water-repellent film is formed on the substrate W. By heating the substrate W using the heating portion 36, an air layer is generated between the liquid film of the second volatile solvent H containing the water-repellent agent and the substrate W, and thus the liquid film of the second volatile solvent H is discharged by the centrifugal force generated by the rotation of the substrate W.

[0144] In this way, when heating while rotating the substrate W to an overheated state, since it is difficult to form a liquid film between the patterns due to the water-repellent film, and the liquid film is floated by the Leidenfrost phenomenon, the entire liquid film can be instantaneously removed by the centrifugal force.

[0145] Therefore, the substrate W can be dried in the same apparatus and the same processing chamber. There is no need for a removal apparatus such as a plasma processing apparatus or a UV irradiation apparatus independent of the drying apparatus 300 to remove the water-repellent film, and there is no need for a transfer process from the drying apparatus 300 to the removal apparatus. Therefore, the substrate processing apparatus 1 can be simplified and miniaturized, the number of processes can be reduced, and the productivity can be improved. Furthermore, it is also possible to remove the liquid film at the bottom of the pattern that is difficult to remove by UV irradiation.

[0146] In addition, since the entire liquid film of the second volatile solvent H can be instantaneously removed together with the water-repellent film, it is difficult to generate partial liquid film residues on the processed surface of the substrate W. Therefore, it is possible to reduce the difference in tension caused by the presence or absence and the amount of residual liquid film between adjacent patterns, and thus the possibility of pattern collapse. Furthermore, it is also possible to reduce the residual deviation of the liquid film caused by the difference in centrifugal force between the center and the periphery of the substrate W and the concentration of the liquid film toward the outer periphery.

[0147] (2) The substrate W is heated by the heating unit 36 to create an air layer between the liquid film of the second volatile solvent H supplied to the treated surface of the substrate W and the substrate W. At this time, the water-repellent film formed on the treated surface of the substrate W is removed from the treated surface of the substrate W. Therefore, the bonding of the water-repellent film can be released by heating, and the liquid film and the water-repellent film can be instantaneously removed by the centrifugal force generated by the rotation of the substrate W.

[0148] In addition, in order to separate the water-repellent film by heating, even if it is necessary to supply superheated liquid from the nozzle, a system for treating subcritical liquid is required. Therefore, the safety mechanism increases and the cost becomes high. However, in the present embodiment, by heating the substrate W using the heating unit 36 while rotating the substrate W, no additional device is required, and thus the liquid film can be instantaneously removed.

[0149] (3) There is a measuring unit 38 that measures the film thickness of the first volatile solvent on the substrate W supported by the supporting unit 32. When the control device 400 determines that the film thickness obtained by the measurement by the measuring unit 38, as the measurement result, is within the range of a specified threshold value, heating using the heating unit 36 is started. Thus, the liquid film on the substrate W can be adjusted to an appropriate film thickness, and then the substrate W is dried. If the film thickness is too thin, the liquid film on the treated surface of the substrate W during heating will dry unevenly, so pattern collapse of a part of the pattern will occur. In addition, if the film thickness is too thick, the number of liquid droplets increases. Therefore, before the liquid droplets are discharged out of the treated surface by the centrifugal force of the rotating substrate W, the contact portions in contact with the treated surface of the substrate W increase. Since the treated surface of the substrate W is cooled by the heat of vaporization when in contact with the liquid droplets, if the number of liquid droplets is too large, even during rapid heating, a portion below the temperature at which the Leidenfrost phenomenon occurs, that is, a portion dried by normal drying rather than rapid drying, will be generated on a part of the treated surface of the substrate W. In the present embodiment, since the substrate W is heated after being adjusted to an appropriate film thickness, such a drying state caused by normal drying can be prevented.

[0150] (Modification example)

[0151] (1) The first volatile solvent is not limited to IPA. For example, hydrogen fluoride ether (HFE) etc. can be used. The silane coupling agent as the water-repellent agent is not limited to HMDS. For example, tetramethyl silyl diethyl amine (TMSDEA) etc. can be used. The second volatile solvent is also not limited to the above-mentioned PGMEA. For example, IPA can also be used.

[0152] (2) Regarding the processing of the processing device 100, as long as the processing finally requires washing and drying, the content of the processing and the processing liquid are not limited to the examples described above. The substrate W to be processed and the processing liquid are also not limited to the examples described above.

[0153] [Other Embodiments]

[0154] The embodiments of the present invention and the modification examples of each part have been described above. However, the above-described embodiments or the modification examples of each part are presented as examples and are not intended to limit the scope of the invention. These novel embodiments described above can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope or gist of the invention and are included in the invention described in the claims.

Claims

1. A substrate drying device, characterized in that, comprising: a heating unit for heating a substrate; a first volatile solvent supply unit for supplying a first volatile solvent to a surface to be processed of the substrate; a second volatile solvent supply unit for supplying a second volatile solvent to the surface to be processed of the substrate, the second volatile solvent containing a water-repellent agent for forming a water-repellent film and having a surface tension smaller than that of the first volatile solvent when vaporized; a drying chamber housing the heating unit, the first volatile solvent supply unit, and the second volatile solvent supply unit, and into which the substrate having a liquid film formed by a processing liquid on the surface to be processed is carried; a support unit for receiving the substrate carried into the drying chamber; a driving mechanism for rotating the substrate supported by the support unit; and a control device for replacing the liquid film formed by the processing liquid on the surface to be processed of the substrate with the first volatile solvent by supplying the first volatile solvent from the first volatile solvent supply unit, replacing the first volatile solvent on the surface to be processed of the substrate with the second volatile solvent by supplying the second volatile solvent from the second volatile solvent supply unit, and forming the water-repellent film on the surface to be processed of the substrate, generating an air layer between the liquid film of the second volatile solvent containing the water-repellent agent and the substrate by heating the substrate with the heating unit, and discharging the liquid film of the second volatile solvent by the centrifugal force generated by the rotation of the substrate.

2. The substrate drying device according to claim 1, wherein Heating the substrate with the heating unit to generate an air layer between the liquid film of the second volatile solvent supplied to the surface to be processed of the substrate and the substrate, and removing the water-repellent film formed on the surface to be processed of the substrate from the surface to be processed of the substrate at this time.

3. The substrate drying apparatus according to claim 2, wherein, comprising a measuring unit for measuring the film thickness of the liquid films of the first volatile solvent and the second volatile solvent of the substrate supported by the support unit, the control device starting to heat with the heating unit when it is determined that the film thickness as the measurement result obtained by the measurement by the measuring unit is within a specified threshold range.

4. A substrate processing apparatus, characterized in that, comprising: a processing device for performing processing by supplying a first processing liquid while rotating the substrate; a cleaning device for performing cleaning by supplying a second processing liquid while rotating the substrate processed by the processing device; a substrate drying device according to any one of claims 1 to 3; and a transfer device for taking out and transferring the substrate cleaned by the cleaning device into the substrate drying device in a state where a liquid film formed by the second processing liquid supplied by the cleaning device is formed.

5. A substrate drying method, characterized in that: while the substrate having a liquid film formed by a processing liquid and supported by the support unit is rotated by the driving mechanism, the liquid film formed by the processing liquid is replaced with the first volatile solvent by supplying the first volatile solvent from the first volatile solvent supply unit, By supplying a second volatile solvent containing a water-repellent agent for forming a water-repellent film and having a surface tension smaller than that of the first volatile solvent when vaporized from a second volatile solvent supply unit, replacing the liquid film of the first volatile solvent with the second volatile solvent, and forming a water-repellent film on the substrate. By heating the substrate using a heating unit, an air layer is generated between the liquid film of the second volatile solvent containing the water-repellent agent and the substrate, and thus the liquid film of the second volatile solvent is discharged by the centrifugal force caused by the rotation of the substrate.

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