JP3853685B2 - Substrate processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique in a substrate processing apparatus for applying a processing liquid to a rectangular substrate by a slit nozzle.
[0002]
[Prior art]
A substrate processing apparatus for applying a processing liquid such as a photoresist to the surface of a square substrate (glass square substrate for liquid crystal, flexible substrate for film liquid crystal, substrate for photomask, substrate for color filter, etc.) has a slit-like discharge part A technique (slit coating) in which a processing liquid is applied using a slit nozzle is known. In the slit coating, the processing liquid is applied onto the substrate while the slit nozzle moves with respect to the horizontally held substrate.
[0003]
In such a substrate processing apparatus, there may be a case where a coating defect due to streak-like shading as shown in FIG. 8 occurs. This often occurs because the treatment liquid at the tip of the nozzle dries while the slit nozzle is waiting, and the treatment liquid is not normally ejected from the nozzle when the ejection of the treatment liquid is started. Conventionally, such a coating defect has been detected by providing an inspection process for inspecting the substrate after a series of processes in the substrate processing apparatus is completed.
[0004]
[Problems to be solved by the invention]
However, when detecting a coating failure on a substrate in the inspection process after the processing is completed, there is a time lag between the occurrence of the coating failure and the detection of the coating failure. There was a problem that there was a high possibility of being wasted due to a defect.
[0005]
In addition, there is a problem in that useless processing is performed because a substrate with poor coating is also transferred to post-processing performed before the inspection process.
[0006]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a substrate processing apparatus that can detect application failure early and reduce waste caused by application failure.
[0007]
[Means for Solving the Problems]
  In order to solve the above problems, the invention of claim 1 is directed to a coating unit that applies a processing liquid to the surface of the substrate while scanning a square substrate in a predetermined direction, and a substrate on which the processing liquid is applied by the coating unit. A substrate processing apparatus comprising: a transport unit that transports the liquid from the coating unit and transports it to the next process along a predetermined transport path;The coating unit includes a slit nozzle that discharges a processing liquid,An imaging unit that is provided in any of the sections from the coating unit to the delivery position of the substrate to the next process, and that captures a surface image of the substrate coated with the processing liquid, and an imaging output of the imaging unit Based on the treatment liquid on the substrateWith regard to the presence or absence of streaky application failure along the predetermined directionAnd determining means for determiningThe imaging range of the imaging means is a part of the surface of the substrate, while the imaging range covers the entire range of the substrate in a direction orthogonal to the predetermined direction..
[0008]
Further, the invention of claim 2 is the substrate processing apparatus according to the invention of claim 1, further comprising a buffer for temporarily storing the substrate being processed, and according to the determination result of the determination means, The substrate being processed is stored in the buffer.
[0009]
According to a third aspect of the present invention, in the substrate processing apparatus according to the second aspect of the present invention, a plurality of the buffers are provided, and the processing is being performed from among the plurality of buffers according to the processing status of the substrate being processed. Select a buffer to store the board.
[0011]
  Also,Claim 4The invention of claim 1 to claim 13In the substrate processing apparatus according to any one of the above, the imaging range includes a start end of scanning application of the processing liquid in the application unit.
[0012]
  Also,Claim 5The invention of claim 1 to claim 14In the substrate processing apparatus according to any one of the inventions, the imaging range includes the vicinity of the end of the substrate.
[0013]
  Also,Claim 6The invention of claim5In the substrate processing apparatus according to the invention, the imaging range includes a central portion side of the substrate in addition to the vicinity of the end portion.
[0014]
  Also,Claim 7The invention of claim 1 to claim 16In the substrate processing apparatus according to any one of the above, the imaging means is disposed above the holding position of the substrate in the coating unit.
[0015]
  The invention according to claim 8 is a holding base that holds a square substrate, a slit nozzle that extends in a substantially horizontal direction, and is bridged substantially horizontally above the holding base, and the bridge Moving means for moving the structure in a substantially horizontal direction along the surface of the substrate, and the bridging structure along the surface of the substrate.In a given directionIn the substrate processing apparatus for forming a layer of the processing liquid on the surface by discharging a predetermined processing liquid from the slit nozzle to the surface of the substrate while being moved, the substrate is provided above the holding table. An image pickup means for picking up the upper surface image; and a determination means for determining the presence or absence of a streaky application defect along the predetermined direction with respect to the treatment liquid based on the image pickup output of the image pickup means, The imaging range of the imaging means is a part of the surface of the substrate, while the imaging range covers the entire range of the substrate in the direction orthogonal to the predetermined direction.
[0017]
  Also,Claim 9The invention of claim8In the substrate processing apparatus according to the invention, the imaging range includes a start end of scanning application of the processing liquid in the application unit.
[0018]
  Also,Claim 10The invention of claim8 or 9In the substrate processing apparatus according to the invention, the imaging range includes the vicinity of the end of the substrate.
[0019]
  Further, the invention of claim 11 is a claim.10In the substrate processing apparatus according to the invention, the imaging range includes a central portion side of the substrate in addition to the vicinity of the end portion.
[0020]
  The invention of claim 12 is the substrate processing apparatus according to any one of claims 1 to 11, wherein the slit nozzle is cleaned when the streak-like coating failure is detected by the determination means. A mechanism is further provided.
  Further, in the substrate processing apparatus according to any one of the first to twelfth aspects, the processing liquid applied to the surface of the substrate is not exposed to light when the imaging unit performs imaging. Further, an illumination means for illuminating the surface of the substrate is further provided.
  According to a fourteenth aspect of the present invention, in the substrate processing apparatus according to any one of the first to thirteenth aspects, the substrate is a substrate for a flat panel display, and the processing solution is a resist solution.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.
[0022]
  <1.FirstEmbodiment>
  FIG. 1 is a conceptual plan view showing a configuration of a substrate processing apparatus 1 in the present embodiment. The substrate processing apparatus 1 is provided as a part of the substrate processing system SYS, and includes a control unit 2 that controls each component in the apparatus, a loader 10 that takes a substrate to be processed into the apparatus, a cleaning machine 11, and a substrate in a predetermined manner. Transport robots 12 and 13 that transport along the transport path, a heat treatment unit HP that performs heat treatment on the substrate, a cooling unit CP that cools the substrate, buffers BF1 to BF4 that temporarily store the substrate being processed, and a surface of the substrate Coating unit 14 for applying a resist, drying unit 15 for pre-drying resist (for example, air drying, vacuum drying, etc.), titler 16 for placing a title such as a control number on a substrate, developing machine 19, post for performing heat treatment A bake device 20 and an unloader 21 for carrying the processed substrate out of the device are provided.
[0023]
The substrate processing apparatus 1 is adjacent to an exposure apparatus (stepper) 17 that forms a circuit pattern or the like on a substrate by selective exposure. The substrate on which the resist coating, which will be described later, has been completed is applied to the stepper 17, and the substrate after the exposure by this stepper 17 is conveyed by the conveyor 18 so that it returns to the substrate processing apparatus 1 and undergoes development processing. It has become. Although not shown, the control unit 2 is connected to each component in the substrate processing apparatus 1 so that signals can be transmitted and received.
[0024]
In the substrate processing apparatus 1, first, the loader 10 takes in the substrate to be processed and cleans the substrate with the cleaning machine 11, thereby removing dirt attached to the substrate surface. Next, the transfer robot 12 transfers the substrate to the heat treatment unit HP. In the heat treatment unit HP, the cleaning liquid is evaporated and dried by heating the substrate. Subsequently, the heated substrate is transported to the cooling unit CP and cooled to a predetermined temperature. Thus, the pre-application process for applying the resist is completed.
[0025]
The substrate for which the pre-process has been completed is transported to the coating unit 14 by the transport robot 12 and applied with a resist.
[0026]
FIG. 2 is a perspective view showing a configuration of the coating unit 14 according to the embodiment of the present invention. FIG. 3 is a plan view of the coating unit 14 as viewed from above. 4 and 5 are a front view and a side view of the coating unit 14, respectively.
[0027]
The coating unit 14 includes a stage 3 that functions as a holding table for placing and holding the substrate to be processed 90 and also functions as a base for each attached mechanism. The stage 3 is made of an integral stone having a rectangular parallelepiped shape, and its upper surface (holding surface 30) and side surfaces are processed into flat surfaces.
[0028]
The upper surface of the stage 3 is a horizontal plane and serves as a holding surface 30 for the substrate 90. A number of vacuum suction ports are distributed and formed on the holding surface 30, and the substrate 90 is held at a predetermined horizontal position by sucking the substrate 90 while the substrate processing apparatus 1 processes the substrate 90.
[0029]
A pair of running rails 31a extending in parallel in a substantially horizontal direction are fixed to both ends of the holding surface 30 across the placement area of the substrate 90 (region where the substrate 90 is placed). The traveling rail 31a guides the movement of the bridging structure 4 together with the support blocks 31b fixed to both ends of the bridging structure 4 (the moving direction is defined in a predetermined direction), and the bridging structure 4 is positioned above the holding surface 30. To support.
[0030]
Above the stage 3, a bridging structure 4 is provided that extends substantially horizontally from both sides of the stage 3. The bridging structure 4 is mainly composed of a nozzle support portion 40 that uses carbon fiber resin as an aggregate, and lifting mechanisms 43 and 44 that support both ends thereof.
[0031]
A slit nozzle 41 and a gap sensor 42 are attached to the nozzle support portion 40.
[0032]
The slit nozzle 41 extending in the horizontal Y direction is connected to a discharge mechanism (not shown) including a pipe for supplying a chemical solution to the slit nozzle 41 and a resist pump. The slit nozzle 41 is supplied with a resist by a resist pump and scans the surface of the substrate 90, thereby discharging the resist to a predetermined region on the surface of the substrate 90 (hereinafter referred to as “resist application region”).
[0033]
The gap sensor 42 is attached to the nozzle support portion 40 so as to be in the vicinity of the slit nozzle 41, and the height difference (gap) between the lower presence object (for example, the surface of the substrate 90 or the surface of the resist film) is determined. taking measurement. Specifically, the gap sensor 42 includes a light source that irradiates laser light downward (toward the substrate) and a light receiving element that receives reflected light from below, and a distance from the reflected light to an object existing below. Is detected.
[0034]
As described above, the slit nozzle 41 and the gap sensor 42 are attached to the nozzle support portion 40, so that their relative positional relationship is fixed. Therefore, the substrate processing apparatus 1 can detect the distance between the surface of the substrate 90 and the slit nozzle 41 based on the measurement result of the gap sensor 42. The substrate processing apparatus 1 according to the present embodiment includes two gap sensors 42. However, the number of gap sensors 42 is not limited to this, and more gap sensors 42 may be provided. . Although not shown, the coating unit 14 includes a cleaning mechanism including a cleaning nozzle that discharges a solvent for cleaning the slit nozzle 41, and the cleaning nozzle cleans the slit nozzle 41 as necessary. .
[0035]
The elevating mechanisms 43 and 44 are divided on both sides of the slit nozzle 41 and connected to the slit nozzle 41 by the nozzle support portion 40. The elevating mechanisms 43 and 44 are used for moving the slit nozzle 41 in translation and adjusting the posture of the slit nozzle 41 in the YZ plane.
[0036]
A pair of AC coreless linear motors (hereinafter simply referred to as “linear motors”) 50 arranged separately on both sides of the stage 3 are respectively fixed to both ends of the bridging structure 4.
[0037]
Each of the pair of linear motors 50 includes a stator (stator) 50a and a mover 50b, and a driving force for moving the bridging structure 4 in the X-axis direction by electromagnetic interaction between the stator 50a and the mover 50b. Is a motor that generates Further, the moving amount and moving direction of each linear motor 50 can be controlled by a control signal from the control unit 2.
[0038]
The pair of linear encoders 52 arranged on the left and right of the stage 3 includes a scale unit and a detector (not shown), detects the relative positional relationship between the scale unit and the detector, and transfers the detected relative positional relationship to the control unit 2. The scale portion is fixed to the stage 3, and the detector is fixed to the vicinity of each linear motor 50 fixed to the bridging structure 4. Therefore, the control unit 2 can detect the position of each linear motor 50 based on the detection result from each linear encoder 52, and can control the position of each linear motor 50 based on the detection result.
[0039]
Furthermore, the coating unit 14 includes an image recognition unit 22 including an imaging unit 23 and a determination unit 24.
[0040]
The imaging unit (two-dimensional CCD camera) 23 is attached above the stage 3 and captures a two-dimensional image of the surface of the substrate 90 after the treatment liquid is applied. In addition, the imaging unit 23 transfers the captured image data to the determination unit 24.
[0041]
The determination unit 24 is provided inside the stage 3, and determines the application state of the resist formed on the substrate 90 by performing image recognition processing on the image data (image output) transferred from the image pickup unit 23. To do. Further, the determination result is transferred to the control unit 2 of the substrate processing apparatus 1.
[0042]
The coating unit 14 starts the resist coating process when the transport robot 12 transports the substrate 90 after the pre-coating process.
[0043]
First, the stage 3 sucks and holds the substrate 90 at a predetermined position on the holding surface 30. Subsequently, the elevating mechanisms 43 and 44 move the gap sensor 42 attached to the nozzle support unit 40 to a predetermined altitude (hereinafter referred to as “measurement altitude”). At this time, the control unit 2 gives a control signal to each of the lifting mechanisms 43 and 44 based on the detection result of each rotary encoder 442 provided in each of the lifting mechanisms 43 and 44, thereby Control the position.
[0044]
When the gap sensor 42 is set at the measurement altitude, the linear motor 50 moves the bridging structure 4 in the X direction to move the gap sensor 42 to above the resist application region. At this time, the control unit 2 controls the position of the gap sensor 42 by giving a control signal to each linear motor 50 based on the detection result of the linear encoder 52.
[0045]
Next, the gap sensor 42 starts measuring the gap from the resist application region. When the measurement is started, the linear motor 50 moves the bridging structure 4 so that the gap sensor 42 scans the resist coating region, and the measurement result during the scanning is transferred to the control unit 2.
[0046]
When the scanning by the gap sensor 42 is completed, the control unit 2 determines that the posture of the slit nozzle 41 in the YZ plane is an appropriate posture (the interval between the slit nozzle 41 and the resist coating region is based on the measurement result from the gap sensor 42. The position of the nozzle support portion 40 that becomes an appropriate interval for applying the resist (hereinafter referred to as “appropriate attitude”) is calculated, and the elevator mechanisms 43 and 44 are controlled based on the calculation result. Give a signal. Based on the control signal, the respective lifting mechanisms 43 and 44 move the nozzle support portion 40 in the Z-axis direction to adjust the slit nozzle 41 to an appropriate posture. Further, the linear motor 50 moves the bridging structure 4 and moves the slit nozzle 41 to the discharge start position.
[0047]
When the slit nozzle 41 moves to the discharge start position, the control unit 2 gives a control signal to the linear motor 50 and a resist pump (not shown). Based on the control signal, the linear motor 50 moves the bridging structure 4 in the −X direction so that the slit nozzle 41 scans the surface of the substrate 90, and the resist pump is operated during the scanning of the slit nozzle 41. Thus, the resist is sent to the slit nozzle 41, and the slit nozzle 41 discharges the resist to the resist application region. As a result, a resist layer is formed on the surface of the substrate 90.
[0048]
When the slit nozzle 41 moves to the discharge end position, the control unit 2 gives a control signal to the linear motor 50 and the resist pump. Based on the control signal, when the resist pump is stopped, the discharge of the resist from the slit nozzle 41 is stopped, and the linear motor 50 moves the bridging structure 4 to the initial position.
[0049]
When the resist coating process is completed, the imaging unit 23 captures an image of the surface of the substrate 90 coated with the resist, and transfers the image to the determination unit 24. FIG. 6 is a diagram illustrating an imaging range 230 of the imaging unit 23 with respect to the substrate 90. As shown in FIG. 6, the imaging range 230 is set so as to include the end region of the substrate 90 and the end region of the resist coating region 231 (near the position where the resist coating is started).
[0050]
This is because, as described above, the defective coating due to the blur as shown in FIG. 8 mainly occurs at the start of resist coating as described above, and therefore occurs near the edge of the substrate or near the position where the resist coating is started. This is because such application defects can be efficiently detected by selectively imaging and inspecting those areas.
[0051]
Thus, the imaging range 230 is a part of the surface of the substrate 90 in the scanning direction (X-axis direction) of the slit nozzle 41, while the substrate is in a direction (Y-axis direction) orthogonal to the scanning direction of the slit nozzle 41. By covering the entire range of the 90 surfaces, the amount of image data can be reduced compared to the case of capturing an image of the entire surface of the substrate, so that the image recognition processing can be speeded up. In addition, the resolution of the imaging unit 23 can be improved.
[0052]
When imaging by the imaging unit 23 is completed, the determination unit 24 performs image recognition processing on the image data, determines the application state of the resist solution on the substrate 90, and transfers the determination result to the control unit 2. Such image processing and determination processing use, for example, that a resist coating portion is relatively dark and a coating defect portion such as a coating shading portion is relatively bright. This can be done by binarizing and determining the extent of the bright part in the image using the pixel number threshold.
[0053]
In this way, by separately determining the application state of the resist solution on the substrate 90 according to the image data of the imaging unit 23 provided in the application unit 14, a series of processing in the substrate processing apparatus 1 is completed separately. Compared with the case where an inspection process is provided, the application failure of the substrate 90 can be detected at an early stage.
[0054]
As a result of the determination by the determination unit 24, if no application failure of the substrate 90 is detected (inspection result is normal), the substrate processing apparatus 1 performs a predetermined process on the substrate 90 as follows.
[0055]
First, the stage 3 stops the adsorption of the substrate 90. Subsequently, the transfer robot 12 picks up the substrate 90 from the holding surface 30, unloads it from the coating unit 14, and transfers it to the drying unit 15. The drying unit 15 performs preliminary drying of the resist applied to the substrate 90 by, for example, drying under reduced pressure.
[0056]
Next, the heat treatment unit HP pre-bakes the substrate 90, and the cooling unit CP cools the pre-baked substrate 90 to a predetermined temperature. Note that pre-baking is a heat treatment performed after applying a resist on a substrate to evaporate residual solvent in the coating film and enhance adhesion between the coating film and the substrate. Further, the transfer of the substrate 90 during this time is also performed by the transfer robot 12.
[0057]
The substrate 90 that has been cooled after pre-baking in the cooling unit CP is transported to the titler 16 by the transport robot 13, assigned a management number, and then transported to the stepper 17 for exposure processing. Further, while being conveyed by the conveyor 18, the developing process by the developing machine 19 and the post-baking process by the post-baking apparatus 20 are performed, and the unloader 21 carries out the apparatus.
[0058]
On the other hand, when the application failure of the substrate 90 is detected by the determination unit 24 (inspection result is abnormal), the substrate processing apparatus 1 performs processing on the substrate 90 as follows. Hereinafter, the substrate 90 in which the application failure is detected is referred to as a “defective substrate 91”.
[0059]
First, similarly to the normal substrate 90, processing up to the cooling processing after pre-baking is performed on the defective substrate 91.
[0060]
The defective substrate 91 for which the cooling process after pre-baking has been completed is transferred to the buffer BF1 or BF2 by the transfer robot 13.
[0061]
As described above, the defective substrate 91 is not transferred to a subsequent process such as an exposure process, but is stored in the buffer and separated, so that a wasteful process can be reduced for a substrate that needs to be reprocessed.
[0062]
Further, the control unit 2 controls the coating unit 14 so as to clean the slit nozzle 41 of the coating unit 14. First, the elevating mechanisms 43 and 44 and the linear motor 50 are controlled to move the slit nozzle 41 to a cleaning position corresponding to the cleaning mechanism. Next, the slit nozzle 41 is cleaned by scanning the nozzle tip of the slit nozzle 41 while the cleaning nozzle discharges the medicine.
[0063]
As described above, when a coating failure is detected, the substrate processing apparatus 1 is in a state in which the coating failure occurs by automatically performing a cleaning process on the slit nozzle 41 which is the main cause of the coating failure. Can be recovered efficiently. Note that the method of cleaning the slit nozzle 41 is not limited to the above-described method, and other configurations and methods may be used.
[0064]
Further, the control unit 2 controls the transport robot 12 to transport the buffer unit BF3 or BF4 until the coating unit 14 completes the cleaning process of the slit nozzle 41.
[0065]
When the cleaning process of the slit nozzle 41 is completed, the transport robot 12 transports the substrate 90 stored in the buffers BF3 and BF4 to the coating unit 14, and the coating unit 14 resumes the resist coating process. Further, the defective substrate 91 transported to the buffers BF1 and BF2 is transported to the resist stripping process, and is reused after stripping incompletely applied resist.
[0066]
In this way, by interrupting the conveyance of the substrate to the coating unit 14 in a state where the coating failure has occurred, it is possible to further reduce the generation of the substrate that causes the coating failure, thereby reducing wasteful processing. be able to. In addition, when a coating failure is detected, the processing status of each stored substrate can be identified by storing the substrates in different buffers depending on whether or not the coating processing has been completed. The processing can be appropriately started for each of the formed substrates.
[0067]
After the resist coating process is resumed, the substrate processing apparatus 1 performs a predetermined process as in the case where the inspection result is normal.
[0068]
As described above, the substrate processing apparatus 1 provides the image recognition unit 22 in the coating unit 14 and inspects the application failure, so that the application failure is detected earlier than the case where a separate inspection process is provided at the end of the series of processes. Can be detected.
[0069]
Moreover, since the substrate processing apparatus 1 can prevent a defective substrate from being transported to a subsequent process by storing a substrate in which a coating defect has occurred in a buffer, wasteful processing can be reduced.
[0070]
Further, by selecting a buffer for storing each substrate based on the processing state of the substrate at the time when a coating defect is detected, the processing can be appropriately restarted for the stored substrate. In addition, when a coating defect is detected again after restarting the process, the operator may be notified by an alarm. In that case, the worker stops the loading of the substrate from the loader 10 and performs the nozzle replacement operation. Further, an automatic nozzle replacement function may be provided.
[0071]
Moreover, since the substrate processing apparatus 1 can reduce the data amount of the image data on the substrate surface by appropriately setting the imaging range of the imaging unit 23, the substrate processing apparatus 1 can perform an efficient inspection.
[0072]
In this embodiment, in order for the imaging unit 23 to capture an image, the substrate surface needs to be illuminated to such an extent that it can be imaged. However, when the coating liquid is a photosensitive material, this illumination is The photosensitive material must be strong enough not to be exposed to light or have a wavelength that is not exposed to light, and illumination is performed within that range.
[0073]
<2. Second Embodiment>
In the first embodiment, the imaging range of the imaging unit 23 is set as a range including the edge region of the substrate and the edge region of the resist coating region. If this occurs due to “insufficient” or “nozzle clogging”, it may be considered that the area of the central portion of the substrate is blurred. Therefore, the imaging range of the imaging unit 23 may be set so as to further include the central portion of the substrate.
[0074]
FIG. 7 is a diagram showing an imaging range 232 in the imaging unit 23 of the substrate processing apparatus 1 according to the second embodiment configured according to such a principle. The imaging range 232 includes an area of the central portion of the substrate 90 in addition to the imaging range 230 shown in FIG.
[0075]
The imaging unit 23 of the substrate processing apparatus 1 in the present embodiment images the image data in the imaging range 232 and transfers it to the determination unit 24. The determination unit 24 performs image recognition processing on the image data in the same manner as in the first embodiment, and determines whether there is a coating defect.
[0076]
As described above, the substrate processing apparatus 1 according to the second embodiment can obtain the same effects as those of the first embodiment, and can also detect application defects in which a blur is generated near the central portion of the substrate. And an accurate inspection can be performed. Note that, when imaging a plurality of partial regions in the surface of the substrate 90 as in the imaging unit 23 of the present embodiment, the imaging unit 23 is moved relative to the substrate 90 to capture the image. May be.
[0077]
<3. Third Embodiment>
FIG. 9 is a diagram showing a third embodiment of the present invention. In this embodiment, the gap sensor 42 attached and fixed to the nozzle support 40 in the first embodiment is orthogonal to the longitudinal direction of the nozzle support 40, that is, the moving direction (scanning direction) of the nozzle support 40. And a drive mechanism (not shown) for moving the gap sensor 42 is provided.
[0078]
The gap sensor 42 measures a gap with a lower entity. In the first embodiment, the gap sensor 42 is a slit nozzle 41 (not shown in FIG. 9) attached to the nozzle support 40 before the coating operation. ) And the resist coating area of the substrate 90 is measured, and the elevating mechanisms 43 and 44 (not shown in FIG. 9) are controlled to apply the coating so that the distance is appropriate. In the third embodiment, the same operation as that of the first embodiment is performed, and further, during coating, that is, the nozzle support portion 40 moves in the −X direction, and the coating liquid is discharged from the slit nozzle 41. During the discharge, the gap sensor 42 located on the rear side in the movement direction as viewed from the nozzle support portion 40 reciprocates in the Y direction and the −Y direction as indicated by an arrow A in the figure, and the measurement operation is performed. Do. That is, while the nozzle support unit 40 moves in the −X direction in FIG. 9 and performs application, measurement is performed on the entire width of the substrate 90 in a direction orthogonal to the scanning direction of the nozzle support unit 40.
[0079]
As a result, the measurement result is the distance to the upper surface of the coating film when the coating liquid on the surface of the substrate 90 is applied, and if there is an area where the coating liquid is not applied, it is the distance to the upper surface of the substrate measured earlier. It becomes an interval. Therefore, if the measurement result and the positional information in the X direction of the gap sensor 42 at the time of measurement are combined, an image representing the distribution of the coating film on the surface of the substrate 90 (a pseudo image created from a numerical value indicating an interval, hereinafter In the same way as in the above-described embodiment, the determination unit 24 performs image recognition processing on the pseudo image, and determines the presence / absence of an uncoated portion.
[0080]
Also in this case, if there is an unapplied portion B that is not coated due to clogging or the like in the width direction of the slit nozzle 41, the unapplied portion B is moved along the movement path of the gap sensor 42 as shown in FIG. The determination unit 24 can reliably detect the presence of the uncoated portion B. Further, in this embodiment, the gap sensor 42 for detecting the gap between the substrate 90 and the slit nozzle 41 is also used for capturing a surface image representing the uncoated portion B (acquisition of a pseudo image). It is not necessary to provide (for example, the imaging unit 23 in the above embodiment).
[0081]
In addition, like the gap sensor 42 in this Embodiment, you may provide separately the imaging means only for imaging of the surface image showing the uncoated part B, moving along the slit nozzle 41. FIG. Also in this embodiment, the light source for irradiating the laser beam of the gap sensor 42 is strong enough to prevent the photosensitive material from being exposed when the coating liquid is a photosensitive material. Or a non-photosensitive wavelength, in which range a light source is used.
[0082]
<4. Modification>
Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made.
[0083]
For example, the place where the image recognition unit 22 is provided is not limited to the coating unit 14. For example, the image recognition unit 22 is independently provided at a predetermined position above the substrate 90 transfer path in the substrate processing apparatus 1, and the transfer robot 12 transfers the resist-coated substrate 90 to a position below the image recognition unit 22. You may make it do. Alternatively, the transfer robot 12 may be temporarily stopped when taking out the substrate 90 from the coating unit 14, and during that time, imaging may be performed for inspection. That is, the image recognition unit 22 may be provided anywhere as long as it is a section from the coating unit 14 to the delivery position of the substrate 90 to the next process (the drying unit 15 in the example of FIG. 1).
[0084]
Further, the imaging unit 23 and the determination unit 24 of the image recognition unit 22 are not necessarily provided in the same place. For example, the imaging unit 23 may be provided in the coating unit 14 and the determination unit 24 may be provided in the control unit 2.
[0085]
In the above embodiment, the imaging range of the imaging unit 23 is not limited to the entire surface of the substrate, but to a highly probable range where blurring occurs. However, the imaging range of the imaging unit 23 is the entire surface of the substrate. The determination unit 24 may selectively perform the image recognition process only on a highly probable range where blur is generated in the range captured by the image data.
[0086]
In the above-described embodiment, the substrate processing apparatus 1 has been described as a device that performs a series of processing (not only coating processing but also development processing) on the substrate. However, the present invention is not limited to this, and only coating processing is performed. The same can be applied to an independent substrate processing apparatus. In that case, since the inspection can be performed in the substrate processing apparatus, it is not necessary to provide a separate inspection process for the substrate that has been processed in the substrate processing apparatus.
[0087]
【The invention's effect】
  Claim 1 to7In the invention described in the above, based on the imaging output of the imaging means that is provided in any of the sections from the coating unit to the delivery position of the substrate to the next process and that images the surface image of the substrate coated with the processing liquid, By determining the application state of the treatment liquid on the substrate, it is possible to detect an application defect on the substrate at an early stage as compared with a case where a separate inspection process is provided after a series of processes is completed.
[0088]
According to the second aspect of the present invention, since the substrate being processed is stored in the buffer based on the determination result of the determination unit, the processing on the substrate can be interrupted when a coating defect is detected. Processing can be reduced.
[0089]
According to the third aspect of the present invention, the processing status of each stored substrate is identified by selecting a buffer for storing the substrate being processed from a plurality of buffers according to the processing status of the substrate being processed. can do.
[0090]
  Claim1and8In the invention described in (1), the imaging range by the imaging means is a part of the surface of the substrate, while the imaging range covers the entire range of the substrate in the direction orthogonal to the predetermined direction.AndThus, an efficient inspection can be performed.
[0091]
  Claim4and9In the invention described in (4), since the imaging range includes the start end of the scanning application of the treatment liquid in the application unit, it is possible to image a position where blurring is likely to occur, so that an efficient inspection can be performed.
[0092]
  Claim5and10In the invention described in (1), since the imaging range includes the vicinity of the edge of the substrate, it is possible to image a position where blurring is likely to occur, so that an efficient inspection can be performed.
[0093]
  Claim6and11In the invention described in the above, the imaging range includes not only the vicinity of the end portion but also the central portion side of the substrate, thereby detecting a coating defect even when the blur occurs only on the central portion side of the substrate. Therefore, the detection accuracy can be improved.
[0094]
  Claim7In the invention described in (1), the imaging means can be detected at an early stage by being arranged above the holding position of the substrate in the coating unit.
[0095]
  Claim8In the invention described in the thirteenth to fourteenth aspects, it is not necessary to provide a separate inspection step by determining the application state of the treatment liquid based on the imaging output of the imaging means.
[Brief description of the drawings]
FIG. 1 is a schematic plan view showing a configuration of a substrate processing apparatus according to a first embodiment.
FIG. 2 is a perspective view showing a coating unit.
FIG. 3 is a plan view of a coating unit.
FIG. 4 is a front view of a coating unit.
FIG. 5 is a side view of the coating unit.
FIG. 6 is a diagram illustrating an imaging range of an imaging unit in the first embodiment.
FIG. 7 is a diagram illustrating an imaging range of an imaging unit in the second embodiment.
FIG. 8 is a view showing a substrate on which a coating defect has occurred due to streaks.
FIG. 9 is a schematic perspective view illustrating a configuration of a substrate processing apparatus according to a third embodiment.
[Explanation of symbols]
1 Substrate processing equipment
10 Loader
11 Washing machine
12, 13 Transport robot
14 Application unit
2 Control unit
22 Image recognition unit
23 Imaging unit
230,232 Imaging range
24 judgment part
3 stages
4 Cross-linked structure
41 Slit nozzle
42 Gap sensor
50 AC coreless linear motor
90 substrates
91 Bad substrate
BF1, BF2, BF3, BF4 buffer

Claims (14)

An application unit that applies a treatment liquid to the surface of the substrate while scanning a square substrate in a predetermined direction;
A transport unit that unloads the substrate coated with the processing liquid by the coating unit from the coating unit and transports the substrate to the next step along a predetermined transport path;
In a substrate processing apparatus comprising:
The coating unit includes a slit nozzle that discharges a processing liquid,
An imaging unit that is provided in any of the sections from the coating unit to the delivery position of the substrate to the next process, and that captures a surface image of the substrate coated with the treatment liquid;
Determination means for determining the presence or absence of streak-like application defects along the predetermined direction with respect to the processing liquid on the substrate based on an imaging output of the imaging means;
Further comprising
The image pickup range of the image pickup means is a part of the surface of the substrate, while the image pickup range covers the entire range of the substrate in a direction orthogonal to the predetermined direction. apparatus. The substrate processing apparatus according to claim 1,
A buffer for temporarily storing the substrate being processed;
The substrate processing apparatus, wherein the substrate being processed is stored in the buffer according to a determination result of the determination means. The substrate processing apparatus according to claim 2,
Comprising a plurality of said buffers;
A substrate processing apparatus, wherein a buffer for storing the substrate being processed is selected from the plurality of buffers according to a processing state of the substrate being processed. The substrate processing apparatus according to any one of claims 1 to 3,
The substrate processing apparatus, wherein the imaging range includes a start end of scanning application of the processing liquid in the application unit. The substrate processing apparatus according to claim 1,
The substrate processing apparatus, wherein the imaging range includes a vicinity of an end of the substrate. The substrate processing apparatus according to claim 5,
The substrate processing apparatus, wherein the imaging range includes a central portion side of the substrate in addition to the vicinity of the end portion. The substrate processing apparatus according to claim 1,
The substrate processing apparatus, wherein the imaging unit is disposed above the holding position of the substrate in the coating unit. A holding base for holding a square substrate;
Holding a slit nozzle extending in a substantially horizontal direction, and a bridging structure that extends substantially horizontally above the holding table;
Moving means for moving the bridge structure in a substantially horizontal direction along the surface of the substrate;
With
Substrate processing for forming a layer of the processing liquid on the surface by discharging a predetermined processing liquid from the slit nozzle onto the surface of the substrate while moving the bridging structure in a predetermined direction along the surface of the substrate In the device
An imaging means that is provided above the holding table and captures a surface image on the substrate;
Determination means for determining the presence or absence of streak-like application failure along the predetermined direction with respect to the treatment liquid based on the imaging output of the imaging means;
Further comprising
The image pickup range of the image pickup means is a part of the surface of the substrate, while the image pickup range covers the entire range of the substrate in a direction orthogonal to the predetermined direction. apparatus. The substrate processing apparatus according to claim 8,
The substrate processing apparatus, wherein the imaging range includes a start end of scanning application of the processing liquid in the application unit. The substrate processing apparatus according to claim 8 or 9,
The substrate processing apparatus, wherein the imaging range includes a vicinity of an end of the substrate. The substrate processing apparatus according to claim 10, wherein
The substrate processing apparatus, wherein the imaging range includes a central portion side of the substrate in addition to the vicinity of the end portion. The substrate processing apparatus according to claim 1,
The substrate processing apparatus further comprising a cleaning mechanism for cleaning the slit nozzle when the streak-like application failure is detected by the determination unit. The substrate processing apparatus according to any one of claims 1 to 12,
The substrate processing apparatus further comprising an illuminating unit that illuminates the surface of the substrate so that the processing liquid applied to the surface of the substrate is not exposed when the imaging unit performs imaging. The substrate processing apparatus according to any one of claims 1 to 13,
The substrate processing apparatus, wherein the substrate is a substrate for a flat panel display, and the processing solution is a resist solution.

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