JP2021141086A - Substrate processing method and substrate processing apparatus - Google Patents

Abstract

To provide a substrate processing method and a substrate processing apparatus that are configured to form a vapor phase layer between a liquid film of processing liquid and a top surface of a substrate when removing the processing liquid from the top surface of the substrate and that can excellently remove the processing liquid from the top surface of the substrate.SOLUTION: A substrate W is heated entirely to a temperature lower than the boiling point of low surface tension liquid so as to insulate the heat of a liquid film L of the low surface tension liquid (liquid film heat insulation process). While the liquid film heat insulation process is executed, an irradiated region RR is heated through irradiation with light from a lamp unit 12 to form a vapor phase layer VL at the center part of the liquid film L (vapor phase layer formation process). The low surface tension liquid held with the vapor phase layer VL is removed to form an opening 100 at the center part of the liquid film L (opening formation process). While the liquid film heat insulation process and a substrate rotation process are executed, the irradiated region RR is moved toward a peripheral edge part of the substrate W so as to expand the opening 100 while maintaining the state in which the vapor phase layer VL is formed at an inner peripheral edge of a liquid film R.SELECTED DRAWING: Figure 8E

Description

The present invention relates to a substrate processing method and a substrate processing apparatus for processing a substrate. The substrates to be processed include, for example, semiconductor wafers, substrates for liquid crystal displays, substrates for FPDs (Flat Panel Display) such as organic EL (Electroluminescence) display devices, substrates for optical disks, substrates for magnetic disks, and substrates for opto-magnetic disks. Includes substrates such as substrates, photomask substrates, ceramic substrates, and solar cell substrates.

In substrate processing by a single-wafer type substrate processing apparatus that processes substrates one by one, for example, a chemical solution is supplied to a substrate held substantially horizontally by a spin chuck. After that, the rinse solution is supplied to the substrate, whereby the chemical solution on the substrate is replaced with the rinse solution. After that, a spin-drying step is performed to remove the rinse liquid on the substrate.
When a pattern is formed on the surface of the substrate, the rinse liquid that has entered the inside of the pattern may not be removed in the spin-drying process. This may cause poor drying of the substrate. Since the liquid level (interface between air and liquid) of the rinse liquid that has entered the inside of the pattern is formed inside the pattern, the surface tension of the liquid acts at the contact position between the liquid level and the pattern. When this surface tension is large, the pattern is likely to collapse. Water, which is a typical rinsing liquid, has a large surface tension, so that the pattern collapse in the spin-drying process cannot be ignored.

Therefore, it has been proposed to supply isopropyl alcohol (IPA), which is an organic solvent having a lower surface tension than water. By treating the upper surface of the substrate with IPA, the water that has entered the inside of the pattern is replaced with IPA. The IPA is then removed to dry the top surface of the substrate.
However, in recent years, fine patterns (columnar patterns, line-shaped patterns, etc.) having a high aspect ratio have been formed on the surface of the substrate for high integration. Fine and high aspect ratio fine patterns are easy to collapse. Therefore, it is necessary to shorten the time during which surface tension acts on the fine pattern after the IPA liquid film is formed on the upper surface of the substrate.

Therefore, Patent Document 1 below proposes a substrate processing method for forming a gas phase layer of IPA. In this substrate processing method, the substrate is heated by the heater, so that the vapor phase layer of IPA is formed between the liquid film of IPA and the upper surface of the substrate. As a result, since the inside of the fine pattern is filled with the gas phase IPA, the time for the surface tension to act on the fine pattern can be shortened as compared with the method of gradually evaporating the IPA inside the fine pattern from above. ..

Japanese Unexamined Patent Publication No. 2014-112652

In the substrate processing method described in Patent Document 1, the IPA liquid film is removed from the substrate while maintaining a state in which the IPA liquid film floats from the upper surface of the substrate and does not come into contact with the upper surface of the substrate. In Patent Document 1, as a method of removing the liquid film of IPA from the substrate in a state where the vapor phase layer is formed, for example, a method of tilting the substrate to slide off the liquid film of IPA (FIGS. 11A to 11A of Patent Document 1). (See FIG. 11C), a method of removing the IPA liquid film by sucking the IPA liquid film with a suction nozzle (see FIGS. 12A to 12C of Patent Document 1), and the like are disclosed.

In these methods, if the liquid film is not removed after the entire liquid film of IPA has floated from the upper surface of the substrate, IPA may remain on the upper surface of the substrate. Therefore, it is necessary to sufficiently heat the substrate with a heater. On the contrary, if the substrate is heated too much, the IPA may evaporate locally and the liquid film may split while the substrate is heated by the heater in order to float the entire liquid film of the IPA.

Therefore, one object of the present invention is to form a vapor phase layer between the liquid film of the treatment liquid and the upper surface of the substrate when the treatment liquid is removed from the upper surface of the substrate, and the treatment liquid is removed from the upper surface of the substrate. It is an object of the present invention to provide a substrate processing method and a substrate processing apparatus which can be satisfactorily eliminated.

One embodiment of the present invention is based on a liquid film forming step of supplying a treatment liquid to the upper surface of a horizontally held substrate to form a liquid film of the treatment liquid on the upper surface of the substrate, and a boiling point of the treatment liquid. While executing the liquid film heat retaining step of keeping the liquid film warm by heating the entire substrate to a low temperature and the liquid film heat retaining step, the irradiation unit facing the upper surface of the substrate to the upper surface of the substrate. By irradiating the irradiation region set in the central portion of the substrate with light to heat the central portion of the upper surface of the substrate, the treatment liquid in contact with the central portion of the upper surface of the substrate is evaporated and comes into contact with the upper surface of the substrate. By forming a gas phase layer forming step of forming a gas phase layer holding the treatment liquid in the central portion of the liquid film and removing the treatment liquid held by the gas phase layer, the vapor phase layer is formed in the central portion of the liquid film. The opening forming step of forming the opening, the substrate rotating step of rotating the substrate around the rotation axis extending in the vertical direction through the central portion of the upper surface of the substrate, the liquid film heat retaining step, and the substrate rotating step are executed. This includes an opening expansion step of expanding the opening while maintaining a state in which the vapor phase layer is formed on the inner peripheral edge of the liquid film by moving the irradiation region toward the peripheral edge of the substrate. A substrate processing method is provided.

According to this method, the irradiation region set in the central portion of the upper surface of the substrate is irradiated with light to heat the central portion of the upper surface of the substrate. As a result, the treatment liquid in contact with the central portion of the upper surface of the substrate evaporates, and the vapor phase layer is formed in the central portion of the upper surface of the substrate. By forming the gas phase layer, the liquid film floats from the central portion of the upper surface of the substrate. An opening is formed in the central portion of the liquid film by eliminating the treatment liquid held by the vapor phase layer formed in the central portion of the upper surface of the substrate. After the opening is formed, the heating region is moved toward the peripheral edge of the substrate while rotating the substrate, so that the opening is expanded while maintaining the state in which the vapor phase layer is formed on the inner peripheral edge of the liquid film. .. In other words, when the liquid film is removed from the upper surface of the substrate, the annular region (gas phase layer forming region) in which the gas phase layer is formed moves toward the peripheral edge of the upper surface of the substrate as the opening expands. ..

Therefore, as compared with the method in which the liquid film held in the gas phase layer is eliminated after the gas phase layer is formed in the entire upper surface of the substrate, the gas phase layer is formed and then held in the gas phase layer. The time until the treatment liquid is removed can be shortened at any place on the upper surface of the substrate. This makes it possible to prevent the entire substrate from being overheated during the formation and expansion of the openings. Therefore, it is possible to prevent the treatment liquid from locally evaporating and splitting the liquid film.

Further, the formation and expansion of the opening are performed while keeping the liquid film of the treatment liquid warm. Therefore, the gas phase layer can be quickly formed in the irradiation region. Further, it is possible to suppress a temperature drop of the substrate in a non-irradiated region (particularly, a region opposite to the irradiation region with respect to the rotation center position of the upper surface of the substrate W) on the upper surface of the substrate. Therefore, it is possible to prevent the formed gas phase layer from moving out of the irradiation region and disappearing due to the rotation of the substrate.

As described above, the processing liquid can be satisfactorily removed from the upper surface of the substrate. As a result, it is possible to suppress pattern collapse due to surface tension of the treatment liquid and particle generation due to poor drying.
In one embodiment of the present invention, the opening expansion step comprises a liquid film forming region in which the liquid film is formed on the upper surface of the substrate and an opening forming region in which the opening is formed on the upper surface of the substrate. The step of moving the irradiation region following the expansion of the opening is included so that the irradiation region is arranged so as to straddle the irradiation region.

When the substrate is heated with the openings formed in the liquid film, the temperature of the substrate rises rapidly because the treatment liquid does not exist in the region where the openings are formed on the upper surface of the substrate. As a result, a temperature difference occurs between the inside of the inner peripheral edge of the liquid film (opening forming region) and the outer side of the inner peripheral edge of the liquid film (liquid film forming region). Specifically, the temperature of the substrate is high in the opening forming region, and the temperature of the substrate is low in the liquid film forming region. Due to this temperature difference, heat convection is generated in which the treatment liquid moves to the low temperature side, so that the opening is expanded, whereby the treatment liquid is discharged to the outside of the substrate.

Therefore, if the irradiation region is moved according to the expansion of the opening so that the irradiation region is arranged so as to straddle the liquid film forming region and the opening forming region, the liquid film forming region and the opening forming region may be used. A sufficient temperature difference can be generated and heat convection can be generated in the liquid film.
On the other hand, the inner peripheral edge of the liquid film can be heated with a sufficient amount of heat. Therefore, it is possible to suppress the occurrence of a situation in which the gas phase layer is not formed on the inner peripheral edge of the liquid film due to insufficient heat, or a situation in which the once formed gas phase layer disappears and the treatment liquid comes into contact with the upper surface of the substrate. That is, a gas phase layer can be stably formed on the inner peripheral edge of the liquid film.

In one embodiment of the present invention, the liquid film heat retaining step is a heater heating step of heating the liquid film by heating the substrate by a heater unit facing the lower surface of the substrate at a position separated from the lower surface of the substrate. including.
According to this method, the substrate is heated by a heater unit arranged at a position separated from the lower surface of the substrate. Therefore, regardless of the configuration of the heater unit, that is, even if the heater unit cannot rotate with the substrate, the substrate can be easily rotated when the opening is expanded. Further, as compared with the configuration in which the heater unit is brought into contact with the substrate, the entire substrate can be appropriately heated. Further, it is possible to prevent the dirt adhering to the heater unit from being transferred to the substrate.

In one embodiment of the present invention, the liquid film heat retaining step includes a fluid heating step of heating the liquid film by supplying a heating fluid to the central portion of the lower surface of the substrate to heat the substrate.
When the opening is expanded, the heating fluid supplied to the central portion of the lower surface of the substrate spreads toward the peripheral edge of the lower surface of the substrate by the action of centrifugal force caused by the rotation of the substrate. Therefore, the entire substrate can be heated only by supplying the heating fluid to the central portion of the lower surface of the substrate.

In one embodiment of the present invention, the opening forming step creates the opening in the central portion of the liquid film by maintaining the irradiation region in the central portion of the upper surface of the substrate after the vapor phase layer is formed. Including the step of forming.
According to this method, the irradiation region is maintained in the central portion of the upper surface of the substrate even after the vapor phase layer is formed. Therefore, even after the vapor phase layer is formed, the central portion of the upper surface of the substrate is heated, so that the evaporation of the treatment liquid held in the vapor phase layer is promoted. Further, on the upper surface of the substrate, a large temperature difference occurs between the irradiation region and the region outside the irradiation region. Due to this temperature difference, heat convection flowing from the central portion to the peripheral portion is formed on the upper surface of the substrate. Due to the evaporation of the treatment liquid and the generation of heat convection, an opening can be rapidly formed in the central portion of the liquid film of the treatment liquid.

In one embodiment of the present invention, the substrate treatment method comprises an opening formation promoting step of promoting the formation of the opening by blowing a gas toward the central portion of the liquid film on which the gas phase layer is formed. Including further.
When the gas phase layer is formed, the frictional resistance acting on the liquid film on the substrate is so small that it can be regarded as zero. If the method is to blow the gas toward the central portion of the liquid film on which the gas phase layer is formed, the treatment liquid in the central portion of the substrate can be quickly repelled. Thereby, the formation of the opening can be promoted.

In one embodiment of the present invention, in the substrate processing method, when the inner peripheral edge of the liquid film reaches the peripheral edge of the upper surface of the substrate, a gas is formed on the upper surface of the substrate inward of the inner peripheral edge of the liquid film. Further includes an expansion promoting step of promoting the expansion of the opening by spraying.
In the movement of the treatment liquid using heat convection, the opening can be expanded to some extent, but when the outer peripheral edge of the opening reaches the peripheral edge of the upper surface of the substrate, the movement of the treatment liquid may stop. More specifically, when the outer peripheral edge of the opening reaches the peripheral edge of the upper surface of the substrate, the total amount of the processing liquid on the substrate is small, so that the temperature difference between the opening forming region and the liquid film forming region is small. Become. Therefore, the treatment liquid is in an equilibrium state in which the movement to the inside and the movement to the outside of the substrate are repeated. In this case, when the treatment liquid returns to the inside of the substrate, the treatment liquid may come into direct contact with the upper surface of the substrate from which the vapor phase layer has been lost. Therefore, there is a possibility that the pattern collapses due to the surface tension of the treatment liquid and particles are generated due to poor drying.

The substrate is rotating as it expands the opening. Therefore, this equilibrium state can be eliminated if the centrifugal force acting on the liquid film is sufficiently large. However, if the centrifugal force is not large enough, the equilibrium state will not be resolved.
Therefore, if the configuration is such that when the inner peripheral edge of the liquid film reaches the peripheral edge of the upper surface of the substrate, gas is blown to the inside of the inner peripheral edge of the liquid film on the upper surface of the substrate, the treatment liquid is sprayed with the force of the gas. You can push it outwards to enlarge the opening. As a result, the treatment liquid is removed from the upper surface of the substrate without stopping. It is possible to suppress or prevent pattern collapse and particle generation.

In one embodiment of the present invention, in the opening forming step, the opening is formed with the height position of the irradiation unit set to a separated position. In the substrate processing method, in the irradiation unit proximity step of changing the height position of the irradiation unit to a position closer to the upper surface of the substrate than the separation position after the opening is formed, and in the opening expansion step. A proximity movement step of moving the irradiation region toward the peripheral edge of the substrate by moving the irradiation unit toward the peripheral edge of the substrate while maintaining the height position of the irradiation unit at the proximity position. Including further.

According to this method, the height position of the irradiation unit is changed from the separated position to the close position after the opening is formed. Therefore, the temperature of the opening forming region can be rapidly raised. As a result, the opening can be enlarged by utilizing the temperature difference. After that, when the opening is enlarged, the irradiation unit whose height position is maintained at a close position is moved to the peripheral portion. Therefore, the opening can be enlarged while giving a sufficient amount of heat to the inner peripheral edge of the liquid film.

In one embodiment of the present invention, the light emitted from the irradiation unit has a wavelength that allows the processing liquid to pass through. Therefore, the light can reach the upper surface of the substrate satisfactorily. When the treatment liquid is IPA, the wavelength transmitted through the treatment liquid is 200 nm to 1100 nm.
Another embodiment of the present invention includes a substrate holding unit that holds the substrate horizontally, a processing liquid supply unit that supplies the processing liquid to the upper surface of the substrate that is held horizontally, and the entire substrate that is held horizontally. Is configured to face the upper surface of the substrate held horizontally with a substrate heating unit that heats the substrate to a temperature lower than the boiling point of the treatment liquid, and irradiates light toward the center of the upper surface of the substrate. An irradiation unit, a moving unit that moves the irradiation unit in the horizontal direction, and a substrate rotation unit that rotates the substrate around a rotation axis extending in the vertical direction through the central portion of the upper surface of the substrate held horizontally. Provided is a substrate processing apparatus including the processing liquid supply unit, the substrate heating unit, the irradiation unit, the moving unit, and a controller for controlling the substrate rotating unit.

Then, the controller supplies the treatment liquid from the treatment liquid supply unit to the upper surface of the substrate held by the substrate holding unit, thereby forming a liquid film of the treatment liquid on the upper surface of the substrate. While executing the step, the liquid film heat retaining step of keeping the liquid film warm by heating the entire substrate by the substrate heating unit, and the liquid film heat retaining step, the irradiation region set on the upper surface of the substrate is formed. By irradiating light from the irradiation unit toward the substrate, the treatment liquid in contact with the central portion of the upper surface of the substrate is evaporated, and the gas phase layer in contact with the upper surface of the substrate and holding the treatment liquid is formed on the liquid film. A vapor phase layer forming step formed in the central portion of the above, an opening forming step of eliminating the treatment liquid held by the vapor phase layer and forming an opening in the central portion of the liquid film, and the substrate rotating unit By moving the irradiation unit to the moving unit and moving the irradiation region toward the peripheral edge of the substrate while executing the substrate rotation step of rotating the substrate, the liquid film heat retention step, and the substrate rotation step. , The opening expansion step of expanding the opening while maintaining the state in which the vapor phase layer is formed on the inner peripheral edge of the liquid film is programmed.

According to this apparatus, the same effect as the above-described substrate processing method is obtained.

FIG. 1 is a schematic plan view showing the layout of the substrate processing apparatus according to the first embodiment of the present invention. FIG. 2 is an enlarged view of a cross section of the surface of the substrate to be processed. FIG. 3 is a schematic partial cross-sectional view showing a schematic configuration of a processing unit provided in the substrate processing apparatus. FIG. 4 is a vertical cross-sectional view of the lamp unit provided in the processing unit. FIG. 5 is a view of the lamp unit as viewed from below. FIG. 6 is a block diagram showing an electrical configuration of a main part of the substrate processing apparatus. FIG. 7 is a flow chart for explaining an example of substrate processing by the substrate processing apparatus. FIG. 8A is a schematic view for explaining the state of the substrate processing. FIG. 8B is a schematic view for explaining the state of the substrate processing. FIG. 8C is a schematic view for explaining the state of the substrate processing. FIG. 8D is a schematic diagram for explaining the state of the substrate processing. FIG. 8E is a schematic view for explaining the state of the substrate processing. FIG. 8F is a schematic view for explaining the state of the substrate processing. FIG. 9A is a schematic view for explaining a region formed on the upper surface of the substrate during the substrate processing. FIG. 9B is a schematic view for explaining a region formed on the upper surface of the substrate during the substrate processing. FIG. 9C is a schematic view for explaining a region formed on the upper surface of the substrate during the substrate processing. FIG. 9D is a schematic view for explaining a region formed on the upper surface of the substrate during the substrate processing. FIG. 10 is a vertical cross-sectional view of an irradiation unit provided in the substrate processing apparatus according to the second embodiment of the present invention. FIG. 11 is a bottom view of the irradiation unit provided in the substrate processing apparatus according to the second embodiment. FIG. 12A is a schematic view for explaining a state of substrate processing by the substrate processing apparatus according to the second embodiment. FIG. 12B is a schematic view for explaining a state of substrate processing by the substrate processing apparatus according to the second embodiment. FIG. 12C is a schematic view for explaining a state of substrate processing by the substrate processing apparatus according to the second embodiment. FIG. 12D is a schematic view for explaining a state of substrate processing by the substrate processing apparatus according to the second embodiment. FIG. 13 is a schematic partial cross-sectional view showing a schematic configuration of a processing unit provided in the substrate processing apparatus according to the third embodiment of the present invention. FIG. 14A is a schematic view for explaining a state of substrate processing by the substrate processing apparatus according to the third embodiment. FIG. 14B is a schematic view for explaining a state of substrate processing by the substrate processing apparatus according to the third embodiment. FIG. 14C is a schematic view for explaining a state of substrate processing by the substrate processing apparatus according to the third embodiment. FIG. 14D is a schematic view for explaining a state of substrate processing by the substrate processing apparatus according to the third embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
<First Embodiment>
FIG. 1 is a schematic plan view showing the layout of the substrate processing apparatus 1 according to the first embodiment of the present invention.
The substrate processing device 1 is a single-wafer type device that processes substrates W such as silicon wafers one by one. In this embodiment, the substrate W is a disk-shaped substrate.

The substrate processing apparatus 1 includes a load port LP on which a plurality of processing units 2 for processing the substrate W with a fluid, a carrier C accommodating a plurality of substrates W processed by the processing unit 2, and a load port LP are mounted. It includes transfer robots IR and CR that transfer the substrate W between the substrate processing unit 2 and the processing unit 2, and a controller 3 that controls the substrate processing apparatus 1.
The transfer robot IR transfers the substrate W between the carrier C and the transfer robot CR. The transfer robot CR transfers the substrate W between the transfer robot IR and the processing unit 2. The plurality of processing units 2 have, for example, a similar configuration.

Each processing unit 2 includes a chamber 4 and a processing cup 7 arranged in the chamber 4, and processes the substrate W in the processing cup 7. A doorway 4A for loading / unloading the substrate W and unloading the substrate W is formed in the chamber 4 by the transfer robot CR. The chamber 4 is provided with a shutter unit 4B that opens and closes the doorway 4A.

As shown in FIG. 2, a fine uneven pattern 160 is formed on the surface layer of the substrate W processed by the substrate processing apparatus 1. The uneven pattern 160 includes a fine convex structure 161 formed on the surface of the substrate W and a concave portion (groove) 162 formed between adjacent structures 161.
The surface of the uneven pattern 160, that is, the surface of the structure 161 (convex portion) and the concave portion 162 forms the uneven pattern surface 165. The pattern surface 165 is included in the surface of the substrate W. The surface 161a of the structure 161 is composed of a front end surface 161b (top) and a side surface 161c, and the surface of the recess 162 is composed of a bottom surface 162a (bottom). When the structure 161 has a cylindrical shape, a recess is formed in the structure 161.

The structure 161 may include an insulator film or a conductor film. Further, the structure 161 may be a laminated film in which a plurality of films are laminated.
The uneven pattern 160 is a fine pattern having an aspect ratio of 3 or more. The aspect ratio of the uneven pattern 160 is, for example, 10 to 50. The width L1 of the structure 161 may be about 5 nm to 45 nm, and the distance L2 between the structures 161 may be about 5 nm to several μm. The height of the structure 161 (pattern height T1) may be, for example, about 50 nm to 5 μm. The pattern height T1 is the distance between the front end surface 161b of the structure 161 and the bottom surface 162a (bottom portion) of the recess 162.

FIG. 3 is a schematic diagram for explaining a configuration example of the processing unit 2. The processing unit 2 includes a spin chuck 5, a heater unit 6, a processing cup 7, a chemical liquid nozzle 8, a rinse liquid nozzle 9, a low surface tension liquid nozzle 10, a gas nozzle 11, and a lamp unit 12. ..
The spin chuck 5 rotates the substrate W around the rotation axis A1 while holding the substrate W horizontally. The rotation axis A1 passes through the center position of the upper surface (upper surface) of the substrate W and extends in the vertical direction. The spin chuck 5 includes a plurality of chuck pins 20, a spin base 21, a rotating shaft 22, and a spin motor 23 that applies a rotational force to the rotating shaft 22. The spin chuck 5 is an example of a substrate holding rotation unit.

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

The spin base 21 and the plurality of chuck pins 20 form a substrate holding unit that holds the substrate W horizontally. The board holding unit is also called a board holder.
The rotating shaft 22 extends in the vertical direction along the rotating axis A1. The upper end of the rotating 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 rotating shaft 22. The spin base 21 is rotated by rotating the rotating shaft 22 by the spin motor 23. As a result, the substrate W is rotated around the rotation axis A1. The spin motor 23 is an example of a substrate rotation unit that rotates the substrate W around 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 arranged between the upper surface of the spin base 21 and the lower surface of the substrate W. The heater unit 6 has a facing surface 6a facing 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 in the plate body 61. By energizing the heater 62, the facing surface 6a is heated. The facing surface 6a is heated to, for example, 195 ° C. Then, electric power is supplied to the heater 62 from the heater energizing unit 64 via the feeding line 63.

The processing unit 2 includes a heater elevating unit 65 that elevates and elevates the heater unit 6 relative to the spin base 21. The heater elevating unit 65 includes, for example, a ball screw mechanism (not shown) and an electric motor (not shown) that applies a driving force to the ball screw mechanism. The heater elevating unit 65 is also referred to as a heater lifter.
An elevating shaft 66 extending in the vertical direction along the rotation axis A1 is coupled to the lower surface of the heater unit 6. The elevating shaft 66 inserts a through hole 21a formed in the central portion of the spin base 21 and a hollow rotating shaft 22. A feeder line 63 is passed through the elevating shaft 66.

The heater elevating unit 65 raises and lowers the heater unit 6 via the elevating shaft 66. The heater unit 6 can be raised and lowered by the heater raising and lowering unit 65 to be positioned at the lower position and the upper position. The heater elevating unit 65 can be arranged not only in the lower and upper positions but also in any position between the lower and upper positions.
The processing cup 7 is a member that receives the liquid scattered outward from the substrate W held by the spin chuck 5 and collects or discards the liquid. The processing cup 7 includes a plurality of guards 71 that receive the liquid scattered outward from the substrate W held by the spin chuck 5, a plurality of cups 72 that receive the liquid guided downward by the plurality of guards 71, and a plurality of cups 72. Includes a cylindrical outer wall member 73 that surrounds the guard 71 and the plurality of cups 72.

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

The first guard 71A is arranged so as to surround the spin base 21. The second guard 71B is arranged so as to surround the spin base 21 outside 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 side.

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

When both the first guard 71A and the second guard 71B are located in the upper position, the liquid scattered from the substrate W is received by the first guard 71A. When the first guard 71A is located in the lower position and the second guard 71B is located in the upper position, the liquid scattered from the substrate W is received by the second guard 71B.
When both the first guard 71A and the second guard 71B are located at the lower positions, the transfer robot CR can carry the substrate W into the chamber 4 and carry out the substrate W from the chamber 4.

The guard elevating unit 74 includes, for example, a first ball screw mechanism (not shown) coupled to the first guard 71A, a first motor (not shown) that applies a driving force to the first ball screw mechanism, and a second. It includes a second ball screw mechanism (not shown) coupled to the guard 71B and a second motor (not shown) that applies a driving force to the second ball screw mechanism. The guard elevating unit 74 is an example of a guard moving unit. The guard elevating unit 74 is also referred to as a guard lifter.

The chemical solution nozzle 8 is a nozzle that discharges the chemical solution toward the upper surface of the substrate W. The chemical solution nozzle 8 is connected to a chemical solution pipe 40 that guides the chemical solution to the chemical solution nozzle 8. When the chemical solution valve 50 interposed in the chemical solution pipe 40 is opened, the chemical solution is discharged downward from the discharge port of the chemical solution nozzle 8 in a continuous flow.
As the chemical solution, for example, sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid (HF, DHF), phosphoric acid, acetic acid, aqueous ammonia, hydrogen peroxide solution, organic acid (for example, citric acid, oxalic acid, etc.), organic alkali (for example, TMAH: A liquid containing at least one of (tetramethylammonium hydrochloride, etc.), a surfactant, and an antioxidant can be used.

The chemical solution nozzle 8 is, for example, a movable scan nozzle. The processing unit 2 further includes a first arm 30 to which the chemical solution nozzle 8 is attached to the tip end portion, and a first moving unit 31 that moves the chemical solution nozzle 8 by moving the first arm 30.
By rotating the first arm 30, the first moving unit 31 horizontally moves the chemical solution nozzle 8 along a trajectory passing through the central portion of the upper surface of the substrate W in a plan view. The first moving unit 31 horizontally moves the chemical solution nozzle 8 between the central position and the retracted position. When the chemical solution nozzle 8 is located at the center position, the chemical solution nozzle 8 faces the central portion of the upper surface of the substrate W.

The central portion of the upper surface of the substrate W is a region including a rotation center position of the upper surface of the substrate W and a position around the rotation center position on the upper surface of the substrate W.
When the chemical solution nozzle 8 is located at the retracted position, the chemical solution nozzle 8 retracts around the spin chuck 5 in a plan view. The first moving unit 31 includes, for example, a rotating shaft (not shown) connected to the first arm 30 and extending in the vertical direction, and an electric motor (not shown) for rotating the rotating shaft.

The rinse solution nozzle 9 is a nozzle that discharges the rinse solution for washing away the chemical solution toward the upper surface of the substrate W. The rinse liquid nozzle 9 is connected to a rinse liquid pipe 41 that guides the rinse liquid to the rinse liquid nozzle 9. When the rinse liquid valve 51 interposed in the rinse liquid pipe 41 is opened, the rinse liquid is discharged downward from the discharge port of the rinse liquid nozzle 9 in a continuous flow.
The rinsing liquid is, for example, pure water (deionized water: DIW (Deionized Water)). The rinse solution is either carbonated water, electrolytic ionized water, hydrogen water, ozone water, hydrochloric acid water having a dilution concentration (for example, about 10 ppm to 100 ppm), and ammonia water having a dilution concentration (for example, about 10 ppm to 100 ppm). You may.

The rinse liquid nozzle 9 is, for example, a movable scan nozzle. The processing unit 2 further includes a second arm 32 to which the rinsing liquid nozzle 9 is attached to the tip end portion, and a second moving unit 33 that moves the rinsing liquid nozzle 9 by moving the second arm 32.
By rotating the second arm 32, the second moving unit 33 horizontally moves the rinse liquid nozzle 9 along a trajectory passing through the central portion of the upper surface of the substrate W in a plan view. The second moving unit 33 horizontally moves the rinse liquid nozzle 9 between the central position and the retracted position. When the rinse liquid nozzle 9 is located at the center position, the rinse liquid nozzle 9 faces the central portion of the upper surface of the substrate W. When the rinse liquid nozzle 9 is located at the retracted position, the rinse liquid nozzle 9 retracts around the spin chuck 5 in a plan view. The second moving unit 33 includes, for example, a rotating shaft (not shown) connected to the second arm 32 and extending in the vertical direction, and an electric motor (not shown) for rotating the rotating shaft.

The low surface tension liquid nozzle 10 is a nozzle that discharges a low surface tension liquid having a lower surface tension than the rinse liquid toward the upper surface of the substrate W. The low surface tension liquid nozzle 10 is connected to a low surface tension liquid pipe 42 that guides the low surface tension liquid to the low surface tension liquid nozzle 10. When the low surface tension liquid valve 52 interposed in the low surface tension liquid pipe 42 is opened, the low surface tension liquid is discharged downward from the discharge port 10a of the low surface tension liquid nozzle 10 in a continuous flow.

The low surface tension liquid is an organic solvent such as IPA. The surface tension of IPA is lower than the surface tension of water. Organic solvents other than IPA can also be used as low surface tension liquids. In addition to IPA, organic solvents such as methanol, ethanol, acetone, EG (ethylene glycol), HFE (hydrofluoroether), n-butanol, t-butanol, isobutyl alcohol and 2-butanol are also low surface tension liquids. Can be used as.

Not only those composed of simple substances but also organic solvents mixed with other components can be used as low surface tension liquids. The low surface tension liquid is an example of a treatment liquid, and the low surface tension liquid nozzle 10 is an example of a treatment liquid supply unit.
The gas nozzle 11 is a nozzle that discharges gas toward the upper surface of the substrate W. The gas nozzle 11 is connected to a gas pipe 43 that guides the gas to the gas nozzle 11. A gas valve 53A and a gas flow rate adjusting valve 53B are interposed in the gas pipe 43. When the gas valve 53A is opened, gas is continuously discharged downward from the discharge port 11a of the gas nozzle 11 at a flow rate corresponding to the opening degree of the gas flow rate adjusting valve 53B.

The gas supplied to the gas nozzle 11 is an inert gas such as nitrogen gas. The inert gas is not limited to nitrogen gas, and rare gases such as helium gas and argon gas can be used as the inert gas.
The lamp unit 12 is a unit that heats the substrate W by irradiating (emitting) light toward the upper surface of the substrate W. The lamp unit 12 is an example of an irradiation unit. The lamp unit 12 irradiates the substrate W with light containing at least one of near infrared rays, visible rays, and ultraviolet rays, and heats the substrate W by radiation. That is, the lamp unit 12 is a radiant heating heater. Electric power is supplied to the lamp unit 12 from the lamp energizing unit 90 via the feeder line 89.

The low surface tension liquid nozzle 10 and the gas nozzle 11 are attached to the lamp unit 12. The processing unit 2 further includes a third arm 34 to which the lamp unit 12 is attached to the tip end portion, and a third moving unit 35 (moving unit) that moves the lamp unit 12 by moving the third arm 34. ..
By moving the third arm 34, the low surface tension liquid nozzle 10 and the gas nozzle 11 move together with the lamp unit 12. The low surface tension liquid nozzle 10 and the gas nozzle 11 are movable scan nozzles.

The third moving unit 35 rotates the third arm 34 to rotate the low surface tension liquid nozzle 10, the gas nozzle 11, and the lamp unit 12 along a trajectory passing through the central portion of the upper surface of the substrate W in a plan view. Move horizontally.
The third moving unit 35 can arrange the low surface tension liquid nozzle 10, the gas nozzle 11, and the lamp unit 12 at the retracted position and the center position. The low surface tension liquid nozzle 10, the gas nozzle 11, and the lamp unit 12 retract around the spin chuck 5 in a plan view when they are located in the retracted position.

When the low surface tension liquid nozzle 10 is located at the center position, the discharge port 10a of the low surface tension liquid nozzle 10 faces the central portion of the upper surface of the substrate W. When the gas nozzle 11 is located at the center position, the discharge port 11a of the gas nozzle 11 faces the central portion of the upper surface of the substrate W. When the lamp unit 12 is located at the center position, the lamp unit 12 faces the central portion of the upper surface of the substrate W.

The third moving unit 35 includes, for example, a rotating shaft (not shown) connected to the third arm 34 and extending in the vertical direction, and an electric motor (not shown) for rotating the rotating shaft.
FIG. 4 is a vertical cross-sectional view of the lamp unit 12. FIG. 5 is a view of the lamp unit 12 as viewed from below. The lamp unit 12 includes a lamp 80, a lamp housing 81 accommodating the lamp 80, and a heat sink 82 for cooling the inside of the lamp housing 81.

The lamp 80 includes a disk-shaped lamp substrate 83 and a plurality of (59 in the example of FIG. 5) light sources 84 mounted on the lower surface of the lamp substrate 83. The individual light sources 84 are, for example, LEDs (light emitting diodes). A plurality of light sources 84 are turned on by the electric power supplied from the lamp energizing unit 90.
As shown in FIG. 5, the plurality of light sources 84 are dispersedly arranged over the entire lower surface of the lamp substrate 83. In the example of FIG. 5, one light source 84 is arranged at the center of the lower surface of the lamp substrate 83, and the remaining 58 light sources 84 are quadruple annular so as to surround the center of the lower surface of the lamp substrate 83. Is located in. The arrangement density of the light source 84 on the lamp substrate 83 is substantially uniform. The plurality of light sources 84 constitute a circular light emitting portion 12a that spreads in the horizontal direction.

The light emitted from the individual light sources 84 includes at least one of near infrared, visible and ultraviolet. The wavelength of light emitted from each light source 84 is 200 nm or more and 1100 nm or less. The light emitted from the individual light sources 84 preferably has a wavelength of 390 nm or more and 800 nm or less.
As shown in FIG. 4, the lamp housing 81 includes a cylindrical housing body 85 and a disk-shaped bottom wall 86. The housing body 85 is made of a chemical resistant material such as PTFE (polytetrafluoroethylene). The bottom wall 86 is made of a light-transmitting and heat-resistant material such as quartz. The lamp housing 81 is smaller than the substrate W in a plan view. The lower surface of the bottom wall 86 constitutes the lower surface of the lamp unit 12.

The heat sink 82 includes a heat sink body 87 and a cooling unit 88 that supplies a cooling fluid to the heat sink body 87 to cool the heat sink body 87. The heat sink body 87 is formed in a container shape using a metal having high heat transfer characteristics (for example, aluminum, iron, copper, etc.). The cooling unit 88 includes a refrigerant supply source 88a, a refrigerant supply pipe 88b that supplies the refrigerant from the refrigerant supply source 88a to the heat sink main body 87, and a refrigerant return pipe 88c that returns the refrigerant supplied to the heat sink main body 87 to the refrigerant supply source 88a. Includes a pump 88d that delivers the refrigerant in the refrigerant supply pipe 88b.

The cooling unit 88 supplies a refrigerant such as cooling water to the heat sink main body 87. That is, the heat sink 82 is a water-cooled heat sink. The lamp 80 and its surroundings are heated as the plurality of light sources 84 emit light. However, since the inside of the lamp housing 81 is cooled by the heat sink 82, it is possible to prevent the inside of the lamp housing 81 from being excessively heated. In the heat sink 82, a cooling gas may be used as the refrigerant.

The lamp unit 12 is used in a state where a liquid film L of a low surface tension liquid covering the upper surface of the substrate W is formed on the upper surface of the substrate W. The low surface tension liquid nozzle 10 and the gas nozzle 11 are attached to the outer wall surface 81a of the lamp housing 81 in a vertical direction.
As shown in FIG. 4, when the lamp 80 emits light, that is, when a plurality of light sources 84 emit light, the light emitted from the lamp 80 (light including at least one of near infrared rays, visible rays, and ultraviolet rays) is the lamp. It passes through the bottom wall 86 of the housing 81 and irradiates the upper surface of the substrate W.

IPA, which is an example of a low surface tension liquid, transmits light having a wavelength of 200 nm or more and 1100 nm or less. The wavelength of the light emitted from the lamp 80 is 200 nm or more and 1100 nm or less (more preferably, 390 nm or more and 800 nm or less). Therefore, the light emitted from the lamp 80 is not absorbed by the liquid film L but passes through the liquid film L.
The light radiated from the outer surface of the lamp housing 81 (the lower surface of the bottom wall 86) passes through the liquid film L and irradiates the upper surface of the substrate W. The region on the upper surface of the substrate W where the light is irradiated from the lamp unit 12 is referred to as an irradiation region RR. As a result, the irradiation region RR is heated by radiation to raise the temperature. The irradiation region RR coincides with the heating region heated by the light emitted from the lamp unit 12 in a plan view.

The temperature of the surface layer of the substrate W (specifically, the uneven pattern 160 shown in FIG. 2) rises due to the light emitted from the lamp unit 12. By irradiating light, the temperature of the surface layer of the substrate W is heated to a temperature equal to or higher than the boiling point of the low surface tension liquid, so that the low surface tension liquid in contact with the irradiation region RR is warmed and evaporated. As a result, a gas phase layer of a low surface tension liquid is formed around the surface of the substrate W (the pattern surface 165 shown in FIG. 2). When the low surface tension liquid is IPA, the boiling point is 82.6 ° C.

When the irradiation region RR is set on the upper surface of the substrate W, the third moving unit 35 moves the lamp unit 12 horizontally, so that the irradiation region RR moves within the upper surface of the substrate W.
FIG. 6 is a block diagram showing an electrical configuration of a main part of the substrate processing apparatus 1. The controller 3 includes a microcomputer and controls a control target 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 a control program.
In particular, the controller 3 includes a transfer robot IR, CR, a spin motor 23, a first moving unit 31, a second moving unit 33, a third moving unit 35, a guard elevating unit 74, a pin opening / closing unit 24, a heater energizing unit 64, and a heater. It is programmed to control an elevating unit 65, a lamp energizing unit 90, a pump 88d, a chemical solution valve 50, a rinse solution valve 51, a low surface tension liquid valve 52, a gas valve 53A, and a gas flow rate adjusting valve 53B.

By controlling the valve by the controller 3, the presence or absence of liquid or gas discharge from the corresponding nozzle and the discharge flow rate of the gas from the corresponding nozzle are controlled.
FIG. 7 is a flow chart for explaining an example of substrate processing by the substrate processing apparatus 1. FIG. 7 mainly shows the processing realized by the controller 3 executing the program. 8A to 8F are schematic views for explaining a state of substrate processing. 9A to 9D are schematic views for explaining a region formed on the upper surface of the substrate W during substrate processing. In the following, FIGS. 3 and 7 will be mainly referred to, and FIGS. 8A to 9D will be referred to as appropriate.

In the substrate processing by the substrate processing apparatus 1, for example, as shown in FIG. 7, a substrate loading step (step S1), a chemical liquid supply step (step S2), a rinse liquid supply step (step S3), a replacement step (step S4), The liquid film forming step (step S5), the gas phase layer forming step (step S6), the liquid film removing step (step S7), and the substrate unloading step (step S8) are executed.

First, the unprocessed substrate W is carried into the processing unit 2 from the carrier C by the transfer robot CR and passed to the spin chuck 5 (step S1). As a result, the substrate W is held horizontally by the spin chuck 5 (substrate holding step). The substrate W is held in a posture in which the surface on which the uneven pattern 160 (see FIG. 2) is formed is the upper surface. When the substrate W is carried in, electric power is supplied to the heater unit 6, and the heater unit 6 is retracted to a lower position. When the board W is carried in, a plurality of guards 71 are retracted to lower positions. When the substrate W is brought in, power is not supplied to the lamp unit 12.

When the substrate W is held by the spin chuck 5, the spin motor 23 rotates the spin base 21. As a result, the horizontally held substrate W is rotated (substrate rotation step). The holding of the substrate W by the spin chuck 5 and the rotation of the substrate W by the spin motor 23 are continued until the liquid film removing step (step S7) is completed. The guard elevating unit 74 has the first guard 71A and the second guard 71A so that at least one guard 71 is located at the upper position from the start of the substrate holding step to the end of the liquid film removing step (step S7). Adjust the height position of the guard 71B.

Next, after the transfer robot CR retracts to the outside of the processing unit 2, a chemical solution supply step (step S2) of supplying the chemical solution to the upper surface of the substrate W in order to treat the upper surface of the substrate W with the chemical solution is started. Specifically, the first moving unit 31 moves the chemical solution nozzle 8 to the chemical solution processing position. The chemical treatment position is, for example, the central position. The chemical solution valve 50 is opened with the chemical solution nozzle 8 located at the chemical solution processing position. As a result, the chemical solution is supplied (discharged) from the chemical solution nozzle 8 toward the central portion of the upper surface of the rotating substrate W (chemical solution supply step, chemical solution discharge step).

The chemical solution discharged from the chemical solution nozzle 8 lands on the central portion of the upper surface of the substrate W. Centrifugal force due to the rotation of the substrate W acts on the chemical solution deposited on the upper surface of the substrate W. Therefore, the chemical solution is spread over the entire upper surface of the substrate W by centrifugal force, whereby the entire upper surface of the substrate W is treated by the chemical solution.
The supply of the chemical solution from the chemical solution nozzle 8 is continued for a predetermined time, for example, 60 seconds. In the chemical solution supply step, the substrate W is rotated at a predetermined chemical solution rotation speed, for example, 1000 rpm.

After the chemical treatment for a predetermined time, the rinsing treatment (step S2) in which the upper surface of the substrate W is treated with the rinsing liquid is started. Specifically, the chemical solution valve 50 is closed, and the first moving unit 31 moves the chemical solution nozzle 8 to the retracted position. After the movement of the chemical liquid nozzle 8 is started, the second moving unit 33 moves the rinsing liquid nozzle 9 to the rinsing treatment position. The rinsing position is, for example, the central position.

The rinse liquid valve 51 is opened with the rinse liquid nozzle 9 located at the rinse processing position. As a result, the rinse liquid is supplied (discharged) from the rinse liquid nozzle 9 toward the central portion of the upper surface of the rotating substrate W (rinse liquid supply step, rinse liquid discharge step).
The rinse liquid discharged from the rinse liquid nozzle 9 lands on the central portion of the upper surface of the substrate W. Centrifugal force due to the rotation of the substrate W acts on the rinse liquid that has landed on the upper surface of the substrate W. Therefore, the rinse solution is spread over the entire upper surface of the substrate W by centrifugal force, whereby the chemical solution existing on the upper surface of the substrate W is replaced with the rinse solution. That is, the entire upper surface of the substrate W is treated with the rinsing liquid.

The supply of the rinse liquid from the rinse liquid nozzle 9 is continued for a predetermined time, for example, 15 seconds. In the rinse liquid supply step, the substrate W is rotated at a predetermined rinse liquid rotation speed, for example, 1000 rpm.
After the rinsing treatment for a predetermined time, a replacement step (step S4) of replacing the rinsing liquid existing on the upper surface of the substrate W with a low surface tension liquid is executed.

In the replacement step, first, the rinse liquid valve 51 is closed, and the second moving unit 33 moves the rinse liquid nozzle 9 to the retracted position. After the movement of the rinse liquid nozzle 9 is started, the third moving unit 35 moves the low surface tension liquid nozzle 10 to the low surface tension liquid processing position. The low surface tension liquid treatment position is, for example, the central position.
The low surface tension liquid valve 52 is opened with the low surface tension liquid nozzle 10 located at the low surface tension liquid processing position. As a result, as shown in FIG. 8A, the supply (discharge) of the low surface tension liquid from the low surface tension liquid nozzle 10 is started, and the low surface tension liquid is supplied toward the central portion of the upper surface of the substrate W ( Low surface tension liquid supply process, low surface tension liquid discharge process).

The low surface tension liquid discharged from the low surface tension liquid nozzle 10 lands on the central portion of the upper surface of the substrate W. Centrifugal force due to the rotation of the substrate W acts on the low surface tension liquid that has landed on the upper surface of the substrate W. Therefore, the low surface tension liquid spreads over the entire upper surface of the substrate W by centrifugal force, whereby the rinsing liquid existing on the upper surface of the substrate W is replaced with the low surface tension liquid, and the entire upper surface of the substrate W has a low surface. Covered by tension liquid.

The rotation of the substrate W is decelerated to a predetermined replacement rate at the same time as the start of the supply of the low surface tension liquid or during the supply of the low surface tension liquid (first rotation deceleration step). The replacement rate is, for example, 300 rpm.
During the supply of the low surface tension liquid, the heater elevating unit 65 moves the heater unit 6 from the lower position to the first heating position. The first heating position is a position above the lower position and separated from the substrate W. When the heater unit 6 is located at the first heating position, the facing surface 6a of the heater unit 6 approaches the lower surface of the substrate W in a non-contact manner. By arranging the heater unit 6 at the first heating position, heating of the substrate W is started. When the heater unit 6 is located at the first heating position, the distance between the lower surface of the substrate W and the facing surface 6a of the heater unit 6 is, for example, 4 mm. With the heater unit 6 arranged at the first heating position, the substrate W is heated to, for example, 30 ° C.

After the rinse liquid existing on the upper surface of the substrate W is replaced with the low surface tension liquid, the supply of the low surface tension liquid is continued, and the liquid film L of the low surface tension liquid is applied to the upper surface of the substrate W (see FIG. 8B). The liquid film forming step (step S5) for forming the above is executed.
After the rinse liquid existing on the upper surface of the substrate W is replaced with the low surface tension liquid, the rotation of the substrate W is decelerated to a predetermined liquid film forming speed (second rotation deceleration step). The liquid film formation rate is greater than 0 rpm and less than 50 rpm, for example, 10 rpm. In the second rotation deceleration step, the rotation of the substrate W may be decelerated stepwise.

The low surface tension liquid valve 52 is closed after the rotation of the substrate W is decelerated to the liquid film formation rate. As a result, the supply of the low surface tension liquid from the low surface tension liquid nozzle 10 to the upper surface of the substrate W is stopped. The supply of the low surface tension liquid from the low surface tension liquid nozzle 10 is continued for a predetermined time, for example, 30 seconds.
By decelerating the rotation of the substrate W to the liquid film forming speed, the centrifugal force acting on the low surface tension liquid on the substrate W becomes small. Therefore, the discharge of the low surface tension liquid from the substrate W is stopped. Alternatively, the low surface tension liquid is removed from the substrate W in a very small amount. Therefore, even after the supply of the low surface tension liquid to the upper surface of the substrate W is stopped, the upper surface of the substrate W is maintained in a state of being covered with the low surface tension liquid. As shown in FIG. 8B, the supply of the low surface tension liquid is stopped in a state where the rotation of the substrate W is decelerated to the liquid film formation rate, so that the low surface tension liquid on the substrate W is sufficiently thickened and the paddle. The liquid film L in the state is formed (liquid film forming step, paddle forming step).

Even if a small amount of the rinsing liquid remains in the recess 162 of the uneven pattern 160 after the rinsing liquid is replaced with the low surface tension liquid (see FIG. 2), the rinsing liquid dissolves in the low surface tension liquid and is a liquid film. Diffuses in L. As a result, the amount of rinsing liquid remaining in the recess 162 of the concave-convex pattern 160 can be reduced.
After the liquid film L is formed on the upper surface of the substrate W, the substrate W is heated by irradiating light from the lamp unit 12, and the vapor phase layer VL (see the enlarged view of FIG. 8C) is located at the center of the upper surface of the substrate W. ) Is formed (step S6).

As shown in FIG. 8C, the heater elevating unit 65 raises the heater unit 6 and arranges it at the second heating position in a state where the liquid film L is formed on the upper surface of the substrate W. The second heating position is a position above the first heating position and separated from the substrate W. When the heater unit 6 is located at the second heating position, the facing surface 6a of the heater unit 6 approaches the lower surface of the substrate W in a non-contact manner. When the heater unit 6 is located at the second heating position, the distance between the lower surface of the substrate W and the facing surface 6a of the heater unit 6 is, for example, 2 mm.

By arranging the heater unit 6 at the second heating position, the entire substrate W is heated to a temperature higher than room temperature (for example, 25 ° C.) and lower than the boiling point of the low surface tension liquid (heater heating step). .. Therefore, the liquid film L is kept at a temperature higher than room temperature (for example, 25 ° C.) and lower than the boiling point of the low surface tension liquid (liquid film heat retaining step). The substrate W is heated to a higher temperature when the heater unit 6 is located at the second heating position than when the heater unit 6 is located at the first heating position. If the facing surface 6a of the heater unit 6 is heated to 195 ° C. while the heater unit 6 is arranged at the second heating position, the substrate W is heated to 40 ° C.

With the liquid film L formed on the upper surface of the substrate W, the third moving unit 35 moves the lamp unit 12 in the horizontal direction and arranges it at the light irradiation position. The light irradiation position is, for example, the central position. Further, the third moving unit 35 moves the lamp unit 12 in the vertical direction so that the height position of the lamp unit 12 becomes a separated position. When the lamp unit 12 is located at a remote position, the distance between the lower surface of the lamp unit 12 and the upper surface of the substrate W is, for example, 50 mm.

The lamp energizing unit 90 energizes the lamp unit 12 in a state where the height position of the lamp unit 12 is the separated position. As a result, irradiation of light from the lamp unit 12 is started (light irradiation step). Light irradiation is started while performing the liquid film heat retention step. The irradiation of light is started immediately (for example, 1.5 seconds later) after the liquid film L in the paddle state is formed.

The light emitted from the lamp unit 12 is not absorbed by the liquid film L, but passes through the liquid film L and is irradiated to the irradiation region RR set in the central portion of the upper surface of the substrate W. As a result, the central portion of the upper surface of the substrate W is heated by radiation. As a result, the low surface tension liquid in contact with the irradiation region RR is warmed.
When the temperature of the irradiation region RR (that is, the temperature of the uneven pattern 160 in the irradiation region RR) is equal to or higher than the boiling point of the low surface tension liquid, the low surface tension liquid evaporates at the interface between the liquid film L and the substrate W. .. By evaporating the low surface tension liquid in contact with the uneven pattern 160 in the irradiation region RR, a gas phase layer VL of the low surface tension liquid (see the enlarged view of FIG. 8C) is formed between the liquid film L and the substrate W. Will be done. As a result, the liquid film L is held by the vapor phase layer VL in the irradiation region RR and floats from the upper surface of the substrate W.

If the temperature of the surface layer of the substrate W in the irradiation region RR is heated to a vapor phase formation temperature equal to or higher than the boiling point of the low surface tension liquid, a vapor phase layer VL having a sufficient thickness is formed in the irradiation region RR. When the low surface tension liquid is IPA, the boiling point is 82.6 ° C. and the vapor phase layer formation temperature is, for example, 100 ° C. Sufficient thickness means a thickness larger than the pattern height T1. If a gas phase layer having a sufficient thickness is formed, the liquid film L can be maintained at a sufficient height position by the gas phase layer. The sufficient height position is a position where the interface between the liquid film L and the gas phase layer VL is located above the tip surface 161b (see also FIG. 2) of the structure 161 of the uneven pattern 160.

The region where the liquid film L is formed on the upper surface of the substrate W is referred to as the liquid film forming region LR. On the upper surface of the substrate W, a region in contact with the gas phase layer VL having a sufficient thickness is referred to as a gas phase layer forming region VR.
When the vapor phase layer VL having a sufficient thickness is formed, the frictional resistance acting on the liquid film L on the substrate W is so small that it can be regarded as zero. As shown in FIG. 9A, the gas phase layer forming region VR is a substantially circular region that covers the central portion of the upper surface of the substrate W. The gas phase layer forming region VR substantially coincides with the irradiation region RR. The liquid film forming region LR includes a gas phase layer forming region VR and a region on the upper surface of the substrate W outside the gas phase layer forming region VR.

When the irradiation region RR is located at the center of the upper surface of the substrate W, the non-irradiation region NR outside the irradiation region RR on the upper surface of the substrate W has not reached the heating temperature. Therefore, the gas phase layer VL is not formed at all, or the amount of the gas phase layer VL formed is insufficient, and the thickness of the gas phase layer VL cannot be maintained to a sufficient thickness. Therefore, the gas phase layer forming region VR is not formed in the non-irradiated region NR on the upper surface of the substrate W.

After the gas phase layer forming region VR is formed, the liquid film removing step of removing the liquid film L from the upper surface of the substrate W is executed while maintaining the state in which the gas phase layer forming region VR is formed (step S7). ..
Specifically, even after the gas phase layer forming region VR is formed, the irradiation region RR is maintained at the center of the upper surface of the substrate W by arranging the lamp unit 12 at the light irradiation position. Therefore, even after the gas phase layer forming region VR is formed, the heating of the central portion of the upper surface of the substrate W by the lamp unit 12 is maintained. Maintaining heating for the central portion of the upper surface of the substrate W promotes evaporation of the treatment liquid held in the vapor phase layer VL at the central portion of the upper surface of the substrate W.

Further, by maintaining the heating of the central portion of the upper surface of the substrate W, a large temperature difference is generated between the irradiation region RR and the non-irradiation region NR on the upper surface of the substrate W. Due to this temperature difference, heat convection flowing from the central portion to the peripheral portion is formed on the upper surface of the substrate W. Since the substrate W is rotating, a centrifugal force acts on the liquid film L.
Since the rotation speed of the substrate W is the paddle speed, the centrifugal force applied to the liquid film L is relatively weak. Further, the heat convection generated on the upper surface of the substrate W is also relatively weak. However, as described above, the frictional resistance acting on the liquid film L in the gas phase layer forming region VR is so small that it can be regarded as zero. Therefore, these centrifugal forces and heat convection push the low surface tension liquid outward. As a result, the thickness of the central portion of the liquid film L is reduced, and as shown in FIG. 8D, a substantially circular opening 100 is formed in the central portion of the liquid film L. The opening 100 is an exposed hole that exposes the upper surface of the substrate W.

As the liquid film L is partially removed by the formation of the opening 100, the gas phase layer forming region VR exhibits an annular shape as shown in FIG. 9B. The irradiation area RR has a circular shape. By forming the opening 100, as shown in the enlarged view of FIG. 8D, between the liquid film L of the gas phase layer forming region VR and the opening 100, that is, the inner peripheral edge of the liquid film L of the gas phase layer forming region VR. A gas-liquid interface GL is formed in.

In this way, due to the evaporation of the treatment liquid, the generation of thermal convection, and the action of centrifugal force, as shown in FIG. 8D, the low surface tension liquid held by the vapor phase layer VL is eliminated, and the center of the liquid film L is removed. An opening 100 is rapidly formed in the portion (opening forming step). By forming the opening 100, the liquid film L is made circular. By forming the opening 100, the liquid film forming region LR is also made annular as shown in FIG. 9B.

Even after the vapor phase layer VL is formed, the heating of the substrate W by the heater unit 6 is continued, and the entire liquid film L is kept warm (liquid film heat retaining step). Therefore, it is possible to suppress the disappearance of the gas phase layer VL when the opening 100 is formed.
Even after the opening 100 is formed in the liquid film L, the substrate W is heated by the heater unit 6 and the lamp unit 12. Since the low surface tension liquid does not exist in the region where the opening 100 is formed (opening formation region OR) on the upper surface of the substrate W, the temperature of the substrate W is rapidly raised by the heater unit 6 and the lamp unit 12. As a result, a temperature difference occurs between the inside of the inner peripheral edge of the liquid film L (opening formation region OR) and the outside of the inner peripheral edge of the liquid film L (liquid film forming region LR). Specifically, the temperature of the substrate W is high in the opening forming region OR, and the temperature of the substrate W is low in the liquid film forming region LR. Due to this temperature difference, the generation of heat convection continues near the inner peripheral edge of the liquid film L. Further, since the substrate W is rotating, a centrifugal force acts on the liquid film L. Therefore, as shown in FIGS. 8D and 8E, the opening 100 is enlarged by the action of centrifugal force and the generation of heat convection (opening expansion step).

After the opening 100 is formed, the third moving unit 35 changes the height position of the lamp unit 12 to a closer position closer to the upper surface of the substrate W than the separation position (as shown by the alternate long and short dash line in FIG. 8D). Irradiation unit proximity process). As a result, the temperature of the opening forming region OR on the upper surface of the substrate W can be rapidly raised. When the lamp unit 12 is located in a close position, the distance between the lower surface of the lamp unit 12 and the upper surface of the substrate W is, for example, 4 mm.

When the expansion of the opening 100 is started, the third moving unit 35 attaches the low surface tension liquid nozzle 10, the gas nozzle 11 and the lamp unit 12 to the substrate W while maintaining the height position of the lamp unit 12 at a close position. Move toward the peripheral edge (proximity movement process). At that time, the low surface tension liquid nozzle 10, the gas nozzle 11 and the lamp so that the gas nozzle 11 is located inside the substrate W with respect to the lamp unit 12, that is, the gas nozzle 11 faces the opening formation region OR. Unit 12 is moved. As the lamp unit 12 moves toward the peripheral edge of the upper surface of the substrate W, the irradiation region RR moves toward the peripheral edge of the upper surface of the substrate W.

The substrate W is rotating even while the opening 100 is being expanded. Therefore, the irradiation region RR moves relative to the upstream side in the rotation direction of the substrate W. As a result, the inner peripheral edge of the liquid film L is heated all around, and the inner peripheral edge of the liquid film L forms a vapor phase layer VL having a sufficient thickness all around. That is, as shown in FIG. 9C, the gas phase layer forming region VR becomes an annular shape while the opening 100 is being expanded. During the expansion of the opening 100, the gas phase layer VL is also formed in the non-irradiated region NR.

In this way, in the opening expansion step, the irradiation region RR is moved toward the peripheral edge of the upper surface of the substrate W while rotating the substrate W. Therefore, the opening 100 is expanded while maintaining the state in which the vapor phase layer VL is formed on the inner peripheral edge of the liquid film L.
As shown in FIG. 9C, the irradiation region RR is moved following the expansion of the opening 100 so as to be arranged across the liquid film forming region LR and the opening forming region OR. Therefore, the inner peripheral edge of the liquid film L can be heated with a sufficient amount of heat. Therefore, a situation may occur in which the gas phase layer VL is not formed on the inner peripheral edge of the liquid film L due to insufficient heat, or a situation in which the once formed gas phase layer VL disappears and the low surface tension liquid comes into contact with the upper surface of the substrate W. Can be suppressed. That is, the gas phase layer VL can be stably formed on the inner peripheral edge of the liquid film L.

Although the opening 100 can be expanded to some extent by the movement of the low surface tension liquid by heat convection, it is low when the outer peripheral edge of the opening 100 reaches the peripheral edge of the upper surface of the substrate W as shown in FIGS. 8F and 9D. Surface tension The movement of the liquid may stop.
More specifically, in a state where the outer peripheral edge of the opening 100 reaches the peripheral edge of the upper surface of the substrate W, the total amount of the processing liquid on the substrate W is small, so that the substrate W inside the opening 100 and outside the opening 100 The temperature difference between the two becomes smaller. Therefore, the low surface tension liquid is in an equilibrium state in which the substrate W repeatedly moves inward and outward. In this case, when the low surface tension liquid returns to the inside of the substrate W, the low surface tension liquid may come into direct contact with the upper surface of the substrate W in which the vapor phase layer VL has been lost. Therefore, there is a possibility that the pattern collapses due to the surface tension of the low surface tension liquid and particles due to poor drying may occur.

When the opening 100 is enlarged, the substrate W is rotating. Therefore, this equilibrium state can be eliminated if the centrifugal force acting on the liquid film L is sufficiently large. However, if the centrifugal force is not large enough, the equilibrium state will not be resolved. In particular, at a low rotation speed of about 10 rpm, the equilibrium state may not be resolved.
Therefore, when the inner peripheral edge of the liquid film L reaches the peripheral edge of the upper surface of the substrate W, the gas valve 53A is opened. As a result, as shown in FIG. 8F, the gas is blown toward the opening formation region OR. The gas that collides with the upper surface of the substrate W flows along the upper surface of the substrate W and pushes the low surface tension liquid to the outside of the substrate W to promote the expansion of the opening 100 (expansion promotion step). As a result, the low surface tension liquid is removed from the upper surface of the substrate W without stopping. It is possible to suppress or prevent pattern collapse and particle generation.

By expanding the opening 100, the liquid film L is finally completely removed from the upper surface of the substrate W. After that, the supply of electric power from the lamp energizing unit 90 to the lamp unit 12 is stopped, and the gas valve 53A is closed. Then, the third moving unit 35 moves the low surface tension liquid nozzle 10, the gas nozzle 11, and the lamp unit 12 to the retracted position.
Then, the spin motor 23 stops the rotation of the substrate W. The guard elevating unit 74 moves the first guard 71A and the second guard 71B to the lower position. Then, the heater elevating unit 65 moves the heater unit 6 to the lower position.

The transfer robot CR enters the processing unit 2, scoops the processed substrate W from the chuck pin 20 of the spin chuck 5, and carries it out of the processing unit 2 (step S8). The substrate W is passed from the transfer robot CR to the transfer robot IR, and is housed in the carrier C by the transfer robot IR.
According to the first embodiment, the irradiation region RR set in the central portion of the upper surface of the substrate W is irradiated with light to heat the central portion of the upper surface of the substrate W. As a result, the low surface tension liquid in contact with the central portion of the upper surface of the substrate W evaporates, and the vapor phase layer VL is formed in the central portion of the upper surface of the substrate W. By forming the gas phase layer VL, the liquid film L floats from the central portion of the upper surface of the substrate W. An opening 100 is formed in the central portion of the liquid film L by eliminating the low surface tension liquid held by the vapor phase layer VL formed in the central portion of the upper surface of the substrate W.

After the opening 100 is formed, the irradiation region RR is moved toward the peripheral edge of the upper surface of the substrate W while rotating the substrate W, so that the gas phase layer VL is formed on the inner peripheral edge of the liquid film L. The opening 100 is expanded while maintaining. In other words, when the liquid film L is removed from the upper surface of the substrate W, the annular region (gas phase layer forming region VR) in which the gas phase layer VL is formed becomes the peripheral edge of the upper surface of the substrate W as the opening 100 expands. Move towards the department. The gas phase layer forming region VR moves on the substrate W so that the inner peripheral edge and the outer peripheral edge become large.

As a method of forming and expanding an opening in the liquid film L to remove the liquid film L from the upper surface of the substrate, unlike the present embodiment, the liquid film L is placed on the substrate with the heater unit 6 in contact with the lower surface of the substrate W. A method of removing the liquid film L from the substrate W, or a method of removing the liquid film L from the substrate W while heating the entire upper surface of the substrate W by a lamp unit (a lamp unit different from the first embodiment) facing the entire upper surface of the substrate W. Can be assumed. When these methods are adopted, at the place where the liquid film L is finally removed on the upper surface of the substrate W, the gas phase layer VL is formed for a long period from the start to the end of the removal of the liquid film L. It needs to be maintained.

On the other hand, in the first embodiment, the annular gas phase layer forming region VR is expanded together with the opening 100. Therefore, as compared with the method in which the liquid film L held in the gas phase layer VL is eliminated after the gas phase layer VL is formed over the entire upper surface of the substrate W, the gas phase is formed after the gas phase layer VL is formed. The time until the low surface tension liquid held in the layer VL is removed can be shortened at an arbitrary position on the upper surface of the substrate W. Thereby, it is possible to prevent the entire substrate W from being excessively (long-term) heated when the opening 100 is formed and expanded. Therefore, it is possible to prevent the low surface tension liquid from locally evaporating and splitting the liquid film L.

The longer the heating time for maintaining the gas phase layer VL, the higher the possibility that the gas phase layer VL disappears due to the local decrease in the temperature of the liquid film L or the substrate W. The time from the formation of the phase layer VL to the removal of the low surface tension liquid held in the gas phase layer VL is shortened at an arbitrary position on the upper surface of the substrate W. Therefore, pattern collapse due to heating for maintaining the gas phase layer VL for a long period of time can be suppressed.

Further, the opening 100 is formed and expanded while the low surface tension liquid is kept warm by the heater unit 6. Therefore, the gas phase layer VL can be quickly formed in the irradiation region RR. Further, it is possible to suppress a temperature drop of the substrate W in the non-irradiation region NR (particularly, the region opposite to the irradiation region RR with respect to the rotation center position on the upper surface of the substrate W). Therefore, it is possible to prevent the formed gas phase layer VL from moving to the outside of the irradiation region RR (downstream in the rotation direction from the irradiation region RR) and disappearing.

As described above, the low surface tension liquid can be satisfactorily removed from the upper surface of the substrate W. As a result, it is possible to suppress pattern collapse due to the surface tension of the low surface tension liquid and particle generation due to poor drying.
Further, according to the first embodiment, in the liquid film heat retaining step, the substrate W is heated by the heater unit 6 arranged at a position (second heating position) away from the lower surface of the substrate W. Therefore, regardless of the configuration of the heater unit 6, that is, even if the heater unit 6 cannot rotate together with the substrate, the substrate W can be easily rotated when the opening 100 is expanded. Further, as compared with the configuration in which the heater unit 6 is brought into contact with the substrate W, the entire substrate W can be appropriately heated. Further, it is possible to prevent the dirt adhering to the heater unit 6 from being transferred to the substrate W. Further, unlike the configuration in which the heater unit 6 is brought into contact with the substrate W, it is not necessary to accurately adjust the parallelism between the facing surface 6a and the lower surface of the substrate W, so that the substrate processing device 1 can be avoided from being complicated.

Further, by blowing gas onto the opening forming region OR on the upper surface of the substrate W while the opening 100 is being expanded, the opening forming region OR may be cooled. When the opening forming region OR is cooled, the temperature difference between the liquid film forming region LR and the opening forming region OR on the upper surface of the substrate W becomes insufficient, and there is a possibility that heat convection is not sufficiently formed in the liquid film L. be. This may hinder the expansion of the opening 100. Therefore, in the first embodiment, in the opening expansion step, the gas is not sprayed onto the upper surface of the substrate W until the inner peripheral edge of the liquid film L reaches the peripheral edge of the upper surface of the substrate W. Therefore, it is possible to avoid cooling the opening forming region OR on the upper surface of the substrate W by spraying gas.

<Second Embodiment>
FIG. 10 is a vertical cross-sectional view of the lamp unit 12 provided in the substrate processing apparatus 1P according to the second embodiment. FIG. 11 is a bottom view of the lamp unit 12 provided in the substrate processing apparatus 1P. In FIGS. 10 and 11, the same reference numerals as those in FIG. 1 and the like are added to the same configurations as those shown in FIGS. 1 to 9D, and the description thereof will be omitted. Similarly, in FIGS. 12A to 12D, which will be described later, the same reference numerals as those in FIGS. 1 and the like will be added and the description thereof will be omitted.

The main difference between the substrate processing apparatus 1P according to the second embodiment and the substrate processing apparatus 1 according to the first embodiment (see FIG. 3) is that, as shown in FIG. 10, the gas nozzle 11 is the lamp unit 12. The point is that the inside of the lamp housing 81 is inserted in the vertical direction.
In the lamp unit 12 of the second embodiment, as shown in FIG. 11, a plurality of (for example, 52) light sources 84 are provided, and the plurality of light sources 84 are arranged in a triple ring. The individual light sources 84 are, for example, LEDs (light emitting diodes). The plurality of light sources 84 are dispersedly arranged over the entire lower surface of the lamp substrate 83. The arrangement density of the light source 84 on the lamp substrate 83 is substantially uniform. The plurality of light sources 84 constitute an annular light emitting portion 12a having a spread in the horizontal direction. The light emitting unit 12a surrounds the discharge port 11a in an annular shape when viewed from below.

The low surface tension liquid nozzle 10 is attached to the outer wall surface 81a of the lamp housing 81 of the lamp unit 12 and is arranged outside the lamp unit 12, as in the first embodiment.
The substrate processing apparatus 1P according to the second embodiment can be used to perform the same substrate processing (see FIG. 7) as the substrate processing apparatus 1 according to the first embodiment. However, the substrate treatment according to the second embodiment is different from the substrate treatment according to the first embodiment in the liquid film removal step (step S7). Specifically, in the substrate treatment according to the second embodiment, in the opening forming step, an opening forming promoting step for promoting the formation of the opening 100 is executed by blowing a gas to the central portion of the liquid film L. Hereinafter, the liquid film removing step of the substrate treatment according to the second embodiment will be described in more detail.

12A to 12D are schematic views for explaining a state of substrate processing by the substrate processing apparatus 1P.
In the substrate treatment according to the second embodiment, the liquid film removal step (step S7) is executed after the gas phase layer forming step (step S6) as in the substrate treatment according to the first embodiment. As shown in FIG. 12A, in the gas phase layer forming step, the third moving unit 35 moves the lamp unit 12 in the horizontal direction and arranges the lamp unit 12 at the light irradiation position. The light irradiation position is, for example, the central position. When the lamp unit 12 is arranged at the light irradiation position, the discharge port 11a of the gas nozzle 11 faces the rotation center position on the upper surface of the substrate W.

By arranging the lamp unit 12 at the light irradiation position even after the gas phase layer forming region VR is formed, the irradiation region RR is maintained in the central portion of the upper surface of the substrate W. Therefore, even after the gas phase layer forming region VR is formed, the heating of the central portion of the upper surface of the substrate W by the lamp unit 12 is maintained. Maintaining heating for the central portion of the upper surface of the substrate W promotes evaporation of the treatment liquid held in the vapor phase layer VL at the central portion of the upper surface of the substrate W.

Further, by maintaining the heating of the central portion of the upper surface of the substrate W, a large temperature difference is generated between the irradiation region RR and the non-irradiation region NR on the upper surface of the substrate W. Due to this temperature difference, heat convection flowing from the central portion to the peripheral portion is formed on the upper surface of the substrate W. Since the substrate W is rotating, a centrifugal force acts on the liquid film L.
Since the rotation speed of the substrate W is the paddle speed, the centrifugal force applied to the liquid film L is relatively weak. Further, the heat convection generated on the upper surface of the substrate W is also relatively weak. However, as described above, the frictional resistance acting on the liquid film L in the gas phase layer forming region VR is so small that it can be regarded as zero. Therefore, these centrifugal forces and heat convection push the low surface tension liquid outward. As a result, the thickness of the central portion of the liquid film L is reduced, and as shown in FIG. 12B, a substantially circular opening 100 is formed in the central portion of the liquid film L. The opening 100 is an exposed hole that exposes the upper surface of the substrate W.

The gas valve 53A is opened at the same time as the irradiation of the light from the lamp unit 12 is started, or before the opening 100 is formed after the irradiation of the light from the lamp unit 12 is started. Therefore, the gas is sprayed toward the central portion of the liquid film L. By spraying the gas, the low surface tension liquid in the central portion of the upper surface of the substrate W is pushed away toward the peripheral edge portion of the substrate W. In the state where the gas phase layer forming region VR is formed, the frictional resistance acting on the liquid film L on the substrate W is so small that it can be regarded as zero. Therefore, the low surface tension liquid in the central portion of the substrate W can be quickly repelled by spraying the gas. Thereby, the formation of the opening 100 can be promoted (opening formation promoting step).

As shown in FIG. 9B, the gas phase layer forming region VR exhibits an annular shape due to the partial removal of the liquid film L by the formation of the opening 100. By forming the opening 100, as shown in the enlarged view of FIG. 12B, between the liquid film L of the gas phase layer forming region VR and the opening 100, that is, the inner peripheral edge of the liquid film L of the gas phase layer forming region VR. A gas-liquid interface GL is formed in.
In this way, as shown in FIG. 12B, an opening 100 is rapidly formed in the central portion of the liquid film L of the treatment liquid due to the evaporation of the treatment liquid, the generation of heat convection, and the action of centrifugal force (opening forming step). ). By forming the opening 100, the liquid film L is made circular. As the opening 100 is formed, the liquid film forming region LR also becomes annular as shown in FIG. 9B. After the opening 100 is formed, the gas valve 53A is closed once. As a result, the discharge of gas from the gas nozzle 11 is stopped.

Even after the vapor phase layer VL is formed, the heating of the substrate W by the heater unit 6 is continued, and the entire liquid film L is kept warm (liquid film heat retaining step). Therefore, it is possible to suppress the disappearance of the gas phase layer VL when the opening 100 is formed.
Even after the opening 100 is formed in the liquid film L, the substrate W is heated by the heater unit 6 and the lamp unit 12. Since the low surface tension liquid does not exist in the region where the opening 100 is formed (opening formation region OR) on the upper surface of the substrate W, the temperature of the substrate W is rapidly raised by the heater unit 6 and the lamp unit 12. As a result, a temperature difference occurs between the inside of the inner peripheral edge of the liquid film L (opening formation region OR) and the outside of the inner peripheral edge of the liquid film L (liquid film forming region LR).

Specifically, the temperature of the substrate W is high in the opening forming region OR, and the temperature of the substrate W is low in the liquid film forming region LR. Due to this temperature difference, the generation of heat convection continues near the inner peripheral edge of the liquid film L. Further, since the substrate W is rotating, a centrifugal force acts on the liquid film L. Therefore, as shown in FIGS. 12B and 12C, the opening 100 is enlarged by the action of centrifugal force and the generation of heat convection (opening expansion step).

After the opening 100 is formed, the third moving unit 35 changes the height position of the lamp unit 12 to a closer position closer to the upper surface of the substrate W than the separation position (as shown by the alternate long and short dash line in FIG. 12B). Irradiation unit proximity process). As a result, the temperature of the opening forming region OR on the upper surface of the substrate W can be rapidly raised.
When the expansion of the opening 100 is started, the third moving unit 35 attaches the low surface tension liquid nozzle 10, the gas nozzle 11 and the lamp unit 12 to the substrate W while maintaining the height position of the lamp unit 12 at a close position. Move toward the peripheral edge (proximity movement process). At that time, the low surface tension liquid nozzle 10, the gas nozzle 11 and the lamp unit 12 are moved so that the gas nozzle 11 is located inside the substrate W with respect to the lamp unit 12. As the lamp unit 12 moves toward the peripheral edge of the upper surface of the substrate W, the irradiation region RR moves toward the peripheral edge of the upper surface of the substrate W.

The substrate W is rotating even while the opening 100 is being expanded. Therefore, the irradiation region RR moves relative to the upstream side in the rotation direction of the substrate W. As a result, the inner peripheral edge of the liquid film L is heated all around, and the inner peripheral edge of the liquid film L forms a vapor phase layer VL having a sufficient thickness all around. That is, as shown in FIG. 9C, the gas phase layer forming region VR becomes an annular shape while the opening 100 is being expanded. During the expansion of the opening 100, the gas phase layer VL is also formed in the non-irradiated region NR.

In the opening expansion step, as shown in FIG. 9C, the lamp unit 12 is moved so that the irradiation region RR is arranged so as to straddle the liquid film forming region LR and the opening forming region OR. Therefore, the opening 100 is expanded while maintaining the state in which the vapor phase layer VL is formed on the inner peripheral edge of the liquid film L.
As shown in FIG. 9C, the irradiation region RR is moved following the expansion of the opening 100 so as to be arranged across the liquid film forming region LR and the opening forming region OR. Therefore, the inner peripheral edge of the liquid film L can be heated with a sufficient amount of heat. Therefore, a situation may occur in which the gas phase layer VL is not formed on the inner peripheral edge of the liquid film L due to insufficient heat, or a situation in which the once formed gas phase layer VL disappears and the low surface tension liquid comes into contact with the upper surface of the substrate W. Can be suppressed. That is, the gas phase layer VL can be stably formed on the inner peripheral edge of the liquid film L.

As described in the first embodiment, the movement of the low surface tension liquid due to the centrifugal force due to the low rotation speed and the generation of thermal convection can expand the opening 100 to some extent, but FIGS. 12D and 9D. When the outer peripheral edge of the opening 100 reaches the peripheral edge of the upper surface of the substrate W as shown in the above, the movement of the low surface tension liquid may stop. Therefore, also in the second embodiment, the gas valve 53A is opened when the inner peripheral edge of the liquid film L reaches the peripheral edge portion of the upper surface of the substrate W. As a result, the gas is sprayed on the upper surface of the substrate W toward the inside (opening formation region OR) of the inner peripheral edge of the liquid film L. The gas that collides with the upper surface of the substrate W flows along the upper surface of the substrate W and pushes the low surface tension liquid to the outside of the substrate W to expand the opening 100. As a result, the low surface tension liquid is removed from the upper surface of the substrate W without stopping. It is possible to suppress or prevent pattern collapse and particle generation.

However, the discharge port 11a of the gas nozzle 11 according to the second embodiment is located at the center of the light emitting unit 12a. Therefore, the gas discharged from the discharge port 11a of the gas nozzle 11 is sprayed to the center of the irradiation region RR. That is, the gas is sprayed at a position near the inner peripheral edge of the liquid film L in the opening formation region OR. As a result, a larger spraying force can be applied to the liquid film L as compared with the configuration in which the discharge port 11a of the gas nozzle 11 is located outside the light emitting portion 12a (the configuration of the first embodiment).

According to the second embodiment, the low surface tension liquid can be satisfactorily removed from the upper surface of the substrate W as in the first embodiment. As a result, it is possible to suppress pattern collapse due to the surface tension of the low surface tension liquid and particle generation due to poor drying.
<Third Embodiment>
FIG. 13 is a schematic partial cross-sectional view showing a schematic configuration of a processing unit 2 provided in the substrate processing apparatus 1Q according to the third embodiment. In FIG. 13, the same reference numerals as those in FIGS. 1 and the like are added to the same configurations as those shown in FIGS. 1 to 12D, and the description thereof will be omitted.

As shown in FIG. 13, the substrate processing apparatus 1Q according to the third embodiment is mainly different from the substrate processing apparatus 1 according to the first embodiment (see FIG. 3) in that the processing unit 2 is the heater unit 6. Instead, it includes a heating fluid nozzle 13 that supplies a heating fluid to the lower surface of the substrate W.
The heating fluid nozzle 13 is inserted into a through hole 21a that opens at the center of the upper surface of the spin base 21 and a hollow rotating shaft 22. The discharge port 13a of the heating fluid nozzle 13 is exposed from the upper surface of the spin base 21. The discharge port 13a of the heating fluid nozzle 13 faces the central portion of the lower surface of the substrate W from below. The central portion of the lower surface of the substrate W is a region including a rotation center position of the lower surface of the substrate W and a position around the rotation center position on the lower surface of the substrate W.

The heating fluid nozzle 13 is connected to a heating fluid pipe 44 that guides the heating fluid to the heating fluid nozzle 13. When the heating fluid valve 54 interposed in the heating fluid pipe 44 is opened, the heating fluid is discharged in a continuous flow upward from the discharge port 13a of the heating fluid nozzle 13.
The heating fluid is, for example, hot water. The heating fluid is a fluid whose temperature is higher than normal temperature and lower than the boiling point of the low surface tension liquid. The heating fluid is not limited to hot water, and may be a gas such as high-temperature nitrogen gas, and may be any fluid that can heat the substrate W.

Using the substrate processing apparatus 1Q according to the third embodiment, the same substrate processing as the substrate processing apparatus 1 according to the first embodiment (see FIG. 7) can be executed.
However, as shown in FIG. 14A, in the substrate treatment according to the third embodiment, after the liquid film L of the low surface tension liquid is formed on the upper surface of the substrate W, the irradiation of light on the upper surface of the substrate W is started. The heated fluid valve 54 is opened before it is closed.

When the heating fluid valve 54 is opened, the heating fluid is discharged from the heating fluid nozzle 13 toward the central portion of the lower surface of the substrate W. Centrifugal force due to the rotation of the substrate W acts on the heating fluid supplied to the central portion of the lower surface of the substrate W. Therefore, the heating fluid spreads over the entire lower surface of the substrate W by centrifugal force, and the entire substrate W is heated by the heating fluid (fluid heating step). The heating fluid nozzle 13 is an example of a substrate heating unit.

The heating fluid has a temperature higher than room temperature (eg, 25 ° C.) and lower than the boiling point of the low surface tension liquid. Therefore, the liquid film L is kept at a temperature higher than room temperature (for example, 25 ° C.) and lower than the boiling point of the low surface tension liquid (liquid film heat retaining step). When the low surface tension liquid is IPA, the heating fluid is, for example, water at 60 ° C. If so, the liquid film L can be kept warm at a temperature higher than room temperature and lower than the boiling point of IPA (82.6 ° C.).

In the third embodiment, the entire substrate W can be heated only by supplying the heating fluid to the central portion of the lower surface of the substrate W.
The supply of the heating fluid to the lower surface of the substrate W is continued even when the opening 100 is formed in the liquid film L (opening forming step) as shown in FIG. 14B, and the opening 100 is formed as shown in FIGS. 14C and 14D. It is also continued when expanding (opening expansion process).

According to the third embodiment, the low surface tension liquid can be satisfactorily removed from the upper surface of the substrate W as in the first embodiment. As a result, it is possible to suppress pattern collapse due to the surface tension of the low surface tension liquid and particle generation due to poor drying.
<Other Embodiments>
The present invention is not limited to the embodiments described above, and can be implemented in still other embodiments.

For example, in the substrate processing apparatus 1P according to the second embodiment, the heating fluid nozzle 13 according to the third embodiment can be provided instead of the heater unit 6.
Further, the low surface tension liquid nozzle 10 may be arranged between the lamp unit 12 and the gas nozzle 11. Specifically, the low surface tension liquid nozzle 10 is attached to the outer wall surface 81a of the lamp housing 81 of the lamp unit 12, and the gas nozzle 11 is attached to the low surface tension liquid nozzle 10 at a position opposite to the lamp unit 12. It may have been. Further, the lamp unit 12, the low surface tension liquid nozzle 10, and the gas nozzle 11 may be configured to be movable independently.

After the liquid film removal step is completed, a spin-drying step of shaking off the liquid from the upper surface of the substrate W may be executed. Specifically, after the liquid film L is removed from the upper surface of the substrate W, the spin motor 23 accelerates the rotation of the substrate W to rotate the substrate W at a high speed at a predetermined drying speed. The drying rate is, for example, 1500 rpm. The spin-drying step is performed for a predetermined time, for example 30 seconds. As a result, even if a small amount of the low surface tension liquid remains on the substrate W, a large centrifugal force acts on the low surface tension liquid, and the low surface tension liquid is shaken off around the substrate W.

In addition, various changes can be made within the scope of the claims.

1: Substrate processing device 1P: Substrate processing device 1Q: Substrate processing device 3: Controller 6: Heater unit 12: Lamp unit (irradiation unit)
13: Heating fluid nozzle (board heating unit)
20: Chuck pin (board holding unit)
21: Spin base (board holding unit)
23: Spin motor (board rotation unit)
35: Third moving unit (moving unit)
100: Aperture A1: Rotation axis HR: Heating region L: Liquid film LR: Liquid film formation region OR: Aperture formation region VL: Gas phase layer W: Substrate

Claims (10)

A liquid film forming step of supplying a treatment liquid to the upper surface of a horizontally held substrate to form a liquid film of the treatment liquid on the upper surface of the substrate.
A liquid film heat insulating step of keeping the liquid film warm by heating the entire substrate to a temperature lower than the boiling point of the treatment liquid.
While executing the liquid film heat retention step, the irradiation unit facing the upper surface of the substrate irradiates the irradiation region set in the central portion of the upper surface of the substrate with light to heat the central portion of the upper surface of the substrate. A gas phase layer forming step of evaporating the treatment liquid in contact with the central portion of the upper surface of the substrate to form a vapor phase layer in contact with the upper surface of the substrate and holding the treatment liquid in the central portion of the liquid film.
An opening forming step of forming an opening in the central portion of the liquid film by removing the treatment liquid held by the gas phase layer.
A substrate rotation step of rotating the substrate around a rotation axis extending vertically through the central portion of the upper surface of the substrate.
By moving the irradiation region toward the peripheral edge of the substrate while executing the liquid film heat retention step and the substrate rotation step, the state in which the vapor phase layer is formed on the inner peripheral edge of the liquid film is maintained. A substrate processing method including an opening enlargement step of expanding the opening. In the opening expansion step, the irradiation region is arranged so as to straddle the liquid film forming region in which the liquid film is formed on the upper surface of the substrate and the opening forming region in which the opening is formed on the upper surface of the substrate. The substrate processing method according to claim 1, further comprising a step of moving the irradiation region following the expansion of the opening. 1. The substrate processing method described in 1. The substrate treatment according to claim 1 or 2, wherein the liquid film heat retaining step includes a fluid heating step of supplying a heating fluid to a central portion of the lower surface of the substrate to heat the substrate to keep the liquid film warm. Method. The claim comprises the step of forming the opening in the central portion of the liquid film by maintaining the irradiation region in the central portion of the upper surface of the substrate after the vapor phase layer is formed. The substrate processing method according to any one of 1 to 4. The substrate processing method according to claim 5, further comprising an opening formation promoting step of promoting the formation of the opening by blowing a gas toward the central portion of the liquid film on which the gas phase layer is formed. When the inner peripheral edge of the liquid film reaches the peripheral edge of the upper surface of the substrate, gas is blown on the upper surface of the substrate to the inside of the inner peripheral edge of the liquid film to promote the expansion of the opening. The substrate processing method according to any one of claims 1 to 6, further comprising a step. In the opening forming step, the opening is formed with the height position of the irradiation unit set to a separated position.
An irradiation unit proximity step of changing the height position of the irradiation unit to a position closer to the upper surface of the substrate than the separation position after the opening is formed.
In the opening expansion step, by moving the irradiation unit toward the peripheral edge of the substrate while maintaining the height position of the irradiation unit at the close position, the irradiation region is moved toward the peripheral edge of the substrate. The substrate processing method according to any one of claims 1 to 7, further comprising a proximity moving step of moving. The substrate processing method according to any one of claims 1 to 7, wherein the light emitted from the irradiation unit has a wavelength that allows the light to pass through the processing liquid. A board holding unit that holds the board horizontally,
A treatment liquid supply unit that supplies the treatment liquid to the upper surface of the substrate held horizontally, and
A substrate heating unit that heats the entire horizontally held substrate to a temperature lower than the boiling point of the treatment liquid, and
An irradiation unit that is configured to face the upper surface of the substrate held horizontally and irradiates light toward the center of the upper surface of the substrate.
A moving unit that moves the irradiation unit in the horizontal direction,
A substrate rotation unit that rotates the substrate around a rotation axis extending vertically through the central portion of the upper surface of the substrate held horizontally.
The processing liquid supply unit, the substrate heating unit, the irradiation unit, the moving unit, and a controller for controlling the substrate rotating unit are included.
A liquid film forming step of forming a liquid film of the treatment liquid on the upper surface of the substrate by supplying the treatment liquid from the treatment liquid supply unit to the upper surface of the substrate held by the substrate holding unit. The liquid film heat insulating step of heating the entire substrate by the substrate heating unit to heat the liquid film and the liquid film heat insulating step are performed toward the irradiation region set on the upper surface of the substrate. By irradiating light from the irradiation unit, the treatment liquid in contact with the central portion of the upper surface of the substrate is evaporated, and the gas phase layer in contact with the upper surface of the substrate and holding the treatment liquid is formed in the center of the liquid film. A vapor phase layer forming step of forming the gas phase layer, an opening forming step of eliminating the treatment liquid held by the vapor phase layer and forming an opening in the central portion of the liquid film, and the substrate being placed in the substrate rotating unit. By moving the irradiation unit to the moving unit and moving the irradiation region toward the peripheral edge of the substrate while executing the substrate rotating step of rotating, the liquid film heat retaining step, and the substrate rotating step, the above-mentioned A substrate processing apparatus programmed to perform an opening expansion step of expanding the opening while maintaining a state in which the vapor phase layer is formed on the inner peripheral edge of the liquid film.

Images