WO2021182117A1

WO2021182117A1 - Abnormality detection device, substrate processing device, abnormality detection method, and storage medium

Info

Publication number: WO2021182117A1
Application number: PCT/JP2021/007047
Authority: WO
Inventors: 林　聖人; 耕平野口; 広大東
Original assignee: 東京エレクトロン株式会社
Priority date: 2020-03-09
Filing date: 2021-02-25
Publication date: 2021-09-16
Also published as: JPWO2021182117A1; TW202200988A; JP2024040273A; CN115244387A; KR20220150339A

Abstract

An abnormality detection device comprises: a detection unit having a flow path formation part for forming a treatment-liquid flow path through which flows a treatment liquid supplied to a substrate, and a measurement unit configured so as to receive emitted light that has been emitted from the treatment-liquid flow path due to the treatment-liquid flow path having been irradiated with irradiation light from a light source; an abnormality assessment unit that, on the basis of the signal intensity of the emitted light, assesses whether an abnormality is included in the treatment liquid; and an intensity information acquisition unit that, on the basis of the signal intensity, acquires intensity information indicating the intensity of background light included in the emitted light.

Description

Foreign matter detection device, substrate processing device, foreign matter detection method, and storage medium

The present disclosure relates to a foreign matter detection device, a substrate processing device, a foreign matter detection method, and a storage medium.

Patent Document 1 discloses a detection device for submicron particles existing as an insoluble matter in a fluid. This detection device includes an optical system that collects light from a coherent light source, a cell that is located near the focal point of the light beam focused by this optical system, and a cell through which a flow of fluid containing fine particles passes. By an optical detector arranged on the optical path of the optical beam and on the opposite side of the cell from the light source of the optical beam, and an electric circuit that measures the number of fine particles in the fluid from the electric signal from the optical detector. It is configured.

Japanese Unexamined Patent Publication No. 5-215664

The present disclosure provides a foreign matter detection device, a substrate processing device, a foreign matter detection method, and a storage medium capable of confirming whether or not the state of the device or the treatment liquid is normal.

In the foreign matter detection device according to one exemplary embodiment, the flow path forming portion forming the treatment liquid flow path through which the treatment liquid supplied to the substrate flows, and the treatment liquid flow path are irradiated with the irradiation light from the light source. Based on the detection unit having a measuring unit configured to receive the emitted light emitted from the processing liquid flow path and the signal intensity of the emitted light, whether or not the processing liquid contains foreign matter is determined. A foreign matter determination unit for determination and an intensity information acquisition unit for acquiring intensity information indicating the intensity of the background light included in the emitted light based on the signal intensity are provided.

According to the present disclosure, a foreign matter detecting device, a substrate processing device, a foreign matter detecting method, and a storage medium capable of confirming whether or not the state of the device or the processing liquid is normal are provided.

FIG. 1 is a schematic perspective view 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 view showing an example of the liquid treatment unit. FIG. 4 is a schematic view showing an example of the treatment liquid supply unit of the liquid treatment unit. FIG. 5 is a side view schematically showing an example of the foreign matter detection unit. FIG. 6 is a perspective view schematically showing an example of a foreign matter detection unit. FIG. 7 is a side view schematically showing an example of the foreign matter detection unit. FIG. 8 is a block diagram showing an example of the functional configuration of the control unit. FIG. 9 is a graph showing an example of signal intensity according to the detected light. FIG. 10 is a block diagram showing an example of the hardware configuration of the control unit. FIG. 11 is a flowchart showing an example of a foreign matter detecting method.

Hereinafter, various exemplary embodiments will be described.

In this foreign matter detecting device, in addition to detecting foreign matter based on the emitted light emitted from the processing liquid flow path by the irradiation of the irradiation light, the intensity information of the background light contained in the emitted light is acquired. Since the strength information changes based on the state of the detection unit or the treatment liquid, the foreign matter detection device can confirm whether or not the state of the device or the treatment liquid is normal.

The emitted light may be light in which the irradiation light is scattered in the processing liquid flow path. In this case, since the difference in the intensity of the detected light is large depending on the presence or absence of foreign matter in the treatment liquid, foreign matter can be detected more reliably.

The intensity information acquisition unit may acquire the time average of the signal intensity obtained in a predetermined period as intensity information. Since the intensity of the background light can fluctuate according to the obtained time, it is possible to more reliably confirm the state of the apparatus or the treatment liquid based on the time average.

The foreign matter determination unit may determine whether or not the treatment liquid contains foreign matter during the supply period from the start of supply of the treatment liquid to the substrate to the end of supply. The strength information acquisition unit may acquire strength information based on the signal strength obtained during the supply period. In this case, it is possible to efficiently check the state of the treatment liquid or the detection unit by using the information obtained during the supply period.

Even if the strength information acquisition unit acquires strength information based on the signal strength obtained when the treatment liquid is filled in the treatment liquid flow path and the treatment liquid is not supplied to the substrate. good. In this case, since the disturbance component that may be contained in the background light due to the flow of the treatment liquid can be reduced, the state of the apparatus or the treatment liquid can be confirmed more accurately.

The foreign matter detection device may further include a condition monitoring unit that monitors the status of at least one of the processing liquid and the detection unit based on the strength information. In this case, it is possible to detect foreign matter after confirming the state of the apparatus or the treatment liquid.

The substrate processing apparatus according to one exemplary embodiment has a processing liquid supply unit having a nozzle for discharging the processing liquid toward the substrate, a supply unit for supplying the processing liquid to the nozzle, and a processing liquid flow through which the processing liquid flows. It has a flow path forming unit that forms a path, and a measuring unit that is configured to receive the emitted light emitted from the processing liquid flow path when the treatment liquid flow path is irradiated with the irradiation light from the light source. A detection unit, a foreign matter determination unit that determines whether or not foreign matter is contained in the processing liquid based on the signal intensity of the emitted light, and an intensity indicating the intensity of the background light contained in the emitted light based on the signal intensity. It is provided with a strength information acquisition unit for acquiring information. In this substrate processing apparatus, it is possible to confirm whether or not the state of the apparatus or the processing liquid is normal, as in the case of the foreign matter detecting apparatus described above.

In the foreign matter detection method according to one exemplary embodiment, when the treatment liquid flow path through which the treatment liquid supplied to the substrate flows is irradiated with the irradiation light from the light source, the emitted light emitted from the treatment liquid flow path is emitted. Includes determining whether or not foreign matter is contained in the processing liquid based on the signal intensity, and acquiring intensity information indicating the intensity of the background light contained in the emitted light based on the signal intensity. .. In this foreign matter detecting method, it is possible to confirm whether or not the state of the apparatus or the treatment liquid is normal, similarly to the above-mentioned foreign matter detecting apparatus.

The computer-readable storage medium according to one exemplary embodiment is a storage medium that stores a program for causing the device to execute the above-mentioned foreign matter detection method.

Hereinafter, one embodiment will be described 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. Some drawings show a Cartesian coordinate system defined by the X, Y and Z axes. In the following embodiments, the Z-axis corresponds to the vertical direction and the X-axis and the Y-axis correspond to the horizontal direction.

[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 performing a predetermined process. The substrate included in the work W is, for example, a wafer containing silicon. The work W (board) may be formed in a circular shape. The work W to be processed may be a glass substrate, a mask substrate, an FPD (Flat Panel Display), or the like, or may be an intermediate obtained by subjecting these substrates or the like to a predetermined treatment. The photosensitive film is, for example, a resist film.

The substrate processing system 1 includes a coating / developing device 2 and an exposure device 3. 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 / developing device 2 applies a resist (chemical solution) to the surface of the work W to form a resist film before the exposure process by the exposure device 3, and develops the resist film after the exposure process.

(Board processing equipment)
Hereinafter, the configuration of the coating / developing device 2 will be described as an example of the substrate processing device. As shown in FIGS. 1 and 2, the coating / developing device 2 includes a carrier block 4, a processing block 5, an interface block 6, and a control device 18.

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 includes a transfer device A1 including a delivery 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 a plurality of

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. 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 applies a treatment liquid (resist) for forming a resist film on the lower 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 is subjected to the development treatment of the exposed resist film and the heat treatment associated with the development treatment by the liquid treatment unit U1 and the heat treatment unit U2. 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 (PEB: Post Exposure Bake) before development treatment, heat treatment (PB: Post Bake) after development treatment, 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 on 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 18 controls the coating / developing device 2 so as to execute the coating / developing process in the following procedure, for example. First, the control device 18 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 18 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 18 controls the liquid treatment unit U1 and the heat treatment unit U2 so as to form an underlayer film on the surface of the work W. After that, the control device 18 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 18 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 18 controls the liquid treatment unit U1 and the heat treatment unit U2 so as to form a resist film on the surface of the work W. After that, the control device 18 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 18 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 18 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 18 controls the transfer device A3 so as to transfer the work W to the shelf unit U11.

Next, the control device 18 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 18 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 18 controls the transport device A3 so as to transport 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 18 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 / developing process for one piece of work W. The control device 18 causes the coating / developing device 2 to execute the coating / developing process for each of the subsequent plurality of workpieces W.

(Liquid processing unit)
Subsequently, an example of the liquid treatment unit U1 will be described in detail with reference to FIGS. 3 and 4. Here, the liquid treatment unit U1 in the treatment module 12 for forming the resist film will be described as an example. As shown in FIG. 3, the liquid treatment unit U1 has a rotation holding unit 20 and a processing liquid supply unit 30.

The rotation holding unit 20 holds and rotates the work W based on the operation instruction of the control device 18. The rotation holding unit 20 has, for example, a holding unit 22 and a rotation driving unit 24. The holding portion 22 supports the central portion of the work W arranged horizontally with the surface Wa facing up, and holds the work W by, for example, vacuum suction. The rotation drive unit 24 is an actuator including a power source such as an electric motor, and rotates the holding unit 22 around the vertical axis Ax. As a result, the work W on the holding portion 22 rotates.

The treatment liquid supply unit 30 supplies the treatment liquid to the surface Wa of the work W by discharging the treatment liquid toward the surface Wa of the work W based on the operation instruction of the control device 18. The treatment liquid supplied by the treatment liquid supply unit 30 is a substrate processing solution used for processing the work W. Examples of the treatment liquid include a solution (resist) used for forming a resist film and a solution (for example, thinner) used for a pre-wet treatment for enhancing the wettability of the surface Wa with respect to the resist. The processing liquid supply unit 30 has, for example, a plurality of nozzles 32, a holding head 34, and a supply unit 36.

The plurality of nozzles 32 each discharge the treatment liquid onto the surface Wa of the work W held by the holding portion 22. The plurality of nozzles 32 are arranged above the work W while being held by the holding head 34, for example, and individually discharge the treatment liquid downward. The holding head 34 may be configured to be movable in a direction along the surface Wa of the work W by a driving unit (not shown). Although the number of the plurality of nozzles 32 is not limited, the case where the processing liquid supply unit 30 has 12 nozzles 32 (hereinafter, referred to as “nozzles 32A to 32L”) will be described below as an example.

The processing liquid is supplied from the supply unit 36 to each of the nozzles 32A to 32L. Different types of treatment liquids may be supplied to the nozzles 32A to 32L from the supply unit 36. As an example, different types of resists are supplied to the nozzles 32A to 32J from the supply unit 36, and different types of thinner are supplied to the

nozzles

32K and 32L from the supply unit 36, respectively.

As shown in FIG. 4, the supply unit 36 includes a plurality of supply pipes 42A to 42L and a plurality of supply sources 44A to 44L. The supply pipe 42A forms a flow path between the supply source 44A, which is a liquid source of the processing liquid supplied to the nozzle 32A (discharged from the nozzle 32A), and the nozzle 32A. The supply source 44A includes, for example, a bottle in which the treatment liquid is stored and a pump for pumping the treatment liquid from the bottle toward the nozzle 32A. Similar to the supply pipes 42A, the supply pipes 42B to 42L also form flow paths between the supply sources 44B to 44L, which are the liquid sources of the treatment liquid, and the nozzles 32B to 32L, respectively.

The supply unit 36 further includes a plurality of on-off valves V provided in each of the plurality of supply pipes 42A to 42L. The on-off valve V switches to the open state or the closed state based on the operation instruction of the control device 18. By switching the open / closed state of the plurality of open / close valves V, the flow paths of the supply pipes 42A to 42L are opened and closed respectively. For example, when the on-off valve V is opened, the processing liquid flows into the flow paths of the supply pipes 42A to 42L, and the processing liquid is discharged from the nozzles 32A to 32L to the surface Wa of the work W.

(Foreign matter detection unit)
The coating / developing device 2 further includes a foreign matter detecting unit 50 (foreign matter detecting device) configured to detect foreign matter (particles) contained in the processing liquid supplied to the work W. The foreign matter detection unit 50 is configured to detect foreign matter in the processing liquid flowing through the flow paths of the plurality of supply pipes 42A to 42L, for example. The foreign matter detection unit 50 may be arranged in the vicinity of the liquid treatment unit U1 or may be arranged in the housing of the liquid treatment unit U1. Some elements of the foreign matter detection unit 50 may be provided between the on-off valve V on the flow path of the supply pipes 42A to 42L and the nozzles 32A to 32L. Hereinafter, an example of the foreign matter detection unit 50 will be described with reference to FIGS. 5 to 10.

The foreign matter detection unit 50 forms a flow path (hereinafter, referred to as “treatment liquid flow path”) through which the treatment liquid flowing through the supply pipes 42A to 42L is circulated. The foreign matter detection unit 50 detects foreign matter in the processing liquid flowing through the treatment liquid flow path by receiving the light generated by irradiating the treatment liquid flow path with irradiation light (for example, laser light). As shown in FIG. 5, the foreign matter detection unit 50 includes, for example, a housing 52 and a detection unit 53. The housing 52 includes an upper wall 54a, a bottom wall 54b, and side walls 56a to 56d (see also FIG. 7). As an example, the upper wall 54a and the bottom wall 54b are arranged horizontally (along the XY plane), respectively. Further, the

side walls

56a and 56b are arranged vertically (along the YY plane) along the Y-axis direction, and face each other in the X-axis direction (first direction). Further, the

side walls

56c and 56d are arranged vertically (along the XX plane) along the X-axis direction and face each other in the Y-axis direction (second direction). The housing 52 accommodates the detection unit 53. The detection unit 53 includes a flow path forming unit 60 and a measuring unit 70.

The flow path forming unit 60 forms a plurality of processing liquid flow paths provided on the flow paths of the supply pipes 42A to 42L, respectively. Each of the plurality of treatment liquid flow paths formed by the flow path forming unit 60 is used for detecting foreign matter contained in the treatment liquid flowing through the treatment liquid flow path. The flow path forming portion 60 has, for example, a plurality of processing liquid flow path forming portions 62A to 62L as shown in FIG. The plurality of processing liquid flow path forming portions 62A to 62L are configured in the same manner as each other. Hereinafter, the details of the treatment liquid flow path forming portion will be described by taking the treatment liquid flow path forming portion 62A as an example.

As shown in FIG. 5, the treatment liquid flow path forming unit 62A forms the treatment liquid flow path 64 on the flow path of the supply pipe 42A connecting the supply source 44A and the nozzle 32A (see also FIG. 4). The upstream and downstream ends of the treatment liquid flow path 64 are connected to the supply pipe 42A. As a result, the treatment liquid pumped from the supply source 44A is a part of the flow path of the supply pipe 42A, the treatment liquid flow path 64 of the treatment liquid flow path forming portion 62A, and the remaining part of the flow path of the supply pipe 42A. Is discharged from the nozzle 32A to the surface Wa of the work W in this order.

The treatment liquid flow path forming unit 62A includes, for example, a block body 66 in which the treatment liquid flow path 64 is formed. The block body 66 is made of a material capable of transmitting laser light used for detecting foreign matter. Examples of the material constituting the block body 66 include quartz and sapphire. The block body 66 may be formed in a rectangular parallelepiped shape, or one surface of the block body 66 may face the side wall 56a. As an example, the inflow port 64a and the outflow port 64b of the treatment liquid flow path 64 are formed on the surface of the block body 66 facing the side wall 56a. The inflow port 64a may be located below the outflow port 64b.

The treatment liquid flow path 64 includes, for example, a first flow path 68a, a second flow path 68b, and a third flow path 68c. The first flow path 68a is formed so as to extend horizontally (along the X-axis direction in the figure) along the bottom wall 54b. One end of the first flow path 68a near the side wall 56a constitutes an inflow port 64a, and the other end of the first flow path 68a near the side wall 56b is connected to the second flow path 68b. The second flow path 68b is formed so as to extend along the side wall 56a (along the Z-axis direction) in the vertical direction. One end of the second flow path 68b near the bottom wall 54b is connected to the first flow path 68a, and the other end of the second flow path 68b near the upper wall 54a is connected to the third flow path 68c. The third flow path 68c is formed so as to extend horizontally (along the X-axis direction) along the bottom wall 54b. One end of the third flow path 68c near the side wall 56b is connected to the second flow path 68b, and the other end of the third flow path 68c near the side wall 56a constitutes an outlet 64b.

A supply pipe (hereinafter referred to as "upstream supply pipe 46") on the upstream side of the treatment liquid flow path forming portion 62A of the supply pipe 42A is connected to the inflow port 64a. A supply pipe (hereinafter, referred to as “downstream side supply pipe 48”) on the downstream side of the treatment liquid flow path forming portion 62A of the supply pipe 42A is connected to the outflow port 64b. The upstream side supply pipe 46 and the downstream side supply pipe 48 penetrate the side wall 56a on which the block main body 66 faces. With the above configuration, the processing liquid sent out from the supply source 44A passes through the upstream side supply pipe 46, the first flow path 68a, the second flow path 68b, the third flow path 68c, and the downstream side supply pipe 48 in this order. It is supplied to the work W from the nozzle 32A.

As described above, the treatment liquid flow path forming portions 62A to 62L shown in FIG. 6 are configured in the same manner as each other. Therefore, the treatment liquid flow path forming portions 62B to 62L each include a block main body 66 in which the treatment liquid flow path 64 is formed, similarly to the treatment liquid flow path forming portion 62A. Each of the treatment liquid flow paths 64 of the treatment liquid flow path forming portions 62B to 62L includes a first flow path 68a, a second flow path 68b, and a third flow path 68c. The upstream supply pipes 46 of the supply pipes 42B to 42L are connected to the inflow ports 64a (first flow paths 68a) of the treatment liquid flow path forming portions 62B to 62L, respectively. The downstream supply pipes 48 of the supply pipes 42B to 42L are connected to the outlets 64b (third flow paths 68c) of the treatment liquid flow path forming portions 62B to 62L, respectively.

The treatment liquid flow path forming portions 62A to 62L are arranged side by side (along the Y-axis direction) along the direction from the side wall 56d to the side wall 56c in a state where each of the treatment liquid flow path forming portions 62A to 62L faces the side wall 56a. The treatment liquid flow path forming portions 62A to 62L may be arranged in this order with a distance from each other. The height positions (positions in the Z-axis direction) of the first flow paths 68a of the treatment liquid flow path forming portions 62A to 62L may be substantially coincident with each other. The distances (positions in the X-axis direction) of the second flow paths 68b of the treatment liquid flow path forming portions 62A to 62L from the side wall 56a may be substantially the same as each other. The height positions (distance from the bottom wall 54b) of the third flow path 68c of the treatment liquid flow path forming portions 62A to 62L may be substantially the same as each other.

Returning to FIG. 5, the measuring unit 70 is configured to receive the emitted light emitted from the processing liquid flow path 64 by irradiating the processing liquid flow path 64 with the irradiation light from the light source 72. The measuring unit 70 includes, for example, a light source 72, an irradiation unit 74, a light receiving unit 76, a holding unit 78, and a driving unit 80. The light source 72 generates laser light as irradiation light for detecting foreign matter in the processing liquid. The light source 72 emits, for example, a laser beam having a wavelength of about 400 nm to 600 nm and an output of about 600 mW to 1000 mW. The light source 72 is provided on the bottom wall 54b, for example, as shown in FIG. 7, and is arranged below the treatment liquid flow path forming portions 62A to 62L. As an example, the light source 72 emits a laser beam in a direction (Y-axis negative direction) from the side wall 56d toward the side wall 56c. The light source 72 is arranged at a position different from that of the processing liquid flow path forming portion 62A in the Y-axis direction. The light source 72 is arranged apart from the processing liquid flow path forming portion 62A in the Y-axis direction. In the Y-axis direction, for example, the light source 72 and the treatment liquid flow path forming portions 62A to 62L are arranged so as to be arranged in this order.

The irradiation unit 74 is configured to irradiate the irradiation light from the light source 72 toward the treatment liquid flow path 64 of the treatment liquid flow path forming units 62A to 62L, respectively. The irradiation unit 74 is configured to individually irradiate the irradiation light toward the treatment liquid flow path 64 of the treatment liquid flow path forming units 62A to 62L, for example. The irradiation unit 74 may be arranged below the treatment liquid flow path 64. The irradiation unit 74 has, for example, an optical member 82 configured to irradiate the irradiation light toward the processing liquid flow path 64 by changing the direction of the irradiation light from the light source 72.

The optical member 82 includes, for example, a reflection member 82a and a condenser lens 82b. The reflective surface of the reflective member 82a faces the light source 72 in the Y-axis direction. The reflecting surface of the reflecting member 82a reflects the irradiation light emitted substantially horizontally from the light source 72 upward. The condensing lens 82b is arranged above the reflecting member 82a, and condenses the irradiation light reflected by the reflecting member 82a at a measurement position set in the processing liquid flow path 64. The condenser lens 82b is configured so that, for example, the irradiation light is applied to the measurement position set in the first flow path 68a of the treatment liquid flow path 64.

The holding portion 78 movably holds the optical member 82. The holding portion 78 has, for example, a guide rail 88 and a slide base 84. The guide rail 88 is provided on the bottom wall 54b and is formed so as to extend in the direction from the side wall 56c toward the side wall 56d (along the Y-axis direction). For example, as shown in FIG. 7, the guide rail 88 may extend along the Y-axis direction from at least the treatment liquid flow path forming portion 62A to the treatment liquid flow path forming portion 62L. The guide rail 88 movably supports the slide base 84.

The slide base 84 is arranged below the processing liquid flow path forming portions 62A to 62L and supports the optical member 82 (reflection member 82a). As shown in FIG. 5, the slide base 84 may be formed so as to extend along a direction (for example, the X-axis direction) intersecting the guide rail 88. For example, in the slide table 84, one end near the side wall 56a is located below the treatment liquid flow path forming portion 62A, and the other end near the side wall 56b is the treatment liquid flow path forming portion 62A. It is located closer to the side wall 56b than the position of. As an example, the optical member 82 is arranged at one end of the slide base 84 near the side wall 56a.

The drive unit 80 moves the slide base 84 along the guide rail 88 by a power source such as an electric motor. As the slide base 84 moves along the guide rail 88, the irradiation unit 74 (optical member 82) moves along the Y-axis direction.

The light receiving unit 76 is configured to receive the emitted light emitted from the processing liquid flow path 64 of the processing liquid flow path forming units 62A to 62L by irradiating the irradiation light from the irradiation unit 74. The light receiving unit 76 is configured to individually receive, for example, the light emitted from the processing liquid flow path 64 of the processing liquid flow path forming units 62A to 62L. The light receiving portion 76 may be arranged so as to sandwich the treatment liquid flow path forming portions 62A to 62L between the light receiving portion 76 and the side wall 56a.

The light receiving unit 76 includes, for example, an optical member 92 and a light receiving element 94. The processing liquid flow path forming portion 62A, the optical member 92, and the light receiving element 94 are arranged in this order in the direction from the side wall 56a to the side wall 56b (X-axis direction). The height positions of the optical member 92 and the light receiving element 94 substantially coincide with the height positions of the first flow path 68a of the processing liquid flow path 64, for example.

The optical member 92 includes, for example, a condensing lens that collects light emitted from the processing liquid flow path 64 (hereinafter, referred to as “emitted light”) toward the light receiving element 94. A wavelength filter that allows only light having a specific wavelength to pass through may be provided inside the optical member 92. The light receiving element 94 receives the emitted light collected by the optical member 92 and generates an electric signal corresponding to the received light (detection light). The light receiving element 94 includes, for example, a photodiode that performs photoelectric conversion.

The optical member 92 and the light receiving element 94 are attached to a support member 86 extending along the vertical direction. The support member 86 is connected to the slide base 84. For example, the lower end of the support member 86 is connected to the end portion of the slide base 84 opposite to the end portion where the optical member 82 is provided. As the slide base 84 is moved by the drive unit 80, the optical member 92 and the light receiving element 94 move along the Y-axis direction.

With the above configuration, the drive unit 80 moves the irradiation unit 74 and the light receiving unit 76 together along the Y-axis direction by moving the slide base 84. The drive unit 80 has, for example, a position where the irradiation unit 74 and the light receiving unit 76 face each other with the processing liquid flow path forming unit 62A, and a position where the irradiation unit 74 and the light receiving unit 76 face each other with the processing liquid flow path forming unit 62L. The irradiation unit 74 and the light receiving unit 76 are moved between the irradiation units 74. Hereinafter, the position where the irradiation unit 74 and the light receiving unit 76 face each other of the processing liquid flow path forming portion is referred to as a position corresponding to the processing liquid flow path forming portion.

As an example, in a state where the irradiation light from the light source 72 to the optical member 82 continues, the optical member is placed below any one of the processing liquid flow paths 64 of the processing liquid flow path forming portions 62A to 62L by the driving unit 80. As the 82 moves, the treatment liquid flow path 64 is irradiated with irradiation light from the irradiation unit 74. At this time, the light receiving element 94 receives the light emitted from the processing liquid flow path 64.

As described above, the irradiation unit 74 is arranged below the measurement position set in the processing liquid flow path 64, and the light receiving unit 76 is arranged on the side of the measurement position. Therefore, when the light receiving unit 76 irradiates any one of the treatment liquid flow paths 64 with the irradiation light, the light receiving unit 76 scatters the emission light (scattering) generated by scattering the irradiation light at the measurement position in the treatment liquid flow path 64. Light) is partly received. When the irradiation light is irradiated into the treatment liquid flow path 64 through which the treatment liquid flows, scattered light is generated. When no foreign matter is contained in the treatment liquid, most of the irradiation light passes through the treatment liquid flow path 64. On the other hand, when the processing liquid contains foreign matter, the degree of scattering of the irradiation light in the treatment liquid flow path 64 becomes large, and the light received by the light receiving unit 76 is higher than that in the case where the treatment liquid does not contain foreign matter. The intensity of (a part of the scattered light toward the light receiving unit 76) is increased. When the treatment liquid is a resist, the treatment liquid usually contains a base resin (base polymer) as a main component. Since the irradiation light can be scattered by this base polymer as well, the light receiving unit 76 can receive light having a certain amplitude even if the processing liquid does not contain foreign matter.

The foreign matter detection unit 50 may further include a control unit 100. The control unit 100 controls each element (detection unit 53) of the foreign matter detection unit 50. The control unit 100 is arranged inside the housing 52, for example. As an example, the control unit 100 controls each element of the foreign matter detection unit 50 based on an operation instruction from the control device 18. The control unit 100 has at least the signal intensity of the emitted light emitted from the processing liquid flow path 64 when the treatment liquid flow path 64 through which the treatment liquid supplied to the work W flows is irradiated with the irradiation light from the light source 72. Based on the above, it is determined whether or not the processing liquid contains foreign matter, and based on the signal intensity of the emitted light, the intensity information indicating the intensity of the background light contained in the emitted light is acquired. It is configured to do.

As shown in FIG. 8, the control unit 100 has, as a functional configuration (hereinafter, referred to as “functional module”), for example, a signal acquisition unit 102, a foreign matter determination unit 104, a processing information acquisition unit 106, and the like. It has a drive control unit 108, a strength information acquisition unit 122, a reference information holding unit 112, a condition monitoring unit 124, and an output unit 116. The processing executed by the signal acquisition unit 102, the foreign matter determination unit 104, the processing information acquisition unit 106, the drive control unit 108, the strength information acquisition unit 122, the reference information holding unit 112, the condition monitoring unit 124, and the output unit 116 is the control unit. Corresponds to the process executed by 100.

The signal acquisition unit 102 acquires an electric signal corresponding to the intensity of the emitted light from the light receiving unit 76. The signal acquisition unit 102 corresponds to, for example, the intensity of the emitted light emitted from the processing liquid flow path 64 (first flow path 68a) through which the processing liquid to be monitored flows among the processing liquid flow path forming units 62A to 62L. The electric signal is acquired from the light receiving element 94. The signal acquisition unit 102 acquires, for example, an electric signal having an amplitude corresponding to the intensity of the emitted light. The signal acquisition unit 102 may acquire the electric signal at a predetermined sampling cycle.

The foreign matter determination unit 104 detects the presence or absence of foreign matter in the processing liquid based on the intensity such as the amplitude of the electric signal according to the emitted light (hereinafter, referred to as “signal intensity”). FIG. 9 shows a graph showing an example of the time change of the signal strength obtained from the signal acquisition unit 102. As described above, since the degree of scattering of the irradiation light in the treatment liquid flow path 64 (inside the treatment liquid) changes depending on the presence or absence of foreign matter, the magnitude of the signal intensity also changes depending on the presence or absence of foreign matter. As shown in FIG. 9, the electric signal corresponding to the emitted light includes the signal Ib corresponding to the background light in the state where the foreign matter is not contained and the scattered light from the foreign matter in the state where the foreign matter is contained. Corresponding signal Is (more specifically, signal Is corresponding to the background light and the scattered light scattered by the foreign matter) may be included. The signal Ib corresponding to the background light may include a component corresponding to the scattered light from a substance (for example, the above-mentioned base polymer or the like) usually contained in the treatment liquid and a component corresponding to the disturbance.

For example, as shown in FIG. 9, the foreign matter determination unit 104 determines that the treatment liquid contains a foreign matter when the signal strength is larger than a predetermined threshold value Th. The foreign matter determination unit 104 determines that the processing liquid does not contain foreign matter when the signal strength is equal to or less than a predetermined threshold value Th. The threshold value Th is a value set in advance in consideration of the intensity of the scattered light when the irradiation light is scattered by the foreign matter in the treatment liquid. The foreign matter determination unit 104 may determine the presence or absence of foreign matter in the processing liquid at each sampling cycle in which the signal acquisition unit 102 acquires the signal strength.

The processing information acquisition unit 106 acquires information on the processing executed by the liquid processing unit U1 (hereinafter, referred to as “processing information”) from the control device 18. The processing information includes, for example, information indicating a nozzle (processing liquid to be detected for foreign matter) to be discharged in the liquid processing unit U1 and information indicating a supply start timing and supply time of the processing liquid. The processing information acquisition unit 106 may acquire processing information from the control device 18 before the start of supply of the processing liquid for each processing using one processing liquid.

The drive control unit 108 moves the irradiation unit 74 and the light receiving unit 76 by moving the slide base 84 by the drive unit 80 between the processing liquid flow path forming unit 62A and the processing liquid flow path forming unit 62L. The drive control unit 108 is driven to, for example, a position corresponding to the processing liquid flow path 64 through which the processing liquid passes among the processing liquid flow path forming units 62A to 62L according to the processing liquid to be detected indicated by the processing information. The irradiation unit 74 and the light receiving unit 76 are moved by the unit 80. The drive control unit 108 may move the irradiation unit 74 and the light receiving unit 76 to a position corresponding to the processing liquid flow path 64 by the drive unit 80 before the supply of the processing liquid to be detected is started. ..

The intensity information acquisition unit 122 acquires information indicating the intensity of the background light included in the emitted light (hereinafter, referred to as “intensity information”) based on the signal intensity. The intensity information acquisition unit 122 may acquire the time average of the signal intensity included in the predetermined period as intensity information based on the signal intensity acquired by the signal acquisition unit 102 in the predetermined sampling cycle. The intensity information acquisition unit 122 may calculate, for example, the time average of the acquired values of the signal strength included in the predetermined period when the predetermined period has passed. The intensity information acquisition unit 122 may calculate the average value of the acquired values of the signal strength included in the predetermined period as a time average, and may calculate the integrated value obtained by integrating the time change of the signal intensity included in the predetermined period. It may be calculated as a time average.

Note that the intensity information acquisition unit 122 may acquire a signal intensity value (instantaneous value) for each sampling cycle as intensity information instead of the time average. The intensity information acquisition unit 122 may acquire the maximum value, the median value, the minimum value, or the most frequent value of the signal intensities obtained in a predetermined period as intensity information. The intensity information acquisition unit 122 may acquire the signal intensity (baseline value) according to the scattered light derived from a substance (for example, the above-mentioned base polymer or the like) normally contained in the treatment liquid as intensity information. The intensity information acquisition unit 122 may acquire the magnitude of a specific frequency component in the frequency distribution obtained by frequency analysis of the signal intensity obtained in a predetermined period as intensity information. The predetermined period may be predetermined by, for example, a worker.

The reference information holding unit 112 holds reference information for confirming the state of the discharged processing liquid or the state of the foreign matter detection unit 50 (detection unit 53). The reference information holding unit 112 may hold (store), for example, the intensity of the background light (hereinafter, referred to as “reference intensity”) acquired in the normal state of the treatment liquid and the detection unit 53. For example, the reference strength may be preset in the reference information holding unit 112 by the worker, or the treatment liquid and the detection unit 53 may be subjected to a process of acquiring strength information in a normal state.

The condition monitoring unit 124 monitors (determines) whether or not at least one of the treatment liquid and the detection unit 53 is normal by comparing the intensity information acquired by the intensity information acquisition unit 122 with the reference intensity. May be good. If the state of the treatment liquid and the detection unit 53 is constant, it is considered that the intensity of the background light falls within a certain range. However, for example, the intensity of the background light also differs depending on the type of the treatment liquid for which the foreign matter is detected. Further, the intensity of the background light also differs depending on the mixing of another solution with the treatment liquid to be detected for foreign matter or the deterioration of the treatment liquid. Therefore, the condition monitoring unit 124 may monitor whether or not the type of the treatment liquid is appropriate based on the strength information, and the treatment liquid is not deteriorated or another solution is mixed in the treatment liquid. You may monitor if it is not.

If the state of the optical system included in the detection unit 53 is constant, it is considered that the intensity of the background light falls within a certain range. However, for example, the intensity of the background light also changes due to a change (deterioration) of the optical system of the detection unit 53 with time. As an example of deterioration of the optical system, deterioration of the lens performance due to a decrease in the output of the laser light from the light source 72, cloudiness / dirt of the condenser lens, deterioration of the antireflection film, etc., and an optical axis of the optical system due to an external impact or thermal expansion. Misalignment (alignment misalignment) can be mentioned. The condition monitoring unit 124 may monitor the condition of the optical system of the detection unit 53 based on the intensity information.

For example, the condition monitoring unit 124 may determine that the condition of the treatment liquid and the detection unit 53 is normal when the intensity indicated by the intensity information is included in the range obtained by adding a tolerance to the reference intensity. Frequently, when it is out of the range, it may be determined that at least one of the treatment liquid and the detection unit 53 is not in a normal state. The condition monitoring unit 124 may, for example, perform the above comparison and determination every predetermined period for calculating the time average, or may perform the above comparison and determination for each supply of one treatment liquid. ..

The output unit 116 outputs the determination result and the monitoring result to the outside of the foreign matter detection unit 50, respectively. The output unit 116 may output the determination result of foreign matter detection and the monitoring result of at least one of the treatment liquid and the detection unit 53 to the control device 18, respectively, and output to a display or the like that notifies the operator of the result. You may. For example, when the foreign matter determination unit 104 determines that the foreign matter is contained, the output unit 116 outputs an alarm signal indicating that the processing liquid to be monitored contains the foreign matter. Alternatively, when it is determined that at least one of the states of the processing liquid and the detection unit 53 is not normal, the output unit 116 outputs an alarm signal indicating that the state is not normal.

The control unit 100 is composed of one or a plurality of control computers. For example, the control unit 100 has a circuit 200 shown in FIG. The circuit 200 includes one or more processors 202, a memory 204, a storage 206, an input / output port 208, and a timer 212. The storage 206 has a computer-readable storage medium, such as a hard disk. The storage medium stores a program for causing the control unit 100 to execute the foreign matter detection 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 204 temporarily stores the program loaded from the storage medium of the storage 206 and the calculation result by the processor 202.

The processor 202 configures each functional module by executing the above program in cooperation with the memory 204. The input / output port 208 inputs / outputs an electric signal to / from the control device 18, the light receiving unit 76, the drive unit 80, and the like in accordance with a command from the processor 202. The timer 212 measures the elapsed time, for example, by counting a reference pulse having a fixed cycle. The hardware configuration of the control unit 100 is not necessarily limited to the one in which each functional module is configured by a program. For example, each functional module of the control unit 100 may be configured by a dedicated logic circuit or an ASIC (Application Specific Integrated Circuit) in which the logic circuit is integrated.

[Foreign matter detection method]
Subsequently, with reference to FIG. 11, a foreign matter detection method (foreign matter detection procedure) by the foreign matter detection unit 50 will be described. FIG. 11 is a flowchart showing an example of a foreign matter detecting method executed in the substrate processing including the supply of the processing liquid once.

While the irradiation of the irradiation light from the light source 72 is continued, for example, when the processing information acquisition unit 106 acquires the processing information from the control device 18, the control unit 100 executes step S01. In step S01, for example, the drive control unit 108 moves the slide base 84 by the drive unit 80 to a position corresponding to the processing liquid flow path 64 through which the processing liquid to be detected as a foreign matter indicated by the processing information flows, so that the irradiation unit 74 And the light receiving unit 76 are moved. As a result, the processing liquid flow path 64 through which the treatment liquid to be detected as a foreign substance flows is irradiated with irradiation light from the irradiation unit 74, and the light emitted from the treatment liquid flow path 64 is received by the light receiving unit 76. The supply of the processing liquid indicated by the processing information to the work W may be started before the execution of step S01 or at substantially the same timing as step S01.

Next, the control unit 100 executes steps S02 and S03. In step S02, for example, the signal acquisition unit 102 acquires the signal intensity according to the detection light received by the light receiving unit 76. In step S03, for example, the foreign matter determination unit 104 determines whether or not the signal strength obtained in step S02 is greater than the threshold value Th. If it is determined in step S03 that the signal strength is greater than the threshold Th (step S03: YES), the control unit 100 executes step S04. In step S04, for example, the output unit 116 outputs an alarm signal indicating that the processing liquid to be detected for foreign matter contains foreign matter. On the other hand, if it is determined in step S03 that the signal strength is equal to or less than the threshold value Th (step S03: NO), the control unit 100 does not execute step S04.

Next, the control unit 100 executes step S05. In step S05, for example, the control unit 100 determines whether or not the supply of the processing liquid to be monitored has been completed. The control unit 100 may determine whether or not the supply of the processing liquid has been completed by measuring the elapsed time from the supply start timing included in the processing information. If it is determined in step S05 that the supply of the processing liquid to be monitored has not been completed (step S05: NO), the control unit 100 repeats the processes of steps S02 and S03. As a result, during the supply period of the processing liquid, monitoring of whether or not foreign matter is contained in the processing liquid is continued, and the signal acquisition unit 102 acquires the signal intensity according to the detected light in a predetermined sampling cycle. do.

If it is determined in step S05 that the supply of the processing liquid to be monitored has been completed (step S05: YES), the control unit 100 executes step S06. In step S06, the intensity information acquisition unit 122 acquires intensity information indicating the intensity of the background light included in the light emitted from the processing liquid flow path 64 based on the signal intensity. For example, the intensity information acquisition unit 122 acquires intensity information based on the signal intensity (time change of signal intensity) obtained in the supply period in which step S02 is repeatedly executed. As an example, the intensity information acquisition unit 122 calculates the average value or the integrated value of the signal intensities obtained during the supply period as the intensity information.

Next, the control unit 100 executes step S07. In step S07, for example, the condition monitoring unit 124 compares the intensity information acquired by the intensity information acquisition unit 122 with the reference intensity to determine whether or not at least one of the states of the treatment liquid and the detection unit 53 is normal. You may judge. For example, the condition monitoring unit 124 determines that at least one of the treatment liquid and the detection unit 53 is normal when the intensity indicated by the intensity information is included in the range obtained by adding a tolerance to the reference intensity. Alternatively, if it is out of the range, it may be determined that at least one of the treatment liquid and the detection unit 53 is not in a normal state.

If it is determined in step S07 that at least one of the states of the treatment liquid and the detection unit 53 is not normal (step S07: YES), the control unit 100 executes step S08. In step S08, for example, the output unit 116 outputs an alarm signal indicating that the state of at least one of the processing liquid and the detection unit 53 is not normal. On the other hand, if it is determined in step S08 that the states of the treatment liquid and the detection unit 53 are normal (step S07: NO), the control unit 100 does not execute step S08. This completes a series of foreign matter detection procedures. The control unit 100 may execute the processes of steps S01 to S08 for each substrate process by supplying the process liquid.

The above-mentioned foreign matter detection procedure is an example, and the step order, execution timing, execution content, etc. can be changed as appropriate. For example, in step S06, the intensity information acquisition unit 122 calculates the average value or the integrated value of the signal strength obtained in the divided period as the intensity information for each divided period obtained by dividing the supply period in chronological order. May be good. Alternatively, the intensity information acquisition unit 122 calculates the average value of the signal intensities obtained in the predetermined period before the period for each one cycle or two or more cycles of the sampling cycle, thereby increasing the intensity of the moving average of the signal intensities. It may be calculated as information.

The strength information acquisition unit 122 may repeat the calculation of the strength information at the timing when the step S02 is repeatedly executed instead of the step S06. That is, the intensity information acquisition unit 122 may calculate the intensity information for each sampling cycle. In this case, the condition monitoring unit 124 may determine the state of at least one of the processing liquid and the detection unit 53 for each calculation of the intensity information (for each sampling cycle) instead of step S07. As an example, the intensity information acquisition unit 122 may calculate the moving average of the signal intensity as intensity information by calculating the average value of the signal intensities obtained in the predetermined period before the period for each sampling cycle. .. Alternatively, the intensity information acquisition unit 122 may calculate the average value or the integrated value of the signal intensities obtained from the start of supply of the processing liquid to the period as intensity information for each sampling cycle.

[Effect of Embodiment]
In the foreign matter detecting unit 50 or the foreign matter detecting method in the foreign matter detecting unit 50 exemplified above, in addition to detecting the foreign matter based on the emitted light emitted from the processing liquid flow path 64 by the irradiation of the irradiation light, the background included in the emitted light is included. Light intensity information is acquired. Since the strength information changes based on the state of the detection unit 53 or the treatment liquid, the foreign matter detection unit 50 can confirm whether or not the state of the device or the treatment liquid is normal.

When detecting foreign matter in the treatment liquid based on the light obtained by irradiating the flow path through which the treatment liquid flows with irradiation light, the treatment liquid is detected by detecting whether or not the intensity of the received detection light changes. The presence or absence of foreign matter inside is determined. However, even if the hardware such as the optical system included in the foreign matter detection device is not operating normally or the state of the treatment liquid is different from the normal state, the intensity of the detected light does not change and the inside of the treatment liquid does not change. Can be determined to be free of foreign matter. In the above-mentioned foreign matter detection unit 50, the state of the processing liquid and the state of the detection unit 53 including the optical system can be confirmed by acquiring the intensity information of the background light, so that the foreign matter detection result is made more reliable. be able to. In addition, the signal related to the emitted light emitted from the processing liquid flow path acquired for detecting foreign matter also includes information on the background light. Therefore, the foreign matter detection unit 50 according to the above embodiment can easily check the state of the treatment liquid or the device without providing a configuration for checking the state.

The light emitted from the treatment liquid flow path 64 is the light obtained by the irradiation light scattered in the treatment liquid flow path 64. In this case, the transmitted light itself transmitted through the processing liquid flow path 64 is not obtained by the detector (light receiving unit 76), and the intensity of the background light is also, for example, when the transmitted light is received (when the detection is performed by forward scattering). Therefore, the change in the intensity of the detected light due to the presence or absence of foreign matter in the treatment liquid can be detected with high accuracy. Therefore, according to the above configuration, it is possible to more reliably detect foreign matter. Further, since the transmitted light itself transmitted through the processing liquid flow path 64 is not obtained, it is easy to detect a minute change in the intensity of the background light.

The intensity information acquisition unit 122 acquires the time average of the signal intensity obtained in a predetermined period as intensity information. The intensity of the background light can vary depending on the time of day obtained. Therefore, in this configuration, it is possible to more reliably confirm the state of the apparatus or the treatment liquid based on the time average.

The foreign matter determination unit 104 determines whether or not the treatment liquid contains foreign matter during the supply period from the start of supply of the treatment liquid to the work W to the end of supply. The strength information acquisition unit 122 acquires strength information based on the signal strength obtained during the supply period. In this case, the state of the processing liquid or the detection unit 53 can be efficiently confirmed by using the information obtained during the supply period. That is, it is possible to check the state of the treatment liquid or the apparatus without passing the treatment liquid through the treatment liquid for checking the state other than the supply period.

The foreign matter detection unit 50 further includes a state monitoring unit 124 that monitors the state of at least one of the processing liquid and the detection unit 53 based on the strength information. In this case, foreign matter can be detected after confirming the state of the detection unit 53 or the treatment liquid. Therefore, the detection result of the foreign matter can be made more reliable.

In the coating / developing device 2 provided with the foreign matter detecting unit 50, it is possible to confirm the state of the foreign matter detecting unit 50 and whether or not the processing liquid is normal, and the supply unit 36 detects the foreign matter in the processing liquid. Therefore, it is possible to detect a defect of the work W due to a foreign substance at an early stage.

[Modification example]
The light receiving unit 76 may include a plurality of light receiving elements 94 arranged side by side in the direction (horizontal direction) in which the processing liquid flow path forming units 62A to 62L are arranged or in the vertical direction. Alternatively, the light receiving unit 76 may include a plurality of light receiving elements 94 two-dimensionally arranged in the horizontal direction and the vertical direction. For example, the light receiving unit 76 may include a photodiode array in which photodiodes are arranged one-dimensionally or two-dimensionally. The light receiving unit 76 may output a plurality of electric signals obtained from each of the plurality of light receiving elements 94 to the control unit 100. The signal acquisition unit 102 may acquire the signal strength for each electric signal from each light receiving element 94.

In this case, the reference information holding unit 112 may acquire intensity information indicating the intensity of the background light for each of the signal intensities obtained from the plurality of light receiving elements 94. That is, the reference information holding unit 112 may acquire intensity information for each light receiving position where the light receiving element 94 is provided. When the optical system included in the detection unit 53 is displaced in the optical axis, it is conceivable that the distribution of the light received by the light receiving unit 76 is different (for example, the distribution of the light is biased). Therefore, the condition monitoring unit 124 may monitor the deviation of the optical axis of the optical system included in the detection unit 53 based on the intensity information for each light receiving position. For example, the condition monitoring unit 124 determines whether or not the difference in intensity indicated by the intensity information is larger than a predetermined value at a plurality of light receiving positions arranged in one direction, thereby shifting the optical axis of the optical system (for example, collecting). The deviation of the focal position of the optical lens) may be monitored.

Immediately after the start of discharge of the treatment liquid and just before the end of discharge, the flow rate (flow velocity) of the treatment liquid changes. As the flow rate changes, the intensity of the background light contained in the emitted light also changes. Therefore, in the supply period from the start of supply of the treatment liquid to the stop of supply, the time change of the intensity of the background light changes according to the time change of the flow rate (flow velocity) in the supply period. The condition monitoring unit 124 monitors whether or not the treatment liquid is normally discharged (whether the flow rate of the treatment liquid is within the set range) according to the time change of the background light intensity during the supply period. May be good.

The intensity information acquisition unit 122 may perform a correction process for removing the influence of the signal Is based on the scattered light from the foreign matter. For example, the intensity information acquisition unit 122 may exclude the signal intensity as an abnormal value when the signal intensity is larger than the same value or a different value (another threshold value) from the threshold value Th. Alternatively, the intensity information acquisition unit 122 may exclude the signal intensity as an abnormal value when the difference between the signal intensity and the calculated moving average is larger than a predetermined value.

In the above example, the state of the processing liquid and the detection unit 53 is monitored by the control unit 100, but the state may be monitored by an operator instead of the control unit 100. In this case, the control unit 100 may output the acquired (calculated) background light intensity information to the outside, and the worker monitors the state by comparing the output intensity information with the reference information. May be good.

At least a part of the processing liquid flow path 64 flowing through the block body 66 may be formed so as to extend in a direction other than the horizontal direction and the vertical direction. The inflow port 64a and the outflow port 64b of the treatment liquid flow path 64 may be formed on different surfaces of the block body. The treatment liquid flow paths 64 of the treatment liquid flow path forming portions 62A to 62L may be configured to be different from each other.

The treatment liquid flow path forming portions 62A to 62L may include a liquid passage pipe for supply through which the treatment liquid flows, instead of the block main body 66. The treatment liquid flow path 64 may be a flow path in the liquid passage pipe for supply. The liquid passage tube may be made of a material capable of transmitting irradiation light (for example, quartz or sapphire). The foreign matter detection unit 50 may have one treatment liquid flow path forming portion instead of the treatment liquid flow path forming portions 62A to 62L.

The foreign matter detection unit 50 may include a drive unit for irradiation that moves the irradiation unit 74 along the Y-axis direction and a drive unit for light reception that moves the light-receiving unit 76 along the Y-axis direction. These two drive units may be configured to move the irradiation unit 74 and the light receiving unit 76 along the Y-axis direction. The irradiation unit 74 includes the light source 72, and the irradiation light may be applied to the treatment liquid flow paths 64 of the treatment liquid flow path forming units 62A to 62L, respectively, without passing through the optical member 82.

The light receiving unit 76 may receive a part of the transmitted light obtained by transmitting the irradiation light from the irradiation unit 74 through the processing liquid flow path 64. In this case, the irradiation unit 74 and the light receiving unit 76 may be arranged so as to sandwich the processing liquid flow path forming units 62A to 62L in the vertical direction (Z-axis direction).

In the above example, the intensity information acquisition unit 122 acquires the intensity information of the background light based on the signal intensity of the scattered light obtained during the supply period of the processing liquid, but is obtained in a state where the processing liquid is not supplied. The strength information may be acquired based on the signal strength. Specifically, in the strength information acquisition unit 122, the treatment liquid flow path 64 is filled with the treatment liquid (the treatment liquid exists in the treatment liquid flow path 64), and the work W is processed. Intensity information may be acquired based on the signal intensity obtained in the state where the liquid is not supplied. For example, after the on-off valve V shown in FIG. 4 is closed and the supply of the processing liquid to the work W is stopped, the nozzle is formed in the flow path (treatment liquid flow path 64) between the on-off valve V and the nozzle. It is filled with the treatment liquid that was not discharged from. In this state, the signal acquisition unit 102 may acquire the signal intensity according to the scattered light from the processing liquid flow path 64 in which the flow of the processing liquid is stopped inside, and the intensity is based on the signal intensity. The information acquisition unit 122 may acquire strength information.

The intensity information acquisition unit 122 (control unit 100) acquires the intensity information based on the signal intensity in the above-mentioned supply period and the intensity information based on the signal intensity in the non-supply period when the processing liquid is not supplied. Either one of the above may be performed, or both may be performed. When acquiring the intensity information in both the supply period and the non-supply period, the control unit 100 determines that the length between one supply period and the next supply period (the length of the non-supply period) is longer than the predetermined time. In this case, the strength information based on the signal strength in the non-supply period may be acquired. When the strength information is acquired only during the supply period, the period during which the treatment liquid or the device is not confirmed based on the strength information (unconfirmed time) depends on the length of the non-supply period determined by the treatment schedule. On the other hand, when the intensity information is acquired in both periods, the length of the unconfirmed time can be adjusted without depending on the length determined by the processing schedule.

In this modification, the strength information acquisition unit 122 is based on the signal strength obtained in a state where the treatment liquid flow path 64 is filled with the treatment liquid and the treatment liquid is not supplied to the work W. Get strength information. In this case, since the component of the disturbance that can be contained in the background light can be reduced due to the treatment liquid flowing in the treatment liquid flow path 64, the state of the apparatus or the treatment liquid can be confirmed more accurately.

The specific configuration of the substrate processing apparatus is not limited to the configuration of the coating / developing apparatus 2 illustrated above. The substrate processing apparatus may be any as long as it includes a foreign matter detecting unit 50 that detects foreign matter in the processing liquid supplied to the substrate. The treatment liquid to be monitored by the foreign matter detection unit 50 may be a solution for forming a film other than the resist film (for example, the above-mentioned lower layer film or upper layer film), or a solution for substrate treatment other than film formation. May be good. All or part of the functional modules included in the control unit 100 of the foreign matter detection unit 50 may be executed by the control device 18. In this case, the foreign matter detection device may be configured by the foreign matter detection unit 50 and the control device 18.

1 ... Substrate processing system, 2 ... Coating / developing device, 30 ... Processing liquid supply unit, 32A to 32L ... Nozzle, 36 ... Supply unit, 50 ... Foreign matter detection unit, 53 ... Detection unit, 60 ... Flow path forming unit, 62A -62L ... Processing liquid flow path forming unit, 64 ... Processing liquid flow path, 72 ... Light source, 74 ... Irradiating unit, 76 ... Light receiving unit, 100 ... Control unit, 122 ... Intensity information acquisition unit, 124 ... Condition monitoring unit, U1 ... Liquid processing unit, W ... Work.

Claims

The flow path forming portion that forms the treatment liquid flow path through which the treatment liquid supplied to the substrate flows, and the emission light emitted from the treatment liquid flow path when the treatment liquid flow path is irradiated with the irradiation light from the light source. A detector having a measuring unit configured to receive light,
A foreign matter determination unit that determines whether or not a foreign matter is contained in the processing liquid based on the signal intensity of the emitted light, and a foreign matter determination unit.
An intensity information acquisition unit that acquires intensity information indicating the intensity of the background light included in the emitted light based on the signal intensity, and an intensity information acquisition unit.
A foreign matter detection device.
The foreign matter detection device according to claim 1, wherein the emitted light is light in which the irradiation light is scattered in the processing liquid flow path.
The foreign matter detection device according to claim 1 or 2, wherein the intensity information acquisition unit acquires the time average of the signal intensity obtained in a predetermined period as the intensity information.
The foreign matter determination unit determines whether or not the treatment liquid contains foreign matter during the supply period from the start of supply of the treatment liquid to the end of supply to the substrate.
The foreign matter detection device according to any one of claims 1 to 3, wherein the intensity information acquisition unit acquires the intensity information based on the signal intensity obtained during the supply period.
The strength information acquisition unit is based on the signal strength obtained in a state where the treatment liquid is filled in the treatment liquid flow path and the treatment liquid is not supplied to the substrate. The foreign matter detection device according to any one of claims 1 to 3, which acquires strength information.
The foreign matter detection device according to any one of claims 1 to 5, further comprising a condition monitoring unit that monitors the state of at least one of the processing liquid and the detection unit based on the strength information.
A treatment liquid supply unit having a nozzle for discharging the treatment liquid toward the substrate and a supply unit for supplying the treatment liquid to the nozzle.
The flow path forming portion forming the treatment liquid flow path through which the treatment liquid flows and the treatment liquid flow path are irradiated with the irradiation light from the light source so as to receive the emission light emitted from the treatment liquid flow path. A detection unit having a measurement unit configured in
A foreign matter determination unit that determines whether or not a foreign matter is contained in the processing liquid based on the signal intensity of the emitted light, and a foreign matter determination unit.
An intensity information acquisition unit that acquires intensity information indicating the intensity of the background light included in the emitted light based on the signal intensity, and an intensity information acquisition unit.
A board processing device.
When the treatment liquid flow path through which the treatment liquid supplied to the substrate flows is irradiated with the irradiation light from the light source, foreign matter is generated in the treatment liquid based on the signal intensity of the emitted light emitted from the treatment liquid flow path. Determining if it is included and
A method for detecting a foreign substance, which comprises acquiring intensity information indicating the intensity of background light included in the emitted light based on the signal intensity.
A computer-readable storage medium that stores a program for causing the device to execute the foreign matter detection method according to claim 8.