Substrate drying apparatus, substrate processing apparatus, 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 Art]

[0002] In a manufacturing process for producing semiconductors, liquid crystal panels, and the like, a substrate processing apparatus is used which supplies a processing liquid 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 cleans and dries the surface to be processed after the processing. In the drying step of this substrate processing apparatus, fine uneven patterns such as those in memory cells or around gates may collapse and become blocked, due to factors including the spacing and structure between patterns formed on the surface layer of the surface to be processed, and the surface tension of the processing liquid. This tendency increases with the recent miniaturization accompanying the high integration and high capacity of semiconductors.

[0003] In order to suppress pattern collapse, a substrate drying method using IPA (2-propanol: isopropyl alcohol), which has a lower surface tension than ultrapure water, has been proposed. In this substrate drying method, DIW (ultrapure water) on the substrate surface is replaced with a mixed solution of IPA and DIW, and then the substrate is dried. However, the miniaturization of semiconductors is progressing more and more, and even when drying is performed using a highly volatile organic solvent such as IPA, patterns on a wafer may collapse due to the surface tension of the liquid or other factors.

[0004] For example, in the process of liquid drying, if non-uniformity occurs in the drying rate on the substrate surface and liquid remains between some patterns, the patterns will collapse due to the surface tension of the liquid in that portion. More specifically, patterns in the region where liquid remains collapse due to elastic deformation caused by the surface tension of the liquid, and residues slightly dissolved in the liquid aggregate. Then, when the liquid completely vaporizes, the collapsed patterns adhere to each other.

[0005] To address this, a drying method has been proposed in which, after supplying cleaning fluid, the surface layer of the surface to be treated on a rotating substrate is rapidly heated to a temperature at which the Leidenfrost phenomenon occurs, creating a gas layer between the surface layer and the liquid film of the cleaning fluid. This causes the liquid film to form droplets, which are then discharged from the substrate by the centrifugal force of rotation, thereby suppressing the collapse of fine patterns due to surface tension (see Patent Document 1). In this drying method, a nucleated boiling state in which minute bubbles are generated inside the liquid film that is in direct contact with the heated surface is insufficient. It is necessary to create a film boiling state in which a vapor film is interposed between the liquid and the heated surface, and heat is transferred from the heated surface through the vapor film, causing evaporation in the vapor film. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Patent No. 6400919 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] As described above, even in drying methods that utilize the Leidenfrost effect to remove liquid films by forming droplets, areas of pattern blockage may occur on the substrate. This is thought to be because some of the liquid film in contact with the surface layer of the substrate remains in a nucleated boiling state rather than a film boiling state, preventing the liquid film from forming droplets and causing it to remain between the irregularities of the pattern. Ultimately, surface tension acts on these areas, resulting in pattern blockage.

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

[0009] Traditional heating sources used in the semiconductor field include flash lamps and halogen lamps. However, while flash lamps can instantly heat the surface of a substrate in a few milliseconds, they cannot maintain the temperature necessary for the film to boil until the liquid droplets are discharged from the substrate. On the other hand, halogen lamps take several seconds to heat the surface of the substrate, so their heating speed is slower than flash lamps, but once the substrate reaches the film boiling point, it can maintain that temperature. However, to more stably form liquid droplets, the rate at which halogen lamps heat up to the film boiling point needs to be increased to a few milliseconds, which requires enormous power output. In other words, a power supply capable of producing a large output would be necessary, and repeated heating would result in excessive power consumption, making it impractical.

[0010] The 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 across the entire surface layer of the substrate. [Means for solving the problem]

[0011] The substrate drying apparatus of the present invention comprises: a drying chamber into which a substrate in which a liquid film of processing liquid has formed on the surface to be processed is brought; a support unit for supporting the substrate brought into the drying chamber; a flash lamp provided in the drying chamber for heating the surface layer of the surface to be processed on the substrate to a temperature above which a gas layer due to the Leidenfrost phenomenon occurs throughout the entire space between the liquid film and the surface layer; a temperature maintenance unit for maintaining the temperature of the surface layer by heating in order to maintain the gas layer caused by the heating of the flash lamp; and a drive mechanism for rotating the substrate together with the support unit, thereby discharging the liquid film, which has a gas layer formed between it and the surface layer, by centrifugal force caused by the rotation of the substrate. Furthermore, the temperature maintenance unit is a halogen lamp or an infrared lamp. . Furthermore, the substrate drying apparatus of the present invention comprises a drying chamber into which a substrate having a liquid film formed on its surface is brought; a support unit for supporting the substrate brought into the drying chamber; a flash lamp provided in the drying chamber for heating the surface layer of the substrate to be treated to a temperature above which a gas layer due to the Leidenfrost phenomenon occurs throughout the space between the liquid film and the surface layer; a temperature maintenance unit for maintaining the temperature of the surface layer by heating in order to maintain the gas layer caused by the heating of the flash lamp; and a drive mechanism for rotating the substrate together with the support unit, thereby discharging the liquid film with which the gas layer has formed between it and the surface layer by centrifugal force caused by the rotation of the substrate, wherein the temperature maintenance unit continues heating even after the flash lamp is turned off. Furthermore, the apparatus includes a drying chamber into which a substrate with a liquid film formed by a processing solution on the surface to be processed is brought; a support section for supporting the substrate brought into the drying chamber; a flash lamp provided in the drying chamber for heating the surface layer of the surface to be processed on the substrate to a temperature above which a gas layer due to the Leidenfrost phenomenon occurs throughout the entire space between the liquid film and the surface layer; a temperature maintenance section for maintaining the temperature of the surface layer by heating in order to maintain the gas layer caused by the heating of the flash lamp; and a drive mechanism for rotating the substrate together with the support section, thereby discharging the liquid film with the gas layer formed between it and the surface layer by centrifugal force caused by the rotation of the substrate, wherein the flash lamp and the temperature maintenance section are arranged on opposite sides of the substrate.

[0012] The substrate processing apparatus of the present invention comprises a processing apparatus that processes a substrate by supplying a processing liquid while rotating the substrate, a cleaning apparatus that cleans the processed substrate by supplying a processing liquid while rotating the substrate, a substrate drying apparatus, and a conveying apparatus that carries out the substrate cleaned in the cleaning apparatus with a liquid film formed by the cleaning liquid and carries it into the substrate drying apparatus.

[0013] The substrate drying method of the present invention includes a support unit that supports a substrate that has been brought into a drying chamber with a liquid film formed on the surface to be processed by a processing liquid, a drive mechanism that rotates the substrate together with the support unit, and a flash lamp that heats the surface layer of the surface to be processed on the substrate to a temperature above which a gas layer due to the Leidenfrost effect occurs throughout the entire space between the liquid film and the surface layer. It is a halogen lamp or an infrared lamp. The temperature maintenance unit maintains the temperature of the surface layer by heating so as to maintain the gas layer heated by the flash lamp, and discharges the liquid film by centrifugal force caused by the rotation of the substrate. [Effects 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 across the entire surface layer of the substrate. [Brief explanation of the drawing]

[0015] [Figure 1] This is a simplified configuration diagram showing a substrate processing apparatus according to an embodiment. [Figure 2] Figure 1 is a configuration diagram showing the cleaning and drying apparatus of the substrate processing apparatus. [Figure 3] This is an internal diagram showing the drying apparatus during substrate loading (A) and film thickness measurement (B). [Figure 4] This is an internal configuration diagram showing the drying apparatus when cleaning solution is being supplied (A) and when the substrate is in standby mode (B). [Figure 5] This is an internal diagram showing the drying apparatus during substrate drying (A) and substrate lowering (B). [Figure 6] This flowchart shows the procedure for the substrate drying process in the embodiment. [Figure 7] It is an explanatory diagram showing the flow of a drying process using the Leidenfrost phenomenon. [Figure 8] It is an explanatory diagram showing a liquid film remaining in a pattern. [Figure 9] It is a graph showing temperature changes of a flash lamp, a halogen lamp, and a substrate. [Figure 10] It is a configuration diagram showing a modified example of a temperature maintaining unit.

Mode for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings. [Summary] As shown in FIG. 1, the substrate processing apparatus 1 of the present embodiment includes a plurality of chambers 1a that accommodate apparatuses for performing various processes, and is a single-wafer processing apparatus that processes substrates W, which have been accommodated in a cassette (FOUP) 1b and conveyed in a previous step, one by one in each chamber 1a. Unprocessed substrates W are taken out one by one from the 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 apparatuses described below.

[0017] The substrate processing apparatus 1 includes a processing apparatus 110, a cleaning apparatus 120, a transfer apparatus 200, a drying apparatus 300, and a control apparatus 400. The processing apparatus 110 is an etching apparatus that removes unnecessary films and leaves circuit patterns by supplying a processing liquid (for example, an aqueous phosphoric acid solution, a mixed solution of hydrofluoric acid and nitric acid, a mixed solution of acetic acid, sulfuric acid and hydrogen peroxide water (SPM: Sulfuric hydrogen Peroxide Mixture), etc.) to a rotating substrate W, for example. The cleaning apparatus 120 cleans the substrate W etched by 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 processed in the processing device 110 to the cleaning device 120, and the substrate W cleaned in the cleaning device 120 to the drying device 300. The drying device (substrate drying device) 300 performs drying by heating the substrate W, which has been cleaned with cleaning solution, while rotating it. The control device 400 controls each of the above devices.

[0019] The substrate W processed in this embodiment is, for example, a semiconductor wafer. Hereinafter, the surface of the substrate W on which patterns, etc., are formed will be referred to as the surface to be processed. Furthermore, on the surface to be processed of the substrate, the outermost surface of the pattern that is in contact with the liquid film formed by the processing solution will be referred to as the surface layer.

[0020] For the cleaning process, alkaline cleaning solution (APM), ultrapure water (DIW), and volatile solvent (IPA) are used as cleaning solutions. APM is a chemical solution made by mixing ammonia water and hydrogen peroxide water, and is used to remove residual organic matter. DIW is used to wash away any APM remaining on the treated surface of the substrate W after APM treatment. IPA has a lower surface tension and higher volatility than DIW, so it is used to replace DIW and reduce pattern collapse due to surface tension.

[0021] [Washing equipment] As shown in Figure 2, the cleaning device 120 includes a cleaning chamber 11 which is a container for performing cleaning processing inside, a support part 12 which supports the substrate W, a rotating mechanism 13 which rotates the support part 12, a cup 14 which receives the splashed cleaning liquid L from around the substrate W, and a supply part 15 which supplies the cleaning liquid L. The supply part 15 is equipped with a nozzle 15a which drops the cleaning liquid L and a moving mechanism 15b which moves the nozzle 15a.

[0022] The cleaning process is performed by supplying cleaning solution L from a nozzle 15a to the surface of the substrate W to be processed, which is supported by a support section 12 and rotated by a rotation mechanism 13. The cleaning process involves supplying APM to the surface of the substrate W that has been etched by the processing apparatus 110 to perform APM cleaning, and then performing a pure water rinse with DIW after the APM cleaning to wash away any APM remaining on the surface of the substrate W with pure water. As a result, the surface of the substrate W is coated with the cleaning solution L of DIW. Furthermore, the DIW is finally replaced with IPA. 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.

[0023] [Conveying equipment] The transport device 200 has a handling device 20. The handling device 20 has a robot hand 21 for gripping 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 after etching is unloaded from the processing device 110 and, with a liquid film of cleaning solution L formed on the surface of the substrate W, is unloaded into the cleaning device 120.

[0024] Furthermore, the moving mechanism 22 moves the handling device 20 and the robot hand 21 to remove the cleaned substrate W from the cleaning device 120, and transports the substrate W to the drying device 300 with a liquid film of cleaning solution L formed on the surface of the substrate W. The reason for transporting the substrate W with a liquid film of cleaning solution L formed on the surface of the substrate W is to prevent particles from adhering to the surface of the substrate W during transport.

[0025] [Drying equipment] figure 2As shown, the drying apparatus 300 includes a drying chamber 31, a heating section 32, a window section 33, a support section 34, a drive mechanism 35, a cup 36, a measuring section 37, and a supply section 38. The drying chamber 31 is a container for drying the substrate W inside. The substrate W, with a liquid film formed on its surface by the processing solution, is brought into the drying chamber 31. The drying chamber 31 is box-shaped, for example, a rectangular parallelepiped or a cube. The inner wall of the drying chamber 31 is coated with silica to enhance dust resistance. The drying chamber 31 is provided with an opening 31a for loading and unloading the substrate W. The opening 31a is provided to be openable and closable by a door 31b.

[0026] Furthermore, the drying chamber 31 is provided with an inlet 31c and an exhaust port 31d. The inlet 31c is connected to an air supply section 31e, which includes piping, an intake valve, and an air supply device that supplies clean gas (such as N2). The exhaust port 31d is connected to an exhaust section 31f, which includes piping, an exhaust valve, and an exhaust device that exhausts gas. By supplying clean gas into the drying chamber 31 from the inlet 31c, a clean atmosphere can be created inside the drying chamber 31. In addition, by supplying gas into the drying chamber 31 from the inlet 31c and exhausting the gas inside the drying chamber 31 from the exhaust port 31d, a gas flow is created inside the drying chamber 31. As a result, the vapor of the processing liquid generated when heating the substrate W can be discharged from the drying chamber 31 without filling it. The exhaust section 31f may be provided with a rapid exhaust valve that reduces the pressure caused by the rapidly expanding atmosphere due to the flash of light emitted from the flash lamp 321, which will be described later.

[0027] The heating unit 32 is a device for heating the substrate W. The heating unit 32 is located in the upper part of the drying chamber 31. The heating unit 32 has a flash lamp 321 and a halogen lamp 322. A partition window 32a, which is a plate-shaped material such as quartz, is provided between the flash lamp 321 and the halogen lamp 322. The flash lamp 321 is a straight tube type, and multiple lamps are arranged in parallel horizontally. A power supply and a capacitor (not shown) are connected to the flash lamp 321, and the energy stored in the capacitor allows it to emit light instantaneously and heat to a high temperature. In this embodiment, the flash lamp 321 heats the surface layer of the substrate W to a temperature above which a gas layer due to the Leidenfrost phenomenon occurs throughout the entire space between the liquid film and the surface layer (hereinafter referred to as the Leidenfrost temperature). The Leidenfrost temperature is a temperature range with a different width depending on the type and thickness of the liquid film.

[0028] The halogen lamp 322 is a temperature-maintaining unit that maintains the surface temperature by heating, in order to maintain the vapor layer caused by the heating of the flash lamp 321. The halogen lamp 322 is a straight tube type, and multiple lamps are arranged horizontally above the flash lamp 321, perpendicular to the flash lamp 321. A power supply (not shown) is connected to the halogen lamp 322. Both the flash lamp 321 and the halogen lamp 322 can use a general factory power supply of 200V or less.

[0029] Since the directions of the flash lamp 321 and the halogen lamp 322 are perpendicular, the overall structure is a grid. The flash lamp 321 and the halogen lamp 322 use electromagnetic waves (infrared rays) of a wavelength that heats the surface layer of the substrate W more easily than the cleaning solution 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 over 200°C within a few milliseconds. This causes the liquid film to boil, instantly and uniformly vaporizing the portion of the liquid film in contact with the substrate W, creating a vapor layer that allows the liquid film to float. Since the flash lamp 321 cannot be lit for an extended period, the surface of the substrate W is heated by the halogen lamp 322 to continuously vaporize the floating liquid near the substrate W, preventing re-adhesion to the surface of the substrate W and allowing the liquid film to be removed without influencing surface tension.

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

[0032] The support unit 34 supports the substrate W that has been brought into the drying chamber 31. The support unit 34 has a rotary table 34a, a plurality of holding members 34b, and a rotating shaft 34c. The rotary table 34a is cylindrical in shape with a larger diameter than the substrate W, and its upper surface is a flat circle. The plurality of holding members 34b are arranged at equal intervals along the outer circumference of the substrate W, and hold the substrate W in a horizontal position with a gap between the substrate W and the upper surface of the rotary table 34a. The plurality of holding members 34b are provided 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 and closing mechanism (not shown). The rotating shaft 34c supports the rotary table 34a from below and is a vertical axis that serves as the center of rotation.

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

[0034] In this embodiment, a standby position D and a drying position U are set as the positions of the support portion 34 that change with the drive mechanism 35. The standby position D is the position where the substrate W, which has been brought into the drying chamber 31 with a liquid film formed by the cleaning solution L, is received at a distance from the heating unit 32.

[0035] More specifically, the standby position D is lower than the detection unit 37a and nozzle 38a, which will be described later. The reason for receiving and supporting the substrate W at a position away from the heating unit 32 is as follows: Even if the heating unit 32 heats (lights the lamp) only during the drying process, the window section 33 accumulates heat due to the heat emitted by the heating unit 32. In particular, the window section 33 is located directly below where the heating unit 32 is installed, and because the material is quartz, it has poor thermal conductivity, making it even more prone to accumulating heat. Therefore, repeated drying processes cause heat accumulation in the window section 33 to progress.

[0036] When a substrate W with a liquid film of cleaning solution L formed on it is brought in under these conditions, the radiant heat from the heat-retaining window section 33 causes the liquid film on the substrate W to begin evaporating. However, the entire liquid film does not evaporate instantly; instead, a non-uniform drying state occurs where only a portion evaporates, and the surface tension of the remaining cleaning solution L causes pattern blockage. Therefore, it is necessary to support the substrate at a position away from the heating section 32 to prevent it from being affected by such radiant heat.

[0037] Therefore, the standby position D is a position away from the window portion 33 until the processing liquid (the processing liquid at the time it is brought into the drying chamber 31) that has been repeatedly heated by the heating unit 32 and stored heat in the window portion 33 is no longer at risk of evaporation (the effect of heat is minimal). The drying position U is a position close to the heating unit 32, where the substrate W heated by the heating unit 32 creates a gas layer between itself and the liquid film. In this embodiment, the standby 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 portion 34 from all sides (see Figure 2). The upper part of the peripheral wall of the cup 36 is inclined radially inward and has an opening so as to expose the substrate W on the support portion 34. The cup 36 receives the cleaning liquid L scattered from the rotating substrate W and directs it downward. An outlet (not shown) is formed on the bottom surface of the cup 36 for discharging the flowing cleaning liquid L. The cup 36 is connected to the drive mechanism 35 and is provided to be able to move up and down together with the support portion 34.

[0039] The measuring unit 37 is brought into the drying chamber 31 and measures the thickness of the liquid film on the substrate W in the standby position D. The measuring unit 37 has a detection unit 37a, a swinging arm 37b, and a swinging mechanism 37c. For the detection unit 37a, for example, a laser displacement meter or a camera is used. The swinging arm 37b has a detection unit 37a at its tip and moves the detection unit 37a between a measurement position where it faces the center of the surface to be processed on the substrate W on the support unit 34, and a standby position where it is retracted from the measurement position to allow the substrate W to be loaded and unloaded. The swinging mechanism 37c is a mechanism that swings the swinging arm 37b.

[0040] For example, the optical interference principle can be used as the film thickness measurement method by the measurement unit 37. Alternatively, a weighing scale can be used within the support unit 34. When using this 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 theoretically or experimentally converted to the thickness of the liquid film.

[0041] The supply unit 38 is brought into the drying chamber 31 and supplies cleaning liquid L onto the substrate W 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 cleaning liquid L towards the center of the surface of the substrate W to be processed. Cleaning liquid L is supplied to the nozzle 38a from a storage unit outside the drying chamber 31 via piping (not 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 ultimately applied to the substrate W during the rinsing process after alkaline cleaning in the cleaning device 120. In other words, if the rinsing process is completed with DIW, the substrate is transported from the cleaning device 120 to the drying device 300 with DIW applied to it. In the case of DIW, the supply unit 38 supplies DIW. If DIW is ultimately replaced with IPA, the substrate is transported from the cleaning device 120 to the drying device 300 with IPA applied to it. In the case of IPA, the supply unit 38 supplies new IPA because it may volatilize during transport or absorb moisture from the atmosphere during transport.

[0043] The oscillating arm 38b is equipped with a nozzle 38a at its tip, and moves the nozzle 38a between a supply position facing the center of the surface to be processed on the substrate W on the support part 34, and a retracted position that moves away from the supply position to enable loading and unloading of the substrate W. The oscillating mechanism 38c is a mechanism that oscillates the oscillating arm 38b. The drying position U is located above the supply part 38, which is in the supply position for supplying cleaning liquid L 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 programs, a memory that stores various information such as programs and operating conditions, and drive circuits that drive each element. In other words, 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 also has an input device for inputting information and a display device for displaying information.

[0045] The control device 400 includes 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, rotation start, and rotation stop timing of the support unit 34 by controlling the rotating part 35a of the drive mechanism 35. The mechanism control unit 41 also controls the distance (gap) between the heating unit 32 and the support unit 34 by controlling the lifting part 35b of the drive mechanism 35.

[0046] More specifically, the control device 400 holds the substrate W in the support unit 34 at the standby position D, adjusts the film thickness of the cleaning solution L applied to the surface of the substrate W to be processed, rotates the substrate W and raises it to the drying position U, lights the flash lamp 321 and halogen lamp 322 and dries it for a predetermined time. After that, while maintaining the rotation of the substrate W, it lowers it back to the standby position D. It also controls the oscillation of the nozzle 38a and the discharge of the cleaning solution L, as well as the oscillation and measurement of the detection unit 37a.

[0047] The film thickness analysis unit 42 analyzes the thickness of the liquid film of the cleaning solution L measured by the measurement unit 37. The film thickness analysis unit 42 determines whether the thickness of the liquid film of the cleaning solution L (liquid film thickness value) measured by the measurement unit 37 is within a predetermined threshold range. If the film thickness analysis unit 42 determines that the measured liquid film thickness is within the predetermined threshold range, it determines that the liquid film thickness is appropriate and transmits a permission signal to the mechanism control unit 41 to allow the rotation and raising of the substrate W. Upon receiving the permission signal, the mechanism control unit 41 transmits a signal to the drive mechanism 35 to command the support unit 34 to rotate and raise.

[0048] Appropriate film thicknesses are, for example, 10 μm or less for DIW and 100 μm or less for IPA. These film thicknesses are such that the liquid does not evaporate from the substrate W when it approaches the heating section 32 (approaching the window section 33), and that the liquid thickness allows for good drying during the Leidenfrost drying process. However, these values ​​are examples, and in practice, the appropriate liquid thickness can be determined in advance through experiments, etc. Also, the rotation speed of the substrate W is, for example, around 200 to 300 rpm, and even if the liquid film is adjusted, the liquid film thickness can be maintained at the predetermined thickness within this range of rotation speeds.

[0049] The heating control unit 43 controls the heating unit 32 in accordance with the commands from the mechanism control unit 41. When the support 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 surface of the substrate W on the support unit 34 that is to be processed.

[0050] The heating control unit 43 simultaneously illuminates the flash lamp 321 and the halogen lamp 322. The light emitted by the flash lamp 321 rapidly heats the entire area between the liquid film and the surface layer of the substrate W to be processed, to a temperature above the Leidenfrost temperature. For example, by heating to a temperature of 200°C or higher, the entire surface layer of the substrate W is heated to a temperature above the boiling point of the liquid film within a few milliseconds. Note that the halogen lamp 322 may illuminate before the flash lamp 321. In other words, the temperature maintenance unit may start heating before the flash lamp 321 illuminates.

[0051] As the temperature of the continuously emitting halogen lamp 322 rises, the surface layer of the substrate W is maintained above the Leidenfrost temperature, and the film boiling state is maintained. As a result, the cleaning liquid L on the surface layer of the substrate W to be treated forms into droplets.

[0052] If the film thickness analysis unit 42 determines that the measured thickness of the cleaning solution L film is thinner than the lower limit of a predetermined threshold range, the mechanism control unit 41 outputs a supply instruction to the supply unit 38 to supply processing liquid (cleaning solution L) because the liquid film is too thin. As a result, a predetermined amount (for a predetermined time) of cleaning solution L is supplied from the nozzle 38a to the surface of the substrate W to be processed, bringing the thickness of the liquid film within the predetermined threshold range. After that, drying is performed by rotating and raising the substrate W as described above. The substrate W may be stopped without rotating when replenishing the cleaning solution L, or it may be rotated.

[0053] If the film thickness analysis unit 42 determines that the measured thickness of the cleaning solution L film is thicker than the upper limit of a predetermined threshold range, the mechanism control unit 41 outputs a rotation instruction to the drive mechanism 35 for the support unit 34, indicating that the liquid film is too thick. This causes the cleaning solution L on the substrate W, which rotates with the support unit 34, to be scattered by centrifugal force, bringing the liquid film thickness within the predetermined threshold range. After that, drying is performed by rotating and raising the substrate W as described above.

[0054] [Operation] The operation of the substrate processing apparatus 1 of this embodiment will be explained with reference to the explanatory diagrams in Figures 3 to 5, the flowchart in Figure 6, and the explanatory diagram in Figure 7, in addition to Figures 1 and 2 described above. Note that a substrate manufacturing method for producing a substrate W, a substrate drying method for drying the substrate W, and a substrate processing method for processing the substrate W are also embodiments of this embodiment. Furthermore, the cup 36 is not shown in Figures 3 to 5.

[0055] As shown in Figure 2, the substrate W after etching in the processing apparatus 110 is transported to the cleaning apparatus 120 by the transport apparatus 200. In the cleaning apparatus 120, the support unit 12 holding the substrate W rotates while the supply unit 15 supplies APM to the surface of the substrate W to perform alkaline cleaning, followed by pure water cleaning by supplying DIW. After the pure water cleaning is completed, IPA is supplied to the surface of the substrate W to perform cleaning.

[0056] As a result, the centrifugal force generated by the rotation of the substrate W causes the IPA to spread across the entire surface of the substrate W to be treated, and an alcohol rinsing treatment is performed in which the DIW applied to the surface of the substrate W is replaced by IPA. In this process, since the DIW is replaced by IPA, which has a lower surface tension than DIW, the surface tension acting between the patterns formed on the surface of the substrate W is reduced.

[0057] The transport device 200 unloads the washed substrate W from the washing device 120 and loads it into the drying device 300. It should be noted that, after the pure water washing is complete, it is not always necessary to replace the treated surface of the substrate W, which is coated with DIW, with IPA. In other words, the washing process may be completed with pure water washing using DIW alone.

[0058] As shown in Figure 3(A), with a liquid film (IPA) formed on the surface to be processed by the cleaning solution L, the substrate W is brought in through the opening 31a of the drying chamber 31 of the drying apparatus 300 and held by the holding member 34b of the support part 34 in the standby position D (step S01). As shown in Figure 3(B), the detection part 37a of the measurement part 37 measures the film thickness on the substrate W (step S02).

[0059] If the film thickness is thin (less than the predetermined range in step S03), the supply unit 38 adjusts the film thickness by supplying more cleaning liquid L to the liquid film on the substrate W, as shown in Figure 4(A) (step S04). If the film thickness is thick (greater than the predetermined range in step S03), the support unit 34 rotates, thereby adjusting the film thickness by splashing the cleaning liquid L from the rotating substrate W (step S05).

[0060] If the film thickness is appropriate or becomes appropriate after adjustment (within the predetermined range in step S03), as shown in Figure 4(B), the support part 34 rotates the substrate W (step S06) and rises to the drying position U as shown in Figure 5(A), thereby bringing 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 solution L on the surface of the substrate W is rotated together with the substrate W, so that even after it is heated by the heating part 32 and a gas layer is created between the surface of the substrate W and the cleaning solution L, the liquid film of the cleaning solution L continues to rotate due to inertia, and centrifugal force acts on it.

[0061] The flash lamp 321 and halogen lamp 322 of the heating unit 32 emit light simultaneously to heat the surface of the substrate W (step S08). At this time, the flash lamp 321 emits light for several milliseconds, rapidly heating the entire surface of the substrate W to above the Leidenfrost temperature, and the Leidenfrost phenomenon causes the liquid film to float away from the surface through the gas layer generated at the interface between the surface of the substrate W and the liquid film. The halogen lamp 322 continues to emit light for several seconds before turning off, so that the entire surface of the substrate W remains heated above the Leidenfrost temperature even after the flash lamp 321 has turned off.

[0062] As a result, the liquid film remains suspended from the entire surface of the substrate W, forming droplets, and the cleaning liquid L is blown away by centrifugal force and dried (step S09). In other words, as shown in Figure 7(A), the cleaning liquid L in contact with the pattern P on the surface of the substrate W is heated instantaneously only on the substrate W by the lighting of the flash lamp 321, as shown in Figure 7(B). Because the interface between the surface of the substrate W and the cleaning liquid L begins to vaporize faster than the cleaning liquid L in other parts, a layer of vaporized liquid (cleaning liquid L), i.e., a gas layer G, is generated around the pattern P. Then, because the lighting of the halogen lamp 322 is maintained, the temperature of the surface of the substrate W is maintained, and the gas layer G is maintained. In Figures 7(B), (C), and (D), fine diagonal hatching is applied to the pattern P on the substrate W to show that the substrate W is rapidly heated and that this heating is maintained.

[0063] As shown in Figure 7(C), the liquid (cleaning liquid L) between adjacent patterns P is instantly lifted away from the pattern P by the gas layer G, and immediately forms into droplets due to the Leidenfrost effect, as shown in Figure 7(D). As indicated by the black arrows in the figure, centrifugal force is applied to the cleaning liquid L due to rotation, and each generated droplet is ejected from the substrate W by centrifugal force, so the treated surface of the substrate W dries out, as shown in Figure 7(E).

[0064] In this way, the cleaning liquid L present between the patterns P is lifted away from the gaps between the patterns P across the entire surface of the substrate W being treated, preventing re-adhesion. This suppresses the residue of cleaning liquid L between some of the patterns P, resulting in a uniform drying rate of the liquid on the surface of the substrate W. Consequently, the collapse of the patterns P due to collapsing forces (e.g., surface tension) caused by residual liquid can be suppressed.

[0065] Furthermore, if the liquid film thickness is insufficient and the liquid film dries out by normal drying before the Leidenfrost phenomenon occurs, as shown in Figure 8, pattern collapse will occur due to the surface tension acting on the cleaning liquid L remaining between some of the patterns P. In this embodiment, since the liquid film thickness of the cleaning liquid L on the treated surface of the substrate W is adjusted to an appropriate thickness, the liquid film is maintained while the Leidenfrost phenomenon is occurring, and the liquid film that floats up due to the gas layer is removed from between the patterns P by centrifugal force, thus preventing pattern collapse due to surface tension.

[0066] Subsequently, as shown in Figure 5(B), the support unit 34 descends to the standby position D while maintaining the rotation of the substrate W (step S10). After the support unit 34 stops the rotation of the substrate W (step S11), the transport device 200 discharges the substrate W through 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 formed by a processing liquid on the surface to be processed is brought; a support section 34 for supporting the substrate W brought into the drying chamber 31; a flash lamp 321 provided in the drying chamber 31 for heating the surface layer of the surface to be processed on the substrate W to a temperature above which a gas layer due to the Leidenfrost phenomenon occurs throughout the space between the liquid film and the surface layer; a temperature maintenance section (halogen lamp 322) for maintaining the temperature of the surface layer by heating in order to maintain the gas layer caused by the heating of the flash lamp 321; and a drive mechanism 35 for rotating the substrate W together with the support section 34, thereby discharging the liquid film with which a gas layer has formed between it and the surface layer by centrifugal force caused 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, 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 and transports it to a drying apparatus 300.

[0069] In this embodiment of the substrate drying method, the support unit 34 supports the substrate W that has been brought into the drying chamber 31 with a liquid film formed on the surface to be processed by the processing liquid, the drive mechanism 35 rotates the substrate W together with the support unit 34, the flash lamp 321 instantaneously heats the surface layer of the surface to be processed on the substrate W to a temperature above which a gas layer due to the Leidenfrost effect will occur throughout the entire space between the liquid film and the surface layer, the temperature maintenance unit (halogen lamp 322) maintains the temperature of the surface layer by heating to maintain the gas layer caused by the heating of the flash lamp 321, and the liquid film is discharged by centrifugal force due to the rotation of the substrate W.

[0070] Thus, the flash lamp 321, which can only emit light for a short time but can instantly heat to a high temperature, heats the surface of the substrate W to above the Leidenfrost temperature, causing the liquid film to float. The temperature maintenance unit (halogen lamp 322) then maintains the Leidenfrost temperature. As a result, the liquid film that has floated up due to the gas layer does not reattach to the surface and can be removed from the substrate W, preventing pattern collapse due to residual liquid. Furthermore, compared to bringing the film to a boiling state using only the halogen lamp 322, it is possible to stably bring the liquid film to a boiling state and form liquid droplets without using an enormous amount of electricity.

[0071] Figure 9 schematically shows the temperature changes of the flash lamp 321, halogen lamp 322, and substrate W in a graph with time on the horizontal axis and temperature on the vertical axis. When heating with only the flash lamp 321, as shown by the dashed line in the figure, the surface layer of the substrate can be instantly heated to above the Leidenfrost temperature (two-dot chain line in the figure), but the temperature of the film boiling state cannot be maintained until the liquid droplets are discharged. On the other hand, when heating with only the halogen lamp 322, as shown by the one-dot chain line in the figure, it takes longer to raise the temperature than with the flash lamp 321, so the entire surface layer cannot be instantly heated to above the Leidenfrost temperature, and re-adhesion of liquid droplets to the surface layer occurs.

[0072] In this embodiment, even after the flash lamp 321 is turned off, the halogen lamp 322 continues to heat, allowing the average temperature of the substrate W to be maintained above the Leidenfrost temperature, as shown by the solid line in the figure. In other words, it is possible to instantly bring the liquid film to a film boiling temperature and then maintain that temperature. The instantaneous time, that is, the time until the film boiling state is reached, is preferably 3 msec or less. This allows only the surface layer of the liquid film to reach a film boiling state in a very short time. In this way, the surface layer of the liquid film across the entire surface of the substrate W does not remain in a nucleated boiling state but instantly reaches a film boiling state, making it easier for the liquid film to form droplets. Furthermore, after instantly reaching a film boiling state, that film boiling state can be maintained. More specifically, by raising 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. Therefore, in the figure, after the transition from region α, where the liquid film adheres to the surface, to region β, where the liquid film floats away from the surface due to the Leidenfrost effect, re-adhesion of the liquid film is prevented. Consequently, drying by the Leidenfrost effect can be achieved without causing a temperature drop in the substrate W due to the extinguishing of the flash lamp 321, and without requiring the halogen lamp 322 to reach extremely high temperatures.

[0073] Furthermore, if the flash lamp 321 can heat the substrate W to a temperature of approximately 300°C in less than one second, the liquid film on the surface of the substrate W can immediately enter a film boiling state (without remaining in a nucleation boiling state) via a nucleation boiling state. Also, according to Figure 9, if the maximum heating temperature of the flash lamp 321 is set to approximately 2 to 3 times the Leidenfrost temperature, the liquid film on the surface of the substrate W can enter a film boiling state without remaining in a nucleation boiling state.

[0074] Here, the flash lamp 321 needs to be heated instantaneously to the Leidenfrost temperature, requiring high energy. This condition can be achieved by reducing the pulse width, which allows for instantaneous emission of high energy.

[0075] As shown in Figure 9, the halogen lamp 322 reaches its Leidenfrost temperature in approximately 1 second. In other words, although the average substrate temperature decreases after the flash lamp 321 stops emitting light, the average substrate temperature can be maintained at the Leidenfrost temperature because the halogen lamp 322 reaches the Leidenfrost temperature in approximately 1 second.

[0076] (2) The temperature maintenance 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 maintenance unit is slow, it is possible to heat the unit to a temperature above the Leidenfrost temperature when the flash lamp 321 is turned off.

[0077] (3) The temperature maintenance unit (halogen lamp 322) continues heating even after the flash lamp 321 is turned off. This prevents cooling due to the flash lamp 321 being turned off and maintains the Leidenfrost temperature.

[0078] (modified version) (1) The flash lamp 321 and the temperature maintenance unit may be arranged on opposite sides of the substrate W. For example, as shown in Figure 10, the flash lamp 321 may be installed on the ceiling side of the drying chamber 31, and the halogen lamp 322 may be installed on the floor side, with the substrate W in between. In this embodiment, the halogen lamp 322 is fixedly supported by a support base 322a. An annular hollow motor 341 is installed on the floor of the drying chamber 31. The fixed side of the hollow motor 341 is configured as a stator 341a made of coils, and the rotating side is provided as a rotor 341b made of magnets.

[0079] The rotor 341b is provided with multiple holding members 34b. As a result, the substrate W held by the holding members 34b is positioned spaced apart on the support base 322a and rotates with the rotation of the rotor 341b. The surface of the substrate W to be processed faces the flash lamp 321.

[0080] During drying, the substrate W is heated by illuminating the flash lamp 321 and halogen lamp 322 while it is rotated by the hollow motor 341, as described above. By heating one side of the substrate W and the other side separately in this way, the difference in stress applied to both sides can be reduced, thereby preventing excessive stress on the substrate W due to thermal expansion and thus preventing cracking and other damage.

[0081] (2) The temperature maintenance unit is not limited to a halogen lamp 322. It may also be an infrared lamp. If the heating rate of the temperature maintenance unit is slow, heating may be started before the flash lamp 321 emits light. If the heating rate of the temperature maintenance unit is fast, heating may be started after the flash lamp 321 emits light. If temperature maintenance is possible by residual heat, the light emission of the lamp used as the temperature maintenance unit may be stopped at the same time as the light emission of the flash lamp 321.

[0082] (3) The processing of the processing apparatus 110 is not limited to the examples given above, as long as it is a process that ultimately requires cleaning and drying. The substrate W to be processed and the processing liquid are also not limited to the examples given above. The cleaning liquid L applied to the substrate W after cleaning in the cleaning apparatus 120 is not limited to IPA. For example, it may be applied using DIW.

[0083] [Other embodiments] Although embodiments and modifications of the present invention have been described above, these embodiments and modifications are presented as examples only 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 spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the invention described in the claims. [Explanation of Symbols]

[0084] 1. Substrate processing device 1a Chamber 1b Cassette 1c Transport robot 1d buffer unit 11 Washing Room 11a opening 11b Door 12 Support part 13 Rotation mechanism 14 cups 15 Supply section 15a Nozzle 15b Moving mechanism 20 Handling devices 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 section 34 Support part 34a Rotary Table 34b Retaining member 34c Rotation axis 35 Drive mechanism 35a Rotating part 35b Lifting section 36 cup 37 Measuring part 37a Detection unit 37b Swivel Arm 37c Oscillating mechanism 38 Supply section 38a Nozzle 38b Swivel Arm 38c Oscillating mechanism 41 Mechanism Control Unit 42 Film Thickness Analysis Section 43 Heating Control Unit 110 Processing Unit 120 Cleaning device 200 Conveyor 300 Drying equipment 321 Flash Lamp 322 Halogen Lamp 322a support stand 341 Hollow Motor 341a Stator 341b Rotor 400 Control Unit

Claims

1. A drying chamber into which a substrate with a liquid film formed by the processing solution on the surface to be processed is brought, A support portion for supporting the substrate that has been brought into the drying chamber, A flash lamp provided in the drying chamber, which heats the surface layer of the substrate to be treated to a temperature above which a gas layer due to the Leidenfrost phenomenon occurs throughout the entire space between the liquid film and the surface layer, A temperature maintenance unit maintains the temperature of the surface layer by heating in order to maintain the gas layer by heating the flash lamp, A drive mechanism that rotates the substrate together with the support portion, thereby discharging the liquid film, which has a gas layer formed between it and the surface layer, by centrifugal force caused by the rotation of the substrate, It has, A substrate drying apparatus characterized in that the temperature maintenance unit is a halogen lamp or an infrared lamp.

2. The substrate drying apparatus according to claim 1, characterized in that the temperature maintenance unit starts heating before or simultaneously with the flash lamp emitting light.

3. A drying chamber into which a substrate in which a liquid film of processing solution has been formed on the surface to be processed is brought; A support portion for supporting the substrate that has been brought into the drying chamber, A flash lamp provided in the drying chamber, which heats the surface layer of the substrate to be treated to a temperature above which a gas layer due to the Leidenfrost phenomenon occurs throughout the entire space between the liquid film and the surface layer, A temperature maintenance unit maintains the temperature of the surface layer by heating in order to maintain the gas layer by heating the flash lamp, A drive mechanism that rotates the substrate together with the support portion, thereby discharging the liquid film, which has a gas layer formed between it and the surface layer, by centrifugal force caused by the rotation of the substrate, It has, The substrate drying apparatus is characterized in that the temperature maintenance unit continues heating even after the flash lamp is turned off.

4. A drying chamber into which a substrate in which a liquid film of processing solution has been formed on the surface to be processed is brought; A support portion for supporting the substrate that has been brought into the drying chamber, A flash lamp provided in the drying chamber, which heats the surface layer of the substrate to be treated to a temperature above which a gas layer due to the Leidenfrost phenomenon occurs throughout the entire space between the liquid film and the surface layer, A temperature maintenance unit maintains the temperature of the surface layer by heating in order to maintain the gas layer by heating the flash lamp, A drive mechanism that rotates the substrate together with the support portion, thereby discharging the liquid film, which has a gas layer formed between it and the surface layer, by centrifugal force caused by the rotation of the substrate, It has, A substrate processing apparatus characterized in that the flash lamp and the temperature maintenance unit are arranged on opposite sides of the substrate.

5. A processing apparatus that processes a substrate by supplying a processing solution while rotating the substrate, A cleaning apparatus that cleans the processed substrate by supplying a processing solution while rotating it, A substrate drying apparatus according to any one of claims 1 to 4, A conveying device that transports the substrate, which has been cleaned in the cleaning device, with a liquid film formed by the processing solution, and transports it to the substrate drying device. A substrate processing apparatus characterized by having

6. The support part supports the substrate that has been brought into the drying chamber with a liquid film formed on the surface to be processed by the processing solution. The drive mechanism rotates the substrate together with the support portion, The flash lamp heats the surface layer of the substrate to be treated to a temperature above which a gas layer due to the Leidenfrost phenomenon occurs throughout the entire space between the liquid film and the surface layer. A temperature maintenance unit, which is a halogen lamp or an infrared lamp, maintains the temperature of the surface layer by heating in order to maintain the gas layer by heating of the flash lamp. The liquid film is discharged by centrifugal force caused by the rotation of the substrate. A substrate drying method characterized by the following features.

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