Substrate drying device, substrate processing device, and substrate drying method

Abstract

To provide a substrate drying device, a substrate processing device, and a substrate drying method that can reduce occurrence of pattern blockage on the entire surface layer of a substrate.SOLUTION: A drying device (substrate drying device) 300 includes a drying chamber 31 into which a substrate W having a liquid film of a processing liquid formed on a processing target surface thereof is conveyed, a support portion 34 for supporting the substrate W conveyed into the drying chamber 31, a flash lamp 321 that is provided in the drying chamber 31 and heats the surface layer of the processing target surface of the substrate W to a temperature equal to or higher than a temperature at which a gas layer is generated due to the Leidenfrost phenomenon in the entire area between the liquid film and the surface layer, a temperature maintenance unit (halogen lamp 322) that maintains the temperature of the surface layer by heating so as to maintain the gas layer by the heating of the flash lamp 321, and a drive mechanism 35 for rotating the substrate W together with the support portion 34 so that the liquid film having the gas layer generated between the liquid film and the surface layer is discharged by centrifugal force caused by the rotation of the substrate W.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] In the manufacturing process of semiconductors and liquid crystal panels, a substrate processing apparatus is used to supply a processing liquid to a processing surface of a substrate such as a wafer or liquid crystal substrate to process the processing surface, and then clean and dry the processing surface. In the drying process of the substrate processing apparatus, due to the spacing and structure of patterns formed on the surface layer of the processing surface, the surface tension of the processing liquid, etc., fine uneven patterns, for example, around memory cells and gates, may collapse and become blocked. This tendency is increasing with the miniaturization associated with the high integration and high capacity of semiconductors in recent years.

[0003] In order to prevent pattern collapse, a substrate drying method using IPA (2-propanol: isopropyl alcohol), which has a surface tension lower than that of ultrapure water, has been proposed. This substrate drying method replaces the DIW (ultrapure water) on the substrate surface with a mixture of IPA and DIW, and dries the substrate. However, semiconductors are becoming increasingly finer, and even when drying is performed using a highly volatile organic solvent such as IPA, the wafer pattern can still collapse due to the surface tension of the liquid.

[0004] For example, if the drying speed of the substrate surface becomes uneven as the liquid dries and liquid remains between some patterns, the surface tension of the liquid in those areas will cause the patterns to collapse. More specifically, the patterns in the areas where the liquid remains will collapse due to elastic deformation caused by the surface tension of the liquid, and the small amount of dissolved residue in the liquid will coagulate. Then, when the liquid has completely evaporated, the collapsed patterns will stick together.

[0005] To address this issue, a drying method has been proposed in which, after supplying the cleaning liquid, the surface layer of the surface to be treated of the rotating substrate is rapidly heated to a temperature at which the Leidenfrost phenomenon occurs, generating an air layer between the surface layer and the liquid film of the cleaning liquid, turning the liquid film into droplets, and expelling them from the substrate by the centrifugal force of rotation, thereby suppressing the collapse of fine patterns due to surface tension (see Patent Document 1). This drying method is not sufficient when it is in a nucleate boiling state in which minute air bubbles are generated inside the liquid film that is in direct contact with the heated surface; it is necessary to create a film boiling state in which a vapor film is interposed between the liquid and the heated surface, and evaporation occurs in the vapor film as a result of heat transfer from the heated surface through the vapor film. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6400919 Summary of the Invention [Problem to be solved by the invention]

[0007] As described above, even in the drying process in which the liquid film is turned into droplets and removed using the Leidenfrost phenomenon, some portions of the substrate may become blocked by the pattern. This is thought to be because a portion of the liquid film in contact with the surface layer of the substrate remains in a nucleate boiling state rather than a film boiling state, and the liquid film does not turn into droplets and remains between the projections and recesses of the pattern, and ultimately the surface tension acts in that portion, causing the pattern to become blocked.

[0008] In order to prevent such partial pattern blockage, the entire surface of the substrate must be instantaneously heated to a high temperature in order to bring the liquid film to a film boiling state over the entire surface of the substrate. More specifically, the surface of the substrate must be instantaneously heated to a temperature difference of more than 100°C with respect to the boiling point temperature of the liquid film in contact with it. Furthermore, the film boiling temperature must be maintained until the liquid droplets are discharged from the substrate.

[0009] Flash lamps and halogen lamps are heat sources that have been used conventionally in the field of semiconductors. However, although flash lamps can instantly heat the surface layer of the substrate in a few milliseconds, they cannot maintain the temperature at the film boiling state until the droplets are discharged from the substrate. On the other hand, halogen lamps take several seconds to heat the surface layer of the substrate, so their heating speed is slower than that of flash lamps, but once the temperature of the substrate reaches the film boiling state, they can maintain that temperature. However, in order to more stably turn the liquid film into droplets, it is necessary to increase the speed at which the halogen lamp heats up to the film boiling temperature to several milliseconds, which requires a huge output. In other words, a power source capable of producing a large output must be installed, and repeated heating would result in excessive power consumption, making this unrealistic.

[0010] An object of the present invention is to provide a substrate drying apparatus, a substrate processing apparatus and a substrate drying method that can reduce the occurrence of pattern blockage of the entire surface layer of a substrate. [Means for solving the problem]

[0011] The substrate drying apparatus of the present invention comprises a drying chamber into which a substrate having a liquid film formed on its processing surface by a processing liquid is carried, a support part for supporting the substrate carried into the drying chamber, a flash lamp provided within the drying chamber for heating a surface layer of the processing surface of the substrate to a temperature above a temperature at which an air layer occurs due to the Leidenfrost phenomenon between the entire surface layer and the liquid film, a temperature maintaining part for maintaining the temperature of the surface layer by heating so as to maintain the air layer caused by the heating of the flash lamp, and a drive mechanism for rotating the substrate together with the support part, thereby discharging the liquid film with the air layer formed between it and the surface layer by centrifugal force caused by the rotation of the substrate.

[0012] The substrate processing apparatus of the present invention includes a processing apparatus which processes a substrate by supplying a processing liquid while rotating the substrate, a cleaning apparatus which cleans the processed substrate by supplying a processing liquid while rotating the substrate, a substrate drying apparatus, and a transport apparatus which transports the substrate cleaned in the cleaning apparatus with a liquid film formed by the cleaning liquid thereon and transports the substrate into the substrate drying apparatus.

[0013] In the substrate drying method of the present invention, a support section supports a substrate which has been brought into a drying chamber with a liquid film of a processing liquid formed on its processing surface, a drive mechanism rotates the substrate together with the support section, a flash lamp heats a surface layer of the processing surface of the substrate to a temperature equal to or higher than a temperature at which an air layer occurs due to the Leidenfrost phenomenon between the liquid film and the entire surface layer, a temperature maintaining section maintains the temperature of the surface layer by heating so as to maintain the air layer caused by the heating of the flash lamps, and the liquid film is discharged by centrifugal force caused by the rotation of the substrate. Effect of the Invention

[0014] The present invention can provide a substrate drying apparatus, a substrate processing apparatus, and a substrate drying method that can reduce the occurrence of pattern blockage on the entire surface layer of a substrate. [Brief description of the drawings]

[0015] [Figure 1] 1 is a simplified configuration diagram showing a substrate processing apparatus according to an embodiment; [Diagram 2] 2 is a configuration diagram showing a cleaning device and a drying device of the substrate processing apparatus of FIG. 1. [Diagram 3] 1A is a diagram showing the internal configuration of the drying device when a substrate is carried in and FIG. 1B is a diagram showing the internal configuration of the drying device when a film thickness is measured. [Figure 4] 1A is a diagram showing the internal configuration of the drying device when a cleaning liquid is being supplied and when the drying device is on standby for a substrate; FIG. [Diagram 5] 1C is a diagram showing the internal configuration of the drying device when drying a substrate, and FIG. 1B is a diagram showing the internal configuration of the drying device when the substrate is lowered. [Figure 6] 4 is a flowchart showing a procedure of a substrate drying process according to an embodiment. [Figure 7]FIG. 1 is an explanatory diagram showing the flow of a drying process utilizing the Leidenfrost phenomenon. [Figure 8] FIG. 13 is an explanatory diagram showing a liquid film remaining in a pattern. [Figure 9] 4 is a graph showing temperature changes of a flash lamp, a halogen lamp, and a substrate. [Figure 10] FIG. 13 is a configuration diagram showing a modified example of the temperature maintaining unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. [overview] 1, the substrate processing apparatus 1 of this embodiment is a single-wafer processing apparatus having multiple chambers 1a housing various processing devices, and processes substrates W, which have been stored in a cassette (FOUP) 1b in a previous process and transported, one by one in each chamber 1a. Unprocessed substrates W are taken out of the cassette 1b one by one by a transport robot 1c, temporarily placed in a buffer unit 1d, and then transported to each chamber 1a and processed by various devices described below.

[0017] The substrate processing apparatus 1 includes a processing apparatus 110, a cleaning apparatus 120, a transport apparatus 200, a drying apparatus 300, and a control apparatus 400. The processing apparatus 110 is, for example, an etching apparatus that supplies a processing liquid (for example, an aqueous phosphoric acid solution, a mixed liquid of hydrofluoric acid and nitric acid, a mixed liquid of acetic acid, sulfuric acid, and hydrogen peroxide (SPM: Sulfuric hydrogen peroxide mixture), etc.) to a rotating substrate W to remove unnecessary films and leave a circuit pattern. The cleaning apparatus 120 cleans the substrate W that has been etched in the etching apparatus with a processing liquid (cleaning liquid).

[0018] The transport device 200 transports the substrate W between the buffer unit 1d and each chamber 1a and between each chamber 1a. For example, the transport device 200 transports the substrate W that has been processed in the processing device 110 to the cleaning device 120, and transports the substrate W that has been cleaned in the cleaning device 120 to the drying device 300. The drying device (substrate drying device) 300 performs a drying process by heating the substrate W that has been cleaned with a cleaning liquid while rotating it. The control device 400 controls each of the above devices.

[0019] The substrate W to be processed in 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 referred to as the processed surface. In addition, on the processed surface of the substrate, the outermost surface of the pattern that is in contact with the liquid film of the processing liquid is referred to as the surface layer.

[0020] The cleaning liquids used in the cleaning process are alkaline cleaning liquid (APM), ultrapure water (DIW), and volatile solvent (IPA). APM is a chemical solution made by mixing ammonia water and hydrogen peroxide, and is used to remove residual organic matter. DIW is used to wash away the APM remaining on the processed surface of the substrate W after APM processing. IPA has a smaller surface tension than DIW and is highly volatile, so it is used to replace DIW and reduce pattern collapse caused by surface tension.

[0021] [Cleaning equipment] 2, the cleaning apparatus 120 has a cleaning chamber 11 which is a container in which a cleaning process is performed, a support part 12 which supports the substrate W, a rotation mechanism 13 which rotates the support part 12, a cup 14 which receives the scattering cleaning liquid L from around the substrate W, and a supply part 15 which supplies the cleaning liquid L. The supply part 15 is provided with a nozzle 15a which drips the cleaning liquid L, and a movement mechanism 15b which moves the nozzle 15a.

[0022] A cleaning process is performed by supplying the cleaning liquid L from the nozzle 15a to the processing surface of the substrate W supported by the support part 12 and rotated by the rotation mechanism 13. In the cleaning process, APM is supplied to the processing surface of the substrate W etched in the processing device 110 to perform APM cleaning, and after the APM cleaning, a pure water rinse process is performed using DIW to wash away the APM remaining on the processing surface of the substrate W with pure water. As a result, the processing surface of the substrate W is filled with the cleaning liquid L of DIW. Furthermore, the DIW is finally replaced with IPA. The cleaning chamber 11 is provided with an opening 11a through which the substrate W is carried in and out, and the opening 11a is configured to be openable and closable by a door 11b.

[0023] [Transportation device] The transport device 200 has a handling device 20. The handling device 20 has a robot hand 21 that grips the substrate W, and a moving mechanism 22. The robot hand 21 grips the substrate W. The moving mechanism 22 moves the robot hand 21. The transport device 200 transports the substrate W between the buffer unit 1d and various devices, and between various devices. For example, the substrate W that has been subjected to etching processing is transported out of the processing device 110, and is transported into the cleaning device 120 in a state in which a liquid film of the cleaning liquid L is formed on the processing surface of the substrate W.

[0024] Moreover, the moving mechanism 22 moves the handling device 20 and the robot hand 21 to transport the substrate W after cleaning out of the cleaning device 120 and transport it into the drying device 300 in a state in which a liquid film of the cleaning liquid L is formed on the processing surface of the substrate W. The substrate W is transported in a state in which a liquid film of the cleaning liquid L is formed on the processing surface of the substrate W in order to prevent particles from adhering to the processing surface of the substrate W during transportation.

[0025] [Drying equipment] As shown in FIG. 1, the drying apparatus 300 includes a drying chamber 31, a heating section 32, a window section 33, a support section 34, a driving mechanism 35, a cup 36, a measuring section 37, and a supply section 38. The drying chamber 31 is a container for drying a substrate W therein. The substrate W having a liquid film of a processing liquid formed on the processing surface is carried into the drying chamber 31. The drying chamber 31 has a box shape such as a rectangular parallelepiped or a cube. The inner wall of the drying chamber 31 is coated with silica to improve dust resistance. The drying chamber 31 is provided with an opening 31a for carrying the substrate W in and out. The opening 31a is provided so as to be openable and closable by a door 31b.

[0026] The drying chamber 31 is provided with an inlet 31c and an exhaust port 31d. The inlet 31c is connected to a piping, an intake valve, and a clean gas (N 2 An air supply section 31e including an air supply device that supplies air (e.g., air, gas, etc.) is connected to the exhaust port 31d. An exhaust section 31f including a pipe, an exhaust valve, and an exhaust device that exhausts gas is connected to the exhaust port 31d. By supplying clean gas into the drying chamber 31 from the inlet 31c, the atmosphere inside the drying chamber 31 can be made clean. In addition, a gas flow inside the drying chamber 31 is created by providing a configuration in which gas is supplied into the drying chamber 31 from the inlet 31c and the gas inside the drying chamber 31 is exhausted from the exhaust port 31d. This allows the vapor of the processing liquid generated when the substrate W is heated to be exhausted from the drying chamber 31 without filling the drying chamber 31. The exhaust section 31f may be provided with a rapid exhaust valve that reduces the pressure of the atmosphere that rapidly expands due to a flash of light emitted from a flash lamp 321 described later.

[0027] The heating section 32 is a device for heating the substrate W. The heating section 32 is provided in the upper part of the drying chamber 31. The heating section 32 has a flash lamp 321 and a halogen lamp 322. A partition window 32a, which is a plate-shaped body made of quartz or the like, is provided between the flash lamp 321 and the halogen lamp 322. The flash lamp 321 is of a straight tube type, and a plurality of flash lamps are arranged horizontally in parallel. A power source and a capacitor (not shown) are connected to the flash lamp 321, and the flash lamp 321 can instantly emit light and heat to a high temperature by the energy stored in the capacitor. The flash lamp 321 of this embodiment heats the surface layer of the substrate W to a temperature (hereinafter referred to as the Leidenfrost temperature) or higher at which an air layer due to the Leidenfrost phenomenon occurs in the entire area between the liquid film and the surface layer. The Leidenfrost temperature is a temperature range having a different width depending on the type and thickness of the liquid film.

[0028] The halogen lamps 322 are temperature maintaining units that maintain the temperature of the surface layer by heating so as to maintain the gas layer generated by the heating of the flash lamps 321. The halogen lamps 322 are straight tube type, and a plurality of them are arranged horizontally above the flash lamps 321 in a direction perpendicular to the flash lamps 321. A power source (not shown) is connected to the halogen lamps 322. Both the flash lamps 321 and the halogen lamps 322 can use a general factory power source of 200V or less.

[0029] The flash lamps 321 and the halogen lamps 322 are arranged in perpendicular directions, forming a lattice pattern as a whole. The flash lamps 321 and the halogen lamps 322 use electromagnetic waves (infrared rays) of a wavelength that is more likely to heat the surface layer of the substrate W than the cleaning liquid L itself, thereby promoting the generation of a gas layer due to the heat of the substrate W.

[0030] More specifically, the entire surface of the substrate W on which the IPA liquid film exists is heated to 200°C or higher within several milliseconds. This causes the liquid film to enter a film boiling state, and the contact portion of the liquid film with the substrate W is instantly and uniformly vaporized to generate a gas layer, allowing the liquid film to float up. Since the flash lamps 321 cannot be turned on for a long period of time, the surface of the substrate W is heated by the halogen lamps 322 to continue vaporizing the floated liquid near the substrate W, thereby preventing reattachment to the surface of the substrate W and removing the liquid film without the action of surface tension.

[0031] The window 33 is a member that transmits electromagnetic waves from the heating unit 32. For example, a plate-like body such as quartz can be used as the window 33. The window 33 is provided directly below the heating unit 32 in the drying chamber 31, and separates the heating unit 32 from the support unit 34, thereby preventing particles generated by the expansion and contraction of the members of the connector unit due to repeated lighting of the flash lamps 321 and the halogen lamps 322 from adhering to the substrate W from above and causing metal contamination.

[0032] The support unit 34 supports the substrate W carried into the drying chamber 31. The support unit 34 has a rotating table 34a, a plurality of holding members 34b, and a rotating shaft 34c. The rotating table 34a is cylindrical with a diameter larger than the substrate W, and has a flat circular upper surface. The plurality of holding members 34b are arranged at equal intervals along the outer periphery of the substrate W, and hold the substrate W in a horizontal state with a gap between the substrate W and the upper surface of the rotating table 34a. The plurality of holding members 34b are provided so as 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 34c is a vertical axis that supports the rotating table 34a from below and serves as the center of rotation.

[0033] The driving mechanism 35 is a mechanism for rotating and lifting the substrate W supported by the support parts 34. The driving mechanism 35 has a rotating part 35a and a lifting part 35b. The rotating part 35a has a driving source such as a motor, and rotates the support parts 34 via a rotating shaft 34c. The lifting part 35b has a mechanism for lifting a slider by a ball screw rotated by the motor, and together with the rotating part 35a, moves the support parts 34 up and down.

[0034] In this embodiment, a waiting position D and a drying position U are set as positions of the support part 34 that are changed by the drive mechanism 35. The waiting position D is a position for receiving, away from the heating part 32, the substrate W that has been carried into the drying chamber 31 with a liquid film of the cleaning liquid L formed thereon.

[0035] More specifically, the waiting position D is lower than the detection unit 37a and the nozzle 38a described below. The reason why the substrate W is received and supported at a position separated from the heating unit 32 in this manner is as follows. That is, even if the heating unit 32 heats the substrate W (lamp is turned on) only during the drying process, the window unit 33 accumulates heat due to the heat generated by the heating unit 32. In particular, the window unit 33 is more likely to accumulate heat because it is located directly below the heating unit 32 and is made of quartz, which has poor thermal conductivity. For this reason, repeated drying processes cause heat accumulation in the window unit 33.

[0036] When a substrate W on which a film of cleaning liquid L has been formed is carried in under such an environment, the liquid film on the substrate W starts to evaporate due to radiant heat from the window portion 33 that has stored heat. However, the entire liquid film does not evaporate instantly, but a non-uniform drying state occurs in which only a portion evaporates, and pattern blockage occurs due to the surface tension of the remaining cleaning liquid L. For this reason, it is necessary to support the substrate W at a position separated from the heating portion 32 to prevent it from being affected by such radiant heat.

[0037] Therefore, the waiting position D is a position away from the window portion 33 until the processing liquid piled on the processing surface of the substrate W (the processing liquid at the time of being carried into the drying chamber 31) reaches a state where there is no risk of evaporation (the influence of heat is small) due to the radiant heat of the window portion 33 which is repeatedly heated and stored by the heating portion 32. The drying position U is a position close to the heating portion 32 where the substrate W heated by the heating portion 32 generates an air layer between itself and the liquid film. In this embodiment, the waiting position D is below the upper edge E of the opening 31a, and the drying position U is above the upper edge E of the opening 31a.

[0038] The cup 36 is formed in a cylindrical shape so as to surround the support part 34 (see FIG. 2). The upper part of the peripheral wall of the cup 36 is inclined radially inward and opens so as to expose the substrate W on the support part 34. The cup 36 receives the cleaning liquid L scattered from the rotating substrate W and allows it to flow downward. A drain port (not shown) is formed in the bottom surface of the cup 36 for discharging the cleaning liquid L that flows down. The cup 36 is connected to the drive mechanism 35 and is provided so as to be able to move up and down together with the support part 34.

[0039] The measuring unit 37 is carried into the drying chamber 31 and measures the thickness of the liquid film on the substrate W at the waiting position D. The measuring unit 37 has a detecting unit 37a, a swinging arm 37b, and a swinging mechanism 37c. For example, a laser displacement meter or a camera is used as the detecting unit 37a. The swinging arm 37b has the detecting unit 37a at its tip, and moves the detecting unit 37a to a measuring position where it faces the vicinity of the center between the center and the outer periphery of the processing surface of the substrate W on the support unit 34, and to a waiting position where it is retreated from the measuring position and the substrate W can be loaded or unloaded. The swinging mechanism 37c is a mechanism that swings the swinging arm 37b.

[0040] For example, the principle of optical interference can be used as a film thickness measurement method by the measuring unit 37. As another example, a weight scale can be used in the supporting unit 34. When using this weight 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 theoretically or experimentally converted into the thickness of the liquid film.

[0041] The supply unit 38 is carried into the drying chamber 31 and supplies the cleaning liquid L onto the substrate W which is in the standby position D. The supply unit 38 has a nozzle 38a, a swinging arm 38b, and a swinging mechanism 38c. The nozzle 38a supplies the cleaning liquid L toward near the center of the processing surface of the substrate W. The cleaning liquid L is supplied to the nozzle 38a from a reservoir outside the drying chamber 31 via piping (neither of which is shown) or the like.

[0042] The type of cleaning liquid L supplied by the supply unit 38 is determined by the type of liquid that is finally piled on the substrate W in the rinsing process after alkaline cleaning in the cleaning process in the cleaning apparatus 120. That is, when the rinsing process is completed with DIW, the substrate W is transported from the cleaning apparatus 120 to the drying apparatus 300 in a state where the substrate W is piled with DIW. In the case of DIW, the supply unit 38 supplies DIW. When the DIW is finally replaced with IPA, the substrate W is transported from the cleaning apparatus 120 to the drying apparatus 300 in a state where the substrate W is piled with IPA. In the case of IPA, the supply unit 38 supplies new IPA because IPA evaporates during transport or absorbs moisture from the air during transport.

[0043] The swing arm 38b has a nozzle 38a at its tip, and moves the nozzle 38a between a supply position facing the vicinity of the center of the processing surface of the substrate W on the support part 34 and a retreat position from the supply position to enable loading and unloading of the substrate W. The swing mechanism 38c is a mechanism for swinging the swing arm 38b. The drying position U is located above the supply part 38 which is at the supply position where the cleaning liquid L is supplied to the substrate W.

[0044] [Control device] The control device 400 is a computer that controls each part of the substrate processing apparatus 1. The control device 400 has a processor that executes a program, a memory that stores various information such as the program and operating conditions, and a drive circuit that drives each element. That is, the control device 400 controls the processing apparatus 110, the cleaning apparatus 120, the transport apparatus 200, and the drying apparatus 300. The control device 400 has an input device for inputting information and a display device for displaying information.

[0045] The 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 unit. For example, the mechanism control unit 41 controls the rotation speed of the support unit 34 and the timing of starting and stopping the rotation by controlling the rotation unit 35a of the drive mechanism 35. In addition, the mechanism control unit 41 controls the distance (gap) between the support unit 34 and the heating unit 32 by controlling the elevation unit 35b of the drive mechanism 35.

[0046] More specifically, the control device 400 holds the substrate W on the support part 34 at the waiting position D, adjusts the thickness of the liquid film of the cleaning liquid L piled on the processing surface of the substrate W, and then moves the substrate W up to the drying position U while rotating it, and turns on the flash lamps 321 and the halogen lamps 322 to dry it for a predetermined period of time. Thereafter, while continuing to rotate the substrate W, it moves it down to the waiting position D. In addition, it controls the operation of the nozzle 38a to swing and discharge the cleaning liquid L, and the detection part 37a to swing and measure, etc.

[0047] The film thickness analysis unit 42 analyzes the thickness of the liquid film of the cleaning liquid L measured by the measurement unit 37. The film thickness analysis unit 42 judges whether or not the thickness of the liquid film of the cleaning liquid L measured by the measurement unit 37 (liquid film thickness value) is within a predetermined threshold range. If the film thickness analysis unit 42 judges that the measured thickness of the liquid film is within the predetermined threshold range, it determines that the thickness of the liquid film is appropriate and transmits an enabling signal to the mechanism control unit 41 to permit rotation and lifting of the substrate W. Upon receiving the enabling signal, the mechanism control unit 41 transmits a signal to the drive mechanism 35 to command the support unit 34 to rotate and lift.

[0048] The appropriate film thickness is, for example, 10 μm or less in the case of DIW, and 100 μm or less in the case of IPA. These film thicknesses are the liquid film thicknesses that do not evaporate from the substrate W when approaching the heating unit 32 (when approaching the window unit 33), and that allow satisfactory drying when performing drying processing by the Leidenfrost phenomenon. However, these numerical values ​​are examples, and in practice, appropriate liquid film thicknesses can be obtained in advance by experiments, etc. The rotation speed of the substrate W is, for example, about 200 to 300 rpm, and even if the liquid film is adjusted, the liquid film thickness can be maintained at a predetermined thickness within such a rotation speed range.

[0049] The heating control unit 43 controls the heating unit 32 in response to a command from the mechanism control unit 41. When the supporting unit 34 reaches the drying position U and stops, the heating control unit 43 receives a command signal output from the mechanism control unit 41 and causes the heating unit 32 to heat the processing surface of the substrate W on the supporting unit 34.

[0050] The heating control unit 43 causes the flash lamps 321 and the halogen lamps 322 to emit light simultaneously. Then, the light emitted by the flash lamps 321 rapidly heats the entire area between the liquid film and the surface layer on the processing surface of the substrate W to a temperature equal to or higher than the Leidenfrost temperature. For example, by heating at a temperature of 200° C. or higher, the entire surface layer of the substrate W is heated within a few milliseconds to a temperature equal to or higher than the temperature at which the liquid film enters a film boiling state. Note that the halogen lamps 322 may emit light before the flash lamps 321 emit light. In other words, the temperature maintaining unit may start heating before the flash lamps 321 emit light.

[0051] Then, as the temperature of the halogen lamps 322 that continue to emit light increases, the surface layer of the substrate W is maintained at a temperature equal to or higher than the Leidenfrost temperature, and the film boiling state is maintained. As a result, the cleaning liquid L on the surface layer of the processing surface of the substrate W turns into liquid droplets.

[0052] When the film thickness analysis unit 42 determines that the measured thickness of the liquid film of the cleaning liquid L is thinner than the lower limit of a range of a predetermined threshold value, it determines that the liquid film is too thin, and an instruction to supply a processing liquid (cleaning liquid L) is output from the mechanism control unit 41 to the supply unit 38. As a result, a predetermined amount (predetermined time) of the cleaning liquid L is supplied from the nozzle 38a to the processing surface of the substrate W, and the thickness of the liquid film is set within the predetermined threshold value range. Thereafter, the substrate W is rotated and lifted to be dried, as described above. The substrate W may be stopped without rotating when refilling with the cleaning liquid L, or the substrate W may be rotated.

[0053] When the film thickness analysis unit 42 determines that the measured thickness of the liquid film of the cleaning liquid L is thicker than the upper limit of a predetermined threshold range, it determines that the liquid film is too thick, and an instruction to rotate the support unit 34 is output from the mechanism control unit 41 to the drive mechanism 35. As a result, the cleaning liquid L on the substrate W rotating together with the support unit 34 is scattered by centrifugal force, and the thickness of the liquid film is adjusted to within the predetermined threshold range. Thereafter, the substrate W is rotated and raised to be dried as described above.

[0054] [Operation] The operation of the substrate processing apparatus 1 of this embodiment as described above will be described with reference to the explanatory diagrams of Figures 3 to 5, the flow chart of Figure 6, and the explanatory diagram of Figure 7 in addition to Figures 1 and 2. Note that a substrate manufacturing method for manufacturing a substrate W, a substrate drying method for drying a substrate W, and a substrate processing method for processing a substrate W by the following procedures are also aspects of this embodiment. Also, the cup 36 is not shown in Figures 3 to 5.

[0055] 2, the substrate W after etching in the processing device 110 is carried into the cleaning device 120 by the transport device 200. In the cleaning device 120, while the support part 12 holding the substrate W rotates, the supply part 15 supplies APM to the processing surface of the substrate W to perform alkaline cleaning, and then supplies DIW to perform pure water cleaning. After the pure water cleaning is completed, IPA is supplied to the processing surface of the substrate W.

[0056] As a result, the IPA spreads over the entire surface of the substrate W due to the centrifugal force generated by the rotation of the substrate W, and an alcohol rinse process is performed in which the DIW puddled on the surface of the substrate W is replaced with IPA. Note that, since the DIW is replaced with IPA, which has a lower surface tension than the DIW, the surface tension acting between the patterns formed on the surface of the substrate W is reduced.

[0057] The transport device 200 carries the cleaned substrate W out of the cleaning device 120 and into the drying device 300. After the deionized water cleaning is completed, the DIW puddled on the processing surface of the substrate W is not necessarily replaced with IPA. In other words, the cleaning process may be completed only by deionized water cleaning using DIW.

[0058] 3(A), with a liquid film (IPA) of cleaning liquid L formed on the processing surface, the substrate W is carried in through the opening 31a of the drying chamber 31 of the drying apparatus 300 and is held by the holding member 34b of the support unit 34 at the waiting position D (step S01). As shown in FIG. 3(B), the detection unit 37a of the measurement unit 37 measures the film thickness on the substrate W (step S02).

[0059] 4A, the supply unit 38 further supplies the cleaning liquid L to the liquid film on the substrate W to adjust the film thickness (step S04). If the film thickness is thick (exceeding the predetermined range in step S03), the support unit 34 rotates to splash the cleaning liquid L from the rotating substrate W to adjust the film thickness (step S05).

[0060] If the film thickness is appropriate or if the film thickness becomes appropriate after the adjustment (within a predetermined range in step S03), the support part 34 rotates the substrate W (step S06) as shown in Fig. 4(B), and moves up to a drying position U as shown in Fig. 5(A) to bring the substrate W closer to the heating part 32 (step S07). By rotating the substrate W before it is heated by the heating part 32, the liquid film of the cleaning liquid L on the processing surface of the substrate W is rotated together with the substrate W, so that even after the substrate W is heated by the heating part 32 and an air layer is generated between the substrate W and the processing surface of the substrate W, the liquid film of the cleaning liquid L continues to rotate due to inertial force, and centrifugal force acts.

[0061] The flash lamps 321 and halogen lamps 322 of the heating unit 32 emit light simultaneously to heat the surface layer of the substrate W (step S08). At this time, the flash lamps 321 emit light for several milliseconds to rapidly heat the entire surface layer of the substrate W to the Leidenfrost temperature or higher, and the Leidenfrost phenomenon causes the liquid film to float from the surface layer via a gas layer generated at the interface between the surface layer of the substrate W and the liquid film. The halogen lamps 322 continue to emit light for several seconds and then turn off, thereby heating the entire surface layer of the substrate W so that the temperature is maintained at or above the Leidenfrost temperature even after the flash lamps 321 are turned off.

[0062] As a result, the liquid film is maintained floating from the entire surface of the substrate W, forming liquid droplets, which are then blown off by centrifugal force and dried (step S09). That is, as shown in FIG. 7(A), the cleaning liquid L in contact with the pattern P on the processing surface of the substrate W starts to evaporate at the interface between the surface of the substrate W and the cleaning liquid L earlier than the cleaning liquid L in other parts as the substrate W is instantly heated only by turning on the flash lamps 321 as shown in FIG. 7(B), and a layer of gas in which the liquid (cleaning liquid L) is evaporated, that is, a gas layer G, is generated around the pattern P. Then, the temperature of the surface of the substrate W is maintained by keeping the halogen lamps 322 turned on, and the gas layer G is maintained. In addition, in FIGS. 7(B), (C), and (D), the pattern P of the substrate W is hatched with fine diagonal lines to indicate that the substrate W is rapidly heated and maintained.

[0063] As shown in Fig. 7(C), the liquid (cleaning liquid L) between adjacent patterns P is instantly lifted from between the patterns P by the gas layer G, and immediately turns into liquid droplets due to the Leidenfrost phenomenon as shown in Fig. 7(D) (Leidenfrost phenomenon). As shown by the black arrows in the figure, centrifugal force due to rotation is applied to the cleaning liquid L, and each generated liquid droplet is blown off from the substrate W by the centrifugal force, so that the processed surface of the substrate W dries as shown in Fig. 7(E).

[0064] In this way, the cleaning liquid L present between the patterns P is caused to float up from between the patterns P over the entire processed surface of the substrate W, and re-adhesion is prevented, thereby preventing the cleaning liquid L from remaining between some of the patterns P. Since the drying speed of the liquid on the processed surface of the substrate W becomes uniform, the collapse of the patterns P due to the collapsing force of the remaining liquid (e.g., surface tension) can be prevented.

[0065] If the liquid film is insufficient in thickness and dries by normal drying before the Leidenfrost phenomenon occurs, the surface tension acting on the cleaning liquid L remaining between some of the patterns P will cause the patterns to collapse, as shown in Fig. 8. In this embodiment, the liquid film thickness of the cleaning liquid L on the processing surface of the substrate W is adjusted to an appropriate thickness, so that the liquid film is maintained while the Leidenfrost phenomenon is occurring, and the liquid film floated by the air layer is removed from between the patterns P by centrifugal force, thereby preventing the patterns from collapsing due to the surface tension.

[0066] 5(B), the support 34 descends to the waiting position D while maintaining the rotation of the substrate W (step S10). After the support 34 stops the rotation of the substrate W (step S11), the transport device 200 transports the substrate W out of the opening 31a (step S12).

[0067] [effect] (1) The drying apparatus (substrate drying apparatus) 300 of this embodiment as described above comprises a drying chamber 31 into which a substrate W having a liquid film of the processing liquid formed on its surface to be processed is carried, a support part 34 that supports the substrate W carried into the drying chamber 31, flash lamps 321 provided within the drying chamber 31 for heating the surface layer of the surface to be processed of the substrate W to a temperature above a temperature at which an air layer occurs due to the Leidenfrost phenomenon between the liquid film and the entire surface layer, a temperature maintaining part (halogen lamp 322) for maintaining the temperature of the surface layer by heating so as to maintain the air layer generated by the heating of the flash lamps 321, and a drive mechanism 35 for rotating the substrate W together with the support part 34, thereby discharging the liquid film with an air layer formed between it and the surface layer by centrifugal force generated by the rotation of the substrate W.

[0068] The substrate processing apparatus 1 of this embodiment includes a processing apparatus 110 that supplies a processing liquid while rotating the substrate W, a cleaning apparatus 120 that cleans the processed substrate by supplying a processing liquid while rotating the substrate W, and a transport apparatus 200 that transports the substrate W cleaned in the cleaning apparatus 120 with a liquid film formed by the processing liquid thereon, and transports the substrate W into a drying apparatus 300.

[0069] In the substrate drying method of the present embodiment, the support part 34 supports the substrate W that has been brought into the drying chamber 31 with a liquid film of the processing liquid formed on the processing surface, the drive mechanism 35 rotates the substrate W together with the support part 34, the flash lamps 321 instantaneously heat the surface layer of the processing surface of the substrate W to a temperature above the temperature at which an air layer occurs due to the Leidenfrost phenomenon between the entire area between the liquid film and the surface layer, and the temperature maintenance part (halogen lamps 322) maintains the temperature of the surface layer by heating so as to maintain the air layer heated by the flash lamps 321, and the liquid film is expelled by centrifugal force caused by the rotation of the substrate W.

[0070] In this way, the flash lamps 321, which can emit light only for a short time but can instantly heat to a high temperature, heat the surface of the substrate W to the Leidenfrost temperature or higher to float the liquid film, and the temperature maintaining unit (halogen lamps 322) can maintain the Leidenfrost temperature, so that the liquid film floated by the gas layer does not reattach to the surface layer and can be removed from the substrate W, preventing pattern collapse due to remaining liquid. Also, compared to when a film boiling state is created using only the halogen lamps 322, the liquid film can be stably brought to a film boiling state and turned into liquid droplets without using a huge amount of power.

[0071] 9 is a graph with time on the horizontal axis and temperature on the vertical axis, which diagrammatically shows the temperature changes of the flash lamps 321, the halogen lamps 322, and the substrate W. When heating is performed only with the flash lamps 321, the surface layer of the substrate can be instantaneously heated to the Leidenfrost temperature (two-dot chain line in the figure) or higher, as indicated by the dashed line in the figure, but the temperature at which the film boiling state occurs cannot be maintained until the liquid droplets are discharged. On the other hand, when heating is performed only with the halogen lamps 322, as indicated by the one-dot chain line in the figure, it takes longer to raise the temperature than with the flash lamps 321, so the entire surface layer cannot be instantaneously heated to the Leidenfrost temperature or higher, and redeposition of the liquid droplets onto the surface layer occurs.

[0072] In this embodiment, even after the flash lamps 321 are turned off, the halogen lamps 322 continue to heat the substrate W, so that the average temperature of the substrate W can be maintained at or above the Leidenfrost temperature, as shown by the solid line in the figure. That is, the liquid film can be instantaneously brought to a temperature at which the film boiling state is reached, and then the temperature can be maintained. The time required for the instantaneous state, that is, the film boiling state, is preferably 3 msec or less. This allows only the surface layer of the liquid film to be brought to a film boiling state in a very short time. In this way, the surface layer of the liquid film on the entire surface of the substrate W does not remain in a nucleate boiling state, but is instantly brought to a film boiling state, so that the liquid film is more likely to form droplets. In addition, after the film boiling state is instantaneously reached, the film boiling state can be maintained. More specifically, by setting the temperature of the substrate W to a temperature higher than the Leidenfrost temperature (for example, 100° C. or higher), the liquid film on the entire surface of the substrate W can be stably maintained in a film boiling state. For this reason, after the liquid film transitions from a state in which it is attached to the surface layer in region α in the figure to region β where the liquid film floats up from the surface layer due to the Leidenfrost phenomenon, re-adhesion of the liquid film is prevented. Therefore, while preventing a decrease in temperature of the substrate W due to turning off the flash lamps 321, it is possible to realize a drying process using the Leidenfrost phenomenon without needing to heat the halogen lamps 322 to an extremely high temperature.

[0073] If the flash lamps 321 can heat the substrate W to a temperature of about 300° C. in less than one second, the liquid film on the surface of the substrate W can go through a nucleate boiling state (without remaining in the nucleate boiling state) and immediately reach a film boiling state. Also, based on Fig. 9, if the maximum heating temperature of the flash lamps 321 is set to a temperature about two to three times the Leidenfrost temperature, the liquid film on the surface of the substrate W can reach a film boiling state without remaining in the nucleate boiling state.

[0074] Here, the flash lamp 321 needs to be heated instantaneously to the Leidenfrost temperature, so high energy is required. To create this state, the pulse width can be reduced to emit light instantaneously with high energy.

[0075] 9, the heating temperature of the halogen lamps 322 rises to the Leidenfrost temperature in about one second. In other words, after the flash lamps 321 stop emitting light, the average substrate temperature drops, but because the halogen lamps 322 reach the Leidenfrost temperature in about one second, the average substrate temperature can be maintained at the Leidenfrost temperature.

[0076] (2) The temperature maintaining unit (halogen lamp 322) starts heating before or at the same time as the flash lamp 321 emits light. Therefore, even if the temperature rise of the temperature maintaining unit is slow, heating to the Leidenfrost temperature or higher is possible when the flash lamp 321 is turned off.

[0077] (3) The temperature maintaining unit (halogen lamp 322) continues heating even after the flash lamp 321 is turned off. This prevents cooling due to the turning off of the flash lamp 321, and makes it possible to maintain the Leidenfrost temperature.

[0078] (Modification) (1) The flash lamp 321 and the temperature maintaining unit may be disposed on opposite sides of the substrate W. For example, as shown in Fig. 10, the flash lamp 321 may be provided on the ceiling side of the drying chamber 31, and the halogen lamp 322 may be provided on the floor side across the substrate W. In this embodiment, the halogen lamp 322 is fixedly supported by a support stand 322a. An annular hollow motor 341 is installed on the floor of the drying chamber 31. A stator 341a made of a coil is formed on the fixed side of the hollow motor 341, and a rotor 341b made of a magnet is provided on the rotating side.

[0079] The rotor 341b is provided with a plurality of holding members 34b. Thus, the substrate W held by the holding members 34b is disposed at a distance from the support table 322a and rotates together with the rotation of the rotor 341b. The processing surface of the substrate W faces the flash lamps 321.

[0080] During drying, similarly to the above, the substrate W rotated by the hollow motor 341 is heated by emitting light from the flash lamps 321 and the halogen lamps 322. By heating one side and the other side of the substrate W in this manner, the difference in stress applied to both sides can be reduced, and therefore it is possible to prevent the substrate W from thermally expanding and being subjected to excessive stress, which can cause cracks or the like.

[0081] (2) The temperature maintaining unit is not limited to halogen lamp 322. It may be an infrared lamp. If the heating speed of the temperature maintaining unit is slow, heating may start before the flash lamp 321 emits light. Also, if the heating speed of the temperature maintaining unit is fast, heating may start after the flash lamp 321 emits light. If it is possible to maintain the temperature by residual heat, the light emission of the lamp used as the temperature maintaining unit may be stopped together with the light emission of the flash lamp 321.

[0082] (3) As long as the processing in the processing device 110 is a process that ultimately requires cleaning and drying, the type of processing and the processing liquid are not limited to those exemplified above. The substrate W to be processed and the processing liquid are also not limited to those exemplified above. The cleaning liquid L that is piled on the substrate W after cleaning in the cleaning device 120 is not limited to IPA. For example, the liquid may be piled with DIW.

[0083] [Other embodiments] Although the embodiment of the present invention and the modified examples of each part have been described above, these embodiments and the modified 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 modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims. [Explanation of symbols]

[0084] 1. Substrate Processing Equipment 1a Chamber 1b Cassette 1c Transport robot 1d Buffer Unit 11 Cleaning Room 11a opening 11b Door 12 Support part 13 Rotation mechanism 14 cups 15 Supply section 15a Nozzle 15b Moving mechanism 20 Handling Equipment 21 Robot Hand 22 Moving mechanism 31 Drying room 31a aperture 31b Door 31c inlet 31d Exhaust port 31e Air supply section 31f Exhaust section 32 Heating section 32a Partition window 33 Window 34 Support part 34a Rotating table 34b Retaining member 34c Rotation axis 35 Drive mechanism 35a Rotating part 35b Lifting section 36 cups 37 Measuring part 37a Detector 37b Swing arm 37c Swing mechanism 38 Supply section 38a Nozzle 38b Swing arm 38c Oscillating mechanism 41 Mechanical control unit 42 Film thickness analysis section 43 Heating control section 110 Processing equipment 120 Cleaning Equipment 200 Transport device 300 Drying equipment 321 Flash Lamp 322 Halogen lamp 322a support stand 341 Hollow Motor 341a Stator 341b Rotor 400 Control device

Claims

1. a drying chamber into which a substrate having a liquid film formed on a treatment surface thereof is carried; a support section that supports the substrate carried into the drying chamber; a flash lamp provided in the drying chamber for heating a surface layer of the substrate to be treated to a temperature equal to or higher than a temperature at which an air layer due to the Leidenfrost phenomenon occurs between the liquid film and the surface layer; a temperature maintaining unit that maintains the temperature of the surface layer by heating so as to maintain the gas layer by heating of the flash lamp; a driving mechanism for rotating the substrate together with the support portion to discharge the liquid film, in which the gas layer is generated between the liquid film and the surface layer, by centrifugal force generated by the rotation of the substrate; A substrate drying apparatus comprising:

2. 2. The substrate drying apparatus according to claim 1, wherein the temperature maintaining unit starts heating before or simultaneously with the flash lamps emitting light.

3. 2. The substrate drying apparatus according to claim 1, wherein the temperature maintaining unit continues heating even after the flash lamp is turned off.

4. 2. The substrate processing apparatus according to claim 1, wherein the flash lamp and the temperature maintaining unit are disposed on opposite sides of the substrate.

5. a processing device that processes the substrate by supplying a processing liquid while rotating the substrate; a cleaning device that cleans the processed substrate by supplying a processing liquid while rotating the substrate; An apparatus for drying a substrate according to any one of claims 1 to 4, a transport device that transports the substrate cleaned in the cleaning device with a liquid film formed thereon by the processing liquid thereon into the substrate drying device; A substrate processing apparatus comprising:

6. the support section supports the substrate that has been carried into the drying chamber in a state in which a liquid film of the processing liquid has been formed on the processing surface; a drive mechanism for rotating the substrate together with the support; a flash lamp heats a surface layer of the processing surface of the substrate to a temperature equal to or higher than a temperature at which an air layer due to the Leidenfrost phenomenon occurs between the liquid film and the surface layer; a temperature maintaining unit that maintains the temperature of the surface layer by heating so as to maintain the gas layer by heating of the flash lamp; The liquid film is discharged by centrifugal force generated by rotation of the substrate. A method for drying a substrate.

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