JP2022035122A - Substrate processing device and substrate processing method - Google Patents

Abstract

To improve drying quality further more in a substrate processing technique for drying a substrate by using sublimation of a sublimable substance.SOLUTION: The present invention provides substrate processing device and substrate processing method, in which, during a liquid film formation period when a process liquid is supplied to a surface of a substrate to form a liquid film of the process liquid on the surface of the substrate, a first facing surface of an opposing member is set to face the surface of the substrate and a second facing surface of the opposing member is set to face the outer peripheral end of a base member so that the opposing member and the base member continue to form a space surrounding the substrate and inert gas is supplied in the space to change the space to an atmosphere rich in inert gas.SELECTED DRAWING: Figure 6A

Description

The present invention relates to a substrate processing apparatus and a substrate processing method for drying a substrate. The substrate is an FPD (Flat Panel) such as a semiconductor wafer, a substrate for a liquid crystal display device, and an organic EL (electroluminescence) display device.
A substrate for Display), a substrate for an optical disk, a substrate for a magnetic disk, a substrate for a magneto-optical disk, a substrate for a photomask, a ceramic substrate, a substrate for a solar cell, and the like are included.

The manufacturing process of electronic components such as semiconductor devices and liquid crystal display devices includes a step of repeatedly performing processes such as film formation and etching on the surface of a substrate to form a pattern. Further, after the pattern is formed, a cleaning treatment with a chemical solution, a rinsing treatment with a rinsing solution, a drying treatment, and the like are performed in this order, but the importance of the drying treatment is particularly increasing as the pattern becomes finer. That is, a technique for suppressing or preventing the occurrence of pattern collapse in the drying process is important. Therefore, for example, as described in Patent Document 1, a substrate processing apparatus and a substrate processing method for drying a substrate by using a sublimable substance that changes into a gas without passing through a liquid have been proposed.

Japanese Unexamined Patent Publication No. 2020-4948

In the substrate processing technique described in Patent Document 1, a solution containing a sublimating substance such as camphor and a solvent that dissolves in the sublimating substance is prepared as a drying pretreatment liquid. The drying pretreatment liquid is supplied to the surface of the substrate on which the pattern is formed. As a result, a liquid film of the drying pretreatment liquid is formed on the surface of the substrate with a desired thickness. After that, by vaporizing and removing the solvent from the liquid film, a solid film made of a sublimable substance (corresponding to an example of the "coagulant" of the present invention) is formed on the entire surface of the substrate. Sublimation then removes the solid film from the surface of the substrate.

In the prior art, the atmosphere in contact with the drying pretreatment liquid on the surface of the substrate during the period in which the drying pretreatment liquid is supplied to the surface of the substrate to form a desired liquid film (hereinafter referred to as “liquid film formation period”) is exceptional. Did not pay attention to. Therefore, it is difficult for the prior art to meet the higher drying requirements, and there is a certain limit to high quality drying.

The present invention has been made in view of the above problems, and an object of the present invention is to further improve the drying quality in a substrate processing technique for drying a substrate by utilizing sublimation of a sublimable substance.

One aspect of the present invention is a substrate processing apparatus, which has a base member and a plurality of holding members provided on the surface of the base member, and is provided with a plurality of holding members in a posture in which the surface of the substrate is directed upward. A treatment liquid containing a sublimating substance that changes to a gas without passing through a liquid and a solvent that dissolves in the sublimating substance is applied to the surface of the substrate on the surface of the substrate held by the substrate holding portion and the substrate holding portion. The processing liquid supply unit to be supplied, the coagulating body forming unit that removes the solvent from the processing liquid on the surface of the substrate to form a coagulant containing the sublimating substance, and the sublimation that sublimates the coagulant and removes it from the surface of the substrate. A first facing surface that can face the surface of the substrate held by the substrate holding portion, and a second facing surface that can face the outer peripheral end of the substrate and the outer peripheral end of the base member held by the substrate holding portion. It is provided with a facing member, a moving portion for moving the facing member relative to the substrate holding portion, and a gas supply unit for supplying an inert gas, and the processing liquid is supplied to the surface of the substrate by the processing liquid supply unit. During the liquid film forming period in which the liquid film of the treatment liquid is formed on the surface of the substrate, the moving portion keeps the facing member close to the substrate holding portion and continues to form a space surrounding the substrate by the facing member and the base member. The gas supply unit is characterized in that an inert gas is supplied to the space to create an atmosphere rich in the inert gas.

Another aspect of the present invention is a substrate processing method, which is a sublimation substance that changes to a gas without passing through a liquid with respect to the surface of the substrate held by a plurality of holding members provided on the surface of the base member. A liquid film forming step of supplying a treatment liquid containing a solvent that dissolves in a sublimable substance to form a liquid film of the treatment liquid on the surface of the substrate, and a sublimation substance by removing the gas from the liquid film on the surface of the substrate. The liquid film forming step comprises a coagulating body forming step of forming a coagulating body containing the above, and a sublimation step of sublimating the coagulating body to remove it from the surface of the substrate. The process of continuing to form a space surrounding the substrate by the facing member and the base member by facing the first facing surface of the facing member and facing the second facing surface of the facing member to the outer peripheral end of the base member, and the space is not suitable. It is characterized by having a process of supplying an active gas to make the space an inert gas-rich atmosphere.

In the above invention, before the coagulant containing the sublimable substance is formed on the surface of the substrate, a treatment liquid containing the sublimate substance and a solvent soluble in the sublimate substance is supplied to the surface of the substrate to form a liquid film of the treatment liquid. Is formed. When performing this liquid film formation, the surface of the substrate is in contact with an inert gas-rich space. As a result, the above-mentioned liquid film formation can be stably performed, and the drying quality can be improved.

It is a top view which shows the schematic structure of the substrate processing system equipped with 1st Embodiment of the substrate processing apparatus which concerns on this invention. It is a side view of the substrate processing system shown in FIG. It is a partial cross-sectional view which shows the structure of the processing unit which corresponds to 1st Embodiment of the substrate processing apparatus which concerns on this invention. It is a block diagram which shows the electric structure of the control system which controls a processing unit. It is a figure which shows typically the positional relationship of the spin base, the substrate and the facing member when the facing member is positioned at the facing position. It is a partial cross-sectional view of a facing member and a central axis nozzle. It is a schematic diagram which looked at the vicinity of the lower end portion of a central axis nozzle from below. It is a flowchart which shows the content of the substrate processing which is executed in a processing unit. It is a timing chart which shows the operation state in the substitution process, the liquid film formation process, and the solid body formation process in the 1st Embodiment of the substrate processing apparatus which concerns on this invention. It is a timing chart which shows the operation state in the substitution process, the liquid film formation process and the solid body formation process in the 2nd Embodiment of the substrate processing apparatus which concerns on this invention. It is a timing chart which shows the operation state in the substitution process, the liquid film formation process and the solid body formation process in the 3rd Embodiment of the substrate processing apparatus which concerns on this invention.

FIG. 1 is a plan view showing a schematic configuration of a substrate processing system equipped with the first embodiment of the substrate processing apparatus according to the present invention. Further, FIG. 2 is a side view of the substrate processing system shown in FIG. These drawings do not show the appearance of the substrate processing system 100, but are schematic views showing the internal structure of the substrate processing system 100 in an easy-to-understand manner by excluding the outer wall panel and other partial configurations. This substrate processing system 100 is, for example, a single-wafer type apparatus that is installed in a clean room and processes substrates W having a circuit pattern or the like (hereinafter referred to as "pattern") formed only on one main surface one by one. Then, the substrate processing method according to the present invention is executed in the processing unit 1 equipped in the substrate processing system 100. In the present specification, of the two main surfaces of the substrate, the pattern forming surface (one main surface) on which the pattern (see the reference numeral PT in FIG. 6A described later) is formed is referred to as a "surface", and the opposite side thereof. The other main surface on which the pattern is not formed is referred to as the "back surface". Further, the downwardly oriented surface is referred to as a "lower surface", and the upwardly oriented surface is referred to as an "upper surface". Further, in the present specification, the "pattern forming surface" means a surface on the substrate in which an uneven pattern is formed in an arbitrary region.

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

As shown in FIG. 1, the substrate processing system 100 includes a substrate processing unit 110 that processes a substrate W, and an indexer unit 120 coupled to the substrate processing unit 110. The indexer unit 120 is a container C for accommodating the substrate W (FOUP (Front Opening Unified Pod) for accommodating a plurality of substrates W in a sealed state, SMIF (Standard).
It has a container holding portion 121 capable of holding a plurality of mechanical interface) pods, OCs (Open Cassettes), etc. Further, the indexer unit 120 is an indexer for accessing the container C held in the container holding unit 121 to take out the unprocessed substrate W from the container C and store the processed substrate W in the container C. It is equipped with a robot 122. A plurality of substrates W are housed in each container C in a substantially horizontal posture.

The indexer robot 122 has a base portion 122a fixed to the device housing, an articulated arm 122b rotatably provided around a vertical axis with respect to the base portion 122a, and a hand attached to the tip of the articulated arm 122b. It is equipped with 122c. The hand 122c has a structure in which the substrate W can be placed and held on the upper surface thereof. Since indexer robots having such an articulated arm and a hand for holding a substrate are known, detailed description thereof will be omitted.

The board processing unit 110 includes a mounting table 112 on which the indexer robot 122 mounts the board W, a board transfer robot 111 arranged substantially in the center in a plan view, and a plurality of board transfer robots 111 arranged so as to surround the board transfer robot 111. It is equipped with a processing unit 1. Specifically, a plurality of (eight in this example) processing units 1 are arranged facing the space in which the substrate transfer robot 111 is arranged. The board transfer robot 111 randomly accesses the mounting table 112 with respect to these processing units 1 and transfers the board W to and from the mounting table 112. On the other hand, each processing unit 1 executes a predetermined processing on the substrate W. In this embodiment, these processing units 1 have the same function. Therefore, parallel processing of the plurality of substrates W is possible. If the substrate transfer robot 111 can directly deliver the substrate W from the indexer robot 122, the mounting table 112 is not always necessary. As each processing unit 1, processing units (1A to 1C) described below can be used.

FIG. 3 is a partial cross-sectional view showing the configuration of a processing unit corresponding to the first embodiment of the substrate processing apparatus according to the present invention. Further, FIG. 4 is a block diagram showing an electrical configuration of a control system that controls a processing unit. In the present embodiment, the control unit 4 is provided for each processing unit 1, but a plurality of processing units 1 may be controlled by one control unit. Further, the processing unit 1 may be controlled by a control unit (not shown) that controls the entire substrate processing system 100.

The processing unit 1 includes a chamber 20 having an internal space 21 and a spin chuck 30 housed in the internal space 21 of the chamber 20 to hold the substrate W. As shown in FIGS. 1 and 2, a shutter 23 is provided on the side surface of the chamber 20. A shutter opening / closing mechanism 22 (FIG. 4) is connected to the shutter 23, and the shutter 23 is opened / closed in response to an opening / closing command from the control unit 4. More specifically, in the processing unit 1, the shutter opening / closing mechanism 22 opens the shutter 23 when the unprocessed substrate W is carried into the chamber 20, and the unprocessed substrate W is in a face-up posture by the hand of the substrate transfer robot 111. Is carried into the spin chuck 30. That is, the substrate W is placed on the spin chuck 30 with the surface Wf facing upward. Then, when the hand of the substrate transfer robot 111 retracts from the chamber 20 after the substrate is carried in, the shutter opening / closing mechanism 22 closes the shutter 23. Then, in the internal space 21 of the chamber 20, a chemical solution, DIW (deionized water), IPA (isopropyl alcohol) treatment solution, drying pretreatment solution and nitrogen gas are supplied to the surface Wf of the substrate W as desired. Substrate processing is performed in a room temperature environment. Further, after the substrate processing is completed, the shutter opening / closing mechanism 22 opens the shutter 23 again, and the hand of the substrate transfer robot 111 carries out the processed substrate W from the spin chuck 30. As described above, in the present embodiment, the internal space 21 of the chamber 20 functions as a processing space for processing the substrate while maintaining the normal temperature environment. In the present specification, "normal temperature" means that the temperature is in the temperature range of 5 ° C to 35 ° C.

The spin chuck 30 has a plurality of chuck pins 31. In the spin chuck 30, the plurality of chuck pins 31 are provided on the peripheral edge of the upper surface of the disk-shaped spin base 32. In this embodiment, the chuck pins 31 are arranged at appropriate intervals (for example, even intervals) in the circumferential direction of the spin base 32 to grip the peripheral edge portion of the substrate W. As a result, the substrate W is held by the spin chuck 30.

A rotation shaft 33 is connected to the spin base 32. The rotation shaft 33 is rotatably provided around a rotation axis AX1 parallel to a surface normal extending from the surface center of the substrate W supported by the spin chuck 30. The rotation shaft 33 is connected to a substrate rotation drive mechanism 34 including a motor and the like. Therefore, when the motor of the substrate rotation drive mechanism 34 operates in response to the rotation command from the control unit 4 while the substrate W mounted on the spin chuck 30 is held by the chuck pin 31, the substrate W receives the rotation command. It rotates around the rotation axis AX1 at the corresponding rotation speed. Further, in the state where the substrate W is rotated in this way, the chemical liquid, the IPA treatment liquid, the DIW, and the drying pretreatment liquid are inserted from the central shaft nozzle 60 that vertically inserts the facing member 50 in response to the supply command from the control unit 4. And nitrogen gas is supplied to the surface Wf of the substrate W.

FIG. 5 is a diagram schematically showing the positional relationship between the spin base, the substrate, and the facing member when the facing member is located at the facing position. As shown in FIGS. 3 and 5, the facing member 50 is a driven type facing member that rotates according to the spin chuck 30. That is, the facing member 50 is supported by the spin chuck 30 so that the facing member 50 can rotate integrally during the substrate processing. In order to make this possible, the facing member 50 engages with the facing plate 51, the engaging member 52 provided so as to be able to move up and down with the facing plate 51, and the engaging member 52 to engage the facing plate 51 from above. It has a support portion 53 for supporting.

The facing plate 51 has a disk shape larger than the diameter of the substrate W, and has a cap shape that covers the substrate W from vertically above. More specifically, the facing plate 51 has a disk portion 511 held in a horizontal posture and a cylindrical portion 512 extending downward from the outer peripheral portion of the disk portion 511. The inner surface 513 of the facing plate 51 is a cup surface recessed downward. The inner surface 513 has a substrate facing surface 513a, a central inclined surface 513b, and an inner peripheral surface 513c.

The substrate facing surface 513a corresponds to the lower surface of the disk portion 511. More specifically, the substrate facing surface 513a is finished as a flat surface parallel to the upper surface of the substrate W and faces the surface Wf of the substrate W.

Further, the central inclined surface 513b has an inclined surface surrounded by the substrate facing surface 513a. More specifically, the central inclined surface 513b has an annular central inclined portion extending diagonally upward from the substrate facing surface 513a to the rotation axis AX1, and has the following features. The central inclined portion has a gentle slope having a constant inclination angle with respect to the rotation axis AX1. The cross section of the central slope is open downward. The inner diameter of the central inclined surface 513b increases as it approaches the lower end of the central inclined surface 513b. The lower end of the central inclined surface 513b is connected to the substrate facing surface 513a. Therefore, in a state where the facing member 50 is in the facing position, the lower end portion of the central shaft nozzle 60 is exposed downward while being surrounded by the central inclined surface 513b (see FIGS. 6A and 6B described later).

Further, the inner peripheral surface 513c corresponds to the inner side surface of the cylindrical portion 512. More specifically, the inner peripheral surface 513c has an annular inner inclined portion extending diagonally downward and outward from the substrate facing surface 513a, and has the following features. The inner inclined portion has an arcuate cross section in which the inclination angle with respect to the rotation axis AX1 continuously changes. The cross section of the inwardly inclined portion is open downward. The inner diameter of the inner peripheral surface 513c increases as it approaches the lower end of the inner peripheral surface 513c. The lower end of the inner peripheral surface 513c has an inner diameter larger than the outer diameter of the spin base 32. Therefore, as shown by the alternate long and short dash line in FIG. 3, the facing member 50 faces the outer peripheral end of the substrate W and the outer peripheral surface (outer peripheral end) 32b of the spin base 32 in a state of facing each other.

The facing plate 51 is further provided on the substrate facing surface 513a and further has a plurality of second engaging members 514 for engaging with the first engaging member 35. A through hole 515 that vertically penetrates the facing member 50 is formed in the central portion of the substrate facing surface 513a. The through hole 515 is partitioned by a cylindrical inner peripheral surface. The second engaging member 514 is provided in the same number as the first engaging member 35 and in a one-to-one correspondence with the first engaging member 35. The configurations of the first engaging member 35 and the second engaging member 514 are well known. For example, the configuration described in Japanese Patent Application Laid-Open No. 2019-57599 can be used as the engaging member 35, 514 of the present embodiment. By engaging the first engaging member 35 and the second engaging member 514, the opposing member 50 is supported by the spin base 32 via the engaging body. Then, when the spin base 32 is rotated by the operation of the motor, the facing member 50 is integrally rotated around the rotation axis AX1.

As shown in FIG. 3, the engaging member 52 has a cylindrical portion 521 that surrounds the periphery of the through hole 515 and a flange portion 522 that extends radially outward from the upper end of the cylindrical portion 521 on the upper surface of the facing plate 51. Have. The flange portion 522 is located above the flange support portion 531 which is a component of the support portion 53, and the outer circumference of the flange portion 522 has a larger diameter than the inner circumference of the flange support portion 531.

The support portion 53 has a horizontal flange support portion 531, a substantially disk-shaped support portion main body 532, and a connection portion 533 that connects the flange support portion 531 and the support portion main body 532. Then, the central axis nozzle 60 extends in the vertical direction along the vertical axis passing through the center of the opposed plate 51 and the substrate W, that is, the rotation axis AX1 so as to pass through the internal space of the support portion 53 and the facing plate 51. There is. Further, the central shaft nozzle 60 moves up and down together with the support portion 53 by the facing plate elevating drive mechanism 56. For example, as shown by the solid line in FIG. 3, when the central axis nozzle 60 and the facing member 50 are positioned at retracted positions vertically upward away from the substrate W, the tip of the central axis nozzle 60 is held by the spin chuck 30. It is separated upward from the surface Wf of the substrate W. Then, in response to the lowering command from the control unit 4, the facing plate elevating drive mechanism 56 lowers the central shaft nozzle 60 and the supporting portion 53 downward, and as shown in the alternate long and short dash line in FIG. 3 and FIG. 5, the facing member 50 Is positioned at the opposite position. As a result, the facing plate 51 of the facing member 50 is close to the surface Wf of the substrate W. As a result, the substrate W held by the spin chuck 30 is surrounded by the substrate facing surface (first facing surface) 513a, the inner peripheral surface (second facing surface) 513c, and the outer peripheral surface (outer peripheral end) 32b of the spin base 32. A semi-enclosed space SP is formed. Then, as shown in FIGS. 6A and 6B, the substrate W is confined in the semi-enclosed space SP and shielded from the surrounding atmosphere, and the chemical solution, IPA treatment solution, DIW, drying pretreatment solution and nitrogen are used from the central axis nozzle 60. Gas is supplied to the surface Wf of the substrate W.

FIG. 6A is a partial cross-sectional view of the facing member and the central shaft nozzle. FIG. 6B is a schematic view of the vicinity of the lower end portion of the central axis nozzle as viewed from below. The dotted line region in FIG. 6A is a partially enlarged view of the surface Wf of the substrate W, and an example of the pattern PT formed on the surface Wf is shown. The central axis nozzle 60 has a nozzle body 61 extending in the vertical direction along the rotation axis AX1. In the central portion of the nozzle body 61, five central piping portions (not shown) are provided so as to penetrate from the upper end surface to the lower end surface of the nozzle body 61. The lower end surface side openings of the five central piping portions function as a chemical liquid discharge port 62a, a DIW discharge port 63a, an IPA discharge port 64a, a drying pretreatment liquid discharge port 65a, and a central gas discharge port 66a, respectively.

As shown in FIG. 3, the central pipe portion having the chemical liquid discharge port 62a is connected to the chemical liquid supply unit (not shown) via the pipe 62b. A valve 62c is interposed in the pipe 62b. Therefore, when the valve 62c is opened in response to the opening / closing command from the control unit 4, the chemical solution is supplied to the central shaft nozzle 60 via the pipe 62b and discharged from the chemical solution discharge port 62a toward the center of the surface of the substrate W. Will be done. In the present embodiment, the chemical solution may have a function of cleaning the surface Wf of the substrate W, for example, sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid, phosphoric acid, acetic acid, aqueous ammonia, hydrogen peroxide solution, organic acid ( It may be a liquid containing at least one of, for example, citric acid, phosphoric acid, etc.), an organic alkali (eg, TMAH: tetramethylammonium hydrochloride, etc.), a surfactant, and a corrosion inhibitor, or any other liquid. There may be.

As shown in FIG. 3, the central pipe portion having the DIW discharge port 63a is connected to the DIW supply unit (not shown) via the pipe 63b. A valve 63c is interposed in the pipe 63b. Therefore, when the valve 63c is opened in response to the opening / closing command from the control unit 4, the IPA processing liquid is supplied to the central shaft nozzle 60 via the pipe 63b, and is directed from the DIW discharge port 63a toward the surface center portion of the substrate W. Is discharged. In the present embodiment, as will be described later, DIW is used as the rinsing solution for rinsing the surface Wf of the substrate W after the chemical solution treatment, but other rinsing solutions may be used. For example, any one of carbonated water, electrolytic ionized water, hydrogen water, ozone water, and hydrochloric acid water having a diluted concentration (for example, about 10 to 100 ppm) may be used as the rinsing solution.

As shown in FIG. 3, the central piping unit having the IPA discharge port 64a is connected to the IPA processing liquid supply unit (not shown) via the piping 64b. A valve 64c is interposed in the pipe 64b. Therefore, when the valve 64c is opened in response to the opening / closing command from the control unit 4, the IPA processing liquid is supplied to the central shaft nozzle 60 via the pipe 64b, and is directed from the IPA discharge port 64a toward the center surface of the substrate W. Is discharged. In the present embodiment, the IPA treatment liquid is used as the replacement liquid for replacing the rinsing liquid (DIW) adhering to the surface Wf of the substrate W after the rinsing treatment, but other liquids may be used. More specifically, a liquid that dissolves in both the rinsing liquid and the drying pretreatment liquid can be used as the replacement liquid. For example, it may be HFE (hydrofluoroether) or a mixed solution of IPA and HFE, or may contain at least one of IPA and HFE and other components.

As shown in FIG. 3, the central pipe portion having the drying pretreatment liquid discharge port 65a is connected to the drying pretreatment liquid supply unit (not shown) via the pipe 65b. A valve 65c is interposed in the pipe 65b. Therefore, when the valve 65c is opened in response to the opening / closing command from the control unit 4, the drying pretreatment liquid is supplied to the central shaft nozzle 60 via the pipe 65b, and the surface of the substrate W is supplied from the drying pretreatment liquid discharge port 65a. It is discharged toward the center. In the present embodiment, a solution containing a sublimating substance corresponding to a solute and a solvent that dissolves in the sublimating substance is used as the drying pretreatment liquid. Here, the sublimable substance is a substance that changes from a solid to a gas at normal temperature (synonymous with room temperature) or normal pressure (pressure in the processing unit 1, for example, a value at 1 atm or its vicinity) without passing through a liquid. May be good. The solvent may be such a substance or may be another substance. That is, the drying pretreatment liquid may contain two or more kinds of substances that change from a solid to a gas at normal temperature or pressure without passing through the liquid.

Sublimable substances include, for example, alcohols such as 2-methyl-2-propanol (also known as tert-butyl alcohol, t-butyl alcohol, and tertiary butyl alcohol) and cyclohexanol, fluorinated hydrocarbon compounds, 1,3. It may be any of 5-trioxane (also known as metaformaldehyde), camphor (also known as camphor, camphor), naphthalene, iodine, cyclohexanone oxime and cyclohexane, or it may be a substance other than these.

Solvents are from, for example, pure water, IPA, HFE, acetone, PGMEA (propylene glycol monomethyl ether acetate), PGEE (propylene glycol monoethyl ether, 1-ethoxy-2-propanol), ethylene glycol, and hydrofluorocarbon. It may be at least one species selected from the group.

As shown in FIG. 3, the central pipe portion having the central gas discharge port 66a is connected to the nitrogen gas supply unit (not shown) via the pipe 66b. A valve 66c is interposed in the pipe 66b. Therefore, when the valve 66c is opened in response to the open / close command from the control unit 4, nitrogen gas is supplied to the central shaft nozzle 60 via the pipe 66b, and is centered as shown by the alternate long and short dash arrow in FIG. 6A. The gas is discharged from the gas discharge port 66a toward the center of the surface of the substrate W.

As shown by the solid line in FIG. 3, the lower end surface 61a provided with the five discharge ports 62a to 66a retracts upward from the substrate facing surface 513a and the central inclined surface 513b in a non-blocking state. On the other hand, in the cutoff state, as shown in FIGS. 6A and 6B, the lower end surface 61a is located at the same height in the vertical direction as the substrate facing surface 513a, and the lower end portion 61b of the nozzle body 61 is surrounded by the central inclined surface 513b. It is exposed downward from the through hole 515 in the state of being removed.

On the side surface of the lower end portion 61b, six peripheral gas discharge ports 67 are provided at substantially equal angular intervals around the rotation axis AX1. As shown in FIG. 6A, peripheral piping portions 68 extending from the side surface of the nozzle body 61 to the upper end surface of the nozzle body 61 are connected to these peripheral gas discharge ports 67. As shown in FIG. 3, the peripheral pipe portion 68 is connected to the nitrogen gas supply portion (not shown) via the pipe 68b. A valve 68c is interposed in the pipe 68b. Therefore, when the valve 68c is opened in response to the opening / closing command from the control unit 4, nitrogen gas is supplied to the central shaft nozzle 60 via the pipe 68b, and is substantially horizontal from the peripheral gas discharge port 67 around the rotation axis AX1. It is discharged in the direction. As shown by the dotted arrow in FIG. 6A, the nitrogen gas discharged substantially horizontally is guided toward the surface peripheral portion of the substrate W along the central inclined surface 513b and the substrate facing surface 513a.

As described above, in the present embodiment, as shown in FIG. 6A, as a mode of supplying nitrogen gas to the substrate W,
The first supply mode (one-dot chain arrow in the figure) of supplying to the surface peripheral portion of the substrate W via the central portion of the surface of the substrate W and
A second supply mode (dotted arrow in the figure) that supplies the substrate W to the surface peripheral portion of the substrate W without passing through the central portion of the surface of the substrate W.
Exists. Then, the control unit 4 controls the opening and closing of the valves 66c and 68c to stop the supply of nitrogen gas, a mode for executing only the first supply mode, and a mode for executing only the second supply mode. The mode in which the first supply mode and the second supply mode are executed at the same time is selectively switched. Further, although not shown in the figure, the flow rate of nitrogen gas supplied in the first supply mode and the second supply mode can be independently and variably controlled according to a command from the control unit 4. There is. In the present embodiment, the nitrogen gas is used as the "inert gas" of the present invention, but in addition to this, an inert gas such as dehumidified argon gas may be used.

Further, in the processing unit 1, an exhaust tub 70 is provided so as to surround the spin chuck 30. Further, a plurality of cups 72 arranged between the spin chuck 30 and the exhaust tub 70, and a plurality of guards for receiving the chemical liquid, the rinsing liquid (DIW), the IPA treatment liquid, and the pre-drying treatment liquid scattered around the substrate W. 73 is provided. Further, the guard elevating drive mechanism 71 is connected to the guard 73. The guard elevating drive mechanism 71 independently elevates and elevates the guard 73 in response to an elevating command from the control unit 4. Further, an exhaust mechanism 74 is connected to the exhaust tub 70. The exhaust mechanism 74 exhausts the space surrounded by the inner bottom surface of the chamber 20, the exhaust tub 70, and the guard 73.

The control unit 4 has an arithmetic unit such as a CPU, a fixed memory device, a storage unit such as a hard disk drive, and an input / output unit. The storage unit stores the program executed by the arithmetic unit. Then, the control unit 4 executes the substrate processing shown in FIG. 7 by controlling each unit of the device according to the above program.

FIG. 7 is a flowchart showing the contents of the substrate processing executed in the processing unit. The processing target in the substrate processing system 100 is, for example, a silicon wafer, and an uneven pattern PT (see FIG. 6A) is formed on the surface Wf which is a pattern forming surface. The pattern PT may constitute a logic circuit, a DRAM (Dynamic Random Access Memory), or a PRAM (Phase-change Random Access Memory) that utilizes the peculiar properties of a chalcogenide-based alloy. The pattern PT may be one in which line-shaped patterns formed by fine trenches are repeatedly arranged. Further, the pattern PT may be formed by providing a plurality of fine holes (voids or pores) in the thin film. The pattern PT includes, for example, an insulating film. Further, the pattern PT may include a conductor film. More specifically, the pattern PT is formed of a laminated film in which a plurality of films are laminated, and may further include an insulating film and a conductor film. The pattern PT may be a pattern PT composed of a monolayer film. The insulating film may be a silicon oxide film or a silicon nitride film. Further, the conductor film may be an amorphous silicon film into which impurities for lowering the resistance are introduced, or may be a metal film (for example, a TiN film). Further, the pattern PT may be formed at the front end or may be formed at the back end. Further, the pattern PT may be a hydrophobic film or a hydrophilic film. As the hydrophilic film, for example, a TEOS film (a kind of silicon oxide film) is included.

Further, each step shown in FIG. 7 is processed in an atmospheric pressure environment unless otherwise specified. Here, the atmospheric pressure environment refers to an environment of 0.7 atm or more and 1.3 atm or less, centered on the standard atmospheric pressure (1 atm, 1013 hPa). In particular, when the substrate processing system 100 is arranged in a clean room where the pressure is positive, the environment of the surface Wf of the substrate W becomes higher than 1 atm.

Before the unprocessed substrate W is carried into the processing unit 1, the control unit 4 gives a command to each unit of the device to set the processing unit 1 in the initial state. That is, the shutter 23 (FIGS. 1 to 3) is closed by the shutter opening / closing mechanism 22. The spin chuck 30 is positioned and stopped at a position suitable for loading the substrate W by the substrate rotation drive mechanism 34, and the chuck pin 31 is opened by a chuck opening / closing mechanism (not shown). The facing plate 51 is positioned at the retracted position by the facing plate elevating drive mechanism 56. As a result, the support of the facing plate 51 by the spin base 32 is canceled, and the rotation of the facing plate 51 is stopped. The guards 73 are all moved downward and positioned. Further, the valves 62c to 66c and 68c are all closed.

When the unprocessed substrate W is conveyed by the substrate transfer robot 111, the shutter 23 opens. Along with the opening of the shutter 23, the substrate W is carried into the internal space 21 of the chamber 20 by the substrate transfer robot 111, and is delivered to the spin chuck 30 in a face-up state with the surface Wf facing upward. Then, the chuck pin 31 is closed, and the substrate W is held by the spin chuck 30 (step S1: substrate loading).

Following the loading of the substrate W, the substrate transfer robot 111 retracts out of the chamber 20, and the shutter 23 closes again. After that, the control unit 4 controls the facing plate elevating drive mechanism 56 to arrange the facing plate 51 at the facing position. As a result, as shown in FIG. 5, the engaging member 514 provided on the facing plate 51 is received by the engaging member 35, and the facing plate 51 and the central shaft nozzle 60 are supported by the spin base 32. Further, the facing plate 51 and the spin base 32 are close to each other to form a semi-enclosed space SP. As a result, the substrate W held by the spin chuck 30 is confined in the space SP and shielded from the surrounding atmosphere. In this embodiment, the facing plate 51 is positioned at the facing position until the sublimation step (step S8) described later is completed.

Following the completion of closing the substrate W into the space SP, the control unit 4 controls the motor (not shown) of the substrate rotation drive mechanism 34 to set the rotation speed of the spin base 32 to a predetermined chemical solution processing speed (about 10). Within the range of ~ 1200 rpm, for example, about 800 rpm) is increased to maintain the chemical treatment rate. Along with the rotation of the spin base 32, the facing plate 51 is rotated around the rotation axis AX1 and the substrate W is rotated around the rotation axis AX1 (step S2: substrate rotation start). By the time the chemical solution treatment proceeds, the control unit 4 raises the guard 73 corresponding to the chemical solution treatment so that the guard 73 is connected to the inner peripheral surface 513c of the facing plate 51 and the outer peripheral surface 32b of the spin base 32. Facing the gap GP of.

When the rotation speed of the substrate W reaches the chemical treatment speed, the control unit 4 then opens the valve 62c. As a result, the chemical solution is discharged from the chemical solution discharge port 62a of the central axis nozzle 60 and supplied to the surface Wf of the substrate W. On the surface Wf of the substrate W, the chemical solution receives centrifugal force due to the rotation of the substrate W and moves to the peripheral edge of the substrate W. As a result, the entire surface Wf of the substrate W is washed with the chemical solution (step S3). At this time, the chemical solution that has reached the peripheral edge of the substrate W is discharged from the peripheral edge of the substrate W to the side of the substrate W, and is sent to the waste liquid treatment facility outside the machine via the guard 73. The chemical solution cleaning by supplying the chemical solution is continued for a predetermined cleaning time, and after that, the control unit 4 closes the valve 62c and stops the discharge of the chemical solution from the central shaft nozzle 60.

Following the chemical washing, a rinsing treatment with a rinsing solution (DIW) is performed (step S4). In this DIW rinse, the control unit 4 opens the valve 63c. As a result, DIW is supplied as a rinsing solution from the DIW discharge port 63a of the central axis nozzle 60 to the central portion of the surface Wf of the substrate W that has been subjected to the chemical solution cleaning treatment. Then, the DIW receives the centrifugal force due to the rotation of the substrate W and moves to the peripheral edge portion of the substrate W. As a result, the chemical solution adhering to the substrate W is washed away by the DIW. At this time, the DIW discharged from the peripheral edge portion of the substrate W is discharged from the peripheral edge portion of the substrate W to the side of the substrate W, and is sent to the waste liquid treatment facility outside the machine in the same manner as the chemical solution. This DIW rinsing is continued for a predetermined rinsing time, after which the control unit 4 closes the valve 63c and stops the discharge of the DIW from the central axis nozzle 60.

After the completion of the DIW rinse, a substitution process (step S5), a liquid film forming step (step S6), and a solid body forming step (step S7) are executed.

FIG. 8 is a timing chart showing operating conditions in the substitution process, the liquid film forming step, and the solidified body forming step in the first embodiment of the substrate processing apparatus according to the present invention. The “flow rate of vertical N2” in the figure means the flow rate of nitrogen gas discharged downward from the central gas discharge port 66a. That is, when the control unit 4 opens the valve 66c, nitrogen gas is supplied from the central gas discharge port 66a to the central portion of the surface Wf of the substrate W. This nitrogen gas is supplied to the entire substrate W along the surface Wf of the substrate W (first supply mode: see the alternate long and short dash line in FIG. 6A). The flow rate of the nitrogen gas supplied via the central portion of the surface in this way is the “vertical N2 flow rate”. On the other hand, the “horizontal N2 flow rate” in the figure means the flow rate of nitrogen gas discharged in the substantially horizontal direction from the six peripheral gas discharge ports 67. That is, when the control unit 4 opens the valve 68c, the nitrogen gas is discharged radially around the rotation axis AX1. This nitrogen gas is supplied to the surface peripheral portion of the substrate W along the central inclined surface 513b and the substrate facing surface 513a (second supply mode: see the dotted line in FIG. 6A). The flow rate of nitrogen gas supplied to the peripheral edge of the surface without passing through the central portion of the surface is the “horizontal N2 flow rate”.

In the replacement process (step S5), the control unit 4 controls the motor (not shown) of the substrate rotation drive mechanism 34 to adjust the rotation speed of the substrate W to a predetermined first rotation speed V1, and the first rotation speed thereof. Keep it at V1. Further, the control unit 4 adjusts the flow rates of nitrogen gas from the central gas discharge port 66a and the peripheral gas discharge port 67 to "VF1" and "HF1", respectively. As a result, nitrogen gas is supplied to the semi-enclosed space SP, and the space SP becomes nitrogen-rich. Further, it is possible to effectively prevent outside air from entering the space SP from the surrounding atmosphere through the gap GP (see FIG. 5) which is the only place where the space SP and the surrounding atmosphere communicate with each other. As a result, the space SP becomes a low oxygen environment. Here, "hypoxia" means that the oxygen concentration is 100 ppm or less.

Further, the control unit 4 makes the guard 73 corresponding to the replacement process face the gap GP. Then, the control unit 4 opens the valve 64c. As a result, the IPA treatment liquid is discharged as a low surface tension liquid from the IPA discharge port 64a of the central axis nozzle 60 toward the central portion of the surface Wf of the substrate W to which the DIW is attached. The IPA treatment liquid supplied to the surface Wf of the substrate W receives centrifugal force due to the rotation of the substrate W and spreads over the entire surface Wf of the substrate W. As a result, the DIW (rinse liquid) adhering to the surface Wf is replaced by the IPA treatment liquid in the entire surface Wf of the substrate W. The IPA treatment liquid moving on the surface Wf of the substrate W is discharged from the peripheral edge of the substrate W to the side of the substrate W, is received by the guard 73, and is sent to the collection equipment along a collection route (not shown). Be done. This IPA replacement is continued for a predetermined replacement time, and after that, the control unit 4 closes the valve 64c and stops the discharge of the IPA processing liquid from the central axis nozzle 60.

Following the IPA substitution, a liquid film forming step (step S6) is performed. In this liquid film forming step, the drying pretreatment liquid supply step (step S6a) for supplying the drying pretreatment liquid, the spin-off step (step S6b), and the sublimation substance contained in the drying pretreatment liquid are submerged between the pattern PTs. It has a sublimable substance sublimation step (step S6c) to cause the sublimation. These steps S6a to 6c are executed in this order.

In the drying pretreatment liquid supply step (step S6a), as shown in FIG. 8, the control unit 4 sets the rotation speed of the substrate W, the flow rate of the vertical N2, and the flow rate of the horizontal N2 to the values “V1” in the replacement process, respectively. It is maintained at "VF1" and "HF1". The control unit 4 makes the guard 73 corresponding to the drying pretreatment liquid supply process face the gap GP. The control unit 4 opens the valve 65c. As a result, the drying pretreatment liquid is discharged from the drying pretreatment liquid discharge port 65a of the central axis nozzle 60 toward the central portion of the surface Wf of the substrate W to which the replacement liquid is attached. The drying pretreatment liquid supplied to the surface Wf of the substrate W receives centrifugal force due to the rotation of the substrate W and spreads over the entire surface Wf of the substrate W. As a result, the IPA treatment liquid is replaced with the drying pretreatment liquid over the entire surface Wf of the substrate W, and a relatively thick liquid film of the drying pretreatment liquid is formed. The discharge of the drying pretreatment liquid is continued for a predetermined time, and after that, the control unit 4 closes the valve 65c and stops the discharge of the drying pretreatment liquid from the central axis nozzle 60.

In the spin-off step (step S6b), the control unit 4 closes the valves 66c and 68c to stop the discharge of nitrogen gas, and controls the motor (not shown) of the substrate rotation drive mechanism 34 to control the rotation speed of the substrate W. The speed is increased to a spin-off speed V3 higher than the first rotation speed V1. Then, the control unit 4 maintains the spin-off speed V3 for a predetermined time. As a result, the excess drying pretreatment liquid is removed from the surface Wf of the substrate W, and the thickness of the liquid film of the drying pretreatment liquid is adjusted to a desired thickness.

In the sublimation material subsidence step (step S6c), the control unit 4 controls the motor of the substrate rotation drive mechanism 34 while stopping the discharge of nitrogen gas to make the rotation speed of the substrate W higher than that of the first rotation speed V1. Decelerate to a lower second rotation speed V2. Then, the control unit 4 waits for the predetermined time to elapse. During this waiting time of a predetermined time, the sublimable substance present in the liquid film of the drying pretreatment liquid sinks and is filled between the pattern PTs. Further, in the latter half of the predetermined time, the control unit 4 opens the valve 66c. As a result, nitrogen gas is discharged to the central portion of the surface of the substrate W. As described above, in the present embodiment, in the latter half of the sublimation material subsidence step, the nitrogen gas having the flow rate VF1 is vertically discharged from the central gas discharge port 66a in the first supply mode. Therefore, the following effects can be obtained. By performing the nitrogen gas control before the solidified body forming step (step S7) described later, the solvent of the drying pretreatment liquid in the vicinity of the central portion of the surface Wf of the substrate W can be evaporated to increase the solute concentration. Moreover, by horizontally discharging the nitrogen gas in the subsequent solidification body forming step (step S7), the solute concentration on the surface Wf of the substrate W can be made uniform. With these, the film thickness of the solidified body can be made uniform.

When a liquid film of the drying pretreatment liquid suitable for sublimation drying is formed on the surface Wf of the substrate W, the solidified body forming step (step S7) is executed. The control unit 4 controls the motor of the substrate rotation drive mechanism 34 to increase the rotation speed of the substrate W to be higher than the first rotation speed V1. More specifically, the control unit 4 increases the spin-off speed to V3 and increases the flow rate of nitrogen gas. More specifically, the flow rate of the nitrogen gas discharged from the central gas discharge port 66a is increased from the flow rate VF1 to the flow rate VF2, and the valve 68c is opened to discharge the nitrogen gas from the peripheral gas discharge port 67. The solvent in the liquid film is removed within a predetermined time from the increase in the rotation speed and the nitrogen gas, and a coagulated body of the sublimable substance is formed.

Following the formation of such a solid body, the control unit 4 further increases the rotation speed to V4 (> V3) and maintains the rotation speed V4. Further, the control unit 4 opens the valve 68c to flow the flow rate of the nitrogen gas discharged from the peripheral gas discharge port 67 while maintaining the flow rate of the nitrogen gas discharged from the central gas discharge port 66a at the flow rate VF2. The sublimation step (step S8) is executed by increasing the flow rate from HF2 to the flow rate HF3 to increase the flow rate of the nitrogen gas flowing along the surface Wf of the substrate W.

The sublimation step may be carried out by taking over the final speed and the final flow rate of the solidified body forming step, but in the present embodiment, the rotation speed and the flow rate are stepped up. Therefore, the sublimation speed is increased, the pattern collapse prevention at the time of sublimation, and the effect of shortening the drying time can be obtained. Then, when a predetermined time elapses from the step-up, the control unit 4 stops and controls the motor of the substrate rotation drive mechanism 34 to stop the rotation of the substrate W (step S9: substrate rotation stop).

Subsequently, the control unit 4 controls the facing plate elevating drive mechanism 56 to raise the facing plate 51 from the facing position and position it in the retracted position. Further, the control unit 4 retracts all the guards 73 downward from the gap GP.

After that, after the control unit 4 controls the shutter opening / closing mechanism 22 to open the shutters 23 (FIGS. 1 to 3), the substrate transfer robot 111 enters the internal space of the chamber 20 and is held by the chuck pin 31. The released processed substrate W is carried out of the chamber 20 (step S10). When the loading of the substrate W is completed and the substrate transfer robot 111 separates from the processing unit 1, the control unit 4 controls the shutter opening / closing mechanism 22 to close the shutter 23.

As described above, in the first embodiment, while the liquid film forming step (step S6) is being executed, the facing plate 51 and the spin base 32 are in close proximity to each other to form a semi-sealed space SP. The space SP has a nitrogen gas-rich atmosphere. Then, a liquid film of the drying pretreatment liquid is formed in a state where the surface Wf of the substrate W is in contact with the space SP rich with the inert gas. Thereby, the liquid film formation can be stably performed. For example, when the substrate W on which the pattern PT for forming a logic circuit, DRAM or PRAM is formed on the surface Wf is dried by the prior art, there arises a problem that a part of the pattern PT, particularly a line width portion, is oxidized. was there. On the other hand, according to the present embodiment, the liquid film of the drying pretreatment liquid is formed in the nitrogen gas-rich space SP. That is, liquid film formation is performed in a hypoxic state. As a result, the above problem can be effectively suppressed.

Further, in the first embodiment, nitrogen gas is discharged from both the central gas discharge port 66a and the peripheral gas discharge port 67 from the drying pretreatment liquid supply step (step S6a). Therefore, the space SP can have a nitrogen gas-rich atmosphere from the initial stage of the liquid film formation period, and the liquid film formation can be performed more stably. Here, it is not essential to simultaneously discharge the nitrogen gas from both discharge ports 66a and 67, and the nitrogen gas discharge timing may be staggered from each other, or the nitrogen gas may be discharged from only one discharge port.

As described above, in the first embodiment, the chuck pin 31 and the spin base 32 correspond to examples of the "base member" and the "holding member" of the present invention, respectively, and the spin chuck 30 provided with these corresponds to the "base member" and the "holding member" of the present invention, respectively. It corresponds to an example of "board holding part". The drying pretreatment liquid and the nitrogen gas correspond to examples of the "treatment liquid" and the "inert gas" of the present invention, respectively. The central axis nozzle 60 for discharging the drying pretreatment liquid and nitrogen gas functions as the “treatment liquid supply unit”, the “gas supply unit”, the “coagulant forming unit” and the “sublimation unit” of the present invention. The central gas discharge port 66a and the peripheral gas discharge port 67 provided in the central shaft nozzle 60 correspond to an example of the "first gas discharge port" and the "second gas discharge port" of the present invention, respectively. The valves 66c and 68c correspond to an example of the "first gas discharge switching unit" and the "second gas discharge switching unit" of the present invention, respectively. The facing plate elevating drive mechanism 56 corresponds to an example of the "moving portion" of the present invention. The substrate rotation drive mechanism 34 corresponds to an example of the "rotating portion" of the present invention. The execution period of step S6 corresponds to an example of the "liquid film formation period" of the present invention. Of these, steps S6a and S6c correspond to examples of the "initial stage of the liquid film formation period" and the "end stage of the liquid film formation period" of the present invention, respectively. The execution period of step S6c corresponds to an example of the "sublimation substance subsidence period" of the present invention. The period during which the flow rate of the vertical N2 is maintained at zero during the sublimation substance sublimation period (step S6c) corresponds to an example of the “first half of the sublimation substance sublimation period” of the present invention, and the flow rate of the vertical N2 is the value “VF1”. The period maintained at "" corresponds to an example of "the latter half of the sublimation substance sublimation period" of the present invention.

FIG. 9 is a timing chart showing operating conditions in the substitution process, the liquid film forming step, and the solidified body forming step in the second embodiment of the substrate processing apparatus according to the present invention. The major difference between the second embodiment and the first embodiment is the supply mode of nitrogen gas in the liquid film forming step (step S6) and the solidified body forming step (step S7). Since other configurations and operations are basically the same as those of the first embodiment, the differences will be mainly described here, and the same or corresponding reference numerals will be given and the description thereof will be omitted.

In the second embodiment, as shown in FIG. 9, the discharge of nitrogen gas from the peripheral gas discharge port 67 continues from the drying pretreatment liquid supply step (step S6a), followed by the spin-off step (step S6b) and the sublimation substance sublimation step. It is also continued in (step S6c). On the other hand, the discharge of nitrogen gas from the central gas discharge port 66a is stopped at the same time as the completion of the drying pretreatment liquid supply step (step S6a), and the discharge stop state is the spin-off step (step S6b) and the sublimable substance sublimation step (step). It is also continued in S6c). As described above, in the second embodiment, nitrogen gas is supplied to the space SP in the liquid film forming step (step S6), and the hypoxic state is surely continued.

In the solidified body forming step (step S7), the nitrogen gas discharge flow rate from the peripheral gas discharge port 67 is increased from the value HF1 to the value HF2, while the nitrogen gas discharge flow rate from the central gas discharge port 66a is maintained at zero. Has been done. That is, the nitrogen gas is not supplied to the central surface portion of the substrate W, but is supplied to the surface peripheral portion of the substrate W along the central inclined surface 513b of the facing plate 51 and the substrate facing surface 513a.

Then, when the solidified body is formed after a certain period of time, the control unit 4 opens the valve 66c and starts supplying nitrogen gas from the central gas discharge port 66a to the central portion of the surface of the substrate W (discharge flow rate VF2). Further, in synchronization with this, the discharge flow rate of the nitrogen gas from the peripheral gas discharge port 67 is increased from the value HF2 to the value HF3. In this way, as shown in FIG. 6A, a large amount of nitrogen gas is supplied to the entire surface Wf of the substrate W, and the solidified body is efficiently sublimated (step S8).

As described above, according to the second embodiment, not only the same action and effect as those of the first embodiment can be obtained, but also the action and effect described below can be obtained. The present embodiment has two modes of supplying nitrogen gas, and as in the first embodiment, the supply to the central portion of the surface of the substrate W may be prioritized. In this case, the gas component is generated from the central part of the surface before the peripheral part of the surface and flows to the peripheral part of the surface. Since the space SP of this device is in a semi-sealed state, gas components tend to stay at the peripheral edge of the surface. Therefore, the subsequent process cannot be performed favorably, and pattern collapse may occur at the peripheral edge of the surface. On the other hand, in the second embodiment, since the nitrogen gas is supplied to the surface peripheral portion before the surface central portion, it is possible to effectively prevent the pattern collapse at the surface peripheral portion. Moreover, since the flow rate of the nitrogen gas supplied to the peripheral portion of the surface is increased at the same time as the supply of the nitrogen gas to the central portion of the surface is started, the gas component generated from the surface Wf of the substrate W is surely removed from the gap GP. Can be discharged. As a result, the substrate W can be satisfactorily dried.

In the second embodiment, the execution period of the solid body formation step (step S7) corresponds to an example of the “solid body formation period” of the present invention. Further, the timing of switching from the solid body forming step to the sublimation step corresponds to an example of "after the lapse of the solid body forming period" of the present invention.

FIG. 10 is a timing chart showing operating conditions in the substitution process, the liquid film forming step, and the solidified body forming step in the third embodiment of the substrate processing apparatus according to the present invention. The major difference between the third embodiment and the second embodiment is the supply mode of nitrogen gas in the latter half of the sublimable substance sublimation step (step S6c), and the solid body forming step (step S7) and the sublimation step (step). It is a change in the flow rate of nitrogen gas from the peripheral gas discharge port 67 in S8). Since other configurations and operations are basically the same as those of the second embodiment, the differences will be mainly described here, and the same or corresponding reference numerals will be given and the description thereof will be omitted.

In the second embodiment (FIG. 9), the nitrogen gas discharged from the peripheral gas discharge port 67 is supplied in the latter half of the sublimable substance subsidence step (step S6c). On the other hand, in the third embodiment, as shown in FIG. 10, the discharge of nitrogen gas from the peripheral gas discharge port 67 is temporarily stopped and the discharge of nitrogen gas from the central gas discharge port 66a is temporarily stopped only during the period corresponding to the latter half of the above. Nitrogen gas is discharged to the central portion of the surface of the substrate W. In this way, the nitrogen gas may be temporarily changed from the second supply mode (see the dotted line in FIG. 6A) to the first supply mode (see the alternate long and short dash line in FIG. 6A). Further, nitrogen gas may be discharged from the central gas discharge port 66a to the central portion of the surface of the substrate W while maintaining the discharge of nitrogen gas from the peripheral gas discharge port 67.

Further, in the second embodiment (FIG. 9), the discharge flow rate of nitrogen gas from the peripheral gas discharge port 67 is increased at the timing of switching from the solid body forming step (step S7) to the sublimation step (step S8). In the third embodiment, a large amount of nitrogen gas is discharged in the horizontal direction from the solidified body forming step. That is, in the semi-enclosed space SP, an air flow indicated by a dotted line arrow starting from the peripheral gas discharge port 67 of FIG. 6A is formed during the solidification body forming step. Due to this air flow, the evaporated solvent atmosphere flows toward the spin base 32 without staying above the space SP, so that evaporation is promoted. It is possible to create an environment in which vaporization is likely to occur with respect to a solvent that is particularly difficult to volatilize (low vapor pressure).

As described above, according to the third embodiment, the same effects as those of the first embodiment and the second embodiment can be obtained.

The present invention is not limited to the above-described embodiment, and various modifications can be made other than those described above as long as the present invention is not deviated from the gist thereof. For example, in the above embodiment, the substrate W is rotated at the second rotation speed V2 in the sublimation material subsidence step (step S6c), but the rotation may be stopped.

Further, in the above embodiment, the present invention is applied to an apparatus that executes a spin-off step (step S6b) and a sublimable substance sublimation step (step S6c) in the liquid film forming step (step S6). However, this is not an essential requirement of the present invention, and the present invention can be applied to a device that does not perform both steps or performs one step, for example.

The present invention can be applied to all substrate processing techniques for drying a substrate by utilizing a sublimable substance that changes into a gas without passing through a liquid.

1 ... Processing unit (board processing equipment)
30 ... Spin chuck (board holding part)
31 ... Chuck pin (holding member)
32 ... Spin base (base member)
34 ... Board rotation drive mechanism (rotating part)
50 ... Facing member 51 ... Facing plate 56 ... Facing plate elevating drive mechanism (moving part)
60 ... Central axis nozzle 61 ... Nozzle body 66a ... Central gas discharge port 67 ... Peripheral gas discharge port 513a ... Board facing surface 513b ... Central inclined surface 513c ... Inner peripheral surface 514 ... Engagement member PT ... Pattern SP ... Space V1 ... First 1 rotation speed V2 ... 2nd rotation speed W ... substrate Wf ... surface (of substrate)

Claims (10)

A substrate holding portion having a base member and a plurality of holding members provided on the surface of the base member, and holding the substrate by the plurality of holding members with the surface of the substrate facing upward.
A treatment liquid supply to the surface of the substrate held by the substrate holding portion is supplied with a treatment liquid containing a sublimable substance that changes into a gas without passing through a liquid and a solvent that dissolves in the sublimate substance. Department and
A coagulant forming portion that removes the solvent from the treatment liquid on the surface of the substrate to form a coagulant containing the sublimable substance, and a coagulant forming portion.
A sublimation portion that sublimates the solidified body and removes it from the surface of the substrate,
A first facing surface held by the substrate holding portion that can face the surface of the substrate, and a second facing surface that can face the outer peripheral end of the substrate and the outer peripheral end of the base member held by the substrate holding portion. And the facing member having
A moving portion that moves the facing member relative to the substrate holding portion, and a moving portion.
Equipped with a gas supply unit that supplies inert gas,
During the liquid film forming period in which the treatment liquid is supplied to the surface of the substrate by the treatment liquid supply unit to form the liquid film of the treatment liquid on the surface of the substrate, the moving portion makes the facing member the substrate. The facing member and the base member continue to form a space surrounding the substrate in close proximity to the holding portion.
The gas supply unit is a substrate processing apparatus characterized in that the inert gas is supplied to the space to make the space an inert gas-rich atmosphere. The substrate processing apparatus according to claim 1.
The gas supply unit is a substrate processing device that supplies the inert gas to the space at least at the initial stage of the liquid film formation period. The substrate processing apparatus according to claim 1 or 2.
Further provided with a rotating portion for rotating the substrate held by the substrate holding portion around a rotation axis parallel to the vertical direction.
The treatment liquid supply unit supplies the treatment liquid only at the initial stage of the liquid film formation period.
The rotating part is
At the initial stage of the liquid film formation period, the substrate is rotated at the first rotation speed to spread the treatment liquid over the entire surface of the substrate.
At the end of the liquid film formation period, the sublimating substance is rotated at a second rotation speed lower than the first rotation speed, or the rotation of the substrate is stopped to form a pattern formed on the surface of the substrate. Substrate processing device that sinks. The substrate processing apparatus according to claim 3.
The gas supply unit
A first gas discharge port that discharges the inert gas in parallel with the axis of rotation toward the central portion of the surface of the substrate.
A second gas discharge port that radially discharges the inert gas from the rotating shaft toward the peripheral edge of the surface of the substrate.
A first gas discharge switching unit that switches between the discharge of the inert gas from the first gas discharge port and the stop of the discharge,
A second gas discharge switching unit that switches between the discharge of the inert gas from the second gas discharge port and the stop of the discharge,
Substrate processing equipment with. The substrate processing apparatus according to claim 4.
At the initial stage of the liquid film formation period, the first gas discharge switching unit discharges the inert gas from the first gas discharge port, and the second gas discharge switching unit discharges the inert gas from the second gas discharge port. A substrate processing device that discharges active gas. The substrate processing apparatus according to claim 4 or 5.
In the first half of the sublimation substance sublimation period for sublimating the sublimable substance, the first gas discharge switching unit stops the discharge of the inert gas from the first gas discharge port, and the second gas discharge switching unit stops the discharge of the inert gas. The discharge of the inert gas from the second gas discharge port is stopped, and the discharge is stopped.
In the latter half of the sublimation substance subsidence period, the second gas discharge switching unit continues to stop the discharge of the inert gas, while the first gas discharge switching unit discharges the inert gas from the first gas discharge port. Subsidence processing device to discharge. The substrate processing apparatus according to claim 4 or 5.
During the sublimation substance sublimation period in which the sublimable substance is sublimated, the first gas discharge switching unit stops the discharge of the inert gas from the first gas discharge port, while the second gas discharge switching unit is said. A substrate processing device that discharges the inert gas from the second gas discharge port. The substrate processing apparatus according to claim 4 or 5.
In the first half of the sublimation substance sublimation period for sublimating the sublimable substance, the first gas discharge switching unit stops the discharge of the inert gas from the first gas discharge port, and the second gas discharge switching unit stops the discharge of the inert gas. The inert gas is discharged from the second gas discharge port, and the inert gas is discharged.
In the latter half of the sublimation substance subsidence period, the second gas discharge switching unit stops the discharge of the inert gas from the second gas discharge port, and the first gas discharge switching unit is the first gas discharge port. A substrate processing device that discharges the inert gas from. The substrate processing apparatus according to any one of claims 4 to 8.
During the solid body formation period in which the solid body is formed by the solid body forming unit, the first gas discharge switching unit stops the discharge of the inert gas from the first gas discharge port and switches the second gas discharge. The unit discharges the inert gas from the second gas discharge port.
After the lapse of the solidified body forming period, the first gas discharge switching unit is a substrate processing device that discharges the inert gas from the first gas discharge port. A treatment liquid containing a sublimable substance that changes into a gas without passing through a liquid and a solvent that dissolves in the sublimable substance is supplied to the surface of the substrate held by a plurality of holding members provided on the surface of the base member. A liquid film forming step of forming a liquid film of the treatment liquid on the surface of the substrate, and
A solid body forming step of removing the solvent from the liquid film on the surface of the substrate to form a solid body containing the sublimable substance.
A sublimation step of sublimating the solidified body and removing it from the surface of the substrate is provided.
The liquid film forming step is
The facing member and the facing member and the second facing surface of the facing member are opposed to the outer peripheral end of the base member while the first facing surface of the facing member is opposed to the surface of the substrate held by the plurality of holding members. The process of continuing to form a space surrounding the substrate by the base member, and
The process of supplying the space with an inert gas to make the space rich in the inert gas,
A substrate processing method comprising.

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