JP2001157863A - Coater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coater capable of detecting the clogging or the like of an ejection hole of a nozzle for applying a coating liquid. SOLUTION: A resist liquid is discharged from a nozzle 40 of each coating head 36, which is disposed above a monitoring part 44 located at a standby position 41, onto each pressure sensor 46. When any one of the pressure sensors 46 detects an abnormal value of pressure, it is judged that abnormality, such as clogging, is generated in any one of the ejection holes of the nozzles 40, and the nozzles 40 are cleaned in a cleaning part 45.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of processing, for example, a semiconductor wafer or a glass substrate used for a liquid crystal display by using a photolithography technique. The present invention relates to a coating apparatus for applying a coating liquid such as a coating liquid.

[0002]

2. Description of the Related Art In a manufacturing process of a liquid crystal display device, for example, in order to form an ITO thin film or an electrode pattern on a glass substrate, a circuit pattern or the like is formed by using the same photolithography technology used in a semiconductor manufacturing process. Is subjected to a reduced exposure, transferred to a photoresist, and developed.

[0003] Such a series of processing includes, for example, a cleaning device, an adhesion processing device, a cooling processing device, a resist coating device, a heat treatment device, and a developing device along a transport path along which a transport device for transporting a glass substrate can travel. This is performed by a coating and developing system having a configuration in which devices and the like are arranged.
In such a coating and developing system, the glass substrate is cleaned by a cleaning device, the glass substrate is subjected to a hydrophobic treatment by an adhesion processing device, cooled by a cooling device, and then cooled by a resist coating device. A photoresist film is applied and formed. After that, the photoresist film is heated by a heat treatment device, subjected to a pre-bake treatment, and then cooled, and is exposed to a predetermined pattern by an exposure device connected to the system, and the exposed glass substrate is developed by a developing device. After applying and developing the solution, the developer is washed away with a rinse solution,
Post bake processing is performed, and a series of steps is completed.

[0004]

In the above-described resist coating apparatus, for example, a spin coating method is used in which a glass substrate is placed on a spin chuck, rotated, and a resist solution is supplied to the center of rotation. When the resist solution is applied by spin coating, there is a problem that a considerable amount of the resist solution supplied onto the glass substrate scatters outside the glass substrate due to centrifugal force and is wasted.

Therefore, the present inventors scan a nozzle for discharging a resist solution on the surface of a glass substrate by scanning.
A technique is proposed in which a resist solution is applied only to a necessary area as much as possible, and the waste of the resist solution is eliminated.

However, in the nozzle having such a configuration,
When the supply of the resist liquid from the nozzle is stopped, the diameter of the discharge hole cannot be so large in order to prevent the resist liquid from dripping from the discharge hole of the nozzle, so that the discharge hole of the nozzle is easily clogged. There is a problem. Then, such clogging of the discharge holes of the nozzles can be detected by visual confirmation or by finding a break in the coating film on the substrate.However, until the detection, the coating becomes poor and the yield is reduced. In addition, if such clogging is overlooked, a large amount of coating failure will occur.

The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a coating apparatus capable of quickly detecting a clogging of a discharge hole of a nozzle for applying a coating liquid. .

[0008]

Means for Solving the Problems To solve the above problems, a coating apparatus of the present invention comprises a holding member for holding a substrate,
A nozzle provided with a discharge hole for discharging the coating liquid toward the surface of the held substrate; and monitoring means for monitoring a state of the coating liquid discharged from the discharge hole.

In the present invention, since the monitoring means for monitoring the state of the coating solution discharged from the discharge hole of the nozzle is provided, the clogging of the discharge hole of the nozzle can be quickly detected by the monitoring means. .

[0010] The coating apparatus of the present invention is provided between an application position where the nozzle applies the application liquid to the substrate held by the holding member and a standby position where the nozzle waits when the application liquid is not applied. It has a conveying means for conveying the nozzle, and the monitoring means is a pressure sensor which is disposed at the standby position and detects a discharge pressure of the application liquid discharged from the nozzle.

In the present invention, the clogging of the nozzle orifice of the nozzle can be detected before application by detecting the discharge pressure of the application liquid discharged from the nozzle by the pressure sensor before application. Accordingly, it is possible to eliminate coating defects due to clogging of the discharge holes of the nozzles. In addition, by discharging the coating liquid from the nozzle before the coating as described above, the discharging operation of the old coating liquid remaining at the tip of the nozzle performed before the coating can be performed at the same time. Further, when there are a plurality of discharge holes, clogging of each discharge hole can be individually detected by providing a pressure sensor for each discharge hole. Therefore, as one mode of the present invention, the nozzle is provided with a plurality of the ejection holes.

In the coating apparatus of the present invention, the monitoring means is provided integrally with the nozzle, irradiates the coating liquid discharged from the nozzle with light, and based on the reflected light or transmitted light, It is an optical sensor that monitors the state of the coating liquid discharged from the discharge hole.

In the present invention, for example, while the discharge liquid is being discharged from the nozzle, the state of the coating liquid discharged from the discharge hole is monitored by an optical sensor to monitor the state of the discharge liquid during discharge. It is possible to detect clogging or the like of the discharge hole of the nozzle. Further, by providing such an optical sensor integrally with the nozzle, a special place for detecting clogging of the nozzle or the like becomes unnecessary. Furthermore, when there are a plurality of discharge holes, it is possible to individually detect clogging of each discharge hole by providing an optical sensor for each discharge hole. But it is advantageous. As one mode of the present invention, the nozzle is provided with a plurality of the ejection holes.

The coating apparatus of the present invention has a supply path through which the coating liquid is fed to the nozzle, and the monitoring means is a pressure sensor for detecting a supply pressure of the coating liquid in the supply path. Features.

According to the present invention, clogging of the discharge holes of the nozzles can be detected only by providing a pressure sensor in the supply path through which the coating liquid is fed to the nozzles. Therefore, the configuration is very simple.

According to the present invention, there is provided a coating apparatus comprising: means for judging whether the state of the discharge hole is deteriorated based on the monitoring result by the monitoring means; and determining whether the state of the discharge hole is deteriorated. And a washing means for washing the nozzle.

In the present invention, for example, when clogging of the discharge hole of the nozzle is detected, the nozzle is cleaned without manual operation. Therefore, maintenance of the nozzle can be performed without any trouble.

[0018] The coating apparatus of the present invention is characterized in that the cleaning means is an ultrasonic vibrator arranged near a discharge hole of the nozzle. Thereby, space for cleaning can be saved.

The coating apparatus of the present invention is characterized in that the cleaning means is a container storing the cleaning liquid, and the nozzle is immersed in the cleaning liquid in the container. Thereby, cleaning can be performed reliably. In order to further enhance the cleaning effect, the present invention may be combined with the ultrasonic vibrator having the above configuration.

The coating apparatus of the present invention further comprises means for monitoring the state of the coating liquid discharged from the discharge holes of the nozzles cleaned by the cleaning means, and performing predetermined notification when the state does not improve. It is characterized by the following. This can prevent unnecessary cleaning of ineffective cleaning.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

In the following embodiments, a case will be described in which the present invention is applied to a coating and developing system for forming a resist film on a glass substrate and developing the exposed glass substrate.

First, a first embodiment will be described.

FIG. 1 is a perspective view showing the configuration of the coating and developing system according to the first embodiment.

The coating and developing system 1 shown in FIG. 1 includes a loader unit 2 for loading and unloading a glass substrate G (hereinafter, referred to as “substrate G”), a first processing unit 3 for the substrate G, and a relay. A second processing unit 5 connected to the first processing unit 3 via the unit 4
It is mainly composed of Note that an exposure device 6 for exposing a predetermined fine pattern on the resist film via the transfer unit 7 can be connected to the second processing unit 5.

The loader unit 2 is provided with a cassette station 10 which includes a cassette 11 for storing unprocessed substrates G and a cassette 12 for storing processed substrates G.
And a plurality of them can be freely mounted. Cassettes 10, 11
And a substrate loading / unloading tweezers 13 which can be moved and rotated (θ) in the horizontal (X, Y) direction and the vertical (Z) direction so as to carry in and out the substrate G.

In the first processing unit 3, a substrate G is brush-washed on one side of a transfer path 16 in which a main substrate transfer device 15 capable of moving in the X, Y, and Z directions and rotatable by .theta. Brush cleaning device 17 and developing device 18 are arranged side by side,
On the other side of the transport path 11, an adhesion treatment device 19 for hydrophobizing the surface of the substrate G, a heat treatment device 20 for performing post-baking for heating after the development process, and a cooling treatment device 21 for cooling the substrate G to a predetermined temperature are provided. They are arranged in multiple stages.

Similarly to the first processing unit 3, the second processing unit 5 includes a transfer path 23 in which a main substrate transfer unit 22 capable of moving in the X, Y, and Z directions and rotating θ can be moved. On one side, a coating apparatus 24 is arranged, and on the other side of the transport path 23, a heat treatment apparatus 20 for performing prebaking for heating the substrate G after applying the resist liquid, and a cooling processing apparatus 21 are arranged in multiple stages.

The transfer section 7 includes a cassette 25 for temporarily holding the substrate G, a transfer tweezers 26 for taking the substrate G in and out of the cassette 25,
Is provided.

FIG. 2 is a perspective view showing the structure of the above-described coating apparatus 24.

Substantially at the center of the coating device 24, a substrate G
A holding plate 31 is provided as a holding member for holding. A plurality of support pins (not shown) for supporting the substrate G from the surface of the holding plate 31 are arranged so as to be able to protrude and retract. Then, in a state where the support pins protrude from the surface of the holding plate 31, the support pins are transferred to and from the main substrate transfer device 22 through the opening 32 of the coating device 24.
The coating process is performed in a state where the substrate G is placed on the holding plate 31 while being immersed from the surface of the substrate 1.

On both sides of the coating device 24 along the X direction,
For example, an X-direction conveying member 3 constituted by an endless belt
The Y-direction transport member 34 is disposed so as to straddle between the X-direction transport members 33. One X
At one end of the directional transport member 33, a driving unit 35 for driving the X directional transport member 33 formed of, for example, an endless belt to transport the Y directional transport member 34 in the X direction is provided. A transport unit 37 that transports the application head 36 in the Y direction along the Y-direction transport member 34 and that moves the coating head 36 up and down in the Z direction is movably disposed on the Y-direction transport member 34.

A standby position 41 is provided adjacent to one side of the holding plate 31 where the coating head 36 waits when the resist liquid is not applied to the substrate G.
Then, the coating head 36 is transported between the holding plate 31 and the standby position 41 by the transport system described above.

FIG. 3 is a perspective view showing the structure of the coating head 36 described above. FIG. 4 is a schematic front view of the state where the coating head 36 is at the standby position 41, and FIGS.
FIG.

A plurality of, for example, five discharge holes 39 for discharging a resist solution as a coating solution toward the surface of the substrate G held by the holding plate 31 are arranged in a lower portion of the main body 38 of the coating head 36. Nozzle 40 is provided. A resist solution is supplied to the nozzle 40 from a resist solution storage tank 43 via a pump 42.

On the other hand, at the standby position 41, a monitoring section 44 provided with the monitoring means according to the present invention and a cleaning section 45 provided with the cleaning means according to the present invention are arranged adjacent to each other.

In the monitoring section 44, as shown in FIG. 5, when the coating head 36 is transported to the upper part, a pressure sensor 46 for detecting the discharge pressure of the resist liquid discharged from each discharge hole 39 of the nozzle 40 is provided. Five rows are provided corresponding to the respective discharge holes 39. Note that the pressure sensor 46 is
Is discharged to the outside through an exhaust hole 47. In the cleaning section 45, a container 48 in which, for example, acetone as a cleaning liquid is stored. As shown in FIG. 6, when cleaning the nozzle 40, the coating head 36 is moved above the container 48 and the container 48 is moved from that position until the nozzle 40 is immersed in the cleaning liquid.
It is designed to descend inside.

As shown in FIG. 4, the result detected by the pressure sensor 46 is sent to the control unit 49,
Controls the transport system of the pump 42 and the coating head 36 based on the detection result.

Next, the operation of the coating and developing system 1 configured as described above will be described.

First, after the unprocessed substrate G accommodated in the cassette 11 is taken out by the loading / unloading tweezers 13 of the loader unit 2, the main substrate transfer device 15 of the first processing unit 3
And transported into the brush cleaning device 17. The substrate G that has been brush-cleaned in the brush cleaning device 17 is subjected to a hydrophobic treatment by an adhesion processing device 19, cooled by a cooling processing device 21, and then placed on the relay unit 4.

The main substrate transfer device 22 of the second processing section 5 receives the substrate G and transfers it to the coating device 24.

In the coating device 24, support pins (not shown)
Receives the substrate G from the main substrate transfer device 22 while protruding from the surface of the holding plate 31 and sinks from the surface of the holding plate 31 to place the substrate G on the holding plate 31.

At this time, the coating head 36 is on the monitoring unit 44 at the standby position 41 as shown in FIG. Here, FIG. 7 is a flowchart showing the operation when the coating head 36 is at the standby position 41.

The resist liquid is discharged from the nozzle 40 of the coating head 36 on the monitoring unit 44 at the standby position 41 toward each pressure sensor 46 (step 701). And
When a normal value of pressure is detected by each pressure sensor 46 (step 702), the count value of the counter in the control unit 49 described later is cleared (step 70).
3) Start the resist coating operation. On the other hand, when the pressure of an abnormal value (including 0) is detected by any of the pressure sensors 46 (step 702), more specifically, for example, when the pressure is not detected or lower than normal, It is determined that an abnormality such as clogging has occurred in any of the discharge holes 39, and the cleaning unit 45 performs the cleaning process of the nozzle 40 (step 704). And
When the cleaning process is completed, the count value of the counter in the control unit 49 is increased by one (in this case, the counter value is 1) (step 705), and the operations of steps 701 and 702 are executed again. The cleaning process in step 704 is repeated until no abnormal pressure is detected.
If the count value of the counter in the control unit 49 is 5, that is, if an abnormality in pressure is detected even after repeating the cleaning process five times (step 706), it is determined that clogging of the nozzle 40 and the like in the above-described cleaning process will not be cured. Judgment is made and an alarm is issued from a display unit, a speaker or the like (not shown) (step 7).
07). By issuing such an alarm, it is possible to prevent unnecessary cleaning of ineffective cleaning. In the above example, the alarm is issued at the counter value of 5, but this is merely an example, and it is needless to say that the alarm value may be smaller or larger.

When the nozzle 40 is normal and the clogging or the like is cured by the above operation, the resist coating operation is started.

That is, while the coating head 36 is scanned by the scanning of the scanning mechanism constituted by the X-direction conveying member 33, the Y-direction conveying member 34, the driving section 35 and the conveying section 37,
The resist liquid is supplied from the respective discharge holes 39 of the nozzle 40 toward the surface of the substrate G. As an example of the scanning, the nozzle 4
The direction in which the 0 ejection holes 39 are arranged is adjusted so as to be parallel to the X direction, and the coating head 36 is transported in the Y direction from the one end of the substrate G in the X direction by the scanning mechanism. Next, the coating head 3
6 is moved by the scanning mechanism in the X direction by the application pitch of the entire nozzle 40, and the coating head 36 is transported in the Y direction by the scanning mechanism. Hereinafter, by repeating such scanning, the application head 36 is scanned over the entire surface of the substrate G, and the resist liquid is applied over the entire surface of the substrate G.

Next, the substrate G coated with the resist solution is heated and baked by the heat treatment apparatus 20.
After being cooled by the cooling processing device 21, a predetermined pattern is exposed by the exposure device 6. Then, the substrate G after the exposure is transported into the developing device 18, and after being developed with the developing solution, the developing solution is washed away with the rinsing solution, and the developing process is completed. After that, the substrate G is heated and baked by the heat treatment apparatus 20, and after being cooled by the cooling processing apparatus 21, the processed substrate G is stored in the cassette 12 of the loader unit 1, and a series of processing is completed.

As described above, according to the coating apparatus 24 in the coating and developing processing system 1 according to the present embodiment, the standby position 4
The resist liquid is discharged from the nozzle 40 of the coating head 36 on the first monitoring unit 44 toward each pressure sensor 46,
If an abnormal value of pressure is detected by any of the pressure sensors 46, it is determined that an abnormality such as clogging has occurred in any of the discharge holes 39 of the nozzle 40, and the cleaning unit 45 cleans the nozzle 40. Since the process is performed, it is possible to eliminate a failure in applying the resist liquid due to clogging of the discharge hole 39 of the nozzle 40 without manual intervention. Further, by discharging the resist liquid from the nozzle 40 before the coating in this way, the nozzle 4 performed before the coating is discharged.
The operation of discharging the old resist solution remaining at the leading end of the zero can be simultaneously performed.

In the above-described embodiment, the nozzle 40
Was washed with a cleaning liquid. However, as a second embodiment, for example, as shown in FIG.
The nozzle 40 can be cleaned by providing an ultrasonic vibrator 81 around the nozzle and supplying a high frequency from a predetermined high frequency source. Accordingly, it is not necessary to provide the cleaning unit 45 at the standby position 41. Here, when the resist liquid is supplied to the nozzle 40, the resist liquid excited by the ultrasonic vibration passes through the nozzle 40, thereby preventing the nozzle from being clogged. Further, by adopting a configuration in which the cleaning liquid passes through the nozzle 40 and is discharged from the discharge port instead of the resist liquid, the cleaning performance of the nozzle 40 can be improved.

In the above-described embodiment, the monitoring unit 44
The clogging of the nozzle 40 and the like are detected by the pressure sensor 46 disposed in the nozzle 40. However, as a third embodiment, as shown in FIG. The monitoring means may be configured by integrally providing an optical sensor 91 that irradiates light toward the liquid and detects clogging of the ejection hole 29 based on the reflected light. In addition, as the optical sensor, for example, a pair of a light emitting element and a light receiving element may be arranged so as to sandwich the ejection hole 39, and the clogging of the ejection hole may be detected by transmitted light.
This eliminates the need to provide the monitoring unit 44 at the standby position 41.

Further, as a fourth embodiment, as another example of the monitoring means, as shown in FIG. Pressure sensor 10 for detecting pressure
2 may be arranged.

As a fifth embodiment, as shown in FIGS. 11 and 12, the nozzle 140 has a two-layer structure in which the base 137 and the tip 138 are adjacent to each other, and the tip 138 of the nozzle 140 extends along the base 137. It may be designed to be slidable. In this case, a discharge hole 139 is provided at the tip 138, and the resist solution is discharged through a hollow portion provided at the base 137 and a discharge port 139 provided at the tip 138. In the present embodiment, the tip 138 of the nozzle 140 is made slidable so that the tip 138 can be slid.
When cleaning is performed, both the surface on the base 137 side of the discharge port 139 and the surface on the opposite side to the base 137 can be immersed in the cleaning liquid. Accordingly, the surface of the discharge port 139 on the base 137 side where cleaning residue tends to occur can be sufficiently cleaned. Also,
Tip 138 may be removable.

In the second embodiment, the ultrasonic vibrator 81 is provided around the discharge hole 39. However, as a sixth embodiment,
As shown in FIG. 13, an ultrasonic vibration horn composed of a vibration horn 110 and an ultrasonic vibrator 111 is pressed against the nozzle 40 in a direction perpendicular to the scan direction of the nozzle 40, The chemical supplied from the supply pipe 109 may be discharged. When a resist solution is used as the chemical solution, the resist solution excited by the ultrasonic vibration passes through the nozzle, so that clogging can be prevented. Further, when a cleaning liquid such as acetone is used as a chemical solution, the cleaning effect is improved by ultrasonic vibration as compared with the case where only the cleaning liquid is used.

In the second embodiment, the ejection holes 39 are used.
The ultrasonic vibrator 81 is provided around the container, but as a seventh embodiment, as shown in FIG.
81 may be provided and the nozzle 40 may be ultrasonically cleaned.

Further, as an eighth embodiment, as shown in FIG.
Solution or cleaning solution / nitrogen gas supply pipe 11 through
Alternatively, the cleaning liquid may be supplied through the nozzle 6. The resist liquid supply pipe 117 and the cleaning liquid / nitrogen gas supply pipe 116 are connected to a switching valve 119. By switching the switching valve 119, whether the resist liquid is supplied into the nozzle 40 or the cleaning liquid or the nitrogen gas is supplied. Is selected. The cleaning liquid or nitrogen gas supply pipe 1 is connected to the cleaning liquid / nitrogen gas supply pipe 116 through the cleaning liquid supply pipe 120.
Nitrogen gas is supplied via 21. Cleaning liquid supply pipe 12
0 and the nitrogen gas supply pipe 121 are connected to the switching valve 118.
The switching of the switching valve 118 selects whether the cleaning liquid or the nitrogen gas is supplied to the cleaning liquid / nitrogen gas supply pipe 116. Further, an exhaust pipe 123 for exhausting the gas in the nozzle 40 is provided, and the exhaust of the gas in the nozzle 40 is adjusted by opening and closing the valve 122.

In the eighth embodiment, when discharging the resist liquid, the valve 122 is closed, and the switching valve 119 is switched so that the resist liquid from the resist liquid supply pipe 117 is supplied into the nozzle 40. . When the discharge port 39 of the nozzle 40 is clogged, the switching valve 119 is switched, and the cleaning liquid is supplied into the nozzle 40 via the cleaning liquid / nitrogen gas supply pipe 116. Thus, the fixed resist causing the clogging is dissolved and removed by the cleaning liquid. afterwards,
The switching valve 118 is switched, and nitrogen gas is supplied to the cleaning liquid / nitrogen gas supply pipe 116. The nitrogen gas is supplied into the nozzle 40 through the switching valve 119, and the cleaning liquid in the nozzle is dried by the nitrogen gas. When the nitrogen gas is supplied, the valve 122 is opened, and the inside of the nozzle 40 is vented through the exhaust pipe 123.

In the first embodiment, a pressure sensor is provided for each discharge port. However, as shown in FIG. 16, as a ninth embodiment, a nozzle 40 has a discharge hole 39 for each of three divided areas. Three pressure sensors 146 may be provided for each of these areas. In this case, by making the ejection pressure uniform for each region, the resist liquid can be uniformly applied on the substrate in the plane.

Further, a CCD camera may be provided as monitoring means. In this case, the image information of the resist liquid discharged from each discharge hole of the nozzle by the CCD camera is obtained. Then, for example, by taking two pieces of image information into the image processing apparatus, and performing a process such as binarization on the subtracted difference image to perform a pattern matching method for examining the difference between the two pieces of image information, By comparing the ejection state of the resist liquid in the ejection holes, clogging of the ejection holes can be detected. Alternatively, as a comparison pattern, a pattern obtained by performing image processing on image information when there is no clogging of the ejection holes is registered in the image processing apparatus, and a pattern obtained by performing image processing on image information obtained from a CCD camera is the same as a previously registered pattern. By determining whether they match, it is possible to detect clogging of the ejection holes.

Further, in the present invention, for example, the substrate may be not only a glass substrate but also a semiconductor wafer.
The coating liquid may be not only a resist liquid but also a coating liquid for an insulating film.

[0060]

As described above, according to the present invention,
It is possible to quickly find out clogging of a discharge hole of a nozzle for applying a coating liquid. Further, such defects can be cured without manual intervention.

[Brief description of the drawings]

FIG. 1 is a perspective view of a coating and developing processing system according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a coating apparatus in the coating and developing processing system shown in FIG.

FIG. 3 is a perspective view showing a configuration of a coating head in the coating apparatus shown in FIG.

FIG. 4 is a schematic front view showing a state where the coating head shown in FIG. 2 is at a standby position.

FIG. 5 is a side view of the application head shown in FIG. 4 (part 1).

FIG. 6 is a side view (part 2) of the coating head shown in FIG.

FIG. 7 is a flowchart showing an operation of the coating apparatus shown in FIG. 2;

FIG. 8 is a side view of a coating head according to a second embodiment.

FIG. 9 is a side view of a coating head according to a third embodiment.

FIG. 10 is a front view of a coating head according to a fourth embodiment.

FIG. 11 is a perspective view of a coating head according to a fifth embodiment.

FIG. 12 is a partial cross-sectional view of the coating head shown in FIG.

FIG. 13 is a perspective view of a coating head according to a sixth embodiment.

FIG. 14 is a side view of a coating head according to a seventh embodiment.

FIG. 15 is a side view of a coating head according to an eighth embodiment.

FIG. 16 is a front view of a coating head according to a ninth embodiment.

[Explanation of symbols]

 Reference Signs List 24 coating device 31 holding unit 36 coating head 39 discharge hole 40 nozzle 41 standby position 44 monitoring unit 45 cleaning unit 46 pressure sensor 48 container 81 ultrasonic transducer 91 optical sensor 101 supply path 102 pressure sensor G glass substrate

Claims (21)

[Claims] 1. A holding member for holding a substrate, a nozzle provided with a discharge hole for discharging a coating liquid toward a surface of the held substrate, and a state of the coating liquid discharged from the discharge hole is monitored. A coating device comprising: 2. A transport for transporting a nozzle between a coating position where the coating liquid is applied from the nozzle to a substrate held by the holding member and a standby position where the nozzle waits when the coating liquid is not applied. 2. The coating apparatus according to claim 1, further comprising a unit, wherein the monitoring unit is a pressure sensor disposed at the standby position and configured to detect a discharge pressure of the coating liquid discharged from the nozzle. 3. 3. The coating apparatus according to claim 2, wherein the nozzle has a plurality of the discharge holes. 4. The coating apparatus according to claim 3, wherein said pressure sensor is provided for each of said discharge holes. 5. The coating apparatus according to claim 2, wherein the nozzle is provided with a plurality of the ejection holes for each of a plurality of divided regions, and the pressure sensor is provided for each of the regions. 6. The monitoring means is provided integrally with the nozzle, irradiates the coating liquid discharged from the nozzle with light, and discharges the coating liquid from the discharge hole based on the reflected light or transmitted light. The coating device according to claim 1, wherein the coating device is an optical sensor that monitors a state of the coating solution. 7. The coating apparatus according to claim 1, wherein the monitoring unit includes a CCD camera that captures image information of the coating liquid discharged from the discharge port. 8. The coating apparatus according to claim 7, wherein the image information is subjected to image processing. 9. The coating apparatus according to claim 8, wherein in the image processing, the image information is binarized. 10. The coating apparatus according to claim 8, wherein in the image processing, the image information is subjected to a pattern matching process. 11. A method according to claim 11, further comprising a supply path through which the application liquid is pressure-fed to the nozzle, wherein the monitoring means is a pressure sensor for detecting a supply pressure of the application liquid in the supply path. 1
3. The coating device according to claim 1. 12. The coating apparatus according to claim 6, wherein the nozzle is provided with a plurality of the discharge holes. 13. A means for judging whether or not the state of the discharge hole is deteriorated based on a monitoring result by the monitoring means, and cleaning the nozzle when it is judged that the state of the discharge hole is deteriorated. The coating device according to claim 1, further comprising a cleaning unit that performs cleaning. 14. The coating apparatus according to claim 13, wherein said cleaning means is an ultrasonic vibrator arranged near a discharge hole of said nozzle. 15. The coating apparatus according to claim 13, wherein the cleaning unit is a container storing the cleaning liquid, and wherein the nozzle is immersed in the cleaning liquid in the container. 16. The coating apparatus according to claim 15, wherein an ultrasonic vibrator is provided in the container. 17. The nozzle includes a tip having the discharge hole, and a base having a hollow portion adjacent to the tip and communicating with the discharge hole, wherein the tip extends along the base. The coating device according to claim 15, wherein the coating device is slidable. 18. The nozzle comprises: a tip having the discharge hole; and a base having a hollow portion adjacent to the tip and communicating with the discharge hole. The tip is detachable from the base. The coating device according to claim 15, wherein the coating device is provided. 19. The coating apparatus according to claim 13, wherein said cleaning means is a cleaning liquid supply pipe for supplying a cleaning liquid into said nozzle. 20. A coating liquid supply pipe for supplying the coating liquid into the nozzle, supply of the cleaning liquid from the cleaning liquid supply pipe to the nozzle, and supply of the coating liquid from the coating liquid supply pipe to the nozzle. 20. The coating apparatus according to claim 19, further comprising: a switching unit that switches the application. 21. The apparatus according to claim 21, further comprising means for monitoring a state of the coating liquid discharged from the discharge hole of the nozzle cleaned by the cleaning means, and performing a predetermined notification when the state does not improve. The coating device according to claim 13.