WO2020195474A1 - Substrate processing method and substrate processing device - Google Patents

Abstract

This substrate processing method comprises: a step (step S105) in which, at a first processing part, after a wet process (step S104) has been performed on a substrate that has a pattern of recesses and protrusions formed on the surface thereof, the surface of the substrate is coated with a liquid film that includes an organic solvent, and at least the surface of the liquid film is solidified to form a solidified film; steps (steps S106, S107) in which the substrate that is coated with the solidified film is transported to a second processing part; and a step (step S108) in which, at the second processing part, a dissolution liquid is supplied to the solidified film to dissolve the solidified film, and the dissolution liquid is removed from the surface of the substrate to dry the substrate. The present invention makes it possible to ensure easy transport between processing units while reliably preventing collapse of the pattern of recesses and protrusions formed on the surface of the substrate.

Description

Substrate processing method and substrate processing equipment

The present invention relates to a substrate processing method including a process of wet-treating a substrate having an uneven pattern on the surface and then drying the substrate, and a substrate processing apparatus for executing the process.

In the substrate processing technology in which a substrate having a fine uneven pattern formed on the surface is wet-treated with a liquid (for example, a cleaning treatment) and then the substrate is dried, the action of the surface tension of the liquid remaining in the pattern during the drying treatment. It is known that the pattern collapse caused by the above occurs. To solve this problem, there is a prior art in which a liquid is replaced with a fluid having a lower surface tension and then dried. As a fluid having an extremely low surface tension, for example, liquid carbon dioxide is used (see, for example, Patent Document 1).

There is also sublimation drying technology as another conventional technology. In this technique, a liquid film made of a liquid sublimable substance is formed on the surface of the substrate after the wet treatment, and then this is cooled and solidified. Then, by sublimating the solidified sublimable substance, a gas-liquid interface that causes pattern collapse is prevented from occurring (see, for example, Patent Document 2).

In these conventional techniques, the processing unit for forming a liquid film on the substrate surface and the processing unit for drying the substrate are separate bodies. Therefore, a transport mechanism is provided for transporting the substrate between these units.

Japanese Unexamined Patent Publication No. 2013-201302 Japanese Unexamined Patent Publication No. 2012-243869

In the prior art described in Patent Document 1, it is necessary to transport the substrate while maintaining the liquid film formed on the surface. Therefore, the substrate must be kept in a horizontal position at all times, and the transport speed must be relatively low. However, the surface of the substrate may be exposed due to the outflow or evaporation of the liquid due to vibration during transportation, which may cause the pattern to collapse.

On the other hand, in the conventional technique described in Patent Document 2, since the substrate surface is transported in a state of being covered with a solidified sublimation substance, it can be said that there are less restrictions during transportation. However, further miniaturization of patterns may cause problems that cannot be dealt with by this technique. The reason is as follows.

The physical property value generally known as the freezing point of a liquid is a value when the liquid is in a free space or a relatively large space. On the other hand, in the case of a liquid that has entered a fine space such as on the order of nanometers, there is a phenomenon that the freezing point is significantly lower than the above-mentioned general numerical value. Therefore, unless the cooling temperature is sufficiently lowered and a long cooling time is given, the liquid that has permeated into the fine pattern does not solidify sufficiently and remains in a liquid state. As a result, the sublimation-drying process after transportation is substantially not "sublimation" but through the liquid phase, which may cause a gas-liquid interface to collapse the pattern.

The present invention has been made in view of the above problems, and in a substrate processing technique in which a substrate having a concavo-convex pattern formed on its surface is subjected to a wet treatment and then dried, while ensuring ease of transportation between processing units. Moreover, it is an object of the present invention to provide a technique capable of surely preventing pattern collapse.

In one aspect of the substrate processing method according to the present invention, in order to achieve the above object, in the first processing section, a substrate having an uneven pattern formed on the surface is wet-treated, and then the surface of the substrate is subjected to an organic solvent. A step of covering with a liquid film containing the above, a step of coagulating at least the surface of the liquid film to form a coagulating film, a step of transporting the substrate covered with the coagulating film to a second processing unit, and the second step. The processing unit includes a step of supplying a solution to the coagulation film to dissolve the coagulation film, and a step of removing the solution from the surface of the substrate to dry the substrate.

Further, in one aspect of the substrate processing apparatus according to the present invention, in order to achieve the above object, a wet treatment is performed on a substrate having an uneven pattern formed on the surface, a treatment of covering the surface of the substrate with a liquid film, and a treatment of covering the surface of the substrate with a liquid film. The first processing unit that cools the liquid film to a temperature lower than the freezing point of the liquid constituting the liquid film to coagulate the liquid film and convert it into a coagulating film, and the substrate on which the coagulating film is formed are received and described. A second processing unit that supplies a solution to the coagulation film to dissolve the coagulation film, and a process of removing the solution from the surface of the substrate to dry the substrate, and the first processing unit. A transport mechanism for transporting the substrate on which the solidifying film is formed is provided from the processing unit to the second processing unit.

In the invention configured as described above, the transfer of the substrate from the first processing unit to the second processing unit is performed with the surface of the substrate covered with a solidifying film. Therefore, the risk of exposure of the substrate surface due to the liquid flowing off or evaporating from the substrate surface during transportation is sufficiently low. Therefore, the transfer of the substrate is relatively easy.

Then, in the second processing section to which the substrate is conveyed, the solidified film is dissolved with a dissolving solution and then the dissolving solution is removed to dry the substrate. Therefore, unlike the sublimation drying technique in which the coagulation film is directly sublimated, the fact that the liquid that has entered the inside of the pattern is not solidified does not cause the pattern to collapse. That is, according to the present invention, it is possible to prevent the collapse of even a fine pattern.

Rather, considering the ease of replacement with another fluid in the subsequent process, it is preferable that the liquid inside the pattern is not solidified. For convenience of transportation, it is sufficient that at least only the surface portion of the liquid film is solidified. Therefore, less energy and time is required to cool the liquid film. That is, it can be said that the present invention has an excellent action and effect from the viewpoint of energy efficiency and throughput.

As described above, in the present invention, in the substrate processing technique, a substrate having an uneven pattern formed on its surface is wet-treated and then dried to ensure the ease of transporting the substrate, and the pattern is fine. Can surely prevent its collapse.

The above and other objectives and novel features of the present invention will become more completely apparent by reading the following detailed description with reference to the accompanying drawings. However, the drawings are for illustration purposes only and do not limit the scope of the invention.

It is a figure which shows the schematic structure of one Embodiment of the substrate processing apparatus which concerns on this invention. It is a figure which shows the schematic structure of one Embodiment of the substrate processing apparatus which concerns on this invention. It is a figure which shows the structure and installation environment of a center robot. It is a figure which shows the substrate processing unit which performs a wet process. It is a figure which shows the substrate processing unit which performs a wet process. It is a figure which shows the substrate processing unit which performs a wet process. It is a figure which shows the substrate processing unit which performs supercritical drying processing. It is a flowchart which shows the operation of this substrate processing apparatus. It is a flowchart which shows the solidification process. It is a flowchart which shows the drying process. It is a figure which shows typically the problem which may occur in a coagulation film. It is a figure which shows typically the problem which may occur in a coagulation film. It is a figure which shows typically the problem which may occur in a coagulation film. It is a flowchart which shows another example of a solidification process. It is a figure which shows typically the state of the liquid film in this modification.

1A and 1B are diagrams showing a schematic configuration of an embodiment of a substrate processing apparatus according to the present invention. More specifically, FIG. 1A is a plan view showing a substrate processing apparatus 1 according to an embodiment of the present invention, and FIG. 1B is a side view showing a substrate processing apparatus 1. It should be noted that these figures do not show the appearance of the device, but are schematic views showing the internal structure of the device in an easy-to-understand manner by excluding the outer wall panel and other partial configurations of the device. The substrate processing device 1 is, for example, a device installed in a clean room for performing a predetermined process on a substrate.

Here, the "board" in the present embodiment includes a semiconductor substrate, a glass substrate for a photomask, a glass substrate for a liquid crystal display, a glass substrate for plasma display, a substrate for FED (Field Emission Display), a substrate for an optical disk, and a magnetic disk. Various substrates such as substrates and substrates for photomagnetic disks can be applied. In the following, a substrate processing apparatus mainly used for processing a semiconductor substrate will be described as an example with reference to the drawings. However, it is also applicable to the processing of various substrates exemplified above.

As shown in FIG. 1A, the substrate processing apparatus 1 includes a substrate processing unit 10 that processes the substrate S, and an indexer unit 20 that is coupled to the substrate processing unit 10. The indexer unit 20 includes a container holding unit 21 and an indexer robot 22. The container holding unit 21 can hold a plurality of containers C for accommodating the substrate S. The indexer robot 22 can access the container C held by the container holding portion 21 to take out the unprocessed substrate S from the container C or store the processed substrate in the container C. As the container C, a FOUP (Front Opening Unified Pod), a SMIF (Standard Mechanical Interface) pod, an OC (Open Cassette), or the like that accommodates a plurality of substrates S in a sealed state can be applied. A plurality of substrates S are housed in each container C in a substantially horizontal posture.

The indexer robot 22 has a base portion 221 fixed to the device housing, an articulated arm 222 rotatably provided around a vertical axis with respect to the base portion 221 and a hand attached to the tip of the articulated arm 222. It is equipped with 223. The hand 223 has a structure in which the substrate S can be placed and held on the upper surface thereof. Since an indexer robot having such an articulated arm and a hand for holding a substrate is known, detailed description thereof will be omitted.

The substrate processing unit 10 includes a center robot 15 arranged substantially in the center in a plan view, and a plurality of substrate processing units arranged so as to surround the center robot 15. Specifically, a plurality of (four in this example) substrate processing units 11A, 12A, 13A, and 14A are arranged facing the space in which the center robot 15 is arranged. Each of these substrate processing units 11A to 14A executes a predetermined process on the substrate S. When these processing units have the same function, parallel processing of a plurality of boards becomes possible. It is also possible to combine processing units having different functions so that different processes are sequentially executed on one substrate.

As will be described later, the substrate processing apparatus 1 of this embodiment is used for a series of treatments in which the substrate S is wet-treated with a predetermined treatment liquid and then the substrate S is dried. For this purpose, two of the four substrate processing units, 11A and 12A, are responsible for wet processing on the substrate S, and internally have a configuration for enabling this. Further, the other two substrate processing units 13A and 14A carry out a process (drying process) of removing the residual liquid from the substrate S after the wet process and drying the substrate S, and internally have a configuration for enabling this. I have.

In each of the substrate processing units 11A to 14A, a substrate processing main body that executes processing on the substrate S is housed in a processing chamber provided with a shutter that can be opened and closed on the side surface facing the center robot 15. That is, the substrate processing unit 11A has a processing chamber 110 and a shutter 111 provided on the side surface of the processing chamber 110 facing the center robot 15. The shutter 111 is provided so as to cover an opening (not shown) provided on the side surface of the processing chamber 110 facing the center robot 15. When the shutter 111 is opened, the opening is exposed, and the substrate S can be carried in and out through the opening. Further, when the processing for the substrate S is executed in the processing chamber 110, the shutter 111 is closed to block the atmosphere in the processing chamber 110 from the outside.

Similarly, the substrate processing unit 12A has a processing chamber 120 and a shutter 121 provided on the side surface of the processing chamber 120 facing the center robot 15. Further, the substrate processing unit 13A has a processing chamber 130 and a shutter 131 provided on the side surface of the processing chamber 130 facing the center robot 15. Further, the substrate processing unit 14A has a processing chamber 140 and a shutter 141 provided on the side surface of the processing chamber 140 facing the center robot 15.

Then, a set of substrate processing units arranged in the horizontal direction in this way is arranged in a plurality of stages (two stages in this example) in the vertical direction. That is, as shown in FIG. 1B, the substrate processing unit 11B is provided below the substrate processing unit 11A. The configuration and function of the substrate processing unit 11B are the same as those of the substrate processing unit 11A. Further, below the substrate processing unit 12A, a substrate processing unit 12B having the same configuration and the same function as the substrate processing unit 12A is provided. Similarly, a substrate processing unit 13B (FIG. 2) is provided below the substrate processing unit 13A, and a substrate processing unit (not shown) is also provided below the substrate processing unit 14A. The number of stages of the substrate processing unit is not limited to 2 illustrated here and is arbitrary. Further, the number of substrate processing units arranged per stage is not limited to the above.

FIG. 2 is a diagram showing the configuration and installation environment of the center robot. The center robot 15 can receive the unprocessed substrate S from the indexer robot 22, and can deliver the processed substrate S to the indexer robot 22. More specifically, the center robot 15 includes a base portion 151, an elevating base 152, a rotation base 153, a telescopic arm 154, and a hand 155. The base portion 151 is fixed to the bottom frame of the substrate processing portion 10 and supports each configuration of the center robot 15. The elevating base 152 is attached to the base portion 151, and the rotating base 153 is attached to the upper part of the elevating base 152. The elevating base 152 can be expanded and contracted in the vertical direction, and the rotation base 153 is moved up and down by this expansion and contraction movement.

The rotation base 153 is rotatable around a vertical axis with respect to the elevating base 152. The base of the telescopic arm 154 is attached to the rotation base 153, and the hand 155 is attached to the tip of the telescopic arm 154. The telescopic arm 154 expands and contracts in a predetermined range in the horizontal direction. The hand 155 has a structure in which the substrate S can be placed and held on the upper surface thereof, and the substrate S can be delivered to and from the hand 223 of the indexer robot 22. Since a hand mechanism having such a structure is known, detailed description thereof will be omitted.

By expanding and contracting the telescopic arm 154 in the horizontal direction, the substrate S held by the hand 155 can be moved in the horizontal direction. Further, by rotating the rotation base 153 with respect to the elevating base 152, the direction of horizontal movement of the substrate S can be defined. Further, the height of the substrate S, that is, the vertical position can be adjusted by raising and lowering the rotation base 153 by the elevating base 152.

In the substrate processing apparatus 1 configured as described above, the processing for the substrate S is executed as follows. In the initial state, the untreated substrate S is housed in the container C placed on the container holding portion 21. The indexer robot 22 takes out one unprocessed substrate S from the container C and hands it over to the center robot 15. The center robot 15 carries the received substrate S into a substrate processing unit that executes processing on the substrate S.

For example, when the substrate S is carried into the substrate processing unit 11A, as shown in FIG. 2, the center robot 15 adjusts the height of the rotation base 153 by the elevating base 152, and holds the substrate S held by the hand 155 on the substrate. It is positioned at the height of the shutter 111 on the side surface of the processing chamber 110 of the processing unit 11A. When the shutter 111 is opened and the telescopic arm 154 extends toward the opening on the side surface of the processing chamber 110, the substrate S is carried into the processing chamber 110. After the telescopic arm 154 is retracted, the shutter 111 is closed and the processing on the substrate S is executed in the processing chamber 110. The substrate S can be carried into another substrate processing unit in the same manner.

On the other hand, when the processed substrate S is taken out from the substrate processing unit 11A, the telescopic arm 154 enters the processing chamber 110 in which the shutter 111 is opened and the processed substrate S is taken out. The taken-out substrate S may be carried into another substrate processing unit to execute a new process, or may be returned to the container C via the indexer robot 22. The specific processing sequence in this embodiment will be described in detail later.

As shown in FIG. 2, the center robot 15 is installed in the transport space TS whose sides and upper side are separated from the external space by the partition wall 101. The substrate processing unit 11A is attached to the side portion of the partition wall 101 so that the side surface of the processing chamber 110 provided with the shutter 111 faces the transport space TS. The same applies to other substrate processing units.

In addition to the above, the substrate processing device 1 is provided with a control unit 90 for controlling the operation of each part of the device. The control unit 90 includes at least a CPU (Central Processing Unit) 91 and a memory 92. The CPU 91 causes each part of the device to execute a predetermined operation by executing a control program prepared in advance. Further, the memory 92 stores a control program to be executed by the CPU 91, data generated by the execution, and the like. The operations of the indexer robot 22 and the center robot 15 described above, the operations related to the opening and closing of the shutter in each processing chamber, various processing on the substrate S, and the like are controlled by the CPU 91 that executes the control program.

3A to 3C are diagrams showing a substrate processing unit that executes wet processing. More specifically, FIG. 3A is a diagram showing the configuration of the substrate processing unit 11A, and FIGS. 3B and 3C are diagrams for explaining the operation of the substrate processing unit 11A. Although the configuration of the substrate processing unit 11A will be described here, the configurations of the other substrate processing units 11B, 12A and the like that execute the wet processing are basically the same.

The substrate processing unit 11A includes a wet processing unit 30 as a substrate processing main body in the processing chamber 110. The wet treatment unit 30 supplies a treatment liquid to the upper surface of the substrate S to perform surface treatment, cleaning, and the like of the substrate S. Further, in order to facilitate the transfer of the substrate S after the wet treatment, the wet treatment unit 30 also executes the solidification treatment. The solidification process is a process of covering the upper surface of the substrate S with a liquid film and solidifying the upper surface of the substrate S with a solidifying film.

For this purpose, the wet processing unit 30 includes a substrate holding unit 31, a splash guard 32, a processing liquid supply unit 33, a coagulation liquid supply unit 35, and a cooling gas supply unit 34. These operations are controlled by the control unit 90. The substrate holding portion 31 has a disk-shaped spin chuck 311 having a diameter substantially equal to that of the substrate S, and a plurality of chuck pins 312 are provided on the peripheral edge of the spin chuck 311. When the chuck pin 312 abuts on the peripheral edge of the substrate S to support the substrate S, the spin chuck 311 can hold the substrate S in a horizontal posture while being separated from the upper surface thereof.

The spin chuck 311 is supported so that the upper surface is horizontal by a rotary support shaft 313 extending downward from the central portion of the lower surface thereof. The rotary support shaft 313 is rotatably supported by a rotary mechanism 314 attached to the bottom of the processing chamber 110. The rotation mechanism 314 has a built-in rotation motor (not shown). When the rotary motor rotates in response to a control command from the control unit 90, the spin chuck 311 directly connected to the rotary support shaft 313 rotates around the vertical shaft indicated by the one-point chain line. In FIG. 3A, the vertical direction is the vertical direction. As a result, the substrate S is rotated around the vertical axis while maintaining the horizontal posture.

A splash guard 32 is provided so as to surround the substrate holding portion 31 from the side. The splash guard 32 has a substantially tubular cup 321 provided so as to cover the peripheral edge portion of the spin chuck 311 and a liquid receiving portion 322 provided below the outer peripheral portion of the cup 321. The cup 321 moves up and down in response to a control command from the control unit 90. The cup 321 has a lower position in which the upper end of the cup 321 is lowered below the peripheral edge of the substrate S held by the spin chuck 311 as shown in FIG. 3A and an upper end of the cup 321 as shown in FIG. 3B. It moves up and down with and from an upper position located above the peripheral edge of the substrate S.

When the cup 321 is in the lower position, as shown in FIG. 3A, the substrate S held by the spin chuck 311 is exposed to the outside of the cup 321. Therefore, for example, it is possible to prevent the cup 321 from becoming an obstacle when the substrate S is carried in and out of the spin chuck 311.

Further, when the cup 321 is in the upper position, as shown in FIG. 3B, it surrounds the peripheral edge portion of the substrate S held by the spin chuck 311. As a result, the processing liquid that is shaken off from the peripheral edge of the substrate S when the liquid is supplied, which will be described later, is prevented from being scattered in the chamber 110, and the treatment liquid can be reliably recovered. That is, the droplets of the processing liquid that are shaken off from the peripheral edge of the substrate S by the rotation of the substrate S adhere to the inner wall of the cup 321 and flow downward, and are collected by the liquid receiving portion 322 arranged below the cup 321. It is collected. In order to collect the plurality of treatment liquids individually, a plurality of stages of cups may be provided concentrically.

The processing liquid supply unit 33 has a structure in which a nozzle 334 is attached to the tip of an arm 333 extending horizontally from a rotation support shaft 332 rotatably provided with respect to a base 331 fixed to the processing chamber 110. ing. The arm 333 swings as the rotation support shaft 332 rotates in response to a control command from the control unit 90, and the nozzle 334 at the tip of the arm 333 retracts from above the substrate S shown in FIG. 3A to the side. It moves between the retracted position and the processing position above the substrate S shown in FIG. 3B.

The nozzle 334 is connected to a processing liquid supply source (not shown) provided in the control unit 90. When an appropriate treatment liquid is delivered from the treatment liquid supply source, the treatment liquid is discharged from the nozzle 334 toward the substrate S. As shown in FIG. 3B, the spin chuck 311 rotates at a relatively low speed to rotate the substrate S, and the processing liquid Lq is supplied from the nozzle 33 positioned above the rotation center of the substrate S to supply the substrate. The upper surface Sa of S is treated with the treatment liquid Lq. As the treatment liquid Lq, a liquid having various functions such as a developing solution, an etching solution, a cleaning solution, and a rinsing solution can be used, and the composition thereof is arbitrary. Further, the treatment may be executed by combining a plurality of types of treatment liquids.

The coagulation liquid supply unit 35 also has a configuration corresponding to the treatment liquid supply unit 33. That is, the coagulation liquid supply unit 35 has a base 351, a rotation support shaft 352, an arm 353, a nozzle 354, and the like. These configurations are the same as those corresponding in the processing liquid supply unit 33. The arm 353 swings as the rotation support shaft 352 rotates in response to a control command from the control unit 90. The nozzle 354 at the tip of the arm 353 supplies a coagulating liquid for forming a coagulating film to the upper surface Sa of the substrate S after the wet treatment.

By replacing "treatment liquid Lq", "arm 333", and "nozzle 334" in the above description of FIG. 3B with "coagulant liquid Lq", "arm 353", and "nozzle 354", respectively, the coagulant liquid supply unit 35 The operation is explained. However, unlike the above-mentioned treatment liquid, the coagulation liquid is supplied to the upper surface Sa of the substrate S in a liquid state and then solidifies to become a solid.

It is assumed that the upper surface Sa of the substrate to be processed has a fine uneven pattern (hereinafter, simply referred to as "pattern") formed. At this time, in the process of drying the wet substrate S after the wet treatment, the pattern may collapse due to the surface tension of the liquid that has entered the pattern. As a method for preventing this, a method of replacing the liquid in the pattern with a liquid having a lower surface tension and then drying, and a sublimation drying method in which the upper surface Sa of the substrate is covered with a solid sublimation substance to sublimate the sublimation substance. , There is a supercritical drying method adopted in this embodiment.

In order to perform supercritical drying treatment that requires high temperature and high pressure conditions, a high pressure chamber different from the chamber that performs wet treatment is required. Therefore, it becomes necessary to transport the substrate S after the wet treatment to the high-pressure chamber. It is desirable to cover the upper surface Sa of the substrate with a liquid or solid in order to avoid collapse due to exposure of the pattern during transportation. Here, in the transport in a state where the substrate S is covered with the liquid film, special consideration is required for the handling of the substrate S that supports the liquid film. In addition, the pattern may be exposed or the liquid may be scattered in the device due to the liquid falling during transportation. In view of these points, it is preferable to carry the substrate with the upper surface Sa covered with a solid.

Therefore, in this embodiment, the substrate is transported with the upper surface Sa covered with a solidifying film. The coagulation film is formed as follows. As shown in FIG. 3B, when the substrate S is rotated at a predetermined rotation speed and the coagulating liquid Lq is supplied from the nozzle 354, the upper surface Sa of the substrate is covered with the liquid film LF of the coagulating liquid. Become. It is desirable that the coagulation liquid has good miscibility with the treatment liquid used for the wet treatment, has a lower surface tension than the treatment liquid, and has a freezing point close to room temperature. For example, when the treatment liquid contains water as a main component, isopropyl alcohol (IPA) can be preferably used.

When the liquid film LF is formed on the upper surface Sa of the substrate in this way, as shown in FIG. 3C, the nozzle 344 of the cooling gas supply unit 34 is positioned above the rotation center of the substrate S instead of the nozzle 354. The cooling gas supply unit 34 has a structure in which a nozzle 344 is attached to the tip of an arm 343 extending horizontally from a rotation support shaft 342 rotatably provided with respect to a base 341 fixed to the processing chamber 110. There is. Similar to the processing liquid supply unit 33, the rotation support shaft 342 rotates in response to a control command from the control unit 90, so that the arm 343 swings. In this way, the nozzle 344 at the tip of the arm 343 moves between the retracted position retracted laterally from above the substrate S and the processing position above the substrate S.

The nozzle 344 is connected to a cooling gas supply unit (not shown) provided in the control unit 90. The cooling gas G, which is supplied from the cooling gas supply unit and has a temperature lower than the freezing point of the coagulating liquid constituting the liquid film LF, is discharged from the nozzle 344 toward the substrate S. As a result, the liquid film LF on the substrate S is cooled from the surface side thereof. As shown in FIG. 3C, the nozzle 344 that discharges the low-temperature cooling gas G onto the upper surface Sa of the substrate on which the liquid film LF is formed scans and moves toward the outer peripheral portion of the substrate S. By doing so, the liquid film LF on the upper surface Sa of the substrate is sequentially solidified from the central portion, and finally the entire liquid film LF on the upper surface Sa of the substrate is converted into a solidified film FF formed by solidifying the coagulating liquid.

Here, in the present embodiment, it is not necessary to solidify the entire liquid film LF, and it is sufficient that at least the vicinity of the surface of the liquid film LF is solidified. That is, the entire surface of the liquid film LF may be solidified to the extent that it does not interfere with transportation, that is, to the extent that it is not deformed by vibration or the like during transportation. For example, the liquid film LF may be maintained in a liquid state between the solidifying film FF and the substrate S. By not requiring the entire coagulation, the energy consumption and processing time for coagulation can be reduced.

The process of covering the substrate S with the solidifying film is not limited to the method of cooling the liquid film LF as described above. For example, a method may be used in which a liquid having a freezing point higher than room temperature and heated above the freezing point is supplied to the substrate S and solidified by natural cooling. Alternatively, a method may be used in which a substance having a freezing point higher than room temperature is supplied to the substrate S as a solution dissolved in an appropriate solvent and solidified by volatilizing the solvent. As this method, for example, a solution in which tert-butyl alcohol (TBA) as a solidifying substance is dissolved in IPA as a solvent can be used as a coagulating liquid.

The melting point (freezing point) of TBA is approximately room temperature (25.5 ° C.). When a liquid film is formed on the substrate S with a solution in which TBA is dissolved in an IPA solvent, a solidifying film is formed from the vicinity of the surface of the liquid film as the IPA solvent on the surface evaporates. As a result, it is possible to realize a state in which a layer of a liquid solution is maintained between the substrate S and the coagulation film FF.

The substrate S carried out with the upper surface Sa covered with the solidifying film FF is conveyed to the substrate processing unit 13A and subjected to drying treatment. That is, the substrate processing unit 13A has a function of performing a drying process of removing the solidified film FF formed on the upper surface Sa of the substrate S carried in the horizontal posture and drying the substrate S as the substrate processing. As the drying treatment, supercritical drying is applied in which the substrate S is covered with a supercritical fluid and then the supercritical fluid is vaporized and removed (without going through a liquid phase). Although the configuration of the substrate processing unit 13A will be described here, the configurations of the other substrate processing units 13B, 14A, etc. that execute the drying process are basically the same.

FIG. 4 is a diagram showing a substrate processing unit that executes supercritical drying processing. More specifically, FIG. 4 is a side sectional view showing the internal structure of the substrate processing unit 13A. Since the principle of supercritical drying treatment and the basic configuration required for it are known, detailed description thereof will be omitted here. The substrate processing unit 13A includes a high-pressure chamber 130, and a drying processing unit 40 as an execution body of the drying processing is provided inside the high-pressure chamber 130. In the drying processing unit 40, a stage 41 for mounting the substrate S is installed in the high pressure chamber 130. The stage 41 holds the substrate S whose upper surface Sa is covered with a solidifying film by suction holding or mechanical holding. Since the high pressure chamber 130 has a high pressure, the internal structure is relatively simple to withstand the high pressure, and a member capable of withstanding the high pressure is used.

A rotary support shaft 42 extends downward in the center of the lower surface of the stage 41. The rotary support shaft 42 is inserted through the bottom surface of the high pressure chamber 130 via a high pressure seal rotation introduction mechanism 43. The rotation shaft 431 of the high-pressure seal rotation introduction mechanism 43 is connected to the rotation mechanism 432. Therefore, when the rotation mechanism 432 operates in response to the control command from the control unit 90, the substrate S rotates together with the stage 41 around the rotation axis in the vertical direction indicated by the alternate long and short dash line.

A fluid dispersion member 44 is provided above the stage 41 inside the high pressure chamber 130. The fluid dispersion member 44 is provided with a plurality of through holes 442 that penetrate vertically through the flat plate-shaped closing plate 441. Carbon dioxide gas is supplied to the upper part of the high-pressure chamber 130 from the carbon dioxide supply unit 45 as needed. The carbon dioxide gas is rectified by the fluid dispersion member 44 and is uniformly supplied toward the substrate S from above the substrate S.

Further, nitrogen is introduced into the high pressure chamber 130 from the nitrogen supply unit 46 as needed. Nitrogen is supplied in various forms as needed. That is, depending on the purpose of purging the gas in the high-pressure chamber 130 or cooling the inside of the chamber, it is supplied into the high-pressure chamber 130 as a gas at room temperature or a temperature rise, or as a cooled and liquefied liquid nitrogen. ..

Further, the solution is supplied from the solution supply unit 47 into the high pressure chamber 130 as needed. The dissolution liquid is a liquid for dissolving the coagulation film FF, and is supplied to the upper surface Sa of the substrate S which is carried in with the coagulation film FF formed. As the dissolution liquid, a liquid having miscibility with the coagulation liquid which is a liquid constituting the coagulation membrane FF and having a surface tension equal to or lower than that of the coagulation liquid can be used more preferably. For example, when the coagulation liquid contains IPA, an organic solvent such as IPA or acetone, or a supercritical fluid in which IPA is soluble, for example, supercritical carbon dioxide can be used as the dissolution liquid.

As will be described later, in this embodiment, the carbon dioxide gas introduced into the high-pressure chamber 130 is pressurized and liquefied to become a supercritical fluid. Therefore, when this is used as a dissolution liquid, the dissolution liquid supply unit It is not necessary to provide 47 separately.

Further, a discharge mechanism 48 is connected to the high pressure chamber 130. The discharge mechanism 48 has a function of discharging various fluids such as gas and liquid introduced into the high pressure chamber 130 as needed. The discharge mechanism 48 includes piping, a valve, a pump, and the like for this purpose. This allows the fluid in the high pressure chamber 130 to be expelled quickly if necessary.

Although not shown, the control unit 90 has a configuration for detecting the pressure and temperature in the high pressure chamber 130 and a configuration for controlling these to a predetermined value. That is, the control unit 90 has a function of controlling the pressure and temperature in the high pressure chamber 130 to predetermined target values.

Next, the operation of the substrate processing device 1 configured as described above will be described. As described above, the substrate processing apparatus 1 is an apparatus that sequentially executes a wet treatment and a drying treatment on the substrate S. The main flow of this process is as follows. That is, the substrate S is conveyed to the substrate processing unit that executes the wet treatment to perform the treatment with the processing liquid, then a coagulating film is formed by the coagulating liquid, and the substrate S is conveyed to the substrate processing unit that executes the drying treatment. The solidifying film is removed and the substrate S is dried. The specific processing contents will be described below.

Here, it is assumed that the substrate processing unit 11A executes the wet treatment and the substrate processing unit 13A executes the drying treatment on one substrate S. However, the combination of the substrate processing unit that executes the wet treatment and the substrate processing unit that executes the drying treatment is not limited to this, and is arbitrary. Further, in the following description, in order to clarify the role of each substrate processing unit, the substrate processing unit 11A or the like that executes the wet processing may be referred to as a “wet processing unit”. Further, the substrate processing unit 13A or the like that executes the drying process may be referred to as a “drying process unit”.

FIG. 5 is a flowchart showing the operation of this substrate processing device. This operation is realized by the CPU 91 executing a control program prepared in advance to cause each part of the device to perform a predetermined operation. First, the indexer robot 22 takes out one unprocessed substrate S from one of the containers C containing the unprocessed substrate (step S101). Then, the substrate S is handed over from the indexer robot 22 to the center robot 15 (step S102). The center robot 15 carries the substrate S into the substrate processing unit (wet processing unit) 11A that executes the wet processing (step S103).

The substrate processing unit 11A into which the substrate S has been carried performs wet processing on the substrate S (step S104). As described above, the content of the wet treatment is to supply a treatment liquid to the substrate S to process or clean the upper surface Sa of the substrate. A solidification process for forming the solidifying film FF is executed on the substrate S after the wet treatment (step S105).

FIG. 6 is a flowchart showing the solidification process. In the coagulation treatment, an organic solvent such as IPA is supplied as a coagulation liquid to the upper surface Sa of the substrate after the wet treatment from the nozzle 354 of the coagulation liquid supply unit 35 arranged above the rotation center of the substrate S. As a result, the treatment liquid remaining on the upper surface Sa of the substrate is replaced by the coagulating liquid, and a liquid film LF formed by the coagulating liquid is formed on the upper surface Sa of the substrate (step S201). Subsequently, the nozzle 344 that discharges the cooling gas scans and moves along the upper surface Sa of the substrate, so that the liquid film LF is cooled and solidified to form a solidified film FF (step S202).

Returning to FIG. 5, the substrate S on which the solidifying film FF is formed on the upper surface Sa by the solidification process is taken out from the substrate processing unit 11A by the center robot 15 (step S106). Then, the substrate S is carried into the substrate processing unit (drying processing unit) 13A that executes the drying process (step S107).

The substrate processing unit 13A into which the substrate S has been carried performs a drying process on the substrate S. That is, the liquid adhering to the substrate S is removed to dry the substrate S (step S108). The contents of the drying process will be described later. The processed substrate S is taken out from the substrate processing unit 13A by the center robot 15 (step S109). The removed substrate S after processing is delivered from the center robot 15 to the indexer robot 22 (step S110). The indexer robot 22 accommodates the substrate S in one of the containers C (step S111). The container C in which the processed substrate S is housed may be the container in which the untreated board S is housed, or may be another container.

If there is a substrate to be further processed (YES in step S112), the process returns to step S101, and the above processing is executed for the next substrate S. If there is no substrate to be processed (NO in step S112), the processing ends.

The flow of processing one substrate S has been described above, but in an actual device, processing for a plurality of substrates is executed in parallel. That is, at least one of the transfer of another substrate by the indexer robot 22 and the center robot 15 and the substrate processing by the other substrate processing unit while the one substrate S is being processed in one substrate processing unit at the same time. It is possible to execute one in parallel.

More specifically, for example, after the substrate S is handed over from the indexer robot 22 to the center robot 15 in step S102, the indexer robot 22 can newly access the container C and take out another substrate. .. Further, for example, after one substrate S is carried into the substrate processing unit 11A in step S103, the center robot 15 carries another substrate into another substrate processing unit, or is processed by another substrate processing unit. It is possible to carry out the board.

Therefore, when it is necessary to sequentially process a plurality of boards S, the processing on a plurality of boards can be performed in parallel by appropriately adjusting the operation sequence of each part of the device for processing each board S. And proceed. By doing so, it is possible to improve the processing throughput of the substrate processing apparatus 1 as a whole. The specific operation sequence needs to be appropriately determined according to the processing specifications, the time required for each of the above steps, the possibility of simultaneous processing, and the like.

FIG. 7 is a flowchart showing the drying process. The substrate processing unit (drying treatment unit) 13A receives the substrate S in which the upper surface Sa is covered with the solidifying film FF and executes the drying treatment. As described above, supercritical drying treatment using a supercritical fluid is performed here. Specifically, first, the dissolution liquid supply unit 47 supplies the dissolution liquid to the upper surface Sa of the substrate, thereby dissolving the coagulation film FF (step S301).

When the solution is the same as the substance constituting the coagulation film FF, the upper surface Sa of the substrate returns to the state immediately before being carried out from the wet treatment unit 11A, that is, the upper surface Sa is covered with the liquid film LF of the coagulation film. .. For example, this corresponds to the case where the coagulation film FF is formed by IPA and the solution is also IPA.

On the other hand, if the solution has the property of dissolving the solution unlike the material of the coagulation film, the upper surface Sa of the substrate will be covered with the film of the mixture of the coagulant and the solution. Further, by supplying the dissolution liquid, the coagulation liquid remaining on the upper surface Sa of the substrate can be replaced with the dissolution liquid.

After that, when the liquid film is shaken off by the rotation of the substrate S (step S302), most of the dissolved liquid on the upper surface Sa of the substrate is removed, but the dissolved liquid remains in the pattern. The shaken-out liquid is discharged by the discharge mechanism 48. In this state, carbon dioxide is introduced into the high pressure chamber 130 from the carbon dioxide supply unit 45.

Carbon dioxide gas may be liquefied by supplying carbon dioxide gas to the high pressure chamber 130 to sufficiently increase the pressure inside the chamber. In addition, liquid carbon dioxide may be introduced into the high pressure chamber 130. The liquid carbon dioxide covers the upper surface Sa of the substrate. Liquefied carbon dioxide dissolves organic solvents well. Therefore, the solution such as IPA remaining in the pattern is replaced with liquid carbon dioxide (step S303).

When liquid carbon dioxide is used as the solution, the supply of carbon dioxide in step S303 has a meaning not for substitution but as preparation for creating the next supercritical state.

Subsequently, the temperature and pressure in the high-pressure chamber 130 are adjusted to conditions that bring carbon dioxide into a supercritical state. As a result, carbon dioxide in the high-pressure chamber 130 becomes a supercritical fluid (step S304). A fluid in a supercritical state has extremely high fluidity and low surface tension. In particular, the supercritical fluid generated from carbon dioxide dissolves organic solvents such as IPA and acetone well. Therefore, the supercritical fluid of carbon dioxide penetrates deep into the fine pattern and carries away the remaining organic solvent component from the pattern. One of the reasons why carbon dioxide is suitable for supercritical drying treatment is that it becomes supercritical at relatively low pressure and low temperature.

Then, the pressure inside the high pressure chamber 130 is rapidly reduced (step S305). As a result, the supercritical fluid is directly vaporized and removed from the substrate S without passing through the liquid phase. As a result, the substrate S is in a dry state with the liquid component completely removed. The liquid component remaining in the pattern is replaced by the supercritical fluid, and the supercritical fluid is directly vaporized to avoid the problem of pattern collapse due to the surface tension of the liquid in the pattern.

In this way, the liquid remaining in the pattern is finally replaced by the supercritical fluid. Therefore, it can be said that the coagulation film FF formed during transportation does not necessarily have to be composed of a low surface tension substance. For example, even if the coagulation film FF is formed of a liquid containing water as a main component, the above-mentioned advantages during transportation can be obtained. However, since water has low solubility in carbon dioxide in a liquid or supercritical state, it is not preferable from the viewpoint of effectively performing substitution. Organic solvents such as IPA and acetone show high solubility in carbon dioxide, and these generally have lower surface tension than water. In addition, considering the nature of the treatment, it is certain that a lower surface tension is advantageous for the coagulant and the solution.

As described above, in this embodiment, in the wet processing unit 11A, the upper surface Sa of the substrate S is covered with a liquid film to be solidified, and the substrate S is conveyed in the solidified state. As a result, the convenience is improved as compared with the liquid transport, such as avoiding the exposure of the substrate upper surface Sa due to the liquid drop during the transport. On the other hand, in the drying treatment unit 13A that accepts the substrate S, the solidified film is once dissolved and then finally replaced with a supercritical fluid, so that no liquid component remains and the substrate does not collapse. Dry S.

As described above, in the present embodiment, the substrate is conveyed with the solidified film formed on the substrate, and the substrate is dried by removing the solidified film. It can be said that such a treatment content is similar to the sublimation drying treatment, which is a conventional technique for removing a coagulation film formed of a sublimable substance by sublimation. However, in the present embodiment, after the coagulation film is dissolved and returned to a liquid state, a process of replacement with a supercritical fluid and drying is adopted. This is not only for convenience in transportation, but also for the following circumstances.

8A to 8C are diagrams schematically showing problems that may occur in the coagulation film. As shown in FIG. 8A, it is assumed that a large number of fine pattern PTs are formed close to each other on the upper surface Sa of the substrate S, and these are covered with the liquid film LF of the coagulating liquid after the wet treatment. Here, the interval between adjacent pattern PTs is referred to as a gap size GS. The liquid film LF solidifies by supplying a cooling gas having a temperature lower than the freezing point to the liquid film LF. However, when the gap size GS becomes small, the following problems occur.

There is a phenomenon that the freezing point drops sharply with a liquid placed in a minute space. For example, in the case of water, as shown in FIG. 8B, the freezing point of water is 0 ° C. in a sufficiently wide space (with a large gap size GS). However, for example, the freezing point gradually decreases in a narrow gap of 100 nm or less, and for example, when the gap size GS is about 1 nm, the freezing point decreases to about (-50) ° C. It is known that IPA, which is generally used as a liquid film material, has a similar tendency.

When trying to solidify a liquid film containing water as a main component, a cooling gas having a temperature sufficiently lower than the freezing point (0 ° C.) in the free space is used. As the temperature Tg, for example, about (-5) ° C. to (-20) ° C. is considered to be realistic. However, FIG. 8B shows that when the gap size is on the order of nanometers, the liquid in the gap cannot be solidified at this temperature Tg.

As a result, as shown in FIG. 8C, even if the surface of the liquid film LF is converted to the coagulation film FF by cooling, it is possible that the liquid state remains in the deep part of the pattern depending on the cooling temperature and time. There is sex. When such a phenomenon occurs in the sublimation drying process, the drying proceeds not by the expected phase change from the solid phase to the gas phase but by the phase change from the liquid phase to the gas phase. Then, the purpose of preventing the pattern collapse due to the surface tension of the liquid is not achieved.

In the present embodiment, since the coagulation film is dissolved and then replaced with a supercritical fluid for removal, such a problem does not occur. That is, in the present embodiment, the solidified film is transported in a state of being formed, and after the solidified film is dissolved, the supercritical drying treatment is performed. Such a process is not only for the convenience of transportation, but also for the purpose of surely preventing the collapse of even a fine pattern.

In other words, in the treatment of this embodiment, the coagulating film needs to be solidified at least to the extent that the surface does not flow for convenience during transportation, and it is not necessary to completely solidify to the inner part of the pattern. This means that the temperature and treatment time conditions for cooling the liquid film LF are relaxed as compared with the case where the liquid film is completely solidified. Therefore, it is possible to reduce the energy required for cooling and shorten the cooling time. Further, from the viewpoint that the deep part may be liquid as long as the surface layer of the liquid film is solidified, the following modified examples can be established.

FIG. 9 is a flowchart showing another example of the solidification process. Further, FIG. 10 is a diagram schematically showing the state of the liquid film in this modified example. The process shown in FIG. 9 can be executed instead of the solidification process of FIG. 6 as the process applied to step S105 of FIG. In this modification, when the solidifying film is formed, a filling liquid film F1 for filling the inside of the pattern with a liquid is first formed (step S401). The filling liquid film F1 is intended to be filled in the pattern, and for the above reason, it is not required to solidify. Therefore, a substance having a sufficiently small surface tension may be selected without being restricted by the freezing point. A material that does not solidify at the cooling temperature may be intentionally selected. Further, the thickness of the liquid film F1 may be about the same as the height of the pattern PT.

Next, the coagulation liquid film F2 is formed by the coagulation liquid so as to cover the filling liquid film F1 (step S402). As the coagulation liquid film F2, a material that easily coagulates can be selected and used without being restricted by surface tension. The filling liquid film F1 and the coagulating liquid film F2 do not have to be mixed. Cooling gas is supplied to the liquid films F1 and F2 formed in this way, and the solidifying liquid film F2 solidifies (step S403).

Here, for example, if the freezing point of the liquid constituting the filling liquid film F1 is at room temperature or higher and the freezing point of the liquid constituting the solidifying liquid film F2 is at room temperature or lower, the solidifying liquid film without special cooling is performed. It is also possible to solidify F2. However, the liquid constituting the solidification liquid film F2 needs to be a liquid at the time of being supplied to the substrate S, and may be supplied in a state of being heated to a temperature slightly higher than the freezing point, for example.

In this modified example, as in the above embodiment, the coagulation liquid film F2 is coagulated, which has the advantage of improving convenience during transportation. In addition, energy consumption can be reduced by setting the cooling temperature higher than before. On the other hand, since the filling liquid film F1 is not completely solidified and is liquid, it can be easily removed after transportation. And, the pattern protection action during transportation by covering with a liquid film also functions sufficiently. In addition, the degree of freedom in selecting the liquid film forming material is increased.

In addition, there are the following differences in the comparison between this embodiment and the conventional sublimation drying treatment. In the prior art, the coagulating film covering the substrate is formed of a sublimable substance. Since the sublimable substance is highly volatile, it may volatilize during transportation and the surface of the substrate may be exposed. In addition, the volatilized sublimable substance may scatter and reprecipitate in the apparatus, which may become a source of contamination of the apparatus and the substrate being processed. Alternatively, there may be situations in which measures must be taken to prevent the scattered material from leaking out of the device. On the other hand, in the present embodiment, the coagulation film is not required to have sublimation properties, so that the possibility of such a problem occurring is greatly reduced.

As described above, in the above embodiment, the substrate processing unit 11A or the like which is a wet processing unit functions as the "first processing unit" of the present invention, and the substrate processing unit 13A or the like which is a drying processing unit of the present invention. It functions as a "second processing unit". The center robot 15 functions as the "transport mechanism" of the present invention. Further, the high pressure chamber 130 functions as the "chamber" of the present invention, and the carbon dioxide supply unit 45 functions as the "fluid supply unit" of the present invention.

The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above embodiment, the substrate processing unit 11A, the substrate processing unit 13A, and the center robot 15 corresponding to the "first processing unit", the "second processing unit", and the "conveying mechanism" of the present invention are contained in one housing. It is housed in the box and constitutes an integrated processing system. However, the present invention is also applicable to a processing system having a first processing unit and a second processing unit provided independently of each other and a transport mechanism for transporting a substrate between them.

In addition, the various chemical substances used in the above-described embodiments show some examples, and if they are consistent with the above-mentioned technical idea of the present invention, various chemical substances are used instead. It is possible.

Further, in the description of the above embodiment, the possibility that the liquid that has entered the inner part of the uneven pattern is not solidified is mentioned. However, the process itself described above is established regardless of whether or not the liquid is completely solidified in the pattern. In order to ensure that the inside of the pattern is liquid, for example, the temperature of the cooling gas is lower than the freezing point of the liquid constituting the liquid film in the free space, and the pattern of the substrate to be processed has. It may be set to be higher than the freezing point corresponding to the gap size.

Further, the substrate processing method of the present invention can also be implemented as a control program executed by a computer that controls a substrate processing apparatus having a predetermined configuration. It is also possible to distribute embodiments of the present invention on a recording medium in which this control program is recorded in a computer-readable format non-temporarily.

As described above by exemplifying a specific embodiment, in the substrate treatment method according to the present invention, for example, a coagulation film may be formed by cooling at least the surface of the liquid film. In the present invention, the liquid film is not required to solidify as a whole, as long as its surface is solidified to at least a degree suitable for transport. Therefore, a method of cooling the surface of the liquid film and its vicinity to form a solidified film is effective in terms of thermal efficiency.

In this case, for example, in the step of drying the substrate, the substrate may be dried using a supercritical fluid. According to such a configuration, the residual liquid inside the pattern can be replaced and removed with a supercritical fluid having an extremely low surface tension. Therefore, even a substrate having a fine uneven pattern can be satisfactorily dried.

For example, the second processing unit has a chamber that receives the substrate, and after replacing the solution with a liquid low surface tension liquid in the chamber, the low surface tension liquid is vaporized from the state of the supercritical fluid to dry the substrate. Can be made to. The low surface tension liquid referred to here is a liquid having a lower surface tension than the dissolution liquid. According to such a configuration, since the substrate is dried by vaporizing the liquid having a lower surface tension than the original through the supercritical state, it is possible to effectively suppress the pattern collapse due to the intervention of the liquid phase.

In these cases, carbon dioxide can be used as the supercritical fluid. The supercritical conditions in carbon dioxide are relatively low temperature and low pressure among the substances in the supercritical state. Therefore, the configuration of the device for realizing the supercritical state is relatively small, and the processing cost can be suppressed. Further, since carbon dioxide in the supercritical state dissolves the organic solvent well, it is suitable for removing the organic solvent component remaining on the substrate.

Further, for example, while at least the surface of the liquid film is converted into a coagulating film by cooling, a part of the liquid film may be maintained in a liquid state between the coagulating film and the substrate. In the present invention, the coagulation film is formed to protect the pattern and increase the portability of the substrate, and the coagulation film is dissolved after transportation. Therefore, the liquid film that protects the pattern may be liquid. By not coagulating the entire liquid film, it is possible to reduce the energy and processing time required for coagulation.

Further, for example, the liquid film may contain an additive having a melting point equal to or higher than normal temperature in addition to the organic solvent. According to such a configuration, the additive is solidified by evaporation of the organic solvent from the liquid film surface to form a solidified film, so that it is possible to omit the configuration and treatment for cooling in a normal use environment. .. As a suitable substance as such an additive, for example, tert-butyl alcohol can be used. Here, "normal temperature" refers to 5 ° C to 35 ° C, which is defined as "JIS Z8703" in the Japanese Industrial Standards in a broad sense, and 15 ° C to 25 ° C in a narrower sense. In actual operation, the ambient temperature in the environment in which the substrate processing apparatus of the present invention is installed can be regarded as "normal temperature".

Further, for example, at least one of the organic solvent and the solution contained in the liquid film may be isopropyl alcohol or acetone. These liquids have a lower surface tension than, for example, water-based liquids, and are suitable for the object of the present invention.

Further, for example, as the liquid film, a filling liquid film that fills the inside of the uneven pattern and a coagulating liquid film that covers the filling liquid film with a material different from the filling liquid film are formed to form a coagulation liquid film. The coagulation liquid film may be coagulated by cooling at a temperature lower than the freezing point of the liquid to be coagulated. According to such a configuration, a solidifying film is formed so as to cover the inside of the uneven pattern with the filling liquid film. As a result, convenience during transportation is ensured, and the coagulation film can be efficiently removed later. Further, different materials can be used for the filling liquid film and the coagulation liquid film, which increases the degree of freedom in material selection and setting of processing conditions.

In this case, for example, a liquid having a freezing point of room temperature or lower can be used as the liquid constituting the filling liquid membrane, and a liquid having a freezing point of room temperature or higher can be used as the liquid constituting the solidifying liquid membrane. According to such a configuration, no special equipment or treatment is required to realize the coexistence of the coagulation film and the liquid film in a usage environment of about room temperature.

Further, in the substrate processing apparatus according to the present invention, the second processing unit may have a solution supply unit that supplies an organic solvent as a solution to the coagulation film. According to such a configuration, the solidified film can be dissolved with an organic solvent to easily restore the state in which the substrate is covered with the liquid film.

The invention has been described above according to a specific embodiment, but this description is not intended to be interpreted in a limited sense. With reference to the description of the invention, various variations of the disclosed embodiments, as well as other embodiments of the present invention, will be apparent to those familiar with the art. Therefore, the appended claims are considered to include such modifications or embodiments without departing from the true scope of the invention.

The present invention can be applied to all substrate processing technologies including a process of transporting a substrate covered with a solidifying film, removing the solidifying film at the transporting destination, and drying the substrate. In particular, it is suitable for processing a substrate having a fine uneven pattern.

1 Substrate processing device 11A Wet processing unit, substrate processing unit (first processing unit)
13A Drying processing unit, substrate processing unit (second processing unit)
15 Center robot (conveyance mechanism)
130 High pressure chamber (chamber)
FF coagulation film LF liquid film PT pattern (concavo-convex pattern)
S board

Claims (19)

1. In the first treatment section, a step of wet-treating a substrate having an uneven pattern formed on the surface and then covering the surface of the substrate with a liquid film containing an organic solvent.
   The step of coagulating at least the surface of the liquid film to form a coagulation film,
   A step of transporting the substrate covered with the solidifying film to the second processing unit, and
   In the second processing unit, a step of supplying a solution to the coagulating film to dissolve the coagulating film, and
   A substrate processing method comprising a step of removing the solution from the surface of the substrate and drying the substrate.
2. The substrate processing method according to claim 1, wherein the coagulating film is formed by cooling at least the surface of the liquid film.
3. The substrate processing method according to claim 1 or 2, wherein in the step of drying the substrate, the substrate is dried using a supercritical fluid.
4. The second processing unit has a chamber for receiving the substrate, and has a chamber for receiving the substrate.
   The invention according to any one of claims 1 to 3, wherein the solution is replaced with a liquid low surface tension liquid in the chamber, and then the low surface tension liquid is vaporized from the state of a supercritical fluid to dry the substrate. Substrate processing method.
5. The substrate processing method according to claim 3 or 4, wherein the supercritical fluid is carbon dioxide.
6. 4. Substrate processing method.
7. The substrate treatment method according to any one of claims 1 to 6, wherein the organic solvent contained in the liquid film is isopropyl alcohol or acetone.
8. The substrate treatment method according to any one of claims 1 to 7, wherein the liquid film contains an additive having a melting point equal to or higher than room temperature in addition to the organic solvent.
9. The substrate processing method according to claim 8, wherein the additive is tert-butyl alcohol.
10. The substrate treatment method according to any one of claims 1 to 9, wherein the solution is isopropyl alcohol or acetone.
11. As the liquid film, a filling liquid film that fills the inside of the uneven pattern and a coagulation liquid film that covers the filling liquid film with a material different from the filling liquid film are formed.
    The substrate processing method according to any one of claims 1 to 10, wherein the coagulation liquid film is coagulated by cooling to a temperature lower than the freezing point of the liquid constituting the coagulation liquid film.
12. The substrate processing method according to claim 11, wherein the freezing point of the liquid constituting the solidifying liquid film is lower than the freezing point of the liquid constituting the filling liquid film.
13. The substrate processing method according to claim 11, wherein the freezing point of the liquid constituting the filling liquid film is at room temperature or lower, and the freezing point of the liquid constituting the solidifying liquid film is at room temperature or higher.
14. The substrate having the uneven pattern formed on the surface is wet-treated, the surface of the substrate is covered with a liquid film, and the liquid film is cooled to a temperature lower than the freezing point of the liquid constituting the liquid film to solidify the liquid film. , The first processing unit that executes the processing to convert to a coagulating film,
    The substrate on which the coagulation film is formed is received, a solution is supplied to the coagulation film to dissolve the coagulation film, and the solution is removed from the surface of the substrate to dry the substrate. The second processing unit that executes processing and
    A substrate processing apparatus including a transport mechanism for transporting the substrate on which the solidifying film is formed from the first processing unit to the second processing unit.
15. The first processing unit
    A treatment liquid supply unit that supplies the treatment liquid for the wet treatment to the substrate,
    A coagulation liquid supply unit that supplies the coagulation liquid for forming the liquid film to the substrate, and
    A cooling gas supply unit for supplying a cooling gas having a temperature lower than the freezing point of the coagulating liquid to the substrate is provided.
    The second processing unit
    A dissolution liquid supply unit that supplies the dissolution liquid to the substrate,
    The substrate processing apparatus according to claim 14, further comprising a fluid supply unit that supplies a fluid that replaces the solution.
16. The substrate processing apparatus according to claim 15, wherein the second processing unit has a chamber for accommodating the substrate, and the fluid supply unit supplies the fluid in a supercritical state to the internal space of the chamber.
17. The substrate processing apparatus according to claim 15 or 16, wherein the fluid is carbon dioxide.
18. The substrate processing apparatus according to any one of claims 14 to 17, wherein the solution is an organic solvent.
19. The substrate processing apparatus according to claim 18, wherein the solution is isopropyl alcohol or acetone.

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