WO2022138291A1

WO2022138291A1 - Substrate treatment apparatus, substrate treatment method, and storage medium

Info

Publication number: WO2022138291A1
Application number: PCT/JP2021/045865
Authority: WO
Inventors: 悠一郎松岡; 光赤田; 聖人林; 恭満山口
Original assignee: 東京エレクトロン株式会社
Priority date: 2020-12-24
Filing date: 2021-12-13
Publication date: 2022-06-30
Also published as: TW202234488A; JPWO2022138291A1

Abstract

A substrate treatment apparatus according to an aspect of the present invention comprises: a liquid treatment unit (U1) configured to rotate a substrate (W) that that a film (AF) of a treatment liquid is formed on a surface (Wa); projection units (70A-70C) configured to radiate light to a location superposed on the surface of the substrate in a rotation period during which the substrate is rotated; light-receiving units (70A-70C) configured to receive reflected light obtained by synthesis of light emitted via the film of the treatment liquid after being reflected by the surface of the substrate, and light reflected by the outer surface of the film of the treatment liquid; and a control unit (100). The control unit has: a signal acquisition unit (124) configured to acquire a signal waveform that indicates a time variation in the intensity of the reflected light in the rotation period; and a film thickness calculation unit (128) configured to calculate the thickness of the film of the treatment liquid at a prescribed measurement time in the rotation period, on the basis of the waveform between the measurement time and a time at which the signal waveform satisfies a prescribed condition at or before the measurement time in the signal waveform.

Description

Board processing equipment, board processing method, and storage medium

The present disclosure relates to a substrate processing apparatus, a substrate processing method, and a storage medium.

In Patent Document 1, a film thickness measuring means placed along the radial direction of a substrate having a film formed on the surface, and a chemical solution discharge amount and a chemical solution based on the measurement results output from the film thickness measuring means. A substrate processing apparatus having an arithmetic control unit for controlling a reciprocating speed of a nozzle and a substrate rotation speed is disclosed.

Japanese Unexamined Patent Publication No. 1-276722

The present disclosure provides a substrate processing apparatus, a substrate processing method, and a storage medium capable of accurately estimating the film thickness based on the reflected light from the substrate.

The substrate processing apparatus according to one aspect of the present disclosure is a liquid configured to rotate a substrate in a state where the treatment liquid is supplied on the surface so that a film of the treatment liquid is formed on the surface of the substrate. A processing unit, a light projecting unit configured to irradiate light toward a portion overlapping the surface of the substrate during a rotation period in which the liquid processing unit rotates the substrate, and a processing liquid after reflecting the surface of the substrate. A light receiving unit configured to receive the reflected light obtained by combining the light emitted through the film and the light reflected on the outer surface of the processing liquid film, the liquid processing unit, the light projecting unit, and the light emitting unit. It includes a control unit that controls the light receiving unit. The control unit has a signal acquisition unit configured to acquire a signal waveform indicating a time change in the intensity of the reflected light during the rotation period based on the reflected light received by the light receiving unit, and a signal waveform acquired by the signal acquisition unit. Of these, the thickness of the processing liquid film at the measurement time point is calculated based on the waveform between the predetermined measurement time point within the rotation period and the time point where the signal waveform satisfies the predetermined condition before the measurement time point. It has a film thickness calculation unit configured in.

According to the present disclosure, a substrate processing apparatus, a substrate processing method, and a storage medium capable of accurately estimating the film thickness based on the reflected light from the substrate are provided.

FIG. 1 is a schematic diagram showing an example of a substrate processing system. FIG. 2 is a schematic view showing an example of a coating and developing apparatus. FIG. 3 is a schematic diagram showing an example of a liquid treatment unit and a measurement unit. FIG. 4 is a schematic diagram showing an example of the irradiation position of light from the measuring unit. 5 (a) and 5 (b) are schematic views for explaining the relationship between the film thickness and the reflected light. FIG. 6 is a block diagram showing an example of the functional configuration of the control device. FIG. 7 is a block diagram showing an example of the hardware configuration of the control device. FIG. 8 is a flowchart showing an example of the substrate processing method. FIG. 9 is a graph showing an example of the time change of the intensity of the reflected light. FIG. 10 is a flowchart showing an example of a method for generating a model formula for estimating the film thickness. FIG. 11 is a schematic diagram showing an example of the measuring unit. FIG. 12 is a schematic diagram showing an example of the measuring unit. 13 (a) and 13 (b) are schematic views showing an example of a measuring unit. FIG. 14 is a graph for explaining an example of the film thickness estimation method. 15 (a) and 15 (b) are graphs for explaining an example of the film thickness estimation method. FIG. 16 is a graph for explaining an example of the film thickness estimation method.

Hereinafter, various exemplary embodiments will be described.

The substrate processing apparatus according to one exemplary embodiment is configured to rotate a substrate in a state where the treatment liquid is supplied on the surface so that a film of the treatment liquid is formed on the surface of the substrate. The liquid treatment unit, the light projecting unit configured to irradiate light toward the portion overlapping the surface of the substrate during the rotation period during which the liquid treatment unit rotates the substrate, and the processing after reflecting the surface of the substrate. A light receiving unit configured to receive the reflected light obtained by combining the light emitted through the liquid film and the light reflected on the outer surface of the processing liquid film, the liquid treatment unit, and the light projecting unit. It also includes a control unit that controls the light receiving unit. The control unit has a signal acquisition unit configured to acquire a signal waveform indicating a time change in the intensity of the reflected light during the rotation period based on the reflected light received by the light receiving unit, and a signal waveform acquired by the signal acquisition unit. Of these, the thickness of the processing liquid film at the measurement time point is calculated based on the waveform between the predetermined measurement time point within the rotation period and the time point where the signal waveform satisfies the predetermined condition before the measurement time point. It has a film thickness calculation unit configured in.

In this substrate processing apparatus, the time change of the intensity of the reflected light obtained by combining the light emitted through the film of the treatment liquid after reflecting on the surface of the substrate and the light reflected on the outer surface of the film of the treatment liquid is changed. The indicated signal waveform is acquired. Depending on the thickness of the film of the treatment liquid, the state of interference between the light emitted through the film of the treatment liquid after reflecting on the surface of the substrate and the light reflected on the outer surface of the film of the treatment liquid changes. , The signal waveform contains information about the film thickness of the treatment liquid. Therefore, the film thickness of the processing liquid can be calculated from the waveform between the predetermined measurement time point within the rotation period and the time point where the signal waveform satisfies the predetermined condition before the measurement time point among the signal waveforms. .. In the substrate processing apparatus, the thickness of the film of the treatment liquid is calculated from the time change of the intensity of the reflected light. Therefore, even if the thickness of the film of the treatment liquid fluctuates, the film of the treatment liquid can be used. It is possible to estimate the thickness with high accuracy.

The control unit further has a feature amount acquisition unit configured to acquire the feature amount from the waveform between the measurement time point and the time point when the signal waveform satisfies a predetermined condition among the signal waveforms. You may. The film thickness calculation unit may be configured to calculate the film thickness of the treatment liquid at the time of measurement based on the feature amount acquired by the feature amount acquisition unit. Since the signal waveform contains information about the film thickness of the treatment liquid, the feature amount obtained from a part of the waveform can correlate with the film thickness of the treatment liquid. Therefore, by utilizing the correlation between the feature amount and the film thickness, the calculation for calculating the film thickness of the treatment liquid is simplified.

The light projecting unit may be configured to irradiate light toward the above-mentioned part and another part overlapping the surface of the substrate at a position different from the above-mentioned part. In this case, by further acquiring the signal waveform based on the reflected light from another location, it is possible to estimate the film thickness of the processing liquid at a plurality of locations.

The distance between the above-mentioned location and the center of the substrate and the distance between the above-mentioned other location and the center of the substrate may be different from each other. In this case, it is possible to measure the film thickness at positions where the distances from the center of the substrate are different from each other.

The liquid treatment unit may have a support unit configured to support the substrate. The above-mentioned portion may be set so as to overlap with the support portion. The thickness of the portion of the film of the treatment liquid corresponding to the support portion may be affected by the support portion. In the above configuration, since the film thickness at the portion affected by the support portion is estimated, it is possible to evaluate the film thickness after taking the relevant portion into consideration.

The light projecting unit is configured to irradiate the above-mentioned part with light having a predetermined frequency and to irradiate the above-mentioned other part with another light having a frequency different from the frequency of the light irradiating the part. You may. In this configuration, even when a part of the reflected light from another place is received by the light receiving portion, it is easy to remove the influence of a part of the reflected light from another place from the signal waveform.

The light projecting unit is configured to divide the light from one light source that generates the light to irradiate the substrate and the light from one light source into the light radiated to the above-mentioned place and the light radiated to the other place. It may have a branch portion. In this case, when the film thickness is estimated by irradiating a plurality of places with light, the number of light sources can be reduced, and the apparatus can be simplified.

The liquid treatment unit may have a housing that forms an internal space for processing the substrate with the treatment liquid. The light projecting unit may have a light source that generates light to irradiate the substrate. The light source may be provided on the inner wall of the housing or may be arranged outside the housing. When the light source is placed near the substrate, the film thickness can vary due to the heat of the light source. On the other hand, in the above configuration, since the light source and the substrate subjected to the liquid treatment can be separated from each other, it is possible to reduce the influence of the heat of the light source on the liquid treatment.

The light projecting unit may have a mirror member configured to change the direction of the light irradiating the substrate by reflecting the light. When the member is arranged vertically above the substrate, it affects the airflow above the substrate and the film thickness may fluctuate. On the other hand, in the above configuration, since the portion included in the light projecting unit to be irradiated with light can be arranged away from the substrate, it is possible to reduce the influence of the light projecting unit on the liquid treatment.

The reflective surface of the mirror member may be formed with a film configured to suppress scattering and absorption of incident light on the reflective surface. In this case, it is possible to suppress a decrease in the amount of light received by the light receiving unit while reducing noise contained in the light received by the light receiving unit. As a result, it becomes possible to estimate the film thickness with higher accuracy based on the signal waveform.

The substrate processing apparatus may further include an adjusting member configured to adjust the light receiving state of the reflected light in the light receiving portion according to the vertical positional deviation of the substrate or the warp of the substrate. In this case, even if the effect of the vertical displacement of the substrate or the warp of the substrate is added to the reflected light, the effect is reduced from the reflected light by the adjusting member before the light receiving portion receives the reflected light. .. As a result, it becomes possible to stabilize the estimation of the film thickness.

The control unit may further have a condition setting unit configured to change the set value of the light intensity from the light projecting unit based on the comparison result between the intensity of the reflected light and a predetermined threshold value. In this case, when the intensity of the reflected light received by the light receiving unit is lowered, the intensity of the reflected light can be maintained by increasing the set value of the intensity of the light from the light projecting unit. As a result, it becomes possible to stabilize the estimation of the film thickness.

The substrate processing method according to one exemplary embodiment is to rotate the substrate in a state where the treatment liquid is supplied on the surface so that a film of the treatment liquid is formed on the surface of the substrate, and to rotate the substrate. During the rotating period, the light is irradiated toward the part that overlaps the surface of the substrate, the light emitted through the film of the treatment liquid after reflecting the surface of the substrate, and the outside of the film of the treatment liquid. Of the signal waveforms, receiving the reflected light that is combined with the light reflected on the surface, and acquiring the signal waveform showing the time change of the intensity of the reflected light during the rotation period based on the received reflected light. The thickness of the film of the processing liquid at the time of measurement is calculated based on the waveform between the predetermined measurement time point within the rotation period and the time point where the signal waveform satisfies the predetermined condition before the measurement time point. include. In this substrate processing method, as in the case of the substrate processing apparatus, the thickness of the film of the treatment liquid is calculated from the time change of the intensity of the reflected light, so that the thickness of the film of the treatment liquid may fluctuate. However, it is possible to accurately estimate the film thickness of the treatment liquid.

The storage medium according to one exemplary embodiment is a computer-readable storage medium that stores a program for causing the board processing apparatus to execute the board processing method.

Hereinafter, some embodiments will be described in detail with reference to the drawings. In the description, the same elements or elements having the same function are designated by the same reference numerals, and duplicate description will be omitted.

[Board processing system]
The substrate processing system 1 (substrate processing apparatus) shown in FIG. 1 is a system that forms a photosensitive film, exposes the photosensitive film, and develops the photosensitive film on the work W. The work W to be processed is, for example, a substrate or a substrate in which a film, a circuit, or the like is formed by being subjected to a predetermined treatment. The substrate is, for example, a silicon wafer. The work W (board) may be circular. The work W may be a glass substrate, a mask substrate, an FPD (Flat Panel Display), or the like. The photosensitive film is, for example, a resist film.

As shown in FIGS. 1 and 2, the substrate processing system 1 includes a coating and developing device 2, an exposure device 3, and a control device 100 (control unit). The exposure device 3 is a device that exposes a resist film (photosensitive film) formed on the work W (substrate). Specifically, the exposure apparatus 3 irradiates the exposed portion of the resist film with energy rays by a method such as immersion exposure.

The coating and developing apparatus 2 performs a process of applying a resist (chemical solution) to the surface of the work W to form a resist film before the exposure process by the exposure apparatus 3, and develops the resist film after the exposure process. The coating and developing apparatus 2 includes a carrier block 4, a processing block 5, and an interface block 6.

The carrier block 4 introduces the work W into the coating / developing device 2 and derives the work W from the coating / developing device 2. For example, the carrier block 4 can support a plurality of carriers C for the work W, and has a built-in transfer device A1 including a transfer arm. The carrier C accommodates, for example, a plurality of circular workpieces W. The transport device A1 takes out the work W from the carrier C, passes it to the processing block 5, receives the work W from the processing block 5, and returns it to the carrier C. The processing block 5 has

processing modules

11, 12, 13, and 14.

The processing module 11 incorporates a liquid processing unit U1, a heat treatment unit U2, and a transfer device A3 for transporting the work W to these units. The treatment module 11 forms an underlayer film on the surface of the work W by the liquid treatment unit U1 and the heat treatment unit U2. Examples of the lower layer film include an SOC (Spin On Carbon) film. The liquid treatment unit U1 applies a treatment liquid for forming an underlayer film onto the work W. The heat treatment unit U2 performs various heat treatments accompanying the formation of the underlayer film.

The processing module 12 incorporates a liquid processing unit U1, a heat treatment unit U2, and a transfer device A3 for transporting the work W to these units. The treatment module 12 forms a resist film on the lower layer film by the liquid treatment unit U1 and the heat treatment unit U2. The liquid treatment unit U1 forms a film of the treatment liquid on the lower layer film (on the surface of the work W) by applying the treatment liquid for forming the resist film on the lower layer film. The heat treatment unit U2 performs various heat treatments accompanying the formation of the resist film.

The processing module 13 incorporates a liquid processing unit U1, a heat treatment unit U2, and a transfer device A3 for transporting the work W to these units. The treatment module 13 forms an upper layer film on the resist film by the liquid treatment unit U1 and the heat treatment unit U2. The liquid treatment unit U1 applies a treatment liquid for forming an upper layer film onto the resist film. The heat treatment unit U2 performs various heat treatments accompanying the formation of the upper layer film.

The processing module 14 incorporates a liquid processing unit U1, a heat treatment unit U2, and a transfer device A3 for transporting the work W to these units. The processing module 14 uses the liquid treatment unit U1 and the heat treatment unit U2 to develop the exposed resist film and perform heat treatment associated with the development treatment. The liquid treatment unit U1 develops a resist film by applying a developing solution on the surface of the exposed work W and then rinsing it with a rinsing solution. The heat treatment unit U2 performs various heat treatments associated with the development process. Specific examples of the heat treatment include heat treatment before development (PEB: Post Exposure Bake), heat treatment after development (PB: Post Bake), and the like.

A shelf unit U10 is provided on the carrier block 4 side in the processing block 5. The shelf unit U10 is divided into a plurality of cells arranged in the vertical direction. A transport device A7 including an elevating arm is provided in the vicinity of the shelf unit U10. The transport device A7 raises and lowers the work W between the cells of the shelf unit U10.

A shelf unit U11 is provided on the interface block 6 side in the processing block 5. The shelf unit U11 is divided into a plurality of cells arranged in the vertical direction.

The interface block 6 transfers the work W to and from the exposure apparatus 3. For example, the interface block 6 has a built-in transfer device A8 including a transfer arm, and is connected to the exposure device 3. The transport device A8 passes the work W arranged in the shelf unit U11 to the exposure device 3. The transport device A8 receives the work W from the exposure device 3 and returns it to the shelf unit U11.

The control device 100 controls the coating / developing device 2 so as to execute the coating / developing process in the following procedure, for example. First, the control device 100 controls the transfer device A1 so as to transfer the work W in the carrier C to the shelf unit U10, and controls the transfer device A7 so as to arrange the work W in the cell for the processing module 11.

Next, the control device 100 controls the transfer device A3 so as to transfer the work W of the shelf unit U10 to the liquid processing unit U1 and the heat treatment unit U2 in the processing module 11. Further, the control device 100 controls the liquid treatment unit U1 and the heat treatment unit U2 so as to form a lower layer film on the surface of the work W. After that, the control device 100 controls the transfer device A3 so as to return the work W on which the lower layer film is formed to the shelf unit U10, and controls the transfer device A7 so as to arrange the work W in the cell for the processing module 12. ..

Next, the control device 100 controls the transfer device A3 so as to transfer the work W of the shelf unit U10 to the liquid processing unit U1 and the heat treatment unit U2 in the processing module 12. Further, the control device 100 controls the liquid treatment unit U1 and the heat treatment unit U2 so as to form a resist film on the lower film of the work W. After that, the control device 100 controls the transfer device A3 so as to return the work W to the shelf unit U10, and controls the transfer device A7 so as to arrange the work W in the cell for the processing module 13.

Next, the control device 100 controls the transfer device A3 so as to transfer the work W of the shelf unit U10 to each unit in the processing module 13. Further, the control device 100 controls the liquid treatment unit U1 and the heat treatment unit U2 so as to form an upper layer film on the resist film of the work W. After that, the control device 100 controls the transfer device A3 so as to transfer the work W to the shelf unit U11.

Next, the control device 100 controls the transport device A8 so as to send the work W of the shelf unit U11 to the exposure device 3. After that, the control device 100 controls the transfer device A8 so as to receive the exposed work W from the exposure device 3 and arrange it in the cell for the processing module 14 in the shelf unit U11.

Next, the control device 100 controls the transfer device A3 so as to transfer the work W of the shelf unit U11 to each unit in the processing module 14, and the liquid processing unit U1 so as to develop the resist film of the work W. And control the heat treatment unit U2. After that, the control device 100 controls the transfer device A3 so as to return the work W to the shelf unit U10, and controls the transfer device A7 and the transfer device A1 so as to return the work W to the carrier C. This completes the coating and developing process for one piece of work W. The control device 100 controls the coating / developing device 2 so as to execute the coating / developing process in the same manner as described above for each of the subsequent plurality of work Ws.

The specific configuration of the substrate processing apparatus is not limited to the configuration of the substrate processing system 1 exemplified above. The substrate processing apparatus may be any as long as it includes a liquid treatment unit that supplies the treatment liquid to the substrate and performs the liquid treatment, and a control device that can control the liquid treatment unit.

(Liquid treatment unit)
Subsequently, an example of the liquid processing unit U1 of the processing module 12 will be described with reference to FIG. After supplying the treatment liquid to the surface Wa of the work W, the liquid treatment unit U1 (liquid treatment unit) forms a film of the treatment liquid on the surface Wa of the work W in a state where the treatment liquid is supplied on the surface Wa. Rotate to be. Hereinafter, the film of the treatment liquid formed by the liquid treatment unit U1 is referred to as “coating film AF”. As shown in FIG. 3, the liquid treatment unit U1 has a rotation holding unit 30 and a processing liquid supply unit 40.

The rotation holding unit 30 holds and rotates the work W. The rotation holding unit 30 has, for example, a holding unit 32, a shaft 34, and a rotation driving unit 36. The holding portion 32 (supporting portion) supports the work W. The holding portion 32 supports, for example, the central portion of the work W arranged horizontally with the surface Wa facing up, and holds the work W by vacuum suction or the like. The upper surface (the surface supporting the work W) of the holding portion 32 may be formed in a circular shape when viewed from above, and has a radius of about 1/6 to 1/2 times the radius of the work W. May be good. A rotary drive unit 36 is connected below the holding unit 32 via a shaft 34.

The rotation drive unit 36 is an actuator including a power source such as an electric motor, and rotates the holding unit 32 around the vertical axis Ax. When the holding portion 32 is rotated by the rotation driving portion 36, the work W held (supported) by the holding portion 32 is rotated. The holding portion 32 may hold the work W so that the center CP of the work W (see FIG. 4) substantially coincides with the axis Ax.

The treatment liquid supply unit 40 supplies the treatment liquid to the surface Wa of the work W. The treatment liquid is a solution (resist) for forming a resist film. The processing liquid supply unit 40 has, for example, a nozzle 42, a supply source 44, an on-off valve 46, and a nozzle drive unit 48. The nozzle 42 discharges the processing liquid onto the surface Wa of the work W held by the holding portion 32. For example, the nozzle 42 is arranged above the work W (vertically above the center CP of the work W) and discharges the treatment liquid downward. The supply source 44 supplies the treatment liquid to the nozzle 42.

The on-off valve 46 is provided in the supply path between the nozzle 42 and the supply source 44. The on-off valve 46 switches the open / closed state of the supply path. The nozzle drive unit 48 moves the nozzle 42 between the discharge position above the work W and the retracted position away from the discharge position. The discharge position is, for example, a position vertically above the center of rotation of the work W (a position on the axis Ax). The standby position is set, for example, to a position outside the peripheral edge of the work W.

(Measurement unit)
The coating and developing apparatus 2 further includes a measuring unit 60 for measuring the thickness of the coating film AF of the processing liquid. The measuring unit 60 is provided in the liquid processing unit U1. The measuring unit 60 rotates the work W after the treatment liquid is supplied, and irradiates the rotating work W with light during the period when the coating film AF is formed. The measuring unit 60 irradiates the surface Wa of the work W held by the holding unit 32 with light that can pass through the coating film AF (treatment liquid) on the surface Wa, and generates light according to the irradiated light. Receives reflected light (reflected by work W).

The measuring unit 60 has, for example, light emitting and receiving devices 70A to 70C. Each of the light emitting and receiving devices 70A to 70C irradiates light toward the irradiation points P1 to P3 overlapping the surface Wa of the work W on the holding portion 32, and receives the reflected light reflected from the irradiation points P1 to P3. Each of the irradiation points P1 to P3 is a fixed fixed position and does not change even if the work W rotates. Each of the light emitting and receiving devices 70A to 70C irradiates the surface Wa of the work W with a laser beam as irradiation light. Each of the light emitting and receiving devices 70A to 70C irradiates a laser beam that can pass through the coating film AF of the treatment liquid formed on the surface Wa.

The laser light emitted from each of the light receiving and receiving devices 70A to 70C may be visible light or infrared light. The wavelength of the laser beam may be 500 nm to 1200 nm, 600 nm to 1100 nm, or 780 nm to 1000 nm. The wavelength of the laser beam may be set according to the type of the processing liquid. For example, the wavelength of the laser beam is set so as not to promote the reaction in the treatment liquid and to reduce the absorption of light.

The frequencies of the laser beams emitted from the light receiving and receiving devices 70A to 70C may be different from each other. That is, the frequency of the light emitted from the light emitting / receiving device 70A toward the irradiation point P1 is the frequency of the light emitted from the light receiving / receiving device 70B (light emitting / receiving device 70C) toward the irradiation point P2 (irradiation point P3). It may be different. The light source included in each of the light emitting and receiving devices 70A to 70C may be a laser diode or an LED. The beam width of the laser beam may be about several mm to several tens of mm.

As shown in FIG. 4, the irradiation points P1 to P3 of the light (laser light) from the light emitting and receiving devices 70A to 70C are set at different positions from each other. That is, the measuring unit 60 irradiates the irradiation point P1 (point) and the irradiation points P2 and P3 (different points) that overlap the surface Wa of the work W at a position different from the irradiation point P1. do. At the light irradiation point P1 from the light emitting / receiving device 70A, the light irradiation point P2 from the light emitting / receiving device 70B, and the light irradiation point P3 from the light emitting / receiving device 70C, the distances from the center CP of the work W are mutual. It's different. In one example, the distance between the irradiation point P1 and the center CP of the work W is smaller than the distance between the irradiation point P2 and the center CP of the work W. The distance between the irradiation point P2 and the center CP of the work W is smaller than the distance between the irradiation point P3 and the center CP of the work W.

The irradiation points P1, the irradiation points P2, and the irradiation points P3 may be arranged in a line in this order from the center CP of the work W along the radial direction of the work W. The irradiation points P1, the irradiation points P2, and the irradiation points P3 may be arranged at substantially equal intervals. The irradiation point P1 is located at the center of the surface Wa of the work W. Specifically, the irradiation point P1 is set so as to overlap the upper surface of the holding portion 32 (the surface supporting the back surface of the work W). The irradiation point P3 located on the outside is located in a region (peripheral region) in the vicinity of the peripheral edge of the work W. As described above, the light emitting and receiving devices 70A to 70C function as a light emitting unit that irradiates light toward a predetermined portion overlapping the surface Wa of the work W.

The light emitting and receiving devices 70A to 70C may generate an electric signal according to the intensity of the reflected light received. Since the laser beam can pass through the coating film AF on the surface Wa of the work W, it is reflected by the outer surface Fa (upper surface) of the coating film AF at the irradiation site, and the work W located below the coating film AF. After reflecting the surface Wa of the above, it is emitted through the coating film AF. In the present disclosure, the surface Wa of the work W on which a part of the laser beam is reflected is the surface of the base material contained in the work W or the surface of another film existing under the coating film AF and already solidified. .. The other film may be, for example, a film existing directly under the coating film AF (for example, the above-mentioned lower layer film).

The light emitting / receiving device 70A receives light emitted from the irradiation point P1. Specifically, in the light emitting / receiving device 70A, the light emitted through the coating film AF after reflecting the surface Wa of the work W at the irradiation point P1 and the light reflected by the outer surface Fa of the coating film AF are generated. It receives the reflected light obtained by synthesizing. At each of the irradiation points P2 and P3, the laser beam is reflected by the outer surface Fa of the coating film AF and the surface Wa located under the coating film AF. That is, the light emitting and receiving

devices

70B and 70C also receive the light emitted from the irradiation points P2 and P3, respectively, like the light emitting and receiving device 70A. More specifically, the light emitting and receiving

devices

70B and 70C reflect the light emitted through the coating film AF after reflecting the surface Wa of the work W at the irradiation points P2 and P3 and the light emitted by the outer surface Fa of the coating film AF. The reflected light obtained by synthesizing the combined light is received. As described above, the light receiving and receiving devices 70A to 70C are light receiving units that receive the reflected light obtained by combining the light reflected by the outer surface Fa and the light reflected by the surface Wa in the coating film AF of the treatment liquid on the surface Wa. Also works as.

Here, with reference to FIGS. 5 (a) and 5 (b), the time change of the intensity of the reflected light will be described. The reflected light has an intensity corresponding to the thickness of the coating film AF during the period in which the coating film AF of the treatment liquid is formed on the surface Wa of the work W. In FIGS. 5 (a) and 5 (b), the portion of any of the light emitting and receiving devices that irradiates the laser beam is indicated by the “light emitting unit 72”, and the portion that receives the reflected light is the “light receiving unit”. 74 ”. Note that, unlike FIG. 3, FIGS. 5 (a) and 5 (b) exemplify a case where light is incident on the surface Wa from an oblique direction.

As described above, the reflected light accompanying the laser beam radiated toward the surface Wa of the work W passes through the coating film AF of the treatment liquid, reflects the surface Wa, and then emits to the outside via the coating film AF. The light L1 to be generated and the light L2 reflected by the outer surface Fa of the coating film AF without being incident on the coating film AF are included. The reflected light received by the light receiving unit 74 is the reflected light Lc obtained by synthesizing the light L1 and the light L2. Depending on the thickness of the coating film AF, the phase of the light L2 with respect to the light L1 changes, and there are cases where they strengthen each other and cases where they weaken each other. As shown in FIG. 5A, when the peak portion of the amplitude in the light L1 and the peak portion of the amplitude in the light L2 overlap, the light L1 and the light L2 strengthen each other, and the intensity of the reflected light Lc increases. .. On the other hand, as shown in FIG. 5B, when the peak portion of the amplitude in the light L1 and the valley portion of the amplitude in the light L2 overlap, the light L1 and the light L2 weaken each other, and the intensity of the reflected light Lc becomes high. It gets smaller.

Immediately after the treatment liquid is supplied to the surface Wa, a liquid film of the treatment liquid is formed, and then by rotating the work W, solidification (volatilization) of the coating film AF gradually progresses. Therefore, the thickness of the coating film AF gradually decreases during the period in which the work W is rotated. As a result, the phase of the light L2 with respect to the light L1 also changes, and the states of strengthening each other and the states of weakening each other are alternately repeated. As a result, as a waveform showing the time change of the intensity of the reflected light, a waveform in which the peak portion and the valley portion are alternately repeated is obtained (see FIG. 9). In the substrate processing system 1 of the present disclosure, the thickness (film thickness) of the coating film AF is estimated based on this waveform. The details of the film thickness estimation method will be described later.

(Control device)
The control device 100 causes the coating / developing device 2 to execute the processing of the work W by partially or wholly controlling the coating / developing device 2. As shown in FIG. 6, the control device 100 has, for example, a processing information storage unit 112, a liquid processing control unit 114, and a film thickness estimation unit 120 as a functional configuration (hereinafter referred to as “functional module”). And have. The processing executed by these functional modules corresponds to the processing executed by the control device 100.

The processing information storage unit 112 stores processing information related to liquid processing for the work W. Various conditions for executing the liquid treatment are set in the processing information. For example, as setting values of various conditions, the timing (time) at which the discharge of the treatment liquid is started and stopped, the rotation speed (rotation speed) of the work W when the treatment liquid is discharged, and the coating on the surface Wa after the treatment liquid is supplied. The rotation speed of the work W when forming the film AF, the rotation time of the work W when forming the coating film AF, and the like are predetermined.

The liquid treatment control unit 114 controls the liquid treatment unit U1 so as to perform liquid treatment on the work W. The liquid processing control unit 114 controls the rotation holding unit 30 and the processing liquid supply unit 40 so as to execute liquid processing on the work W according to various conditions defined in the processing information stored in the processing information storage unit 112.

The film thickness estimation unit 120 acquires a waveform (hereinafter referred to as “signal waveform”) indicating the time change of the intensity of the reflected light from the work W from the measurement unit 60, and applies the coating film on the surface Wa based on the signal waveform. Estimate the thickness of the membrane AF. That is, the substrate processing system 1 has a film thickness estimation device 20 including a measurement unit 60 and a film thickness estimation unit 120 (see FIG. 4). As a functional module, the film thickness estimation unit 120 includes, for example, a light projection control unit 122, a signal acquisition unit 124, a feature amount acquisition unit 126, a film thickness calculation unit 128, and model information. A storage unit 132 and a model construction unit 134 are included. The process executed by these functional modules corresponds to the process executed by the film thickness estimation unit 120 (control device 100).

The light projection control unit 122 irradiates light toward the irradiation point overlapping the surface Wa of the work W during the rotation period in which the rotation holding unit 30 of the liquid treatment unit U1 rotates the work W after the treatment liquid is supplied. Controls the light emitting and receiving devices 70A to 70C. The light projection control unit 122 may start irradiation of light from the light emitting and receiving devices 70A to 70C before starting to discharge the processing liquid in the liquid treatment to the work W. The light projection control unit 122 stops the irradiation of light from the light emitting and receiving devices 70A to 70C after stopping the rotation for forming the coating film AF.

The signal acquisition unit 124 acquires a signal waveform indicating the time change of the intensity of the reflected light received by the irradiation device from each light emitting / receiving device during the above rotation period. The signal acquisition unit 124 may acquire the intensity of the reflected light at a predetermined sampling period. The sampling period is set to such an extent that the change in the interference state between the light L1 reflected by the surface Wa and the light L2 reflected by the outer surface Fa of the coating film AF can be grasped by the signal waveform. The sampling period may be set to about several tens of ms to several hundreds of ms.

The feature amount acquisition unit 126 is a waveform of the signal waveform acquired by the signal acquisition unit 124 between a predetermined measurement time point within the rotation period and a time point in which the signal waveform satisfies a predetermined condition before the measurement time point. Obtain the feature quantity from. The feature amount is a value obtained from the above signal waveform according to predetermined conditions, and correlates with the thickness of the coating film AF. The feature amount acquisition unit 126 acquires the feature amount from the signal waveform for each of the irradiation points P1 to P3, for example.

The film thickness calculation unit 128 calculates the film thickness of the coating film AF at the time of measurement based on the feature amount acquired by the feature amount acquisition unit 126. The film thickness calculation unit 128 calculates the thickness of the coating film AF based on the feature amount for each of the irradiation points P1 to P3, for example. The measurement time point may be set to any time point within the rotation period. The measurement time point is set, for example, at the end time point of the rotation period (time point when the rotation of the work W stops). In this case, the film thickness calculation unit 128 calculates the thickness of the coating film AF at the end of the rotation period. The film thickness calculation unit 128 may calculate the thickness of the coating film AF at the time of measurement based on the above-mentioned feature amount and the model formula constructed in advance for estimating the thickness of the coating film AF.

The model information storage unit 132 stores a model formula constructed in advance for estimating the thickness of the coating film AF. This model formula is constructed to show the relationship between the feature amount of the signal waveform and the estimated value of the film thickness.

The model building unit 134 generates a model formula for estimating the thickness of the coating film AF. For example, the model building unit 134 performs liquid processing on a plurality of test workpieces W by changing the rotation speed in a plurality of stages, and at each stage, a feature amount based on a signal waveform and a measurement time point. Obtain the measured value of the thickness of the coating film AF. Then, the model building unit 134 sets the estimated value and the feature amount of the thickness of the coating film AF based on the feature amount for each of the plurality of stages in which the rotation speed is changed and the measured value of the thickness of the coating film AF. Generate a model formula showing the relationship. The model building unit 134 may generate a model formula for each irradiation point, or may generate one model formula for a plurality of irradiation points.

The control device 100 is composed of one or a plurality of control computers. For example, the control device 100 has a circuit 150 shown in FIG. The circuit 150 includes one or more processors 152, a memory 154, a storage 156, an input / output port 158, and a timer 162. The storage 156 has a storage medium readable by a computer, such as a hard disk. The storage medium stores a program for causing the control device 100 to execute the substrate processing method and the film thickness estimation method described later. The storage medium may be a removable medium such as a non-volatile semiconductor memory, a magnetic disk, or an optical disk.

The memory 154 temporarily stores the program loaded from the storage medium of the storage 156 and the calculation result by the processor 152. The processor 152 constitutes each of the above-mentioned functional modules by executing the above program in cooperation with the memory 154. The input / output port 158 inputs / outputs an electric signal to / from the rotation holding unit 30, the processing liquid supply unit 40, the measuring unit 60, and the like in accordance with a command from the processor 152. The timer 162 measures the elapsed time, for example, by counting a reference pulse having a fixed cycle.

When the control device 100 is composed of a plurality of control computers, each functional module may be realized by an individual control computer. The control device 100 is for control including a control computer including a functional module for executing liquid treatment by the liquid treatment unit U1 and a functional module (thickness estimation unit 120) for estimating the thickness of the coating film AF. It may be configured with a computer. Alternatively, each of these functional modules may be realized by a combination of two or more control computers. In these cases, the plurality of control computers may be connected to each other so as to be able to communicate with each other, and the substrate processing method and the film thickness estimation method described later may be executed in cooperation with each other. The hardware configuration of the control device 100 is not necessarily limited to that constituting each functional module by a program. For example, each functional module of the control device 100 may be configured by a dedicated logic circuit or an ASIC (Application Specific Integrated Circuit) in which the logic circuit is integrated.

[Board processing method]
Subsequently, as an example of the substrate processing method, an example of a series of processing executed by the control device 100 will be described. In a series of processes executed by the control device 100, a process for performing liquid treatment by the liquid treatment unit U1 and a process for estimating the thickness of the coating film AF (film thickness estimation method) are performed in parallel. .. In the following, an example will be illustrated in which the end point of the rotation period after the end of supply of the treatment liquid is set to the measurement time point for estimating the film thickness (hereinafter referred to as “measurement time point MT”).

FIG. 8 is a flowchart showing an example of a series of processes executed by the control device 100 for liquid processing and estimation of film thickness. The control device 100 executes step S11, for example, by receiving a command from the host controller. In step S11, for example, the liquid treatment control unit 114 controls the rotation holding unit 30 so as to start the rotation of the work W. The liquid processing control unit 114 controls the rotation holding unit 30 so that the work W rotates at a set value of the rotation speed at the time of discharging the processing liquid after the rotation of the work W starts.

Next, the control device 100 executes steps S12 and S13. In step S12, for example, the film thickness estimation unit 120 waits until a predetermined measurement start time is reached. The measurement start time is, for example, a time determined based on the time when a command from the host controller is received. In step S13, for example, the film thickness estimation unit 120 controls the measurement unit 60 so as to start measuring the intensity of the reflected light. In one example, the light projection control unit 122 controls the light emitting and receiving devices 70A to 70C so as to start irradiation of laser light toward the irradiation points P1 to P3, respectively. Then, the signal acquisition unit 124 starts acquiring the intensity of the reflected light accompanying the irradiation of the laser light from each of the light emitting / receiving devices 70A to 70C. In the subsequent processing, irradiation of the laser beam and acquisition of the intensity of the reflected light are continued.

Next, the control device 100 executes steps S14 and S15. In step S14, for example, the liquid treatment control unit 114 waits until a predetermined discharge start time is reached. The discharge start time is, for example, a time determined based on the time when a command from the host controller is received. In step S15, for example, the liquid processing control unit 114 controls the processing liquid supply unit 40 so as to start discharging the processing liquid.

Next, the control device 100 executes steps S16, S17, and S18. In step S16, for example, the liquid treatment control unit 114 waits until a predetermined discharge time elapses from the discharge start time of the treatment liquid. In step S17, for example, the liquid processing control unit 114 controls the processing liquid supply unit 40 so as to stop the discharge of the processing liquid. In step S18, for example, the liquid processing control unit 114 controls the rotation holding unit 30 to rotate the work W so that the work W rotates at the set value of the rotation speed after the treatment liquid is supplied. Adjust. The set value of the rotation speed is defined in the processing information stored in the processing information storage unit 112.

Next, the control device 100 executes steps S19 and S20. In step S19, for example, the liquid treatment control unit 114 waits until a predetermined drying time elapses from the discharge stop time of the treatment liquid. In step S20, for example, the liquid treatment control unit 114 controls the rotation holding unit 30 so as to stop the rotation of the work W. By executing the above steps S19 and S20, the work W in the state where the treatment liquid is supplied is rotated for a predetermined drying time, and the treatment liquid is applied onto the surface Wa of the work W while rotating. Membrane AF is formed. The period during which the work W is rotated by this drying time corresponds to the rotation period during which the work W is rotated after the treatment liquid is supplied.

Next, the control device 100 executes step S21. In step S21, for example, the film thickness estimation unit 120 controls the measurement unit 60 so as to stop the measurement of the intensity of the reflected wave. In one example, the light projection control unit 122 controls the light emitting and receiving devices 70A to 70C so as to stop the irradiation of the laser light toward the irradiation points P1 to P3, respectively. Then, the signal acquisition unit 124 stops acquiring the intensity of the reflected light accompanying the irradiation of the laser beam. By executing the above processes up to step S21, a signal waveform (time change in the intensity of the reflected wave) as shown in FIG. 9 is acquired for each of the irradiation points P1 to P3.

In the graph of the signal waveform shown in FIG. 9, the timing of receiving the processing start command from the host controller is indicated by "0", and the timing of stopping the discharge of the processing liquid (timing of the start of the drying time) is "t1". It is shown and the measurement time point corresponding to the end timing of the drying time is indicated by "MT". As shown in FIG. 9, after the time t1, the peak portion and the valley portion are formed according to the time change of the interference state between the light L1 reflected by the surface Wa and the light L2 reflected by the outer surface Fa of the coating film AF. A signal waveform in which is repeated is obtained. In FIG. 9, the apex of the mountain portion is drawn with a black circle mark, and the lowest point of the valley portion is drawn with a white circle mark. Further, the signal waveform before the time t1 is omitted.

After executing step S21, the control device 100 executes step S22. In step S22, for example, the film thickness calculation unit 128 between the measurement time point MT and the time point when the signal waveform satisfies a predetermined condition before the measurement time point MT among the signal waveforms obtained up to the execution of step S21. The thickness of the coating film AF at the measurement time point MT is calculated based on the waveform of. More specifically, the feature amount acquisition unit 126 acquires the feature amount from the waveform between the measurement time point MT and the time point where the signal waveform satisfies a predetermined condition before the measurement time point MT among the above signal waveforms. Then, the film thickness calculation unit 128 calculates the thickness of the coating film AF at the measurement time point MT based on the above feature amount.

The feature amount obtained from a part of the signal waveform is, for example, the time of the extreme point appearing at the nth position (n is an integer of 1 or more) counted from the MT at the time of measurement. That is, the feature amount acquisition unit 126 is concerned with the waveform between the measurement time point MT and the time point at which the signal waveform satisfies the condition of the nth extremum point counted in the direction in which the time returns from the measurement time point MT. The time of the nth extremum point of the waveform is acquired as a feature quantity. In the present disclosure, the extreme point is a general term for the apex (maximum point) of the mountain portion and the lowest point (minimum point) of the valley portion.

In the graph of the signal waveform exemplified in FIG. 9, the time of the tenth extreme point (the apex of the fifth mountain portion counted from the measurement time MT) counted from the measurement time point MT is acquired as the feature amount F1. Has been done. In the signal waveform graph of FIG. 9, the ninth extreme value point appearing from the measurement time point MT is the lowest point of the fifth valley portion counting from the measurement time point MT. The feature amount F1 corresponds to the time between the reference timing of liquid processing (for example, the timing when the processing start command is received from the above-mentioned host controller) and the nth extreme value point counted from the measurement time point MT. ..

The film thickness calculation unit 128 calculates the thickness of the coating film AF at the measurement time point MT based on the feature amount F1 by utilizing the correlation between the feature amount F1 and the thickness of the coating film AF. The method of calculating the thickness of the coating film AF using the correlation will be described later. The film thickness calculation unit 128 calculates, for example, the thickness of the coating film AF at each irradiation position based on the signal waveform for each of the irradiation points P1 to P3.

With the above, a series of processes for performing liquid treatment and estimating the film thickness for one work W is completed. The control device 100 may sequentially execute the same series of processes for the plurality of subsequent work Ws. In this case, the control device 100 starts and starts measuring the timing of starting and stopping the discharge of the processing liquid, the drying time for rotating the work W after the treatment liquid is supplied, and the intensity of the reflected light among the plurality of work Ws. A series of processes may be repeatedly executed so that the stop timing is constant. Before executing the above series of processes on the work W, a model formula for estimating the thickness of the coating film AF is constructed.

(How to build a model formula)
FIG. 10 is a flowchart showing an example of a method for constructing a model formula for estimating the thickness of the coating film AF based on the feature amount. In the construction method of this model formula, the rotation speed of the test work WT is changed to a plurality of stages to form the coating film AF, and the feature amount is acquired and the thickness of the coating film AF is measured for each stage. .. Then, a model formula showing the relationship between the feature amount and the estimated value of the thickness of the coating film AF is constructed. In the following, a case where the time of the extreme value point (the above-mentioned feature amount F1) that appears at the nth position from the measurement time point MT is used as the feature amount will be illustrated. The test work WT is a substrate of the same type as the work W.

In this model formula construction method, first, the control device 100 executes step S31. In step S31, for example, the model building unit 134 sets the rotation speed of the test work WT to the initial value. More specifically, the model building unit 134 sets the rotation speed when rotating the test work WT after the treatment liquid is supplied to an initial value (rotation speed of any of a plurality of stages to be changed). The range in which the rotation speed is changed and the range of change per rotation are predetermined by an operator or the like. The range for changing the rotation speed (difference between the maximum rotation speed and the minimum rotation speed) is, for example, 80 rpm to 300 rpm, and the change width per time is 5 rpm to 50 rpm.

Next, the control device 100 executes steps S32 and S33. In step S32, for example, the control device 100 executes the liquid processing and acquires the signal waveform in the same manner as in steps S11 to S21 described above. In step S32, the liquid processing and the signal waveform are processed under the same conditions as those in steps S11 to S21 described above, except that the test work WT is used and the rotation speed of the work when forming the coating film AF. Acquisition is done. In step S33, for example, the model building unit 134 acquires the feature amount F1 from the signal waveform obtained in step S32.

Next, the control device 100 executes step S34. In step S34, for example, the model building unit 134 acquires a measured value indicating the thickness of the coating film AF formed on the surface of the test work WT in step S32. The measured value of the thickness of the coating film AF may be a value measured by any method (using a film thickness measuring device of any method) other than the method of calculating the film thickness based on the signal waveform. The measured value of the thickness of the coating film AF may be, for example, the film thickness measured based on the spectral spectrum obtained by splitting the reflected light from the coating film AF after the rotation is stopped.

Next, the control device 100 executes step S35. In step S35, for example, the model building unit 134 determines whether or not the acquisition of the measured values of the feature amount F1 and the film thickness is completed at all the rotation speeds to be changed. If it is determined in step S35 that the acquisition of the feature amount F1 and the measured values of the film thickness has not been completed at all the rotation speeds (step S35: NO), the control device 100 executes step S36. In step S36, for example, the model building unit 134 changes the set value of the rotation speed of the test work WT. Then, the control device 100 repeats the processes of steps S32 to S35. As a result, the model building unit 134 acquires the feature amount F1 and the measured value of the film thickness for each rotation speed that is changed stepwise.

When the processes of steps S32 to S35 are repeated, the set value of the rotation speed of the work W is set to at least the first rotation speed and the second rotation speed different from the first rotation speed. In this case, the model building unit 134 has the feature amount F1 (first) at the first rotation speed based on the signal waveform obtained while rotating the test work WT (first test substrate) at the first rotation speed. 1 feature amount) is acquired. The model building unit 134 is based on the signal waveform obtained while rotating the test work WT (second test substrate) at the second rotation speed, and the feature amount F1 (second feature amount) at the second rotation speed is used. ).

The model building unit 134 acquires a measured value (first measured value) indicating the thickness of the coating film AF formed on the test work WT when rotated at the first rotation speed. , The model building unit 134 acquires a measured value (second measured value) indicating the thickness of the coating film AF formed on the test work WT when rotated at the second rotation speed. The test work WTs to be rotated at each of the plurality of rotation speeds may be different workpieces or the same workpieces. When the same work is used, the coating film AF may be removed by a chemical solution or the like after the coating film AF is formed and the film thickness is measured.

When it is determined in step S35 that the acquisition of the feature amount F1 and the measured values of the film thickness is completed at all the rotation speeds (step S35: YES), the control device 100 executes step S37. In step S37, for example, the model building unit 134 estimates the film thickness from the feature amount F1 based on the plurality of feature amounts F1 obtained by repeating steps S32 to S35 and the measured values of the plurality of film thicknesses. Generate a model formula to do so. In one example, when the estimated value of the film thickness is "Th", the model building unit 134 generates a linear expression represented by the following equation (1) as a model equation. In the formula (1), "a" and "b" are coefficients, and a model formula is constructed by defining these coefficients.
Th = a × F1 + b (1)

The model construction unit 134 stores the generated (constructed) model formula in the model information storage unit 132. After the construction of the above model formula is completed, the above-mentioned processes of steps S11 to S22 are executed. In step S22 described above, the film thickness calculation unit 128 corresponds to the feature amount F1 obtained during the execution of the liquid treatment by referring to the model formula of the formula (1) stored in the model information storage unit 132. Calculate the film thickness. As described above, the film thickness estimation unit 120 estimates the thickness of the coating film AF formed by performing the liquid treatment on the work W.

[Modification example]
(1) The method of irradiating the surface Wa of the work W with laser light is not limited to the above example. The measuring unit 60 may irradiate the surface Wa of the work W with the laser beam via the mirror member. As shown in FIG. 11, the measuring unit 60 includes, for example, a light emitting / receiving device 170 and a mirror member 80. The light emitting / receiving device 170 and the mirror member 80 are arranged side by side along the horizontal direction (the surface Wa of the work W supported by the holding portion 32). The size of the mirror member 80 may be smaller than that of the light emitting / receiving device 170. The light emitting / receiving device 170 is arranged outside the peripheral edge of the work W.

The mirror member 80 is arranged above the work W held by the holding portion 32 (for example, vertically above the irradiation point of the laser beam). The mirror member 80 changes the direction (direction in which the light travels) of the laser beam irradiating the work W by reflecting the light. The mirror member 80 has, for example, a reflecting surface 82 facing the light emitting / receiving device 170 and the surface Wa of the work W held by the holding portion 32. The light emitting and receiving device 170 irradiates a laser beam that can pass through the coating film AF, similarly to the light emitting and receiving devices 70A to 70C. The light emitting / receiving device 170 (light emitting unit) irradiates a laser beam toward the reflecting surface 82 of the mirror member 80. As a result, the laser beam emitted from the light emitting / receiving device 170 is reflected by the reflecting surface 82 of the mirror member 80 and then irradiated to the surface Wa of the work W.

The light emitting / receiving device 170 (light receiving unit) receives the reflected light of the laser light in the work W through the reflecting surface 82 of the mirror member 80. Similar to the light emitting / receiving devices 70A to 70C, the measuring unit 60 may have a plurality of sets of light receiving / receiving devices 170 and a mirror member 80 in order to irradiate a plurality of different locations with laser light.

(2) The light source of the laser beam may be provided on the inner wall of the housing forming a space for performing the liquid treatment so that the heat does not affect the liquid treatment. As shown in FIG. 11, the liquid treatment unit U1 has a housing 28 that accommodates the rotation holding portion 30 and forms an internal space S for processing the work W with the treatment liquid. The light emitting / receiving device 170 may include a light source 172 that generates a laser beam inside the light emitting / receiving device 170. The light emitting / receiving device 170 (light source 172) may be provided on the inner wall (for example, the inner surface of the side wall) of the housing 28.

(3) The light source of the laser beam may be arranged outside the housing that forms a space for liquid treatment so that the heat does not affect the heat treatment. As shown in FIG. 12, the measuring unit 60 may include a light emitting device 180 (light emitting unit) and a light receiving device 190 (light receiving unit). The light projecting device 180 includes a light source 182, a light guide unit 184, and an irradiation unit 186. The light source 182 generates a laser beam that irradiates the surface Wa of the work W. The light source 182 is arranged outside the housing 28. The light guide unit 184 guides the laser beam from the light source 182 to the inside of the housing 28. The light guide unit 184 is, for example, an optical fiber. The irradiation unit 186 irradiates the surface Wa of the work W with the laser beam guided by the light guide unit 184 via the mirror member.

The light receiving device 190 includes a light collecting unit 192, a light guide unit 194, and a detection unit 196. The reflected light from the work W accompanying the irradiation of the laser beam is incident on the light collecting unit 192 via the mirror member. The light guide unit 194 guides the reflected light incident on the light collecting unit 192 to the detection unit 196 arranged outside the housing 28. The light guide unit 194 is, for example, an optical fiber. The detection unit 196 generates an electric signal corresponding to the reflected light guided by the light guide unit 194. Similar to the light emitting and receiving devices 70A to 70C, the measuring unit 60 may have a plurality of sets of the light emitting and receiving devices 180 and the light receiving device 190 in order to irradiate the laser beam to each of a plurality of different points.

(4) When the measuring unit 60 uses a mirror member, the mirror member may have a film that suppresses scattering and absorption of light. As shown in FIG. 12, the measuring unit 60 may have a mirror member 80A. The mirror member 80A reflects the irradiated laser light toward the surface Wa of the work W, and reflects the reflected light from the work W toward the light receiving device 190. A film 84 that suppresses scattering and absorption of incident laser light on the reflecting surface 82 is formed on the reflecting surface 82 of the mirror member 80A.

(5) The measuring unit 60 may have a member that adjusts the light receiving state of the reflected light according to the positional deviation of the reflected point of the laser light in the work W in the vertical direction. As shown in FIG. 12, the light receiving device 190 of the measuring unit 60 may have an adjusting member 198 that adjusts the light receiving state of the reflected light. The adjusting member 198 adjusts the light receiving state of the reflected light in the light receiving device 190 according to the vertical positional deviation of the work W or the warp of the work W. The adjusting member 198 is provided in, for example, the light collecting unit 192.

The adjusting member 198 reflects the work W so that the intensity of the reflected light received by the light receiving device 190 is about the same as the intensity of the reflected light when the work W has no warp or the like even if the work W has a warp or the like. Adjust the light reception state. The adjusting member 198 is, for example, an optical component that adjusts the optical path of the reflected light or the focal point of the reflected light as the light receiving state of the reflected light.

(6) The surface Wa of the work W may be irradiated with laser light from an oblique direction. As shown in FIG. 13A, the measuring unit 60 may include a light emitting device 280 (light emitting unit) and a light receiving device 290 (light receiving unit). The light emitting device 280 and the light receiving device 290 are arranged along the horizontal direction so as to sandwich the work W between them. The light emitting device 280 and the light receiving device 290 are located outside the peripheral edge of the work W. The light projecting device 280 irradiates the laser beam toward a predetermined irradiation point from a direction inclined with respect to a direction (vertical direction) perpendicular to the surface Wa of the work W. The light receiving device 290 receives the reflected light reflected in the direction inclined with respect to the direction perpendicular to the surface Wa of the work W (vertical direction).

Similar to the light emitting and receiving devices 70A to 70C, the measuring unit 60 may have a plurality of light emitting devices 280 that irradiate laser light toward each of a plurality of different points. In this case, the measuring unit 60 may have a plurality of light receiving devices 290 corresponding to each of the plurality of floodlight devices 280. Instead of the light projecting device 280, a light projecting / light receiving device that functions as a light projecting unit and a light receiving unit may be arranged at a position where the light projecting device 280 is arranged. A mirror member may be arranged in place of the light receiving device 290 at a position where the light receiving device 290 is arranged. In this case, the light emitting / receiving device irradiates the surface Wa of the work W with laser light from an oblique direction, and the reflected light from the work W is reflected by the mirror member toward the light receiving / receiving device.

(7) When irradiating each of a plurality of locations with laser light, the laser beam generated from one light source is the light emitted to one location and the light emitted to a location different from the one location. It may be divided into and. As shown in FIG. 13B, the measuring unit 60 may have a light projecting device 280A and a plurality (three) light receiving devices 290. The floodlight device 280A includes one light source 282, a branch portion 284, and a plurality of light guide portions 286. The light source 282 generates a laser beam that is emitted toward the surface Wa of the work W.

The branch portion 284 divides the laser light from the light source 282 into the laser light emitted toward each of a plurality of locations. For example, the branching portion 284 branches the laser light from the light source 282 into a light that irradiates any one of the plurality of locations and a light that irradiates the other one of the plurality of locations. The branch portion 284 is composed of an optical component such as a beam splitter. The plurality of laser beams branched by the branch portion 284 may be incident on each of the plurality of light guide portions 286. The light guide unit 286 is, for example, an optical fiber. The light projecting device 280A irradiates the laser light guided by the plurality of light guide units 286 toward a plurality of locations overlapping the surface Wa of the work W. The branch portion 284 may divide the light from one light source so as to go to a different place at each time. For example, the branch portion 284 may be configured by a MEMS (Micro-Electro-Mechanical Systems) mirror having a function of changing the angle of the reflecting surface (mirror surface) by swinging.

(8) In the above example, the laser beam is irradiated to three places overlapping the surface Wa of the work W, but the laser light may be irradiated to one place overlapping the surface Wa of the work W. In this case, the film thickness estimation unit 120 of the control device 100 may estimate the thickness of the coating film AF at the one point irradiated with the laser beam. The irradiation points of the laser beam (estimated points of the thickness of the coating film AF) may be two places or four or more places. When the film thickness is estimated at a plurality of locations, unlike the above example, the distances between these locations and the center CP of the work W may be substantially the same as each other.

(9) The optical path of the laser light and the reflected light in the measuring unit 60 may be adjusted by using another laser light for adjustment. The adjustment of the optical path using another laser beam may be performed by an operator or the like before the liquid treatment is performed.

(10) The intensity of the laser beam applied to the work W may be adjusted according to the intensity of the reflected light received by the measuring unit 60 (for example, the average intensity). As shown in FIG. 6, the control device 100 (film thickness estimation unit 120) may have a light projection condition setting unit 138 (condition setting unit) as a functional module. The light projection condition setting unit 138 changes the setting value of the light intensity from the light projection unit such as the light emitting / receiving devices 70A to 70C based on the comparison result between the intensity of the reflected light and a predetermined threshold value. For example, the light projecting condition setting unit 138 increases the setting value of the intensity of the laser light emitted from the light projecting unit when the average intensity of the reflected light falls below a predetermined threshold value.

When the set value of the laser light intensity is changed by the light projecting condition setting unit 138, the light projecting control unit 122 controls the measuring unit 60 so that the laser light having the changed intensity of the set value is irradiated. do. The light projection condition setting unit 138 may acquire the intensity of the reflected light for changing the set value of the irradiation intensity of the laser light for each execution of one or a plurality of liquid treatments. The floodlight condition setting unit 138 changes the set value of the laser beam irradiation intensity after forming the coating film AF on the test work W during the period when the liquid treatment on the work W is not executed. The intensity of the reflected light may be obtained.

(11) The control device 100 may change the liquid treatment conditions for the subsequent work W according to the film thickness calculated by the film thickness calculation unit 128. The control device 100 (film thickness estimation unit 120) may have a processing condition changing unit 136 as a functional module. The processing condition changing unit 136 sets values of various conditions for liquid processing included in the processing information stored in the processing information storage unit 112 based on the thickness of the coating film AF calculated by the film thickness calculation unit 128. change. For example, in the processing condition changing unit 136, when the absolute value of the difference between the average value of the thickness of the coating film AF calculated for the irradiation points P1 to P3 and the predetermined target thickness is larger than the predetermined value. , The set value of the rotation speed of the work W after the treatment liquid is supplied is changed so that the difference is reduced.

(12) As described above, among the signal waveforms based on the received reflected light, the feature amount obtained from the waveform between the measurement time point MT and the time point where the signal waveform satisfies a predetermined condition before the measurement time point MT. Based on this, the thickness of the coating film AF at the measurement time point MT is calculated. In the above example, the time of the nth extreme value point counted from the measurement time point MT is used as the feature amount F1, but the coating film AF at the measurement time point MT is based on a feature amount different from the feature amount F1. The thickness of may be calculated. Hereinafter, some feature quantities will be illustrated.

(12-1) The feature amount obtained from a part of the signal waveform may be the time from the last time point when the signal waveform intensity matches the preset base intensity to the measurement time point MT. The feature amount acquisition unit 126 is the time between the measurement time point MT and the coincidence point from the waveform between the measurement time point MT and the time point satisfying the condition that the intensity of the signal waveform finally matches the predetermined base strength. Is acquired as the feature amount F2. Even when the feature amount F2 is used, a model formula showing the relationship between the thickness of the coating film AF and the feature amount F2 is constructed.

FIG. 14 shows a graph of the signal waveform acquired while forming the coating film AF on the test work WT by changing the rotation speed in five steps. In the graph of the signal waveform of FIG. 14, the waveform of only the latter half of the signal waveform (near the end of the rotation time) is shown. The changed rotation speed values are indicated by "ω1" to "ω5", respectively, and the values increase in the order of ω1 to ω5. The above-mentioned base strength is indicated by "BI", and the base strength BI is, for example, at the measurement time point MT of the signal waveform obtained from the coating film AF formed at the lowest rotation speed when creating a model formula. Corresponds to strength. The base strength BI may be set to the strength at the measurement time point MT of the signal waveform obtained from the coating film AF formed at the maximum rotation speed.

For example, when the rotation speed is ω5, the time between the time t5 at the point where the intensity of the signal waveform for the rotation speed finally matches the base intensity BI and the measurement time point MT is acquired as the feature amount F2. Will be done. The model building unit 134 generates a model formula for estimating the film thickness from the feature amount F2 based on the plurality of feature amounts F2 obtained by changing the rotation speed in five steps and the measured values of the plurality of film thicknesses. do. In one example, the model building unit 134 generates a quadratic formula represented by the following formula (2) as a model formula for defining the relationship between the estimated film thickness Th and the feature amount F2. In the equation (2), "a1", "b1" and "c1" are coefficients, and a model equation is constructed by defining these coefficients.
Th = a1 x F2 x F2 + b1 x F2 + c1 (2)

The film thickness calculation unit 128 calculates the film thickness according to the feature amount F2 obtained during the execution of the liquid treatment by referring to the constructed model formula. The model building unit 134 may generate a model formula by using a polynomial approximation of degree 3 or higher. Which approximate formula to use for the model formula may be selected for each feature amount after the correlation between the measured value of the film thickness and the feature amount is evaluated.

(12-2) The feature quantity obtained from a part of the signal waveform is the intensity of the signal waveform at the extreme value point (maximum or minimum point) that appears first from the measurement time MT and the measurement time MT. It may be a value obtained by dividing the difference from the intensity of the signal waveform in (1) by the intensity of the signal waveform at the first extremum point. FIG. 15A shows the waveform of the latter half of the signal waveform (near the end of the rotation period).

The feature amount acquisition unit 126 is the first waveform from the waveform between the measurement time point MT and the time point at which the signal waveform satisfies the condition of becoming the first extreme value point counting in the direction in which the time returns from the measurement time point MT. The signal waveform intensity In1 at the extreme point of the measurement and the signal waveform intensity In2 at the measurement time point MT are acquired. Then, the feature amount acquisition unit 126 obtains a value obtained by subtracting the intensity In1 from the intensity In2, and calculates the value obtained by dividing the obtained value by the intensity In1 as the feature amount F3. Similar to the case where the feature amounts F1 and F2 are used, the film thickness estimation unit 120 constructs a model formula for the feature amount F3, and by referring to the model formula, the feature amount acquired in the liquid treatment to the work W. The thickness of the coating film AF is calculated (estimated) according to F3.

(12-3) The feature quantity obtained from a part of the signal waveform is the phase according to the intensity of the signal waveform at the extreme value point that appears first from the measurement time MT, and the signal waveform at the measurement time MT. It may be the difference from the phase according to the intensity of. FIG. 15 (b) shows a waveform obtained by converting the time change of the intensity in a part of the latter half of the signal waveform (the period indicated by “LP” in FIG. 15 (a)) into the time change of the phase. .. In the conversion from intensity to phase, the phase of the point of the signal waveform where the intensity is maximum is π / 2, and the phase of the point of the signal waveform where the intensity is minimum is (-π / 2). Then, an operation using an inverse sine function (arc sine) is performed. For example, in an operation using an inverse sine function, the strength of the signal waveform is first normalized. Specifically, normalization is performed so that the maximum value of the intensity of the signal waveform is 1 and the minimum value of the intensity is -1. Then, by calculating the inverse sine function with the normalized intensity as a variable, the conversion from the intensity to the phase is performed.

The feature amount acquisition unit 126 acquires, for example, the intensity In1 of the signal waveform at the first extreme point and the intensity In2 of the signal waveform at the time of measurement. Then, the feature amount acquisition unit 126 converts the intensity In1 into the phase Ph1 and converts the intensity In2 into the phase Ph2 by performing an operation using the inverse sine function. After that, the feature amount acquisition unit 126 calculates the value obtained by subtracting the phase Ph1 from the phase Ph2 as the feature amount F4. Similar to the case where the feature amounts F1 and F2 are used, the film thickness estimation unit 120 constructs a model formula for the feature amount F4, and by referring to the model formula, the feature amount acquired in the liquid treatment to the work W. The thickness of the coating film AF is calculated (estimated) according to F4.

(12-4) The feature amount obtained from a part of the signal waveform may be the difference between the preset base intensity BI and the intensity of the signal waveform at the measurement time point MT. The base intensity BI is determined at the measurement time point MT of the signal waveform obtained from the coating film AF formed at the smallest rotation speed or the largest rotation speed when the model formula is created, as in the case where the feature amount F2 is used. It may be strong. FIG. 16 shows a plurality of signal waveforms obtained when creating a model formula.

In this example, the difference between the base intensity BI and the intensity Inm of the signal waveform at the measurement time point MT is acquired as the feature amount F5. That is, the feature amount acquisition unit 126 acquires the difference between the base intensity BI and the intensity Inm (a value obtained by subtracting the base intensity BI from the intensity Innm) as the feature amount F5 from the waveform at the measurement time point MT. As described above, in the present disclosure, among the signal waveforms, the waveform (information) between the measurement time point MT and the time point in which the signal waveform satisfies a predetermined condition before the measurement time point MT may be determined depending on the above-mentioned predetermined conditions. , The waveform (information) at the measurement time point MT is also included. Similar to the case where the feature amounts F1 and F2 are used, the film thickness estimation unit 120 constructs a model formula for the feature amount F5, and by referring to the model formula, the feature amount acquired in the liquid treatment to the work W. The thickness of the coating film AF is calculated (estimated) according to F5.

(12-5) The feature amount obtained from a part of the signal waveform may be the difference between the phase corresponding to the preset base intensity BI and the phase corresponding to the intensity of the signal waveform at the measurement time point MT. good. The base intensity BI is determined at the measurement time point MT of the signal waveform obtained from the coating film AF formed at the smallest rotation speed or the largest rotation speed when the model formula is created, as in the case where the feature amount F2 is used. It may be strong.

The feature amount acquisition unit 126 acquires the intensity Inm of the signal waveform at the measurement time point MT from the waveform at the measurement time point MT. Then, the feature amount acquisition unit 126 converts the base intensity BI into the phase and the intensity Inm into the phase by performing an operation using the inverse sine function, as in the case where the feature amount F4 is used. After that, the feature amount acquisition unit 126 calculates a value obtained by subtracting the phase corresponding to the base intensity BI from the phase corresponding to the intensity Inm as the feature amount F6. Similar to the case where the feature amounts F1 and F2 are used, the film thickness estimation unit 120 constructs a model formula for the feature amount F6, and by referring to the model formula, the feature amount acquired in the liquid treatment to the work W. The thickness of the coating film AF is calculated (estimated) according to F6.

(12-6) The feature amount acquisition unit 126 is based on the above-mentioned feature from the waveform (information) between the measurement time point MT and the time point where the signal waveform satisfies a predetermined condition before the measurement time point MT among the signal waveforms. Feature quantities other than the quantities F1 to F6 may be acquired. Any feature amount may be used as long as a correlation can be obtained with the thickness of the coating film AF.

(13) In the above example, the thickness of the coating film AF of the treatment liquid (resist) for forming the resist film is estimated, but the film thickness estimation unit 120 is a film other than the resist film (for example, a lower layer). The thickness of the coating film of the treatment liquid for forming the film or the upper layer film) may be estimated. The film thickness estimation unit 120 may estimate the thickness of the developer film for developing the resist film.

(14) In the above example, the measurement time point MT is set at the end time point of the rotation period (drying time), but it may be set at any time point before the end time point. In this case, the film thickness estimation unit 120 may construct a model formula showing the relationship between the film thickness and the feature amount at the time point when the measurement time point MT is set.

(15) The above-mentioned series of processing executed by the control device 100 in the substrate processing method (film thickness estimation method) and the model formula construction method is an example, and can be appropriately changed. For example, some of the steps (processes) described above may be omitted, or the steps may be executed in a different order. Further, any two or more steps among the above-mentioned steps may be combined, or a part of the steps may be modified or deleted. Alternatively, other steps may be performed in addition to each of the above steps.

[Effect of embodiment]
The substrate processing system 1 described above rotates the work W in a state where the treatment liquid is supplied on the surface Wa so that a film of the treatment liquid (coating film AF) is formed on the surface Wa of the work W. The liquid treatment unit U1 configured to cause the light and the light projection configured to irradiate the portion overlapping the surface Wa of the work W during the rotation period in which the liquid treatment unit U1 rotates the work W. It is configured to receive the reflected light obtained by combining the light emitted through the coating film AF after reflecting the surface Wa of the work W and the light reflected by the outer surface Fa of the coating film AF. It includes a light receiving unit, a liquid processing unit U1, a light projecting unit, and a control device 100 that controls the light receiving unit. The control device 100 acquires a signal acquisition unit 124 configured to acquire a signal waveform indicating a time change in the intensity of the reflected light during the rotation period based on the reflected light received by the light receiving unit, and a signal acquisition unit 124. The thickness of the coating film AF at the measurement time point MT based on the waveform between the predetermined measurement time point MT within the rotation period and the time point where the signal waveform satisfies the predetermined condition before the measurement time point MT. It has a film thickness calculation unit 128 configured to calculate the signal.

In the substrate processing method described above, the work W in a state where the treatment liquid is supplied on the surface Wa is rotated so that the coating film AF is formed on the surface Wa of the work W, and the work W is formed. During the rotating period, the light is irradiated toward the portion overlapping the surface Wa of the work W, the light emitted through the coating film AF after reflecting the surface Wa of the work W, and the coating film AF. Receiving the reflected light combined with the light reflected by the outer surface Fa of the above, acquiring the signal waveform showing the time change of the intensity of the reflected light during the rotation period based on the received reflected light, and the signal The thickness of the processing liquid film at the measurement time point MT based on the waveform between the predetermined measurement time point MT within the rotation period and the time point when the signal waveform satisfies the predetermined condition before the measurement time point MT. Includes calculating.

In the substrate processing system 1 and the substrate processing method, the reflected light is a combination of the light emitted through the coating film AF after reflecting the surface Wa of the work W and the light reflected by the outer surface Fa of the coating film AF. A signal waveform indicating the time change of the intensity of is acquired. Depending on the thickness of the coating film AF during rotation, the light emitted through the coating film AF after reflecting the surface Wa of the work W and the light reflected by the outer surface Fa of the coating film AF Since the interference state of is changed, the signal waveform contains information regarding the thickness of the coating film AF. Therefore, it is possible to calculate (estimate) the coating film AF from the waveform between the predetermined measurement time point MT within the rotation period and the time point when the signal waveform satisfies the predetermined condition before the measurement time point MT among the signal waveforms. can. In the substrate processing system 1 and the substrate processing method, the thickness of the coating film AF is calculated from the time change of the intensity of the reflected light. Therefore, even if the thickness of the coating film AF fluctuates, the coating film AF is calculated. It is possible to estimate the AF thickness with high accuracy. For example, since the feature amount is based on the relative time change of the signal waveform, it is not easily affected by noise generated by various factors when detecting the reflected light. Therefore, it is possible to improve the estimation accuracy by estimating the film thickness based on the feature amount.

The control device 100 is a feature amount acquisition unit configured to acquire a feature amount from a waveform between a measurement time point MT and a time point in which the signal waveform satisfies a predetermined condition before the measurement time point MT among the signal waveforms. 126 may be further included. The film thickness calculation unit 128 may be configured to calculate the thickness of the coating film AF at the measurement time point MT based on the feature amount acquired by the feature amount acquisition unit 126. Since the signal waveform contains information about the thickness of the coating film AF, the feature amount obtained from a part of the waveform can correlate with the thickness of the coating film AF. Therefore, by utilizing the correlation between the feature amount and the thickness of the coating film AF, the calculation for calculating the thickness of the coating film AF is simplified.

The light projecting unit irradiates light toward the above-mentioned portion (for example, the irradiation portion P1) and another portion (for example, the irradiation portion P2) that overlaps the surface Wa of the work W at a position different from the location. It may be configured in. In this case, by further acquiring the signal waveform based on the reflected light from another location, it is possible to estimate the thickness of the coating film AF at a plurality of locations. For example, by estimating the thickness of the coating film AF at a plurality of locations, the thickness of the coating film AF can be evaluated by an average value.

The distance between the above-mentioned place and the center CP of the work W and the distance between the above-mentioned other place and the center CP of the work W may be different from each other. In this case, it is possible to estimate the film thickness at positions where the distances from the center CP of the work W are different from each other. For example, by estimating the film thickness at different distances from the central CP, it is possible to improve the accuracy of the evaluation of the film thickness at the average value.

The liquid treatment unit U1 may have a holding portion 32 that supports the work W. The above-mentioned portion (for example, the irradiation portion P1) may be set so as to overlap with the holding portion 32. The thickness of the portion of the coating film AF corresponding to the holding portion 32 may be affected by the holding portion 32. In the above configuration, since the film thickness at the portion affected by the holding portion 32 is estimated, it is possible to evaluate the film thickness after taking the relevant portion into consideration.

The light projecting unit is configured to irradiate the above-mentioned part with light having a predetermined frequency and to irradiate the above-mentioned other part with another light having a frequency different from the frequency of the light irradiating the part. You may. In this configuration, even when a part of the reflected light from another place is received by the light receiving portion, it is easy to remove the influence of a part of the reflected light from another place from the signal waveform. For example, when two lights with different frequencies are mixed in the light received by one light receiving unit, one of the reflected light from another place is obtained by removing components other than the frequency to be received by the light receiving unit. The influence of the part can be removed.

The light projecting unit is configured to divide the light from one light source 282 that generates the light to irradiate the work W and the light from the light source 282 into the light radiated to the above-mentioned portion and the light radiated to the other portion. It may have a branch portion 284 and the branch portion 284. In this case, when the film thickness is estimated by irradiating a plurality of places with light, the number of light sources can be reduced, and the apparatus can be simplified.

The liquid treatment unit U1 may have a housing 28 that forms an internal space S for performing liquid treatment using the treatment liquid on the work W. The light projecting unit may have a light source that generates light to irradiate the work W. When the light source is placed near the work W, the film thickness may fluctuate due to the heat of the light source. On the other hand, in the above configuration, since the light source and the work W to which the liquid treatment is applied can be separated from each other, it is possible to reduce the influence of the heat of the light source on the liquid treatment.

The light projecting unit may have

mirror members

80, 80A configured to change the direction of the light applied to the work W by reflecting the light. When the member is arranged vertically above the work W, it affects the air flow above the substrate and the film thickness may fluctuate. On the other hand, in the above configuration, since the portion included in the light projecting unit to be irradiated with light can be arranged away from the work W, it is possible to reduce the influence of the light projecting unit on the liquid treatment.

The reflecting surface 82 of the mirror member 80A may be formed with a film 84 configured to suppress scattering and absorption of incident light on the reflecting surface 82. In this case, it is possible to suppress a decrease in the amount of light received by the light receiving unit while reducing noise contained in the light received by the light receiving unit. As a result, it becomes possible to estimate the film thickness with higher accuracy based on the signal waveform.

The substrate processing system 1 may further include an adjusting member 198 configured to adjust the light receiving state of the reflected light in the light receiving portion according to the vertical positional deviation of the work W or the warp of the work W. In this case, even if the effect of the vertical displacement of the work W or the warp of the work W is added to the reflected light, the effect is reduced from the reflected light by the adjusting member before the light receiving portion receives the reflected light. Will be done. As a result, it becomes possible to stabilize the estimation of the film thickness.

The control device 100 further includes a light projection condition setting unit 138 configured to change the set value of the light intensity from the light projector unit based on the comparison result between the intensity of the reflected light and a predetermined threshold value. You may. In this case, when the intensity of the reflected light received by the light receiving unit is lowered, the intensity of the reflected light can be maintained by increasing the set value of the intensity of the light from the light projecting unit. As a result, it is possible to stabilize the estimation of the film thickness even if the light receiving portion may be deteriorated (for example, even if the lens which is an optical component may be fogged).

1 ... Substrate processing system, 2 ... Coating and developing device, 20 ... Film film estimation device, 60 ... Measuring unit, 70A to 70C, 170 ... Projecting and receiving device, 72 ... Projecting unit, 180, 280, 280A ... Projecting device, 74 ... light receiving unit, 190, 290 ... light receiving device, 80, 80A ... mirror member, 82 ... reflective surface, 84 ... film, 100 ... control device, 122 ... light projection control unit, 124 ... signal acquisition unit, 126 ... feature quantity Acquisition unit, 128 ... Film thickness calculation unit, 134 ... Model construction unit, 136 ... Processing condition change unit, 138 ... Light projection condition setting unit, W ... Work, Wa ... Surface, CP ... Center, AF ... Coating film, Fa ... Outer surface, P1 to P3 ... irradiation points, F1 to F6 ... feature quantities.

Claims

A liquid treatment unit configured to rotate the substrate in a state where the treatment liquid is supplied on the surface so that a film of the treatment liquid is formed on the surface of the substrate.
A light projecting unit configured to irradiate light toward a portion overlapping the surface of the substrate during a rotation period in which the liquid processing unit rotates the substrate.
Light receiving light configured to receive reflected light that is a combination of light emitted through the film of the treatment liquid after being reflected on the surface of the substrate and light reflected on the outer surface of the film of the treatment liquid. Department and
A control unit for controlling the liquid treatment unit, the light projection unit, and the light receiving unit is provided.
The control unit
A signal acquisition unit configured to acquire a signal waveform indicating a time change in the intensity of the reflected light during the rotation period based on the reflected light received by the light receiving unit.
The signal waveform acquired by the signal acquisition unit is based on a waveform between a predetermined measurement time point within the rotation period and a time point in which the signal waveform satisfies a predetermined condition before the measurement time point. A substrate processing apparatus having a film thickness calculating unit configured to calculate the film thickness of the processing liquid at the time of measurement.
The control unit is configured to acquire a feature amount from the waveform of the signal waveform between the measurement time point and the time point when the signal waveform satisfies a predetermined condition before the measurement time point. It also has an acquisition unit,
The first aspect of the present invention, wherein the film thickness calculation unit is configured to calculate the film thickness of the treatment liquid at the time of measurement based on the feature amount acquired by the feature amount acquisition unit. Board processing equipment.
2. Board processing equipment.
The substrate processing apparatus according to claim 3, wherein the distance between the location and the center of the substrate and the distance between the other location and the center of the substrate are different from each other.
The liquid treatment unit has a support unit configured to support the substrate, and the liquid treatment unit has a support unit.
The substrate processing apparatus according to claim 3 or 4, wherein the portion is set so as to overlap the support portion.
The light projecting unit is configured to irradiate the portion with light having a predetermined frequency and to irradiate the other portion with another light having a frequency different from the frequency of the light irradiating the portion. The substrate processing apparatus according to any one of claims 3 to 5.
The light projecting unit divides the light from one light source that generates the light to irradiate the substrate and the light from the one light source into the light radiated to the portion and the light radiated to the other portion. The substrate processing apparatus according to any one of claims 3 to 5, further comprising a branch portion configured in.
The liquid treatment unit has a housing that forms an internal space for processing the substrate with the treatment liquid.
The light projecting unit has a light source that generates light to irradiate the substrate.
The substrate processing apparatus according to any one of claims 1 to 6, wherein the light source is provided on the inner wall of the housing or is arranged outside the housing.
The substrate processing apparatus according to any one of claims 1 to 8, wherein the light projecting unit has a mirror member configured to change the direction of light irradiating the substrate by reflecting light.
The substrate processing apparatus according to claim 9, wherein a film configured to suppress scattering and absorption of incident light on the reflecting surface is formed on the reflecting surface of the mirror member.
Any of claims 1 to 10, further comprising an adjusting member configured to adjust the light receiving state of the reflected light in the light receiving portion according to the vertical positional deviation of the substrate or the warp of the board. The substrate processing apparatus according to paragraph 1.
The control unit further includes a condition setting unit configured to change a set value of the intensity of light from the light projecting unit based on a comparison result between the intensity of the reflected light and a predetermined threshold value. Item 6. The substrate processing apparatus according to any one of Items 1 to 11.
The substrate in which the treatment liquid is supplied on the surface is rotated so that a film of the treatment liquid is formed on the surface of the substrate.
During the rotation period during which the substrate is rotated, light is applied to a portion that overlaps the surface of the substrate.
Receiving the reflected light, which is a combination of the light emitted through the film of the treatment liquid after being reflected on the surface of the substrate and the light reflected on the outer surface of the film of the treatment liquid.
To acquire a signal waveform indicating a time change in the intensity of the reflected light during the rotation period based on the received reflected light.
The processing liquid at the measurement time point is based on the waveform of the signal waveform between a predetermined measurement time point within the rotation period and a time point at which the signal waveform satisfies a predetermined condition before the measurement time point. Substrate processing methods, including calculating film thickness.
A computer-readable storage medium in which a program for causing a substrate processing apparatus to execute the substrate processing method according to claim 13 is stored.