JP2023048697A - SUBSTRATE DRYING APPARATUS, SUBSTRATE PROCESSING APPARATUS, AND SUBSTRATE DRYING METHOD - Google Patents

Abstract

A substrate drying apparatus, a substrate processing apparatus, and a substrate drying method capable of reducing the occurrence of pattern clogging with a simple configuration are provided. A substrate drying device (300) in a substrate processing apparatus (1) includes a heating section (36), a first volatile solvent supply section (34), and a water repellent agent whose surface tension when vaporized is a first level. A second volatile solvent supply unit 35 for supplying a second volatile solvent smaller than the volatile solvent V, a drying chamber 31 into which the substrate W on which the liquid film is formed is carried, and a driving mechanism for rotating the substrate. Then, the first volatile solvent is supplied from the first volatile solvent supply unit to replace the liquid film with the first volatile solvent, and the second volatile solvent supply unit supplies the second volatile solvent H to replace the first volatile solvent formed on the substrate with the second volatile solvent and form a water-repellent film, and the heating unit heats the substrate to produce the second volatile solvent liquid An air layer is generated between the film and the substrate, and the liquid film of the second volatile solvent is discharged by centrifugal force due to rotation. [Selection drawing] Fig. 2

Description

The present invention relates to a substrate drying apparatus, a substrate processing apparatus, and a substrate drying method.

In the manufacturing process of semiconductors and liquid crystal panels, etc., substrate processing involves supplying a processing liquid to the processing surface of a substrate such as a wafer or liquid crystal substrate, processing the processing surface, and then washing and drying the processing surface after processing. A device is used.

In the drying process of this substrate processing apparatus, patterns such as those around memory cells and gates may collapse and become clogged due to the spacing and structure of the patterns, the surface tension of the processing liquid, and the like. In particular, the aspect ratio, which is the ratio of the depth to the wiring width and opening width, has increased with the recent miniaturization associated with the high integration and high capacity of semiconductors, making pattern collapse more likely to occur. there is

In order to suppress such pattern collapse, a substrate drying method using IPA (2-propanol: isopropyl alcohol) after rinsing with DIW (ultra-pure water) has been proposed. This substrate drying method replaces DIW (ultra-pure water) on the substrate surface with IPA, which has a lower surface tension than DIW, thereby reducing pattern collapse due to surface tension during the drying process.

JP 2008-034779 A

However, the miniaturization of semiconductors is progressing more and more, and even when drying using a highly volatile organic solvent (volatile solvent) such as IPA, the fine pattern of the wafer collapses due to the surface tension of the liquid. There is

For example, when the drying speed of the substrate surface becomes non-uniform during the process of drying the liquid, and if the liquid remains between some patterns, the pattern collapses due to the surface tension of the liquid in that part. Specifically, the patterns of the portion where the liquid remains are collapsed due to elastic deformation due to the surface tension of the liquid, and the residue slightly dissolved in the liquid aggregates. Then, when the liquid is completely vaporized, the fallen patterns adhere to each other and block.

In order to deal with this, in addition to IPA, a water-repellent agent, which is a modifier capable of making the surface of the substrate W water-repellent, is supplied. A water-repellent film is formed by replacing hydroxyl groups on the surface with functional groups. As a result, a water-repellent film is formed also between the patterns, the lyophilicity is lowered, and the contact angle of the liquid is increased. That is, since the surface tension of the liquid on the surface of the substrate is further lowered, the force of attraction between the patterns can be weakened, and collapse of the patterns can be suppressed.

When a water-repellent agent is used, after the water-repellent film is formed by supplying the water-repellent agent, the excess water-repellent agent is removed by rinsing with IPA or the like, followed by drying. However, even after the drying treatment, the water-repellent film formed on the substrate surface remains. Therefore, it is necessary to perform a water-repellent film removal process for removing the water-repellent film on the substrate surface. The removal of the water-repellent film is performed, for example, by plasma treatment such as ashing or UV irradiation treatment.

For this reason, it is necessary to add a removal device such as a plasma processing device or a UV irradiation device to the substrate processing apparatus independently of the drying device, and a transfer process from the drying device to the removal device is required. As a result, the substrate processing apparatus becomes complicated and large, the number of processes increases, and the productivity of substrate processing decreases. Furthermore, when the pattern becomes deeper and the aspect ratio increases, UV irradiation may not be able to remove the water-repellent film to the bottom of the pattern.

An object of the embodiments 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 clogging with a simple configuration.

A substrate drying apparatus according to an embodiment of the present invention includes a heating section for heating a substrate, a first volatile solvent supply section for supplying a first volatile solvent onto a surface to be processed of the substrate, and A second volatile solvent that contains a water repellent agent that forms a water repellent film on the treated surface and that supplies a second volatile solvent that has a lower surface tension than the first volatile solvent when vaporized. The substrate in which the solvent supply unit, the heating unit, the first volatile solvent supply unit, and the second volatile solvent supply unit are accommodated, and a liquid film of the processing liquid is formed on the surface to be processed. a drying chamber into which is carried in; a supporting portion that receives the substrate carried into the drying chamber; a drive mechanism that rotates the substrate supported by the supporting portion; By supplying a first volatile solvent, a liquid film of the processing liquid formed on the surface to be processed of the substrate is replaced with the first volatile solvent, and the second volatile solvent supply unit By supplying the second volatile solvent from the substrate, the first volatile solvent formed on the surface to be processed of the substrate is replaced with the second volatile solvent, and the substrate to be processed is replaced with the second volatile solvent. By forming the water-repellent film on the surface and heating the substrate with the heating unit, an air layer is formed between the liquid film of the second volatile solvent containing the water-repellent agent and the substrate. and a control device for discharging the liquid film of the second volatile solvent by centrifugal force generated by the rotation of the substrate.

A substrate processing apparatus according to an embodiment of the present invention includes a processing apparatus that processes the substrate by supplying a first processing liquid while rotating the substrate, and a substrate that has been processed by the processing apparatus and performs a second processing while rotating the substrate. A cleaning device for cleaning by supplying a liquid, a substrate drying device, and a state in which a liquid film is formed on the substrate cleaned by the cleaning device by the second processing liquid supplied by the cleaning device. and a conveying device for carrying out the substrate at the substrate drying device and carrying it into the substrate drying device.

In the substrate drying method according to the embodiment of the present invention, the first volatile solvent supplied from the first volatile solvent supply unit is rotated by the drive mechanism while the substrate on which the liquid film of the treatment liquid is formed and supported by the support unit is rotated. By supplying the solvent, the liquid film of the treatment liquid is replaced with the first volatile solvent. By supplying a second volatile solvent whose surface tension is lower than that of the first volatile solvent, the liquid film of the first volatile solvent is replaced with the second volatile solvent, and the substrate is repellent. By forming a hydrated film and heating the substrate by a heating unit, an air layer is generated between the liquid film of the second volatile solvent containing the water repellent agent and the substrate. The liquid film of the volatile solvent of 2 is discharged by the centrifugal force caused by the rotation of the substrate.

The embodiments of 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 clogging with a simple configuration.

1 is a simplified configuration diagram showing a substrate processing apparatus according to an embodiment; FIG. 2 is a configuration diagram showing a cleaning device and a drying device of the substrate processing apparatus of FIG. 1; FIG. FIG. 4 is an internal configuration diagram showing the time (A) when the substrate is loaded into the drying device and the time (B) when the first volatile solvent is supplied. It is an internal configuration diagram showing the time of supplying the second water-repellent solvent (A), the time of supplying the first volatile solvent, and the time of film thickness measurement (B) of the drying device. FIG. 4 is an internal configuration diagram showing the substrate drying time of the drying apparatus; 4 is a flow chart showing a procedure of substrate drying processing according to the embodiment; FIG. 4 is an explanatory diagram schematically showing the flow of drying processing using the Leidenfrost phenomenon; FIG. 4 is an explanatory diagram showing a liquid film remaining in a pattern;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[overview]
As shown in FIG. 1, a substrate processing apparatus 1 of the present embodiment includes a plurality of chambers 1a containing apparatuses for performing various types of processing. This is a single-wafer processing apparatus that processes the substrates W one by one in each chamber 1a. The unprocessed substrates W are taken out one by one from the cassette 1b by the transport robot 1c, temporarily placed in the buffer unit 1d, and then transported to each chamber 1a and processed by various devices described below. done.

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 applies, for example, a first processing liquid (for example, a phosphoric acid aqueous solution, a mixed liquid of hydrofluoric acid and nitric acid, a mixed liquid of acetic acid, sulfuric acid, and hydrogen peroxide water (SPM: Sulfuric hydrogen peroxide solution) to the rotating substrate W. Mixture, etc.) to remove unnecessary films and leave a circuit pattern. The cleaning device 120 cleans the substrate W etched by the etching device with a cleaning liquid (second processing liquid). 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 transports the substrate W cleaned in the cleaning device 120 to the drying device 300 . The drying device (substrate drying device) 300 performs a drying process by heating the substrate W cleaned with the cleaning liquid while rotating it. The control device 400 controls each device described above.

The substrate W processed according to this embodiment is, for example, a semiconductor wafer. Hereinafter, the surface of the substrate W on which a pattern or the like is formed will be referred to as a surface to be processed. Alkaline cleaning liquid (APM), ultrapure water (DIW), and first volatile solvent (IPA) are used as the cleaning liquid, which is the processing liquid for the cleaning process. APM is a chemical mixture of ammonia water and hydrogen peroxide water, and is used to remove residual organic matter. DIW is used to wash away APM remaining on the processed surface of the substrate W after APM processing. IPA has lower surface tension and higher volatility than DIW, so it is used to replace DIW and reduce pattern collapse due to surface tension.

Moreover, in this embodiment, a second volatile solvent is used. The second volatile solvent is a solvent that has a smaller surface tension when vaporized than the first volatile solvent. Also, the vaporization temperature of the second volatile solvent is higher than that of the first volatile solvent. As such a second volatile solvent, PGMEA (propylene glycol monoethyl acetate) can be used. Also, the second volatile solvent used contains a water repellent agent. The water repellent agent replaces the hydroxyl groups (--OH) on the surface to be treated of the substrate W with functional groups (eg, --CH ₃ , C ₂ H ₅ ) to form a water-repellent film (Si--O--R (R : is a modifier capable of forming a functional group)). For example, HMDS (hexamethyldisilazane), which is a silane coupling agent, can be used as the water repellent agent. The supply of the second volatile solvent in the following description is performed in a mode of supplying the second volatile solvent containing the water repellent agent.

The reason for using PGMEA containing HMDS is that HMDS readily reacts with moisture. That is, HMDS loses its water-repellent effect on the substrate W when it reacts with moisture in the air. Therefore, HMDS can be supplied to the substrate W while being prevented from reacting with moisture in the air by mixing PGMEA with HMDS. The surface tension when PGMEA is vaporized is smaller than the surface tension when IPA is vaporized. For example, when IPA has a boiling point temperature of 82.5° C. (at the time of vaporization), the surface tension value is 15.7 mN/m. On the other hand, when the boiling point of PGMEA is 145.8° C. (at the time of vaporization), the surface tension value is 11.72 to 15.47 mN/m.

[Washing equipment]
As shown in FIG. 2, the cleaning apparatus 120 includes a cleaning chamber 11 which is a container in which cleaning processing is performed, a support section 12 that supports the substrate W, a rotation mechanism 13 that rotates the support section 12, and a cleaning liquid L that is scattered around the substrate. It has a cup 14 that receives from the periphery of W and a supply part 15 that supplies the cleaning liquid L. As shown in FIG. The supply unit 15 is provided with a nozzle 15a for dropping the cleaning liquid L and a moving mechanism 15b for moving the nozzle 15a.

The cleaning process is performed by supplying the cleaning liquid L from the nozzle 15 a to the surface to be processed of the substrate W which is supported by the support section 12 and rotated by the rotation mechanism 13 . In the cleaning process, APM is supplied to the surface of the substrate W etched by the processing apparatus 110 to perform APM cleaning. The APM remaining in is washed away with pure water. As a result, the surface to be processed of the substrate W is heaped up with the cleaning liquid L of the DIW. The cleaning chamber 11 is provided with an opening 11a for loading and unloading the substrate W, and the opening 11a can be opened and closed by a door 11b.

[Conveyor]
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. As shown in FIG. 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 undergone the etching process is unloaded from the processing apparatus 110 and loaded into the cleaning apparatus 120 in a state in which a liquid film of the cleaning liquid (DIW) L is formed on the surface of the substrate W to be processed. Further, the moving mechanism 22 moves the robot hand 21 to unload the cleaned substrate W from the cleaning apparatus 120, and a liquid film of the cleaning liquid (DIW) L is formed on the surface of the substrate W to be processed. In this state, it is carried into the drying device 300 . The reason why the substrate W is transported with the liquid film of the cleaning liquid (DIW) L formed on the surface to be processed of the substrate W is to prevent particles from adhering to the surface to be processed of the substrate W while the substrate W is being transported. It is for

[Drying device]
As shown in FIG. 2, the drying device 300 includes a drying chamber 31, a support section 32, a driving mechanism 33, a first volatile solvent supply section 34, a second volatile solvent supply section 35, a heating section 36, a cup 37 , a measuring unit 38 . The drying chamber 31 is a chamber 1a for drying the substrate W inside. The drying chamber 31 has, for example, 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 through which the substrate W is carried in and out. The opening 31a is provided so as to be opened and closed by a door 31b. The drying chamber 31 accommodates a first volatile solvent supply unit 34, a second volatile solvent supply unit 35, and a heating unit 36, which will be described later.

The drying chamber 31 is also provided with an inlet 31c and an exhaust port 31d. The inlet 31c is connected to an air supply unit 31e including a pipe, an intake valve, and an air supply device for supplying clean gas (such as _N2 ). An exhaust part 31f including a pipe, an exhaust valve, and an exhaust device for exhausting gas is connected to the exhaust port 31d. By supplying clean gas into the drying chamber 31 from the inlet 31c, the inside of the drying chamber 31 can be made into a normal atmosphere. In addition, a gas flow in the drying chamber 31 is created by supplying the gas into the drying chamber 31 from the inlet 31c and discharging the gas in the drying chamber 31 from the exhaust port 31d. As a result, the vapor of the processing liquid generated when the substrate W is heated can be discharged from the drying chamber 31 without filling the inside of the drying chamber 31 .

The support portion 32 supports the substrate W. As shown in FIG. The support portion 32 has a rotary table 32a, a plurality of holding members 32b, and a rotating shaft 32c. The rotary table 32a has a cylindrical shape with a diameter larger than that of the substrate W, and is a disk with a flat upper surface. The plurality of holding members 32b are arranged at equal intervals along the outer circumference of the substrate W, and hold the substrate W in a horizontal state with a gap between them and the upper surface of the turntable 32a. The plurality of holding members 32b are provided movably 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 rotary shaft 32c is a vertical shaft that supports the rotary table 32a from below and serves as the center of rotation.

The drive mechanism 33 is a mechanism that rotates the substrate W supported by the support portion 32 . The drive mechanism 33 has a drive source such as a motor, and rotates the support portion 32 via a rotating shaft 32c.

The first volatile solvent supply unit 34 supplies the first volatile solvent V onto the substrate W carried into the drying chamber 31 and supported by the support unit 32 . The first volatile solvent supply section 34 has a nozzle 34a, a swing arm 34b, and a swing mechanism 34c. The nozzle 34a supplies the first volatile solvent V toward the vicinity of the center of the surface of the substrate W to be processed. IPA, which is the first volatile solvent V, is supplied to the nozzle 34a from a reservoir outside the drying chamber 31 through a pipe (none of which is shown) or the like.

In the cleaning process in the cleaning apparatus 120, the surface to be processed of the substrate W is finally filled with the cleaning liquid L of DIW by the pure water rinsing process with DIW after alkaline cleaning with APM. IPA is supplied to the substrate W carried into the drying device 300 from the cleaning device 120 in such a liquid-filled state, thereby replacing the DIW with the IPA.

The swing arm 34b is provided with a nozzle 34a at its tip. or a retracted position that enables unloading. The swing mechanism 34c is a mechanism for swinging the swing arm 34b.

The second volatile solvent supply unit 35 supplies PGMEA (solvent containing HMDS) as the second volatile solvent H to the IPA that replaced the DIW on the substrate W (see FIG. 4A). The second volatile solvent supply section 35 has a nozzle 35a, a swing arm 35b, and a swing mechanism 35c. The nozzle 35a supplies the second volatile solvent H toward the vicinity of the center of the surface of the substrate W to be processed. PGMEA is supplied to the nozzle 35a from a reservoir outside the drying chamber 31 through a pipe (none of which is shown) or the like.

By supplying the second volatile solvent H containing a water-repellent agent, a water-repellent film is formed on the surface of the substrate W to be processed, so that the surface of the substrate W to be processed is repelled from hydrophilic silanol groups. By lowering the interfacial energy on the surface to be processed of the substrate W instead of water-based methyl groups, the first volatile solvent V floats and the removal of the liquid on the surface to be processed of the substrate W can be facilitated. The term "water repellency" as used herein refers to the property of repelling liquid, that is, liquid repellency, and is not limited to the property of repelling water.

The swing arm 35b is provided with a nozzle 35a at its tip. or a retracted position that enables unloading. The swing mechanism 35c is a mechanism for swinging the swing arm 35b.

The heating unit 36 is a device that heats the substrate W. As shown in FIG. The heating unit 36 is provided in the upper part of the drying chamber 31 . The heating unit 36 has a lamp 36a such as a halogen lamp or an infrared lamp. The lamp 36a is a lamp capable of emitting ultraviolet light, visible light, and infrared light. The lamps 36a of this embodiment are of a straight tube type, and a plurality of lamps 36a arranged horizontally and parallel to each other are arranged in two tiers. Since they are orthogonal to each other, they form a grid as a whole. Thereby, the heating is made uniform.

The heating unit 36 uses an electromagnetic wave (infrared radiation) having a wavelength that heats the substrate W itself more easily than the liquid itself on the surface to be processed of the substrate W, that is, the first volatile solvent V and the second volatile solvent H. can promote the generation of an air layer due to the heat of the substrate W. The heating temperature is preferably 300° C. or higher, for example.

The drying chamber 31 is provided with a window portion 36b. The window portion 36b is a member that allows electromagnetic waves from the heating portion 36 to pass therethrough. As the window portion 36b, for example, a plate-like body such as quartz can be used. The window portion 36b is provided directly below the heating portion 36 in the drying chamber 31, and by partitioning the heating portion 36 and the support portion 32, by repeating lighting of the lamp 36a, the member of the connector portion of the lamp 36a is removed. This prevents particles generated by expansion and contraction from adhering to the substrate W from above and causing metal contamination.

The cup 37 is formed in a cylindrical shape so as to surround the support portion 32 (see FIG. 2). The upper portion of the peripheral wall of the cup 37 is slanted radially inward and is open so that the substrate W on the support portion 32 is exposed. The cup 37 receives the cleaning liquid L scattered from the rotating substrate W and flows it downward. The bottom surface of the cup 37 is formed with a discharge port (not shown) for discharging the washing liquid L that flows down. The cup 37 is connected to the drive mechanism 33 and provided so as to move up and down together with the support portion 32 .

The measuring unit 38 measures the film thickness of the liquid on the substrate W which is carried into the drying chamber 31 and supported by the supporting unit 32 . The measurement unit 38 has a detection unit 38a, a swing arm 38b, and a swing mechanism 38c. For example, a laser displacement meter, a camera, or the like is used as the detection unit 38a. The swing arm 38b is provided with a detection portion 38a at its tip. It is moved to a standby position where it is evacuated from the measurement position and the substrate W can be carried in and out. The swing mechanism 38c is a mechanism for swinging the swing arm 38b.

As a film thickness measurement method by the measurement unit 38, for example, the optical interference principle can be used. As another example, it is possible to use a weight scale within the support portion 32 . 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 adjusted to the thickness of the liquid film. Convert.

[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 a drive circuit that drives each element. The control device 400 has an input device for inputting information and a display device for displaying information.

The control device 400 controls the processing device 110 , the cleaning device 120 , the conveying device 200 and the drying device 300 . For example, while rotating the substrate W supported by the support section 32, the control device 400 supplies the first volatile solvent V from the first volatile solvent supply section 34 to convert the liquid film into the first volatile solvent. The first volatile solvent V supplied onto the surface to be processed of the substrate W by the supply of the second volatile solvent H from the second volatile solvent supply unit 35 is replaced with the second solvent V. After the substitution with the volatile solvent H, the substrate W is heated by the heating unit 36 to evaporate the PGMEA, which is the second volatile solvent H, and then the water-repellent film is separated from the surface of the substrate W to be processed. . As a result, the liquid film of the second volatile solvent H is discharged by centrifugal force due to the rotation of the substrate W. As shown in FIG. For example, the boiling point of PGMEA is 140 to 150°C, and the boiling point of HMDS, which is a water repellent agent, is about 300°C. Chemical bonds in the hydrated film are broken and removed by heat. Note that the controller 400 causes the heating unit 36 to start heating when it determines that the film thickness measured by the measuring unit 38 is within the range of the predetermined threshold value.

Such a control device 400 has a mechanism control section 41 , a film thickness analysis section 42 and a heating control section 43 . The mechanism control section 41 controls the mechanism of each section. For example, the mechanism control section 41 controls the rotation speed of the support section 32 and the timing of rotation start and rotation stop by controlling the drive mechanism 33 . It also controls the swinging of the nozzle 34a and the ejection of the first volatile solvent V, the swinging of the nozzle 35a and the ejection of the second volatile solvent H, the swinging of the detector 38a and the measurement.

The film thickness analysis unit 42 analyzes the measurement result by the measurement unit 38 , that is, the thickness of the liquid films of the first volatile solvent V and the second volatile solvent H measured by the measurement unit 38 . The film thickness analysis unit 42 determines whether the thickness of the liquid film (liquid film thickness value) measured by the measurement unit 38 is within a predetermined threshold range. Then, when the film thickness analysis unit 42 determines that the measured thickness of the liquid film is within the range of the predetermined threshold value, the thickness of the liquid film is determined to be appropriate, and the heating control unit 43 A signal for instructing heating is transmitted to the heating unit 36 .

An appropriate film thickness when supplying PGMEA (second volatile solvent) containing HMDS (water repellent agent) is, for example, 100 μm or less. This film thickness delays the evaporation from the substrate W due to the heating of the heating unit 36, and is the film thickness of the liquid that can be satisfactorily dried when the drying process by the Leidenfrost phenomenon is performed. However, these numerical values are examples, and in practice, an appropriate liquid film thickness can be obtained in advance by experiments or the like. Further, 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.

[motion]
In addition to FIGS. 1 and 2, the operation of the substrate processing apparatus 1 of the present embodiment as described above is described with reference to the explanatory diagrams of FIGS. 3 to 5, the flow chart of FIG. will be described with reference to A substrate manufacturing method for manufacturing a substrate W by processing the substrate W according to the following procedure and a substrate drying method for drying the substrate W are also aspects of the present embodiment.

First, as shown in FIG. 2, the substrate W after etching processing in the processing apparatus 110 is carried into the cleaning apparatus 120 by the transfer apparatus 200 . In the cleaning apparatus 120, while the supporting unit 12 holding the substrate W rotates, the supplying unit 15 supplies APM to the center of rotation of the surface to be processed of the substrate W to perform an alkali rinse treatment, and then supplies DIW. Perform pure water rinsing by After cleaning, the transport device 200 unloads the substrate W, which is filled with the cleaning liquid L, which is DIW, from the cleaning device 120 and carries it into the drying device 300 .

As shown in FIG. 3(A), the substrate W loaded from the opening 31a of the drying chamber 31 of the drying device 300 in a state in which a liquid film (DIW) of the cleaning liquid L is formed on the surface to be processed is held by the supporting portion 32. is held by the holding member 32b (step S01). As shown in FIG. 3B, while the drive mechanism 33 rotates the substrate W together with the support portion 32 (step S02), the first volatile solvent supply portion 34 is moved to the center of rotation of the surface of the substrate W to be processed. IPA, which is the first volatile solvent V, is supplied (step S03). As a result, the centrifugal force generated by the rotation of the substrate W spreads the IPA over the entire surface of the substrate W to be processed, and alcohol rinse processing is performed in which DIW deposited on the surface of the substrate W to be processed is replaced with IPA. . Here, since DIW is replaced with IPA, which has a lower surface tension than DIW, the surface tension acting between patterns formed on the surface to be processed of the substrate W is reduced.

Then, as shown in FIG. 4A, while the drive mechanism 33 rotates the substrate W together with the support portion 32, the second volatile solvent supply portion 35 is moved to the center of rotation of the surface of the substrate W to be processed. PGMEA, which is the volatile solvent H of No. 2, is supplied (step S04). As a result, the centrifugal force generated by the rotation of the substrate W spreads the PGMEA over the entire processed surface of the substrate W, and the HMDS bonds to the processed surface of the substrate W to form a water-repellent film. That is, the first volatile solvent present on the surface to be processed of the substrate W is replaced with the second volatile solvent PGMEA, and the hydroxyl groups on the surface to be processed are replaced with functional groups to form a water-repellent film. will be The second volatile solvent has a smaller surface tension acting between patterns on the substrate W than the first volatile solvent. Therefore, the surface tension acting between the patterns is reduced. Along with this, the detection unit 38a of the measurement unit 38 measures the film thickness on the substrate W (step S06).

When the film thickness measured by the measurement unit 38 is appropriate within the range of the predetermined threshold value (YES in step S07), as shown in FIG. By turning on the lamp 36a of 36 for a predetermined time (within a range of several seconds to ten and several seconds), the substrate W is rapidly heated to a temperature at which the Leidenfrost phenomenon occurs (above the boiling point of PGMEA) (step S08). As a result, a drying process is performed in which the liquid film of the second volatile solvent H is instantly removed.

The drying process referred to here is not based on mere volatilization, but utilizes the Leidenfrost phenomenon and detachment of the water-repellent film that occur in the process of rapid heating, and the centrifugal force due to the rotation of the substrate W. FIG. That is, due to the Leidenfrost phenomenon caused by the gas layer generated at the interface between the surface of the substrate W to be processed and the liquid film of PGMEA that has not been vaporized due to heating, the liquid film floats and becomes liquid droplets (liquid droplet formation). Thereafter, the bonded state of the water-repellent film on the substrate W is released and removed. The mechanism of releasing the chemical bond is as follows. First, by heating to a high temperature, the functional group (-CHx) is thermally decomposed to break the bond with Si, and the surrounding oxygen on the substrate W bonds with the Si on the substrate W and the functional group. As a result, Si on the substrate W is oxidized to grow a thermal oxide film. In other words, although an oxide film is formed on the surface of the substrate W to be processed, there is no particular problem if this oxide film remains. In addition, the oxidized functional groups change to H ₂ O, CO ₂ and the like, but because of the high temperature, H ₂ O evaporates and CO ₂ is discharged as gas. During heating, the exhaust valve in the exhaust portion 31f may be closed to prevent vaporization of the liquid film before the formation of the gas layer, thereby generating an overheated state.

To schematically show this phenomenon, as shown in FIG. 7A, a liquid film of PGMEA containing HMDS exists on a pattern P on the surface to be processed of the substrate W via a water-repellent film R. In F, as shown in FIG. 7B, only the substrate W is instantaneously heated by lighting the lamp 36a, so that the interface between the water-repellent film of the substrate W and the PGMEA is heated faster than the PGMEA in other portions. Since the vaporization starts, a layer of gas in which the liquid film F is vaporized, that is, a gas layer G is generated.

Therefore, as shown in FIG. 7(C), the liquid film F on the pattern P instantly rises from the pattern P due to the air layer G, and as shown in FIG. ), the water-repellent film R is removed by breaking the bond between Si and —CHx on the surface of the substrate W to be processed. In this way, the water-repellent film R is removed from the substrate W after the liquid film F turns into a liquid droplet. Since it can be achieved, it can be considered that the formation of liquid droplets and the removal of the water-repellent film R occur almost simultaneously. As indicated by the black arrows in the figure, centrifugal force is applied to the liquid film F due to rotation, and the generated liquid droplets are flung off from the substrate W by the centrifugal force. ), the surface of the substrate W to be processed is dried. As described above, the functional groups that have broken bonds with Si combine with oxygen to form H ₂ O and CO ₂ , and the silane coupling agent, which is a water repellent agent, evaporates. The atmosphere preferably contains oxygen.

As shown in FIG. 8, when the liquid film F remains between the patterns P on the substrate W, the pattern P in the portion where the liquid film F remains attracts the pattern P due to the surface tension of the liquid film F. and the pattern P is destroyed. In the present embodiment, as shown in FIG. 7A, the presence of the water-repellent film R on the surface of the pattern P over the entire substrate W makes it difficult for the liquid film F to form between the patterns P. , the liquid film F between the patterns P becomes difficult to exist. In this way, since there is no liquid film F that attracts the patterns P to each other, the patterns P can be prevented from collapsing. At the same time, the water-repellent film R is separated from the substrate W, and the unnecessary water-repellent film R on the surface of the substrate W to be processed can be removed. Therefore, the substrate W can be dried while reducing the collapse of the pattern P.

After that, the heating by the heating unit 36 is stopped, and the substrate W is left to cool while being rotated (step S09). The transport device 200 unloads the substrate W from the opening 31a (step S11).

[effect]
(1) The drying apparatus (substrate drying apparatus) 300 of the present embodiment as described above includes the heating unit 36 that heats the substrate W and the first heating unit that supplies the first volatile solvent V onto the surface of the substrate W to be processed. 1 volatile solvent supply unit 34 and a water repellent agent that forms a water repellent film on the surface to be processed of the substrate W, the surface tension of which is higher than that of the first volatile solvent V when vaporized A second volatile solvent supply unit 35 for supplying a small second volatile solvent H, a heating unit 36, a first volatile solvent supply unit 34 and a second volatile solvent supply unit 35 are accommodated, A drying chamber 31 into which a substrate W having a liquid film of the processing liquid formed on the processing surface is loaded, a support section 32 for receiving the substrate W loaded into the drying chamber 31, and a substrate supported by the support section 32. By supplying the first volatile solvent V from the drive mechanism 33 that rotates the substrate W and the first volatile solvent supply unit 34, the liquid film of the processing liquid formed on the surface of the substrate W to be processed is formed into the first liquid film. 1 volatile solvent V, and supply the second volatile solvent H from the second volatile solvent supply unit 35 to form the first volatile solvent on the surface to be processed of the substrate W. V is replaced with a second volatile solvent H, a water-repellent film is formed on the surface to be treated, and the substrate W is heated by the heating unit 36 to remove the second volatile solvent containing the water-repellent agent. a control device 400 for discharging the liquid film of the second volatile solvent H by the centrifugal force caused by the rotation of the substrate W by forming an air layer between the H liquid film and the substrate W;

The substrate processing apparatus 1 of the present embodiment includes a processing apparatus 110 that processes a substrate W by supplying a first processing liquid while rotating the substrate W, and a substrate W that has been processed by the processing apparatus 110 and performs a second processing while rotating the substrate W. A cleaning device 120 that cleans by supplying a liquid, a drying device 300, and a substrate W cleaned in the cleaning device 120 in a state where a liquid film is formed by the second processing liquid supplied by the cleaning device 120. and a conveying device 200 for unloading and loading into the drying device 300 .

In the substrate drying method of the present embodiment, the substrate W on which the liquid film of the processing liquid is formed and supported by the supporting portion 32 is rotated by the driving mechanism 33 while the first volatile solvent supplying portion 34 supplies the first liquid. By supplying the volatile solvent V, the liquid film is replaced with the first volatile solvent V, and from the second volatile solvent supply part 35, a water repellent agent that forms a water repellent film is contained, and when vaporized. By supplying the second volatile solvent whose surface tension is smaller than that of the first volatile solvent V, the liquid film of the first volatile solvent V is replaced with the second volatile solvent H, and the substrate W is repelled. A hydrated film is formed, and the heating unit 36 heats the substrate W to generate an air layer between the substrate W and the liquid film of the second volatile solvent H containing a water-repellent agent, whereby the second The liquid film of the volatile solvent H is discharged by the centrifugal force due to the rotation of the substrate W.

In this manner, when the substrate W is heated while being rotated to create an overheated state, the water-repellent film makes it difficult for the liquid film to form between the patterns, and the liquid film is floated by the Leidenfrost phenomenon. , the centrifugal force can be used to instantaneously remove the entire liquid film.

Therefore, the substrate W can be dried in the same apparatus and in the same processing chamber, and a removing apparatus for removing the water-repellent film, such as a plasma processing apparatus or a UV irradiation apparatus, which is independent of the drying apparatus 300, is not required. A transfer process from the drying device 300 to the removing device is unnecessary. Therefore, the substrate processing apparatus 1 can be simplified and miniaturized, and the number of processes can be reduced to improve productivity. Furthermore, it becomes possible to remove the liquid film on the bottom of the pattern, which has been difficult with UV irradiation.

In addition, since the entire liquid film of the second volatile solvent H can be instantly removed together with the water-repellent film, it is difficult for a partial liquid film to remain on the surface of the substrate W to be processed. Therefore, it is possible to reduce the possibility of pattern collapse due to a difference in tension between adjacent patterns due to differences in the presence or absence of residual liquid film and differences in the amount of residual liquid film. Further, it is possible to reduce variations in residual liquid film caused by the difference in centrifugal force between the center and the outer periphery of the substrate W, concentration of the liquid film on the outer periphery, and the like.

(2) When the heating unit 36 heats the substrate W to generate an air layer between the substrate W and the liquid film of the second volatile solvent H supplied to the surface of the substrate W to be processed. , the water-repellent film formed on the surface of the substrate W to be processed is removed from the surface of the substrate W to be processed. Therefore, the bonding of the water-repellent film is released by heating, and the liquid film and the water-repellent film can be instantaneously removed by utilizing the centrifugal force of the rotation of the substrate W.

In addition, even if superheated liquid is supplied from a nozzle in order to detach the water-repellent film by heating, a system that handles subcritical liquid is required, which increases the safety mechanism and increases the cost. In the embodiment, by heating the substrate W with the heating unit 36 while rotating the substrate W, the liquid film can be instantaneously removed without the need for an additional device.

(3) The control device 400 has a measurement unit 38 that measures the film thickness of the first volatile solvent on the substrate W supported by the support unit 32. When it is determined that the value is within the threshold range, heating by the heating unit 36 is started. Accordingly, the substrate W can be dried after the liquid film on the substrate W is adjusted to have an appropriate film thickness. If the film thickness is too thin, the liquid film on the surface to be processed of the substrate W will be dried unevenly during heating, resulting in partial pattern collapse. Also, if the film thickness is too thick, the number of liquid droplets increases. will increase. Since the surface to be processed of the substrate W is cooled by the heat of vaporization when it comes into contact with the liquid droplets, if the number of liquid droplets becomes too large, even during rapid heating, part of the surface to be processed of the substrate W may be affected. There will be a portion where the temperature is lower than the temperature at which the Leidenfrost phenomenon occurs, that is, a portion that is dried not by rapid drying but by normal drying. In this embodiment, since the substrate W is heated after adjusting the film thickness to an appropriate value, it is possible to prevent the occurrence of such a dry state due to normal drying.

(Modification)
(1) The first volatile solvent is not limited to IPA. For example, HFE (hydrofluoroether) or the like can be used. A silane coupling agent as a water repellent agent is not limited to HMDS. For example, TMSDEA (tetramethylsilyldiethylamine) or the like can be used. The second volatile solvent is also not limited to the above PGMEA. For example, IPA may be used.

(2) As long as the processing of the processing apparatus 110 is processing that ultimately requires cleaning and drying, the content of the processing and the processing liquid are not limited to those exemplified above. The substrate W to be processed and the processing liquid are not limited to those exemplified above.

[Other embodiments]
Although the embodiment of the present invention and the modification of each part have been described above, the embodiment and the modification of each part are presented as an example 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, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims.

1 substrate processing apparatus 11 cleaning chamber 11a opening 11b door 12 support section 13 rotation mechanism 14 cup 15 supply section 15a nozzle 15b movement mechanism 20 handling device 21 robot hand 22 movement mechanism 31 drying chamber 31a opening 31b door 33 window section 32 support section 32a Rotating table 32b Holding member 32c Rotating shaft 33 Driving mechanism 33a Rotating part 33b Lifting part 34 First volatile solvent supply parts 34a, 35a Nozzles 34b, 35b Swing arms 34c, 35c Swing mechanism 35 Second volatile solvent supply Part 36 Heating part 36a Lamp 37 Cup 38 Measurement part 38a Detection part 38b Swing arm 38c Swing mechanism 41 Mechanism control part
42 Film thickness analysis unit 43 Heating control unit 100 Cleaning device 200 Conveying device 300 Drying device 400 Control device

Claims (5)

a heating unit that heats the substrate;
a first volatile solvent supply unit that supplies a first volatile solvent onto the surface to be processed of the substrate;
A second volatile solvent that contains a water-repellent agent that forms a water-repellent film and that has a lower surface tension than the first volatile solvent when vaporized is supplied onto the surface to be processed of the substrate. 2 volatile solvent supply;
drying in which the heating unit, the first volatile solvent supply unit, and the second volatile solvent supply unit are accommodated, and the substrate is carried in a state in which a liquid film of the processing liquid is formed on the surface to be processed; room and
a support for receiving the substrate carried into the drying chamber;
a drive mechanism for rotating the substrate supported by the support;
By supplying the first volatile solvent from the first volatile solvent supply unit, the liquid film of the processing liquid formed on the surface to be processed of the substrate is replaced with the first volatile solvent. let
By supplying the second volatile solvent from the second volatile solvent supply unit, the first volatile solvent formed on the surface to be processed of the substrate is transferred to the second volatile solvent. and forming the water-repellent film on the surface to be treated of the substrate,
By causing the heating unit to heat the substrate, an air layer is generated between the liquid film of the second volatile solvent containing the water repellent agent and the substrate, thereby removing the second volatile solvent. a control device for discharging the liquid film of the solvent by centrifugal force due to the rotation of the substrate;
A substrate drying apparatus comprising: When the heating unit heats the substrate to generate an air layer between the substrate and the liquid film of the second volatile solvent supplied to the surface to be processed of the substrate, the substrate 2. The substrate drying apparatus according to claim 1, wherein said water-repellent film formed on said surface to be treated is removed from said surface to be treated of said substrate. a measuring unit for measuring the film thickness of the liquid films of the first volatile solvent and the second volatile solvent on the substrate supported by the supporting unit;
3. The substrate according to claim 2, wherein the controller causes the heating unit to start heating when it is determined that the film thickness measured by the measuring unit is within a predetermined threshold range. drying equipment. a processing apparatus for processing the substrate by supplying a first processing liquid while rotating the substrate;
a cleaning device that cleans the substrate processed by the processing device by supplying a second processing liquid while rotating the substrate;
A substrate drying apparatus according to any one of claims 1 to 3;
a conveying device that unloads the substrate cleaned by the cleaning device in a state where a liquid film is formed by the second processing liquid supplied by the cleaning device, and carries the substrate into the substrate drying device;
A substrate processing apparatus comprising: A liquid film of the treatment liquid is formed, and the liquid film of the treatment liquid is formed by supplying the first volatile solvent from the first volatile solvent supply part while rotating the substrate supported by the supporting part by the driving mechanism. replacing with the first volatile solvent,
A second volatile solvent containing a water repellent agent for forming a water repellent film and having a lower surface tension than the first volatile solvent when vaporized is supplied from the second volatile solvent supply unit. replacing the liquid film of the first volatile solvent with the second volatile solvent and forming a water-repellent film on the substrate;
By heating the substrate by the heating unit, an air layer is generated between the liquid film of the second volatile solvent containing the water repellent agent and the substrate, thereby heating the liquid of the second volatile solvent. expelling the film by centrifugal force due to the rotation of the substrate;
A substrate drying method characterized by:

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