JP7465164B2 - Substrate processing method - Google Patents

Description

The present invention relates to a substrate processing method for processing substrates such as semiconductor wafers, glass substrates for liquid crystal displays, substrates for plasma displays, substrates for FEDs (Field Emission Displays), substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks, substrates for photomasks, ceramic substrates, and substrates for solar cells.

In the manufacture of semiconductor devices using substrates such as semiconductor wafers, a substrate processing method is performed to process the substrate. Specifically, a processing liquid is supplied to the surface of the substrate to process the surface. The substrate processing method is performed, for example, by a single-wafer substrate processing apparatus. This apparatus is equipped with a spin chuck that rotates the substrate while holding it almost horizontally, and a nozzle for supplying the processing liquid to the surface of the substrate rotated by the spin chuck. A chemical liquid is supplied to the substrate held by the spin chuck, and then a rinse liquid (pure water) is supplied, replacing the chemical liquid on the substrate with the pure water. Then, a spin drying process is performed to remove the pure water from the substrate. In the spin drying process, the substrate is rotated at high speed to shake off and remove (dry) the pure water adhering to the substrate.

If the above method is simply applied to a substrate having a surface with a fine pattern (for example, a protruding pattern or a line pattern), the pure water that has entered the gaps between the patterns may not be sufficiently removed. Therefore, a method may be used in which an organic solvent such as isopropyl alcohol (IPA) at room temperature is supplied to the surface of the substrate after rinsing with pure water, and the pure water that has entered the gaps between the fine patterns is replaced with the organic solvent, and then the surface of the substrate is dried. If a simple spin-dry process is used as this drying process, the adjacent patterns may attract each other and come into contact when the organic solvent is removed, which may lead to pattern collapse. One of the causes of this is presumed to be the surface tension of the liquid present between the adjacent patterns. Since organic solvents have a smaller surface tension than pure water, it is thought that when the liquid between the patterns is an organic solvent, pattern collapse is suppressed compared to when pure water is used. However, with the recent progress in high integration of semiconductor devices, fine patterns with high aspect ratios may be provided on the surface of the substrate, and in such cases, there is a concern that the pattern may collapse even if the liquid between the patterns is an organic solvent. For these reasons, when cleaning a substrate, simply supplying an organic solvent to the surface of the substrate before spin drying may make it difficult to sufficiently prevent pattern collapse during spin drying. To solve this problem, JP 2014-112652 A discloses the following substrate processing method.

A rinse liquid is supplied to the upper surface of the substrate on which a fine pattern has been formed and which is held in a horizontal position. Next, an organic solvent is supplied to the upper surface of the substrate, forming a liquid film of the organic solvent on the upper surface. Next, the upper surface of the substrate is maintained at a temperature higher than the boiling point of the organic solvent, forming a gas phase film of the organic solvent on the upper surface of the substrate, and a liquid film of the organic solvent is positioned above the gas phase film. Next, while maintaining the above-mentioned high temperature, the organic solvent is removed from the upper surface of the substrate. This removal is performed, for example, by ejecting an inert gas toward the center of rotation of the upper surface of the rotating substrate.

According to the above method, a gas phase film of the organic solvent is formed above the fine pattern and in the gaps between the fine patterns, and a liquid film of the organic solvent is formed above the gas phase film. In this state, the surface tension in the gaps between the fine patterns is small, so that pattern collapse due to surface tension is unlikely to occur. Therefore, even when cleaning a substrate on which a fine pattern with a high aspect ratio is formed, pattern collapse can be suppressed.

JP 2014-112652 A

However, even if optimal conditions for a substrate processing method that can prevent the collapse of a pattern on the upper surface of a substrate are found, it is difficult to repeat the substrate processing method strictly under those conditions due to process variations. Therefore, when substrate processing is repeated for mass production of semiconductor devices, if deviations from the optimal conditions exceed a limit, defects such as the above-mentioned pattern collapse may occur on the upper surface of the substrate.

The object of the present invention is to provide a substrate processing method that can suppress adverse effects on the upper surface of a substrate when drying the upper surface.

A first aspect disclosed in this specification is a substrate processing method, comprising the steps of: (a) forming a first liquid film of an organic solvent on a first substrate; (b) forming a first gas film that holds the first liquid film on an upper surface of the first substrate by heating the first substrate; (c) forming a first hole in the first liquid film held by the first gas film by irradiating the first substrate with light under a first predetermined condition; (d) expanding the first hole by irradiating the first substrate with light under a second predetermined condition different from the first condition; (e) acquiring a first image by photographing the first hole expanded by the step (d); (f) storing the first image as a reference image; (g) forming a second liquid film of an organic solvent on a second substrate after the step (f); and (h) forming a second liquid film of an organic solvent on the second substrate by heating the second substrate. (i) forming a second gas film on the upper surface of the substrate, the second gas film holding the second liquid film; (j) forming a second hole in the second liquid film held by the second gas film by irradiating the second substrate with light under the first condition; (k) acquiring a second image by photographing the second hole expanded by the step (j); (l) evaluating the progress of the expansion of the second hole by comparing the first hole in the first image as the reference image with the second hole in the second image; (m) adjusting a third condition for irradiating the second substrate with light based on the progress evaluated by the step (l); and (n) further expanding the second hole by irradiating the second substrate with light under the third condition.

The second aspect disclosed in this specification is the substrate processing method of the first aspect, in which the step (b) includes a step of irradiating the first substrate with light to heat the first substrate.

A third aspect disclosed in this specification is a substrate processing method according to the first or second aspect, in which a pattern is provided on the upper surface of the second substrate.

A fourth aspect disclosed in this specification is a substrate processing method according to the first to third aspects, in which in steps (c) and (d), the light irradiated to the first substrate is irradiated from above the top surface of the first substrate, and in steps (i), (j), and (n), the light irradiated to the second substrate is irradiated from above the top surface of the second substrate.

A fifth aspect disclosed in this specification is a substrate processing method according to any one of the first to fourth aspects, in which the third condition includes a setting condition for the intensity of the light irradiated to the second substrate.

A sixth aspect disclosed in this specification is a substrate processing method according to any one of the first to fifth aspects, in which the third condition includes a setting condition for the movement speed of an irradiated region, which is a portion of the second substrate that is irradiated with light.

The seventh aspect disclosed in this specification is the substrate processing method of the sixth aspect, in which the step (l) is performed by comparison within the irradiated region.

The eighth aspect disclosed in this specification is a substrate processing method according to any one of the first to seventh aspects, in which the third condition includes a setting condition for the rotation speed of the second substrate.

A ninth aspect disclosed in the present specification is a substrate processing method according to any one of the first to eighth aspects, in which the step (l) includes a step of comparing an area of the first hole in the first image with an area of the second hole in the second image.

A tenth aspect disclosed in the present specification is a substrate processing method according to any one of the first to ninth aspects, in which the step (l) includes a step of comparing the dimensions of the first hole in the first image with the dimensions of the second hole in the second image.

An eleventh aspect disclosed in this specification is a substrate processing method according to any one of the first to tenth aspects, in which in steps (i), (j) and (n), light for the second substrate is generated by a light source, and in step (k), the second image is captured by a camera, and the substrate processing method further includes a step (o) of evaluating a deterioration state of the light source based on the image captured by the camera.

A twelfth aspect disclosed in the present specification is a substrate processing method, comprising: (a) a step of forming a first liquid film of an organic solvent on a first substrate; (b) a step of forming a first gas film that holds the first liquid film on an upper surface of the first substrate by heating the first substrate; (c) a step of forming a first hole in the first liquid film held by the first gas film by discharging an inert gas onto the upper surface of the first substrate under a first predetermined condition; (d) a step of expanding the first hole by discharging an inert gas onto the first substrate under a second predetermined condition different from the first condition; (e) a step of acquiring a first image by photographing the first hole expanded by the step (d); (f) a step of storing the first image as a reference image; (g) a step of forming a second liquid film of an organic solvent on a second substrate after the step (f); and (h) a step of forming a first liquid film of the organic solvent on the upper surface of the second substrate by heating the second substrate. The method includes the steps of: (i) forming a second gas film that holds the film; (i) forming a second hole in the second liquid film held by the second gas film by discharging an inert gas onto the upper surface of the second substrate under the first condition; (j) expanding the second hole by discharging an inert gas onto the upper surface of the second substrate under the second condition; (k) acquiring a second image by photographing the second hole expanded by the step (j); (l) evaluating the progress of the expansion of the second hole by comparing the first hole in the first image as the reference image with the second hole in the second image; (m) adjusting a third condition for discharging an inert gas onto the upper surface of the second substrate based on the progress evaluated by the step (l); and (n) further expanding the second hole by discharging an inert gas onto the upper surface of the second substrate under the third condition.

A thirteenth aspect disclosed in this specification is the substrate processing method of the twelfth aspect, in which a pattern is provided on the upper surface of the second substrate.

A fourteenth aspect disclosed in this specification is a substrate processing method according to the twelfth or thirteenth aspect, in which the third condition includes a setting condition for the flow rate of the inert gas discharged onto the upper surface of the second substrate.

A fifteenth aspect disclosed in the present specification is a substrate processing method according to any one of the twelfth to fourteenth aspects, in which the step (l) includes a step of comparing an area of the first hole in the first image with an area of the second hole in the second image.

A sixteenth aspect disclosed in the present specification is a substrate processing method according to any one of the twelfth to fifteenth aspects, in which the step (l) includes a step of comparing the dimensions of the first hole in the first image with the dimensions of the second hole in the second image.

According to the substrate processing method of the first aspect described above, the progress of the expansion of the second hole caused by irradiating the second substrate with light under the second conditions is evaluated based on the progress of the expansion of the first hole caused by irradiating the first substrate with light under the second conditions. By adjusting the third conditions for further irradiating the second substrate with light based on this progress, the rate of further expansion of the second hole can be made closer to the standard rate of expansion. This makes it possible to suppress variation in the rate of expansion of the second hole of the second liquid film on the upper surface of the second substrate. Therefore, it is possible to suppress adverse effects on the upper surface of the substrate caused by the variation.

According to the second aspect of the substrate processing method, not only the process of forming holes in the liquid film, but also the process of forming a gas film prior to that can be performed using light.

According to the substrate processing method of the third aspect described above, the variation in the rate at which the second liquid film expands the second hole on the upper surface of the second substrate can be suppressed, thereby suppressing the collapse of the pattern provided on the upper surface of the second substrate.

According to the substrate processing method of the fourth aspect described above, since light is irradiated from above onto the first and second substrates, the light source is positioned above the first and second substrates. This makes it difficult for the chemical solution discharged onto the first and second substrates to adhere to the light source and associated members. This makes it possible to avoid damage to the light source and associated members caused by the chemical solution.

According to the fifth aspect of the substrate processing method, the third condition includes a setting condition for the intensity of the light irradiated to the second substrate. This makes it possible to effectively adjust the rate at which the second hole is further expanded.

According to the substrate processing method of the sixth aspect, the third condition includes a setting condition for the movement speed of the irradiated region, which is the portion of the second substrate that is irradiated with light. This makes it possible to effectively adjust the progress speed of the further expansion of the second hole.

According to the seventh aspect of the substrate processing method, the comparison between the first hole and the second hole for evaluating the progress is performed within the irradiated area. This can increase the reliability of the evaluation.

According to the substrate processing method of the eighth aspect, the third condition includes a setting condition for the rotation speed of the second substrate. This makes it possible to effectively adjust the progress speed of further expansion of the second hole.

According to the ninth aspect of the substrate processing method, the comparison between the first hole and the second hole to evaluate the progress is performed by comparing the areas of the first hole and the second hole. This makes it possible to average out and evaluate the effects of expansion in various directions.

According to the substrate processing method of the tenth aspect, the comparison between the first hole and the second hole to evaluate the progress is performed by comparing the dimensions of the first hole and the second hole. This allows for evaluation in a simple manner.

According to the substrate processing method of the eleventh aspect, the deterioration state of the light source is evaluated based on the image captured by the camera. This makes it possible to suppress variation in the rate of expansion of the second hole caused by irradiation with light from the light source.

According to the substrate processing method of the twelfth aspect, the progress of the expansion of the second hole caused by discharging the inert gas onto the upper surface of the second substrate under the second condition is evaluated based on the progress of the expansion of the first hole caused by discharging the inert gas onto the upper surface of the first substrate under the second condition. By adjusting the third condition for further discharging the inert gas onto the upper surface of the second substrate based on this progress, the progress rate of the further expansion of the second hole can be made closer to the standard progress rate. This makes it possible to suppress the variation in the progress rate of the expansion of the second hole of the second liquid film on the upper surface of the second substrate. Therefore, it is possible to suppress the adverse effects on the upper surface of the substrate caused by the variation.

According to the substrate processing method of the thirteenth aspect described above, the variation in the rate of expansion of the second hole in the second liquid film on the upper surface of the second substrate can be suppressed, thereby suppressing the collapse of the pattern provided on the upper surface of the second substrate.

According to the substrate processing method of the above 14th aspect, the third condition includes a setting condition for the flow rate of the inert gas discharged onto the upper surface of the second substrate. This makes it possible to effectively adjust the rate at which the second hole is further expanded.

According to the substrate processing method of the fifteenth aspect, the comparison between the first hole and the second hole to evaluate the progress is performed by comparing the areas of the first hole and the second hole. This makes it possible to average out and evaluate the effects of expansion in various directions.

According to the substrate processing method of the 16th aspect, the comparison between the first hole and the second hole to evaluate the progress is performed by comparing the dimensions of the first hole and the second hole. This allows for evaluation in a simple manner.

The objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description and accompanying drawings.

1 is a schematic plan view showing a layout of a substrate processing apparatus according to a first embodiment of the present invention; 2 is an enlarged cross-sectional view of a surface of a substrate to be processed; 2 is a schematic cross-sectional view showing a configuration of a processing unit provided in the substrate processing apparatus of FIG. 1 . 4 is a vertical cross-sectional view of a lamp unit provided in the processing unit of FIG. 3. FIG. 5 is a bottom view of the lamp unit of FIG. 4. 2 is a block diagram showing an electrical configuration of a main part of the substrate processing apparatus of FIG. 1 . FIG. 2 is a flow chart for explaining an example of a substrate processing method according to the first embodiment of the present invention. 1A to 1C are schematic diagrams for explaining a substrate processing method according to a first embodiment of the present invention; 1A to 1C are schematic diagrams for explaining a substrate processing method according to a first embodiment of the present invention; 1A to 1C are schematic diagrams for explaining a substrate processing method according to a first embodiment of the present invention; 1A to 1C are schematic diagrams for explaining a substrate processing method according to a first embodiment of the present invention; 1A to 1C are schematic diagrams for explaining a substrate processing method according to a first embodiment of the present invention; 1A to 1C are schematic diagrams for explaining a substrate processing method according to a first embodiment of the present invention; 3A to 3C are schematic views for explaining regions formed on an upper surface of a substrate in the substrate processing method according to the first embodiment of the present invention. 3A to 3C are schematic views for explaining regions formed on an upper surface of a substrate in the substrate processing method according to the first embodiment of the present invention. 3A to 3C are schematic views for explaining regions formed on an upper surface of a substrate in the substrate processing method according to the first embodiment of the present invention. 3A to 3C are schematic views for explaining regions formed on an upper surface of a substrate in the substrate processing method according to the first embodiment of the present invention. FIG. 8 is a flow diagram showing a part of the process of FIG. 7 applied to a first substrate. FIG. 8 is a flow diagram showing a part of the process of FIG. 7 applied to a second substrate. FIG. 11 is a plan view illustrating a state in which holes are formed in the liquid film by a hole forming step. FIG. 13 is a plan view illustrating a process for evaluating the progress of the expansion of a hole in a liquid film. FIG. 14 is a plan view illustrating a modified example of FIG. 13 . 10 is a schematic cross-sectional view showing a configuration of a processing unit provided in a substrate processing apparatus according to a second embodiment of the present invention. FIG. FIG. 16 is a schematic diagram showing the spin base and its related configuration as viewed from above, as shown in FIG. 15 . FIG. 16 is a schematic vertical cross-sectional view of the top head shown in FIG. 15 . FIG. 18 is a schematic diagram of the top-surface head shown in FIG. 17 as viewed from below. FIG. 16 is a schematic vertical cross-sectional view of the second lamp heater shown in FIG. 15 . FIG. 19 is a schematic diagram of the second lamp heater as viewed from below. FIG. 10 is a flow chart for explaining an example of a substrate processing method according to a second embodiment of the present invention. 10A to 10C are schematic diagrams for explaining a substrate processing method according to a second embodiment of the present invention. 10A to 10C are schematic diagrams for explaining a substrate processing method according to a second embodiment of the present invention. 10A to 10C are schematic diagrams for explaining a substrate processing method according to a second embodiment of the present invention. 10A to 10C are schematic diagrams for explaining a substrate processing method according to a second embodiment of the present invention. 10A to 10C are schematic diagrams for explaining a substrate processing method according to a second embodiment of the present invention. 10A to 10C are schematic diagrams for explaining a substrate processing method according to a second embodiment of the present invention. FIG. 22C is a schematic diagram showing the substrate in the state shown in FIG. 22B as viewed from above. FIG. 22D is a schematic diagram showing the substrate in the state shown in FIG. 22C as viewed from above. FIG. 22E is a schematic diagram showing the substrate in the state shown in FIG. 22D as viewed from above. FIG. 22F is a schematic diagram showing the substrate in the state shown in FIG. 22E as viewed from above. FIG. 22 is a flow diagram showing a part of the process of FIG. 21 applied to a first substrate. FIG. 22 is a flow diagram showing a part of the process of FIG. 21 applied to a second substrate. FIG. 11 is a flow diagram showing steps applied to a first substrate in a substrate processing method according to a third embodiment of the present invention. FIG. 11 is a flow diagram showing steps applied to a second substrate in a substrate processing method according to a third embodiment of the present invention. FIG. 11 is a schematic plan view showing a configuration of a processing unit provided in a substrate processing apparatus according to a fourth embodiment of the present invention. FIG. 11 is a schematic cross-sectional view showing a configuration of a processing unit provided in a substrate processing apparatus according to a fourth embodiment of the present invention. 6 is a diagram showing an example of a liquid supply unit connected to a first nozzle head. FIG. 13 is a diagram showing an example of a liquid supply unit connected to a second nozzle head. FIG. 13A and 13B are diagrams showing an example of a liquid supply section and an air supply section connected to a third nozzle head. FIG. 11 is a flow chart showing a substrate processing method for each substrate in accordance with a fourth embodiment of the present invention. FIG. 34 is a flow diagram showing details of the drying treatment (FIG. 33) applied to the first substrate in the fourth embodiment of the present invention. FIG. 13 is a diagram showing a state in which a liquid film is formed on the upper surface of a substrate. FIG. 4 is a partial cross-sectional view showing a schematic state in which a liquid film is formed. FIG. 13 is a diagram showing a state in which a substrate is heated. FIG. 4 is a partial cross-sectional view showing a schematic state in which a gas film is formed. FIG. 13 is a diagram showing the initial formation of a dry region in the center of the top surface of a substrate. FIG. 13 is a diagram showing the gradual expansion of a dry region. FIG. 11 is a partial cross-sectional view showing a state in which holes are formed in the liquid film by a hole forming step. FIG. 34 is a flow diagram showing details of the drying process (FIG. 33) applied to the second substrate in the fourth embodiment of the present invention. FIG. 43 is a plan view illustrating a progress evaluation step in the drying process of FIG. 42. FIG. 44 is a plan view illustrating a modified example of FIG. 43. 13 is a cross-sectional view illustrating a schematic configuration of a substrate processing apparatus according to a fifth embodiment of the present invention. 46 is a plan view illustrating a light irradiation unit in the substrate processing apparatus of FIG. 45. FIG. 34 is a flow diagram showing details of the drying process (FIG. 33) applied to the first substrate in the fifth embodiment of the present invention. FIG. 34 is a flow diagram showing details of the drying process (FIG. 33) applied to the second substrate in the fifth embodiment of the present invention. FIG. 47 is a plan view showing a first modified example of FIG. 46 . FIG. 47 is a plan view showing a second modified example of FIG. 46 .

The following describes an embodiment of the present invention with reference to the drawings. Note that the same or corresponding parts in the following drawings are given the same reference numbers and their description will not be repeated.

<1. First embodiment>
<1-1. Configuration of the substrate processing apparatus>
FIG. 1 is a schematic plan view showing a layout of a substrate processing apparatus 1 according to the first embodiment. The substrate processing apparatus 1 is a single-wafer type apparatus that processes substrates W such as silicon wafers one by one. In this embodiment, the substrate W is a disk-shaped substrate. The substrate processing apparatus 1 includes a plurality of processing units 2 that process the substrates W with a fluid, a load port LP on which a carrier C that accommodates a plurality of substrates W to be processed in the processing units 2 is placed, transport robots IR and CR that transport the substrates W between the load port LP and the processing units 2, and a controller 3 that controls the substrate processing apparatus 1. The transport robot IR transports the substrates W between the carrier C and the transport robot CR. The transport robot CR transports the substrates W between the transport robot IR and the processing units 2. The plurality of processing units 2 have, for example, the same configuration. Each processing unit 2 includes a chamber 4 and a processing cup 7 arranged in the chamber 4, and performs processing on the substrate W in the processing cup 7. The chamber 4 is formed with an entrance/exit 4A for the transport robot CR to load and unload the substrate W. The chamber 4 is provided with a shutter unit 4B for opening and closing the entrance 4A.

2, a fine uneven pattern 960 is formed on the surface of the substrate W to be processed by the substrate processing apparatus 1. The uneven pattern 960 includes fine convex structures 961 formed on the surface of the substrate W and concaves (grooves) 962 formed between adjacent structures 961. The surface of the uneven pattern 960, i.e., the surfaces of the structures 961 (convex portions) and the concave portions 962, forms an uneven pattern surface 965. The pattern surface 965 is included in the surface of the substrate W. The surface 961a of the structure 961 is composed of a tip surface 961b (top) and a side surface 961c, and the surface of the concave portion 962 is composed of a bottom surface 962b (bottom). When the structure 961 is cylindrical, a concave portion is formed inside the structure 961. The structure 961 may include an insulating film or a conductive film. The structure 961 may also be a laminated film in which multiple films are laminated. The uneven pattern 960 is a fine pattern with an aspect ratio of 3 or more. The aspect ratio of the uneven pattern 960 is, for example, 10 to 50. The width L1 of the structures 961 may be about 5 nm to 45 nm, and the distance L2 between the structures 961 may be about 5 nm to several μm. The height of the structures 961 (pattern height T1) may be, for example, about 50 nm to 5 μm. The pattern height T1 is the distance between the tip surface 961b of the structure 961 and the bottom surface 962b (bottom) of the recess 962.

Figure 3 is a schematic diagram for explaining an example configuration 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, a lamp unit 12, and an imaging unit IM.

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 vertically. The spin chuck 5 includes a plurality of chuck pins 20, a spin base 21, a rotation shaft 22, and a spin motor 23 that applies a rotational force to the rotation shaft 22. The spin chuck 5 is an example of a substrate holding and rotating 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 that hold the peripheral 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 and closing unit 24. The plurality of chuck pins 20 hold (clamp) the substrate W horizontally by being closed by the pin opening and closing unit 24. The plurality of chuck pins 20 release the substrate W by being opened by the pin opening and closing unit 24. In the open state, the multiple chuck pins 20 support the substrate W from below. The spin base 21 and the multiple chuck pins 20 constitute a substrate holding unit that holds the substrate W horizontally. The substrate holding unit is also called a substrate holder. The rotation shaft 22 extends vertically along the rotation axis A1. The upper end of the rotation shaft 22 is coupled to the center of the lower surface of the spin base 21. The spin motor 23 applies a rotational force to the rotation shaft 22. The rotation shaft 22 is rotated by the spin motor 23, thereby rotating the spin base 21. As a result, the substrate W is rotated 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 disposed between the upper surface of the spin base 21 and the lower surface of the substrate W. The heater unit 6 has an opposing surface 6a that faces the lower surface of the substrate W from below. The heater unit 6 includes a plate body 61 and a heater 62. The plate body 61 is slightly smaller than the substrate W in a plan view. The upper surface of the plate body 61 constitutes the opposing surface 6a. The heater 62 may be a resistor built into the plate body 61. The opposing surface 6a is heated by passing electricity through the heater 62. The opposing surface 6a is heated to, for example, 195°C. The heater 62 is supplied with power from a heater current supply unit 64 via a power supply line 63.

The processing unit 2 includes a heater lifting unit 65 that raises and lowers the heater unit 6 relative to the spin base 21. The heater lifting unit 65 includes, for example, a ball screw mechanism (not shown) and an electric motor (not shown) that provides driving force to the ball screw mechanism. The heater lifting unit 65 is also called a heater lifter. A lifting shaft 66 that extends vertically along the rotation axis A1 is coupled to the lower surface of the heater unit 6. The lifting shaft 66 passes through a through hole 21a formed in the center of the spin base 21 and a hollow rotation shaft 22. A power supply line 63 is passed through the lifting shaft 66. The heater lifting unit 65 raises and lowers the heater unit 6 via the lifting shaft 66. The heater unit 6 can be raised and lowered by the heater lifting unit 65 to a lower position and an upper position. The heater lifting unit 65 can be positioned not only at the lower position and the upper position, but also at any position between the lower position and the upper position.

The processing cup 7 is a member that receives liquid that splashes outward from the substrate W held by the spin chuck 5 and recovers or discards the liquid. The processing cup 7 includes a plurality of guards 71 that receive liquid that splashes outward from the substrate W held by the spin chuck 5, a plurality of cups 72 that receive liquid guided downward by the plurality of guards 71, and a cylindrical outer wall member 73 that surrounds the plurality of guards 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 to surround the spin base 21. The second guard 71B is arranged 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. The first cup 72A receives the liquid guided downward by the first guard 71A. The second cup 72B is formed integrally 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 lifting unit 74 that raises and lowers the first guard 71A and the second guard 71B separately. The guard lifting unit 74 raises and lowers the first guard 71A between a lower position and an upper position. The guard lifting unit 74 raises and lowers the second guard 71B between a lower position and an upper position. When the first guard 71A and the second guard 71B are both located in the upper position, the liquid splashed 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 splashed from the substrate W is received by the second guard 71B. When the first guard 71A and the second guard 71B are both located in the lower position, the transport robot CR can transport the substrate W into the chamber 4 and transport the substrate W out of the chamber 4. The guard lifting unit 74 includes, for example, a first ball screw mechanism (not shown) coupled to the first guard 71A, a first motor (not shown) that provides a driving force to the first ball screw mechanism, a second ball screw mechanism (not shown) coupled to the second guard 71B, and a second motor (not shown) that provides a driving force to the second ball screw mechanism. The guard lifting unit 74 is an example of a guard moving unit. The guard lifting unit 74 is also called a guard lifter.

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

The chemical nozzle 8 is, for example, a movable scan nozzle. The processing unit 2 further includes a first arm 30 to which the chemical nozzle 8 is attached at its tip, and a first moving unit 31 that moves the chemical nozzle 8 by moving the first arm 30. The first moving unit 31 rotates the first arm 30 to horizontally move the chemical nozzle 8 along a trajectory that passes through the center of the upper surface of the substrate W in a planar view. The first moving unit 31 moves the chemical nozzle 8 horizontally between the central position and the retracted position. When the chemical nozzle 8 is located at the central position, the chemical 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 an area that includes the rotation center position of the upper surface of the substrate W and the positions around the rotation center position on the upper surface of the substrate W. When the chemical nozzle 8 is located at the retracted position, the chemical nozzle 8 retracts to the periphery of the spin chuck 5 in a planar view. The first moving unit 31 includes, for example, a rotating shaft (not shown) that is connected to the first arm 30 and extends vertically, and an electric motor (not shown) that rotates the rotating shaft.

The rinse liquid nozzle 9 is a nozzle that ejects a rinse liquid to wash away the chemical liquid 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 a rinse liquid valve 51 disposed in the rinse liquid pipe 41 is opened, the rinse liquid is ejected downward from the ejection port of the rinse liquid nozzle 9 in a continuous flow. The rinse liquid is, for example, pure water (deionized water: DIW). The rinse liquid may be any of carbonated water, electrolytic ionized water, hydrogen water, ozone water, hydrochloric acid water with a diluted concentration (for example, about 10 ppm to 100 ppm), and ammonia water with a diluted concentration (for example, about 10 ppm to 100 ppm).

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 rinse liquid nozzle 9 is attached at its tip, and a second moving unit 33 that moves the rinse liquid nozzle 9 by moving the second arm 32. The second moving unit 33 rotates the second arm 32 to horizontally move the rinse liquid nozzle 9 along a trajectory that passes through the center of the upper surface of the substrate W in a planar view. The second moving unit 33 moves the rinse liquid nozzle 9 horizontally between the central position and the retracted position. When the rinse liquid nozzle 9 is located at the central position, the rinse liquid nozzle 9 faces the center 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 to the periphery of the spin chuck 5 in a planar view. The second moving unit 33 includes, for example, a rotating shaft (not shown) that is connected to the second arm 32 and extends vertically, and an electric motor (not shown) that rotates the rotating shaft.

The low surface tension liquid nozzle 10 is a nozzle that ejects a low surface tension liquid having a surface tension lower than that of 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 a low surface tension liquid valve 52 interposed in the low surface tension liquid pipe 42 is opened, the low surface tension liquid is ejected downward in a continuous flow from the ejection port 10a of the low surface tension liquid nozzle 10. The low surface tension liquid is, for example, an organic solvent such as IPA. The surface tension of IPA is lower than that of water. Organic solvents other than IPA can also be used as the low surface tension liquid. 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 can also be used as the low surface tension liquid. Not only liquids consisting of a single component, but also organic solvents mixed with other components can be used as low surface tension liquids. A 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 gas to the gas nozzle 11. A gas valve 53A and a gas flow rate control valve 53B are interposed in the gas pipe 43. When the gas valve 53A is opened, gas is continuously discharged downward from the outlet 11a of the gas nozzle 11 at a flow rate corresponding to the opening degree of the gas flow rate control 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 also 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 that includes at least one of near-infrared light, visible light, and ultraviolet light, and heats the substrate W by radiation. In other words, the lamp unit 12 is a radiation heater. Power is supplied to the lamp unit 12 from the lamp power supply unit 90 via a power supply 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 at its tip, and a third moving unit 35 (moving unit) that moves the lamp unit 12 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 as the third arm 34 moves. 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 horizontally move the low surface tension liquid nozzle 10, the gas nozzle 11, and the lamp unit 12 along a trajectory that passes through the center of the upper surface of the substrate W in a plan view. The third moving unit 35 can position the low surface tension liquid nozzle 10, the gas nozzle 11, and the lamp unit 12 in a retracted position and a central position. When the low surface tension liquid nozzle 10, the gas nozzle 11, and the lamp unit 12 are in the retracted position, they are retracted to the periphery of the spin chuck 5 in a plan view. When the low surface tension liquid nozzle 10 is in the central position, the outlet 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 in the central position, the outlet 11a of the gas nozzle 11 faces the central portion of the upper surface of the substrate W. When the lamp unit 12 is in the central 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.

Figure 4 is a vertical cross-sectional view of the lamp unit 12. Figure 5 is a bottom view of the lamp unit 12. The lamp unit 12 includes a lamp 80, a lamp housing 81 that houses 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 light sources 84 (59 in the example of FIG. 5) mounted on the underside of the lamp substrate 83. Each light source 84 is, for example, an LED (light-emitting diode). The plurality of light sources 84 are lit by the power supplied from the lamp power supply unit 90. As shown in FIG. 5, the plurality of light sources 84 are distributed and arranged over the entire underside of the lamp substrate 83. In the example of FIG. 5, one light source 84 is arranged at the center of the underside of the lamp substrate 83, and the remaining 58 light sources 84 are arranged in a quadruple annular shape surrounding the center of the underside of the lamp substrate 83. The arrangement density of the light sources 84 on the lamp substrate 83 is approximately uniform. The plurality of light sources 84 constitute a circular light-emitting section 12a that spreads in the horizontal direction. The light emitted from each light source 84 includes at least one of near-infrared light, visible light, and ultraviolet light. The wavelength of the light emitted from each light source 84 is 200 nm or more and 1100 nm or less. The light emitted from each light source 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 main body 85 and a disk-shaped bottom wall 86. The housing main body 85 is formed of a chemically resistant material such as PTFE (polytetrafluoroethylene). The bottom wall 86 is formed 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 forms 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 (e.g., aluminum, iron, copper, etc.) having high heat transfer properties. 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 body 87, a refrigerant return pipe 88c that returns the refrigerant supplied to the heat sink body 87 to the refrigerant supply source 88a, and a pump 88d that pumps out the refrigerant in the refrigerant supply pipe 88b. The cooling unit 88 supplies a refrigerant such as cooling water to the heat sink body 87. That is, the heat sink 82 is a water-cooled heat sink. As the multiple light sources 84 emit light, the lamp 80 and its surroundings are heated. 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 excessively increasing in temperature. A cooling gas may be used as a refrigerant in the heat sink 82.

The lamp unit 12 is used in a state where a liquid film L of low surface tension liquid is formed on the upper surface of the substrate W, covering the upper surface of the substrate W. The low surface tension liquid nozzle 10 and the gas nozzle 11 are attached in a vertical orientation to the outer wall surface 81a of the lamp housing 81.

As shown in FIG. 4, when the lamp 80 emits light, that is, when the multiple light sources 84 emit light, the light emitted from the lamp 80 (light including at least one of near-infrared light, visible light, and ultraviolet light) passes through the bottom wall 86 of the lamp housing 81 and is irradiated onto the upper surface of the substrate W. IPA, which is an example of a low surface tension liquid, transmits light with 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 passes through the liquid film L without being absorbed by the liquid film L. The light emitted from the outer surface of the lamp housing 81 (the lower surface of the bottom wall 86) passes through the liquid film L and is irradiated onto the upper surface of the substrate W. The area on the upper surface of the substrate W where the light is irradiated from the lamp unit 12 is called the irradiated area RR. As a result, the irradiated area RR is heated by radiation and increases in temperature. The irradiated region RR coincides with the heating region heated by the light irradiated from the lamp unit 12 in a plan view.

The light emitted from the lamp unit 12 raises the temperature of the surface layer of the substrate W (more specifically, the uneven pattern 960 shown in FIG. 2). The light irradiation heats the surface layer of the substrate W 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 irradiated region RR is heated and evaporated. As a result, a gas film of the low-surface tension liquid is formed around the surface of the substrate W (pattern surface 965 shown in FIG. 2). When the low-surface tension liquid is IPA, the boiling point is 82.6°C. With the irradiated region RR set on the upper surface of the substrate W, the third moving unit 35 moves the lamp unit 12 horizontally, so that the irradiated region RR moves within the upper surface of the substrate W.

The imaging unit IM (Figure 3) is a device that captures an image of the top surface of the substrate W. The imaging unit IM is installed, for example, at a position close to the inner surface of the side wall of the chamber 4 (Figure 1). The imaging unit IM has a camera CM and a light source LT. The camera CM is, for example, a digital camera having an imaging element such as a CCD (Charge Coupled Devices) or a CMOS (Complementary Metal Oxide Semiconductor). The light source LT is, for example, an LED. The imaging unit IM obtains a captured image of the top surface of the substrate W by irradiating light from the light source LT as necessary and capturing an image with the camera CM. The captured image is composed of multiple pixels, and each pixel has brightness value information.

The light source 84 (Figure 4) using an LED generally tends to deteriorate gradually with operation. This deterioration state may be evaluated based on an image captured by the camera CM. For example, light may be generated by the light source 84 and an image may be captured by the camera CM under predetermined conditions, and the deterioration state of the light source 84 may be evaluated from the brightness of the image. If it is evaluated that the intensity has decreased due to deterioration of the light source 84, the power to the light source 84 may be increased to compensate for this, thereby suppressing process fluctuations due to the deterioration. The timing of capturing images for this evaluation is arbitrary, but for example, images captured by the substrate processing method described below may be used for the evaluation.

Figure 6 is a block diagram showing the electrical configuration of the main parts of the substrate processing apparatus 1. The controller 3 includes a microcomputer and controls the control objects provided in the substrate processing apparatus 1 according to a predetermined control program. Specifically, the controller 3 includes a processor (CPU) 3A and a memory 3B in which the control program is stored. The controller 3 is configured to execute various controls for substrate processing by the processor 3A executing the control program. In particular, the controller 3 is programmed to control the transport robots IR and CR, the spin motor 23, the first moving unit 31, the second moving unit 33, the third moving unit 35, the guard lifting unit 74, the pin opening and closing unit 24, the heater energizing unit 64, the heater lifting unit 65, the lamp energizing unit 90, the pump 88d, the chemical liquid valve 50, the rinse liquid valve 51, the low surface tension liquid valve 52, the gas valve 53A, and the gas flow rate adjustment valve 53B. By controlling the valves by the controller 3, the presence or absence of ejection of liquid or gas from the corresponding nozzle and the ejection flow rate of gas from the corresponding nozzle are controlled.

<1-2. Basic Technology of Substrate Processing Method>
Fig. 7 is a flow diagram for explaining an example of substrate processing by the substrate processing apparatus 1. Fig. 7 mainly shows processing that is realized by the controller 3 executing a program. Figs. 8A to 8F are schematic diagrams for explaining the state of substrate processing. Figs. 9A to 9D are schematic diagrams for explaining an area 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 substrate processing by the substrate processing apparatus 1, for example, as shown in FIG. 7, a substrate loading process (step S11), a chemical liquid supply process (step S12), a rinsing liquid supply process (step S13), a substitution process (step S14), a liquid film formation process (step S15), a gas film formation process (step S16), a liquid film removal process (step S17), and a substrate unloading process (step S18) are performed.

First, the unprocessed substrate W is transported from the carrier C to the processing unit 2 by the transport robot CR and handed over to the spin chuck 5 (step S11). As a result, the substrate W is held horizontally by the spin chuck 5 (substrate holding process). The substrate W is held in a position in which the surface on which the uneven pattern 960 (see FIG. 2) is formed faces up. When the substrate W is loaded, power is supplied to the heater unit 6, and the heater unit 6 is retracted to the lower position. When the substrate W is loaded, the multiple guards 71 are retracted to the lower position. When the substrate W is loaded, 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 substrate W held horizontally is rotated (substrate rotation process). The holding of the substrate W by the spin chuck 5 and the rotation of the substrate W by the spin motor 23 continue until the liquid film removal process (step S17) is completed. The guard lifting unit 74 adjusts the height positions of the first guard 71A and the second guard 71B so that at least one guard 71 is in the upper position from the start of the substrate holding process to the end of the liquid film removal process (step S17).

Next, after the transport robot CR retreats to the outside of the processing unit 2, a chemical supply process (step S12) is started in which a chemical is supplied to the upper surface of the substrate W to process the upper surface of the substrate W with the chemical. Specifically, the first moving unit 31 moves the chemical nozzle 8 to a chemical processing position. The chemical processing position is, for example, a central position. With the chemical nozzle 8 positioned at the chemical processing position, the chemical valve 50 is opened. As a result, the chemical is supplied (discharged) from the chemical nozzle 8 toward the central portion of the upper surface of the substrate W in a rotating state (chemical supply process, chemical discharge process). The chemical discharged from the chemical nozzle 8 lands on the central portion of the upper surface of the substrate W. The centrifugal force caused by the rotation of the substrate W acts on the chemical that has landed on the upper surface of the substrate W. Therefore, the centrifugal force causes the chemical to spread over the entire upper surface of the substrate W, and the entire upper surface of the substrate W is thereby processed with the chemical. The supply of the chemical from the chemical nozzle 8 continues for a predetermined time, for example, 60 seconds. In the chemical supply process, the substrate W is rotated at a predetermined chemical rotation speed, for example, 1000 rpm.

After the chemical treatment for a predetermined time, a rinse process (step S13) is started to treat the upper surface of the substrate W with a rinse liquid. Specifically, the chemical valve 50 is closed, and the first moving unit 31 moves the chemical nozzle 8 to a retracted position. After the movement of the chemical nozzle 8 is started, the second moving unit 33 moves the rinse liquid nozzle 9 to a rinse processing position. The rinse processing position is, for example, a central position. With the rinse liquid nozzle 9 positioned at the rinse processing position, the rinse liquid valve 51 is opened. As a result, the rinse liquid is supplied (discharged) from the rinse liquid nozzle 9 toward the central part of the upper surface of the rotating substrate W (rinsing liquid supply process, rinsing liquid discharge process). The rinse liquid discharged from the rinse liquid nozzle 9 lands on the central part of the upper surface of the substrate W. The centrifugal force caused by 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 liquid spreads over the entire upper surface of the substrate W due to centrifugal force, thereby replacing the chemical liquid present on the upper surface of the substrate W with the rinse liquid. In other words, the entire upper surface of the substrate W is treated with the rinse liquid. The supply of the rinse liquid from the rinse liquid nozzle 9 continues for a predetermined time, for example, 15 seconds. In the rinse liquid supply process, the substrate W is rotated at a predetermined rinse liquid rotation speed, for example, 1000 rpm.

After the rinsing process has been performed for a predetermined period of time, a replacement process (step S14) is performed to replace the rinsing liquid present on the upper surface of the substrate W with a low surface tension liquid.

In the replacement process, 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 starts, 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 processing position is, for example, the central position.

With the low surface tension liquid nozzle 10 positioned at the low surface tension liquid processing position, the low surface tension liquid valve 52 is opened. 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 center 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 center of the upper surface of the substrate W. The centrifugal force caused by 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 due to the centrifugal force, and the rinsing liquid present 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 is covered with the low surface tension liquid. Simultaneously with the start of the supply of the low surface tension liquid or during the supply of the low surface tension liquid, the rotation of the substrate W is decelerated to a predetermined replacement speed (first rotation deceleration process). The replacement speed is, for example, 300 rpm.

During the supply of the low surface tension liquid, the heater lifting unit 65 moves the heater unit 6 from the lower position to the first heating position. The first heating position is a position higher than 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 is close to the lower surface of the substrate W without contacting it. Heating of the substrate W is started by placing the heater unit 6 at the first heating position. 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 located at the first heating position, the substrate W is heated to, for example, 30°C.

After the rinsing liquid present on the upper surface of the substrate W has been replaced with the low surface tension liquid, a liquid film formation process (step S15) is performed in which the supply of the low surface tension liquid is continued to form a liquid film L (see FIG. 8B) of the low surface tension liquid on the upper surface of the substrate W. After the rinsing liquid present on the upper surface of the substrate W has been replaced with the low surface tension liquid, the rotation of the substrate W is decelerated to a predetermined liquid film formation speed (second rotation deceleration process). The liquid film formation speed is a speed greater than 0 rpm and equal to or less than 50 rpm, for example, 10 rpm. In the second rotation deceleration process, the rotation of the substrate W may be decelerated in stages.

After the rotation of the substrate W is slowed down to the liquid film formation speed, the low surface tension liquid valve 52 is closed. This stops the supply of low surface tension liquid from the low surface tension liquid nozzle 10 to the upper surface of the substrate W. The supply of low surface tension liquid from the low surface tension liquid nozzle 10 continues for a predetermined time, for example, 30 seconds. By slowing down the rotation of the substrate W to the liquid film formation speed, the centrifugal force acting on the low surface tension liquid on the substrate W becomes smaller. Therefore, the discharge of low surface tension liquid from the substrate W is stopped. Alternatively, only a small amount of low surface tension liquid is removed from the substrate W. Therefore, even after the supply of low surface tension liquid to the upper surface of the substrate W is stopped, the upper surface of the substrate W remains covered with low surface tension liquid. As shown in FIG. 8B, the supply of the low surface tension liquid is stopped while the rotation of the substrate W is decelerated to the liquid film formation speed, so that the low surface tension liquid on the substrate W becomes sufficiently thick to form a puddle-like liquid film L (liquid film formation process, paddle formation process).

Even if a small amount of rinsing liquid remains in the recesses 962 of the uneven pattern 960 after the rinsing liquid has been replaced with the low surface tension liquid (see FIG. 2), this rinsing liquid dissolves in the low surface tension liquid and diffuses into the liquid film L. This makes it possible to reduce the amount of rinsing liquid remaining in the recesses 962 of the uneven pattern 960.

After the liquid film L is formed on the upper surface of the substrate W, a gas film formation process (step S16) is performed in which the substrate W is heated by irradiating light from the lamp unit 12 to form a gas film VL (see the enlarged view in Figure 8C) in the center of the upper surface of the substrate W.

With the liquid film L formed on the upper surface of the substrate W, as shown in FIG. 8C, the heater lifting unit 65 raises the heater unit 6 to the second heating position. The second heating position is a position above the first heating position and away 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 is close to the lower surface of the substrate W without contacting it. 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 placing the heater unit 6 at the second heating position, the entire substrate W is heated to a temperature higher than room temperature (e.g., 25°C) and lower than the boiling point of the low surface tension liquid (heater heating process). Therefore, the liquid film L is kept at a temperature higher than room temperature (e.g., 25°C) and lower than the boiling point of the low surface tension liquid (liquid film keeping process). When the heater unit 6 is located at the second heating position, the substrate W is heated to a higher temperature than when the heater unit 6 is located at the first heating position. When the heater unit 6 is located at the second heating position, if the opposing surface 6a of the heater unit 6 is heated to 195°C, 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 to place it at the light irradiation position. The light irradiation position is, for example, the central position. Furthermore, the third moving unit 35 moves the lamp unit 12 in the vertical direction so that the height position of the lamp unit 12 is the separated position. When the lamp unit 12 is located at the separated 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. With the height position of the lamp unit 12 at the separated position, the lamp current unit 90 energizes the lamp unit 12. This starts the irradiation of light from the lamp unit 12 (light irradiation process). The light irradiation is started while the liquid film insulation process is being performed. The light irradiation is started promptly (for example, 1.5 seconds later) after the liquid film L in the puddle 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 at the center 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. This warms the low surface tension liquid in contact with the irradiated region RR.

When the temperature of the irradiated region RR (i.e., the temperature of the uneven pattern 960 in the irradiated 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. As the low surface tension liquid in contact with the uneven pattern 960 in the irradiated region RR evaporates, a gas film VL of the low surface tension liquid (see the enlarged view in Figure 8C) is formed between the liquid film L and the substrate W. As a result, the liquid film L is held by the gas film VL in the irradiated region RR and rises above the upper surface of the substrate W.

If the temperature of the surface layer of the substrate W in the irradiated region RR is heated to a gas phase formation temperature equal to or higher than the boiling point of the low surface tension liquid, a gas film VL of sufficient thickness is formed in the irradiated region RR. When the low surface tension liquid is IPA, the boiling point is 82.6°C, and the gas film formation temperature is, for example, 100°C. A sufficient thickness means a thickness greater than the pattern height T1. If a gas film of sufficient thickness is formed, the liquid film L can be maintained at a sufficient height position by the gas film. A sufficient height position is a position where the interface between the liquid film L and the gas film VL is located above the tip surface 961b (see also FIG. 2) of the structure 961 of the uneven pattern 960.

After the gas film formation region VR is formed, a liquid film removal process is performed to remove the liquid film L from the upper surface of the substrate W while maintaining the gas film formation region VR in a formed state (step S17).

Specifically, even after the gas film formation region VR is formed, the irradiated region RR is maintained in the center of the upper surface of the substrate W by disposing the lamp unit 12 at the light irradiation position. Therefore, even after the gas film formation region VR is formed, the heating of the center of the upper surface of the substrate W by the lamp unit 12 is maintained. By maintaining the heating of the center of the upper surface of the substrate W, evaporation of the processing liquid held in the gas film VL in the center of the upper surface of the substrate W is promoted.

Furthermore, by maintaining heating at the center of the upper surface of the substrate W, a large temperature difference occurs between the irradiated region RR and the non-irradiated region NR on the upper surface of the substrate W. Due to this temperature difference, a thermal convection current flows from the center to the periphery on the upper surface of the substrate W. As the substrate W rotates, a centrifugal force acts on the liquid film L.

Because the rotation speed of the substrate W is the paddle speed, the centrifugal force acting on the liquid film L is relatively weak. Also, the thermal convection generated on the upper surface of the substrate W is relatively weak. However, as described above, the frictional resistance acting on the liquid film L in the gas film formation region VR is so small that it can be considered to be zero. Therefore, the low surface tension liquid is pushed outward by these centrifugal forces and thermal convection. As a result, the thickness of the central part of the liquid film L is reduced, and as shown in FIG. 8D, a substantially circular opening 100 is formed in the central part of the liquid film L. The opening 100 is an exposure hole that exposes the upper surface of the substrate W. By forming the opening 100, the liquid film L is partially removed, and the gas film formation region VR has a circular ring shape as shown in FIG. 9B. The irradiated region RR is circular. By forming the opening 100, a gas-liquid interface GL is formed between the liquid film L in the gas film formation region VR and the opening 100, that is, at the inner periphery of the liquid film L in the gas film formation region VR, as shown in the enlarged view of FIG. 8D.

In this way, the evaporation of the treatment liquid, the generation of thermal convection, and the action of centrifugal force remove the low surface tension liquid held by the gas film VL, as shown in FIG. 8D, and an opening 100 is quickly formed in the center of the liquid film L (opening formation process). The formation of the opening 100 causes the liquid film L to be annular. The formation of the opening 100 also causes the liquid film formation region LR to be annular, as shown in FIG. 9B.

Even after the gas film VL is formed, the heater unit 6 continues to heat the substrate W, and the entire liquid film L is kept warm (liquid film warming process). This makes it possible to prevent the gas film VL from disappearing when the opening 100 is formed.

The substrate W is heated by the heater unit 6 and the lamp unit 12 even after the opening 100 is formed in the liquid film L. Since there is no low surface tension liquid in the region (opening formation region OR) where the opening 100 is formed on the upper surface of the substrate W, the temperature of the substrate W is quickly increased by the heater unit 6 and the lamp unit 12. As a result, a temperature difference occurs between the inside of the inner periphery of the liquid film L (opening formation region OR) and the outside of the inner periphery of the liquid film L (liquid film formation region LR). Specifically, the temperature of the substrate W is high in the opening formation region OR and low in the liquid film formation region LR. This temperature difference causes thermal convection to continue to occur near the inner periphery of the liquid film L. In addition, because the substrate W is rotating, centrifugal force acts on the liquid film L. Therefore, the opening 100 is enlarged by the action of centrifugal force and the occurrence of thermal convection, as shown in Figures 8D and 8E (opening enlargement process).

After the opening 100 is formed, as shown by the two-dot chain line in FIG. 8D, the third moving unit 35 changes the height position of the lamp unit 12 to a proximity position that is closer to the upper surface of the substrate W than the separated position (irradiation unit proximity process). This makes it possible to quickly increase the temperature of the opening formation region OR on the upper surface of the substrate W. When the lamp unit 12 is located at the proximity 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 begins, the third moving unit 35 moves the low surface tension liquid nozzle 10, the gas nozzle 11 and the lamp unit 12 toward the peripheral edge of the substrate W while maintaining the height position of the lamp unit 12 in a close position (close 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 positioned inside the substrate W relative to the lamp unit 12, i.e., so that the gas nozzle 11 faces the opening formation region OR. As the lamp unit 12 moves toward the peripheral edge of the upper surface of the substrate W, the irradiated region RR moves toward the peripheral edge of the upper surface of the substrate W.

Even while the opening 100 is being expanded, the substrate W is rotated. Therefore, the irradiated region RR moves relatively upstream 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 a gas film VL of sufficient thickness is formed all around the inner peripheral edge of the liquid film L. That is, as shown in FIG. 9C, while the opening 100 is being expanded, the gas film formation region VR becomes annular. While the opening 100 is being expanded, the gas film VL is also formed in the non-irradiated region NR. Thus, in the opening expansion process, the irradiated region RR is moved toward the peripheral portion 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 gas film VL is formed on the inner peripheral edge of the liquid film L.

As shown in FIG. 9C, the irradiated region RR is moved in accordance with the expansion of the opening 100 so that it is positioned across the liquid film formation region LR and the opening formation region OR. This allows the inner edge of the liquid film L to be heated with a sufficient amount of heat. This prevents a situation in which a gas film VL is not formed at the inner edge of the liquid film L due to insufficient heat, or a situation in which the gas film VL once formed disappears and the low surface tension liquid comes into contact with the upper surface of the substrate W. In other words, a gas film VL can be stably formed at the inner edge of the liquid film L.

Although the movement of the low surface tension liquid by thermal convection can enlarge the opening 100 to a certain extent, as shown in Figures 8F and 9D, when the outer periphery of the opening 100 reaches the peripheral portion of the upper surface of the substrate W, the movement of the low surface tension liquid may stop. More specifically, when the outer periphery of the opening 100 reaches the peripheral portion of the upper surface of the substrate W, the total amount of processing liquid on the substrate W is small, so the temperature difference of the substrate W inside and outside the opening 100 becomes small. Therefore, the low surface tension liquid is in an equilibrium state in which it repeatedly moves inside and outside the substrate W. In this case, when the low surface tension liquid returns to the inside of the substrate W, the low surface tension liquid may directly contact the upper surface of the substrate W from which the gas film VL has been lost. Therefore, there is a risk of pattern collapse due to the surface tension of the low surface tension liquid or particles due to insufficient drying. When the opening 100 is enlarged, the substrate W is rotating. Therefore, if the centrifugal force acting on the liquid film L is sufficiently large, this equilibrium state can be resolved. However, if the centrifugal force is not sufficiently large, 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 edge of the liquid film L reaches the peripheral portion of the upper surface of the substrate W, the gas valve 53A is opened. As a result, gas is sprayed toward the opening formation region OR, as shown in FIG. 8F. 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 outward from the substrate W, promoting the expansion of the opening 100 (expansion promotion process). As a result, the low surface tension liquid is removed from the upper surface of the substrate W without stopping. Pattern collapse and particle generation can be suppressed or prevented.

The liquid film L is finally completely removed from the upper surface of the substrate W by the expansion of the opening 100. After that, the supply of power from the lamp power supply 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 lifting unit 74 moves the first guard 71A and the second guard 71B to the lower position. Then, the heater lifting unit 65 moves the heater unit 6 to the lower position. The transport robot CR enters the processing unit 2, scoops up the processed substrate W from the chuck pins 20 of the spin chuck 5, and transports it out of the processing unit 2 (step S18). The substrate W is handed over from the transport robot CR to the transport robot IR, which stores it in the carrier C.

According to the first embodiment, light is irradiated to an irradiation region RR set in the central portion of the upper surface of the substrate W, and the central portion of the upper surface of the substrate W is heated. As a result, the low surface tension liquid in contact with the central portion of the upper surface of the substrate W evaporates, and a gas film VL is formed in the central portion of the upper surface of the substrate W. As the gas film VL is formed, a liquid film L rises 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 removing the low surface tension liquid held by the gas film VL formed in the central portion of the upper surface of the substrate W.

After the opening 100 is formed, the substrate W is rotated while the irradiated region RR is moved toward the peripheral edge of the upper surface of the substrate W, thereby enlarging the opening 100 while maintaining the state in which the gas film VL is formed on the inner edge of the liquid film L. In other words, when the liquid film L is removed from the upper surface of the substrate W, the annular region in which the gas film VL is formed (gas film formation region VR) moves toward the peripheral edge of the upper surface of the substrate W as the opening 100 enlarges. The gas film formation region VR moves on the substrate W so that the inner and outer edges become larger.

As a method of forming and enlarging an opening in the liquid film L to remove the liquid film L from the upper surface of the substrate, a method of removing the liquid film L from the substrate W while keeping the heater unit 6 in contact with the lower surface of the substrate W, which is different from the present embodiment, and a method of removing the liquid film L from the substrate W while heating the entire upper surface of the substrate W with a lamp unit (a lamp unit different from that of the first embodiment) facing the entire upper surface of the substrate W, are conceivable. When these methods are adopted, it is necessary to maintain the state in which the gas film VL is formed at the location on the upper surface of the substrate W where the liquid film L is finally removed, for a long period from the start to the end of the removal of the liquid film L.

On the other hand, in this embodiment 1, the annular gas film formation region VR is expanded together with the opening 100. Therefore, compared to a method in which the liquid film L held in the gas film VL is removed after the gas film VL is formed over the entire upper surface of the substrate W, the time from when the gas film VL is formed to when the low surface tension liquid held in the gas film VL is removed can be shortened at any point on the upper surface of the substrate W. This makes it possible to prevent the entire substrate W from being heated excessively (for a long period of time) when the opening 100 is formed and expanded. Therefore, it is possible to prevent the low surface tension liquid from evaporating locally and causing the liquid film L to split.

The longer the heating time to maintain the gas film VL, the greater the possibility that the gas film VL will disappear due to a local drop in temperature of the liquid film L or the substrate W. In this embodiment 1, however, the time from when the gas film VL is formed to when the low surface tension liquid held in the gas film VL is eliminated is shortened at any point on the upper surface of the substrate W. This makes it possible to suppress pattern collapse caused by heating to maintain the gas film VL for a long period of time.

The opening 100 is formed and enlarged while the low surface tension liquid is kept warm by the heater unit 6. This allows the gas film VL to be formed quickly in the irradiated region RR. This also allows the temperature of the substrate W to be prevented from dropping in the non-irradiated region NR (particularly the region on the opposite side of the irradiated region RR with respect to the rotation center position of the top surface of the substrate W). This prevents the formed gas film VL from moving outside the irradiated region RR (downstream in the rotation direction from the irradiated region RR) and disappearing.

As a result, the low surface tension liquid can be effectively removed from the top surface of the substrate W. As a result, pattern collapse due to the surface tension of the low surface tension liquid and particle generation due to insufficient drying can be suppressed.

In addition, according to the first embodiment, in the liquid film insulation process, the substrate W is heated by the heater unit 6 arranged at a position (second heating position) spaced apart 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 is configured not to rotate together with the substrate, the substrate W can be easily rotated when the opening 100 is enlarged. In addition, compared to a configuration in which the heater unit 6 contacts the substrate W, the entire substrate W can be moderately heated. In addition, the transfer of dirt adhering to the heater unit 6 to the substrate W can be suppressed. Furthermore, since there is no need to precisely adjust the parallelism between the facing surface 6a and the lower surface of the substrate W as in the configuration in which the heater unit 6 contacts the substrate W, the complication of the substrate processing apparatus 1 can be avoided.

In addition, by blowing gas onto the opening formation region OR on the upper surface of the substrate W while the opening 100 is being expanded, the opening formation region OR may be cooled. If the opening formation region OR is cooled, the temperature difference between the liquid film formation region LR and the opening formation region OR on the upper surface of the substrate W may be insufficient, and thermal convection may not be sufficiently formed within the liquid film L. This may hinder the expansion of the opening 100. Therefore, in this embodiment 1, in the opening expansion process, gas is not blown onto the upper surface of the substrate W until the inner edge of the liquid film L reaches the peripheral portion of the upper surface of the substrate W. Therefore, cooling of the opening formation region OR on the upper surface of the substrate W due to blowing gas can be avoided.

<1-3. Technology for suppressing variation in substrate processing methods>
Steps S11 to S18 (FIG. 7) of the substrate processing method are repeated to process a plurality of substrates W. A technique for suppressing the variation in step S17 will be described. According to this technique, which will be described in detail later, a situation occurring in the substrate processing of a certain substrate is referred to in setting conditions for the substrate processing of at least one other substrate (typically a plurality of substrates), thereby suppressing process variation in the substrate processing. In the following, the above-mentioned "specific substrate" may be referred to as a reference substrate (or a first substrate W), and the above-mentioned "at least one other substrate" may be referred to as a normal substrate (or a second substrate W). Furthermore, the substrate processing of the reference substrate may be referred to as a reference substrate processing, and the above-mentioned substrate processing of the normal substrate may be referred to as a normal substrate processing. The reference substrate and the normal substrate may have a substantially common configuration. Furthermore, the reference substrate processing and the normal substrate processing may be substantially common substrate processing, except for the difference in parameter values of the processing conditions.

First, step 100h (Fig. 10) is performed as a part of steps S14 to S17 (Fig. 7) for the reference substrate processing (substrate processing of the substrate W as the reference substrate). The specific method is described below.

In step S101h (FIG. 10), a liquid film L of a low surface tension liquid (organic solvent) is formed on the first substrate W, which is the reference substrate (see FIG. 8B). In other words, the above-mentioned step S15 (FIG. 7) is performed on the first substrate W. Note that, hereinafter, the liquid film L formed on the first substrate W may be referred to as the first liquid film L.

Next, in step S102h (FIG. 10), the first substrate W is heated to form a gas film VL that holds the first liquid film L (see FIG. 8C). In other words, the above-mentioned step S16 (FIG. 7) is performed on the first substrate W. Note that, hereinafter, the gas film VL that holds the first liquid film L may be referred to as the first gas film VL. Step S102h (FIG. 10) includes step S102hL of irradiating the first substrate W with light from the lamp unit 12 (FIG. 8C) in order to heat the substrate W.

In step S103h (FIG. 10), the first stage of step S17 (FIG. 7) described above is performed on the first substrate W. Specifically, light is irradiated from the lamp unit 12 (FIG. 8D) onto the upper surface S2 (FIG. 12) of the first substrate W under predetermined conditions (first conditions), and an opening 100 (FIG. 8D) is formed as a hole OP (FIG. 12) in the first liquid film L held in the first gas film VL. In the following, the hole OP formed in the first liquid film L may be referred to as the first hole OP. The first conditions include a setting condition for the intensity of the light irradiated onto the first substrate W and a setting condition for the irradiated region RR, which is the portion of the first substrate W that is irradiated with the light.

Next, in step S104h (FIG. 10), the second stage of step S17 (FIG. 7) described above is performed on the first substrate W. In other words, light is irradiated onto the first substrate W under a second predetermined condition different from the first condition described above. Specifically, the second condition includes an operating condition in which the first substrate W is rotated as shown by the arrow RT (FIG. 13) while shifting the irradiated region RR from the center of the substrate W along the scan direction CN (FIG. 13). This causes the first hole OP to be expanded as shown by the arrow in FIG. 12. The expanded first hole OP is photographed using the camera CM (FIG. 3) to obtain a hole image OQ (first image) (step S105h (FIG. 10)). This hole image OQ is then stored as a reference image (step S111h (FIG. 10)).

The above-mentioned acquisition of the hole image OQ is performed, for example, when a predetermined time has elapsed from a reference point in time. The reference point in time is a specific point in time in the substrate processing method, and in this embodiment 1, may be the point in time when scanning of the irradiated region RR begins.

Next, the third stage of step S17 (FIG. 7) described above is performed on the first substrate W. Specifically, the first hole OP is further enlarged by irradiating the first substrate W with light under a third predetermined condition (step S121h (FIG. 10)). The third condition may include a setting condition for the intensity of the light irradiated to the first substrate W. The third condition may also include a setting condition for the moving speed of the irradiated region RR from the center to the outer periphery of the first substrate W (in other words, the scanning speed of the lamp unit 12 (FIG. 8E)). The third condition may also include a setting condition for the rotation speed of the first substrate W. Finally, the irradiated region RR is moved until it reaches the outer periphery of the substrate W (see FIG. 9D), thereby removing most of the IPA liquid film L from the upper surface S2.

Next, the fourth stage of step S17 (FIG. 7) described above is performed on the first substrate W. Specifically, gas is blown toward the opening formation region OR (see FIG. 8F). This removes the IPA liquid film L from the upper surface S2.

This completes the drying process (step S100h (FIG. 10)) for the first substrate W as the reference substrate. In other words, the reference substrate process (processing for the reference substrate) ends.

After the above-mentioned reference substrate processing (step S100h (FIG. 10)), step S100i (FIG. 11) is performed as normal substrate processing (substrate processing of the second substrate W as a normal substrate). Typically, after the reference substrate processing is performed once on one reference substrate, the normal substrate processing is repeated multiple times to process a large number of normal substrates. Details of step S100i are described below.

First, step S101i (FIG. 11) is performed in the same manner as step S101h (FIG. 10) described above. As a result, a liquid film L of a low surface tension liquid (organic solvent) is formed on the second substrate W, which is a normal substrate (see FIG. 8B). Note that, hereinafter, the liquid film L formed on the second substrate W may be referred to as the second liquid film L.

Next, step S102i (FIG. 11) is performed in the same manner as step S102h (FIG. 10) described above, thereby heating the second substrate W. As a result, a gas film VL that holds the second liquid film L is formed (see FIG. 8C). Note that, hereinafter, the gas film VL that holds the second liquid film L may be referred to as the second gas film VL. Step S102i (FIG. 11) includes step S102iL of irradiating the substrate W with light from the lamp unit 12 (FIG. 8C) in order to heat the second substrate W.

Next, step S103i (FIG. 11) is performed in the same manner as step S103h (FIG. 10) described above. Specifically, a hole OP is formed in the center of the second liquid film L held by the second gas film VL by irradiating the second substrate W with light under the first condition described above. Note that, hereinafter, the hole OP formed in the second liquid film L may be referred to as the second hole OP.

Next, step S104i (FIG. 11) is performed in the same manner as step S104h (FIG. 10) described above. Specifically, the second hole OP is enlarged by irradiating the second substrate W with light under the second condition described above.

Next, step S105i (Fig. 11) is performed in the same manner as step S105h (Fig. 10) described above. Specifically, the second hole OP (Fig. 13) expanded by step S104i above is photographed by the camera CM (Fig. 3). This results in an image (second image) of the expanded second hole OP (Fig. 13).

Next, in step S111i (FIG. 11), referring to FIG. 13, the first hole represented by the hole image OQ (first image) as the reference image is compared with the second hole OP represented by the second image. This allows the progress of the expansion of the second hole OP to be evaluated. This comparison may be performed by an image comparison unit (not shown) configured by the controller 3. The above-mentioned steps S104h (FIG. 10) and S104i (FIG. 11) are both processes set to the second condition, but in reality, due to the influence of process fluctuations, differences may occur between the first hole OP by step S104h and the second hole OP by step S104i.

Next, in step S112i (FIG. 11), the third condition for irradiating the second substrate W with light is adjusted based on the progress of the expansion of the second hole OP evaluated as described above. This adjustment may be performed by a condition adjustment unit (not shown) configured by the controller 3.

In the above comparison, for example, as shown in FIG. 13, the area AQ (a dotted area in FIG. 13) of the first hole represented by the hole image OQ (first image) may be compared with the area AP (a hatched area in FIG. 13) of the second hole OP in the second image (FIG. 13). In the example shown in FIG. 13, each of the areas AQ and AP is calculated in the irradiated area RR at the time of shooting, not for the entire upper surface S2 of the substrate W. Therefore, the above comparison is performed within the irradiated area RR. The irradiated area RR at the time of shooting may be calculated from the operating conditions of the third moving unit 35 (FIG. 3) for scanning the lamp unit 12. When the area AP is larger than the area AQ, the third condition is adjusted so that the expansion of the hole OP is suppressed. Specifically, as an adjustment of the third condition, for example, the intensity of the light irradiated to the second substrate W is adjusted to be smaller. Alternatively, for example, the movement speed (scanning speed) of the irradiated region RR is adjusted to be slower. Alternatively, the rotation speed of the second substrate W is adjusted to be slower. The amount of adjustment in these adjustments may be a predetermined amount, or may be an amount corresponding to the difference between the areas AQ and AP. Conversely, when the area AP is smaller than the area AQ, the third condition is adjusted to promote the expansion of the hole OP.

As a modified example of the above comparison method described with reference to FIG. 13, for example, as shown in FIG. 14, the dimension of the first hole represented by the hole image OQ (first image) (dimension from the reference point P1 to the end point PQ) may be compared with the dimension of the second hole OP in the second image (FIG. 14) (dimension from the reference point P1 to the end point PP). In the example shown in FIG. 14, each dimension is calculated in the detection section LE extending outward from the reference point P1. The detection section LE is preferably within the irradiated region RR at the time of shooting, preferably along the scanning direction CN, and if the irradiated region RR has a circular shape, it may be the diameter of the circle along the scanning direction CN. If the dimension of the hole OP (dimension from the reference point P1 to the end point PP) is larger than the dimension of the hole image OQ (dimension from the reference point P1 to the end point PQ), the third condition is adjusted so that the expansion of the second hole OP is suppressed. Conversely, if the dimension of the second hole OP (the dimension from the reference point P1 to the end point PP) is smaller than the dimension of the hole image OQ (the dimension from the reference point P1 to the end point PQ), the third condition is adjusted to promote the expansion of the second hole OP. The amount of adjustment may be a predetermined amount, or may be an amount corresponding to the magnitude of the difference in dimensions described above.

Next, the second hole OP is further expanded (step S121i (FIG. 11)) by irradiating the second substrate W with light under the third condition adjusted in step S112i (FIG. 11). Finally, the irradiated region RR is moved until it reaches the outer periphery of the substrate W (see FIG. 9D), thereby removing most of the IPA liquid film L from the upper surface S2.

Next, as in the case of the first substrate W, gas is blown toward the opening formation region OR (FIG. 8F) of the second substrate W. This removes the IPA liquid film L from the upper surface S2.

This completes the drying process (step S100i (FIG. 11)) for the second substrate W as a normal substrate. In other words, the normal substrate processing (processing for a normal substrate) ends.

<1-4. Effects>
According to the first embodiment, the progress of the expansion of the second hole OP caused by irradiating the second substrate W as a normal substrate with light under the predetermined condition (second condition) is evaluated based on the progress of the expansion of the first hole OP caused by irradiating the first substrate W as a reference substrate with light under the predetermined condition (second condition). By adjusting the condition (third condition) for further irradiating the second substrate W as a normal substrate with light based on this progress, the progress speed of the further expansion of the second hole OP can be made closer to the standard progress speed. This makes it possible to suppress the variation in the progress speed of the expansion of the second hole OP of the second liquid film L on the upper surface S2 of the second substrate W as a normal substrate. Therefore, it is possible to suppress the adverse effect on the upper surface S2 of the second substrate W (normal substrate) caused by the variation. Specifically, it is possible to suppress the collapse of the pattern 960 provided on the upper surface S2 of the normal substrate.

Since light is irradiated onto the substrate W from above, the lamp unit 12 is positioned above the substrate W. This makes it difficult for the chemical liquid discharged onto the substrate W to adhere to the lamp unit 12 and its associated members. This makes it possible to avoid damage caused by the chemical liquid to the lamp unit 12 and its associated members. This effect is particularly significant when a highly corrosive chemical liquid such as hydrofluoric acid is used.

The third condition may include a setting condition for the intensity of light irradiated onto the normal substrate. The third condition may include a setting condition for the scanning speed of the irradiated region RR. The third condition may include a setting condition for the rotation speed of the normal substrate. By using at least one of these setting conditions, the progress speed of the further expansion of the second hole OP of the second liquid film L on the second substrate W (normal substrate) can be effectively adjusted.

The comparison between the first hole OP of the reference substrate and the second hole OP of the normal substrate (FIG. 11: step S111i) for evaluating the progress may be performed within the irradiated region RR (see FIG. 13 or FIG. 14). This can increase the reliability of the evaluation.

The comparison between the first hole OP of the reference board and the second hole OP of the normal board to evaluate the progress (FIG. 11: step S111i) may be performed by comparing the area AQ of the hole image OQ of the reference board and the area AP of the hole OP of the normal board, as shown in FIG. 13. In this case, it is possible to average out the effects of expansion in various directions and perform an evaluation. Alternatively, the comparison between the first hole OP of the reference board and the second hole OP of the normal board to evaluate the progress may be performed by comparing the dimensions of the hole image OQ of the reference board and the hole OP of the normal board, as shown in FIG. 14. In this case, evaluation can be performed in a simple manner.

It is preferable to evaluate the deterioration state of the light source 84 (FIGS. 4 and 5) of the lamp unit 12 based on the image captured by the camera CM (FIG. 3). This makes it possible to suppress variation in the rate at which the hole OP expands due to irradiation with light from the light source 84.

<2. Second embodiment>
<2-1. Configuration of the substrate processing apparatus>
In the second embodiment, a substrate processing apparatus 1 (FIG. 1) is provided with a processing unit 2A (FIG. 15) instead of the processing unit 2 (FIG. 1). FIG. 15 is a schematic diagram of the inside of the processing unit 2A viewed horizontally, and FIG. 16 is a schematic diagram of the spin base 116 and related configurations viewed from above. FIG. 17 is a schematic vertical cross-sectional view of the upper surface head 130 shown in FIG. 15. FIG. 18 is a schematic diagram of the upper surface head 130 viewed from below. FIG. 19 is a schematic vertical cross-sectional view of the second lamp heater 172. FIG. 20 is a schematic diagram of the second lamp heater 172 viewed from below.

As shown in FIG. 15, the processing unit 2A is a wet processing unit that supplies processing liquid to the substrate W. The processing unit 2A includes a box-shaped chamber 4 having an internal space, a spin chuck (substrate holding unit) 105 that holds one substrate W horizontally in the chamber 4 and rotates it about a vertical rotation axis A1 that passes through the center of the substrate W, a plurality of nozzles 131-135 that eject processing fluids (processing liquid and processing gas) toward the substrate W held on the spin chuck 105, a first heating unit 151 and a second heating unit 171 for heating the substrate W from above by irradiating it with light, and a cylindrical processing cup 107 that surrounds the spin chuck 105 about the rotation axis A1.

15, the chamber 4 includes a box-shaped partition 111 having an entrance 4A through which the substrate W passes, and a shutter unit 4B for opening and closing the entrance 4A. The FFU 113 (fan filter unit) is disposed on an air outlet 111a disposed on the upper part of the partition 111. The FFU 113 constantly supplies clean air (air filtered by a filter) to the inside of the chamber 4 from the air outlet 111a. The gas in the chamber 4 is discharged from the chamber 4 through an exhaust duct 114 connected to the bottom of the processing cup 107. This constantly creates a downflow of clean air inside the chamber 4. The flow rate of the exhaust air discharged to the exhaust duct 114 is changed according to the opening degree of an exhaust valve 115 disposed in the exhaust duct 114.

15, the spin chuck 105 includes a disk-shaped spin base 116 held in a horizontal position, a plurality of chuck pins 117 that hold the substrate W in a horizontal position above the spin base 116, and a spin shaft 118 that extends vertically downward along the rotation axis A1 from the center of the spin base 116. The spin shaft 118 is rotated around the rotation axis A1 by a spin motor (substrate rotation unit) 119. When the spin base 116 and the plurality of chuck pins 117 are rotated, the plurality of chuck pins 117 rotate around the rotation axis A1. The plurality of chuck pins 117 are arranged at intervals in the circumferential direction on the outer periphery of the upper surface 116u of the spin base 116. The plurality of chuck pins 117 can be opened and closed between a closed state in which the plurality of chuck pins 117 contact the peripheral edge of the substrate W to grip the substrate W, and an open state in which the plurality of chuck pins 117 are retracted from the peripheral edge of the substrate W. In the open state, the multiple chuck pins 117 contact the lower surface of the outer periphery of the substrate W to support the substrate W from below. A chuck pin drive unit 120 for driving the chuck pins 117 to open and close is coupled to the chuck pins 117. The chuck pin drive unit 120 includes, for example, a link mechanism housed inside the spin base 116 and a drive source disposed outside the spin base 116. The drive source includes an electric motor. A specific configuration example of the chuck pin drive unit 120 is described in JP 2008-034553 A and the like.

The spin chuck 105 is not limited to a gripping type, and may be, for example, a vacuum chuck type (vacuum chuck) that holds the substrate W in a horizontal position by vacuum suctioning the back surface of the substrate W and then rotates the substrate W held by the spin chuck 105 around a vertical axis of rotation.

The multiple nozzles include a chemical liquid nozzle 131 that ejects a chemical liquid toward the upper surface of the substrate W, a rinsing liquid nozzle 132 that ejects a rinsing liquid toward the upper surface of the substrate W, an organic solvent nozzle (treatment liquid nozzle) 133 that ejects an organic solvent (more generally, a low surface tension liquid) toward the upper surface of the substrate W, a first gas nozzle 134 that ejects a gas toward the upper surface of the substrate W, and a second gas nozzle 135 that ejects a gas toward the upper surface of the substrate W.

The chemical nozzle 131 is connected to a chemical pipe 136 that guides the chemical to the chemical nozzle 131. When a chemical valve 137 installed in the chemical pipe 136 is opened, the chemical is continuously discharged downward from the discharge port of the chemical nozzle 131. The chemical discharged from the chemical nozzle 131 may be a liquid containing at least one of sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid, phosphoric acid, acetic acid, ammonia water, hydrogen peroxide, organic acid (e.g., citric acid, oxalic acid, etc.), organic alkali (e.g., TMAH: tetramethylammonium hydroxide, etc.), surfactant, and corrosion inhibitor, or may be other processing liquid.

15 and 16, the chemical nozzle 131 is a movable scan nozzle. The processing unit 2A includes a first arm 140 having the chemical nozzle 131 attached to its tip, and a first moving device 139 that moves the chemical nozzle 131 by moving the first arm 140. As shown in FIG. 16, the first moving device 139 rotates the first arm 140 around a rotation axis A2 that extends vertically around the spin chuck 105, thereby moving the chemical nozzle 131 horizontally along a trajectory that passes through the center of the upper surface of the substrate W in a planar view. The first moving device 139 moves the chemical nozzle 131 between a processing position where the chemical discharged from the chemical nozzle 131 lands on the upper surface of the substrate W and a retracted position (position shown in FIG. 16) where the chemical nozzle 131 is retracted around the spin chuck 105 in a planar view. The first moving device 139 includes, for example, an electric motor.

As shown in FIG. 15, the rinse liquid nozzle 132 is connected to a rinse liquid pipe 141 that guides the rinse liquid to the rinse liquid nozzle 132. When a rinse liquid valve 142 disposed in the rinse liquid pipe 141 is opened, the rinse liquid is continuously discharged downward from the discharge port of the rinse liquid nozzle 132. The rinse liquid discharged from the rinse liquid nozzle 132 is, for example, pure water (deionized water: DIW (Deionized Water)). The rinse liquid may be any of carbonated water, electrolytic ionized water, hydrogen water, ozone water, hydrochloric acid water with a diluted concentration (for example, about 10 ppm to 100 ppm), and ammonia water with a diluted concentration (for example, about 10 ppm to 100 ppm).

15 and 16, the rinse liquid nozzle 132 is a movable scan nozzle. The processing unit 2A includes a second arm 143 to which the rinse liquid nozzle 132 is attached at the tip, and a second moving device 144 that moves the rinse liquid nozzle 132 by moving the second arm 143. As shown in FIG. 16, the second moving device 144 moves the rinse liquid nozzle 132 along a trajectory passing through the center of the upper surface of the substrate W in a planar view by rotating the second arm 143 around a rotation axis A3 extending vertically around the spin chuck 105. The second moving device 144 moves the rinse liquid nozzle 132 between a processing position where the rinse liquid discharged from the rinse liquid nozzle 132 lands on the upper surface of the substrate W and a retracted position (position shown in FIG. 16) where the rinse liquid nozzle 132 is retracted around the spin chuck 105 in a planar view. The second movement device 144 includes an electric motor.

As shown in FIG. 15, the organic solvent nozzle 133 is connected to an organic solvent pipe 145 that guides the organic solvent to the organic solvent nozzle 133. When an organic solvent valve 146 installed in the organic solvent pipe 145 is opened, the organic solvent is continuously discharged downward from the organic solvent outlet 133a of the organic solvent nozzle 133. The organic solvent discharged from the organic solvent nozzle 133 is, for example, IPA (isopropyl alcohol). Examples of organic solvents that can be used other than IPA include methanol, ethanol, acetone, EG (ethylene glycol), HFE (hydrofluoroether), n-butanol, t-butanol, isobutyl alcohol, and 2-butanol. In addition, the organic solvent can be not only a single component, but also a liquid mixed with other components. The organic solvent nozzle 133, the organic solvent pipe 145, and the organic solvent valve 146 constitute an organic solvent supply unit (processing liquid supply unit). In this embodiment, the organic solvent nozzle 133 is integrated with a first lamp heater 152, which will be described later.

The first gas nozzle 134 is connected to a first gas pipe 147 that guides gas to the first gas nozzle 134. When a first gas valve 148 interposed in the first gas pipe 147 is opened, gas is continuously discharged downward from the first gas outlet 134a of the first gas nozzle 134 at a flow rate corresponding to the opening degree of a first flow rate adjustment valve 149 that changes the flow rate of the gas. The gas supplied to the first gas nozzle 134 is an inert gas such as nitrogen gas. The inert gas may be a gas other than nitrogen gas, such as helium gas or argon gas. The first gas nozzle 134, the first gas pipe 147, the first gas valve 148, and the first flow rate adjustment valve 149 constitute a first spray unit for spraying gas onto the upper surface of the substrate W held by the spin chuck 105. The first gas nozzle 134 is attached to and supported by the first lamp heater 152, which will be described later.

The second gas nozzle 135 is connected to a second gas pipe 197 that guides gas to the second gas nozzle 135. When a second gas valve 198 interposed in the second gas pipe 197 is opened, gas is continuously discharged downward from the second gas outlet 135a of the second gas nozzle 135 at a flow rate corresponding to the opening degree of a second flow rate adjustment valve 199 that changes the flow rate of the gas. The gas supplied to the second gas nozzle 135 is an inert gas such as nitrogen gas. The inert gas may be a gas other than nitrogen gas, such as helium gas or argon gas. The second gas nozzle 135, the second gas pipe 197, the second gas valve 198, and the second flow rate adjustment valve 199 constitute a second spray unit for spraying gas onto the upper surface of the substrate W held by the spin chuck 105. The second gas nozzle 135 is attached to and supported by the second lamp heater 172, which will be described later.

The first heating unit 151 includes a first lamp heater 152 and a first heater moving unit (a third moving device 163 described later) that moves the first lamp heater 152. As shown in FIG. 17, the first lamp heater 152 is a radiation heater that irradiates light including at least one of near-infrared rays, visible rays, and ultraviolet rays toward the substrate W and heats the substrate W by radiation. The first lamp heater 152 includes a first lamp 154, a first lamp housing 155 that houses the first lamp 154, and a first heat sink 156 for cooling the inside of the first lamp housing 155.

17 and 18, the first lamp 154 includes a disk-shaped first lamp substrate 157 and a plurality of first light sources 158 (52 in the example of FIG. 18) mounted on the underside of the first lamp substrate 157. Each of the first light sources 158 is, for example, an LED (light-emitting diode). As shown in FIG. 18, the plurality of first light sources 158 are distributed and arranged over the entire area of the underside of the first lamp substrate 157. In the example of FIG. 18, 52 first light sources 158 are arranged in a triple annular shape. The arrangement density of the first light sources 158 on the first lamp substrate 157 is approximately uniform. The plurality of first light sources 158 form a first light-emitting portion 154A in the shape of a ring having a horizontal extension. The first light-emitting portion 154A surrounds the periphery of the organic solvent discharge port 133a in an annular shape when viewed from below. The light emitted from each first light source 158 includes at least one of near infrared light, visible light, and ultraviolet light. The wavelength of the light emitted from each first light source 158 is in the range of 200 nm to 1100 nm, and more preferably in the range of 390 nm to 800 nm.

As shown in FIG. 17, the first lamp housing 155 includes a cylindrical first housing body 159 and a disk-shaped first bottom wall 160. The first housing body 159 is formed of a chemically resistant material such as PTFE (polytetrafluoroethylene). The first bottom wall 160 is formed of a light-transmitting and heat-resistant material such as quartz. The first lamp housing 155 is smaller than the substrate W in a plan view.

The first heat sink 156 includes a first heat sink body 161 and a first cooling mechanism 162 that supplies a cooling fluid to the first heat sink body 161 to cool the first heat sink body 161. The first heat sink body 161 is formed in a predetermined shape like a container using a metal (e.g., aluminum, iron, copper, etc.) having high heat transfer properties. The first cooling mechanism 162 includes a cooling fluid supply source 162a, a cooling fluid supply pipe 162b that supplies the cooling fluid from the supply source 162a to the first heat sink body 161, and a cooling fluid return pipe 162c that returns the cooling fluid supplied to the first heat sink body 161 to the supply source 162a. In the example of FIG. 17, the first cooling mechanism 162 supplies a cooling liquid such as cooling water as a cooling fluid to the first heat sink body 161. That is, the first heat sink 156 is a water-cooled heat sink. As the multiple first light sources 158 emit light, the first lamp 154 and its surroundings are heated. However, the first heat sink 156 cools the inside of the first lamp housing 155, so that the inside of the first lamp housing 155 can be prevented from becoming excessively hot. In the first heat sink 156, a cooling gas may be used as the cooling fluid.

As shown in FIG. 16, the processing unit 2A further includes a third arm 164 having the first lamp heater 152 attached to its tip. The first heater moving unit includes a third moving device (first heating area moving unit, first spray area moving unit) 163 that moves the third arm 164 to move the first lamp heater 152. Specifically, the third moving device 163 rotates the third arm 164 around a rotation axis A4 that extends in the vertical direction around the spin chuck 105. The third moving device 163 includes an electric motor. The third moving device 163 holds the first lamp heater 152 at a predetermined height. The third moving device 163 moves the first lamp heater 152 horizontally by rotating the third arm 164 around the rotation axis A4. The third moving device 163 may be configured to be able to move the first lamp heater 152 in the vertical direction. Specifically, the third moving device 163 may be coupled to the third arm 164 and include an arm moving unit that raises and lowers the third arm 164.

The first lamp heater 152 is used when a liquid film L of the processing liquid (a liquid film of an organic solvent) is formed on the upper surface of the substrate W and covers the upper surface of the substrate W.

As shown in FIG. 17, when the first lamp 154 emits light, that is, when the multiple first light sources 158 emit light, the light (light including at least one of near-infrared light, visible light, and ultraviolet light) emitted from the first lamp 154 passes through the first lamp housing 155 and is irradiated to the first irradiation region R1 in the upper surface of the substrate W held by the spin chuck 105. As described above, IPA is used as the organic solvent. IPA transmits almost all light with wavelengths of 200 nm to 1100 nm. Since the wavelength of the light emitted from the first lamp 154 is 200 nm to 1100 nm (more preferably, 390 nm to 800 nm), the light emitted from the first lamp 154 passes through the liquid film L without being absorbed by the liquid film L. Therefore, the light emitted from the outer surface of the first lamp housing 155 passes through the liquid film L and is irradiated to the first irradiation region R1. As a result, the first irradiation region R1 and its surrounding area (hereinafter referred to as the "first heating region RH1") on the upper surface of the substrate W (surface of the substrate W) are heated by radiation, and the temperature rises. Since a pattern 960 (see FIG. 2) is formed on the surface of the substrate W (see FIG. 2), the pattern 960 is heated by heat transfer from the surface of the substrate W, which is heating up, and the temperature rises. As the pattern 960 formed in the first heating region RH1 is heated to a predetermined heating temperature equal to or higher than the boiling point of the organic solvent, the organic solvent in contact with the first heating region RH1 is heated and evaporated.

In this state, as shown in FIG. 16, the third moving device 163 moves the first lamp heater 152 horizontally by rotating the third arm 164 around the rotation axis A4. This causes the first heating region RH1 to move within the upper surface of the substrate W.

As shown in FIG. 17, the organic solvent nozzle 133 is integrated with the first lamp heater 152. That is, the first lamp heater 152 and the organic solvent nozzle 133 are included in the top head 130. The top head 130 has a configuration in which the organic solvent nozzle 133 is integrated with the first lamp heater 152. The top head 130 has both a function as a processing liquid nozzle that ejects an organic solvent as a processing liquid and a function as a lamp heater. In addition, the top head 130 is provided with a first gas nozzle 134. The top head 130 includes a first lamp housing 155 as a housing. The organic solvent nozzle 133 is inserted vertically inside the first lamp housing 155. In addition, the first gas nozzle 134 is attached in a vertical orientation to the outer periphery 155a of the first lamp housing 155. The first heat sink 156 insulates the organic solvent nozzle 133 from the first lamp 154, so that the organic solvent flowing through the organic solvent nozzle 133 is minimally affected by the heat from the first lamp 154.

16, the first gas nozzle 134 is disposed on the tip side of the third arm 164 with respect to the first lamp heater 152. As shown in FIG. 18, the first gas outlet 134a of the first gas nozzle 134 is adjacent to the first light emitter 154A of the first lamp heater 152 when viewed from below. As shown by the two-dot chain line in FIG. 16, when the first lamp heater 152 is disposed corresponding to the outer periphery of the upper surface of the substrate W, the first gas nozzle 134 is disposed upstream of the first lamp heater 152 in the rotation direction R of the substrate W. That is, on the upper surface of the substrate W, the first blowing region RB1 (see FIG. 22E, etc.) to which the gas from the first gas nozzle 134 is blown is set upstream of the rotation direction R of the substrate W with respect to the first heating region RH1 heated by irradiation of light from the first lamp heater 152.

15, the second heating unit 171 includes a second lamp heater 172 and a second heater moving unit (the first moving device 139 described above) that moves the second lamp heater 172. As shown in FIG. 19, the second lamp heater 172 is a radiation heater that irradiates the substrate W with light including at least one of near-infrared rays, visible light, and ultraviolet rays, and heats the substrate W by radiation. The second lamp heater 172 includes a second lamp 174, a second lamp housing 175 that houses the second lamp 174, and a second heat sink 176 for cooling the inside of the second lamp housing 175. The second gas nozzle 135 is attached to the outer periphery 175a of the second lamp housing 175 in a vertical orientation.

The second lamp 174 includes a disk-shaped second lamp substrate 177 and a plurality of (six in the example of FIG. 20) second light sources 178 mounted on the underside of the second lamp substrate 177. Each second light source 178 emits light with a wavelength in the range of 200 nm to 1100 nm (light including at least one of near-infrared light, visible light, and ultraviolet light). Each second light source 178 is, for example, an LED. As shown in FIG. 20, the plurality of second light sources 178 are arranged on the underside of the second lamp substrate 177. In the example of FIG. 20, six second light sources 178 are arranged in two rows of three in the direction in which the first arm 140 extends. The arrangement density of the second light sources 178 on the second lamp substrate 177 is approximately uniform and is approximately equal to the arrangement density of the first light source 158. The second lamp board 177 is supported from below by the second bottom wall 180, which will be described next, via a connector 190. A second light-emitting section 174A having a horizontal spread is formed by a plurality of second light sources 178. The second light-emitting section 174A is smaller than the first light-emitting section 154A. The light emitted from each second light source 178 includes at least one of near-infrared light, visible light, and ultraviolet light. The wavelength of the light emitted from each second light source 178 is in the range of 200 nm to 1100 nm, and more preferably in the range of 390 nm to 800 nm.

As shown in FIG. 19, the second lamp housing 175 includes a second side wall 179 having a generally rectangular cylindrical shape and a second bottom wall 180 having a generally rectangular shape. The second side wall 179 is formed of a chemically resistant material such as PTFE (polytetrafluoroethylene). The second bottom wall 180 is formed of a light-transmitting and heat-resistant material such as quartz. The second lamp housing 175 is smaller than the substrate W in a plan view.

The second heat sink 176 includes a second heat sink body 181 and a second cooling mechanism 182 that supplies a cooling fluid to the second heat sink body 181 to cool the second heat sink body 181. The second heat sink body 181 is formed in a predetermined shape like a container using a metal (e.g., aluminum, iron, copper, etc.) having high heat transfer properties. The second cooling mechanism 182 includes a cooling fluid supply source 182a, a cooling fluid supply pipe 182b that supplies the cooling fluid from the supply source 182a to the second heat sink body 181, and a cooling fluid return pipe 182c that returns the cooling fluid supplied to the second heat sink body 181 to the supply source 182a. In the example of FIG. 19, the second cooling mechanism 182 supplies a cooling gas as a cooling fluid to the second heat sink body 181. That is, the second heat sink 176 is an air-cooled heat sink. As the second light sources 178 emit light, the second lamp 174 and its surroundings are heated. However, the second heat sink 176 cools the inside of the second lamp housing 175, so that the inside of the second lamp housing 175 can be prevented from becoming excessively hot. In the second heat sink 176, a cooling liquid such as cooling water may be used as the cooling fluid.

As shown in FIG. 16, the second lamp heater 172 is attached to the first arm 140. The second lamp heater 172 is disposed closer to the rotation axis A2 than the chemical nozzle 131. That is, the second heater moving unit that moves the second lamp heater 172 includes a first moving device (second heating area moving unit, second spraying area moving unit) 139. The first moving device 139 holds the second lamp heater 172 at a predetermined height. The first moving device 139 moves the second lamp heater 172 horizontally by rotating the first arm 140 around the rotation axis A2.

When the second lamp 174 emits light, that is, when the multiple second light sources 178 emit light, as shown in FIG. 19, the light (light including at least one of near-infrared light, visible light, and ultraviolet light) emitted from the second lamp 174 passes through the second lamp housing 175 and is irradiated to the second irradiation region R2 in the upper surface of the substrate W held by the spin chuck 105. As described above, IPA is used as the organic solvent. IPA transmits almost all light with wavelengths of 200 nm to 1100 nm. Since the wavelength of the light emitted from the second lamp 174 is 200 nm to 1100 nm (more preferably, 390 nm to 800 nm), the light emitted from the second lamp 174 passes through the liquid film L without being absorbed by the liquid film L. Therefore, the light emitted from the outer surface of the second lamp housing 175 passes through the liquid film L and is irradiated to the second irradiation region R2. As a result, the pattern 960 (see FIG. 2) formed in the second irradiation region R2 and the surrounding area (hereinafter referred to as the "second heating region RH2") on the upper surface of the substrate W is heated by radiation and rises in temperature. Since the pattern 960 is formed on the surface of the substrate W (see FIG. 2), the pattern 960 is heated by heat transfer from the surface of the substrate W, which is rising in temperature, and the temperature rises. As the pattern 960 formed in the second heating region RH2 rises in temperature to a predetermined heating temperature equal to or higher than the boiling point of the organic solvent, the organic solvent in contact with the second heating region RH2 is heated and evaporated. The second heating region RH2 is smaller than the first heating region RH1 (see FIG. 17, etc.).

In this state, as shown in FIG. 16, the first moving device 139 rotates the first arm 140 around the rotation axis A2 to move the second lamp heater 172 horizontally. As a result, the second heating region RH2 formed in a part of the upper surface of the substrate W moves within the upper surface of the substrate W.

As shown in FIG. 16, the second gas nozzle 135 is disposed on the tip side of the first arm 140 relative to the second lamp heater 172. As shown by the two-dot chain line in FIG. 16, when the second lamp heater 172 is disposed corresponding to the outer periphery of the upper surface of the substrate W, the second gas nozzle 135 is disposed upstream of the second lamp heater 172 in the rotation direction R of the substrate W. In other words, when gas is blown from the second gas nozzle 135 onto the upper surface of the substrate W, the blowing area, i.e., the second blowing area, is set upstream of the second heating area RH2 (see FIG. 22D) heated by irradiation of light from the second lamp heater 172 in the rotation direction R of the substrate W.

15, the processing cup 107 includes a plurality of guards 184 for receiving the processing liquid discharged outward from the substrate W, a plurality of cups 183 for receiving the processing liquid guided downward by the plurality of guards 184, and a cylindrical outer wall member 188 surrounding the plurality of guards 184 and the plurality of cups 183. FIG. 15 shows an example in which four guards 184 and three cups 183 are provided, and the outermost cup 183 is integrated with the third guard 184 from the top. The guard 184 includes a cylindrical portion 185 surrounding the spin chuck 105, and an annular ceiling portion 186 extending obliquely upward from the upper end of the cylindrical portion 185 toward the rotation axis A1. The plurality of ceiling portions 186 are stacked one on top of the other, and the plurality of cylindrical portions 185 are arranged in a concentric manner. The annular upper end of the ceiling portion 186 corresponds to the upper end 184u of the guard 184 surrounding the substrate W and the spin base 116 in a plan view. The multiple cups 183 are each disposed below the multiple cylindrical portions 185. The cups 183 form an annular liquid receiving groove that receives the processing liquid guided downward by the guard 184.

The processing unit 2A includes a guard lifting unit 187 that raises and lowers the multiple guards 184 individually. The guard lifting unit 187 positions the guards 184 at any position between the upper position and the lower position. Figure 15 shows two guards 184 positioned in the upper position and the remaining two guards 184 positioned in the lower position. The upper position is a position where the upper end 184u of the guard 184 is positioned above the holding position where the substrate W held by the spin chuck 105 is positioned. The lower position is a position where the upper end 184u of the guard 184 is positioned below the holding position.

When processing liquid is supplied to a rotating substrate W, at least one guard 184 is positioned in the upper position. In this state, when processing liquid is supplied to the substrate W, the processing liquid is shaken outward from the substrate W. The shaken off processing liquid collides with the inner surface of the guard 184 that faces the substrate W horizontally, and is guided to the cup 183 that corresponds to this guard 184. As a result, the processing liquid that has been expelled from the substrate W is collected in the cup 183.

The CPU 3A (FIG. 6) of the controller 3 controls each part of the processing unit 2A (FIG. 15) according to a program. Specifically, the CPU 3A controls the operation of the spin motor 119, the chuck pin drive unit 120, the first moving device 139, the second moving device 144, the third moving device 163, the guard lifting unit 187, and the like according to the program. The controller 3 also adjusts the power supplied to the first lamp heater 152, the second lamp heater 172, and the like. Furthermore, the controller 3 controls the opening and closing of the chemical liquid valve 137, the rinse liquid valve 142, the organic solvent valve 146, the first gas valve 148, and the like, and controls the actuator of the first flow rate control valve 149 to control the opening degree of the first flow rate control valve 149. The controller 3 is programmed to execute the substrate processing method described below.

<2-2. Basic Technology of Substrate Processing Method>
Next, a substrate processing method will be described in which a substrate W having a pattern 960 (FIG. 2) formed on its surface is processed by the substrate processing apparatus 1 (FIG. 1) having the above-mentioned processing unit 2A (FIG. 15). FIG. 21 is a flow diagram for explaining this substrate processing method. FIGS. 22A to 22F are schematic diagrams showing the state of the substrate W when the substrate processing method is performed. FIGS. 23A to 23D are schematic diagrams showing the substrate in the state shown in FIGS. 22B to 22E as viewed from above, respectively.

When the substrate W is processed by the processing unit 2A, a loading step (step S101 in FIG. 21) is performed to load the substrate W into the chamber 4. Specifically, with all guards 184 in the lower position and all scan nozzles in the standby position, the hand of the transport robot CR (see FIG. 1) enters the chamber 4 while supporting the substrate W. Then, the transport robot CR places the substrate W on its hand on the multiple chuck pins 117 with the surface of the substrate W facing upward. The multiple chuck pins 117 are then pressed against the outer periphery of the substrate W to grip the substrate W. After placing the substrate W on the spin chuck 105, the transport robot CR withdraws its hand from the interior of the chamber 4.

Next, the controller 3 controls the spin motor 119 to start rotating the substrate W (step S102 in FIG. 21). This causes the substrate W to rotate at the chemical supply speed (100 rpm or more and less than 1000 rpm).

Next, a chemical supply process (step S103 in FIG. 21) is performed in which a chemical liquid is supplied to the upper surface of the substrate W to form a liquid film of the chemical liquid covering the entire upper surface of the substrate W. Specifically, the controller 3 controls the first moving device 139 to move the chemical liquid nozzle 131 from the standby position to the processing position. Then, the controller 3 opens the chemical liquid valve 137 to start discharging the chemical liquid from the chemical liquid nozzle 131. When a predetermined time has elapsed since the chemical liquid valve 137 was opened, the controller 3 closes the chemical liquid valve 137. This stops the discharge of the chemical liquid from the chemical liquid nozzle 131. Then, the controller 3 controls the first moving device 139 to move the chemical liquid nozzle 131 to the standby position. The chemical liquid discharged from the chemical liquid nozzle 131 collides with the upper surface of the substrate W rotating at the chemical liquid supply speed, and then flows outward along the upper surface of the substrate W due to centrifugal force. Therefore, the chemical liquid is supplied to the entire upper surface of the substrate W, and a liquid film of the chemical liquid covering the entire upper surface of the substrate W is formed. When the chemical nozzle 131 is discharging the chemical, the controller 3 may control the first moving device 139 to move the landing position of the chemical on the top surface of the substrate W between the center and the outer periphery, or may keep the landing position stationary at the center of the top surface of the substrate W.

Next, a rinse liquid supply step (step S104 in FIG. 21) is performed in which a rinse liquid, which is an example of a rinse liquid, is supplied to the upper surface of the substrate W to wash away the chemical liquid on the substrate W. Specifically, with at least one guard 184 in the upper position, the controller 3 controls the second moving device 144 to move the rinse liquid nozzle 132 from the standby position to the processing position. The controller 3 then opens the rinse liquid valve 142 to start discharging the rinse liquid from the rinse liquid nozzle 132. Before discharging the rinse liquid starts, the controller 3 may control the guard lifting unit 187 to move at least one guard 184 vertically in order to switch the guard 184 that receives the processing liquid removed from the substrate W. When a predetermined time has elapsed since the rinse liquid valve 142 was opened, the controller 3 closes the rinse liquid valve 142 and stops discharging the rinse liquid from the rinse liquid nozzle 132. The controller 3 then controls the second moving device 144 to move the rinse liquid nozzle 132 to the standby position.

Next, an organic solvent supplying process (step S105 in FIG. 21) is performed to supply an organic solvent to the upper surface of the substrate W in order to replace the rinsing liquid on the upper surface of the substrate W with an organic solvent.

Specifically, with at least one guard 184 in the upper position, the controller 3 controls the spin chuck 105 to rotate the substrate W at a replacement speed (substrate rotation process). The replacement speed may be equal to or different from the rinse liquid supply speed. The controller 3 also controls the third moving device 163 to move the upper surface head 130 including the organic solvent nozzle 133 from the standby position to the processing position. With the organic solvent nozzle 133 positioned at the processing position, the controller 3 opens the organic solvent valve 146 to start discharging the organic solvent from the organic solvent nozzle 133. Before discharging the organic solvent starts, the controller 3 may control the guard lifting unit 187 to move at least one guard 184 vertically in order to switch the guard 184 that receives the processing liquid removed from the substrate W.

The organic solvent discharged from the organic solvent nozzle 133 collides with the upper surface of the substrate W rotating at the replacement speed, and then flows outward along the upper surface of the substrate W. The rinsing liquid on the substrate W is replaced with the organic solvent discharged from the organic solvent nozzle 133. As a result, as shown in FIG. 22A, a liquid film L of the organic solvent is formed covering the entire upper surface of the substrate W (liquid film forming process). In this substrate processing method, the organic solvent is supplied while the upper surface head 130 is stationary at a central processing position where the organic solvent discharged from the organic solvent nozzle 133 collides with the central portion of the upper surface of the substrate W. However, the controller 3 may control the third moving device 163 to move the landing position of the organic solvent on the upper surface of the substrate W between the central portion and the outer periphery.

Then, an organic solvent puddle process (step S106 in FIG. 21) is performed to hold the liquid film L on the upper surface of the substrate W. Specifically, while the upper surface head 130 is stationary at the central processing position, the controller 3 controls the spin motor 119 to reduce the rotation speed of the substrate W from the replacement speed to the paddle speed. The paddle speed is, for example, a speed greater than 0 rpm and equal to or less than 50 rpm. The deceleration from the replacement speed to the paddle speed is performed in stages. After the rotation speed of the substrate W has been reduced to the paddle speed, the controller 3 closes the organic solvent valve 146 to stop the discharge of the organic solvent.

When the rotation speed of the substrate W is reduced to the paddle speed, the centrifugal force acting on the organic solvent on the substrate W is weakened. As a result, the organic solvent is not removed from the upper surface of the substrate W, or only a small amount is removed. Therefore, even after the discharge of the organic solvent is stopped, the liquid film L covering the entire upper surface of the substrate W is retained on the substrate W. Even if a small amount of the rinsing liquid remains between the patterns 960 (see FIG. 2) after the rinsing liquid is replaced with the liquid film L, this rinsing liquid dissolves in the organic solvent that constitutes the liquid film L and diffuses into the organic solvent. This makes it possible to reduce the amount of rinsing liquid remaining between the patterns 960.

Next, after the liquid film L is formed on the upper surface of the substrate W, a vapor layer forming section forming step (step S107 in FIG. 21) is performed in which the substrate W is heated by irradiation with light from the first lamp heater 152 included in the upper surface head 130, thereby forming a vapor layer forming section VF in the center of the upper surface of the substrate W. As shown in FIG. 22B, the vapor layer forming section VF is a region where a gas film VL is formed between the organic solvent and the upper surface of the substrate W and where the liquid film L is held on the gas film VL.

Specifically, while the upper surface head 130 is stationary at the central processing position, the controller 3 starts supplying power to the first lamp heater 152 while maintaining the rotation of the substrate W at the paddle speed, and starts emitting light from the multiple first light sources 158 included in the first lamp heater 152. When the multiple first light sources 158 emit light, light is emitted from the first lamp heater 152 as shown in FIG. 22B. The light emitted from the first lamp heater 152 is not absorbed by the liquid film L, but passes through the liquid film L and is irradiated to the first irradiation region R1. As a result, the first heating region RH1 is heated by radiation. Then, the pattern 960 of the first heating region RH1 is heated by the first heating region RH1, and the pattern 960 is heated to a predetermined heating temperature equal to or higher than the boiling point of the organic solvent. As a result, the organic solvent in contact with the pattern 960 of the first heating region RH1 is heated. The first heating region RH1 is set in the center of the top surface of the substrate W, and is not set in the outer periphery of the top surface of the substrate W.

In addition, when the temperature of the first heating region RH1 (i.e., the temperature of the pattern 960 formed in the first heating region RH1) is equal to or higher than the boiling point of the organic solvent, the organic solvent evaporates at the interface between the liquid film L and the substrate W, and many small bubbles are interposed between the organic solvent and the upper surface of the substrate W. As the organic solvent evaporates at every location at the interface between the liquid film L and the substrate W, a gas film VL (see FIG. 22B) containing the vapor of the organic solvent is formed between the liquid film L and the substrate W. As a result, the organic solvent is separated from the upper surface of the substrate W, and the liquid film L floats from the upper surface of the substrate W. Then, the liquid film L is held on the gas film VL. At this time, the frictional resistance acting on the liquid film L on the substrate W is so small that it can be considered to be zero. That is, by heating the first heating region RH1 by the first lamp heater 152, a vapor layer formation portion VF is formed in the center of the upper surface of the substrate W, as shown in FIG. 23A. The vapor layer forming portion VF is a region where a gas film VL is formed between the organic solvent and the upper surface of the substrate W, and a liquid film L is held on the gas film VL.

Meanwhile, the area outside the first heating region RH1 on the upper surface of the substrate W does not reach the heating temperature. As a result, either no gas film VL is formed or the amount of gas film VL that is formed is insufficient, and the gas film VL cannot maintain the liquid film L at a sufficient height. Therefore, the steam layer formation portion VF is not formed in the area outside the first heating region RH1 on the upper surface of the substrate W. Because the substrate W is rotating, the steam layer formation portion VF is a nearly circular area that covers the center of the upper surface of the substrate W.

Since the substrate W is rotating, centrifugal force is applied to the liquid film L in the vapor layer forming section VF. In addition, a large temperature difference occurs on the upper surface of the substrate W between the first heating region RH1 and the region outside the first heating region RH1. Due to this temperature difference, thermal convection is formed on the upper surface of the substrate W, flowing from the center to the outer periphery. These centrifugal forces and thermal convection form an initial opening H in the center of the liquid film L in the vapor layer forming section VF.

Because the rotation speed of the substrate W is the paddle speed, the centrifugal force acting on the liquid film L in the vapor layer forming section VF is weak. Also, the thermal convection occurring on the upper surface of the substrate W is relatively weak. However, in the vapor layer forming section VF, the frictional resistance acting on the liquid film L on the substrate W is so small that it can be considered to be zero, so that the organic solvent contained in the liquid film L is pushed outward by the gas pressure due to these centrifugal forces and thermal convection. As a result, the thickness of the central part of the liquid film L decreases, and as shown in Figures 22C and 23B, an approximately circular initial opening H is formed in the central part of the liquid film L. The initial opening H is an exposure hole that exposes the upper surface of the substrate W. The liquid film L is partially removed by the formation of the initial opening H, so that the vapor layer forming section VF has a circular shape. Then, a gas-liquid interface GL is formed between the liquid film L in the vapor layer forming section VF and the initial opening H, i.e., on the inner circumference of the liquid film L in the vapor layer forming section VF.

Next, a hole OP (FIG. 23C) is formed by blowing gas to the initial opening H (FIGS. 22C and 23B) on the substrate W. Specifically, the controller 3 opens the first gas valve 148 (FIG. 15), and gas begins to be discharged from the first gas outlet 134a (FIG. 22C) of the first gas nozzle 134 (first blowing step). The temperature of the gas supplied to the first gas nozzle 134 may be room temperature or higher. The gas discharged from the first gas nozzle 134 collides with the liquid film L in the first blowing area RB1 set in the center of the upper surface of the substrate W, and then flows outward in all directions along the surface of the liquid film L. This forms an airflow that flows outward from the center of the upper surface of the substrate W. The flow rate of the gas supplied to the first gas nozzle 134 is, for example, 5 L/min. By blowing gas onto the first blowing region RB1, which is set inside the inner periphery of the steam layer forming part VF, the inner periphery of the steam layer forming part VF is pushed toward the outer periphery of the substrate W. This causes the initial opening part H to expand, forming a hole OP (step S108 in FIG. 21).

Next, as shown in Figures 22D and 23C, a steam layer forming part moving process (step S109 in Figure 21) is performed in which the steam layer forming part VF is moved toward the outer periphery of the substrate W. This steam layer forming part moving process (step S109 in Figure 21) includes an outer periphery expansion process in which the outer periphery of the steam layer forming part VF is expanded, and a hole expansion process in which the outer edge of the hole OP (i.e., the inner periphery of the steam layer forming part VF) is expanded. The hole expansion process is performed in parallel with the outer periphery expansion process.

Prior to the start of the vapor layer formation unit movement process (step S109 in FIG. 21), the controller 3 controls the spin motor 119 to adjust the rotation speed of the substrate W from the paddle speed to the formation unit movement speed. The formation unit movement speed is, for example, a speed greater than 0 and equal to or less than 100 rpm. The formation unit movement speed may be the same speed as the paddle speed.

In the vapor layer forming section moving step (step S109 in FIG. 21), while discharging gas from the first gas nozzle 134 and irradiating light from the first lamp heater 152, the controller 3 controls the third moving device 163 to move the upper surface head 130 including the first lamp heater 152 horizontally toward the outer periphery of the substrate W. As a result, the first heating region RH1 moves toward the outer periphery of the substrate W along a circular arc-shaped trajectory passing through the center of the substrate W in a planar view within the upper surface of the substrate W. Since the first heating region RH1 moves toward the outer periphery of the substrate W while the substrate W is rotating, the first lamp heater 152 can heat the entire inner periphery of the substrate W well. As the first heating region RH1 moves, the outer periphery of the annular vapor layer forming section VF expands (outer periphery expansion step).

In addition, since the first gas nozzle 134 is arranged to be movable together with the first lamp heater 152, the first blowing area RB1 moves while maintaining a constant distance from the first heating area RH1 (first blowing area moving process). The first blowing area RB1 moves toward the outer periphery of the substrate W in association with the movement of the first heating area RH1 toward the outer periphery of the substrate W. By moving the first blowing area RB1 toward the outer periphery of the substrate W, the outer edge of the hole OP, i.e., the inner periphery of the steam layer forming section VF, is expanded (hole expanding process). In the steam layer forming section VF, the frictional resistance acting on the liquid film L on the substrate W is so small that it can be considered to be zero, so that the small pushing force due to the gas flow can smoothly move the inner periphery of the steam layer forming section VF toward the outer periphery of the substrate W. By blowing gas into the first blowing region RB1 and moving the first blowing region RB1 toward the outer periphery of the substrate W, the inner periphery of the steam layer forming region VF can be expanded while controlling the inner periphery position of the steam layer forming region VF with high precision. The gas-liquid interface GL formed on the inner periphery of the steam layer forming region VF moves toward the outer periphery of the substrate W while maintaining its height position higher than the upper end of the pattern 960.

The first blowing area RB1 is set upstream of the first heating area RH1 in the rotation direction R (Figure 16) of the substrate W. Therefore, gas can be blown onto the inner circumference of the steam layer formation part VF while minimizing the effects of the generated airflow. This allows the inner circumference of the steam layer formation part VF to be expanded satisfactorily.

In addition, since the first gas outlet 134a is adjacent to the first light-emitting portion 154A when viewed from below, gas can be sprayed onto the inner circumference of the annular steam layer forming portion VF formed by the first heating region RH1 heated by the first light-emitting portion 154A.

In addition, the enlargement of the hole OP in the hole enlargement process is promoted not only by the blowing of gas, but also by the centrifugal force acting on the organic solvent on the upper surface of the substrate W due to the rotation of the substrate W. The liquid film L outside the vapor layer formation part VF is pushed outward by the organic solvent moving from the center side of the substrate W, and is discharged outside the substrate W.

In this substrate processing method, halfway through the vapor layer forming section moving process (step S109 in FIG. 21), the substrate W is heated not only by irradiation with light from the first lamp heater 152 but also by irradiation with light from the second lamp heater 172 (step S109 in FIG. 21). The heating of the substrate W using this second lamp heater 172 assists (assists) the heating of the substrate W by irradiation with light from the first lamp heater 152 (auxiliary heating process).

Prior to the start of light irradiation from the second lamp heater 172, the controller 3 controls the first moving device 139 to move the second lamp heater 172 from the standby position to the processing position, and position the second lamp heater 172 at a predetermined irradiation start position PS1.

When a predetermined period has elapsed since the start of irradiation of the first lamp heater 152 and the first heating region RH1 reaches a predetermined reference position RP as shown in FIG. 22D, the controller 3 starts supplying power to the second lamp heater 172 and starts emitting light from the multiple second light sources 178 included in the second lamp heater 172 (step S110 in FIG. 21). This starts heating the substrate W by the second lamp heater 172. When the multiple second light sources 178 emit light, light is emitted from the second lamp heater 172 and the light is irradiated onto the region below the second lamp heater 172. The light emitted from the second lamp heater 172 is not absorbed by the liquid film L, but passes through the liquid film L and is irradiated onto the second irradiation region R2. This causes the second heating region RH2 to be heated by radiation. Then, the pattern 960 in the second heating region RH2 is heated by the second heating region RH2, and the temperature of this pattern 960 is raised to a predetermined heating temperature that is equal to or higher than the boiling point of the organic solvent. This causes the organic solvent in contact with the pattern 960 in the second heating region RH2 to be heated.

The second heating area RH2 by the second lamp heater 172 arranged at the irradiation start position PS1 is separated from the first heating area RH1 located at the reference position RP in the rotation direction R. In addition, the distance between the inner circumferential end of the second heating area RH2 by the second lamp heater 172 arranged at the irradiation start position PS1 and the rotation axis A1 is approximately the same as the distance between the inner circumferential end of the first heating area RH1 located at the reference position RP and the rotation axis A1.

It is also preferable that the second heating region RH2 is separated from the first heating region RH1, but it may overlap partially with the first heating region RH1 as long as it does not overlap entirely with the first heating region RH1. In other words, at least a portion of the first heating region RH1 and the second heating region RH2 do not have to overlap.

Then, while heating the substrate W with the second lamp heater 172, the controller 3 controls the first moving device 139 to move the second lamp heater 172 horizontally toward the outer periphery of the substrate W. This causes the second irradiation region R2 to move along a predetermined arc-shaped trajectory within the upper surface of the substrate W toward the outer periphery of the substrate W.

At this time, the rotation speed of the first arm 140 is equal to the rotation speed of the third arm 164. Therefore, the radial movement speed of the substrate W in the second heating region RH2 is equal to the radial movement speed of the substrate W in the first heating region RH1. That is, the first heating region RH1 and the second heating region RH2 move while the distance between the inner circumferential end of the second heating region RH2 and the rotation axis A1 is kept approximately the same as the distance between the inner circumferential end of the first heating region RH1 and the rotation axis A1. Since the first heating region RH1 and the second heating region RH2 move toward the outer periphery of the substrate W while the substrate W is rotating, the first lamp heater 152 and the second lamp heater 172 can be used to scan and heat the entire upper surface of the substrate W well.

By expanding the outer periphery of the steam layer forming part VF and the outer edge of the hole OP, the liquid film L rises smoothly throughout the entire area of the steam layer forming part VF, while the steam layer forming part VF moves toward the outer periphery of the substrate W. At this time, the gas-liquid interface GL formed on the inner periphery of the steam layer forming part VF moves toward the outer periphery of the substrate W while maintaining its height position higher than the upper end of the pattern 960.

As the outer periphery of the steam layer forming part VF and the outer edge of the hole OP expand further, as shown in Figures 22E and 23D, the liquid film L outside the steam layer forming part VF is expelled from the substrate W, and only the annular steam layer forming part VF remains on the upper surface of the substrate W. Then, as shown in Figure 22F, as the first blowing area RB1 reaches the outer periphery of the substrate W, the outer edge of the hole OP (i.e. the inner periphery of the steam layer forming part VF) expands to the outer periphery of the upper surface of the substrate W, and the liquid film L of the steam layer forming part VF is expelled from the substrate W.

As a result, the liquid disappears from the top surface of the substrate W, and the entire top surface of the substrate W is exposed. After the hole OP has expanded to the entire area, no liquid droplets are present on the top surface of the substrate W. This completes the drying of the substrate W.

By moving the annular steam layer forming part VF, the liquid film L can be removed from the substrate W without the gas-liquid interface GL formed on the inner circumference of the steam layer forming part VF coming into contact with the pattern 960. This makes it possible to suppress the surface tension that the organic solvent exerts on the pattern 960 on the substrate W, thereby suppressing or preventing the collapse of the pattern 960.

When a predetermined heating period has elapsed since the start of irradiation of the first lamp heater 152, the controller 3 stops the supply of power to the first lamp heater 152 and the second lamp heater 172 to stop the emission of light from the first lamp heater 152 and the second lamp heater 172. The controller 3 also controls the spin motor 119 to stop the rotation of the substrate W (step S111 in FIG. 21).

After the rotation of the substrate W has stopped, an unloading process (step S112 in FIG. 21) is performed to unload the substrate W from the chamber 4. Specifically, the controller 3 controls the guard lifting unit 187 to lower all of the guards 184 to the lower position. The controller 3 also closes the first gas valve 148 to stop the gas being discharged from the first gas nozzle 134. The controller 3 also controls the third moving device 163 to retract the upper surface head 130 to the standby position. The controller 3 also controls the first moving device 139 to retract the second lamp heater 172 to the standby position.

Then, the hand of the transport robot CR enters the chamber 4. After the chuck pin drive unit 120 releases the grip of the substrate W by the multiple chuck pins 117, the transport robot CR supports the substrate W on the spin chuck 105 with its hand. The transport robot CR then withdraws the hand from inside the chamber 4 while still supporting the substrate W with the hand. This causes the processed substrate W to be removed from the chamber 4.

<2-3. Technology to suppress variation in substrate processing methods>
Steps S101 to S112 (FIG. 21) of the substrate processing method are repeated to process a plurality of substrates W. A technique for suppressing the variation in step S109 will be described. In this technique, similar to the technique of the first embodiment described above, a situation occurring in the substrate processing of a certain substrate is referred to in setting conditions for the substrate processing of at least one other substrate (typically a plurality of substrates), thereby suppressing process variation in the substrate processing. In the following, the above-mentioned "specific substrate" may be referred to as a reference substrate (or a first substrate W), and the above-mentioned "at least one other substrate" may be referred to as a normal substrate (or a second substrate W). Furthermore, the substrate processing of the reference substrate may be referred to as a reference substrate processing, and the above-mentioned substrate processing of the normal substrate may be referred to as a normal substrate processing. The reference substrate and the normal substrate may have a substantially common configuration. Furthermore, the reference substrate processing and the normal substrate processing may be substantially common substrate processing, except for the difference in parameter values of the processing conditions.

First, step 100j (Fig. 24) is performed in response to steps S105 to S109 (Fig. 21) for the reference substrate processing (substrate processing of substrate W as the reference substrate). The specific method is described below.

In step S101j (FIG. 24), a first liquid film L of an organic solvent is formed on the first substrate W, which is the reference substrate (see FIG. 22A). In other words, the above-described steps S105 to S106 (FIG. 21) are performed on the first substrate W.

Next, in step S102j (FIG. 24), the first substrate W is heated to form a first gas film VL that holds the first liquid film L (see FIG. 22B). In other words, the above-mentioned step S107 (FIG. 21) is performed on the first substrate W. Step S102j (FIG. 24) includes step S102jL of irradiating the first substrate W with light from a first lamp heater 152 (FIG. 22B) in order to heat the first substrate W.

Next, in step S130j (FIG. 24), centrifugal force due to the rotation of the first substrate W and thermal convection due to localized heating of the center of the first substrate W act on the first liquid film L to form an initial opening H (FIGS. 22C and 23B). Next, in step S103j (FIG. 24), an inert gas is ejected under predetermined conditions (first conditions) into the initial opening H, to form a first hole OP in the first liquid film L.

Next, in step S104j (FIG. 24), the first hole OP (FIGS. 22D and 23C) is expanded by discharging inert gas to the first substrate W as a reference substrate under a second predetermined condition different from the first condition described above. Specifically, while discharging inert gas and irradiating light from the lamp heater 152, the upper surface head 130 is moved horizontally toward the outer periphery of the substrate W under the second condition (see FIG. 22D). As a result, the heating region RH1 moves toward the outer periphery of the substrate W along a circular arc-shaped trajectory passing through the center of the substrate W in a plan view within the upper surface of the substrate W (see FIG. 23C). In addition, the inert gas spraying region moves toward the outer periphery of the substrate W in conjunction with the movement of the heating region RH1 toward the outer periphery of the substrate W. As a result, the outer periphery of the first hole OP is expanded. The expansion of the outer periphery is also promoted by the centrifugal force acting on the organic solvent on the upper surface of the substrate W due to the rotation of the substrate W.

Next, steps S105j and S111j (FIG. 24) are performed in the same manner as steps S105h and S111h (FIG. 10: embodiment 1). Note that, as in embodiment 1 described above, the image acquisition in step S105j may be performed when a predetermined time has elapsed from a reference time point. The reference time point is a specific time point in the substrate processing method, and in embodiment 2, may be the time point when scanning of the first spray area RB1 begins (in other words, the time point when scanning of the top surface head 130 begins).

In step S121j (FIG. 24), the hole OP is further enlarged following step S104j by discharging the inert gas to the first substrate W under a third predetermined condition. The third condition may include a setting condition for the flow rate of the inert gas discharged to the first substrate W. The third condition may also include a setting condition for the moving speed of the top surface head 130 from the center to the outer periphery of the first substrate W (in other words, the scanning speed of the top surface head 130). The third condition may also include a setting condition for the rotation speed of the substrate W. The third condition may also include a setting condition for the output of the lamp heater 152. Finally, the top surface head 130 is moved until it reaches the outer periphery of the substrate W, thereby removing the IPA liquid film L from the top surface S2.

This completes the drying process (step S100j (Figure 24)) for the first substrate W as the reference substrate. In other words, the reference substrate process (processing for the reference substrate) is finished.

As in the first embodiment described above, after the reference substrate processing described above, normal substrate processing (substrate processing of the second substrate W as a normal substrate) is performed. As described above, step S100j (FIG. 24) is performed on the reference substrate (first substrate W), but step S100k (FIG. 25) is performed on the normal substrate (second substrate W). Details of step S100k are described below.

First, in step S101k (FIG. 25) similar to step S101j (FIG. 24) described above, a second liquid film L of an organic solvent is formed on the second substrate W, which is a normal substrate (see FIG. 22A). Next, in step S102k (FIG. 25) similar to step S102j (FIG. 24) described above, the second substrate W is heated to form a second gas film VL that holds the second liquid film L (see FIG. 22B). Step S102k (FIG. 25) includes step S102kL of irradiating the second substrate W with light from the first lamp heater 152 (FIG. 22B) to heat the second substrate W. Next, in step S130k (FIG. 25) similar to step S130j (FIG. 24) described above, an initial opening H is formed in the second liquid film L. Next, a second hole OP (FIGS. 22D and 23C) is formed in the second liquid film L by step S103k (FIG. 25), which is similar to step S103j (FIG. 24) described above. Next, the first hole OP is enlarged by step S104k (FIG. 25), which is similar to step S104j (FIG. 24) described above. Next, a second image is acquired by step S105k (FIG. 25), which is similar to step S105j (FIG. 24) described above. Next, step S111k (FIG. 25) is performed in the same manner as step S111i (FIG. 11: embodiment 1).

Next, in step S112k (FIG. 25), a third condition for discharging inert gas onto the upper surface of the second substrate W is adjusted based on the progress of the expansion of the second hole OP evaluated as described above. This adjustment may be performed by a condition adjustment unit (not shown) configured by the controller 3. Next, in step S121k (FIG. 25), the second hole OP is further expanded by discharging inert gas onto the upper surface of the second substrate W under the third condition adjusted as described above.

If the second hole OP is determined to be excessively large as a result of the comparison in step S111k (FIG. 25) above, the third condition is adjusted so as to suppress the expansion of the second hole OP. For example, the flow rate of the inert gas sprayed onto the second substrate W is adjusted to be smaller. This adjustment amount may be a predetermined amount, or may be an amount calculated from the results of the comparison above. Conversely, if the second hole OP is determined to be too small, the third condition is adjusted so as to promote the expansion of the second hole OP. For example, the flow rate of the inert gas is adjusted to be larger.

<2-4. Effects>
According to the second embodiment, the progress of the expansion of the second hole OP caused by discharging the inert gas to the upper surface S2 of the normal substrate under the predetermined condition (second condition) is evaluated based on the progress of the expansion of the first hole OP caused by discharging the inert gas to the upper surface of the reference substrate under the predetermined condition (second condition). By adjusting the third condition (for example, the flow rate of the inert gas) based on this progress, the progress speed of the further expansion of the second hole OP of the normal substrate can be made closer to the standard progress speed. This makes it possible to suppress the variation in the progress speed of the expansion of the second hole OP of the liquid film L on the upper surface of the normal substrate. Therefore, it is possible to suppress the adverse effect on the upper surface of the normal substrate caused by the variation. Specifically, it is possible to suppress the collapse of the pattern 960 provided on the upper surface of the normal substrate.

<2-5. Modified Examples>
22E , gas may be blown toward the inside of the inner circumference of the steam layer forming portion VF not only from the first gas nozzle 134 but also from the second gas nozzle 135. In this case, the third condition may be a condition related not only to the blowing from the first gas nozzle 134 but also to the blowing from the second gas nozzle 135.

<3. Third embodiment>
The substrate processing method according to the third embodiment can be carried out using the same processing unit 2A as that used in the above-described second embodiment. However, in the third embodiment, the inert gas discharge mechanism (specifically, the first gas nozzle 134, the first gas pipe 147, the first gas valve 148, the first flow rate control valve 149, the second gas nozzle 135, the second gas pipe 197, the second gas valve 198, and the second flow rate control valve 199) may be omitted.

In this embodiment, unlike the second embodiment described above, steps S108 to S110 (FIG. 21) are performed without using the ejection of an inert gas. Correspondingly, in the third embodiment, steps S100m and S100n (FIGS. 26 and 27) are performed instead of steps S100j and S100k (FIGS. 24 and 25), respectively, in the second embodiment described above.

In step S100m (FIG. 26), first, steps S101j and S102j are performed in the same manner as in embodiment 2. After step S102j, the light irradiation is continued to form the initial opening H described in embodiment 2 as the first hole OP in embodiment 3 (step S103m). In other words, in embodiment 3, the formation of the initial opening H described in embodiment 2 above is regarded as the formation of a hole OP. Next, steps S104m, S105m, S111m, and S121m are each performed in the same manner as steps S104j, S105j, S111j, and S121j (FIG. 24) in embodiment 2, except that in this embodiment, no inert gas is discharged.

Similarly, in step S100n (FIG. 27), first, steps S101k and S102k are performed in the same manner as in embodiment 2. After step S102k, the initial opening H described in embodiment 2 is formed as the second hole OP in embodiment 3 by continuing the irradiation of light (step S103n). In other words, in embodiment 3, the formation of the initial opening H described in embodiment 2 above is regarded as the formation of a hole OP. Then, steps S104n, S105n, S111n, S112n, and S121n are each performed in the same manner as steps S104k, S105k, S111k, S112k, and S121k in embodiment 2 (FIG. 25), except that in this embodiment, no inert gas is discharged.

In the third embodiment, the third condition for adjusting the progress of the expansion of the hole OP may include a setting condition for the intensity of the light irradiated from the first lamp heater 152 to the substrate W. The third condition may also include a setting condition for the moving speed of the first lamp heater 152 from the center to the outer periphery of the substrate W (in other words, the scanning speed of the first lamp heater 152). The third condition may also include a setting condition for the rotation speed of the substrate W.

<4. Fourth embodiment>
<4-1. Configuration of the substrate processing apparatus>
In the fourth embodiment, the substrate processing apparatus 1 (FIG. 1) is provided with a processing unit 2B (FIGS. 28 and 29) instead of the processing unit 2 (FIG. 1). FIGS. 28 and 29 are a plan view and a cross-sectional view, respectively, that show a schematic configuration of the processing unit 2B. As shown in FIGS. 28 and 29, the processing unit 2B includes a chamber 4, a substrate holding part 1020, a rotating mechanism 1030, a fluid supply part 1040, a processing liquid collecting part 1050, a heating part 1060, an imaging part IM, and a controller 3.

The chamber 4 is a housing containing a processing space 1011 for processing the substrate W. The chamber 4 has a side wall 1012 surrounding the side of the processing space 1011, a top plate part 1013 covering the upper part of the processing space 1011, and a bottom plate part 1014 covering the lower part of the processing space 1011. The substrate holding part 1020, the rotating mechanism 1030, the fluid supply part 1040, the processing liquid collecting part 1050, the heating part 1060, and the imaging part IM are housed inside the chamber 4. A part of the side wall 1012 is provided with a loading/unloading port for loading the substrate W into the chamber 4 and unloading the substrate W from the chamber 4, and a shutter for opening and closing the loading/unloading port (all not shown). As shown in FIG. 29, a fan filter unit (FFU) 1015 is provided on the top plate part 1013 of the chamber 4. The fan filter unit 1015 has a dust collection filter such as a HEPA filter and a fan that generates an airflow. When the fan filter unit 1015 is operated, air in a clean room in which the substrate processing apparatus 1 (FIG. 1) is installed is taken into the fan filter unit 1015, purified by the dust collection filter, and supplied to the processing space 1011 in the chamber 4. This creates a downflow of clean air in the processing space 1011 in the chamber 4. An exhaust duct 1016 is connected to a part of the lower part of the side wall 1012. The air supplied from the fan filter unit 1015 forms a downflow inside the chamber 4, and then is exhausted to the outside of the chamber 4 through the exhaust duct 1016.

The substrate holding unit 1020 is a mechanism that holds the substrate W horizontally (in a position in which the normal line faces the vertical direction) inside the chamber 4. As shown in FIG. 2 and FIG. 29, the substrate holding unit 1020 has a disk-shaped spin base 1021 and a plurality of chuck pins 1022. The plurality of chuck pins 1022 are provided at equal angular intervals along the outer periphery of the upper surface of the spin base 1021. The substrate W is held by the plurality of chuck pins 1022 with the processing surface on which the pattern is formed facing upward. Each chuck pin 1022 contacts the lower surface and the outer periphery end surface of the peripheral portion of the substrate W, and supports the substrate W at a position above the upper surface of the spin base 1021 through a gap. Inside the spin base 1021, a chuck pin switching mechanism 1023 for switching the positions of the plurality of chuck pins 1022 is provided. The chuck pin switching mechanism 1023 switches the multiple chuck pins 1022 between a holding position that holds the substrate W and a release position that releases the substrate W.

The rotation mechanism 1030 is a mechanism for rotating the substrate holding part 1020. The rotation mechanism 1030 is housed inside a motor cover 1031 provided below the spin base 1021. As shown by the dashed line in FIG. 29, the rotation mechanism 1030 has a spin motor 1032 and a support shaft 1033. The support shaft 1033 extends vertically, with its lower end connected to the spin motor 1032 and its upper end fixed to the center of the lower surface of the spin base 1021. When the spin motor 1032 is driven, the support shaft 1033 rotates around its axis 1330. Then, together with the support shaft 1033, the substrate holding part 1020 and the substrate W held by the substrate holding part 1020 also rotate around the axis 1330.

The processing liquid collecting section 1050 is a section for collecting the processing liquid after use. As shown in FIG. 29, the processing liquid collecting section 1050 has an inner cup 1051, a middle cup 1052, and an outer cup 1053. The inner cup 1051, the middle cup 1052, and the outer cup 1053 can be moved up and down independently of each other by a lifting mechanism not shown. The inner cup 1051 has a first guide plate 1510 in an annular shape surrounding the periphery of the substrate holding section 1020. The middle cup 1052 has a second guide plate 1520 in an annular shape located outside and above the first guide plate 1510. The outer cup 1053 has a third guide plate 1530 in an annular shape located outside and above the second guide plate 1520. In addition, the bottom of the inner cup 1051 extends to below the middle cup 1052 and the outer cup 1053. The upper surface of the bottom is provided with a first drain groove 1511, a second drain groove 1512, and a third drain groove 1513 in this order from the inside. The processing liquid supplied to the upper surface of the substrate W from the fluid supply unit 1040 is scattered to the outside by centrifugal force caused by the rotation of the substrate W or by the blowing of nitrogen gas in the drying process described later. The processing liquid scattered from the substrate W is collected on the inside of any of the first guide plate 1510, the second guide plate 1520, and the third guide plate 1530. The processing liquid collected on the inside of the first guide plate 1510 is discharged to the outside of the processing unit 2B through the first drain groove 1511. The processing liquid collected on the inside of the second guide plate 1520 is discharged to the outside of the processing unit 2B through the second drain groove 1512. The processing liquid collected on the inside of the third guide plate 1530 is discharged to the outside of the processing unit 2B through the third drainage groove 1513. In this way, the processing unit 2B has multiple discharge paths for the processing liquid. Therefore, the processing liquid supplied to the substrate can be separated and collected by type. Therefore, the disposal and regeneration of the collected processing liquid can be performed separately according to the properties of each processing liquid.

The heating section 1060 is a heating means for heating the substrate W in the drying process described later. The heating section 1060 in this embodiment has a disk-shaped hot plate 1061 and a heater 1062 serving as a heat source. The hot plate 1061 is disposed between the upper surface of the spin base 1021 and the lower surface of the substrate W held by the chuck pins 1022. The heater 1062 is embedded inside the hot plate 1061. For example, an electric heating wire such as a nichrome wire that generates heat when electricity is applied is used for the heater 1062. When electricity is applied to the heater 1062, the hot plate 1061 is heated to a temperature higher than the ambient temperature. The processing unit 2B further includes a lifting mechanism (not shown) for lifting and lowering the hot plate 1061. This allows the hot plate 1061 to be disposed in an upper position and a lower position. The hot plate 1061 in the upper position heats the substrate W by contacting the lower surface of the substrate W. The hot plate 1061 in the lower position is far enough below the substrate W to avoid the substrate W from being substantially heated.

The fluid supply unit 1040 is a mechanism for supplying a processing liquid and an inert gas to the upper surface of the substrate W held by the substrate holding unit 1020. As shown in FIG. 2 and FIG. 29, the fluid supply unit 1040 has a first nozzle 1041, a second nozzle 1042, and a third nozzle 1043. The first nozzle 1041 has a first nozzle arm 1411, a first nozzle head 1412 provided at the tip of the first nozzle arm 1411, and a first nozzle motor 1413. The second nozzle 1042 has a second nozzle arm 1421, a second nozzle head 1422 provided at the tip of the second nozzle arm 1421, and a second nozzle motor 1423. The third nozzle 1043 has a third nozzle arm 1431, a third nozzle head 1432 provided at the tip of the third nozzle arm 1431, and a third nozzle motor 1433. Each nozzle arm 1411, 1421, 1431 is rotated individually in the horizontal direction around the base end of each nozzle arm 1411, 1421, 1431 as indicated by the arrow in FIG. 2 by the drive of the nozzle motors 1413, 1423, 1433. This allows each nozzle head 1412, 1422, 1432 to be moved between a processing position above the substrate W held by the substrate holder 1020 and a retracted position outside the processing liquid collector 1050.

Figure 30 is a diagram showing an example of a liquid supply unit connected to the first nozzle head 1412. In the example of Figure 30, the first nozzle head 1412 is connected to a chemical liquid supply source 1415 via a chemical liquid piping 1414. A chemical liquid valve 1416 is inserted in the middle of the path of the chemical liquid piping 1414. Therefore, when the first nozzle head 1412 is placed at the processing position and the chemical liquid valve 1416 is opened, the chemical liquid is supplied from the chemical liquid supply source 1415 through the chemical liquid piping 1414 to the first nozzle head 1412. The chemical liquid is then ejected from the first nozzle head 1412 toward the top surface of the substrate W. Examples of chemical liquids that can be ejected from the first nozzle head 1412 include SPM cleaning liquid (a mixture of sulfuric acid and hydrogen peroxide), SC1 cleaning liquid (a mixture of ammonia water, hydrogen peroxide, and pure water), SC2 cleaning liquid (a mixture of hydrochloric acid, hydrogen peroxide, and pure water), and DHF cleaning liquid (dilute hydrofluoric acid).

Figure 31 is a diagram showing an example of a liquid supply unit connected to the second nozzle head 1422. In the example of Figure 31, the second nozzle head 1422 is connected to a pure water supply source 1425 via a pure water pipe 1424. A pure water valve 1426 is inserted in the middle of the path of the pure water pipe 1424. Therefore, when the pure water valve 1426 is opened with the second nozzle head 1422 placed at the processing position, pure water (deionized water) is supplied from the pure water supply source 1425 through the pure water pipe 1424 to the second nozzle head 1422. Then, the pure water is ejected from the second nozzle head 1422 toward the upper surface of the substrate W.

Figure 32 shows an example of a liquid supply section and an air supply section connected to the third nozzle head 1432. In the example of Figure 32, the third nozzle head 1432 has an IPA outlet 1432a, a vertical outlet 1432b, and an inclined outlet 1432c.

The IPA outlet 1432a is connected to an IPA supply source 1435a via an IPA pipe 1434a. An IPA valve 1436a is inserted in the middle of the IPA pipe 1434a. Therefore, when the IPA valve 1436a is opened with the third nozzle head 1432 placed at the processing position, IPA (isopropyl alcohol), an organic solvent, is supplied from the IPA supply source 1435a through the IPA pipe 1434a to the third nozzle head 1432. Then, IPA is ejected from the IPA outlet 1432a of the third nozzle head 1432 toward the top surface of the substrate W.

The vertical blowing port 1432b is connected to the first nitrogen gas supply source 1435b via the first nitrogen gas pipe 1434b. A vertical blowing valve 1436b is inserted in the middle of the first nitrogen gas pipe 1434b. Therefore, when the third nozzle head 1432 is placed in the processing position and the vertical blowing valve 1436b is opened, nitrogen gas, which is an inert gas, is supplied from the first nitrogen gas supply source 1435b through the first nitrogen gas pipe 1434b to the third nozzle head 1432. Then, the nitrogen gas is blown downward from the vertical blowing port 1432b of the third nozzle head 1432 toward the upper surface of the substrate W.

The inclined blowing port 1432c is connected to the second nitrogen gas supply source 1435c via the second nitrogen gas pipe 1434c. An inclined blowing valve 1436c is inserted in the middle of the path of the second nitrogen gas pipe 1434c. Therefore, when the inclined blowing valve 1436c is opened with the third nozzle head 1432 placed in the processing position, nitrogen gas, which is an inert gas, is supplied from the second nitrogen gas supply source 1435c through the second nitrogen gas pipe 1434c to the third nozzle head 1432. Then, the nitrogen gas is blown outward and obliquely downward from the inclined blowing port 1432c of the third nozzle head 1432 toward the upper surface of the substrate W.

However, each of the nozzles 1041 to 1043 may be capable of switching between and ejecting multiple types of processing liquid. Furthermore, the number of nozzles provided in the processing unit 2B is not limited to three, and may be one, two, or four or more.

<4-2. Substrate processing method>
The substrate processing method of this embodiment will be described below. In this method, the substrate processing shown in FIG. 33 is repeated. At that time, similar to the above-mentioned first to third embodiments, the situation occurring in the substrate processing of a certain substrate is referred to in setting the conditions for the substrate processing of at least one other substrate, thereby suppressing the process variation of the substrate processing. In the following, the above-mentioned "specific substrate" may be referred to as the reference substrate (or the first substrate W), and the above-mentioned "at least one other substrate" may be referred to as the normal substrate (or the second substrate W). Furthermore, the substrate processing of the reference substrate may be referred to as the reference substrate processing, and the above-mentioned substrate processing of the normal substrate may be referred to as the normal substrate processing. Note that the reference substrate and the normal substrate may have an almost common configuration. Furthermore, the reference substrate processing and the normal substrate processing may be almost common substrate processing except for the difference in the parameter values of the processing conditions.

First, the reference substrate processing (substrate processing of substrate W as a reference substrate) will be described below with reference to Figure 33.

To perform the substrate processing shown in FIG. 33, a substrate loading step (step S10) is performed in which an unprocessed substrate W is loaded into chamber 4 (FIG. 29). The substrate W loaded into chamber 4 is held horizontally by multiple chuck pins 1022 of substrate holder 1020. The spin motor 1032 of rotation mechanism 1030 is then driven to start rotation of substrate W (step S20). Specifically, support shaft 1033, spin base 1021, multiple chuck pins 1022, and substrate W held by chuck pin 1022 rotate around axis 1330 of support shaft 1033.

Then, the upper surface of the substrate W is treated with a chemical solution (step S30). Specifically, first, the first nozzle head 1412 is moved to a treatment position facing the upper surface of the substrate W by driving the first nozzle motor 1413. Then, the chemical solution valve 1416 is opened. Then, the chemical solution is discharged from the first nozzle head 1412 toward the center of the upper surface of the rotating substrate W. The discharged chemical solution spreads over the entire upper surface of the substrate W by the centrifugal force caused by the rotation of the substrate W. This allows chemical solution treatment such as etching and cleaning to be performed on the upper surface of the substrate W. When the discharge of the chemical solution for a predetermined time is completed, the chemical solution valve 1416 is closed to stop the discharge of the chemical solution from the first nozzle head 1412. Then, the first nozzle motor 1413 is driven to move the first nozzle head 1412 from the treatment position to the retreat position.

Next, the top surface of the substrate W is rinsed with pure water (step S40). Specifically, first, the second nozzle head 1422 is moved to a processing position facing the top surface of the substrate W by driving the second nozzle motor 1423. Then, the pure water valve 1426 is opened. Then, pure water is discharged from the second nozzle head 1422 toward the center of the top surface of the rotating substrate W. The discharged pure water spreads over the entire top surface of the substrate W due to the centrifugal force caused by the rotation of the substrate W. This washes away the chemical solution remaining on the surface of the substrate W. When the discharge of the pure water for a predetermined time is completed, the pure water valve 1426 is closed to stop the discharge of the pure water from the second nozzle head 1422. Then, the second nozzle motor 1423 is driven to move the second nozzle head 1422 from the processing position to the retreat position.

Next, in step S100 (Figure 33), a drying process is performed. Specifically, the rinsing liquid remaining on the upper surface of the substrate W is replaced with liquid IPA, and then this IPA is dried. As this step S100, specifically, step S100a shown in Figure 34 is performed on the reference substrate (first substrate W) described above. Details of this step S100a are described below.

When performing the drying process, first, the third nozzle head 1432 (FIG. 2) is moved to a processing position facing the upper surface of the substrate W by driving the third nozzle motor 1433 (FIG. 2). Then, the IPA valve 1436a (FIG. 32) is opened. Then, IPA is ejected from the IPA ejection port 1432a of the third nozzle head 1432 toward the center of the upper surface of the rotating substrate W. The ejected IPA spreads over the entire upper surface of the substrate W due to the centrifugal force caused by the rotation of the substrate W. IPA is a liquid with a lower surface tension than pure water. Therefore, when IPA is supplied to the upper surface of the substrate W, the pure water remaining on the upper surface of the substrate W is replaced with IPA.

After that, the spin motor 1032 (FIG. 29) of the rotation mechanism 1030 is stopped to stop the rotation of the substrate W. Then, the IPA valve 1436a is closed to stop the discharge of IPA from the third nozzle head 1432. Then, as shown in FIG. 35, a liquid film L of IPA is formed in a paddle shape on the upper surface of the substrate W (step S101a (FIG. 34). At this time, the hot plate 1061 is in the lower position, and therefore heat from the hot plate 1061 is not substantially transmitted to the substrate W. Therefore, the temperature of the upper surface S2 of the substrate W remains at approximately room temperature, and therefore the IPA also covers the upper surface S2 of the substrate W while maintaining approximately room temperature. As a result, a liquid film L of liquid IPA (first liquid film L on the reference substrate) is formed on the upper surface S2 of the substrate W). As a result, as shown in FIG. 36, DIW (rinsing liquid) is replaced with liquid IPA (organic solvent) in the recesses 962 of the pattern 960 provided on the upper surface S2 of the substrate W.

As shown in FIG. 37, next, the hot plate 1061 is raised from the lower position (position shown in FIG. 36) to the upper position (position shown in FIG. 37) by controlling the lifting mechanism. As a result, heat from the hot plate 1061 is applied to the lower surface of the substrate W, and as a result, the substrate W is heated. Accordingly, the liquid film L of IPA on the upper surface of the substrate W is heated. It is preferable that the amount of heat per unit area applied to the substrate W from the hot plate 1061 is almost uniform over the entire substrate W. By heating the substrate W by the hot plate 1061, the temperature of the upper surface of the substrate W is raised to a predetermined liquid film floating temperature (predetermined temperature) that is about 40° C. to 120° C. higher than the boiling point of IPA (82.4° C.) and is maintained. In other words, the heat generation amount per unit time of the heater 1062 is set so that the upper surface of the substrate W becomes the liquid film floating temperature. A while after the temperature of the upper surface reaches the liquid film floating temperature, a part of the liquid film L of IPA on the upper surface evaporates and becomes gas phase. As a result, as shown in Figure 38, a gas film VL (first gas film) is formed on the upper surface S2 of the first substrate W as the reference substrate (step S102a (Figure 34)). The gas film VL (first gas film) holds the first liquid film L. By at least partially filling the recesses 962 (Figure 38) of the fine pattern 960 with the gas film VL, the surface tension acting between the recesses 962 is reduced, and as a result, the collapse of the structures 961 of the fine pattern 960 due to the surface tension can be suppressed or prevented.

Next, in step S103a (FIG. 34), nitrogen gas (inert gas) is discharged onto the upper surface S2 of the first substrate W. Specifically, first, the vertical blowing valve 1436b (FIG. 32) is opened. Then, nitrogen gas is blown from the vertical blowing port 1432b of the third nozzle head 1432 toward the center of the upper surface of the substrate W. This causes the center of the liquid film L to open, as shown in FIG. 39. That is, a dry region DR from which IPA has been removed is initially formed at the center of the upper surface of the substrate W. Next, the inclined blowing valve 1436c (FIG. 32) is opened. Then, nitrogen gas is blown outward and obliquely downward from the inclined blowing port 1432c of the third nozzle head 1432 toward the upper surface of the substrate W. This causes the dry region DR that was initially formed as described above to gradually expand, as shown in FIG. 40. As a result, as shown in FIG. 41, a first hole OP is formed in the first liquid film L held in the gas film VL (first gas film). The nitrogen gas is discharged to form the hole OP under predetermined conditions (first conditions). These conditions include a setting condition for the flow rate of the discharged nitrogen gas. The larger the flow rate, the larger the hole OP, but if a large flow rate is used from the beginning, abnormal shapes such as cracks are likely to occur in the liquid film L. Therefore, at the time of the above step S103a, a flow rate condition that is small enough to avoid frequent occurrence of such abnormalities is used.

12, in step S104a (FIG. 34), the first hole OP is expanded as shown by the arrow in the figure by discharging the inert gas to the reference substrate (first substrate W) under a second predetermined condition different from the first condition described above. The second condition includes a setting condition for the flow rate of the inert gas discharged to the upper surface S2 of the substrate W, and the flow rate under this setting condition is greater than the flow rate set under the first condition. In other words, in step S104a, nitrogen gas is discharged at a greater flow rate than in step S103a. The hole OP thus expanded is photographed by the camera CM (FIG. 29), and a hole image OQ (first image) is acquired (step S105a (FIG. 34)). Then, the hole image OQ is stored by the controller 3 as a reference image (step S111a (FIG. 34)).

Next, the hole OP is further enlarged by discharging inert gas onto the upper surface S2 of the substrate W under a third predetermined condition (step S121a (FIG. 34)). The third condition includes a setting condition for the flow rate of the inert gas discharged onto the upper surface S2 of the substrate W, and the flow rate under this setting condition is greater than the flow rate set under the second condition. In other words, in step S121a, nitrogen gas is discharged at a greater flow rate than in step S104a. Then, the discharge of nitrogen gas is continued until the IPA liquid film L is finally removed from the upper surface S2.

When the IPA is removed from the upper surface S2 of the substrate W, the vertical blowing valve 1436b and the inclined blowing valve 1436c (FIG. 32) are closed. This stops the blowing of nitrogen gas from the third nozzle head 1432. Thereafter, the third nozzle head 1432 is moved from the processing position to the retreat position by driving the third nozzle motor 1433. Next, the hot plate 1061 is lowered from the upper position (position in FIG. 37) to the lower position (position in FIG. 35) by controlling the lifting mechanism. This sufficiently increases the gap between the hot plate 1061 and the substrate W held by the substrate holder 1020 (FIG. 29), making it difficult for heat from the hot plate 1061 to reach the substrate W. This essentially ends the heating of the substrate W by the hot plate 1061, and the temperature of the substrate W drops to approximately room temperature. Next, the substrate W is rotated to perform spin drying of the substrate W. This removes IPA adhering to the lower surface S1 or sides of the substrate W.

This completes the drying process (step S100 (Figure 33)) for the reference substrate (first substrate W). In other words, the reference substrate process (processing of the reference substrate) is finished. Then, in step S60 (Figure 33), the substrate W is removed.

After the above-mentioned reference substrate processing, normal substrate processing (substrate processing on a substrate W as a normal substrate) is performed. Typically, after one reference substrate processing is performed once, the normal substrate processing is repeated multiple times to process a large number of normal substrates. In each normal substrate processing, first, up to step S40 (FIG. 33) is performed in the same manner as in the above-mentioned reference substrate processing. Next, in step S100 (FIG. 33), a drying process is performed. In this step S100, step S100a (FIG. 34) is performed on the above-mentioned reference substrate (first substrate W), but step S100b (FIG. 42) is performed on the normal substrate. Details of this step S100b are described below.

First, step S101b (FIG. 42) is performed in the same manner as step S101a (FIG. 34) described above. As a result, a second liquid film L of IPA (organic solvent) is formed on the second substrate W having an upper surface S2 on which the pattern 960 (FIG. 36) is provided. Next, step S102b (FIG. 42) is performed in the same manner as step S102a (FIG. 34) described above. As a result, the second substrate W is heated, and as shown in FIG. 38, a gas film VL (second gas film) that holds the second liquid film L is formed on the upper surface S2 of the substrate W. Next, step S103b (FIG. 42) is performed in the same manner as step S103a (FIG. 34) described above. Specifically, by discharging nitrogen gas (inert gas) onto the upper surface S2 of the substrate W under the first condition described above, a second hole OP is formed in the liquid film L held by the gas film VL, as shown in FIG. 41. Next, step S104b (FIG. 42) is performed in the same manner as step S104a (FIG. 34) described above. Specifically, nitrogen gas (inert gas) is discharged onto the upper surface S2 of the substrate W under the second condition described above, thereby expanding the hole OP as shown by the arrow in FIG. 12.

As shown in FIG. 43, next, in step S105b (FIG. 42), the hole OP (FIG. 43) expanded by the above step S104b (FIG. 42) is photographed by the camera CM (FIG. 29). As a result, an image (second image) of the expanded hole OP (FIG. 43) is acquired. Next, in step S111b, the hole (first hole) in the hole image OQ (first image) as the reference image is compared with the second hole OP in the above second image. As a result, the progress of the expansion of the second hole OP is evaluated. Although steps S104a and S104b are both processes set to the second condition, in reality, due to the influence of process fluctuations, a difference occurs between the first hole OP by step S104a and the hole OP by step S104b. The comparison in step S111b may be performed by an image comparison unit (not shown) configured by the controller 3.

Next, in step S112b (FIG. 42), a third condition for discharging nitrogen gas (inert gas) onto the upper surface S2 of the second substrate W is adjusted based on the progress of the expansion of the hole OP evaluated as described above. This adjustment may be performed by a condition adjustment unit (not shown) configured by the controller 3.

In the above comparison, for example, as shown in FIG. 43, the area AQ (a dotted area in FIG. 43) of the hole (first hole) in the hole image OQ (first image) may be compared with the area AP (a hatched area in FIG. 43) of the second hole OP in the second image (FIG. 43). In the example shown in FIG. 43, each of the areas AQ and AP is calculated not for the entire upper surface S2 of the substrate W, but for a partial range RE thereof. When the area AP is larger than the area AQ, the third condition is adjusted so that the expansion of the hole OP is suppressed. Specifically, the flow rate of the nitrogen gas is adjusted to be smaller. This adjustment amount may be a predetermined amount, or may be an amount corresponding to the difference between the area AQ and the area AP. Conversely, when the area AP is smaller than the area AQ, the third condition is adjusted so that the expansion of the hole OP is promoted. Specifically, the flow rate of the nitrogen gas is adjusted to be larger. This adjustment amount may be a predetermined amount, or may be an amount corresponding to the difference between area AQ and area AP.

As a modified example of the above comparison method (FIG. 43), for example, as shown in FIG. 44, the dimension (dimension from reference point P1 to end point PQ) of the hole (first hole) in the hole image OQ (first image) may be compared with the dimension (dimension from reference point P1 to end point PP) of the second hole OP in the second image (FIG. 43). In the example shown in FIG. 44, each dimension is calculated in the detection section LD extending outward from the reference point P1. If the dimension (dimension from reference point P1 to end point PP) of the hole OP is larger than the dimension (dimension from reference point P1 to end point PQ) of the hole image OQ, the third condition is adjusted so that the expansion of the hole OP is suppressed. Specifically, the flow rate of the nitrogen gas is adjusted to be smaller. Conversely, if the dimension of the hole OP (the dimension from the reference point P1 to the end point PP) is smaller than the dimension of the hole image OQ (the dimension from the reference point P1 to the end point PQ), the third condition is adjusted to promote the expansion of the hole OP. Specifically, the flow rate of the nitrogen gas is adjusted to be larger. The amount of adjustment may be a predetermined amount, or may be an amount corresponding to the magnitude of the difference in dimensions described above.

Next, in step S112b (FIG. 42), the hole OP is further enlarged by ejecting inert gas onto the upper surface S2 of the substrate W under the third condition adjusted as described above (step S121b (FIG. 42)). The adjusted third condition, like the original third condition, includes a flow rate condition greater than the flow rate condition set by the second condition described above. In other words, in step S121b, nitrogen gas is ejected at a greater flow rate than in step S104b. The ejection of nitrogen gas is continued until the IPA liquid film L is finally removed from the upper surface S2.

Next, spin drying is performed using the method described above. This removes the IPA adhering to the lower surface S1 or sides of the substrate W.

This completes the drying process (step S100 (Figure 33)) for the normal substrate (second substrate W). Then, in step S60 (Figure 33), the substrate W is removed. This completes the substrate processing method shown in Figure 33.

<4-3. Effects>
According to this embodiment, the progress of the expansion of the second hole OP caused by discharging the inert gas to the upper surface S2 of the normal substrate under the predetermined condition (second condition) is evaluated based on the progress of the expansion of the first hole OP caused by discharging the inert gas to the upper surface S2 of the reference substrate under the predetermined condition (second condition). By adjusting the condition (third condition) for further discharging the inert gas to the upper surface S2 of the normal substrate based on this progress, the progress speed of the further expansion of the second hole OP of the normal substrate can be made closer to the standard progress speed. This makes it possible to suppress the variation in the progress speed of the expansion of the second hole OP of the liquid film L on the upper surface S2 of the normal substrate. Therefore, it is possible to suppress the adverse effect on the upper surface S2 of the normal substrate caused by the variation. Specifically, it is possible to suppress the collapse of the structure 961 of the pattern 960 provided on the upper surface S2 of the normal substrate.

The third condition includes a setting condition for the flow rate of the inert gas discharged onto the upper surface S2 of the normal substrate. This makes it possible to effectively adjust the rate at which the hole OP on the normal substrate further expands.

As described above, the comparison of the first hole OP of the reference board to the second hole OP of the normal board to evaluate the progress may be performed by comparing the area AQ of the hole image OQ of the reference board to the area AP of the hole OP of the normal board, as shown in FIG. 43. In this case, it is possible to average out the effects of expansion in various directions and perform an evaluation. Alternatively, the comparison of the first hole OP of the reference board to the second hole OP of the normal board to evaluate the progress may be performed by comparing the dimensions of the hole image OQ of the reference board to the hole OP of the normal board, as shown in FIG. 44. In this case, evaluation can be performed in a simple manner.

<4-4. Modified Examples>
In the above, the third condition applied to the substrate processing of the normal substrate is adjusted based on an image of the substrate processing of the reference substrate under the third condition. As a modified example, after the above adjustment, the fourth condition applied to the substrate processing of the normal substrate may be adjusted based on an image of the substrate processing of the reference substrate under a predetermined fourth condition. In this case, two adjustments are performed for each normal substrate. As a further modified example, three or more adjustments may be performed. These multiple adjustments may be performed at predetermined intervals, for example. By increasing the number of adjustments, the variation in the progress speed of the expansion of the hole OP can be further suppressed. This modified example may be applied to other embodiments, not limited to the fourth embodiment.

Also, a configuration has been described in which the hot plate 1061 comes into contact with the substrate W when the hot plate 1061 heats the substrate W, in other words, when the hot plate is in the upper position. As a modified example, a clearance may be provided between the hot plate 1061 and the lower surface of the substrate W when the hot plate 1061 heats the substrate W, in other words, when the hot plate is in the upper position. In this case, the amount of heat applied to the substrate W can be adjusted by changing the size of the clearance. In this modified example, the hot plate 1061 can heat the substrate W while the rotation mechanism 1030 rotates the substrate W. The speed of this rotation may be controlled to suppress variations in the rate of progression of the expansion of the hole OP. Specifically, the rotation speed may be reduced to suppress the progression of the expansion, and conversely, the rotation speed may be increased to promote the progression of the expansion.

In addition, other substrate heating means may be used instead of the hot plate 1061. For example, when a light-emitting diode (LED) heater is used as the substrate heating means, efficient heating is possible even if the substrate heating means and the substrate W are not in contact.

In the above, a configuration in which the substrate heating means is disposed below the substrate W has been described, but as a modified example, the substrate heating means may be disposed above the substrate W.

In addition, IPA has been used as an example of an organic solvent having a surface tension lower than that of water, but instead of IPA, for example, methanol, ethanol, acetone, or HFE (hydrofluoroether) may be used.

The above modifications can also be applied in a similar manner to the fifth embodiment described below.

<5. Fifth embodiment>
<5-1. Configuration of the substrate processing apparatus>
In the fifth embodiment, the substrate processing apparatus 1 (FIG. 1) is provided with a processing unit 2C (FIG. 45) instead of the processing unit 2 (FIG. 1). FIG. 45 is a cross-sectional view showing a schematic configuration of the processing unit 2C. The processing unit 2C has a light irradiation unit 1007 in addition to a configuration similar to that of the processing unit 2B (FIG. 29). The light irradiation unit 1007 has a light source 1071, a light source arm 1079, and a light source arm swing unit 1070. The light source 1071 is for generating light for the substrate W, and the substrate W is heated by absorbing this light. This light preferably has a component with a wavelength of 200 nm or more and 1100 nm or less. Even if a liquid film L of liquid IPA (organic solvent) exists on the substrate W, this light is not substantially absorbed by the IPA, so that the direct temperature increase effect by the light from the light source 1071 does not substantially act on the IPA but acts only on the substrate W. Thus, the heating effect of the IPA by the light source 1071 is an indirect effect due to heating by the substrate W heated by the light source 1071. The light source 1071 includes an LED. The light source 1071 may have a cover member exposed toward the substrate W, the cover member being made of, for example, quartz glass.

Figure 46 is a plan view showing the operation of the light irradiation unit 1007 (Figure 45). The light source 1071 of the light irradiation unit 1007 is attached to the tip of a light source arm 1079 extending almost horizontally with the light irradiation direction facing downward. Therefore, the light irradiated to the substrate W is irradiated from above the upper surface S2 of the substrate W. The light source arm 1079 is provided so as to be swingable around the rotation axis. A light source arm swinging unit 1070 for swinging the light source arm 1079 is connected to the light source arm 1079. By swinging the light source arm 1079, the light source 1071 is moved between the center of the substrate W held by the substrate rotation mechanism 1030 or the hot plate 1061 and a retreat position set outside the processing liquid collection unit 1050. The operation of the light source arm swinging unit 1070 is controlled by the controller 3. The intensity of the light generated by the light source 1071 is adjusted by the controller 3 controlling the power to the light source 1071. As a modified example, the light source 1071 may be attached to the third nozzle arm 1431 (FIG. 2), in which case the light source arm 1079 and the light source arm swing unit 1070 are omitted.

The light source 1071 using an LED generally tends to deteriorate gradually with operation. This deterioration state may be evaluated based on an image captured by the camera CM. For example, light is generated by the light irradiation unit 1007 and an image is captured by the camera CM under predetermined conditions, and the deterioration state of the light source 1071 can be evaluated from the brightness of this image. If it is evaluated that the intensity has decreased due to deterioration of the light source 1071, the power to the light source 1071 can be increased to compensate for this, thereby suppressing process fluctuations due to the above-mentioned deterioration. The timing of capturing images for this evaluation is arbitrary, but for example, images captured by the substrate processing method described below may be used for the evaluation.

<5-2. Substrate processing method>
The substrate processing method in this embodiment will be described below. The steps other than step S100 of the substrate processing method described in the fourth embodiment (FIG. 33) are common to this embodiment, and therefore their description will be omitted. In the drying process in step S100 (FIG. 33), the process of forming holes OP in the liquid film L is performed by discharging nitrogen gas (inert gas) (FIGS. 39 and 40) in the fourth embodiment, but is performed by irradiating the substrate W with light in this embodiment. Other features of the drying process are almost the same as those in the fourth embodiment. As in the description of the fourth embodiment, in this embodiment, the reference substrate processing, which is the substrate processing for the reference substrate (first substrate W), is performed first, and then the normal substrate processing, which is the substrate processing for the normal substrate (second substrate W), is performed.

As the above step S100, specifically, step S100h shown in FIG. 47 is performed on the reference substrate. Details of this step S100h are described below. Note that steps S101h and S102h are similar to the above-mentioned steps S101a and S102a (FIG. 34). Note that step S102h may include step S102hH of contacting the substrate W with a hot plate 1061 to heat the substrate W.

In step S103h (FIG. 47), the upper surface S2 of the first substrate W is irradiated with light under a predetermined condition (first condition). The first condition includes a setting condition for the intensity of the light irradiated to the substrate W and a setting condition for the irradiated region, which is the portion of the substrate W irradiated with the light. According to the first condition, as shown in FIG. 46, the irradiated region is disposed in the center of the substrate W. The temperature of the center of the substrate W is locally increased by the light irradiation in this arrangement. As a result, as shown in FIG. 41, a first hole OP is formed in the center of the first liquid film L held by the gas film VL (first gas film). Note that, in this step S103h, the substrate W may or may not be rotating. When the substrate W is rotated, the substrate W may be heated by the hot plate 1061 provided with a clearance with respect to the substrate W while the substrate W is held by the substrate holder 1020, as described in the modification of the fourth embodiment above.

Next, in step S104h (FIG. 47), light is irradiated onto the reference substrate (first substrate W) under a second predetermined condition different from the first condition described above. Specifically, the second condition includes an operating condition in which the substrate W is rotated as shown by the arrow RT (FIG. 46) while the light source 1071 is moved by a predetermined angle along the scanning direction CN (FIG. 46) to shift the irradiated area from the center of the substrate W. This causes the first hole OP to be expanded as shown by the arrow in FIG. 12. The expanded hole OP is photographed using the camera CM (FIG. 29) to obtain a hole image OQ (first image) (step S105h (FIG. 47)). This hole image OQ is then stored as a reference image (step S111h (FIG. 47)).

Next, the hole OP is further enlarged by irradiating the substrate W with light under a third predetermined condition (step S121h (FIG. 47)). The third condition may include a setting condition for the intensity of the light irradiated to the substrate W. The third condition may also include a setting condition for the moving speed of the irradiated region from the center to the outer periphery of the substrate W (in other words, the scanning speed of the light source 1071). The third condition may also include a setting condition for the rotation speed of the substrate W. The irradiated region is finally moved until it reaches the outer periphery of the substrate W, thereby removing the IPA liquid film L from the upper surface S2. This completes the drying process (step S100 (FIG. 33)) of the reference substrate (first substrate W).

As in the fourth embodiment described above, normal substrate processing (substrate processing of substrate W as a normal substrate) is performed after the reference substrate processing described above. As step S100 (FIG. 33) in the substrate processing, step S100h (FIG. 47) is performed for the reference substrate (first substrate W) described above, while step S100i (FIG. 48) is performed for the normal substrate (second substrate W). Details of step S100i are described below. Note that steps S101i and S102i are similar to the above-mentioned steps S101b and S102b (FIG. 42). Note that step S102i may include step S102iH in which the substrate W is brought into contact with a hot plate 1061 to heat the substrate W.

Next, step S103i (Figure 48) is performed in the same manner as step S103h (Figure 47) described above. Specifically, by irradiating the second substrate W with light under the first condition described above, a second hole OP is formed in the center of the second liquid film L held by the gas film VL (second gas film) as shown in Figure 41. Next, step S104i (Figure 48) is performed in the same manner as step S104h (Figure 47) described above. Specifically, by irradiating the substrate W with light under the second condition described above, the hole OP is enlarged as shown by the arrow in Figure 12.

Next, in step S105i (FIG. 48), the hole OP (FIG. 13) expanded by step S104i is photographed by camera CM (FIG. 45). As a result, an image (second image) of the expanded hole OP (FIG. 13) is obtained. Next, in step S111i, the hole (first hole) in the hole image OQ (first image) as the reference image is compared with the second hole OP in the second image. As a result, the progress of the expansion of the second hole OP is evaluated. Steps S104h and S104i are both processes set to the second condition, but in reality, due to the influence of process fluctuations, a difference occurs between the first hole OP by step S104h and the hole OP by step S104i. The comparison in step S111i may be performed by an image comparison unit (not shown) configured by the controller 3.

Next, in step S112i (FIG. 48), the third condition for irradiating the second substrate W with light is adjusted based on the progress of the expansion of the hole OP evaluated as described above. This adjustment may be performed by a condition adjustment unit (not shown) configured by the controller 3.

In the above comparison, for example, as shown in FIG. 13, the area AQ (a dotted area in FIG. 13) of the hole (first hole) in the hole image OQ (first image) may be compared with the area AP (a hatched area in FIG. 13) of the second hole OP in the second image (FIG. 13). In the example shown in FIG. 13, each of the areas AQ and AP is calculated in the irradiated area RR at the time of shooting, not for the entire upper surface S2 of the substrate W. Therefore, the above comparison is performed within the irradiated area RR. The irradiated area RR at the time of shooting may be calculated from the operating conditions of the light source arm swing unit 1070 (FIG. 46). When the area AP is larger than the area AQ, the third condition is adjusted so that the expansion of the hole OP is suppressed. Specifically, as an adjustment of the third condition, for example, the intensity of the light irradiated to the substrate W is adjusted to be smaller. Alternatively, for example, the moving speed (scanning speed) of the irradiated area RR is adjusted to be smaller. Alternatively, the rotation speed of the substrate W is adjusted to be smaller. The amount of adjustment may be a predetermined amount, or may be an amount corresponding to the difference between the areas AQ and AP. Conversely, when the area AP is smaller than the area AQ, the third condition is adjusted to promote the expansion of the hole OP.

As a modified example of the above comparison method (FIG. 13), for example, as shown in FIG. 14, the dimensions (dimension from reference point P1 to end point PQ) of the hole (first hole) in the hole image OQ (first image) may be compared with the dimensions (dimension from reference point P1 to end point PP) of the second hole OP in the second image (FIG. 14). In the example shown in FIG. 14, each dimension is calculated in the detection section LE extending outward from the reference point P1. The detection section LE is preferably within the irradiated region RR at the time of shooting, preferably along the scanning direction CN, and if the irradiated region RR has a circular shape, it may be the diameter of the circle along the scanning direction CN. If the dimensions (dimension from reference point P1 to end point PP) of the hole OP are larger than the dimensions (dimension from reference point P1 to end point PQ) of the hole image OQ, the third condition is adjusted so that the expansion of the hole OP is suppressed. Conversely, if the dimension of the hole OP (the dimension from the reference point P1 to the end point PP) is smaller than the dimension of the hole image OQ (the dimension from the reference point P1 to the end point PQ), the third condition is adjusted to promote the expansion of the hole OP. The amount of adjustment may be a predetermined amount, or may be an amount corresponding to the magnitude of the difference in dimensions described above.

Next, the hole OP is further enlarged (step S121i (FIG. 48)) by irradiating the substrate W with light under the third condition adjusted in step S112i (FIG. 48) above. Finally, the irradiated area is moved until it reaches the outer periphery of the substrate W, thereby removing the IPA liquid film L from the upper surface S2. This completes the drying process (step S100 (FIG. 33)) for the normal substrate (second substrate W).

<5-3. Effects>
According to this embodiment, the progress of the expansion of the second hole OP caused by irradiating the normal substrate with light under a predetermined condition (second condition) is evaluated based on the progress of the expansion of the first hole OP caused by irradiating the reference substrate with light under the predetermined condition (second condition). By adjusting the condition (third condition) for further irradiating the normal substrate with light based on this progress, the progress speed of the further expansion of the second hole OP can be made closer to the standard progress speed. This makes it possible to suppress the variation in the progress speed of the expansion of the second hole OP of the liquid film L on the upper surface S2 of the normal substrate. Therefore, it is possible to suppress the adverse effect on the upper surface S2 of the substrate W caused by the variation. Specifically, it is possible to suppress the collapse of the structure 961 of the pattern 960 provided on the upper surface S2 of the normal substrate.

Since light is irradiated onto the substrate W from above, the light source 1071 is positioned above the substrate W. This makes it difficult for the chemical solution discharged onto the substrate W to adhere to the light source 1071 and its associated members. This makes it possible to avoid damage to the light source 1071 and its associated members caused by the chemical solution. This effect is particularly significant when a highly corrosive chemical solution such as hydrofluoric acid is used.

The third condition may include a setting condition for the intensity of the light irradiated onto the normal substrate. The third condition may include a setting condition for the scanning speed of the irradiated region RR. The third condition may include a setting condition for the rotation speed of the normal substrate. By using at least one of these setting conditions, the progress speed of the further expansion of the second hole OP can be effectively adjusted.

The comparison of the first hole OP of the reference substrate with the second hole OP of the normal substrate to evaluate the progress may be performed within the irradiated region RR. This can increase the reliability of the evaluation.

As described above, the comparison of the first hole OP of the reference board and the second hole OP of the normal board to evaluate the progress may be performed by comparing the area AQ of the hole image OQ of the reference board and the area AP of the hole OP of the normal board, as shown in FIG. 13. In this case, it is possible to average out the effects of expansion in various directions and perform an evaluation. Alternatively, the comparison of the first hole OP of the reference board and the second hole OP of the normal board to evaluate the progress may be performed by comparing the dimensions of the hole image OQ of the reference board and the hole OP of the normal board, as shown in FIG. 14. In this case, evaluation can be performed in a simple manner.

It is preferable that the deterioration state of the light source 1071 is evaluated based on the image captured by the camera CM. This makes it possible to suppress variation in the rate at which the hole OP expands due to irradiation with light from the light source 1071.

<5-4. Modified Examples>
Fig. 49 shows a light source 1072 as a first modified example of the light irradiation unit 1007 shown in Fig. 46. The light source 1072 has a plurality of light-emitting parts RL arranged at different positions in the radial direction of the substrate W. The light-emitting parts RL1 to RL9 included in the plurality of light-emitting parts RL are arranged in order from the center CT, which is the center of rotation of the substrate W in a plan view, toward the outside. The light-emitting parts RL1 to RL9 can be individually controlled by the controller 3. For example, the light-emitting parts RL1 to RL9 selectively emit light in this order, thereby making it possible to perform light irradiation that is substantially the same as the scanning operation of the light source 1071. According to this modified example, the light source arm 1079 and the light source arm swing unit 1070 can be omitted.

Figure 50 shows a light source 1073 as a second modified example of the light irradiation unit 1007 shown in Figure 46. In the light source 1073, each of the light-emitting parts RL extends along a circumference around the center CT. According to this modified example, unlike the first modified example described above, light irradiation can be performed on almost the entire substrate W without rotating the substrate W. Furthermore, when the multiple light-emitting parts RL are caused to emit light all over, the substrate W can be heated all over, so that the heating performed by the hot plate 1061 in the above can also be performed by the light source 1073. Therefore, in this case, the hot plate 1061 may be omitted.

In the above embodiment and its modified example, light is irradiated onto the upper surface S2 of the substrate W from above the substrate W, but light may also be irradiated onto the lower surface S1 of the substrate W from below the substrate W.

6. Modifications of each embodiment
In each of the above-described embodiments, the reference substrate processing and the normal substrate processing may be performed by the same substrate processing apparatus, or may be performed instead or together with the same substrate processing apparatus by different substrate processing apparatuses. When the reference substrate processing and the normal substrate processing are performed by the same substrate processing apparatus, the reference substrate processing and the normal substrate processing may be performed by the same processing unit, or may be performed instead or together with the same processing unit by different substrate processing apparatuses. When the reference substrate processing and the normal substrate processing are performed by different substrate processing apparatuses, information obtained by the reference substrate processing by one substrate processing apparatus (including information on a reference image, which will be described later) may be sent out by that substrate processing apparatus, and the other substrate processing apparatus performing the normal substrate processing may receive that information.

After multiple substrate processes that are candidates for the reference substrate process are performed, the reference substrate process may be set by selecting the candidate that has the best processing result. This selection may be performed by the controller receiving the selection from the outside, or may be performed automatically by the controller. The multiple substrate processes that are candidates for the reference substrate process may be performed by the same substrate processing apparatus, or may be performed instead or in addition by different substrate processing apparatus. When multiple substrate processes that are candidates for the reference substrate process are performed by the same substrate processing apparatus, the multiple substrate processes may be performed by repeating substrate processing by the same processing unit, or may be performed instead or in addition by multiple processing units.

Although this invention has been described in detail, the above description is merely illustrative in all respects and does not limit the invention. It is understood that countless variations not illustrated can be envisioned without departing from the scope of this invention. The configurations described in the above embodiments and variations can be combined or omitted as appropriate as long as they are not mutually contradictory.

1: Substrate processing apparatus 2: Processing unit 2A: Processing unit 2B: Processing unit 2C: Processing unit 3: Controller 6: Heater unit 10: Low surface tension liquid nozzle 12: Lamp unit 62: Heater 130: Upper surface head 133: Organic solvent nozzle 134: First gas nozzle 146: Organic solvent valve 152: First lamp heater 960: Pattern 1007: Light irradiation unit 1061: Hot plate 1071: Light source 1072: Light source 1073: Light source 1432: Third nozzle head 1432a: IPA outlet 1432b: Vertical outlet 1432c: Inclined outlet CM: Camera IM: Imaging unit L: Liquid film OP: Hole VL: Gas film W: Substrate

Claims (16)

(a) forming a first liquid film of an organic solvent on a first substrate;
(b) forming a first gas film supporting the first liquid film on an upper surface of the first substrate by heating the first substrate;
(c) forming a first hole in the first liquid film held by the first gas film by irradiating the first substrate with light under a first predetermined condition;
(d) enlarging the first hole by irradiating the first substrate with light under second predetermined conditions different from the first conditions;
(e) acquiring a first image by photographing the first hole expanded by the step (d);
(f) storing the first image as a reference image;
(g) forming a second liquid film of an organic solvent on a second substrate after the step (f);
(h) forming a second gas film supporting the second liquid film on an upper surface of the second substrate by heating the second substrate;
(i) forming a second hole in the second liquid film held by the second gas film by irradiating the second substrate with light under the first condition;
(j) enlarging the second hole by irradiating the second substrate with light under the second condition;
(k) acquiring a second image by photographing the second hole enlarged by step (j);
(l) evaluating the progress of the expansion of the second hole by comparing the first hole in the first image as the reference image with the second hole in the second image;
(m) adjusting a third condition for irradiating the second substrate with light based on the progress evaluated by step (l);
(n) further expanding the second hole by irradiating the second substrate with light under the third condition;
A substrate processing method comprising: 2. The substrate processing method according to claim 1,
The substrate processing method, wherein the step (b) includes the step of irradiating the first substrate with light to heat the first substrate. 3. The substrate processing method according to claim 1, further comprising the steps of:
The second substrate is provided on the top surface with a pattern. 4. A substrate processing method according to claim 1, further comprising:
a substrate processing method, wherein in steps (c) and (d), light is irradiated onto the first substrate from above the top surface of the first substrate, and in steps (i), (j), and (n), light is irradiated onto the second substrate from above the top surface of the second substrate. 5. A substrate processing method according to claim 1, further comprising the steps of:
The substrate processing method, wherein the third condition includes a setting condition for an intensity of light irradiated to the second substrate. 6. A substrate processing method according to claim 1, further comprising the steps of:
A substrate processing method, wherein the third condition includes a setting condition for a moving speed of an irradiated region, which is a portion of the second substrate that is irradiated with light. 7. The substrate processing method according to claim 6, further comprising the steps of:
The method for processing a substrate, wherein the step (l) is performed by a comparison within the irradiated region. 8. A substrate processing method according to claim 1, further comprising the steps of:
The substrate processing method, wherein the third condition includes a setting condition for a rotation speed of the second substrate. 9. A substrate processing method according to claim 1, further comprising the steps of:
A substrate processing method, wherein the step (l) includes a step of comparing an area of the first hole in the first image with an area of the second hole in the second image. 10. A substrate processing method according to claim 1 , further comprising:
The substrate processing method, wherein the step (l) includes a step of comparing a dimension of the first hole in the first image with a dimension of the second hole in the second image. 11. A substrate processing method according to claim 1, further comprising:
In steps (i), (j) and (n), the light to the second substrate is generated by a light source;
In the step (k), the second image is taken by a camera;
The substrate processing method includes:
(o) evaluating a deterioration state of the light source based on an image captured by the camera. (a) forming a first liquid film of an organic solvent on a first substrate;
(b) forming a first gas film supporting the first liquid film on an upper surface of the first substrate by heating the first substrate;
(c) forming a first hole in the first liquid film held by the first gas film by discharging an inert gas onto the top surface of the first substrate under a first predetermined condition;
(d) expanding the first hole by discharging an inert gas onto the first substrate under a second predetermined condition different from the first condition;
(e) acquiring a first image by photographing the first hole expanded by the step (d);
(f) storing the first image as a reference image;
(g) forming a second liquid film of an organic solvent on a second substrate after the step (f);
(h) forming a second gas film supporting the second liquid film on an upper surface of the second substrate by heating the second substrate;
(i) forming a second hole in the second liquid film held by the second gas film by discharging an inert gas onto the top surface of the second substrate under the first condition;
(j) expanding the second hole by discharging an inert gas onto the top surface of the second substrate under the second condition;
(k) acquiring a second image by photographing the second hole expanded by step (j);
(l) evaluating the progress of the expansion of the second hole by comparing the first hole in the first image as the reference image with the second hole in the second image;
(m) adjusting a third condition for discharging an inert gas onto the upper surface of the second substrate based on the progress evaluated by the step (l);
(n) further expanding the second hole by discharging an inert gas onto the top surface of the second substrate under the third condition;
A substrate processing method comprising: 13. The method of claim 12, further comprising the steps of:
The second substrate is provided on the top surface with a pattern. 14. The substrate processing method according to claim 12, further comprising the steps of:
The third condition includes a setting condition for a flow rate of an inert gas discharged onto the upper surface of the second substrate. 15. A substrate processing method according to claim 12, further comprising the steps of:
A substrate processing method, wherein the step (l) includes a step of comparing an area of the first hole in the first image with an area of the second hole in the second image. 16. A substrate processing method according to claim 12, further comprising the steps of:
The substrate processing method, wherein the step (l) includes a step of comparing a dimension of the first hole in the first image with a dimension of the second hole in the second image.

Images