Substrate processing apparatus and substrate processing method

Abstract

To make countermeasures for preventing a processing liquid from being applied to a substrate by a slit nozzle with foreign objects adhering to a nozzle guard in a substrate processing device in which the nozzle guard is disposed forward of the slit nozzle which is moved relative to the substrate.SOLUTION: The invention relates to a substrate processing device and a substrate processing method which move a slit nozzle and a plate-like nozzle guard relative to a substrate with a processing liquid discharged from a discharge port of the slit nozzle in a state where the discharge port is placed close to a surface of the substrate to apply the processing liquid to the surface of the substrate while preventing foreign objects from adhering to the slit nozzle with the nozzle guard provided forward of the slit nozzle in a relative movement direction in which the slit nozzle is relatively moved. Before application of the processing liquid is performed in this way, foreign objects adhering to the nozzle guard are detected.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a substrate processing technique for applying a processing liquid from a slit nozzle to a substrate such as a glass substrate for FPDs such as liquid crystal display devices and organic EL display devices, semiconductor wafers, glass substrates for photomasks, substrates for color filters, substrates for recording disks, substrates for solar cells, substrates for electronic papers, and substrates for semiconductor packages (hereinafter simply referred to as "substrates").

Background Art

[0002] There is known a substrate processing apparatus that applies a processing liquid to a substrate by discharging the processing liquid from a slit nozzle while relatively moving the slit nozzle having a slit-shaped discharge port with respect to the substrate. For example, in the apparatus described in Patent Document 1, the processing liquid is applied by moving the slit nozzle above the stage surface while holding the substrate on the stage surface of the stage. On the other hand, in the apparatus described in Patent Document 2, the substrate is moved in a so-called floating method while positioning the slit nozzle at a predetermined coating position above the stage surface of the stage. More specifically, the substrate is moved so as to pass through a coating region sandwiched between the slit nozzle and the stage surface while being floated by a pressure gas layer formed on the stage surface by a gas flow passing through gas holes provided in the stage surface, and the processing liquid is applied. Although the substrate conveyance methods are different in this way, nozzle guards are provided in any of the apparatuses. This is in consideration of the fact that foreign matters and protrusions (hereinafter referred to as "foreign matters") may protrude upward on the surface side of the substrate. That is, if the application of the processing liquid is performed with these foreign matters present, the slit nozzle collides with the foreign matters, thereby inhibiting the application of the processing liquid. That is, the above collision may have an adverse effect on the applied processing liquid and the slit nozzle. Therefore, in the above conventional apparatus, the nozzle guard is disposed on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate.

Prior Art Documents

Patent Documents

[0003] [Patent Document 1] Japanese Patent Publication No. 2006-102609 [Patent Document 2] Japanese Patent Publication No. 2011-212544 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] Incidentally, when removing foreign matter using a nozzle guard, the foreign matter may adhere to the nozzle guard. Depending on the size of the foreign matter, when coating is performed using a slit nozzle equipped with such a nozzle guard, the foreign matter may come into contact with the substrate, causing defects. Furthermore, if coating is repeated using the slit nozzle with foreign matter still attached, defects will occur in the same location on multiple sheets in a row.

[0005] This invention has been made in view of the above problems, and aims to provide a substrate processing technology that can take measures to prevent foreign matter from adhering to the nozzle guard and then being applied to the substrate by the slit nozzle, in a substrate processing apparatus in which a nozzle guard is arranged on the front side of a slit nozzle that moves relative to the substrate. [Means for solving the problem]

[0006] This invention First The embodiment is a substrate processing apparatus for applying a processing liquid to the surface of a substrate, comprising: a slit nozzle having a slit-shaped discharge port for discharging the processing liquid; a nozzle moving unit above the substrate, which moves the slit nozzle, with its discharge port facing downward, relative to the substrate in a direction along the surface of the substrate; a plate-shaped nozzle guard provided on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate by the nozzle moving unit when applying the processing liquid, and which moves integrally with the slit nozzle; and a foreign matter detection unit for detecting foreign matter adhering to the nozzle guard. When a foreign object is detected by the foreign object detection unit, the control unit restricts the application of the processing liquid to the substrate, the foreign object removal unit removes the foreign object from the nozzle guard, and the nozzle cleaning unit cleans the slit nozzle. Equipped with The control unit controls the foreign matter removal unit so that foreign matter is removed from the nozzle guard while the coating operation is restricted. The foreign matter removal unit is located in front of the nozzle cleaning unit in the relative direction of movement, and at a distance from the nozzle cleaning unit equal to the distance from the slit nozzle to the nozzle guard. The control unit controls the nozzle cleaning unit and the foreign matter removal unit so that the cleaning of the slit nozzle by the nozzle cleaning unit and the removal of foreign matter by the foreign matter removal unit are performed at least partially in parallel. It is characterized by the following. Furthermore, a second aspect of the present invention is a substrate processing apparatus for applying a processing liquid to the surface of a substrate, comprising: a slit nozzle having a slit-shaped discharge port for discharging the processing liquid; a nozzle moving unit above the substrate, which moves the slit nozzle, with its discharge port facing downward, relative to the substrate in a direction along the surface of the substrate; a plate-shaped nozzle guard provided on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate by the nozzle moving unit when applying the processing liquid, and which moves integrally with the slit nozzle; a foreign matter detection unit for detecting foreign matter adhering to the nozzle guard; and a nozzle moving toward the surface of the substrate. The device includes a pre-discharge unit that, before discharging the processing liquid from the discharge port of the slit nozzle, waits at a pre-discharge position away from the substrate by discharging a preset amount of processing liquid from the discharge port of the slit nozzle, and a control unit that controls the pre-discharge unit and a foreign object detection unit. The foreign object detection unit is located in front of the pre-discharge unit in the relative direction of movement, and at a distance from the pre-discharge unit equal to the distance from the slit nozzle to the nozzle guard. The control unit controls the pre-discharge unit and the foreign object detection unit so that the discharging or waiting of processing liquid at the pre-discharge unit and the detection of foreign objects at the foreign object detection unit are performed at least partially in parallel. Furthermore, a third aspect of the present invention is a substrate processing apparatus for applying a processing liquid to the surface of a substrate, comprising: a slit nozzle having a slit-shaped discharge port for discharging the processing liquid; a nozzle moving unit that moves the slit nozzle, with its discharge port facing downward, relative to the substrate in a direction along the surface of the substrate, above the substrate; a plate-shaped nozzle guard provided on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate by the nozzle moving unit when applying the processing liquid, and which moves integrally with the slit nozzle; and a foreign matter detection unit for detecting foreign matter adhering to the nozzle guard, wherein the foreign matter detection unit is characterized by detecting foreign matter based on the amount of light received by the light receiver while integrally moving along the tip of the nozzle guard a light emitter that emits a parallel light beam parallel to the relative movement direction toward the tip of the nozzle guard and a light receiver that receives and receives the parallel light beam that has come forward without being blocked by the nozzle guard. Furthermore, a fourth aspect of the present invention is a substrate processing apparatus for applying a processing liquid to the surface of a substrate, comprising: a slit nozzle having a slit-shaped discharge port for discharging the processing liquid; a nozzle moving unit that moves the slit nozzle, with its discharge port facing downward, relative to the substrate in a direction along the surface of the substrate, above the substrate; a plate-shaped nozzle guard provided on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate by the nozzle moving unit when applying the processing liquid, and which moves integrally with the slit nozzle; and a foreign matter detection unit for detecting foreign matter adhering to the nozzle guard, wherein the foreign matter detection unit detects foreign matter based on a projection image of the nozzle guard taken along the tip of the nozzle guard while emitting light from a direction parallel to the relative movement direction. Furthermore, a fifth aspect of the present invention is a substrate processing apparatus for applying a processing liquid to the surface of a substrate, comprising: a slit nozzle having a slit-shaped discharge port for discharging the processing liquid; a nozzle moving unit that moves the slit nozzle, with its discharge port facing downward, relative to the substrate in a direction along the surface of the substrate, above the substrate; a plate-shaped nozzle guard provided on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate by the nozzle moving unit when applying the processing liquid, and which moves integrally with the slit nozzle; and a foreign matter detection unit for detecting foreign matter adhering to the nozzle guard, wherein the foreign matter detection unit detects foreign matter based on an image of the nozzle guard taken from below along the tip of the nozzle guard.

[0007] Furthermore, this invention The sixth The embodiment is a substrate processing method, comprising: a coating step in which a processing liquid is applied to the surface of a substrate while a slit nozzle and a plate-shaped nozzle guard are moved relative to the substrate while the discharge port of the slit nozzle is brought close to the surface of the substrate and a processing liquid is discharged from the discharge port, thereby preventing foreign matter from adhering to the slit nozzle by the nozzle guard which is provided on the front side of the slit nozzle in the relative direction of movement of the slit nozzle; and a detection step in which foreign matter is detected to adhere to the nozzle guard before the coating step. The system includes the steps of: restricting the application of processing liquid to the substrate when a foreign object is detected by a foreign object detection unit; removing the foreign object from the nozzle guard by a foreign object removal unit while the application operation is restricted; and cleaning the slit nozzle by a nozzle cleaning unit, wherein the foreign object removal unit is located in front of the nozzle cleaning unit in the relative direction of movement, and at a distance from the nozzle cleaning unit equal to the distance from the slit nozzle to the nozzle guard, and the cleaning of the slit nozzle by the nozzle cleaning unit and the removal of foreign objects by the foreign object removal unit are performed at least partially in parallel. It is characterized by the following. Furthermore, a seventh aspect of the present invention is a substrate processing method comprising: a coating step of applying a processing liquid to the surface of a substrate by discharging a processing liquid from the discharge port of a slit nozzle while keeping the discharge port of the slit nozzle close to the surface of the substrate, thereby preventing foreign matter from adhering to the slit nozzle with a nozzle guard provided on the front side of the slit nozzle in the relative movement direction of the slit nozzle; a detection step of detecting the adhesion of foreign matter to the nozzle guard by a foreign matter detection unit before the coating step; and a step of discharging a preset amount of processing liquid from the discharge port of the slit nozzle at a preliminary discharge position away from the substrate by a preliminary discharge unit and waiting before discharging the processing liquid from the discharge port of the slit nozzle toward the surface of the substrate, wherein the foreign matter detection unit is provided on the front side of the preliminary discharge unit in the relative movement direction and at a distance from the preliminary discharge unit equal to the distance from the slit nozzle to the nozzle guard, and the discharging or waiting of processing liquid by the preliminary discharge unit and the detection of foreign matter by the foreign matter detection unit are performed at least partially in parallel. Furthermore, an eighth aspect of the present invention is a substrate processing method comprising: a coating step in which a processing liquid is applied to the surface of a substrate while a slit nozzle and a plate-shaped nozzle guard are moved relative to the substrate while the discharge port of the slit nozzle is brought close to the surface of the substrate and a processing liquid is discharged from the discharge port, thereby preventing foreign matter from adhering to the slit nozzle by the nozzle guard which is provided on the front side of the slit nozzle in the relative movement direction of the slit nozzle; and a detection step in which a foreign matter detection unit detects the adhesion of foreign matter to the nozzle guard before the coating step. The foreign object detection unit comprises a light emitter that projects a parallel light beam parallel to the relative direction of movement toward the tip of the nozzle guard, and a light receiver that receives the parallel light beam that has come forward without being blocked by the nozzle guard. These two components are moved integrally along the tip of the nozzle guard, and the foreign object is detected based on the amount of light received by the light receiver. It is characterized by the following. Furthermore, a ninth aspect of the present invention is a substrate processing method comprising: a coating step in which a processing liquid is applied to the surface of a substrate while a slit nozzle and a plate-shaped nozzle guard are moved relative to the substrate while the discharge port of the slit nozzle is brought close to the surface of the substrate and a processing liquid is discharged from the discharge port, thereby preventing foreign matter from adhering to the slit nozzle by the nozzle guard which is provided on the front side of the slit nozzle in the relative movement direction of the slit nozzle; and a detection step in which foreign matter is detected by a foreign matter detection unit before the coating step. The foreign object detection unit is characterized by detecting foreign objects based on a projection image of the slit nozzle, which is captured along the tip of the slit nozzle while emitting light from a direction parallel to the relative movement direction. Furthermore, a tenth aspect of the present invention is a substrate processing method comprising: a coating step in which a processing liquid is applied to the surface of a substrate while a slit nozzle and a plate-shaped nozzle guard are moved relative to the substrate while the discharge port of the slit nozzle is brought close to the surface of the substrate and a processing liquid is discharged from the discharge port, thereby preventing foreign matter from adhering to the slit nozzle by the nozzle guard which is provided on the front side of the slit nozzle in the relative movement direction of the slit nozzle; and a detection step in which foreign matter is detected by a foreign matter detection unit before the coating step, The foreign object detection unit is characterized by detecting foreign objects based on an image of the slit nozzle taken from below along the tip of the slit nozzle.

[0008] In this configuration, the coating process is performed while removing foreign matter using a nozzle guard positioned in front of the slit nozzle that moves in the relative direction. As a result, foreign matter may adhere to the nozzle guard. Therefore, in this invention, a foreign matter detection unit is provided to detect the adhesion of foreign matter to the nozzle guard. [Effects of the Invention]

[0009] As described above, according to the present invention, it is possible to detect the adhesion of foreign matter to the nozzle guard positioned in front of the slit nozzle that moves relative to the substrate, and various measures can be taken to prevent the coating process from being carried out with foreign matter still attached to the nozzle guard before the coating process. [Brief explanation of the drawing]

[0010] [Figure 1] This is a diagram schematically showing the overall configuration of a coating apparatus which is a first embodiment of a substrate processing apparatus according to the present invention. [Figure 2] This is a side view schematically showing the coating apparatus shown in FIG. 1. [Figure 3] This is a perspective view showing the overall configuration and operation of a foreign matter detection unit. [Figure 4] This is a diagram schematically showing the operation of a foreign matter detection unit. [Figure 5] This is a flowchart showing the coating operation executed by the coating apparatus shown in FIG. 1. [Figure 6] This is a diagram schematically showing the foreign matter detection operation in a coating apparatus which is a second embodiment of a substrate processing apparatus according to the present invention. [Figure 7] This is a diagram schematically showing the foreign matter detection operation in a coating apparatus which is a third embodiment of a substrate processing apparatus according to the present invention. [Figure 8] This is a side view schematically showing a coating apparatus which is a fourth embodiment of a substrate processing apparatus according to the present invention. [Figure 9] This is a diagram schematically showing the operation of a dry guard cleaner which is an example of a foreign matter removal unit provided in a coating apparatus which is a fifth embodiment of a substrate processing apparatus according to the present invention. [Figure 10] This is a diagram schematically showing the operation of the dry guard cleaner shown in FIG. 9. [Figure 11] This is a diagram schematically showing the operation of a dry guard cleaner which is an example of a foreign matter removal unit provided in a coating apparatus which is a sixth embodiment of a substrate processing apparatus according to the present invention. [Figure 12] This is a diagram schematically showing the operation of the dry guard cleaner shown in FIG. 11. [Figure 13] This is a perspective view schematically showing the configuration and operation of a dry guard cleaner which is an example of a foreign matter removal unit provided in a coating apparatus which is a seventh embodiment of a substrate processing apparatus according to the present invention. [Figure 14] This is a diagram schematically showing the operation of the dry guard cleaner shown in FIG. 13. [Figure 15] This is a schematic perspective view showing the configuration and operation of a dry guard cleaner, which is an example of a foreign matter removal unit equipped in a coating apparatus, which is the eighth embodiment of the substrate processing apparatus according to the present invention. [Figure 16] Figure 15 is a schematic diagram illustrating the operation of the dry guard cleaner. [Figure 17] This is a perspective view showing the overall configuration and operation of a dry guard cleaner, which is an example of a foreign matter removal unit equipped in a coating apparatus, which is the ninth embodiment of the substrate processing apparatus according to the present invention. [Figure 18] Figure 17 is a schematic diagram illustrating the operation of the dry guard cleaner. [Figure 19] This figure schematically shows the configuration and operation of a foreign matter removal unit equipped in a coating apparatus, which is the tenth embodiment of the substrate processing apparatus according to the present invention. [Figure 20A] This figure schematically shows the configuration and operation of a foreign matter removal unit equipped in a coating apparatus, which is the 11th embodiment of the substrate processing apparatus according to the present invention. [Figure 20B] This figure schematically shows the configuration and operation of a foreign matter removal unit equipped in a coating apparatus, which is the 11th embodiment of the substrate processing apparatus according to the present invention. [Figure 21] This figure schematically shows the overall configuration of a coating apparatus, which is the tenth embodiment of the substrate processing apparatus according to the present invention. [Modes for carrying out the invention]

[0011] Figure 1 is a schematic diagram showing the overall configuration of a coating apparatus, which is a first embodiment of the substrate processing apparatus according to the present invention. Figure 2 is a schematic side view showing the coating apparatus shown in Figure 1. In order to clarify the directional relationships between Figures 1, 2, and subsequent figures, an XYZ Cartesian coordinate system is appropriately attached, in which the Z direction is the vertical direction and the XY plane is the horizontal plane, and the dimensions and number of parts are exaggerated or simplified as necessary. Also, in Figure 2, some components such as the nozzle support are omitted.

[0012] The coating apparatus 1A is a coating apparatus called a slit coater that applies a processing solution to the surface 31 of a substrate 3, which is an example of an object to be coated, using a slit nozzle 2. The processing solution is, for example, a photoresist solution. Alternatively, the processing solution may be various paste-like or slurry-like solutions containing, for example, a pigment for a color filter, a polyimide precursor, a silicon agent, a nanometal ink, or a conductive material. The substrate 3 is a glass substrate having a rectangular shape in plan view. Furthermore, the substrate 3 to be coated can be various substrates such as rectangular glass substrates, semiconductor substrates, flexible substrates for film liquid crystals, substrates for photomasks, substrates for color filters, substrates for solar cells, substrates for organic EL (ElectroLuminescence), and substrates for semiconductor packages. In this specification, "surface 31 of the substrate 3" means the main surface of the substrate 3 on which the processing solution is applied.

[0013] The coating apparatus 1A includes a stage 4 capable of holding a substrate 3 in a horizontal position by suction, a coating processing unit 5 that applies a coating process to the substrate 3 held on the stage 4 using a slit nozzle 2, a nozzle maintenance unit 6 that performs maintenance on the slit nozzle 2 and nozzle guard NG, and a control unit 10 that controls each of these parts.

[0014] Stage 4 is made of a stone material such as granite, which has a roughly rectangular parallelepiped shape. On its upper surface (+Z side), on the (-Y) side, there is a holding surface 41 which is processed into a roughly horizontal flat surface to hold the substrate 3. Numerous vacuum suction ports (not shown) are dispersed on the holding surface 41. The substrate 3 is held horizontally in a predetermined position by being adsorbed by these vacuum suction ports during the coating process. Note that the method of holding the substrate 3 is not limited to this, and for example, the substrate 3 may be held mechanically. Furthermore, a nozzle adjustment area RA is provided on the (+Y) side of the area occupied by the holding surface 41 in Stage 4, and a nozzle maintenance unit 6 is located in this nozzle adjustment area RA.

[0015] As shown in Figures 1 and 2, the slit nozzle 2 has a shape that tapers downwards at its lower end 2a (nozzle lip). A slit-shaped discharge port 21 extends in the X direction from the lower surface of the lower end 2a, and the processing liquid, which is pumped from a processing liquid supply unit (not shown), is discharged from the discharge port 21 onto the surface 31 of the substrate 3. In this way, the processing liquid is applied to the surface 31 of the substrate 3.

[0016] The coating processing unit 5 has a nozzle support 51 that supports the slit nozzle 2. This nozzle support 51 has a support member 51a that extends parallel to the X direction above the stage 4, and two lifting mechanisms 51b that support the support member 51a from both sides in the X direction and raise and lower the support member 51a. The support member 51a is a rod member made of carbon fiber reinforced resin or the like and has a rectangular cross-section. The lower surface of this support member 51a is the mounting location 510 for the slit nozzle 2, and the support member 51a detachably supports the slit nozzle 2 at the mounting location 510. Various fastening mechanisms such as latches or screws can be used as appropriate for attaching and detaching the slit nozzle 2 to and from the mounting location 510 of the support member 51a.

[0017] The two lifting mechanisms 51b are connected to both longitudinal ends of the support member 51a and each has an AC servo motor and a ball screw, respectively. These lifting mechanisms 51b raise and lower the support member 51a and the slit nozzle 2 fixed thereto in the vertical direction (Z direction), adjusting the distance between the discharge port 21 that opens at the lower end of the slit nozzle 2 and the substrate 3, that is, the relative height of the discharge port 21 with respect to the substrate 3. The vertical position of the support member 51a can be detected by a linear encoder, which consists of a scale provided on the side of the lifting mechanism 51b and a detection sensor provided on the side of the slit nozzle 2 opposite the scale, although this is not shown in the figure.

[0018] As shown in Figure 1, the nozzle support 51 configured in this way has a cross-linking structure that spans the holding surface 41, which is stretched across both the left and right ends of the stage 4 along the X direction. The coating processing unit 5 has a nozzle moving unit 53 that moves the nozzle support 51 in the Y direction. The nozzle moving unit 53 functions as a relative moving means that moves the nozzle support 51 as a cross-linking structure and the slit nozzle 2 supported thereon relative to the substrate 3 held on the stage 4 along the Y direction. Specifically, the nozzle moving unit 53 has, on each of the ±X sides, a guide rail 52 that guides the movement of the slit nozzle 2 in the Y direction, a linear motor 54 which is a drive source, and a linear encoder 55 for detecting the position of the discharge port 21 of the slit nozzle 2.

[0019] The two guide rails 52 are each provided at both ends of the stage 4 in the X direction and extend in the Y direction to include the section where the nozzle adjustment area RA and the holding surface 41 are provided. The two guide rails 52 each guide the movement of the two lifting mechanisms 51b in the Y direction. The two linear motors 54 are each provided on both sides of the stage 4 and are AC coreless linear motors having a stator 54a and a mover 54b. The stator 54a is provided on the X-side of the stage 4 along the Y direction. The mover 54b, on the other hand, is fixed to the outside of the lifting mechanism 51b. The two linear motors 54 each drive the two lifting mechanisms 51b in the Y direction by the magnetic force generated between the stator 54a and the mover 54b.

[0020] Each linear encoder 55 also has a scale section 55a and a detection section 55b. The scale section 55a is provided along the Y direction at the lower part of the stator 54a of the linear motor 54 fixed to the stage 4. On the other hand, the detection section 55b is fixed further outside the movable element 54b of the linear motor 54 fixed to the lifting mechanism 51b, and is positioned opposite the scale section 55a. The linear encoder 55 detects the position of the discharge port 21 of the slit nozzle 2 in the Y direction based on the relative positional relationship between the scale section 55a and the detection section 55b.

[0021] The nozzle moving unit 53 configured in this way can move the slit nozzle 2 between the area above the nozzle adjustment region RA and the area above the substrate 3 held on the stage 4 by driving the nozzle support 51 in the Y direction. The coating apparatus 1A then moves the slit nozzle 2 in the (+Y) direction from the coating start position Pst to the coating end position Pen while discharging the processing liquid from the discharge port 21 of the slit nozzle 2, thereby forming a processing liquid layer on the surface 31 of the substrate 3. Thus, in this embodiment, the (+Y) direction corresponds to an example of the "relative movement direction" of the present invention.

[0022] While the slit nozzle 2 is moved relative to the substrate 3 in the (+Y) direction, the processing liquid is applied. However, if foreign matter is present on the surface 31 of the substrate 3, the discharge port 21 of the slit nozzle 2 may come into contact with the foreign matter and be damaged. Therefore, as shown in Figures 1 and 2, a plate-shaped nozzle guard NG is positioned on the front side of the slit nozzle 2 in the relative movement direction (+Y) (the diagonally lower right side in Figure 1 and the right side in Figure 2). This nozzle guard NG has a width in the X direction that is approximately the same as that of the slit nozzle 2. As shown in Figure 2, the nozzle guard NG is attached to the side of the slit nozzle 2 on the (+Y) side, at a distance D1 in the (+Y) direction from the discharge port 21 of the slit nozzle 2, with its lower end protruding below the discharge port 21 of the slit nozzle 2. Therefore, during the processing liquid application process, the lower end of the nozzle guard NG approaches the surface 31 of the substrate 3 from above, protecting the discharge port 21 of the slit nozzle 2 from foreign matter on the surface 31 of the substrate 3.

[0023] After the application of the processing liquid is complete, the slit nozzle 2 moves further in the (+Y) direction and waits in the nozzle adjustment area RA. This nozzle adjustment area RA is located away from the holding surface 41 of the substrate 3 in the (+Y) direction. The nozzle adjustment area RA functions as a waiting area for the slit nozzle 2 during periods when no coating process is performed on the stage 4, such as during the transfer period of the substrate 3 between the coating device 1A and the external transport mechanism (the loading and unloading period of the substrate 3). In addition, the nozzle maintenance unit 6 performs various maintenance on the slit nozzle 2 located in the nozzle adjustment area RA.

[0024] The nozzle maintenance unit 6 includes a nozzle cleaning standby unit 7 for performing so-called predipence processing, a foreign matter detection unit 8 for detecting foreign matter adhering to the nozzle guard NG, and a nozzle cleaning unit 9 for cleaning the slit nozzle 2. These are arranged in the (+Y) direction. For the purpose of explaining their positional relationship later, the positions of the nozzle cleaning standby unit 7, foreign matter detection unit 8, and nozzle cleaning unit 9 in the Y direction are defined as positions Ppd, Pdt, and Pnc, respectively.

[0025] Of these, the nozzle cleaning unit 9 corresponds to an example of the "nozzle cleaning unit" of the present invention, and for example, one described in Japanese Patent Application Publication No. 2018-149468 can be used. The nozzle cleaning unit 9 is equipped with a scraper (contact member) 91. The scraper 91 contacts the outer surface of the lower end of the slit nozzle 2 (specifically the inclined surface of the lip portion) and moves along the outer surface in the X direction by a drive mechanism (not shown) (scraping operation). As a result, the scraper 91 scrapes off and removes any deposits adhering to the lower end 2a of the slit nozzle 2.

[0026] The nozzle cleaning standby unit 7 is located on the (-Y) side of the nozzle cleaning unit 9, flanking the foreign matter detection unit 8. The nozzle cleaning standby unit 7 has a pre-dispense roller 72 that is partially immersed in the cleaning liquid stored in the storage tank 71. This pre-dispense roller 72 has a length equal to or greater than that of the slit nozzle 2 in the X direction. This pre-dispense roller 72 is rotated by the drive of a motor (not shown). In this embodiment, before performing the coating process, a small amount of resist liquid (processing liquid) is discharged from the slit nozzle 2, which has moved above the pre-dispense roller 72, thereby removing the resist liquid containing the cleaning liquid used in the nozzle cleaning unit 9 from inside the slit nozzle 2 (pre-discharge process). This pre-discharge process makes it possible to discharge a resist liquid suitable for coating that does not contain impurities. The slit nozzle 2 then waits in the nozzle cleaning standby unit 7 in preparation for the next coating process.

[0027] Figure 3 is a perspective view showing the overall configuration and operation of the foreign object detection unit. As shown in Figure 2, the foreign object detection unit 8 is located between the nozzle cleaning standby unit 7 and the nozzle cleaning unit 9. More specifically, the foreign object detection unit 8 is located at a foreign object detection position Pdt, which is a distance D2 (+Y) away from the pre-dispense roller 72. In this embodiment, this distance D2 coincides with the distance D1 from the discharge port 21 of the slit nozzle 2 to the nozzle guard NG in the Y direction, as shown in Figure 2. Therefore, when the slit nozzle 2 is positioned at the pre-dispense position Ppd corresponding to the pre-dispense roller 72 in order to perform preliminary discharge processing, the tip of the nozzle guard NG is positioned at the foreign object detection unit 8 configured as follows, and the foreign object detection processing can be performed in parallel with the preliminary discharge processing.

[0028] The foreign object detection unit 8 comprises a light emitter 81, a light receiver 82, and an amplifier unit 83. The amplifier unit 83 incorporates a light-emitting unit and a light intensity detection unit. The light emitter 81 and the light receiver 82 each have a light-emitting window and a light-receiving window of the same shape. The light emitter 81 and the light receiver 82 are erected above the amplifier unit 83 with their light-emitting and light-receiving windows facing each other and separated by a predetermined distance in the Y direction. Here, the predetermined distance is set to be slightly wider than the thickness of the tip of the nozzle guard NG, and as shown in Figure 3, the tip of the nozzle guard NG can be sandwiched between the light emitter 81 and the light receiver 82. The light emitter 81 converts the light emitted from the light-emitting unit into a parallel light beam using an internal lens, and then reflects it in the (+Y) direction with an internal mirror, thereby projecting the parallel light beam towards the light receiver 82. Meanwhile, the light receiver 82 receives the parallel light beam from the light emitter 81, reflects the direction of the light with its built-in mirror, and then guides the light to the light intensity detection unit via its built-in lens. The light intensity detection unit then outputs a value proportional to the amount of light received (hereinafter referred to as "received light amount information") to the control unit 10. In this embodiment, a foreign object detection unit 8 is used which integrates the light emitter 81, the light receiver 82, and the amplifier unit 83. However, the amplifier unit 83 may be spaced apart from the light emitter 81 and the light receiver 82, with the light emitter and the light emitter 81 connected by a first optical fiber and the light receiver 82 and the light intensity detection unit connected by a second optical fiber.

[0029] As shown in Figure 3, the foreign object detection unit 8 is provided to be able to move back and forth in the X direction. The foreign object detection unit 8 is also connected to a movement mechanism 84. Therefore, when the movement mechanism 84 is activated in response to a movement command from the control unit 10, the foreign object detection unit 8 moves between the front position P(X1) and the back position P(Xmax) while gripping the tip of the nozzle guard NG. While moving in this manner, the light-emitting unit continues to emit light continuously or at regular intervals in response to a lighting command from the control unit 10. Meanwhile, the light intensity detection unit outputs light intensity information.

[0030] Figure 4 schematically shows the operation of the foreign object detection unit. In the figure, "sensor position" indicates the position of the foreign object detection unit 8 in the X direction, "light shielding status" indicates the situation in which the parallel light beam traveling from the light emitter 81 to the light receiver 82 is shielded by the tip of the nozzle guard NG, and "amount of light received" indicates the amount of light received by the light intensity detection unit. Here, the amount of light received when the nozzle guard NG is not present between the light emitter 81 and the light receiver 82 is set to 100. When the foreign object detection unit 8 moves to a position on the tip of the nozzle guard NG where no foreign object is attached (a position other than position P(Xn) in the figure), the amount of light received decreases to 60. However, when the foreign object detection unit 8 moves to a position where foreign object F is attached (position P(Xn) in the figure), the amount of light received decreases further by an amount corresponding to the amount of foreign object F, becoming 50. Therefore, the control unit 10 can identify the presence or absence of foreign object F and the location where foreign object F is attached based on the change in the amount of light received.

[0031] To control each part of the coating apparatus 1A configured as described above, a control unit 10 is provided as described above. This control unit 10 has the configuration of a general computer system in which an arithmetic unit (e.g., CPU) that performs various calculations, and a storage unit (e.g., ROM or RAM) that stores basic programs and various information are connected to a bus line. The bus line is further connected to a fixed disk (e.g., hard disk drive) that stores coating programs and the like, a display unit (e.g., a display) that shows various information, and an input unit (e.g., a keyboard and mouse) that accepts input from the operator. For example, a touch panel display that integrates the functions of the display unit and the input unit may be used. Furthermore, the control unit 10 receives signals sent from sensors and the like provided in each part of the apparatus via an interface (not shown in the figure), and controls each part of the apparatus according to the basic program to execute the coating process described below.

[0032] Figure 5 is a flowchart showing the coating operation performed by the coating apparatus shown in Figure 1. In this coating apparatus 1A, after the slit nozzle 2 used for the coating process moves to the pre-dispense position Ppd, a preliminary discharge process is performed (step S11). In parallel with the preliminary discharge process, a foreign object detection process is performed. That is, the tip of the nozzle guard NG enters between the light emitter 81 and the light receiver 82, blocking a portion of the parallel light beam traveling from the light emitter 81 to the light receiver 82. Light reception amount information corresponding to the light blocking situation at this time is provided to the control unit 10. This operation is performed in accordance with the movement of the foreign object detection unit 8 in the X direction, and as shown in Figure 4, light reception amount information at sensor positions P(X1), ..., P(Xn), ..., P(Xmax) is sequentially acquired and temporarily stored in the memory unit of the control unit 10.

[0033] Based on the light intensity information obtained in this way, the calculation unit of the control unit 10 determines whether or not foreign matter F (Figure 4) is attached to the nozzle guard NG (step S12). If foreign matter is detected to be attached to the nozzle guard NG (NO in step S12), the foreign matter removal operation (steps S13 to S15) is executed. That is, the coating process is interrupted in step S13. Following this restriction of the coating operation, the calculation unit of the control unit 10 displays a message on the display unit requesting the user to clean the nozzle guard NG while the coating operation remains restricted, prompting the user to clean the nozzle guard NG (step S14). When the user cleans the nozzle guard NG and operates a button or icon corresponding to the completion of cleaning (YES in step S15), the foreign matter removal operation is terminated, and the control unit 10 returns to step S11, and the preliminary dispensing operation and foreign matter detection operation are repeated. In this embodiment, the display unit is used to notify the user of the temporary restriction of the coating operation and the request to clean the nozzle guard NG, but other notification means, such as lamps or sounds, may also be used.

[0034] On the other hand, when it is detected that no foreign matter F is attached to the nozzle guard NG (YES in step S12), the coating process is performed as follows (steps S16 to S24). The substrate 3 is loaded into the coating apparatus 1A (step S16). More specifically, the substrate 3 is placed on the holding surface 41 of the stage 4 and then held by suction.

[0035] Simultaneously, with clean resist liquid adhering to the vicinity of the discharge port 21 due to the pre-dispensing process, the slit nozzle 2 is moved from the pre-dispensing position Ppd to a position above the coating start position Pst (step S17). Subsequently, the slit nozzle 2 begins to descend. The resist liquid adhering to the vicinity of the discharge port 21 of the slit nozzle 2 then comes into contact with the surface 31 of the substrate 3 at the coating start position Ps. As a result, a meniscus of resist liquid is formed on the surface 31 of the substrate 3 at the coating start position Pst. The slit nozzle 2 continues to descend in response to the meniscus formation. Subsequently, the slit nozzle 2 rises by a distance corresponding to the thickness of the resist liquid, adjusting the gap between the discharge port 21 and the surface 31 of the substrate 3, the so-called coating gap (step S18).

[0036] Following the adjustment of the coating gap described above, the coating operation is started (step S19). That is, the slit nozzle 2 moves in the (+Y) direction, and the resist liquid is discharged from its discharge port 21. As a result, the slit nozzle 2 performs a coating operation in which the resist liquid is applied to the surface 31 of the substrate 3, and a coating film of a certain thickness is formed on the surface 31 of the substrate 3. Thus, in this embodiment, the (+Y) direction corresponds to the "relative movement direction" of the present invention.

[0037] The coating operation continues until the substrate 3 is transported to the coating completion position Pen where coating should be finished (step S20). When the substrate 3 reaches the coating completion position Pen (YES in step S20), the discharge of the resist liquid from the slit nozzle 2 is stopped. This terminates the coating operation (step S21). At the same time, the slit nozzle 2 detaches from the coating completion position Pen and returns to the pre-dispense position Ppd (step S22). In parallel with the movement of the slit nozzle 2 to the pre-dispense position Ppd, the suction holding of the substrate 3 is released and the substrate is removed (step S23). If there is another substrate 3 to be processed (YES in step S24), the process returns to step S11 and the same process as above is repeated. On the other hand, if there is no next substrate 3 (NO in step S24), the process is terminated.

[0038] As described above, according to the first embodiment, since the adhesion of foreign matter to the nozzle guard NG is detected before the coating process is performed, it is possible to prevent the coating process from being performed while foreign matter F is attached to the nozzle guard NG. Therefore, defects caused by contact between the substrate 3 and foreign matter F can be reliably prevented, and the coating process can be performed with high quality.

[0039] Furthermore, if foreign matter is detected adhering to the nozzle guard NG, a message prompting the user to clean the nozzle guard NG is immediately displayed on the display unit. Therefore, accurate instructions are displayed to the user in the shortest possible time. When the user notices this and cleans the nozzle guard NG, the coating process can be resumed in a short time without being affected by the foreign matter F. As a result, the operating rate of the coating device 1A can be increased.

[0040] Furthermore, the timing of the foreign object detection process is basically arbitrary, as long as it is performed before the next coating process on the substrate. However, in this embodiment, the foreign object detection process and the pre-dispensing process are performed in parallel by matching the distance D1 between the discharge port 21 of the slit nozzle 2 and the nozzle guard NG with the distance D2 between the pre-dispensing roller 72 and the foreign object detection unit 8 in the Y direction. Thus, in this embodiment, a novel configuration is adopted in which a foreign object detection process is combined with a coating apparatus that performs a pre-dispensing process, but the cycle time does not increase by the takt time required for the foreign object detection process due to the addition of the foreign object detection process. As in the above embodiment, by completing the foreign object detection process while the pre-dispensing process is being performed, it is possible to obtain the above-mentioned effects without changing the cycle time. Also, even if the foreign object detection process is performed before or after the pre-dispensing process, it is possible to obtain the above-mentioned effects while suppressing an increase in cycle time by performing the foreign object detection process in partial parallel with the pre-dispensing process.

[0041] Furthermore, in this embodiment, as shown in Figure 2, the foreign object detection unit 8 is positioned in the space between the nozzle cleaning standby unit 7 and the nozzle cleaning unit 9. Therefore, by effectively utilizing the above space, it is possible to add a new foreign object detection unit 8 while suppressing an increase in the size of the device.

[0042] Furthermore, in this embodiment, foreign objects are detected based on the light-shielding status of the parallel light beam. In other words, since foreign object detection is performed using a non-contact method, foreign object detection can be performed without damaging the nozzle guard NG. As this non-contact method of foreign object detection, the foreign object detection method described below may be employed (second embodiment, third embodiment).

[0043] Thus, in the first embodiment, the nozzle cleaning standby unit 7 corresponds to an example of the "pre-discharge unit" of the present invention. Furthermore, the foreign matter detection unit 8 is located in front of the nozzle cleaning standby unit 7 in the relative movement direction (+Y), and corresponds to an example of the "detection unit" of the present invention. In addition, steps S11 and S19 correspond to examples of the "detection process" and "coating process" of the present invention, respectively.

[0044] Figure 6 schematically shows the foreign matter detection operation in a coating apparatus, which is a second embodiment of the substrate processing apparatus according to the present invention. The main difference between this second embodiment and the first embodiment is that, instead of utilizing the shielding of a parallel light beam, it utilizes the projected image of the tip of the nozzle guard NG. Note that the other components are the same as those of the first embodiment, so the same reference numerals are used for the same components and their descriptions are omitted.

[0045] As shown in Figure 6, in the second embodiment, the foreign object detection unit 8 has a light emitter 85 incorporating an LED and a light-emitting telecentric lens, and a light receiver 86 incorporating a light-receiving telecentric lens and a CMOS sensor, and is capable of acquiring a projected image of the tip of the nozzle guard NG located between the light emitter 85 and the light receiver 86. The image signal corresponding to the projected image acquired by the foreign object detection unit 8 is supplied to the control unit 10. This imaging operation is performed in response to the movement of the foreign object detection unit 8 in the X direction, and as shown in Figure 6, projected images at sensor positions P(X1), ..., P(Xn), ..., P(Xmax) are sequentially acquired and temporarily stored in the memory unit of the control unit 10. For example, the TM-X5000 series inline projection image measuring instrument manufactured by Keyence Corporation can be used as the foreign object detection unit 8.

[0046] Based on the projection image obtained in this way, the calculation unit of the control unit 10 determines whether or not foreign matter F (Figure 4) is attached to the nozzle guard NG. For example, when a projection image like the one shown in Figure 6 is obtained, when the foreign matter detection unit 8 moves over a position on the tip of the nozzle guard NG where no foreign matter is attached (a position other than position P(Xn) in the same figure), the projection image contains only the ridge image IMa corresponding to the tip of the nozzle guard NG and the tip side image IMb extending upward from the ridge image IMa. In contrast, when the foreign matter detection unit 8 moves over a position where foreign matter F is attached (position P(Xn) in the same figure), the projection image contains not only the ridge image IMa and the tip side image IMb, but also a foreign matter image IMc corresponding to foreign matter F. Therefore, by determining whether or not the projection image contains the foreign matter image IMc, the control unit 10 can identify the presence or absence of foreign matter F and the location where foreign matter F is attached.

[0047] As described above, in the second embodiment, foreign matter is detected on the nozzle guard NG based on a projected image of the tip of the nozzle guard NG before the coating process is performed, so the same effects and advantages as in the first embodiment can be obtained.

[0048] Furthermore, in the second embodiment, the shape and size of the foreign object F can be detected from the projected image, thus enabling more accurate foreign object detection than in the first embodiment. For example, if the amount of protrusion from the edge image IMa to the foreign object image IMc is small enough not to affect the coating operation, the system may be configured to determine in step S12 that no foreign object has been detected and proceed to the coating operation. This increases the operating rate of the coating apparatus 1A.

[0049] Figure 7 is a schematic diagram showing the foreign object detection operation in a coating apparatus, which is a third embodiment of the substrate processing apparatus according to the present invention. The main difference between this third embodiment and the first embodiment is that the foreign object detection unit 8 is composed of a line scan camera. In comparison with the second embodiment, while the second embodiment detects foreign objects F by capturing a projected image, in this embodiment, the tip of the nozzle guard NG positioned at the foreign object detection position Pdt is captured from below. The image signal corresponding to the image acquired by the line scan camera is provided to the control unit 10. This imaging operation is performed in response to the movement of the foreign object detection unit 8 in the X direction, and as shown in Figure 7, images at sensor positions P(X1), ..., P(Xn), ..., P(Xmax) are sequentially acquired and temporarily stored in the memory unit of the control unit 10.

[0050] Based on the image obtained in this way, the calculation unit of the control unit 10 determines whether or not foreign matter F (Figure 4) is attached to the nozzle guard NG. For example, when a tip surface image as shown in Figure 7 is acquired, when the foreign matter detection unit 8 moves over a position on the tip of the nozzle guard NG where no foreign matter is attached (a position other than position P(Xn) in the same figure), the tip surface image includes only the tip surface image IMd, which is a view of the tip of the nozzle guard NG from below. In contrast, when the foreign matter detection unit 8 moves over a position where foreign matter F is attached (position P(Xn) in the same figure), the image includes not only the tip surface image IMd but also a foreign matter image IMe corresponding to the foreign matter F. Therefore, by determining whether or not the tip surface image includes the foreign matter image IMe, the control unit 10 can identify the presence or absence of foreign matter F and the location where foreign matter F is attached.

[0051] As described above, in the third embodiment, since foreign matter is detected on the nozzle guard NG based on the tip surface image of the nozzle guard NG before performing the coating process, not only are the same effects as in the first embodiment obtained, but the same effects as in the second embodiment can also be obtained.

[0052] Figure 8 is a schematic side view showing a coating apparatus, which is a fourth embodiment of the substrate processing apparatus according to the present invention. The main difference between the fourth embodiment and the first embodiment is that the fourth embodiment further includes a guard cleaning unit 11 as an example of a foreign matter removal unit for removing foreign matter adhering to the nozzle guard NG. Note that the other components are the same as those of the first embodiment, so the same reference numerals are used for the same components and their descriptions are omitted.

[0053] For example, the guard cleaning unit 11 described in Japanese Patent Publication No. 2022-134204 can be used. This guard cleaning unit 11 is located at a guard cleaning position Pgc, which is a distance D3 (+Y) away from the nozzle cleaning unit 9. In this embodiment, this distance D3 coincides with the distance D1 from the discharge port 21 of the slit nozzle 2 to the nozzle guard NG in the Y direction. Therefore, when the slit nozzle 2 is positioned at the nozzle cleaning position Pnc corresponding to the scraper (contact member) 91 in order to clean the tip of the slit nozzle 2 with the nozzle cleaning unit 9, the tip of the nozzle guard NG is positioned at the guard cleaning unit 11, and the guard cleaning process can be performed in parallel with the nozzle cleaning process.

[0054] The tip of the slit nozzle 2 is cleaned at the time the coating device 1A is started, after each coating process is completed, after a predetermined number of coating processes have been performed, and when a nozzle cleaning request is received from the user. In other words, the control unit 10 controls each part of the device to move the slit nozzle 2 to the nozzle cleaning unit 9 and perform the nozzle cleaning process. This movement positions the nozzle guard NG to the guard cleaning unit 11. In the fourth embodiment, the guard cleaning process is configured to be performed in parallel with the nozzle cleaning process. In this fourth embodiment, although the configuration of performing guard cleaning in addition to nozzle cleaning is adopted, the cycle time does not increase by the takt time required for the guard cleaning process due to the addition of the guard cleaning process. Furthermore, by completing the guard cleaning process while the nozzle cleaning process is being performed, it is possible to obtain the above-mentioned effects without changing the cycle time. Also, even if the guard cleaning process extends beyond the time of the nozzle cleaning process, it is possible to obtain the above-mentioned effects while suppressing an increase in cycle time by performing the guard cleaning process in parallel with a part of the nozzle cleaning process.

[0055] Furthermore, since the fourth embodiment has a guard cleaning unit 11, when foreign matter F is detected in step S12, instead of notifying the user of a cleaning request for the nozzle guard NG, the system may be configured to automatically execute the guard cleaning process. In other words, when the control unit 10 detects foreign matter adhering to the nozzle guard NG (NO in step S12), it interrupts the coating process in step S13. Subsequently, the control unit 10 may be configured to position the nozzle guard NG in the guard cleaning unit 11 and then clean the nozzle guard NG with the guard cleaning unit 11. The control unit 10 may also control each part of the device to perform the nozzle cleaning process in parallel with the cleaning of the nozzle guard NG.

[0056] By the way, in the fourth embodiment described above, a guard cleaning unit 11 described in Japanese Patent Application Publication No. 2022-134204 is used as an example of a foreign matter removal unit that removes foreign matter (reference numeral F in Figure 4) adhering to the tip of the nozzle guard NG, but the following problems exist. This guard cleaning unit 11 is movable in the X direction along the tip (lower end) of the nozzle guard NG while supplying nitrogen gas and rinse liquid to the nozzle guard NG. The guard cleaning unit 11 is also moved back and forth in the extending direction X of the nozzle guard NG by a moving mechanism which is not shown. The tip of the nozzle guard NG enters into a roughly V-shaped space provided in the upper center of the guard cleaning unit 11, and the nozzle guard NG is cleaned as the guard cleaning unit 11 moves in the X direction while nitrogen gas and rinse liquid are supplied to the tip.

[0057] In this manner, the guard cleaning unit 11 cleans and removes foreign matter adhering to the nozzle guard NG using a wet method. Therefore, after the cleaning process of the nozzle guard NG, rinse liquid may remain on the nozzle guard NG, and if the nozzle guard NG moves upward towards the substrate 3 together with the slit nozzle 2 in this state, it may fall onto the surface 31 of the substrate 3 just before coating. If the surface 31 of the substrate 3 becomes wet with rinse liquid in this way, not only will the coating process not be performed properly, but it may also cause process defects afterward.

[0058] Therefore, as a foreign matter removal unit for removing foreign matter F, instead of the guard cleaning unit 11 adopted in the fourth embodiment, a dry foreign matter removal unit that removes foreign matter F from the nozzle guard NG in a so-called dry manner may be provided (fifth to eleventh embodiments). The configuration and operation of the dry foreign matter removal unit in the fifth to eleventh embodiments will be described in order below.

[0059] Figure 9 is a schematic diagram showing the operation of a dry guard cleaner, which is an example of a foreign matter removal unit equipped in a coating apparatus, which is a fifth embodiment of the substrate processing apparatus according to the present invention. Figure 10 is a schematic diagram showing the operation of the dry guard cleaner shown in Figure 9. The dry guard cleaner 12 is positioned at a guard cleaning position Pgc, which is located at a distance D3 (+Y) away from the nozzle cleaning unit 9. In this embodiment, this distance D3 coincides with the distance D1 from the discharge port 21 of the slit nozzle 2 to the nozzle guard NG in the Y direction. Therefore, when the slit nozzle 2 is positioned at the nozzle cleaning position Pnc corresponding to the scraper (contact member) 91 in order to clean the tip of the slit nozzle 2 with the nozzle cleaning unit 9, the tip of the nozzle guard NG is positioned at the dry guard cleaner 12 configured as described below, and the dry guard cleaning process can be performed in parallel with the nozzle cleaning process.

[0060] As shown in Figures 9 and 10, the dry guard cleaner 12 has two adhesive rollers 121 and 122. The adhesive rollers 121 and 122 are roller bodies that can rotate around rotation axes 121b and 122b extending in the X direction, respectively, and have adhesive layers 121a and 122a fixedly provided on their surfaces at the guard cleaning position Pgc.

[0061] The adhesive roller 121 is rotatably positioned in contact with the tip (lower end) of the nozzle guard NG, which is positioned at the guard cleaning position Pgc. On the other hand, the adhesive roller 122 is positioned on the opposite side of the nozzle guard NG (in this embodiment, the (-Z) direction side) with the adhesive roller 121 in between. The adhesive roller 122 is provided to rotate freely in a direction opposite to the rotation direction of the adhesive roller 121 while in contact with the adhesive roller 121. Furthermore, in this embodiment, the materials constituting the adhesive layers 121a and 122a are selected such that the adhesive force to foreign matter F is higher in the adhesive layer 122a than in the adhesive layer 121a.

[0062] The dry guard cleaner 12 configured in this way is connected to the roller drive unit 123. Therefore, when the roller drive unit 123 operates in response to a roller rotation command from the control unit 10, the dry guard cleaner 12 rotates around the first rotation axis 121b in the longitudinal direction X of the nozzle guard NG, with the adhesive layer 121a of the adhesive roller 121 in contact with the entire tip of the nozzle guard NG. The other adhesive roller 122 is in close contact with the entire adhesive roller 121 in the longitudinal direction X of the nozzle guard NG, below the contact position between the adhesive roller 121 and the nozzle guard NG (vertically downward in this embodiment). Moreover, the roller drive unit 123 rotates the adhesive roller 122 counterclockwise in the plane of the paper in Figure 10.

[0063] Here, for example, if foreign matter F is attached to the tip of the nozzle guard NG at position P(n), the foreign matter F is removed from the nozzle guard NG at position P(n) by the operation shown in Figure 10. In other words, when foreign matter removal is performed, the rotation of the adhesive rollers 121 and 122 begins, and the nozzle guard NG is moved to the guard cleaning position Pgc. When its tip comes into contact with the rotating adhesive roller 121, the foreign matter F is transferred to the first adhesive layer 121a. Through this transfer, the foreign matter F is captured by the adhesive layer 121a and removed from the nozzle guard NG. After this foreign matter removal is completed, the nozzle guard NG moves away from the adhesive roller 121. Meanwhile, even after the nozzle guard NG has moved away, the adhesive rollers 121 and 122 continue to rotate for a certain period of time. As a result, the foreign matter F moves to the nip position where the adhesive rollers 121 and 122 are in close contact with each other. Then, at the nip position, the foreign object F is transferred from the adhesive roller 121 to the adhesive roller 122. In this embodiment, since the adhesive force of the adhesive layer 122a is stronger than the adhesive force of the adhesive layer 121a, the transfer of the foreign object F from the adhesive roller 121 to the adhesive roller 122 is ensured. As a result, the adhesive roller 121 does not carry the foreign object F and is returned to a state in which it can effectively capture another foreign object F, and rotates clockwise.

[0064] Figure 11 is a schematic diagram showing the operation of a dry guard cleaner, which is an example of a foreign matter removal unit equipped in a coating apparatus, which is the sixth embodiment of the substrate processing apparatus according to the present invention. Figure 12 is a schematic diagram showing the operation of the dry guard cleaner shown in Figure 11. The main difference between this sixth embodiment and the fifth embodiment is the structure of the dry guard cleaner 12. In the fifth embodiment, adhesive rollers 121 and 122 fixedly positioned at the guard cleaning position Pgc are used. In contrast, the sixth embodiment uses movable adhesive rollers 121 and 122. In the following, the configuration and operation of the dry guard cleaner 12 will be described in detail, and identical components and operations will be denoted by the same reference numerals and their descriptions will be omitted.

[0065] In the sixth embodiment, the dry guard cleaner 12 has two adhesive rollers 121 and 122, as shown in Figures 10 and 11, and is similar to the first embodiment in that adhesive layers 121a and 122a are provided on the surface of the roller bodies. On the other hand, both adhesive rollers 121 and 122 are significantly shorter than those in the fifth embodiment, and their rotation axes 121b and 122b are arranged to be parallel to the Y direction. Furthermore, the adhesive rollers 121 and 122 are integrally capable of reciprocating in the X direction.

[0066] The adhesive roller 121 is configured to rotate freely in the X direction while in contact with the tip (lower end) of the nozzle guard NG, which is positioned at the guard cleaning position Pgc. On the other hand, the adhesive roller 122 is positioned on the opposite side of the nozzle guard NG (in this embodiment, the (-Z) direction side) with the adhesive roller 121 in between. The adhesive roller 122 is provided to rotate freely in a direction opposite to the rotation direction of the adhesive roller 121 while in contact with the adhesive roller 121. Furthermore, in this embodiment, the materials constituting the adhesive layers 121a and 122a are selected such that the adhesive force to foreign matter F is higher in the adhesive layer 122a than in the adhesive layer 121a.

[0067] The dry guard cleaner 12 is connected to the roller drive unit 123. Therefore, when the roller drive unit 123 is activated in response to a movement command from the control unit 10, the dry guard cleaner 12 moves in the X direction with the adhesive layer 121a of the adhesive roller 121 in contact with the tip of the nozzle guard NG, forming a nip portion NP (Figure 11), as shown in Figures 10 and 11. The adhesive roller 121 rolls between the front position P (X1) and the back position P (Xmax) while rotating clockwise in the plane of Figure 11. The other adhesive roller 122 moves integrally with the adhesive roller 121 between the front position P (X1) and the back position P (Xmax) while rotating counterclockwise in the plane of Figure 11, while maintaining close contact with the adhesive roller 121 below the nip portion NP (vertically downward in this embodiment). In Figure 11 (and Figure 11 explained later), the symbol P(X0) represents the first retraction position located in the (+X) direction from the front position P(X1), and the symbol P(Xmax+1) represents the second retraction position located in the (-X) direction from the rear position P(Xmax).

[0068] Here, for example, if foreign matter F is attached to position P(n) at the tip of the nozzle guard NG, the foreign matter F is transferred from the nozzle guard NG to the adhesive layer 121a as the adhesive roller 121 rolls and passes over position P(n). Through this transfer, the foreign matter F is captured by the adhesive layer 121a and removed from the nozzle guard NG. The removed foreign matter F, while still captured by the adhesive layer 121a, moves clockwise integrally with the adhesive roller 121 and separates from the nozzle guard NG. When the foreign matter F moves to the nip position where the adhesive rollers 121 and 122 are in close contact with each other, the foreign matter F is transferred from the adhesive roller 121 to the adhesive roller 122. Here, in this embodiment, since the adhesive force of the adhesive layer 122a is stronger than the adhesive force of the adhesive layer 121a with respect to the foreign matter F, the transfer of a portion of F from the adhesive roller 121 to the adhesive roller 122 is reliably performed. As a result, the adhesive roller 121 is returned to a state where it does not carry foreign matter F and can effectively capture other foreign matter F, and rotates clockwise.

[0069] In the fifth and sixth embodiments described above, the dry guard cleaner 12 has adhesive rollers 121 and 122. However, it may also be composed of only the adhesive roller 121, which is responsible for directly removing foreign matter F from the nozzle guard NG. In this case, it is desirable to perform maintenance work such as replacing the adhesive roller 121 or cleaning it each time the removal of foreign matter progresses to a certain extent. Considering this maintenance frequency, the fifth and sixth embodiments described above are superior to the modified form composed of only the adhesive roller 121.

[0070] Figure 13 is a schematic perspective view showing the configuration and operation of a dry guard cleaner, which is an example of a foreign matter removal unit equipped in a coating apparatus, which is the seventh embodiment of the substrate processing apparatus according to the present invention. Figure 14 is a schematic diagram showing the operation of the dry guard cleaner shown in Figure 13. The main difference between this seventh embodiment and the fifth embodiment is the structure of the dry guard cleaner 12. In the fifth embodiment, the dry guard cleaner 12 is configured with two upper and lower adhesive rollers 121 and 122, whereas in the seventh embodiment, the dry guard cleaner 12 is configured to capture and remove foreign matter F by transferring it using adhesive tape. Note that the other configurations are the same as in the fifth embodiment, so the same reference numerals are used for the same components and their descriptions are omitted.

[0071] In the seventh embodiment, the dry guard cleaner 12 has a tape supply unit 125, a tape recovery unit 126, and a backup roller 127 fixedly arranged at the guard cleaning position Pgc. These tape supply unit 125, tape recovery unit 126, and backup roller 127 are rotatably mounted around a rotation axis extending in the X direction parallel to the longitudinal direction of the nozzle guard NG. In the tape supply unit 125, as shown in Figure 14, an adhesive tape 128 having an adhesive layer on its surface is wound around the supply roller body 125a. As shown in Figure 13, this adhesive tape 128 has an adhesive layer on its surface and has a width that allows it to contact the entire nozzle guard NG in the longitudinal direction X of the nozzle guard NG. The adhesive tape 128 pulled out from the tape supply unit 125 is sent to the tape recovery unit 126 with its back surface stretched over the backup roller 127, which is positioned above the tape supply unit 125 and the tape recovery unit 126, and is wound up onto the recovery roller body 126a of the tape recovery unit 126 for recovery. The backup roller 127 is longer than the nozzle guard NG in the X direction and is positioned opposite to the nozzle guard NG so as to cover the entire nozzle guard NG from below, with the adhesive tape 128 in between. The backup roller 127 is supplied from the tape supply unit 125 and, before being collected by the tape recovery unit 126, presses the nozzle guard NG against the surface of the adhesive tape 128, i.e., the surface of the adhesive layer (adhesive layer), in the width direction of the nozzle guard NG. This forms a nip portion NP between the nozzle guard NG and the backup roller 127. Foreign matter F adhering to the nozzle guard NG is transferred to the adhesive layer at this nip portion NP.

[0072] The supply roller 125a and the retrieval roller 126a are connected to the tape drive motor (not shown) of the tape running section 129. When this tape drive motor rotates in response to a command from the control unit 10, the adhesive tape 128 is pulled out diagonally upward from the tape supply section 125 and sent to the backup roller 127 with the adhesive layer facing upward. The adhesive tape 128, stretched over the backup roller 127, then comes into close contact with the nozzle guard NG to form a nip portion NP. At this nip portion NP, foreign matter F is transferred from the nozzle guard NG to the adhesive tape 128. After that, the adhesive tape 128 is retrieved while still carrying the transferred foreign matter F.

[0073] Figure 15 is a schematic perspective view showing the configuration and operation of a dry guard cleaner, which is an example of a foreign matter removal unit equipped in a coating apparatus, which is the eighth embodiment of the substrate processing apparatus according to the present invention. Figure 16 is a schematic diagram showing the operation of the dry guard cleaner shown in Figure 15. The main difference between this eighth embodiment and the seventh embodiment is the structure of the dry guard cleaner 12. In the seventh embodiment, the tip of the nozzle guard NG is brought into overall contact with the adhesive tape 128 that runs in the order of tape supply unit 125, backup roller 127, and tape recovery unit 126, thereby removing foreign matter F attached to the nozzle guard NG all at once.

[0074] In contrast, in the eighth embodiment, the tape supply unit 125, tape retrieval unit 126, and backup roller 127 are rotatable around a rotation axis parallel to the relative movement direction Y, and their lengths in the Y direction are significantly shorter compared to those in the seventh embodiment. A nip transfer unit 130 is connected to these tape supply unit 125, tape retrieval unit 126, and backup roller 127. Similar to the seventh embodiment, the nip transfer unit 130 has a tape running unit (not shown) for running the adhesive tape 128 and a moving unit (not shown) for moving the tape supply unit 125, tape retrieval unit 126, and backup roller 127 together in the X direction, making it possible to move the nip portion NP along the nozzle guard NG as will be described below.

[0075] As described above, because the Y-direction lengths of the tape supply unit 125, tape recovery unit 126, and backup roller 127 are short, the adhesive tape 128 has a significantly narrower width than in the seventh embodiment. The adhesive tape 128 runs in the order of tape supply unit 125, backup roller 127, and tape recovery unit 126. The backup roller 127 presses the adhesive tape 128 against a part of the tip of the nozzle guard NG to form a nip portion NP. Furthermore, the tape supply unit 125, backup roller 127, and tape recovery unit 126 move integrally in the X direction. As a result, the nip portion NP moves along the tip of the nozzle guard NG, and consequently, foreign matter F adhering to the nozzle guard NG is sequentially transferred to the adhesive tape 128, and the adhesive tape 128 is recovered while carrying the transferred foreign matter F. In this way, the dry guard cleaning process is completed as the nip portion NP moves from one end to the other of the tip of the nozzle guard NG.

[0076] Figure 17 is a perspective view showing the overall configuration and operation of a dry guard cleaner, which is an example of a foreign matter removal unit equipped in a coating apparatus, which is the ninth embodiment of the substrate processing apparatus according to the present invention. Figure 18 is a schematic diagram showing the operation of the dry guard cleaner shown in Figure 17. The dry guard cleaner 12 is positioned at a guard cleaning position Pgc, which is located at a distance D3 (+Y) away from the nozzle cleaning unit 9. In this embodiment, this distance D3 coincides with the distance D1 from the discharge port 21 of the slit nozzle 2 to the nozzle guard NG in the Y direction. Therefore, when the slit nozzle 2 is positioned at the nozzle cleaning position Pnc corresponding to the scraper (contact member) 91 in order to clean the tip of the slit nozzle 2 with the nozzle cleaning unit 9, the tip of the nozzle guard NG is positioned at the dry guard cleaner 12 configured as described below, and the dry guard cleaning process can be performed in parallel with the nozzle cleaning process.

[0077] The dry guard cleaner 12 has a suction head 120. As shown in Figure 18, the upper part of the suction head 120 has a roughly V-shaped YZ cross-section so as to cover the surrounding atmosphere SA from below the tip (lower end) of the nozzle guard NG positioned at the guard cleaning position Pgc. In Figure 18, dots are added to visually indicate the surrounding atmosphere SA.

[0078] The suction head 120 is mounted to be movable along the nozzle guard NG in the longitudinal direction X, while viewing the surrounding atmosphere SA of the nozzle guard NG from below. A groove extending in the X direction is formed in the center of the upper part of the suction head 120. Multiple suction ports are provided in this groove. The suction head 120 is connected to a head movement unit 120h. A suction unit 120a is also connected to the suction head 120. Therefore, when the head movement unit 120h and the suction unit 120a are activated by a command from the control unit 10, the suction head 120 moves in the longitudinal direction X of the nozzle guard NG while sucking the surrounding atmosphere SA of the nozzle guard NG. In other words, the suction head 120 moves in the X direction along the tip of the nozzle guard NG while applying negative pressure to the tip of the nozzle guard NG. For example, as shown in Figure 18, the foreign matter F is removed from the nozzle guard NG by the suction head 120 as it passes over the location where the foreign matter F is attached (foreign matter removal process).

[0079] Figure 19 is a schematic diagram showing the configuration and operation of a foreign matter removal unit equipped in a coating apparatus, which is the tenth embodiment of the substrate processing apparatus according to the present invention. The main difference between this tenth embodiment and the ninth embodiment is the structure of the dry guard cleaner 12. In the ninth embodiment, the suction head 120 is shorter than the nozzle guard NG in the X direction, and foreign matter F is sucked and removed from the entire nozzle guard NG by moving the suction head 120 in the X direction. In contrast, in the tenth embodiment, the length of the suction head 120 in the X direction is the same as or longer than the nozzle guard NG, and a substantially V-shaped portion 120b extends in the X direction over the entire suction head 120. The substantially V-shaped portion 120b makes it possible to cover the surrounding atmosphere SA (Figure 6) of the tip (lower end) of the nozzle guard NG from below. This suction head 120 is fixedly positioned at the guard cleaning position Pgc. Note that the other configurations are the same as in the ninth embodiment, so the same reference numerals are used for the same components and their descriptions are omitted.

[0080] In the tenth embodiment, as shown by the dashed line in the figure, the slit nozzle 2 and the nozzle guard NG are moved integrally in the (+Y) direction, and when the nozzle guard NG is positioned in the guard cleaning position Pgc, the entire surrounding atmosphere around the tip of the nozzle guard NG is covered from below by the substantially V-shaped portion 120b. In this state, when the suction unit 120a is activated in response to a command from the control unit 10, the entire surrounding atmosphere becomes a negative pressure, and the foreign matter F adhering to the tip of the nozzle guard NG is collectively sucked and removed by the suction unit 120a.

[0081] Figures 20A and 20B schematically show the configuration and operation of a foreign matter removal unit equipped in a coating apparatus, which is the 11th embodiment of the substrate processing apparatus according to the present invention. The main differences between this 11th embodiment and the 10th embodiment are the addition of a brush member 120c to the upper surface of the suction head 120 and the use of brush cleaning with the brush member 120c in combination. Note that the other configurations are the same as those of the 10th embodiment, so the same reference numerals are used for the same components and their descriptions are omitted.

[0082] In this embodiment, brush members 120c, 120c are erected on the (+Y) and (-Y) ends of the substantially V-shaped portion 120b on the upper surface of the suction head 120, facing the nozzle guard NG. As shown by the dashed line in Figure 20A, when the slit nozzle 2 and nozzle guard NG are moved integrally in the (+Y) direction and the nozzle guard NG is positioned in the guard cleaning position Pgc, the entire surrounding atmosphere around the tip of the nozzle guard NG is covered from below by the substantially V-shaped portion 120b. At the same time, the tops of the brush members 120c, 120c are positioned so as to overlap with the tip of the nozzle guard NG in the Z direction. In this state, the slit nozzle 2 and nozzle guard NG swing integrally in the Y direction in response to a swing command from the control unit 10 (see symbol AR in Figure 20B). At this time, the tips of the brush members 120c, 120c rub against the tip of the nozzle guard NG, and brush cleaning is performed. This process removes foreign matter F from the nozzle guard NG. In parallel with this brush cleaning, the suction unit 120a operates in response to a command from the control unit 10, and the foreign matter F is removed all at once by the suction unit 120a. Therefore, the foreign matter F removed from the nozzle guard NG by brush cleaning can be reliably removed by suction, and the scattering of the foreign matter F around the guard cleaning position Pgc can be reliably prevented.

[0083] By the way, in the first to eleventh embodiments described above, the present invention is applied to a coating apparatus 1A in which a slit nozzle 2 moves relative to a substrate 3 to apply a resist solution (processing solution). However, as described in Patent Document 2, the present invention can also be applied to a coating apparatus in which a substrate moves relative to a fixedly positioned slit nozzle to apply a resist solution (processing solution). The tenth embodiment of the present invention will be described below with reference to Figure 21.

[0084] Figure 21 is a schematic diagram showing the overall configuration of a coating apparatus, which is the tenth embodiment of the substrate processing apparatus according to the present invention. This coating apparatus 1B is a slit coater that coats the surface 31 of a substrate 3, which is transported in a horizontal position from the left side to the right side in Figure 21, with a resist liquid (processing liquid). In order to clarify the arrangement of each part of the apparatus in Figure 21, a right-handed XYZ orthogonal coordinate system is set as shown in the figure. The transport direction of the substrate 3 is referred to as the "X direction," the horizontal direction from the left side to the right side in Figure 21 is referred to as the "+X direction," and the opposite direction is referred to as the "-X direction." In addition, of the horizontal direction Y perpendicular to the X direction, the front side of the apparatus (the side closer to the viewer in the figure) is referred to as the "-Y direction," and the back side of the apparatus is referred to as the "+Y direction." Furthermore, the upward and downward directions in the vertical direction Z are referred to as the "+Z direction" and the "-Z direction," respectively.

[0085] In the coating apparatus 1B, the input conveyor 100, input transfer unit 200, floating unit 300, output transfer unit 400, and output conveyor 110 are arranged in close proximity in this order along the transport direction Dt of the substrate 3, i.e., the (+X direction). As will be described in detail below, these components form a transport path for the substrate 3 that extends in a substantially horizontal direction.

[0086] The substrate 3 to be processed is brought into the input conveyor 100 from the left side in Figure 21. The input conveyor 100 is equipped with a roller conveyor 101 and a rotational drive mechanism 102 that rotates it. The rotation of the roller conveyor 101 transports the substrate 3 in a horizontal position downstream, i.e., in the (+X) direction. The input transfer unit 200 is equipped with a roller conveyor 221 and a rotation / lifting drive mechanism 222 that has the function of rotating and lifting the roller conveyor. As the roller conveyor 221 rotates, the substrate 3 is transported further in the (+X) direction. Also, as the roller conveyor 221 is raised and lowered, the vertical position of the substrate 3 is changed. With the input transfer unit 200 configured in this way, the substrate 3 is transferred from the input conveyor 100 to the floating unit 300.

[0087] The levitation section 300 includes an upstream levitation stage 301, a central levitation stage 302, and a downstream levitation stage 303. Both the upstream levitation stage 301 and the downstream levitation stage 303 have numerous air ejection holes formed in a matrix pattern distributed across the entire surface of a single plate-shaped stage. Compressed air is supplied to each ejection hole, and the gas flow caused by the ejection of compressed air from each ejection hole levitates the substrate 3. As a result, in the upstream levitation stage 301 and the downstream levitation stage 303, the substrate 3 floats above the stage surface to a predetermined levitation height, for example, 10 to 500 micrometers. A levitation control mechanism 335 is provided to supply compressed air to each ejection hole, as shown in Figure 21.

[0088] Furthermore, the downstream levitation stage 303 has multiple lift pins in addition to the ejection holes. A lift pin drive mechanism 334 is provided to raise and lower the lift pins. The multiple lift pins are arranged at predetermined intervals between the ejection holes so as to face each other across the entire back surface of the substrate 3. The lift pins are driven to move up and down vertically (in the Z-axis direction) by the lift pin drive mechanism 334 installed below the stage surface. In other words, when lowering, the tips of the lift pins move down in the (-Z) direction relative to the stage surface of the downstream levitation stage 303, and when raising, the tips of the lift pins rise to a position where the substrate 3 can be handed over to a transfer robot (not shown). The lower surface of the substrate 3 is supported and lifted by the raised lift pins, so that the substrate 3 rises above the stage surface of the downstream levitation stage 303. This makes it possible for the transfer robot to unload the substrate 3 from the coating device 1B.

[0089] On the other hand, the central levitation stage 302 is configured as follows and has higher levitation accuracy than the upstream levitation stage 301 and the downstream levitation stage 303. Specifically, the central levitation stage 302 has a rectangular plate-like stage surface. Multiple holes are provided on this stage surface in a matrix-like arrangement with a narrower pitch than the ejection holes provided on the upstream levitation stage 301 and the downstream levitation stage 303. Also, unlike the upstream levitation stage 301 and the downstream levitation stage 303, in the central levitation stage 302, half of the holes function as compressed air ejection holes, and the other half function as suction holes. In other words, compressed air is ejected from the ejection holes toward the back surface of the substrate 3 and sent into the space between the stage surface and the back surface of the substrate 3. Meanwhile, air is drawn in from the space through the suction holes. As air is ejected and sucked into the space described above, the compressed air flow ejected from each ejection hole spreads horizontally within the space and is then sucked in from the suction hole adjacent to the ejection hole. This stabilizes the pressure balance in the air layer (pressure gas layer) that spreads within the space, allowing for highly accurate and stable control of the levitation height of the substrate 3. The supply of compressed air to each ejection hole and the sucking of air from the suction hole are controlled by the levitation control mechanism 335.

[0090] The substrate 3, which is transported to the levitation section 300 via the input transfer section 200, is propelled in the (+X) direction by the rotation of the roller conveyor 221 and transported onto the upstream levitation stage 301. The upstream levitation stage 301, the central levitation stage 302, and the downstream levitation stage 303 support the substrate 3 in a levitated state, but do not have the function of moving the substrate 3 horizontally. Transport of the substrate 3 in the levitation section 300 is carried out by the substrate transport section 500 located below the upstream levitation stage 301, the central levitation stage 302, and the downstream levitation stage 303.

[0091] The substrate transport section 500 includes a chuck mechanism 551 that supports the substrate 3 from below by partially contacting the lower peripheral edge of the substrate 3, and a suction / travel control mechanism 552 that has the function of applying negative pressure to a suction pad (not shown) provided on the suction member at the upper end of the chuck mechanism 551 to suction and hold the substrate 3, and the function of causing the chuck mechanism 551 to reciprocate in the X direction. When the chuck mechanism 551 holds the substrate 3, the back surface of the substrate 3 is located higher than the surface of each stage of the floating section 300. Therefore, the substrate 3 maintains a horizontal posture overall due to the buoyancy applied from the floating section 300 while its peripheral edge is suction and held by the chuck mechanism 551. A plate thickness measuring sensor SN is positioned near the roller conveyor 221 to detect the vertical position of the surface of the substrate 3 when the back surface of the substrate 3 is partially held by the chuck mechanism 551. By positioning a chuck (not shown) that is not holding the substrate 3 directly below the sensor SN, the sensor SN can detect the vertical position of the surface of the adsorption member, i.e., the adsorption surface.

[0092] The substrate 3, which has been transported from the input transfer unit 200 to the levitation unit 300, is held by the chuck mechanism 551. In this state, the chuck mechanism 551 moves in the (+X) direction, transporting the substrate 3 from above the upstream levitation stage 301, through above the central levitation stage 302, to above the downstream levitation stage 303. The transported substrate 3 is then handed over to the output transfer unit 400 located on the (+X) side of the downstream levitation stage 303.

[0093] The output transfer unit 400 includes a roller conveyor 441 and a rotation / lifting drive mechanism 442 that has the function of rotating and raising / lowering the roller conveyor 441. As the roller conveyor 441 rotates, a thrust force in the (+X) direction is applied to the substrate 3, and the substrate 3 is further transported along the transport direction Dt. In addition, as the roller conveyor 441 is raised and lowered, the vertical position of the substrate 3 is changed. The output transfer unit 400 transfers the substrate 3 from above the downstream levitation stage 303 to the output conveyor 110.

[0094] The output conveyor 110 comprises a roller conveyor 111 and a rotational drive mechanism 112 that rotates it. The rotation of the roller conveyor 111 further transports the substrate 3 in the (+X) direction, and it is finally discharged outside the coating apparatus 1B. The input conveyor 100 and the output conveyor 110 may be provided as part of the configuration of the coating apparatus 1B, but they may also be separate from the coating apparatus 1B. For example, a substrate discharge mechanism of a separate unit provided upstream of the coating apparatus 1B may be used as the input conveyor 100. Alternatively, a substrate receiving mechanism of a separate unit provided downstream of the coating apparatus 1B may be used as the output conveyor 110.

[0095] As described above, a coating mechanism 700 for applying resist liquid to the surface 31 of the substrate 3 is positioned on the transport path of the substrate 3. The coating mechanism 700 has a slit nozzle 2 having the same configuration as in the first embodiment. A nozzle drive mechanism 800 is connected to the slit nozzle 2, as shown in Figure 21, and the nozzle drive mechanism 800 positions the slit nozzle 2 at a coating position above the central floating stage 302 (a position shown by a solid line in Figure 21), an upper position away from the coating position, and a maintenance position. Furthermore, a coating liquid supply mechanism (not shown) is connected to the slit nozzle 2, and resist liquid is supplied from the coating liquid supply mechanism and discharged as processing liquid from a discharge port 21 that opens downward at the bottom of the nozzle.

[0096] The slit nozzle 2 has an outlet 21 that extends in the Y direction and is supported by a nozzle support (not shown) so that it can discharge resist liquid vertically downward (-Z side). The nozzle support is connected to a nozzle drive mechanism 800. In particular, when supplying resist liquid to the surface 31 of the substrate 3 by the slit nozzle 2, the slit nozzle 2 moves to a position above the coating position, as shown by the dashed line in Figure 4, and then descends until the distance (gap) between the outlet 21 and the substrate 3 reaches a predetermined value. This positions the slit nozzle 2 at the coating position. After that, while maintaining this positioning state, the resist liquid is discharged from the outlet 21 toward the surface 31 of the substrate 3, while the substrate 3 is transported in the (+X) direction. In other words, the slit nozzle 2 moves in the (-X) direction relative to the substrate 3 to perform the coating process. In this embodiment, the (-X) direction corresponds to the "relative movement direction" of the present invention. A nozzle guard NG is attached to the front side of the slit nozzle 2 in the relative movement direction (-X).

[0097] To perform predetermined maintenance on the slit nozzle 2 configured in this way, the coating mechanism 700 is provided with a nozzle maintenance unit 6 having the same configuration as in the first embodiment, as shown in Figure 21. Specifically, it has a nozzle cleaning standby unit 7 for performing so-called pre-dipence processing, a foreign matter detection unit 8 for detecting the adhesion of foreign matter to the nozzle guard NG, and a nozzle cleaning unit 9 for cleaning the slit nozzle 2. These are arranged in this order along the relative movement direction (-X). And, as in the first embodiment, before the coating process, the control unit 10 determines whether or not foreign matter (indicated by the symbol F in Figure 4) is adhering to the nozzle guard NG. If the control unit 10 determines that foreign matter is adhering to the nozzle guard NG as a result of this determination, it restricts the coating process and then immediately displays a message on the display unit prompting cleaning of the nozzle guard NG.

[0098] As described above, in the tenth embodiment, as in the first embodiment, the adhesion of foreign matter to the nozzle guard NG is detected before the coating process is performed. Therefore, the same effects as in the first embodiment can be obtained, such as preventing the coating process from being performed while foreign matter F is attached to the nozzle guard NG.

[0099] Thus, in the tenth embodiment, the suction and travel control mechanism 552 corresponds to an example of the "nozzle moving section" of the present invention.

[0100] It should be noted that the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention. For example, in the tenth embodiment, the present invention is applied to a so-called levitation type substrate processing apparatus, but the foreign object detection unit 8 equipped in the second or third embodiment may also be applied. [Industrial applicability]

[0101] This invention is applicable to all substrate processing technologies in which a processing liquid is supplied to a substrate from a slit nozzle and applied to the substrate, with a nozzle guard positioned in front of the slit nozzle, which moves relative to the substrate. [Explanation of Symbols]

[0102] 1A, 1B... Coating equipment (substrate processing equipment) 2…Slit nozzle 3… Circuit board 7…Nozzle cleaning standby unit (reserve dispensing unit) 8...Foreign object detection unit 9…Nozzle cleaning unit (nozzle cleaning section) 10…Control Unit 11…Guard cleaning section (foreign object removal section) 12… Dry guard cleaner (foreign object removal section) 21…(Slit nozzle) discharge port 31… (The surface of the circuit board) 53…Nozzle movement section 552... Adsorption and travel control mechanism (nozzle movement section) D1… (Distance from the slit nozzle to the nozzle guard) D2… (Distance from the preliminary discharge section to the foreign object detection section) D3… (Distance from nozzle cleaning section to foreign object removal section) F...Foreign object NG... Nozzle guard

Claims

1. A substrate processing apparatus for applying a processing solution to the surface of a substrate, A slit nozzle having a slit-shaped discharge port for discharging the processing liquid, Above the substrate, a nozzle moving unit moves the slit nozzle, with its discharge opening facing downward, in a direction along the surface of the substrate, relative to the substrate; A plate-shaped nozzle guard is provided on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate by the nozzle moving part when the processing liquid is applied, and moves integrally with the slit nozzle. A foreign object detection unit for detecting foreign objects attached to the nozzle guard, When the foreign matter detection unit detects the foreign matter, the control unit restricts the application operation of the processing liquid to the substrate, A foreign matter removal unit for removing the foreign matter from the nozzle guard, The system includes a nozzle cleaning unit for cleaning the slit nozzle, The control unit controls the foreign matter removal unit so that the foreign matter is removed from the nozzle guard while the coating operation is restricted. The foreign matter removal unit is provided in the relative movement direction on the front side of the nozzle cleaning unit and at a distance from the nozzle cleaning unit equal to the distance from the slit nozzle to the nozzle guard. The control unit controls the nozzle cleaning unit and the foreign matter removal unit so that the cleaning of the slit nozzle by the nozzle cleaning unit and the removal of foreign matter by the foreign matter removal unit are performed at least partially in parallel. A substrate processing apparatus characterized by the following:

2. A substrate processing apparatus according to claim 1, The control unit is a substrate processing apparatus that, while restricting the coating operation, prompts the user to remove the foreign matter from the nozzle guard.

3. A substrate processing apparatus for applying a processing liquid to the surface of a substrate, A slit nozzle having a slit-shaped discharge port for discharging the processing liquid, Above the substrate, a nozzle moving unit moves the slit nozzle, with its discharge opening facing downward, in a direction along the surface of the substrate, relative to the substrate; A plate-shaped nozzle guard is provided on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate by the nozzle moving part when the processing liquid is applied, and moves integrally with the slit nozzle. A foreign object detection unit for detecting foreign objects attached to the nozzle guard, Before discharging the processing liquid from the outlet of the slit nozzle toward the surface of the substrate, a preliminary discharging unit waits at a preliminary discharging position away from the substrate, discharging a predetermined amount of the processing liquid from the outlet of the slit nozzle, A control unit that controls the pre-discharge unit and the foreign object detection unit, Equipped with, The foreign object detection unit is provided in the relative movement direction on the front side of the pre-discharge unit and at a distance from the pre-discharge unit equal to the distance from the slit nozzle to the nozzle guard. A substrate processing apparatus, wherein the control unit controls the pre-discharge unit and the foreign matter detection unit so that the discharge or standby of the processing liquid in the pre-discharge unit and the detection of the foreign matter in the foreign matter detection unit are performed at least partially in parallel.

4. A substrate processing apparatus for applying a processing liquid to the surface of a substrate, A slit nozzle having a slit-shaped discharge port for discharging the processing liquid, Above the substrate, a nozzle moving unit moves the slit nozzle, with its discharge opening facing downward, in a direction along the surface of the substrate, relative to the substrate; A plate-shaped nozzle guard is provided on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate by the nozzle moving part when the processing liquid is applied, and moves integrally with the slit nozzle. A foreign object detection unit for detecting foreign objects attached to the nozzle guard, Equipped with, The foreign object detection unit is a substrate processing apparatus that detects the foreign object based on the amount of light received by the light receiver while integrally moving along the tip of the nozzle guard a light receiver that emits a parallel light beam parallel to the relative direction of movement toward the tip of the nozzle guard and a light receiver that receives the parallel light beam that has come forward without being blocked by the nozzle guard.

5. A substrate processing apparatus for applying a processing liquid to the surface of a substrate, A slit nozzle having a slit-shaped discharge port for discharging the processing liquid, Above the substrate, a nozzle moving unit moves the slit nozzle, with its discharge opening facing downward, in a direction along the surface of the substrate, relative to the substrate; A plate-shaped nozzle guard is provided on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate by the nozzle moving part when the processing liquid is applied, and moves integrally with the slit nozzle. A foreign object detection unit for detecting foreign objects attached to the nozzle guard, Equipped with, The aforementioned foreign object detection unit detects the foreign object based on a projection image of the nozzle guard taken along the tip of the nozzle guard while emitting light from a direction parallel to the relative movement direction, in a substrate processing apparatus.

6. A substrate processing apparatus for applying a processing liquid to the surface of a substrate, A slit nozzle having a slit-shaped discharge port for discharging the processing liquid, Above the substrate, a nozzle moving unit moves the slit nozzle, with its discharge opening facing downward, in a direction along the surface of the substrate, relative to the substrate; A plate-shaped nozzle guard is provided on the front side of the slit nozzle in the relative movement direction in which the slit nozzle moves relative to the substrate by the nozzle moving part when the processing liquid is applied, and moves integrally with the slit nozzle. A foreign object detection unit for detecting foreign objects attached to the nozzle guard, Equipped with, The aforementioned foreign object detection unit detects the foreign object based on an image of the nozzle guard taken from below along the tip of the nozzle guard, in a substrate processing apparatus.

7. A coating step in which the processing liquid is applied to the surface of the substrate by moving the slit nozzle and a plate-shaped nozzle guard relative to the substrate while discharging the processing liquid from the discharge port of the slit nozzle with the discharge port close to the surface of the substrate, thereby preventing foreign matter from adhering to the slit nozzle with the nozzle guard, which is provided on the front side of the slit nozzle in the relative movement direction of the slit nozzle, Prior to the coating process, a detection step is performed to detect the adhesion of foreign matter to the nozzle guard, When the foreign matter is detected by the foreign matter detection unit, the process of applying the processing liquid to the substrate is restricted. With the aforementioned coating operation restricted, the foreign matter is removed from the nozzle guard by the foreign matter removal unit, The process includes a step of cleaning the slit nozzle with a nozzle cleaning unit, The foreign matter removal unit is provided in the relative movement direction on the front side of the nozzle cleaning unit and at a distance from the nozzle cleaning unit equal to the distance from the slit nozzle to the nozzle guard. The cleaning of the slit nozzle by the nozzle cleaning unit and the removal of the foreign matter by the foreign matter removal unit are performed at least partially in parallel. A substrate processing method characterized by the following:

8. A coating step in which the slit nozzle and a plate-shaped nozzle guard are moved relative to the substrate while the discharge port of the slit nozzle is brought close to the surface of the substrate and the processing liquid is discharged from the discharge port, thereby applying the processing liquid to the surface of the substrate while preventing foreign matter from adhering to the slit nozzle by the nozzle guard, which is provided on the front side of the slit nozzle in the relative movement direction of the slit nozzle, Prior to the coating process, a detection step is performed in which a foreign matter detection unit detects the adhesion of foreign matter to the nozzle guard, The process includes a step of discharging a predetermined amount of the processing liquid from the discharge port of the slit nozzle at a preliminary discharge position away from the substrate by a preliminary discharge unit before discharging the processing liquid from the discharge port of the slit nozzle toward the surface of the substrate, and waiting there. The foreign object detection unit is provided in the relative movement direction on the front side of the pre-discharge unit and at a distance from the pre-discharge unit equal to the distance from the slit nozzle to the nozzle guard. The discharge or standby of the processing liquid by the pre-discharge unit and the detection of the foreign matter by the foreign matter detection unit are performed at least partially in parallel. A substrate processing method characterized by the following:

9. A coating step in which the slit nozzle and a plate-shaped nozzle guard are moved relative to the substrate while the discharge port of the slit nozzle is brought close to the surface of the substrate and the processing liquid is discharged from the discharge port, thereby applying the processing liquid to the surface of the substrate while preventing foreign matter from adhering to the slit nozzle by the nozzle guard, which is provided on the front side of the slit nozzle in the relative direction of movement of the slit nozzle, Prior to the coating process, a detection step is performed in which a foreign matter detection unit detects the adhesion of foreign matter to the nozzle guard, Equipped with, The foreign object detection unit integrates a light emitter that projects a parallel light beam parallel to the relative movement direction toward the tip of the nozzle guard, and a light receiver that receives and receives the parallel light beam that has come forward without being blocked by the nozzle guard, and detects the foreign object based on the amount of light received by the light receiver while moving these together along the tip of the nozzle guard. A substrate processing method characterized by the following:

10. A coating step in which the slit nozzle and a plate-shaped nozzle guard are moved relative to the substrate while the discharge port of the slit nozzle is brought close to the surface of the substrate and the processing liquid is discharged from the discharge port, thereby applying the processing liquid to the surface of the substrate while preventing foreign matter from adhering to the slit nozzle by the nozzle guard, which is provided on the front side of the slit nozzle in the relative movement direction of the slit nozzle, Prior to the coating process, a detection step is performed in which a foreign matter detection unit detects the adhesion of foreign matter to the nozzle guard, Equipped with, The foreign object detection unit detects the foreign object based on a projection image of the slit nozzle, which is captured along the tip of the slit nozzle while emitting light from a direction parallel to the relative movement direction. A substrate processing method characterized by the following:

11. A coating step in which the slit nozzle and a plate-shaped nozzle guard are moved relative to the substrate while the discharge port of the slit nozzle is brought close to the surface of the substrate and the processing liquid is discharged from the discharge port, thereby applying the processing liquid to the surface of the substrate while preventing foreign matter from adhering to the slit nozzle by the nozzle guard, which is provided on the front side of the slit nozzle in the relative direction of movement of the slit nozzle, Prior to the coating process, a detection step is performed in which a foreign matter detection unit detects the adhesion of foreign matter to the nozzle guard, Equipped with, The foreign object detection unit detects the foreign object based on an image of the slit nozzle taken from below along the tip of the slit nozzle. A substrate processing method characterized by the following:

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