JP7513454B2 - SUBSTRATE PROCESSING METHOD AND SUBSTRATE PROCESSING APPARATUS - Google Patents

Description

This invention relates to a substrate processing method and a substrate processing apparatus for processing substrates. Substrates to be processed include, for example, semiconductor wafers, substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks, substrates for photomasks, ceramic substrates, substrates for solar cells, and substrates for FPDs (Flat Panel Displays) such as liquid crystal displays, plasma displays, and organic EL (Electroluminescence) displays.

Hydrofluoric acid is used as an etching solution to etch the surface of the substrate (see Patent Document 1 below). After treating the substrate with the etching solution, the surface of the substrate is rinsed with a rinsing solution such as DIW.

JP 2012-231116 A

In this type of etching process, a large amount of etching solution and rinsing solution mixed with the etching solution is discharged, which places a heavy burden on the environment. Therefore, one object of the present invention is to provide a substrate processing method and substrate processing apparatus that can reduce the amount of etching components used.

One embodiment of the present invention provides a substrate processing method including an etching step of forming a semi-solid coating film containing a first polymer having an etching function and a second polymer having a solid-forming function on the surface of a substrate, and etching a surface layer of the substrate with the first polymer on the substrate, and an etching stop step of curing the second polymer in the coating film by a solid-forming process to change the coating film into a solidified film, thereby stopping the etching of the surface layer of the substrate.

According to this method, a semi-solid coating film containing a first polymer and a second polymer is formed on the surface of the substrate. The surface layer of the substrate is etched by the first polymer in the coating film on the substrate. The second polymer in the coating film is solidified by the solid formation process. This changes the coating film into a solidified film. The first polymer is less likely to diffuse in the solidified film than in the coating film. Therefore, the coating film changes into a solidified film, and etching of the surface layer of the substrate by the first polymer is stopped.

In contrast to this method, in a technique in which a continuous flow of an etching solution such as hydrofluoric acid is continuously supplied toward the surface of the substrate while etching the surface layer of the substrate, the etching solution is continuously discharged outside the substrate.
On the other hand, the fluidity of the semi-solid coating film is lower than that of the continuous flow etching solution, so that the amount of the first polymer discharged outside the substrate, i.e., the consumption of the etching components, can be reduced.

In one embodiment of the present invention, the etching step includes a liquid film etching step of forming a liquid film of a mixed liquid containing the first polymer and the second polymer, and etching a surface layer portion of the substrate with the first polymer in the liquid film of the mixed liquid, and a coating film etching step of forming the coating film from the liquid film of the mixed liquid, and etching a surface layer portion of the substrate with the first polymer in the coating film.
According to this method, not only the surface layer of the substrate is etched by the first polymer in the coating film, but also the surface layer of the substrate is etched by the first polymer in the liquid film of the mixed liquid that is the base of the coating film. The first polymer in the liquid film of the mixed liquid that contacts the surface of the substrate is lost by etching the surface layer of the substrate. The fluidity of the mixed liquid is higher than that of the semi-solid coating film. Therefore, compared to etching by the coating film, when the first polymer near the surface of the substrate is lost by etching, the first polymer in the liquid film is more likely to diffuse so that the concentration of the first polymer in the liquid film that contacts the surface of the substrate is not reduced. Therefore, the reduction in the concentration of the first polymer near the surface of the substrate can be suppressed, and the surface layer of the substrate can be quickly etched.

Furthermore, since etching is performed with a liquid film of the mixed liquid formed on the surface of the substrate, the amount of the first polymer discharged outside the substrate, i.e., the consumption of the etching components, can be reduced compared to a method in which the surface portion of the substrate is etched while a continuous flow of an etching liquid such as hydrofluoric acid is continued to be supplied toward the surface of the substrate.
In one embodiment of the present invention, the liquid film etching step includes a mixed liquid film forming step of ejecting the mixed liquid from a nozzle facing the surface of the substrate toward the surface of the substrate to form a liquid film of the mixed liquid.

According to this method, a mixed solution containing the first polymer and the second polymer in advance is supplied to the surface of the substrate. Since it is not necessary to mix the first polymer and the second polymer on the surface of the substrate, the coating film can be formed quickly. As a result, the time required for substrate processing can be shortened.
In one embodiment of the present invention, the liquid film etching process includes a mixed liquid film formation process of supplying a first polymer liquid containing the first polymer and a second polymer liquid containing the second polymer onto the upper surface of the substrate to form a liquid film of a mixed liquid of the first polymer liquid and the second polymer liquid on the upper surface of the substrate.

According to this method, the first polymer liquid and the second polymer liquid are mixed on the surface of the substrate, so that if the first polymer and the second polymer are reactive with each other, the reaction between the first polymer and the second polymer can be suppressed before the first polymer and the second polymer are supplied to the surface of the substrate.
In one embodiment of the present invention, the mixed liquid forming step includes a step of simultaneously supplying the first polymer liquid to the surface of the substrate and supplying the second polymer liquid to the surface of the substrate. When the first polymer liquid and the second polymer liquid are simultaneously supplied, the time required to form a coating film can be shortened compared to a method in which the first polymer liquid and the second polymer liquid are sequentially supplied to the surface of the substrate. As a result, the time required for substrate processing can be shortened.

In one embodiment of the present invention, the mixed liquid formation process includes a first polymer liquid supplying process of supplying the first polymer liquid toward the surface of the substrate, and after the first polymer liquid supplying process, a second polymer liquid supplying process of supplying the second polymer liquid toward the surface of the substrate to form the mixed liquid on the surface of the substrate.
According to this method, the first polymer liquid is supplied to the surface of the substrate prior to the second polymer liquid. Therefore, a liquid film not containing the second polymer liquid is formed on the surface of the substrate. The concentration of the first polymer in the first polymer liquid is higher than the concentration of the first polymer in the mixed liquid. Therefore, the surface layer of the substrate can be quickly etched by the high concentration first polymer before the mixed liquid is formed.

Furthermore, after the first polymer is consumed to a certain extent as etching progresses, the first polymer liquid and the second polymer liquid are mixed on the surface of the substrate, so that when the first polymer and the second polymer react with each other, the reaction between the first polymer and the second polymer can be further suppressed.
In one embodiment of the present invention, the solid formation process includes a heating process for the coating film, and the second polymer is a thermosetting resin. Therefore, the thermosetting resin as the second polymer in the coating film is hardened by heating. The coating film is changed into a solidified film by the hardening of the thermosetting resin. Since a solidified film is formed by the hardening of the thermosetting resin, the diffusion of the first polymer can be further suppressed. Therefore, etching of the surface layer of the substrate by the first polymer can be more reliably stopped.

In one embodiment of the present invention, the solid formation process includes a light irradiation process on the coating film, and the second polymer is a photocurable resin. Therefore, the photocurable resin as the second polymer in the coating film is cured by irradiation with light. The coating film changes into a solidified film by the curing of the photocurable resin. Since a solidified film is formed by the curing of the photocurable resin, the diffusion of the etching components can be further suppressed. Therefore, etching of the surface layer of the substrate by the etching components can be more reliably stopped.

In one embodiment of the present invention, the substrate processing method further includes a solidified film removal process of peeling the solidified film from the surface of the substrate by supplying a stripping liquid to a surface of the solidified film, thereby removing the solidified film from the surface of the substrate.
When the surface layer of the substrate is etched using the first polymer in the coating film, etching residues are likely to adhere to the surface of the substrate. Therefore, if the solidified film is not dissolved in a stripping solution and removed from the surface of the substrate in the solidified film removal step, but is peeled off from the surface of the substrate, the solidified film is peeled off from the surface of the substrate while retaining the etching residues. As a result, the etching residues can be removed from the surface of the substrate together with the solidified film.

In one embodiment of the present invention, the solidified film is formed in the etching stopping step, the solidified film containing a soluble component having a higher solubility in the stripping solution than the second polymer, and the soluble component in the solidified film is dissolved by the stripping solution supplied in the solidified film removing step.
According to this method, the solidified film contains a soluble component. The soluble component in the solidified film is dissolved by the stripping liquid that is then supplied to the surface of the substrate. By dissolving the soluble component in the solidified film with the stripping liquid, a gap (through hole) is formed in the solidified film. Therefore, the stripping liquid can be made to quickly reach the interface between the solidified film and the substrate through the through hole formed in the solidified film. The stripping liquid enters the interface between the substrate and the solidified film and strips the solidified film from the surface of the substrate. This allows the solidified film to be quickly stripped from the surface of the substrate after etching with the first polymer is completed.

In one embodiment of the present invention, in the etching step, an etching residue is formed by etching a surface portion of the substrate. The etching residue is held by the solidified film formed in the etching stopping step. The solidified film removal step includes a step of removing the etching residue together with the solidified film while the etching residue is held by the solidified film.

According to this method, the etching residues generated by etching the surface layer of the substrate are removed from the surface of the substrate together with the solidified film in the solidified film removal step, so that there is no need to carry out a separate process for removing the etching residues after removing the solidified film.
Another embodiment of the present invention provides a substrate processing apparatus including a coating film forming unit that forms a coating film on a surface of a substrate, the coating film containing a first polymer having an etching function and a second polymer having a solid-forming function; a solid formation unit that performs a solid formation process of solidifying or hardening the second polymer in the coating film on the surface of the substrate to form a solidified film; a stripping liquid supply unit that supplies a stripping liquid toward the surface of the substrate to strip the solidified film from the surface of the substrate; and a controller that controls the coating film forming unit, the solid formation unit, and the stripping liquid supply unit.

In this substrate processing apparatus, the controller is programmed to execute an etching process in which the coating film is formed on the surface of the substrate by the coating film forming unit and the surface portion of the substrate is etched by the first polymer in the coating film, an etching stop process in which the etching of the surface portion of the substrate is stopped by hardening the second polymer in the coating film by the solid formation process by the solid formation unit to change the coating film into a solidified film, and a solidified film removal process in which the solidified film is peeled off from the surface of the substrate by supplying a peeling liquid to the surface of the solidified film, thereby removing the solidified film from the surface of the substrate.

This device achieves the same effects as the substrate processing method described above.

FIG. 1 is a schematic plan view showing the layout of a substrate processing apparatus according to a first embodiment of the present invention. FIG. 2 is a schematic partial cross-sectional view showing a schematic configuration of a processing unit provided in the substrate processing apparatus. FIG. 3 is a block diagram showing the electrical configuration of the main parts of the substrate processing apparatus. FIG. 4 is a flow chart for explaining an example of substrate processing by the substrate processing apparatus. FIG. 5A is a schematic diagram for explaining the mixed liquid supplying step (step S2) of the substrate processing. FIG. 5B is a schematic diagram for explaining the coating film forming step (step S3) of the substrate processing. FIG. 5C is a schematic diagram for explaining the solidified film forming step (step S4) of the substrate processing. FIG. 5D is a schematic diagram for explaining the solidified film removing step (step S5) of the substrate processing. FIG. 5E is a schematic diagram for explaining the solidified film removing step (step S5) of the substrate processing. FIG. 5F is a schematic diagram for explaining the rinse step (step S6) of the substrate processing. FIG. 6A is a schematic diagram for explaining the state near the surface of the substrate during the substrate processing. FIG. 6B is a schematic diagram for explaining the state near the surface of the substrate during the substrate processing. FIG. 6C is a schematic diagram for explaining the state near the surface of the substrate during the substrate processing. FIG. 6D is a schematic diagram for explaining the state near the surface of the substrate during the substrate processing. FIG. 6E is a schematic diagram for explaining the state near the surface of the substrate during the substrate processing. FIG. 7 is a schematic partial cross-sectional view showing a schematic configuration of a processing unit provided in a substrate processing apparatus according to the second embodiment. FIG. 8 is a schematic view for explaining a first example of the mixed liquid supplying step (step S2) in the substrate processing by the substrate processing apparatus according to the second embodiment. FIG. 9A is a schematic view for explaining a second example of the mixed liquid supplying step (step S2) in the substrate processing by the substrate processing apparatus according to the second embodiment. FIG. 9B is a schematic view for explaining a second example of the mixed liquid supplying step (step S2) in the substrate processing by the substrate processing apparatus according to the second embodiment. FIG. 10 is a schematic view showing a schematic configuration of a processing unit provided in a substrate processing apparatus according to the third embodiment. FIG. 11 is a schematic view for explaining an example of the solidified film forming step (step S4) in the substrate processing by the substrate processing apparatus according to the third embodiment. FIG. 12 is a schematic diagram for explaining the state near the surface of the substrate during the solidified film forming process (step S4) of the substrate processing according to the third embodiment. FIG. 13 is a schematic view for explaining a modified example of the substrate processing apparatus according to the third embodiment. FIG. 14 is a schematic diagram for explaining a first modified example of the light irradiation unit provided in the processing unit according to the third embodiment. FIG. 15 is a schematic diagram for explaining a second modified example of the light irradiation unit provided in the processing unit according to the third embodiment. FIG. 16 is a schematic view for explaining the configuration of a substrate processing apparatus according to a fourth embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
First Embodiment
FIG. 1 is a schematic plan view showing a layout of a substrate processing apparatus 1 according to one embodiment of the present invention.
The substrate processing apparatus 1 is a single-wafer type apparatus that processes substrates W such as silicon wafers one by one. In this embodiment, the substrate W is a disk-shaped substrate. As the substrate W, a substrate having an etchable component exposed on the surface can be used. As the substrate W, a substrate having at least one of SiO ₂ (silicon oxide), TiN (titanium nitride), Cu (copper), Ru (ruthenium), Co (cobalt), Mo (molybdenum) and W (tungsten) exposed on the surface is preferably used. Only one of the above-mentioned substances may be exposed on the surface of the substrate W, or a plurality of the above-mentioned substances may be exposed on the surface of the substrate W.

The substrate processing apparatus 1 includes a plurality of processing units 2 that process substrates W with a fluid, a load port LP on which a carrier C that accommodates a plurality of substrates W to be processed in the processing units 2 is placed, transport robots IR and CR that transport the substrates W between the load port LP and the processing units 2, and a controller 3 that controls the substrate processing apparatus 1.
The transport robot IR transports the substrate W between the carrier C and the transport robot CR. The transport robot CR transports the substrate W between the transport robot IR and the processing units 2. The processing units 2 have, for example, the same configuration. Although described in detail below, the fluids supplied to the substrate W in the processing units 2 include a mixed liquid, a first polymer liquid, a second polymer liquid, a stripping liquid, a rinsing liquid, etc.

Each processing unit 2 includes a chamber 4 and a processing cup 7 disposed in the chamber 4, and performs processing on the substrate W in the processing cup 7. The chamber 4 is formed with an entrance (not shown) through which the transport robot CR loads and unloads the substrate W. The chamber 4 is provided with a shutter unit (not shown) that opens and closes this entrance.

2 is a schematic diagram for explaining an example of the configuration of the processing unit 2. The processing unit 2 further includes a spin chuck 5, a heater unit 6, a first moving nozzle 9, a second moving nozzle 10, and a third moving nozzle 11.
The spin chuck 5 is an example of a substrate holding and rotating unit that rotates the substrate W about a rotation axis A1 (vertical axis) while holding the substrate W horizontally. The rotation axis A1 is a vertical line passing through the center of the substrate W. The spin chuck 5 includes a plurality of chuck pins 20, a spin base 21, a rotation shaft 22, and a spin motor 23.

The spin base 21 has a horizontally extending disk shape. On the upper surface of the spin base 21, a plurality of chuck pins 20 for gripping the peripheral edge of the substrate W are arranged at intervals in the circumferential direction of the spin base 21.
The multiple chuck pins 20 are opened and closed by a pin opening and closing unit 24. The multiple chuck pins 20 horizontally hold (clamp) the substrate W when closed by the pin opening and closing unit 24. The multiple chuck pins 20 release the substrate W when opened by the pin opening and closing unit 24. In the open state, the multiple chuck pins 20 support the substrate W from below.

The spin base 21 and the plurality of chuck pins 20 constitute a substrate holding unit that horizontally holds the substrate W. The substrate holding unit is also called a substrate holder.
The rotation shaft 22 extends vertically along the rotation axis A1. The upper end of the rotation shaft 22 is coupled to the center of the lower surface of the spin base 21. The spin motor 23 applies a rotational force to the rotation shaft 22. The rotation shaft 22 is rotated by the spin motor 23, thereby rotating the spin base 21. As a result, the substrate W is rotated about the rotation axis A1. The spin motor 23 is an example of a substrate rotation unit that rotates the substrate W about the rotation axis A1.

The heater unit 6 is an example of a substrate heating unit that heats the entire substrate W. The heater unit 6 has the form of a disk-shaped hot plate. The heater unit 6 is disposed between the upper surface of the spin base 21 and the lower surface of the substrate W. The heater unit 6 has an opposing surface 6a that faces the lower surface of the substrate W from below.
The heater unit 6 includes a plate body 61 and a heater 62. The plate body 61 is slightly smaller than the substrate W in a plan view. The upper surface of the plate body 61 constitutes the facing surface 6a. The heater 62 may be a resistor built into the plate body 61. The facing surface 6a is heated by passing electricity through the heater 62. The facing surface 6a is heated to, for example, 195°C.

The processing unit 2 includes a heater energizing unit 64 that supplies power to the heater 62 via a power supply line 63, and a heater lifting unit 65 that raises and lowers the heater unit 6 relative to the spin base 21. The heater energizing unit 64 is, for example, a power source. The heater lifting unit 65 includes, for example, a ball screw mechanism (not shown) and an electric motor (not shown) that provides driving force to the ball screw mechanism. The heater lifting unit 65 is also called a heater lifter.

An elevation shaft 66 extending vertically along the rotation axis A1 is coupled to the lower surface of the heater unit 6. The elevation shaft 66 passes through a through hole 21a formed in the center of the spin base 21 and the hollow rotation shaft 22. A power supply line 63 passes through the interior of the elevation shaft 66.
The heater lifting unit 65 lifts and lowers the heater unit 6 via the lifting shaft 66. The heater unit 6 can be positioned at a lower position and an upper position by being lifted and lowered by the heater lifting unit 65. The heater lifting unit 65 can position the heater unit 6 not only at the lower position and the upper position, but also at any position between the lower position and the upper position.

When the heater unit 6 is raised, it can receive the substrate W from the multiple chuck pins 20 in the open state. The heater unit 6 can heat the substrate W by being positioned by the heater lifting unit 65 at a position in contact with the lower surface of the substrate W or in close proximity to the lower surface of the substrate W.
The processing cup 7 includes a plurality of guards 71 for receiving liquid that splashes outward from the substrate W held on the spin chuck 5, a plurality of cups 72 for receiving liquid guided downward by the multiple guards 71, and a cylindrical outer wall member 73 that surrounds the multiple guards 71 and the multiple cups 72.

In this embodiment, an example is shown in which two guards 71 (a first guard 71A and a second guard 71B) and two cups 72 (a first cup 72A and a second cup 72B) are provided.
Each of the first cup 72A and the second cup 72B has the form of an upwardly opening annular groove.

The first guard 71A is disposed so as to surround the spin base 21. The second guard 71B is disposed so as to surround the spin base 21 on the outer side of the first guard 71A.
The first guard 71A and the second guard 71B each have a substantially cylindrical shape. The upper end of each guard 71 is inclined inward toward the spin base 21.

The first cup 72A receives the liquid guided downward by the first guard 71 A. The second cup 72B is formed integrally with the first guard 71 A, and receives the liquid guided downward by the second guard 71B.
The processing unit 2 includes a guard lifting unit 74 that vertically raises and lowers the first guard 71A and the second guard 71B separately. The guard lifting unit 74 raises and lowers the first guard 71A between a lower position and an upper position. The guard lifting unit 74 raises and lowers the second guard 71B between a lower position and an upper position.

When the first guard 71A and the second guard 71B are both in the upper position, liquid splashed from the substrate W is received by the first guard 71A. When the first guard 71A is in the lower position and the second guard 71B is in the upper position, liquid splashed from the substrate W is received by the second guard 71B. When the first guard 71A and the second guard 71B are both in the lower position, the transport robot CR can access the spin chuck 5 to load and unload the substrate W.

The guard lifting unit 74 includes, for example, a first ball screw mechanism (not shown) coupled to the first guard 71A, a first motor (not shown) that provides a driving force to the first ball screw mechanism, a second ball screw mechanism (not shown) coupled to the second guard 71B, and a second motor (not shown) that provides a driving force to the second ball screw mechanism. The guard lifting unit 74 is also called a guard lifter.

The first movable nozzle 9 is an example of a mixed liquid nozzle (mixed liquid supply unit) that supplies (discharges) a mixed liquid containing a first polymer and a second polymer toward the upper surface of the substrate W held by the spin chuck 5.
The first movable nozzle 9 is moved in the horizontal and vertical directions by the first nozzle movement unit 35. The first movable nozzle 9 can move in the horizontal direction between a central position and a home position (retracted position). When the first movable nozzle 9 is located at the central position, it faces a central region of the upper surface of the substrate W.

When the first moving nozzle 9 is located at the home position, it does not face the upper surface of the substrate W and is located outside the processing cup 7 in a plan view. The first moving nozzle 9 can approach the upper surface of the substrate W or retreat upward from the upper surface of the substrate W by moving in the vertical direction.
The first nozzle moving unit 35 may include an arm (not shown) connected to the first moving nozzle 9 and extending horizontally, a rotating shaft (not shown) connected to the arm and extending vertically, and a rotating shaft drive unit (not shown) that raises and lowers and rotates the rotating shaft.

The pivot drive unit swings the arm by rotating the pivot about a vertical pivot axis. Furthermore, the pivot drive unit raises and lowers the arm by raising and lowering the pivot along the vertical direction. In response to the swinging and raising and lowering of the arm, the first moving nozzle 9 moves in the horizontal and vertical directions.
The first moving nozzle 9 is connected to a mixed liquid pipe 40 that guides the mixed liquid to the first moving nozzle 9. When a mixed liquid valve 50 disposed in the mixed liquid pipe 40 is opened, the mixed liquid is discharged in a continuous flow downward from the discharge port of the first moving nozzle 9. When the mixed liquid valve 50 is opened while the first moving nozzle 9 is located at the central position, the mixed liquid is supplied to the central region of the upper surface of the substrate W.

The mixture contains a solute and a solvent. The solvent contained in the mixture is, for example, an organic solvent.
Examples of the organic solvent include alcohols such as isopropanol (IPA), ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate, propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether (PGME) and propylene glycol monoethyl ether (PGEE), propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monoethyl ether acetate, lactic acid esters such as methyl lactate and ethyl lactate (EL), aromatic hydrocarbons such as toluene and xylene, ketones such as methyl ethyl ketone, 2-heptanone, and cyclohexanone, amides such as N,N-dimethylacetamide and N-methylpyrrolidone, and lactones such as γ-butyrolactone. These organic solvents can be used alone or in combination of two or more.

The mixed liquid contains a first polymer, a second polymer, and a dissolved component as solutes. The first polymer is a component capable of etching the surface layer of the substrate W, i.e., a component having an etching function. The first polymer is, for example, an organic acid polymer such as a carboxylic acid or a sulfonic acid. An example of the carboxylic acid is polyacrylic acid, as shown in the following chemical formula 1. An example of the sulfonic acid is polystyrene sulfonic acid, as shown in the following chemical formula 2.

The second polymer is a component that solidifies or hardens by a solid-forming process such as heating or light irradiation, i.e., a component that has a solid-forming function. In the first embodiment, the second polymer is a thermosetting resin that hardens by heating. The thermosetting resin may include, for example, at least one of an epoxy resin, a phenolic resin, a melamine resin, an unsaturated polyester resin, and a polyurethane resin.

The soluble component is a substance that is more soluble in the stripping solution described below than the second polymer. An example of the soluble component is 2,2-bis(4-hydroxyphenyl)propane. The soluble component is not limited to 2,2-bis(4-hydroxyphenyl)propane. Details of the soluble component will be described later.
The second moving nozzle 10 is an example of a stripping liquid nozzle (stripping liquid supply unit) that supplies (discharges) a continuous flow of a stripping liquid such as ammonia water toward the upper surface of the substrate W held by the spin chuck 5. The stripping liquid is a liquid for stripping a solidified film formed on the substrate W from the upper surface of the substrate W.

The second movable nozzle 10 is moved in the horizontal and vertical directions by the second nozzle movement unit 36. The second movable nozzle 10 can move in the horizontal direction between a central position and a home position (retracted position).
When the second moving nozzle 10 is located at the central position, it faces a central region of the upper surface of the substrate W. When the second moving nozzle 10 is located at the home position, it does not face the upper surface of the substrate W and is located outside the processing cup 7 in a plan view. The second moving nozzle 10 can approach the upper surface of the substrate W or retreat upward from the upper surface of the substrate W by moving in the vertical direction.

The second nozzle moving unit 36 has a configuration similar to that of the first nozzle moving unit 35. That is, the second nozzle moving unit 36 may include an arm (not shown) connected to the second moving nozzle 10 and extending horizontally, a rotating shaft (not shown) connected to the arm and extending vertically, and a rotating shaft drive unit (not shown) that raises and lowers and rotates the rotating shaft.

The second moving nozzle 10 is connected to a stripping liquid pipe 41 that guides the stripping liquid to the second moving nozzle 10. When a stripping liquid valve 51 interposed in the stripping liquid pipe 41 is opened, the stripping liquid is ejected downward in a continuous flow from the outlet of the second moving nozzle 10. When the stripping liquid valve 51 is opened while the second moving nozzle 10 is located at the central position, the stripping liquid is supplied to the central region of the upper surface of the substrate W.

The stripping liquid discharged from the second moving nozzle 10 is a liquid that dissolves soluble components more easily than solid-forming components. The stripping liquid discharged from the second moving nozzle 10 is, for example, an alkaline aqueous solution (alkaline liquid) such as ammonia water. Specific examples of alkaline aqueous solutions include ammonia water, SC1 liquid (ammonia-hydrogen peroxide mixture), TMAH (tetramethylammonium hydroxide) aqueous solution, and choline aqueous solution, as well as any combination of these. The stripping liquid is not limited to an alkaline liquid, and may be pure water (preferably DIW) or either a neutral or acidic aqueous solution (non-alkaline aqueous solution).

The third moving nozzle 11 is an example of a rinsing liquid nozzle (rinsing liquid supply unit) that supplies (discharges) a continuous flow of a rinsing liquid such as pure water toward the upper surface of the substrate W held by the spin chuck 5. The rinsing liquid is a liquid that washes away liquid adhering to the surface of the substrate W.
The third movable nozzle 11 is moved in the horizontal and vertical directions by the third nozzle movement unit 37. The third movable nozzle 11 can move in the horizontal direction between a central position and a home position (retracted position).

When the third moving nozzle 11 is located at the central position, it faces a central region of the upper surface of the substrate W. When the third moving nozzle 11 is located at the home position, it does not face the upper surface of the substrate W and is located outside the processing cup 7 in a plan view. The third moving nozzle 11 can approach the upper surface of the substrate W or retreat upward from the upper surface of the substrate W by moving in the vertical direction.
The third nozzle moving unit 37 has a configuration similar to that of the first nozzle moving unit 35. That is, the third nozzle moving unit 37 may include an arm (not shown) connected to the third moving nozzle 11 and extending horizontally, a rotating shaft (not shown) connected to the arm and extending along the vertical direction, and a rotating shaft drive unit (not shown) that raises and lowers and rotates the rotating shaft.

The third moving nozzle 11 is connected to a rinsing liquid pipe 42 that guides rinsing liquid to the third moving nozzle 11. When a rinsing liquid valve 52 disposed in the rinsing liquid pipe 42 is opened, the rinsing liquid is ejected downward in a continuous flow from the ejection port of the third moving nozzle 11. When the rinsing liquid valve 52 is opened while the third moving nozzle 11 is positioned at the central position, the rinsing liquid is supplied to the central region of the upper surface of the substrate W.

Examples of the rinse liquid include pure water such as DIW, carbonated water, electrolytic ion water, diluted hydrochloric acid water (for example, about 1 ppm to 100 ppm), diluted ammonia water (for example, about 1 ppm to 100 ppm), reduced water (hydrogen water), and the like.
An organic solvent such as IPA can be used as the rinse liquid as long as it is compatible with the stripping liquid. Compatibility refers to the property of two types of liquids dissolving and mixing with each other. In the substrate processing described below, the rinse liquid on the substrate W is shaken off to dry the upper surface of the substrate W, and if the rinse liquid is a low surface tension liquid, the surface tension acting on the upper surface of the substrate W when the upper surface of the substrate W is dried can be reduced.

Examples of organic solvents that function as low surface tension liquids include liquids containing at least one of IPA, HFE (hydrofluoroether), methanol, ethanol, acetone, PGEE (propylene glycol monoethyl ether), and trans-1,2-dichloroethylene.
The organic solvent functioning as a low surface tension liquid does not need to be composed of a single component, but may be a liquid mixed with other components, for example, a mixture of IPA and DIW, or a mixture of IPA and HFE.

3 is a block diagram showing an electrical configuration of the main parts of the substrate processing apparatus 1. The controller 3 includes a microcomputer, and controls the controlled objects provided in the substrate processing apparatus 1 according to a predetermined control program.
Specifically, the controller 3 includes a processor (CPU) 3A and a memory 3B in which a control program is stored. The controller 3 is configured to execute various controls for substrate processing by the processor 3A executing the control program.

In particular, the controller 3 is programmed to control the transport robots IR and CR, the spin motor 23, the pin opening and closing unit 24, the first nozzle moving unit 35, the second nozzle moving unit 36, the third nozzle moving unit 37, the heater energizing unit 64, the heater lifting unit 65, the guard lifting unit 74, the mixed liquid valve 50, the stripping liquid valve 51, and the rinsing liquid valve 52. By controlling the valves with the controller 3, it is possible to control whether or not processing fluid is discharged from the corresponding nozzle, and the flow rate of processing fluid discharged from the corresponding nozzle.

Fig. 4 is a flow chart for explaining an example of substrate processing by the substrate processing apparatus 1. Fig. 4 mainly shows processing that is realized by the controller 3 executing a program. Figs. 5A to 5E are schematic diagrams for explaining the state of each step of the substrate processing.
In substrate processing by the substrate processing apparatus 1, for example, as shown in FIG. 4, a substrate loading step (step S1), a mixed liquid supply step (step S2), a coating film forming step (step S3), a solidified film forming step (step S4), a solidified film removing step (step S5), a rinsing step (step S6), a spin drying step (step S7), and a substrate unloading step (step S8) are performed in this order.

In the following, reference will be made mainly to Figures 2 and 4. Reference will also be made to Figures 5A to 5E as appropriate.
First, an unprocessed substrate W is carried from the carrier C into the processing unit 2 by the transport robots IR and CR (see FIG. 1) and handed over to the spin chuck 5 (step S1). As a result, the substrate W is held horizontally by the spin chuck 5 (substrate holding step).
When the substrate W is loaded, the heater unit 6 is disposed in a non-heating position where the heater 62 is energized and the substrate W is not heated. The non-heating position is, for example, the lower position. Unlike this substrate processing, the heater unit 6 may switch between heating and stopping the heating of the substrate W depending on whether the heater energizing unit 64 is energized or not.

The spin chuck 5 continues to hold the substrate W until the spin dry process (step S7) is completed. From the start of the substrate holding process until the end of the spin dry process (step S7), the guard lifting unit 74 adjusts the height positions of the first guard 71A and the second guard 71B so that at least one guard 71 is located in the upper position. With the substrate W held by the spin chuck 5, the spin motor 23 rotates the spin base 21. This starts the rotation of the substrate W held horizontally (substrate rotation process).

Next, after the transport robot CR retreats to the outside of the processing unit 2, a mixed liquid supplying step (step S2) is performed in which the mixed liquid is supplied to the upper surface of the substrate W. Specifically, the first nozzle moving unit 35 moves the first moving nozzle 9 to a processing position. The processing position of the first moving nozzle 9 is, for example, a central position.
With the first moving nozzle 9 in the processing position, the mixed liquid valve 50 is opened. As a result, as shown in Fig. 5A, the mixed liquid is supplied (discharged) from the first moving nozzle 9 toward the central region of the upper surface of the rotating substrate W (mixed liquid supplying step, mixed liquid discharging step). The mixed liquid supplied to the upper surface of the substrate W spreads over the entire upper surface of the substrate W by centrifugal force, and a liquid film 101 of the mixed liquid is formed over the entire upper surface of the substrate W (mixed liquid film forming step). The surface layer of the substrate W is etched by the first polymer (organic acid polymer) in the liquid film 101 of the mixed liquid (etching step, liquid film etching step).

The supply of the mixed liquid from the first moving nozzle 9 continues for a predetermined time, for example, 2 to 4 seconds. In the mixed liquid supplying step, the substrate W is rotated at a predetermined mixed liquid rotation speed, for example, 10 to 1500 rpm. The amount of the mixed liquid applied to the upper surface of the substrate W is about 2 cc.
The rotation speed of the mixed liquid is preferably a speed at which the mixed liquid does not scatter outward from the substrate W, and it is preferable that a liquid film 101 of the mixed liquid is in a puddle state on the substrate W. The puddle state means a state in which the upper surface of the substrate W is covered with the liquid film 101 and the substrate W is stationary in the rotation direction or rotating at a low rotation speed (50 rpm or less).

Next, as shown in FIG. 5B, a coating film forming step (step S3) is performed in which the solvent is evaporated from the mixed liquid on the substrate W to form a coating film 102.
Specifically, the mixed liquid valve 50 is closed. Then, the first nozzle moving unit 35 moves the first moving nozzle 9 to the home position.
The centrifugal force caused by the rotation of the substrate W acts not only on the mixed liquid on the substrate W but also on the gas in contact with the liquid film 101. Therefore, the centrifugal force forms an airflow in which the gas flows from the center side of the substrate W to the periphery side. This airflow removes the gaseous solvent in contact with the liquid film 101 from the atmosphere in contact with the substrate W. Therefore, evaporation (volatilization) of the solvent from the mixed liquid on the substrate W is promoted, and a semi-solid coating film 102 is formed (coating film forming process). The semi-solid state refers to a state in which a solid component and a liquid component are mixed. The first moving nozzle 9 and the spin motor 23 are an example of a coating film forming unit.

The surface layer of the substrate W is etched by the first polymer (organic acid polymer) in the coating film 102 (etching process). The coating film 102 has a higher viscosity than the liquid film 101. In the coating film forming process, the spin motor 23 functions as an evaporation unit (evaporation promotion unit) that evaporates the solvent in the mixed liquid.
The coating film forming step (step S3) continues for, for example, 30 seconds. In the coating film forming step (step S3), the substrate W is rotated at a predetermined coating film forming speed, for example, 800 rpm.

Next, a solidified film forming step (step S4) is performed in which the coating film 102 on the substrate W is hardened to form the solidified film 100.
Specifically, the heater lifting unit 65 places the heater unit 6 at a heating position. The heating position is, for example, a remote heating position where the substrate W is heated at a position remote from the lower surface of the substrate W. As a result, the coating film 102 is heated by the heater unit 6 through the substrate W (coating film heating step), as shown in FIG.

Heating the coating film 102 hardens the second polymer (thermosetting resin) in the coating film 102. The hardening of the second polymer forms a solidified film 100 (solidified film formation process). Heating hardens the second polymer in the coating film 102, changing the coating film 102 into a solidified film 100, thereby stopping the etching of the surface layer of the substrate W (etching stop process). Since the solidified film 100 is formed by heating, heating is an example of a solid formation process. The heater unit 6 is an example of a solid formation unit.

Heating of the coating film 102 is continued for a predetermined time, for example, 30 seconds. In the solidified film forming step (step S4), the substrate W is rotated at a predetermined solidified film forming speed, for example, 800 rpm.
Next, as shown in FIGS. 5D and 5E, a stripping liquid is supplied to the upper surface of the substrate W to perform a solidified film removing step (step S5) of stripping and removing the solidified film 100 from the upper surface of the substrate W.

Specifically, the heater lifting unit 65 moves the heater unit 6 to a non-heating position. Then, the second nozzle moving unit 36 moves the second moving nozzle 10 to a processing position. The processing position of the second moving nozzle 10 is, for example, the central position.
With the second moving nozzle 10 positioned at the processing position, the stripping liquid valve 51 is opened. As a result, as shown in FIG. 5D, the stripping liquid is supplied (discharged) from the second moving nozzle 10 toward the central region of the upper surface of the rotating substrate W (stripping liquid supplying process, stripping liquid discharging process). The stripping liquid supplied to the upper surface of the substrate W spreads over the entire substrate W by centrifugal force. The stripping liquid supplied to the upper surface of the substrate W reaches the interface between the upper surface of the substrate W and the solidified film 100 while dissolving the soluble components in the solidified film 100, and penetrates between the solidified film 100 and the upper surface of the substrate W. As shown in FIG. 5E, the supply of the stripping liquid is continued, and the solidified film 100 is stripped and removed from the upper surface of the substrate W (solidified film removing process).

The supply of the stripping liquid is continued for, for example, 30 seconds. In the solidified film removing step (step S5), the substrate W is rotated at a predetermined removal rotation speed, for example, 800 rpm.
5F, a rinsing process (step S6) is performed to rinse the stripping liquid from the upper surface of the substrate W. Specifically, the stripping liquid valve 51 is closed, and the second nozzle movement unit 36 moves the second moving nozzle 10 to the retracted position. Then, the third nozzle movement unit 37 moves the third moving nozzle 11 to the processing position. The processing position of the third moving nozzle 11 is, for example, the central position.

Then, with the third moving nozzle 11 in the processing position, the rinsing liquid valve 52 is opened. As a result, as shown in FIG. 5F, rinsing liquid is supplied (discharged) from the third moving nozzle 11 toward the central region of the upper surface of the rotating substrate W (rinsing liquid supply process, rinsing liquid discharge process). The rinsing liquid supplied to the upper surface of the substrate W spreads over the entire upper surface of the substrate W due to centrifugal force. As a result, the stripping liquid adhering to the upper surface of the substrate W is discharged outside the substrate W together with the rinsing liquid and replaced with the rinsing liquid (rinsing process, stripping liquid discharge process).

The supply of the rinsing liquid to the upper and lower surfaces of the substrate W continues for a predetermined time, for example, 30 seconds. In the rinsing step (step S6), the substrate W is rotated at a predetermined rinsing rotation speed, for example, 800 rpm.
Next, a spin dry process (step S7) is performed in which the substrate W is rotated at high speed to dry the upper surface of the substrate W. Specifically, the rinse liquid valve 52 is closed. This stops the supply of the rinse liquid to the upper surface of the substrate W.

Then, the spin motor 23 accelerates the rotation of the substrate W, rotating it at high speed. In the spin dry process, the substrate W is rotated at a drying speed, for example, 1500 rpm. The spin dry process is performed for a predetermined time, for example, 30 seconds. As a result, a large centrifugal force acts on the rinsing liquid on the substrate W, and the rinsing liquid on the substrate W is scattered around the substrate W.

Then, the spin motor 23 stops the rotation of the substrate W. The guard lifting unit 74 moves the first guard 71A and the second guard 71B to the lower position.
The transport robot CR enters the processing unit 2, scoops up the processed substrate W from the chuck pins 20 of the spin chuck 5, and carries it out of the processing unit 2 (step S8). The substrate W is handed over from the transport robot CR to the transport robot IR, and is stored in the carrier C by the transport robot IR.

Next, the state of the vicinity of the surface of the substrate W during substrate processing will be described in detail with reference to Figures 6A to 6E. Figures 6A to 6E are schematic diagrams for explaining the state of the vicinity of the surface of the substrate W during substrate processing.
The coating film 102 formed in the coating film forming step (step S3) contains a first polymer (organic acid polymer), a second polymer (thermosetting resin) and a soluble component. The first polymer in the coating film 102 etches a surface layer 150 of the substrate W (etching step). The surface layer 150 of the substrate W refers to a portion in the vicinity of the surface of the substrate W.

The first polymer in the coating film 102 in contact with the upper surface 151 of the substrate W disappears by etching the surface layer 150 of the substrate W. Therefore, the first polymer in the coating film 102 moves toward the upper surface 151 of the substrate W so that the concentration of the first polymer in the coating film 102 in contact with the upper surface 151 of the substrate W does not decrease. Therefore, as shown in FIG. 6B, etching of the surface layer 150 of the substrate W gradually progresses, and the upper surface 151 of the substrate W retreats toward the lower surface of the substrate W. Etching of the surface layer 150 of the substrate W forms etching residue 104.

Then, the coating film 102 is heated through the substrate W, and as shown in FIG. 6C, the coating film 102 changes into a solidified film 100. The solidified film 100 contains a first polymer, a second polymer, and a dissolved component in a solid state. The first polymer in a solid state is called a first polymer solid 110. The second polymer in a solid state is called a second polymer solid 111. The dissolved component in a solid state is called a dissolved component solid 112. The solidified film 100 (particularly the second polymer solid 111) retains the etching residue 104 formed by the etching process.

6D, the dissolving component solid 112 is selectively dissolved by the stripping solution. That is, the solidified film 100 is partially dissolved (dissolving step, partial dissolving step).
The phrase "the soluble component solid 112 in the solid state is selectively dissolved" does not mean that only the soluble component solid 112 in the solid state is dissolved. The phrase "the soluble component solid 112 in the solid state is selectively dissolved" means that the second polymer solid 111 in the solid state is also slightly dissolved, but most of the soluble component solid 112 in the solid state is dissolved.

The selective dissolution of the dissolved component solid 112 triggers the formation of the through-holes 106 in the portion of the solidified film 100 where the dissolved component solid 112 is unevenly distributed (through-hole forming step).
In the portion where the dissolved component solid 112 is unevenly distributed, not only the dissolved component solid 112 but also the second polymer solid 111 is present. The stripping solution dissolves not only the dissolved component solid 112 but also the second polymer solid 111 around the dissolved component solid 112, and thus the formation of the through-hole 106 is promoted.

The through-hole 106 has a diameter of, for example, several nm in plan view. The through-hole 106 does not need to be clearly formed to an observable extent. In other words, the through-hole 106 only needs to be a path formed in the solidified film 100 for moving the stripping liquid from the upper surface of the solidified film 100 to the upper surface of the substrate, and the path only needs to penetrate the solidified film 100 as a whole.
Here, when an appropriate amount of solvent remains in the solidified film 100, the remover liquid dissolves into the solvent remaining in the solidified film 100 and partially dissolves the solidified film 100. More specifically, the remover liquid dissolves into the solvent remaining in the solidified film 100 and dissolves the soluble component solid 112 in the solidified film 100 to form the through-holes 106. Therefore, the remover liquid easily penetrates into the solidified film 100 (dissolving and penetrating process).

The remover liquid that has reached the upper surface 151 of the substrate W acts on the interface between the solidified film 100 and the substrate W to remove the solidified film 100, and removes the removed solidified film 100 from the upper surface 151 of the substrate W (removal and removal process).
More specifically, the solubility of the second polymer solid 111 in the stripping solution is lower than that of the soluble component solid 112 in the stripping solution, and most of the second polymer solid 111 remains in a solid state. Therefore, the second polymer solid 111 is only slightly dissolved near its surface by the stripping solution. Therefore, the stripping solution that has reached the vicinity of the upper surface 151 of the substrate W via the through-hole 106 slightly dissolves the portion of the second polymer solid 111 near the upper surface 151 of the substrate W. As a result, as shown in the enlarged view of FIG. 6D , the stripping solution gradually dissolves the second polymer solid 111 in a solid state near the upper surface 151 of the substrate W, and enters the gap G between the solidified film 100 and the upper surface 151 of the substrate W (stripping solution entry step).

Then, for example, a crack is formed in the solidified film 100 starting from the periphery of the through hole 106. Therefore, the dissolved component solid 112 is also called a crack generating component. The solidified film 100 splits due to the formation of the crack, and becomes film pieces 108. As shown in FIG. 6E, the film pieces 108 of the solidified film 100 are peeled off from the substrate W while still holding the etching residue 104 (solidified film splitting process, solidified film peeling process).

Then, by continuing to supply the stripping liquid, the solidified film 100, which has become film pieces 108, is washed away by the stripping liquid while still holding the etching residues 104. In other words, the film pieces 108 holding the etching residues 104 are pushed out of the substrate W and removed from the upper surface 151 of the substrate W (solidified film removal process, etching residue removal process). This allows the upper surface 151 of the substrate W to be cleaned well.

According to the first embodiment, the following effects are achieved.
According to the first embodiment, a semi-solid coating film 102 containing a first polymer and a second polymer is formed on the upper surface 151 of the substrate W. The first polymer in the coating film 102 etches the surface layer portion 150 of the substrate W. The second polymer in the coating film 102 is solidified by a heating treatment (solid formation treatment). This changes the coating film 102 to a solidified film 100. The first polymer is less likely to diffuse in the solidified film 100 than in the coating film 102. Therefore, the etching of the surface layer portion 150 of the substrate W by the first polymer is stopped by the coating film 102 changing into the solidified film 100.

In contrast to this method, in a technique for etching the surface layer 150 of the substrate W while continuously supplying an etching liquid such as hydrofluoric acid toward the upper surface 151 of the substrate W, the etching liquid is continuously discharged outside the substrate W.
On the other hand, the fluidity of the semi-solid coating film 102 is lower than the fluidity of the continuous flow etching liquid, so that it is possible to reduce the amount of the mixed liquid discharged outside the substrate W. As a result, it is possible to reduce the consumption of the first polymer, i.e., the consumption of the etching components.

When the surface layer 150 of the substrate W is etched using the first polymer in the coating film 102, etching residues 104 are likely to adhere to the upper surface 151 of the substrate W. In the method according to the first embodiment, in the solidified film removal process, the solidified film 100 is not dissolved in a stripping solution and removed from the upper surface 151 of the substrate W, but is peeled off and removed from the upper surface 151 of the substrate W. Therefore, the solidified film 100 is peeled off from the upper surface 151 of the substrate W while retaining the etching residues 104. As a result, the etching residues 104 can be removed from the upper surface 151 of the substrate W together with the solidified film 100.

According to the first embodiment, the etching process includes a liquid film etching process and a coating film etching process. Therefore, not only is the surface layer 150 of the substrate W etched by the first polymer in the coating film 102, but the surface layer 150 of the substrate W is also etched by the first polymer in the liquid film 101 of the mixed liquid that forms the base of the coating film 102. The first polymer in the liquid film 101 of the mixed liquid that contacts the upper surface 151 of the substrate W disappears by etching the surface layer 150 of the substrate W. The fluidity of the mixed liquid is higher than the fluidity of the semi-solid coating film 102.

Therefore, compared to etching with the coating film 102, when the first polymer near the upper surface 151 of the substrate W is lost by etching, the first polymer in the liquid film 101 of the mixed liquid is more likely to diffuse quickly than the first polymer in the coating film 102. Therefore, a decrease in the concentration of the first polymer near the upper surface 151 of the substrate W can be suppressed, and the surface layer 150 of the substrate W is quickly etched.

Furthermore, since etching is performed with a liquid film 101 of the mixed liquid formed on the upper surface of the substrate W, the amount of the first polymer discharged outside the substrate W, i.e., the consumption of the etching components, can be reduced compared to a method in which the surface portion 150 of the substrate W is etched while a continuous flow of an etching liquid such as hydrofluoric acid is supplied toward the upper surface 151 of the substrate W.
The liquid film etching step includes a mixed liquid film forming step of forming a liquid film of the mixed liquid from the first moving nozzle 9 facing the upper surface 151 of the substrate W toward the upper surface 151 of the substrate W. Therefore, the first polymer and the second polymer are supplied to the upper surface 151 of the substrate W in a pre-mixed state. Since it is not necessary to mix the first polymer and the second polymer on the upper surface 151 of the substrate W, the coating film 102 can be formed quickly. As a result, the time required for substrate processing can be shortened.

Furthermore, according to the first embodiment, the thermosetting resin as the second polymer in the coating film 102 is cured by heating. The coating film 102 changes into a solidified film 100 by the curing of the thermosetting resin. Since the solidified film 100 is formed by the curing of the thermosetting resin, the diffusion of the first polymer can be further suppressed. Therefore, the etching of the surface layer 150 of the substrate W by the first polymer can be more reliably stopped.

According to the first embodiment, the solidified film 100 contains a soluble component that is more soluble in the stripping liquid than the second polymer. The stripping liquid dissolves the soluble component solid 112 in the solidified film 100. The stripping liquid dissolves the soluble component solid 112 in the solidified film 100, forming a through hole 106 in the solidified film 100. Therefore, the stripping liquid can quickly reach the interface between the solidified film 100 and the substrate W through the through hole 106 formed in the solidified film 100. The stripping liquid enters the interface between the substrate W and the solidified film 100 and strips the solidified film 100 from the upper surface 151 of the substrate W. This allows the solidified film 100 to be quickly stripped from the upper surface 151 of the substrate W after etching by the first polymer is completed.

Because the second polymer is maintained in a solid state, the etching residue 104 can be held by the second polymer solid 111 even after the soluble component solid 112 has dissolved. Even when the solidified film 100 is removed from the upper surface of the substrate W by supplying a stripping liquid, the state in which the etching residue 104 is held by the solidified film 100 can be maintained. Therefore, compared to a case in which the etching residue 104 is not held by the solidified film 100, the energy (physical force) received from the flow of the stripping liquid can be increased. As a result, the etching residue 104 can be effectively removed from the upper surface of the substrate W by the stripping liquid.

Furthermore, according to the first embodiment, the etching residues 104 generated by etching the surface layer 150 of the substrate W are removed from the upper surface 151 of the substrate W together with the solidified film 100 in the solidified film removal step. Therefore, after removing the solidified film 100, there is no need to perform a separate process for removing the etching residues 104.
In the first embodiment, an organic acid polymer having a higher viscosity than a non-polymer organic acid such as acetic acid is used as the first polymer. Therefore, by using the organic acid polymer, the amount of liquid discharged from the substrate W when the organic acid polymer is used as an etching component to cover the upper surface of the substrate W can be reduced. Therefore, the amount of the etching component used can be reduced.

Second Embodiment
Fig. 7 is a schematic partial cross-sectional view showing a schematic configuration of a processing unit 2 provided in a substrate processing apparatus 1P according to a second embodiment. In Fig. 7, the same reference numerals as in Fig. 1 and the like are used for configurations equivalent to those shown in Fig. 1 to Fig. 6E described above, and descriptions thereof will be omitted (the same applies to Figs. 8 to 9B described later).

The main difference between the substrate processing apparatus 1P of the second embodiment and the substrate processing apparatus 1 of the first embodiment is that the processing unit 2 of the substrate processing apparatus 1P is configured so that the first polymer and the second polymer are ejected from separate nozzles.
In detail, the processing unit 2 includes a first moving nozzle 9P that supplies a first polymer liquid containing a first polymer toward the upper surface of the substrate W, and a fourth moving nozzle 12 that supplies a second polymer liquid containing a second polymer toward the upper surface of the substrate W.

The first movable nozzle 9P is an example of a first polymer liquid nozzle (first polymer liquid supply unit) that supplies (discharges) a first polymer liquid toward the upper surface of the substrate W held by the spin chuck 5.
Similar to the first moving nozzle 9 according to the first embodiment, the first moving nozzle 9P is moved in the horizontal and vertical directions by the first nozzle moving unit 35. The first moving nozzle 9P can move in the horizontal direction between a central position and a home position (retracted position).

The first moving nozzle 9P is connected to a first polymer liquid pipe 40P that guides the first polymer liquid to the first moving nozzle 9P. When a first polymer liquid valve 50P interposed in the first polymer liquid pipe 40P is opened, the first polymer liquid is ejected downward in a continuous flow from the ejection port of the first moving nozzle 9P. When the first polymer liquid valve 50P is opened while the first moving nozzle 9P is located at the central position, the first polymer liquid is supplied to the central region of the upper surface of the substrate W.

The first polymer liquid contains a solute and a solvent. The solvent contained in the first polymer liquid is, for example, an organic solvent. As the organic solvent, the organic solvents listed as the solvents contained in the mixed liquid according to the first embodiment can be used.
The first polymer liquid contains a first polymer as a solute. As the first polymer, any of the polymers listed as the first polymer contained in the mixed liquid according to the first embodiment can be used.

The fourth movable nozzle 12 is an example of a second polymer liquid nozzle (second polymer liquid supply unit) that supplies (discharges) the second polymer liquid toward the upper surface of the substrate W held by the spin chuck 5 .
The fourth movable nozzle 12 is moved in the horizontal and vertical directions by a fourth nozzle movement unit 38. The fourth movable nozzle 12 can move in the horizontal direction between a central position and a home position (retracted position).

When the fourth moving nozzle 12 is located at the central position, it faces a central region of the upper surface of the substrate W. When the fourth moving nozzle 12 is located at the home position, it does not face the upper surface of the substrate W and is located outside the processing cup 7 in a plan view. The fourth moving nozzle 12 can approach the upper surface of the substrate W or retreat upward from the upper surface of the substrate W by moving in the vertical direction.
The fourth nozzle moving unit 38 has a configuration similar to that of the first nozzle moving unit 35. That is, the fourth nozzle moving unit 38 may include an arm (not shown) connected to the fourth moving nozzle 12 and extending horizontally, a rotating shaft (not shown) connected to the arm and extending along the vertical direction, and a rotating shaft drive unit (not shown) that raises and lowers and rotates the rotating shaft.

The fourth moving nozzle 12 is connected to a second polymer liquid pipe 43 that guides the second polymer liquid to the fourth moving nozzle 12. When a second polymer liquid valve 53 interposed in the second polymer liquid pipe 43 is opened, the second polymer liquid is ejected downward in a continuous flow from the outlet of the fourth moving nozzle 12. When the second polymer liquid valve 53 is opened while the fourth moving nozzle 12 is located at the central position, the second polymer liquid is supplied to the central region of the upper surface of the substrate W.

The second polymer liquid contains a solute and a solvent. The solvent contained in the second polymer liquid is, for example, an organic solvent. As the organic solvent, the organic solvents listed as the solvents contained in the mixed liquid according to the first embodiment can be used.
The second polymer liquid contains a second polymer and a dissolved component as a solute. The second polymer can be a thermosetting resin as in the first embodiment. The thermosetting resin may contain at least one of an epoxy resin, a phenol resin, a melamine resin, an unsaturated polyester resin, and a polyurethane resin as in the first embodiment. Details of the dissolved component will be described later.

The substrate processing apparatus 1P according to the second embodiment can be used to perform substrate processing similar to that performed by the substrate processing apparatus 1 according to the first embodiment (see FIG. 4).
However, in substrate processing by the substrate processing apparatus 1P according to the second embodiment, the first polymer liquid and the second polymer liquid are mixed on the upper surface of the substrate W, thereby forming a mixed liquid on the upper surface of the substrate W. Fig. 8 is a schematic view for explaining a first example of the mixed liquid supplying step (step S2) in substrate processing by the substrate processing apparatus 1P according to the second embodiment.

Specifically, with the first moving nozzle 9P and the fourth moving nozzle 12 positioned at the processing position, the first polymer liquid valve 50P and the second polymer liquid valve 53 are opened. This causes the first polymer liquid to be ejected from the first moving nozzle 9P toward the top surface of the substrate W, and the second polymer liquid to be ejected from the fourth moving nozzle 12 toward the top surface of the substrate W. The supply of the first polymer liquid to the top surface of the substrate W and the supply of the second polymer liquid to the top surface of the substrate W are performed simultaneously.

The first polymer liquid and the second polymer liquid supplied to the upper surface of the substrate W are mixed on the upper surface of the substrate W to form a mixed liquid on the upper surface of the substrate W (mixed liquid formation process). As a result, the mixed liquid is supplied to the upper surface of the substrate W (mixed liquid supply process). The first polymer liquid and the second polymer liquid are mixed while spreading over the upper surface of the substrate W due to centrifugal force. As a result, a liquid film 101 of the mixed liquid is formed over the entire upper surface of the substrate W (mixed liquid film formation process). The ejection of the first polymer liquid and the ejection of the second polymer liquid may be started simultaneously. It is preferable that the liquid film 101 of the mixed liquid is in a puddle state.

The surface layer of the substrate W is etched by the first polymer (organic acid polymer) in the liquid film 101 of the mixed liquid (etching step, liquid film etching step).
The supply of the first polymer liquid from the first moving nozzle 9P and the supply of the second polymer liquid from the fourth moving nozzle 12 are continued for a predetermined time, for example, 2 to 4 seconds. In the mixed liquid supplying step, the substrate W is rotated at a predetermined mixed liquid rotation speed, for example, 10 rpm to 1500 rpm. The amount of the mixed liquid applied to the upper surface of the substrate W is about 2 cc.

The rotation speed of the substrate W in the mixed liquid supplying step (step S2) is preferably a speed at which the mixed liquid does not splash out of the substrate W, and it is preferable that a liquid film 101 of the mixed liquid forms a puddle on the substrate W.
Thereafter, the first polymer liquid valve 50P and the second polymer liquid valve 53 are closed, and the first moving nozzle 9P and the fourth moving nozzle 12 are moved toward the home position. Then, as described in the first embodiment, the evaporation (volatilization) of the solvent from the mixed liquid formed on the substrate W is promoted by the airflow generated by the action of the centrifugal force. As a result, as shown in FIG. 5B, a semi-solid coating film 102 is formed (coating film forming process). The surface layer of the substrate W is etched by the first polymer (organic acid polymer) in the coating film 102 (etching process, coating film etching process). In the second embodiment, the first moving nozzle 9P, the fourth moving nozzle 12, and the spin motor 23 constitute a coating film forming unit.

Etching of the surface layer of the substrate W starts simultaneously with the start of the deposition of the first polymer liquid on the upper surface of the substrate W, and ends with the formation of a solidified film 100 .
In a first example of substrate processing according to the second embodiment, the first polymer liquid and the second polymer liquid are mixed to form a mixed liquid on the substrate W. Therefore, even if the first polymer and the second polymer react with each other, the reaction between the first polymer and the second polymer can be suppressed before the first polymer and the second polymer are supplied to the upper surface of the substrate W.

Furthermore, the time required to form the coating film 102 can be reduced compared to a method in which the first polymer liquid and the second polymer liquid are sequentially supplied to the upper surface of the substrate W. As a result, the time required to process the substrate can be reduced.
In the substrate processing apparatus 1P according to the second embodiment, it is also possible to perform a substrate processing different from the first example of substrate processing shown in Fig. 8. For example, it is possible to perform a second example of substrate processing in which a first polymer liquid is supplied toward the upper surface of the substrate W in the mixed liquid supplying step (step S2), and after the supply of the first polymer liquid is completed, a second polymer liquid is supplied toward the upper surface of the substrate W. Figs. 9A and 9B are schematic views for explaining the second example of the mixed liquid supplying step (step S2) in the substrate processing by the substrate processing apparatus 1P.

The second example of substrate processing by the substrate processing apparatus 1P will now be described in detail. First, with the first moving nozzle 9P located at the processing position, the first polymer liquid valve 50P is opened. This causes the first polymer liquid to be supplied (discharged) from the first moving nozzle 9P toward the top surface of the substrate W (first polymer liquid supplying process, first polymer liquid discharging process). The first polymer liquid that has landed on the top surface of the substrate W spreads over the entire top surface of the substrate W due to centrifugal force, forming a liquid film 120 of the first polymer liquid over the entire top surface of the substrate W (first polymer liquid film forming process). It is preferable that the liquid film 120 is in a puddle state.

The supply of the first polymer liquid from the first moving nozzle 9P continues for a predetermined time, for example, 2 to 4 seconds. In the first polymer liquid supplying step, the substrate W is rotated at a predetermined first polymer liquid rotation speed, for example, 10 to 1500 rpm. The amount of the first polymer liquid applied to the upper surface of the substrate W is about 2 cc.
When a liquid film 120 of the first polymer liquid is formed on the upper surface of the substrate W, the first polymer liquid valve 50P is closed, and the first moving nozzle 9P is moved toward the home position. Meanwhile, the fourth moving nozzle 12 is moved toward the processing position. With the fourth moving nozzle 12 positioned at the processing position, the second polymer liquid valve 53 is opened. As a result, the second polymer liquid is supplied (discharged) from the fourth moving nozzle 12 toward the upper surface of the substrate W (second polymer liquid supplying step, second polymer liquid discharging step).

By supplying the second polymer liquid to the liquid film 120 of the first polymer liquid, the first polymer liquid and the second polymer liquid are mixed to form a mixed liquid (mixed liquid formation process). As a result, the mixed liquid is supplied to the upper surface of the substrate W (mixed liquid supply process). By mixing the second polymer liquid with the liquid film 120 of the first polymer liquid, a liquid film 101 of the mixed liquid is formed over the entire upper surface of the substrate W (mixed liquid film formation process). It is preferable that the liquid film 101 of the mixed liquid is in a puddle state.

The ejection of the second polymer liquid from the fourth moving nozzle 12 may be started before the ejection of the first polymer liquid from the first moving nozzle 9P is completed.
The surface layer of the substrate W is etched by the first polymer (organic acid polymer) in the liquid film 101 of the mixed liquid (etching step, liquid film etching step).
The supply of the second polymer liquid from the fourth moving nozzle 12 continues for a predetermined time, for example, 2 to 4 seconds. In the second polymer liquid supplying step, the substrate W is rotated at a predetermined second polymer liquid rotation speed, for example, 10 to 1500 rpm. The amount of the second polymer liquid applied to the upper surface of the substrate W is about 2 cc.

The rotation speed of the substrate W in the second polymer liquid supplying process is preferably a speed at which the second polymer liquid does not splash outside the substrate W, and it is preferable that the liquid film 101 of the second polymer liquid forms a puddle state on the substrate W.
Thereafter, the second polymer liquid valve 53 is closed, and the fourth moving nozzle 12 is moved toward the home position. Then, as described in the first embodiment, the evaporation (volatilization) of the solvent from the mixed liquid formed on the substrate W is promoted by the airflow generated by the action of centrifugal force. As a result, a semi-solid coating film 102 is formed as shown in Fig. 5B (coating film forming process). The surface layer of the substrate W is etched by the first polymer (organic acid polymer) in the coating film 102 (etching process, coating film etching process).

Etching of the surface layer of the substrate W starts simultaneously with the start of the deposition of the first polymer liquid on the upper surface of the substrate W, and ends with the formation of a solidified film 100 .
In a second example of the substrate processing according to the second embodiment, the first polymer liquid and the second polymer liquid are mixed to form a mixed liquid on the substrate W. Therefore, even if the first polymer and the second polymer react with each other, it is possible to suppress the reaction between the first polymer and the second polymer before the first polymer and the second polymer are supplied to the upper surface of the substrate W.

Furthermore, the first polymer liquid is supplied to the upper surface of the substrate W prior to the second polymer liquid. Therefore, the second polymer liquid is not mixed into the liquid film 120 on the upper surface of the substrate W. Therefore, the concentration of the first polymer in the liquid film 120 of the first polymer liquid is higher than the concentration of the first polymer in the liquid film 101 of the mixed liquid. Therefore, the surface layer of the substrate W can be etched in a short time by the first polymer in the liquid film 120 of the first polymer liquid.

Furthermore, after the first polymer is consumed to a certain extent as the etching progresses, the first polymer liquid and the second polymer liquid are mixed on the upper surface of the substrate W. Therefore, when the first polymer and the second polymer react with each other, the reaction between the first polymer and the second polymer can be further suppressed.

Third Embodiment
Fig. 10 is a schematic diagram showing a schematic configuration of a processing unit 2 provided in a substrate processing apparatus 1Q according to a third embodiment. In Fig. 10, the same reference numerals as in Fig. 1 and the like are used for configurations equivalent to those shown in Fig. 1 to Fig. 9B described above, and descriptions thereof will be omitted (the same applies to Fig. 11 described later).

The substrate processing apparatus 1Q according to the third embodiment mainly differs from the substrate processing apparatus 1 according to the first embodiment in that a light irradiation unit 8 is provided instead of the heater unit 6.
The light irradiation unit 8 includes a facing member 13 having a facing surface 13a that faces from above the top surface (upper surface) of the substrate W held by the spin chuck 5, and a plurality of lamps 80 attached to the facing surface 13a.

The facing member 13 is formed in a disk shape having a diameter substantially equal to or greater than that of the substrate W. The facing surface 13a is disposed above the spin chuck 5 and along a substantially horizontal plane.
A rotating shaft 130 is fixed to the opposing member 13 on the side opposite to the opposing surface 13a.
The facing member 13 isolates the atmosphere in the space between the facing surface 13a and the upper surface of the substrate W from the atmosphere outside the space. Therefore, the facing member 13 is also called a blocking plate.

The lamps 80 are arranged at equal intervals across the entire area of the opposing surface 13a. The processing unit 2 further includes a lamp energization unit 85 configured to energize the lamps 80 or stop energizing the lamps 80. The lamps 80 emit light when energized. Examples of the light emitted from each lamp 80 include infrared light, ultraviolet light, and visible light.

The processing unit 2 further includes a facing member lifting unit 131 that lifts and lowers the facing member 13, and a facing member rotating unit 132 that rotates the facing member 13 about the rotation axis A1.
The opposing member lifting unit 131 can position the opposing member 13 in the vertical direction at any position (height) between the lower position and the upper position. The lower position is a position where the opposing surface 13a is closest to the substrate W within the movable range of the opposing member 13. The upper position is a position where the opposing surface 13a is farthest from the substrate W within the movable range of the opposing member 13. When the opposing member 13 is located at the upper position, the transport robot CR can access the spin chuck 5 to load and unload the substrate W.

The opposing member lifting unit 131 includes, for example, a ball screw mechanism (not shown) coupled to a support member (not shown) that supports the rotating shaft 130, and an electric motor (not shown) that provides a driving force to the ball screw mechanism. The opposing member lifting unit 131 is also called an opposing member lifter (shield lifter). The opposing member rotation unit 132 includes, for example, a motor (not shown) that rotates the rotating shaft 130.

The opposing member lifting unit 131 lifts and lowers the multiple lamps 80 together with the opposing member 13. The opposing member lifting unit 131 is an example of a lamp lifting unit (lamp lifter). The opposing member rotation unit 132 rotates the multiple lamps 80 together with the opposing member 13. The opposing member rotation unit 132 is an example of a lamp rotation unit (lamp rotation motor).

Unlike the third embodiment, the opposing member 13 may be attached to, for example, the upper wall of the chamber 4 and fixed thereto.
The solvent contained in the mixed liquid is, for example, an organic solvent. As the organic solvent, the organic solvents listed as the solvents contained in the mixed liquid according to the first embodiment can be used. As the first polymer contained in the mixed liquid, the polymers listed as the first polymers contained in the mixed liquid according to the first embodiment can be used.

The second polymer contained in the mixed liquid according to the third embodiment is a photocurable resin that is cured by irradiation with light, unlike the second polymer contained in the mixed liquid according to the first embodiment. Examples of photocurable resins include epoxy resins and acrylic resins.
The lamp current supply unit 85, the opposing member lifting unit 131 and the opposing member rotating unit 132 are controlled by the controller 3 (see FIG. 3).

The substrate processing apparatus 1Q according to the third embodiment can perform the same substrate processing as that according to the first embodiment (see FIG. 4), except that in the solidified film forming step (step S4), the coating film 102 is irradiated with light.
In detail, after the coating film forming process (step S3), the facing member lifting unit 131 places the facing member 13 at a processing position between the upper position and the lower position. When the facing member 13 is located at the processing position, the lamp 80 is energized, and light is irradiated onto the coating film 102 (see FIG. 5B) on the substrate W. As a result, as shown in FIG. 11, a solidified film 100 is formed, and etching of the surface layer of the substrate W is stopped (etching stop process). Since the solidified film 100 is formed by light irradiation, light irradiation is an example of a solid formation process. The light irradiation unit 8 is an example of a solid formation unit.

As shown in Figure 12, the state near the surface of the substrate W during substrate processing is almost the same as in the first embodiment, except that the coating film 102 is converted into a solidified film 100 by irradiating the coating film 102 with light.
According to the third embodiment, the same effects as those of the first embodiment are achieved.
Furthermore, the solid formation process includes a light irradiation process on the coating film 102, and the second polymer is a photocurable resin. Therefore, the photocurable resin as the second polymer in the coating film is hardened by the irradiation of light. The coating film 102 is changed into a solidified film 100 by the hardening of the photocurable resin. Since the solidified film 100 is formed by the hardening of the photocurable resin, the diffusion of the etching components can be further suppressed. Therefore, the etching of the surface layer 150 of the substrate W by the etching components can be more reliably stopped.

The substrate processing apparatus 1Q of the third embodiment may be configured so that the first polymer liquid and the second polymer liquid are mixed on the substrate W. Specifically, instead of the first moving nozzle 9, the first moving nozzle 9P and the fourth moving nozzle 12 of the second embodiment may be provided as shown in FIG. 13. With this configuration, it is possible to perform substrate processing similar to that of the second embodiment (see FIGS. 8 to 9B).

Next, modified examples of the light irradiation unit 8 will be described with reference to Fig. 14 and Fig. 15. Fig. 14 is a schematic diagram for describing a first modified example of the light irradiation unit 8. Fig. 15 is a schematic diagram for describing a second modified example of the light irradiation unit 8.
For example, as in a first modified example shown in FIG. 14 , the light irradiation unit 8 may be configured to be moved between the irradiation position and a home position (retracted position) by a lamp moving unit 86 provided in the chamber 4.

The irradiation position is a position where the light irradiation unit 8 faces the upper surface of the substrate W. The irradiation position is a position where the light irradiation unit 8 can irradiate the upper surface of the substrate W with light. The retracted position is a position where the light irradiation unit 8 does not irradiate the upper surface of the substrate W with light. When the light irradiation unit 8 is located at the irradiation position, the light irradiation unit 8 faces the upper surface of the substrate W. When the light irradiation unit 8 is located at the home position, the light irradiation unit 8 does not face the upper surface of the substrate W and is located outside the processing cup 7 in a planar view.

14, the light irradiation unit 8 includes a lamp 80 and a lamp holder 81 that houses the lamp 80. The lamp moving unit 86 includes an arm 87 that supports the lamp holder 81, a rotation shaft 89 that is connected to the arm 87 and extends vertically, and an arm moving unit 88 that moves the arm 87 via the rotation shaft 89. The arm moving unit 88 includes, for example, a motor that rotates the rotation shaft 89 about its central axis (rotation axis A2) in order to move the arm 87 horizontally, and a ball screw mechanism that raises and lowers the arm 87 together with the rotation shaft 89.
As a second modified example shown in FIG. 15, the lamp 80 may be rod-shaped and disposed within an arm 87 that extends linearly.

Fourth Embodiment
16 is a schematic diagram for explaining the configuration of a substrate processing apparatus 1R according to a fourth embodiment. The substrate processing apparatus 1R according to the fourth embodiment is mainly different from the substrate processing apparatus 1Q according to the third embodiment in that the substrate processing apparatus 1R is configured such that the formation of the solidified film 100 and the peeling of the solidified film 100 are performed in separate chambers 4A and 4B.

The substrate processing apparatus 1R includes a solidified film forming processing unit 2A that forms the solidified film 100 and a solidified film removing processing unit 2B that removes the solidified film 100.
The solidified film forming processing unit 2A includes a spin chuck 5A that rotates the substrate W while holding the substrate W horizontally, a first moving nozzle 9 that supplies a mixed liquid to the upper surface of the substrate W, and a chamber 4A that accommodates the spin chuck 5A and the first moving nozzle 9.

The chamber 4A is formed with an entrance 4Aa through which the transport robot CR loads and unloads the substrate W. The chamber 4A is provided with a shutter unit 4Ab for opening and closing the entrance.
The solidified film forming processing unit 2A further includes a light irradiation unit 8 that irradiates light onto the substrate W passing through the entrance 4Aa of the chamber 4A. The light irradiation unit 8 includes a lamp that emits, for example, infrared light, ultraviolet light, visible light, etc. The light irradiation unit 8 is attached to the side wall of the chamber 4A.

The solidified film removal processing unit 2B includes a spin chuck 5B that rotates the substrate W while holding it horizontally, a second moving nozzle 10 that supplies a stripping liquid to the upper surface of the substrate W, a third moving nozzle 11 that supplies a rinsing liquid to the upper surface of the substrate W, and a chamber 4B that accommodates the spin chuck 5B, the second moving nozzle 10 and the third moving nozzle 11.
The chamber 4B is formed with an entrance 4Ba through which the transport robot CR loads and unloads the substrate W. The chamber 4B is provided with a shutter unit 4Bb for opening and closing the entrance.

In substrate processing by the substrate processing apparatus 1R according to the fourth embodiment, the substrate W is loaded into the chamber 4A (first chamber) of the solidified film forming processing unit 2A by the transport robot CR, and then the mixed liquid supply process (step S2) and the coated film forming process (step S3) shown in FIG. 4 are performed in the chamber 4A. That is, from the start of the mixed liquid supply process (step S2) to the end of the coated film forming process (step S3), the substrate W is held by the spin chuck 5A in the chamber 4A (first substrate holding process).

Then, as shown in FIG. 16, the substrate W with the coating film 102 formed on its upper surface is transported out of the chamber 4A of the solidified film formation processing unit 2A by the transport robot CR (transport step). When the substrate W passes through the entrance 4Aa of the chamber 4A, the second polymer in the coating film 102 is hardened by the light irradiation unit 8 to form a solidified film 100. That is, the solidified film formation step (step S4) is performed during the transport step. The substrate W with the solidified film 100 formed on its upper surface is transported into the chamber 4B of the solidified film removal processing unit 2B (transport step). The transport robot CR is an example of a transport unit.

Then, in chamber 4B, the solidified film removal process (step S5), the rinsing process (step S6), and the spin drying process (step S7) shown in FIG. 4 are performed. That is, from the start of the solidified film removal process (step S5) to the end of the spin drying process (step S7), the substrate W is held by the spin chuck 5B in chamber 4B (second substrate holding process).

According to the fourth embodiment, the same effects as those of the third embodiment can be obtained. Furthermore, according to the fourth embodiment, in a configuration in which the formation of the solidified film 100 and the removal of the solidified film 100 are performed in separate chambers 4A and 4B, the solidified film 100 can be formed while the substrate W is being transported. Therefore, the time required for substrate processing can be shortened.
Although not shown in FIG. 16, the solidified film forming processing unit 2A and the solidified film removal processing unit 2B may be provided with a processing cup 7 (see FIG. 2).

<Details of soluble components>
The soluble components used in the above-described embodiments are described below.
Hereinafter, descriptions such as "C _x-y ,""C _{x -C y} ," and "C _x " refer to the number of carbons in a molecule or substituent. For example, C _1-6 alkyl refers to an alkyl chain having from 1 to 6 carbons (methyl, ethyl, propyl, butyl, pentyl, hexyl, etc.).
When a polymer has multiple types of repeating units, these repeating units are copolymerized. Unless otherwise specified, these copolymerizations may be alternating copolymerization, random copolymerization, block copolymerization, graft copolymerization, or a mixture of these. When a polymer or resin is shown by a structural formula, n, m, etc. shown in parentheses indicate the number of repeats.

The soluble component is a crack-promoting component. The crack-promoting component contains a hydrocarbon and further contains a hydroxyl group (-OH) and/or a carbonyl group (-C(=O)-). When the crack-promoting component is a polymer, one of the constituent units contains a hydrocarbon in each unit and further has a hydroxyl group and/or a carbonyl group. Examples of carbonyl groups include carboxylic acids (-COOH), aldehydes, ketones, esters, amides, and enones, with carboxylic acids being preferred.

Without intending to limit the scope of the rights and not being bound by theory, it is believed that when the coating film is dried to form a solidified film on the substrate, and the stripping solution strips the solidified film, the soluble components produce areas that trigger the solidified film to peel off. For this reason, it is preferable that the soluble components have a higher solubility in the stripping solution than the low-solubility components. Examples of forms in which the crack-promoting component contains a ketone as a carbonyl group include cyclic hydrocarbons. Specific examples include 1,2-cyclohexanedione and 1,3-cyclohexanedione.

In a more specific embodiment, the soluble component is represented by at least one of the following (A), (B) and (C).
(A) is a compound containing 1 to 6 (preferably 1 to 4) constituent units of the following chemical formula 3, and each constituent unit is linked by a linking group (linker L ₁ ). Here, the linker L ₁ may be a single bond or a C _1-6 alkylene. The C _1-6 alkylene links the constituent units as a linker, and is not limited to a divalent group. It is preferably divalent to tetravalent. The C _1-6 alkylene may be either linear or branched.

Cy ₁ is a _C5-30 hydrocarbon ring, preferably phenyl, cyclohexane or naphthyl, more preferably phenyl. In a preferred embodiment, the linker L ₁ connects a plurality of Cy _1's .
Each R ₁ is independently a C _1-5 alkyl, preferably methyl, ethyl, propyl, or butyl. The C _1-5 alkyl may be linear or branched.

n _b1 is 1, 2 or 3, preferably 1 or 2, and more preferably 1. n _b1′ is 0, 1, 2, 3 or 4, and preferably 0, 1 or 2.
The following Chemical Formula 4 is a chemical formula in which the structural unit described in Chemical Formula 3 is expressed using a linker L _9. The linker L ₉ is preferably a single bond, methylene, ethylene, or propylene.

Without intending to limit the scope of the right, suitable examples of (A) include 2,2-bis(4-hydroxyphenyl)propane, 2,2'-methylenebis(4-methylphenol), 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-methylphenol, 1,3-cyclohexanediol, 4,4'-dihydroxybiphenyl, 2,6-naphthalenediol, 2,5-di-tert-butylhydroquinone, and 1,1,2,2-tetrakis(4-hydroxyphenyl)ethane. These may be obtained by polymerization or condensation.

As an example, 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-methylphenol shown in the following chemical formula 5 will be described. In (A), this compound has three structural units of chemical formula 3, which are linked by a linker L ₁ (methylene). n _b1 =n _b1' =1, and R ₁ is methyl.

(B) is represented by the following chemical formula 6.

R ₂₁ , R ₂₂ , R ₂₃ , and R ₂₄ are each independently hydrogen or C _1-5 alkyl, preferably hydrogen, methyl, ethyl, t-butyl, or isopropyl, more preferably hydrogen, methyl, or ethyl, and even more preferably methyl or ethyl.
The linkers L ₂₁ and L ₂₂ are each independently a C _1-20 alkylene, a C _1-20 cycloalkylene, a C _2-4 alkenylene, a C _2-4 alkynylene, or a C _6-20 arylene. These groups may be substituted with a C _1-5 alkyl or hydroxy. Here, alkenylene means a divalent hydrocarbon having one or more double bonds, and alkynylene means a divalent hydrocarbon group having one or more triple bonds. The linkers L ₂₁ and L ₂₂ are preferably a C _2-4 alkylene, acetylene (C ₂ alkynylene), or phenylene, more preferably a C _2-4 alkylene or acetylene, and even more preferably acetylene.

n _b2 is 0, 1 or 2, preferably 0 or 1, and more preferably 0.
Although there is no intention to limit the scope of the invention, suitable examples of (B) include 3,6-dimethyl-4-octyne-3,6-diol and 2,5-dimethyl-3-hexyne-2,5-diol. In another embodiment, suitable examples of (B) include 3-hexyne-2,5-diol, 1,4-butynediol, 2,4-hexadiyne-1,6-diol, 1,4-butanediol, cis-1,4-dihydroxy-2-butene, and 1,4-benzenedimethanol.

(C) is a polymer containing a structural unit represented by the following chemical formula 7 and having a weight average molecular weight (Mw) of 500 to 10,000. Mw is preferably 600 to 5,000, and more preferably 700 to 3,000.

Here, R ₂₅ is —H, —CH ₃ , or —COOH, and preferably —H or —COOH. It is also acceptable for one (C) polymer to comprise two or more types of constitutional units each represented by Chemical Formula 7.
Although not intending to limit the scope of the invention, preferred examples of the polymer (C) include polymers of acrylic acid, maleic acid, or a combination thereof. More preferred examples include polyacrylic acid and maleic acid-acrylic acid copolymers.

In the case of copolymerization, random copolymerization or block copolymerization is preferred, and random copolymerization is more preferred.
As an example, a maleic acid acrylic acid copolymer shown in the following chemical formula 8 will be described. This copolymer is included in (C) and has two types of structural units represented by chemical formula 7, where R ₂₅ in one structural unit is -H and R ₂₅ in the other structural unit is -COOH.

Needless to say, the soluble component may contain one or a combination of two or more of the above preferred examples. For example, the soluble component may contain both 2,2-bis(4-hydroxyphenyl)propane and 3,6-dimethyl-4-octyne-3,6-diol.
The soluble component may have a molecular weight of 80 to 10,000. The soluble component preferably has a molecular weight of 90 to 5000, more preferably 100 to 3000. When the soluble component is a resin, polymer or polymer, the molecular weight is expressed as the weight average molecular weight (Mw).
The soluble components can be obtained either synthetically or commercially from suppliers such as Sigma-Aldrich, Tokyo Chemical Industry Co., Ltd., and Nippon Shokubai.

<Other embodiments>
The present invention is not limited to the above-described embodiment, and can be embodied in other forms.
The spin chuck 5 is not limited to a clamping type chuck that brings multiple chuck pins 20 into contact with the peripheral edge surface of the substrate W, but may also be a vacuum type chuck that holds the substrate W horizontally by adsorbing the lower surface of the substrate W to the upper surface of the spin base 21.
Furthermore, while each liquid (mixed liquid, first polymer liquid, second polymer liquid, stripping liquid, and rinsing liquid) in the above-described embodiments is configured to be ejected from a movable nozzle, each substrate processing apparatus 1, 1P, 1Q, and 1R may be configured to eject liquid from a fixed nozzle whose position relative to the substrate W is fixed.

In the above-described embodiment, the coating film 102 is heated by the heater unit 6. However, the coating film 102 may be heated by supplying hot water to the lower surface of the substrate W, for example.
In the above-described embodiment, the spin dry process is performed after the rinsing process. However, after the upper surface of the substrate W is cleaned with a rinsing liquid such as pure water in the rinsing process, the rinsing liquid may be replaced with an organic solvent such as IPA, and then the spin dry process may be performed.

In the above-described embodiment, the coating film 102 is formed from the liquid film 101 of the mixed liquid. However, unlike the above-described embodiment, the coating film 102 may be formed on the upper surface of the substrate W by applying a high-viscosity coating agent containing a first polymer and a second polymer to the upper surface of the substrate W. The coating agent may contain a solvent, but if the first polymer and the second polymer have a fluidity sufficient to enable application, the coating agent may not contain a solvent.

In this specification, when numerical ranges are indicated using "to" or "-", they include both endpoints and have the same units, unless otherwise specifically stated.
In addition, various modifications can be made within the scope of the claims.

1: Substrate processing apparatus 1P: Substrate processing apparatus 1Q: Substrate processing apparatus 1R: Substrate processing apparatus 3: Controller 6: Heater unit (solid formation unit)
8: Light irradiation unit (solid formation unit)
9: First moving nozzle (coating film forming unit)
9P: First moving nozzle (coating film forming unit)
10: Second moving nozzle (stripping liquid supply unit)
12: Fourth moving nozzle (coating film forming unit)
23: Spin motor (coating film forming unit)
100: solidified film 102: coating film 104: etching residue 150: surface layer 151: upper surface (surface)
W: Substrate

Claims (12)

an etching step of forming a semi-solid coating film containing a first polymer having an etching function and a second polymer having a solid-forming function on a surface of a substrate, and etching a surface layer of the substrate with the first polymer on the substrate;
and an etching stopping step of stopping etching of the surface portion of the substrate by hardening the second polymer in the coating film through a solid forming process to change the coating film into a solidified film. The substrate processing method according to claim 1, wherein the etching step includes a liquid film etching step of forming a liquid film of a mixed liquid containing the first polymer and the second polymer, and etching a surface portion of the substrate with the first polymer in the liquid film of the mixed liquid, and a coating film etching step of forming the coating film from the liquid film of the mixed liquid, and etching a surface portion of the substrate with the first polymer in the coating film. The substrate processing method according to claim 2, wherein the liquid film etching process includes a mixed liquid film forming process in which the mixed liquid is discharged toward the surface of the substrate from a nozzle facing the surface of the substrate to form a liquid film of the mixed liquid. The substrate processing method according to claim 2, wherein the liquid film etching step includes a mixed liquid film forming step of supplying a first polymer liquid containing the first polymer and a second polymer liquid containing the second polymer to the upper surface of the substrate to form a liquid film of the mixed liquid of the first polymer liquid and the second polymer liquid on the upper surface of the substrate. The substrate processing method according to claim 4, wherein the mixed liquid film forming process includes a process of simultaneously supplying the first polymer liquid to the surface of the substrate and supplying the second polymer liquid to the surface of the substrate. The substrate processing method according to claim 4, wherein the mixed liquid film forming process includes a first polymer liquid supplying process of supplying the first polymer liquid toward the surface of the substrate, and a second polymer liquid supplying process of supplying the second polymer liquid toward the surface of the substrate after the first polymer liquid supplying process to form a liquid film of the mixed liquid on the surface of the substrate. the solid forming treatment includes a heat treatment of the coating film,
The substrate processing method according to any one of claims 1 to 6, wherein the second polymer is a thermosetting resin. the solid forming treatment includes a light irradiation treatment of the coating film,
The substrate processing method according to any one of claims 1 to 6, wherein the second polymer is a photocurable resin. The substrate processing method according to any one of claims 1 to 8, further comprising a solidified film removal step of supplying a stripping liquid to the surface of the solidified film to strip the solidified film from the surface of the substrate, thereby removing the solidified film from the surface of the substrate. In the etching stopping step, the solidified film is formed, which contains a soluble component that is more soluble in the stripping solution than the second polymer,
The substrate processing method according to claim 9 , wherein the soluble component in the solidified film is dissolved by the stripping solution supplied in the solidified film removing step. In the etching step, a surface layer portion of the substrate is etched to form an etching residue,
the etching residue is held by the solidified film formed in the etching stopping step,
11. The substrate processing method according to claim 9, wherein the solidified film removing step comprises the step of removing the etching residue together with the solidified film while the etching residue is held by the solidified film. a coating film forming unit for forming a coating film containing a first polymer having an etching function and a second polymer having a solid forming function on a surface of a substrate;
a solid forming unit that performs a solid forming process to form a solidified film by solidifying or curing the second polymer in the coating film on the surface of the substrate;
a stripping solution supplying unit that supplies a stripping solution toward the surface of the substrate to strip the solidified film from the surface of the substrate;
a controller for controlling the coating film forming unit, the solid forming unit, and the stripping liquid supply unit;
a substrate processing apparatus, the substrate processing apparatus being programmed such that the controller is programmed to execute an etching process in which the coating film is formed on the surface of the substrate by the coating film forming unit, and a surface portion of the substrate is etched by the first polymer in the coating film; an etching stopping process in which the etching of the surface portion of the substrate is stopped by hardening the second polymer in the coating film by the solid formation process by the solid formation unit, thereby changing the coating film into a solidified film; and a solidified film removal process in which the solidified film is peeled off from the surface of the substrate by supplying a stripping liquid to the surface of the solidified film, thereby removing the solidified film from the surface of the substrate.

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