KR100826073B1 - Application device and method of preventing application head clogging - Google Patents

Abstract

In the coating apparatus which controls the discharge amount from the discharge port 5ca of the nozzle plate 5c, and apply | coats a coating liquid to a to-be-coated member, it is opposed to the bottom face of the nozzle plate 5c by control by the controller 9. The thin glass plate 71 of an arrangement | positioning is moved upwards, and it is comprised so that contacting the coating droplet L of the discharge port 5ca is possible. In the discharge port 5ca of the nozzle plate 5c, when the flat plate 71 is brought into contact with the coating droplet L, the coating droplet L attracts the flat plate 71 in contact with the flat plate 71. Since the spreading film is formed between the nozzle plates 5c to form a coating liquid film, the flat plate 71 adheres to the nozzle plate 5c side. As a result, contact of the coating liquid with air in the vicinity of the discharge port 5ca can be avoided, and clogging of the nozzle discharge port due to solidification of the coating liquid can be avoided.

Description

Preventing clogging of applicator and applicator head {APPLICATION DEVICE AND METHOD OF PREVENTING APPLICATION HEAD CLOGGING}

The present invention has a nozzle plate having a discharge port formed therein, which improves a coating device for discharging a coating liquid from a discharge port and applying the coating member to a member to be coated, and an improvement in a method for preventing clogging of a coating head in which a discharge port of the coating liquid is formed on the nozzle plate. It is about.

A liquid crystal display device and a semiconductor device are manufactured through the film-forming process of forming functional thin films, such as an orientation film and a resist, on board | substrates, such as a glass substrate and a semiconductor wafer.

In the film-forming process, in order to form a functional thin film, the coating apparatus which sprays a coating liquid with the inkjet method with respect to the board | substrate which is a to-be-coated member is employ | adopted (for example, refer patent document 1).

FIG. 1 is a configuration diagram showing a conventional coating apparatus for spraying a coating liquid onto a substrate surface by an inkjet method, and FIG. 2 is a side view of the coating apparatus shown in FIG.

As shown in Figs. 1 and 2, a conventional coating apparatus includes a rectangular parallelepiped base (expectation) 1, a pair of guide rails 2 and 2 provided on the base 1, A rectangular table 3 mounted with a substrate W, which is guided and moved on the guide rails 2 and 2, a support body 4 standing up on the base 1, and the support body 4 provided thereon. The controller 6 which collectively controls a plurality of coating heads 5 and a series of coating operations on the substrate W, such as controlling the ejection of the coating liquid from the coating heads 5 and controlling the movement of the table 3. Consists of

The base 1 has a leg 1a at its lower end, and a pair of guide rails 2 via device plates 1b and 1b provided along the longitudinal direction (arrow X direction) at both ends in the width direction of the upper surface. 2) The device is fixed.

Slide members 3a and 3a are provided freely on the pair of guide rails 2 and 2, and the table 3 is attached to these slide members 3a and 3a.

In the table 3, board | substrate holding means, such as a vacuum chuck and an electrostatic chuck, are built-in and the board | substrate W, such as a glass substrate and a semiconductor wafer, can be detachably mounted.

As shown in FIG. 2, the support body 4 is a door-shaped support main body 4a which is provided standing over the guide rails 2 and 2 in the middle part of the longitudinal direction of the base 1, and this door-shaped The support body 4a consists of support members 4b and 4c provided opposite to paired leg bodies, and arms 4d supported at both ends by the support members 4b and 4c.

On the arm 4d of the support 4, a plurality of coating heads 5 (8 in FIG. 2) for discharging the coating liquid by the inkjet method are arranged in the direction indicated by the arrow Y in the drawing.

3 is an enlarged cross-sectional view of the coating head 5 showing a state in which the coating head 5 shown in FIG. 1 is cut in a plane parallel to the ground, and the head body 5a formed in a square cylinder shape. And a flexible plate 5b on which the opening on the head main body 5a is closed, the flexible plate 5b on which the piezoelectric element 5ba is externally attached, and a lower opening of the head main body 5a, on which the opening is closed. It consists of the plate-shaped nozzle plate 5c which formed 5ca, The liquid chamber 5d which accommodates a coating liquid is formed by these head main bodies 5a, the flexible plate 5b, and the nozzle plate 5c. . Moreover, the some discharge port 5ca is arrange | positioned along the longitudinal direction in the nozzle plate 5c, and one piezo element 5ba is arrange | positioned corresponding to each discharge port 5ca.

On one side of the head main body 5a, a coating liquid supply path 5aa leading to the liquid chamber 5d penetrates, and the coating liquid supply path 5aa is connected to a coating liquid supply tank (not shown).

The function of the conventional coating device which consists of the said structure is demonstrated.

In the above configuration, by the control by the controller 6, the table 3 on which the substrate W is placed is moved at a predetermined speed in the direction of the length (shown by the arrow X) of the base 1. The controller 6 drives and controls the piezoelectric element 5ba in accordance with the timing at which the substrate W passes below the application head 5, and vibrates the flexible plate 5b. As a result, pressure is applied to the coating liquid in the liquid chamber 5d, and the coating liquid is in a droplet state from the discharge port 5ca and is discharged toward the lower substrate W. As shown in FIG.

The coating liquid discharged from the discharge port 5ca adheres to the plate surface of the substrate W. As shown in FIG. The applied coating liquid flows on the plate surface and is applied to cover the entire plate surface of the substrate W. The applied coating liquid is dried to form a functional thin film such as an alignment film, a resist, a color filter, and organic electronic luminescence on the substrate W surface.

[Patent Document 1: Japanese Patent Laid-Open No. 2003-103207]

As described above, in the conventional coating apparatus, the coating liquid is discharged from the discharge port (orifice) 5ca of the coating head 5 and applied to the substrate W to be supplied, but to the substrate W to be supplied next. If there is a long time difference until the application, or the state of waiting for a while continues, the coating liquid staying in the discharge port 5ca and contacting air may be dried and solidified, and the discharge port 5ca may be clogged.

In order to prevent drying of the coating liquid and to avoid clogging at the discharge port 5ca, for example, a plate-shaped cap is brought into close contact with the nozzle plate 5c and the discharge port 5ca is blocked to contact the air. I think how to block that.

In order to closely adhere the plate-shaped cap to the nozzle plate 5c and completely prevent contact between the coating liquid and the air at the discharge port, the contact surfaces of both the bottom face of the nozzle plate 5c and the opposing plate-shaped cap surface are highly flat. It becomes a requirement.

For that purpose, it is not easy to make it completely adhere so that air will not enter between a plate-shaped cap surface and the bottom face of the nozzle plate 5c.

Therefore, even if the cap is in close contact with the nozzle plate, it is not possible to completely prevent the coating liquid remaining in the discharge port from contacting the air, and there is a possibility that clogging of the discharge port may occur due to the solidification of the coating liquid. .

Therefore, the present invention can prevent the solidification of the coating liquid at the discharge port of the nozzle plate, and, if necessary, the coating device which is easy to resume application, and the coating which avoids clogging at the discharge port, and is easy to resume application. It is an object to provide a method for preventing clogging of a head.

A first aspect of the present invention has a coating head having a discharge port forming surface on which a discharge port of a coating liquid is formed, wherein the coating liquid is discharged from the discharge port and coated on the member to be coated, wherein the discharge port forming surface A flat plate capable of covering the site where the discharge port is formed, a support for supporting the plate, a moving mechanism for relatively moving the support and the application head at least in a direction orthogonal to the discharge port formation surface, And a control means for controlling the driving and the discharge of the coating liquid from the discharge port, wherein the control means moves the support toward the coating droplet in which the coating liquid is discharged in the convex shape.

A second aspect of the present invention has a coating head having a discharge port forming surface on which a discharge port of a coating liquid is formed, wherein the coating liquid is discharged from the discharge port and coated on a member to be coated, wherein the discharge port forming surface A flat plate capable of covering the site where the discharge port is formed, a support for supporting the plate, a moving mechanism for relatively moving the support and the application head at least in a direction orthogonal to the discharge port formation surface, Drive means and control means for controlling the discharging of the coating liquid from the discharge port, wherein the control means discharges the coating liquid from the discharge port onto the flat plate before moving the flat plate closer to the coating head, Controlling to form a coating liquid film between the discharge port forming surface and the flat plate by the coating liquid discharged on the flat plate It is characterized by.

According to a third aspect of the present invention, in the method for preventing clogging of a coating head in which an ejection opening of a coating liquid is formed on an ejection opening forming surface, a flat plate capable of covering a portion where the ejection opening is formed on the ejection opening forming surface is ejected in a convex shape from the ejection opening. And the flat droplet is brought into close contact with the discharge port forming surface via a coating liquid film formed by spreading the flat liquid droplet between the flat plate and the discharge hole forming surface.

According to a fourth aspect of the present invention, in the method for preventing clogging of a coating head in which an ejection opening of a coating liquid is formed on an ejection opening forming surface, the coating liquid is ejected onto a flat plate that can cover a portion where the ejection opening on the ejection opening forming surface is formed. The flat plate coated with the coating liquid and the application head move closer to the discharge hole forming surface via the coating liquid film formed between the plate and the discharge hole forming surface.

The present invention focuses on the fact that when the flat plate and the coating head are in contact with each other via the coating liquid, the coating liquid spreads to form a coating liquid film between the flat plate and the coating head, and the flat plate adheres to the coating head side via the formed coating liquid film. It is done by.

That is, since the coating apparatus of this invention is equipped with the control means which controls a flat plate to contact a coating head via a coating liquid, a flat plate adheres to the coating head side via the coating liquid film formed by the coating liquid.

Therefore, since the discharge port and the coating liquid in the vicinity thereof maintain contact with air and maintain fluidity, clogging of the discharge port due to solidification of the coating liquid can be avoided.

In addition, according to the method for preventing clogging of the coating head of the present invention, since the flat plate disposed opposite to the coating head is stuck to the coating head side via the coating liquid film, the fluidity of the discharge port and the coating liquid in the vicinity thereof is ensured. In addition, while clogging is prevented, the application operation can be resumed by peeling from the application head of the flat plate.

1 is a front view showing an embodiment of a conventional coating apparatus.

FIG. 2 is a side view of the applicator shown in FIG. 1. FIG.

3 is an enlarged cross-sectional view of the application head shown in FIG. 1.

4 is a front view showing an embodiment of the coating apparatus according to the present invention.

FIG. 5 is a side view of the applicator shown in FIG. 4. FIG.

FIG. 6 is an enlarged front view of main parts of the applicator shown in FIG. 4. FIG.

FIG. 7 is a partially enlarged front view of the coating device shown in FIG. 6.

8 is an explanatory view of the operation of the coating device shown in FIG. 4.

FIG. 9 is a cross-sectional view taken in the direction of the arrow A-A of the operation explanatory diagram shown in FIG. 8C.

Hereinafter, an embodiment of the coating apparatus using the clogging prevention method according to the present invention will be described in detail with reference to FIGS. In addition, the same code | symbol is attached | subjected to the same structure as the conventional coating apparatus shown in FIGS. 1-3, and detailed description is abbreviate | omitted.

FIG. 4 is a front view showing an embodiment of the coating apparatus employing the clogging prevention method according to the present invention, FIG. 5 is a side view of the coating apparatus shown in FIG. 4, and FIG. 6 is the coating apparatus shown in FIG. The enlarged front view of the main part.

4 to 6, the coating apparatus includes a base (expectation) 1, a pair of guide rails 2 and 2 formed in a cross-sectional rectangular shape provided on the base 1, and a substrate W. As shown in FIG. A table 3 mounted on the base 1, a support body 4 standing up on the base 1, an application head 5 mounted on the support body 4 to store a coating liquid, and an application head 5 A flat plate 71 formed slightly larger than the bottom surface in a bottom face (discharge port forming surface) shape and a similar shape, a moving mechanism 8 capable of lifting and lowering the flat plate 71 while supporting the flat plate 71; In addition to the application control of the coating liquid to the coating liquid), the solidification prevention function of the coating liquid by the flat plate 71 and the cleaning (cleaning) function of the coating head 5 by the wiping member 72 are controlled. It consists of the controller 9.

As shown in FIG. 5, the support body 4 is between the door-shaped support main body 4a, the support members 4b and 4c provided in this door-shaped support main body 4a, and the support members 4b and 4c. The application head 5 which consists of the arm 4d supported by the support body 4 and which consists of inkjet type | molds (in this embodiment, eight as shown in FIG. 5) by the arm 4d in the arrow Y direction shown in FIG. It is arranged and arranged.

As enlarged the main part in FIG. 6, a moving mechanism 8 is provided on the right side wall of the table 3 shown in FIG. 4, and the moving mechanism 8 includes a flat plate 71 and a wiping. It is comprised so that the member 72 may be mounted and the flat plate 71 and the wiping member 72 may be moved to the arrow Z (up-down) direction.

The movement mechanism 8 guides to the L-shaped bracket 81 fixed to the table 3, the guide rail 82 provided in the up-down direction to this bracket 81, and this guide rail 82. And a moving box 83 having a box-like shape configured to be movable and moving at the upper end, and a cylinder 84 for driving the moving table 83 in the vertical direction. In addition, the actuating rod 84a of the cylinder 84 has the structure which interposed the elastic member 84aa in the middle, and when the moving table 83 is moved to an up-down direction, by the deformation | transformation of the elastic member 84aa. The movement table 83 itself is configured to be relaxed.

The support table 85 and the wiping member 72 are fixed to the movement table 83, and the support table 85 is provided with the stage 85a which can mount the flat plate 71 detachably. Moreover, the support stand 85 is equipped with the drive part which can raise and lower the stage 85a. Here, FIG. 6 shows a state where the operating rod 84a of the cylinder 84 is in the lower end position, and the stage 85a of the support 85 is located in the elevated end position. Then, from this state, by moving the operating rod 84a of the cylinder 84 to the ascending end position, the flat plate 71 mounted on the stage 85a is the bottom face of the nozzle plate 5c shown in Fig. 8B. It is raised up to a position close to the (discharge port formation surface). In addition, although illustration is abbreviate | omitted, the vacuum chuck is assembled in the stage 85a so that the flat plate 71 can be detachably mounted by the drive control by the controller 9. FIG.

7 shows that under the control of the controller 9, the flat plate 71 placed on the stage 85a of the support 85 faces the bottom of the application head 5 (ie, the nozzle plate 5c). An enlarged view showing the state of being located.

In this embodiment, the flat plate 71 is made of thin transparent glass having a thickness of about 0.3 to 0.7 mm, the shape of which is similar to the bottom shape of the nozzle plate 5c of the application head 5, and the size thereof. As shown in Fig. 7, the outer side has a slightly larger area (Δk) than the nozzle plate 5c.

Therefore, in the embodiment, as shown in Fig. 7, the coating liquid in the droplet state discharged from the convex shape from the opening of the discharge port (orifice) 5ca formed in the central portion of the nozzle plate 5c, that is, the coating liquid L The surface tension of the coating liquid and the flat liquid 71 of the coating liquid when the flat plate 71 placed without being adsorbed to the stage 85a are brought close to each other, and the flat plate 71 comes into contact with the coating liquid L. The application droplet L attracts the lower flat plate 71 while spreading between the contacting flat plate 71 and the nozzle plate 5c by wetness to the flat plate 71, and the flat plate 71 passes through the formed coating liquid film. The focus is on sticking to the bottom surface side of the plate 5c.

In the state where the flat plate 71 adheres to the nozzle plate 5c via the coating liquid film, at least the contact with the air of the discharge port 5ca and the coating liquid in the vicinity thereof is avoided. Solidification can be prevented, fluidity | liquidity of the coating liquid can be ensured, and clogging can be prevented.

Moreover, in the state where the flat plate 71 stuck to the nozzle plate 5c side via the coating liquid film, the coating liquid film sandwiched between the flat plate 71 and the nozzle plate 5c is in contact with air only at the outer circumferential edge. Since the portion to be solidified by a portion is slightly with respect to the portion covered by the plate 71, even if the coating liquid at the outer circumferential edge is solidified, the plate 71 is easily peeled from the nozzle plate 5c to resume application to the substrate W. Is possible.

In this way, the portion where the coating liquid contacts with air and solidifies is limited to the outer circumferential edge portion of the coating liquid film having a large area, and most of the flat plates stuck to the nozzle plate side are via the coating liquid film that maintains fluidity. Since it is in contact with the nozzle plate, the flat plate can be easily peeled off from the nozzle plate side.

In addition, since the part where the coating liquid film contacts with air and solidifies is limited to the outer circumferential edge away from the discharge port 5ca, the solidified material of the coating liquid film is removed at the time of peeling from the nozzle plate 5c of the flat plate 71. Contact with the discharge port 5ca and the discharge port 5ca can be avoided.

Moreover, since the flat plate 71 adheres to the bottom face of the nozzle plate 5c by using the surface tension of the coating liquid and the wetness of the flat plate 71 of the coating liquid, the flat plate 71 is attached to the nozzle plate 5c. No special mechanism is needed to maintain the state. Therefore, troublesome apparatus configuration can be avoided and maintenance work can be performed easily. Moreover, the table 3 can be moved easily with respect to the application | coating head 5, with the flat plate 71 stuck to the nozzle plate 5c. Thereby, the maintenance work of the table 3 and the application head 5 can be made easy, and efficiency can be aimed at.

4 and 7 to 9, the process of sticking the flat plate 71 to the nozzle plate 5c in the coating apparatus of this embodiment will be described in detail.

7 and 8 (a) show that the coating liquid becomes a droplet state, that is, a coating droplet L in a state where the application to the substrate W is stopped, from the outlet of the discharge port 5ca of the nozzle plate 5c. The state discharged in the convex shape is shown. This state is a voltage lower than the voltage supplied to apply the coating liquid to the piezoelectric element 5ba to the substrate W in the stopped state described above, that is, the coating liquid is driven by the piezoelectric element 5ba. It is formed by supplying a voltage that is discharged from the discharge port 5ca but is not emitted from the discharge port 5ca. In this state, the coating droplet L has inherent surface tension, becomes a hemispherical shape, and is discharged in a convex shape from the discharge port 5ca on the bottom of the nozzle plate 5c.

Moreover, by the movement control of the table 3 by the controller 9, the flat plate 71 adsorbed and held on the stage 85a is disposed at a position opposite to the bottom surface of the nozzle plate 5c.

Next, by the drive control of the cylinder 84 by the controller 9, as shown in FIG.8 (b), the stage 85a is raised and the mounted flat plate 71 is apply | coated droplet L Approach and make contact.

During the rise of the stage 85a, the holding of the flat plate 71 by the vacuum chuck of the stage 85a is released until the flat plate 71 comes into contact with the coating droplet L. As shown in FIG.

When the flat plate 71 comes into contact with the coating droplet L, the coating droplet L spreads to form a coating liquid film between the nozzle plate 5c and the flat plate 71, so that the entire flat plate 71 is shown by an arrow. It is pulled in the z direction and separated from the surface of the stage 85a.

As a result, as shown in Fig. 8C, the flat plate 71 adheres to the bottom surface of the nozzle plate 5c via the formed coating liquid film.

FIG. 9 is a cross-sectional view of the arrow direction from the line A-A in FIG. 8 (c). FIG.

As shown in Fig. 9, the coating liquid is spread out between the nozzle plate 5c and the flat plate 71 with the discharge port 5ca positioned at the center, and slightly (Δk) from the bottom of the nozzle plate 5c. Only the coating liquid La located at the outer peripheral edge of the flat plate 71 that is pushed out is in direct contact with air. Moreover, by making the flat plate 71 slightly (△ k) out of the bottom face of the nozzle plate 5c, it can prevent that a coating liquid overflows in the outer position of a coating liquid film.

As shown in FIGS. 8C and 9, in a state where the thin glass plate 71 made of glass is in close contact with the nozzle plate 5c via the coating liquid film, the coating liquid La located at the outer peripheral edge is Even if dried in contact with air and solidified with passage of time, the contact with air is blocked in the vicinity of the discharge port 5ca located at the center of the nozzle plate 5c, so that the fluidity of the coating liquid is maintained. As a result, clogging in the discharge port 5ca due to drying of the coating liquid is avoided.

Moreover, when the flat plate 71 adheres to the nozzle plate 5c side via the coating liquid film, it is preferable that bubbles or the like are not present in the coating liquid film near the discharge port 5ca. In the present embodiment, since the flat plate 71 is made of a transparent glass plate, the worker can visually confirm the presence or absence of the bubble by visually seeing it.

Therefore, when the coating liquid film is photographed with the imaging camera from below through the flat plate 71 stuck to the coating liquid film, and it is detected on the photographed image that bubbles are mixed in the coating liquid film, the control of the controller 9 is performed. By this, the piezo element 5ba can be driven, and bubbles can be removed from the coating liquid film by extrusion of the coating liquid by pressure.

That is, for example, when it is detected that bubbles exist on the right side of the discharge port 5ca shown at the bottom in FIG. 9 based on the captured image of the imaging camera, the piezo corresponding to the bottom discharge port 5ca is detected. The element 5ba is driven to discharge a predetermined amount of coating liquid from the bottom discharge port 5ca to extrude bubbles from the vicinity of the discharge port 5ca to the outer circumferential edge direction of the flat plate 71. In addition, when the presence of a bubble is detected between the discharge port 5ca shown at the bottom in FIG. 9, and the discharge port 5ca on one top, the piezo element 5ba corresponding to the discharge port 5ca at the bottom and top. ) Is discharged, and a predetermined amount of coating liquid is discharged from the two discharge ports 5ca to extrude bubbles from the two discharge ports 5ca toward the outer circumferential edge of the flat plate 71.

At this time, the distance between the bubble and the discharge port 5ca at the proximal position of the bubble is detected based on the captured image of the imaging camera, and based on this distance, the coating liquid is discharged from the discharge port 5ca. In the case of determining whether or not to discharge the coating liquid, the controller 6 may determine whether the discharge amount is determined. That is, the presence of bubbles means the possibility that the coating liquid in contact with the bubbles will solidify. Therefore, even if the position of a bubble is a position where there is no possibility that a defective discharge will occur even if the solidified solution of a coating liquid originates due to a bubble, it is not necessary to remove and remove the bubble. In this case, even if bubbles exist, it is not necessary to discharge the coating liquid from the above-described discharge port 5ca. Therefore, when the bubble is separated from each discharge port 5ca or more by a predetermined distance (set distance), the coating liquid is not discharged from the discharge port 5ca.

Moreover, when a bubble exists within the said set distance, the quantity of the coating liquid required for extruding a bubble to the position separated more than the said set distance is determined based on the distance between the discharge port 5ca and a bubble. The amount of the coating liquid at that time can be calculated by experiment or approximated by geometric calculations based on the distance between the discharge port 5ca and the bubble, the set distance, and the thickness of the coating liquid film. .

By doing in this way, the quantity of the coating liquid discharged in order to remove a bubble can be made to the minimum, and wasteful consumption of a coating liquid can be prevented.

In addition, since the above-mentioned operation cannot be performed after the coating liquid around the bubble causes solidification, the time until solidification occurs in the coating liquid may be obtained beforehand.

In addition, since the coating liquid is newly discharged in the coating liquid film between the nozzle plate 5c and the flat plate 71 by the above operation, even if the flat plate 71 is formed larger by Δk than the bottom of the nozzle plate 5c. It can be considered that the coating liquid overflows from the flat plate 71. In this case, the above-described operation may be performed on the moving table 83, or a supporting plate that replaces the moving table 83 may be disposed to move downward of the application head 5, and then may be performed on this supporting plate.

In addition, when the flat plate 71 may fall from the nozzle plate 5c or the position may shift due to the above-described operation, the flat plate 71 may be replaced by the stage 85a or other supporting means that replaces the stage 85a. What is necessary is just to support.

Moreover, although it demonstrated as an example using an imaging camera, since a yaw needs only to detect a bubble, a line sensor etc. can also be used.

8 (c) and 9, when the application of the coating liquid to the substrate W is to be resumed, the controller 9 operates the vacuum chuck built in the stage 85a. By the suction force of this vacuum chuck 7, the flat plate 71 is held on the stage 85a away from the nozzle plate 5c. Subsequently, the flat plate 71 which stuck to the nozzle plate 5c side via the coating liquid film by the drive control of the cylinder 84 and the downward operation of the stage 85a which adsorbed-held the flat plate 71 via the coating liquid film | membrane is carried out. Peeling is performed.

In the state where the flat plate 71 is peeled off from the nozzle plate 5c side, the discharge port 5ca and the coating liquid (coating liquid film) in the vicinity thereof may remain.

Therefore, in the coating apparatus of this embodiment, at the time of resuming application to the substrate W, the wiping member 72 solidifies the remaining coating liquid on the edge of the nozzle plate 5c and the coating liquid film remaining on the bottom surface. It is designed to be wiped off and removed.

That is, as shown to FIG. 5 and FIG. 6, the wiping member 72 is provided between the table 3 and the support stand 85, and this wiping member 72 is the application head 5 Is made of an elastic member having a width equal to or slightly longer than the length dimension in the width direction (shown by the arrow Y direction). And from the state shown in FIG. 6, first, the stage 85a of the support stand 85 is moved to a lower end position, and it is evacuated. Thereafter, the actuating rod 84a of the cylinder 84 is moved to the ascending end position, and from the state shown in FIG. 6, the table 3 is moved in the direction indicated by the arrow X, so that the wiping member 72 is moved. The tip portion is moved while contacting the bottom face of the nozzle plate 5c, and the solidified material of the coating liquid remaining on the bottom surface of the nozzle plate 5c or the periphery is removed by wiping. Since the wiped coating liquid film and the solidified product of the coating liquid fall in the box-shaped moving table 83, the worker can remove the coating liquid film and the solidified material of the coating liquid collected in the moving table 83.

As described above, in the coating apparatus of the present embodiment, the flat plate 71 made of a thin glass plate having transparency is formed in a similar shape slightly larger than that of the bottom surface of the nozzle plate 5c, and the nozzle plate 5c is formed on the nozzle plate 5c. Since it was arranged so as to face the coating droplets of the discharge port 5ca, the flat plate 71 adhered to the nozzle plate 5c side via the coating liquid film, and the coating liquid in the discharge port 5ca and its vicinity was Solidification can be avoided and clogging at the application head can be prevented.

In addition, in the description of the said embodiment, although the flat plate 71 was made to approach the coating head 5 side, you may comprise so that the coating head 5 may approach the flat plate 71 on the contrary. In addition, the to-be-coated member is not limited to the board | substrate W, For example, printing paper may be sufficient.

Moreover, although the example which peeled off the flat plate which adhered to the nozzle plate via the coating liquid film | membrane using the support stand which supported this flat plate was demonstrated, you may make it peel off using the exclusive peeling apparatus provided separately from this support stand. For example, the peeling apparatus is provided so that a movement to the position which opposes the bottom face of a nozzle plate is provided, and the thing provided with vacuum chucks, such as a suction pad, can be used.

In this case, since the supported flat plate is only attached to the nozzle plate and taken out from the support base, a plurality of flat plates may be laminated and arranged on the support base, and may be attached to the nozzle plate in turn from the flat plate positioned at the uppermost stage. By doing in this way, it is not necessary to supply a flat plate every time affixing on a nozzle plate, and burden of an operator can be reduced.

The flat plate peeled off from the nozzle plate has an advantage of being able to be used in a clean state while repeating the same flat plate because the coating liquid is attached. This cleaning may be performed by a worker by hand using a extraction solvent or the like, or may be performed by providing a cleaning device on the device. As a washing | cleaning apparatus, the holding table which hold | maintains a flat plate, hygroscopic members, such as a wiping cross and sponge which infiltrated a solvent, and a hygroscopic member, such as a dry wiping cross and a sponge, are installed and hold | maintained, for example. The hygroscopic member which soaked the solvent in the surface (cleaning surface) which the coating liquid of the flat plate held on the table adhered was pushed down and wiped, and the coating liquid was wiped off, and then the dry hygroscopic member was pushed down on the flat plate to slide on the flat plate. The thing of the structure which wipes off the remaining solvent can be used.

In addition, in the above-mentioned operation, before wiping the coating liquid attached to the flat plate with the hygroscopic member which infiltrated the solvent, it adheres to the flat plate using the same member formed downward from the wiping member described in the above embodiment. One coating liquid may be wiped off.

In addition, although the flat plate was described as an example of the size of the plate flatly pushing out from the bottom in a shape similar to that of the bottom face of the nozzle plate, the flat plate does not necessarily need to be larger than the bottom face of the nozzle plate, and the shape of the bottom face of the nozzle plate. It doesn't have to be similar to That is, the flat plate has a size capable of covering the discharge port, which is a portion where the discharge port is formed on the bottom surface of the nozzle plate, and its periphery, and can form a coating liquid film between the flat plate and the nozzle plate, whereby It is only necessary to be able to prevent the solidification of the coating liquid from occurring and to prevent the discharge failure caused by the adhesion of the solidified material.

In addition, although the flat plate was formed into the size which covers all the nozzle plates of eight application heads, it demonstrated, but it is not limited to this, It forms in the size corresponding to the size of the nozzle plate in each application head, and forms a flat plate for every application head. You may attach it. Alternatively, one flat plate may be attached to each discharge port.

In this case, the flat plate can be attached in units of the coating head or in the unit of the discharge port. That is, in the example of FIG. 4, 5, it is possible to apply a flat plate only to the coating heads of both ends among eight coating heads, and to apply | coat a coating liquid using the remaining six coating heads.

Therefore, even when the coating liquid is applied to the member to be coated using only a part of the plurality of coating heads or the plurality of discharge ports and the other is allowed to wait, it is preferable that the coating liquid stayed in the discharge port in the air is solidified. Can be prevented. At this time, no special mechanism for maintaining the state of sticking of the flat plate to the nozzle plate is required, so that the coating operation is not restrained by such a mechanism.

It is preferable to use the flat plate as a material with good wettability with a coating liquid or with the surface treatment by which wettability with a coating liquid becomes favorable. By using this, it is possible to smoothly spread the coating droplets discharged from the discharge port in the convex shape between the flat plate and the nozzle plate, and to prevent bubbles from forming in the coating liquid film formed between the flat plate and the nozzle plate.

When forming the coating droplet which discharged the coating liquid in the convex shape in the discharge port, it demonstrated as an example to control and supply the voltage supplied to the piezo element for discharging a coating liquid from a discharge port, For example, you may carry out as follows.

That is, when the coating liquid is supplied from the coating liquid supply tank to the coating head using the principle of siphon, the surface shape (meniscus) of the coating liquid in the opening of the bottom face of the nozzle plate at the discharge port is the height of the bottom surface of the nozzle plate. And the height difference from the liquid level in the coating liquid supply tank. For example, when the liquid level in the coating liquid supply tank is lower than the predetermined height, the surface shape of the coating liquid in the opening of the discharge port becomes concave, and conversely, when it is higher than the predetermined height, it becomes convex. Therefore, the liquid level in the coating liquid supply tank in which the surface shape of the coating liquid in the opening of the discharge port becomes convex is determined in advance by experiment or the like, and the liquid surface height is determined by controlling the rapid discharge of the coating liquid in the coating liquid supply tank. You may adjust to liquid level and form a coating droplet in a discharge port.

In addition, although the coating droplet which discharged the coating liquid in the convex shape was formed in the discharge port as an example, it is only necessary to form a coating liquid film between the nozzle plate bottom surface and the flat plate. The coating liquid may be discharged from the discharge port in a predetermined amount on the flat plate, and a coating liquid film may be formed between the nozzle plate and the flat plate with the coating liquid discharged on the flat plate. Even in this case, as in the above-described embodiment, it is possible to prevent the solidification of the coating liquid from occurring in the vicinity of the discharge port, and the flat plate does not require a special holding mechanism due to the adhesion by the surface tension and the wetness of the coating liquid. Can be attached to the nozzle plate.

Next, the modification of the operation | movement which peels off the flat plate stuck to the nozzle plate is demonstrated.

When peeling the flat plate which stuck to the nozzle plate via the coating liquid film | membrane, although demonstrated as the example which cuts the support stand 85 from the state shown in FIG.8 (c), you may make it operate after raising a support stand once.

6 and 8 (c) of the embodiment will be described below.

In the state shown in FIG. 8 (c), the operating rod 84a of the cylinder 84 is further moved upward from the rising end position described in the above embodiment by a set distance. This set distance adds the distance between the stage 85a of the support base 85 and the flat plate 71 shown in FIG. 8 (c) to the clearance value for making sure that the stage 85a abuts against the flat plate 71. The distance can be calculated from the design data or the like.

By the movement of the set distance of this operating rod 84a, the stage 85a is raised to the position which abuts on the flat plate 71 stuck to the nozzle plate 5c.

At this time, since the actuating rod 84a has the structure which interposed the elastic member 84aa, the impact when the stage 85a abuts on the flat plate 71 is absorbed by this elastic member 84aa. Moreover, even if the set distance is larger than the actual distance between the stage 85a and the flat plate 71 in the state shown in FIG. 8 (c), the flat plate 71 is damaged by the contact of the stage 85a. Can be prevented.

After the operation rod 84a completes the movement of the set distance, that is, at the timing after the stage 85a contacts the flat plate 71, the vacuum chuck built in the stage 85a is operated. Thereby, the flat plate 71 is attracted by the stage 85a. Moreover, you may operate a vacuum chuck from the time of raising the stage 85a.

Thereafter, the working rod 84a is lowered to the lower end position described in the embodiment. As a result, the flat plate 71 is peeled off from the nozzle plate 5c.

In addition, in this modification, it is necessary to stop the operation rod 84a at three positions which contact the flat plate 71 stuck to the nozzle plate 5c other than the lower end position and the elevated end position described in the embodiment. There is. Therefore, as the cylinder 84, the stroke of the operating rod 84a is longer than the cylinder 84 described in the embodiment, and the lower end position of the stroke is described in the embodiment, and the upper end of the flat plate 71 is used. ) To the position where it touches. In addition, what is necessary is to stop it by stopping the movement of the operation rod 84a using the stopper mechanism in the up-end position described in the Example.

In this modification, since the stage 85a is in contact with the flat plate 71, the flat plate 71 can be reliably attracted to the stage 85a by that amount, and the flat plate 71 can be more reliably secured from the nozzle plate 5c. I can peel it off.

Moreover, also in this modification, also in the above-mentioned embodiment, if the flat plate 71 is a magnetic substance or the opposing surface of the nozzle plate 5c is a magnetic substance, you may arrange | position an electromagnet to the stage 85a instead of a vacuum chuck. .

The present invention is not limited to a coating liquid for forming a functional thin film such as an alignment film, a resist, or the like on a substrate such as a glass substrate or a semiconductor wafer, and the coated liquid droplets are formed even when a volatile liquid is used for cleaning the substrate. If it does not volatilize until it contacts a coating droplet, it is applicable.

Since the coating apparatus of this invention is equipped with the control means which controls a flat plate to contact a coating head via a coating liquid, a flat plate adheres to the coating head side via the coating liquid film formed by the coating liquid.

Therefore, since the discharge port and the coating liquid in the vicinity thereof are prevented from contacting with air to maintain fluidity, clogging of the discharge port due to the solidification of the coating liquid can be avoided.

In addition, according to the method for preventing clogging of the coating head of the present invention, the flat plate disposed opposite to the coating head adheres to the coating head side via the coating liquid film, so that fluidity of the discharge liquid and the coating liquid in the vicinity thereof is ensured. While clogging is prevented, the application operation can be resumed by peeling from the application head of the flat plate.

Claims (10)

In the coating device which has a coating head provided with the discharge opening formation surface which formed the discharge opening of the coating liquid, and discharges the said coating liquid from the said discharge opening and apply | coats to a to-be-coated member, A flat plate made of a glass plate having transparency capable of covering a portion where the discharge holes are formed on the discharge hole forming surface; Support for this plate, A moving mechanism for relatively moving the support and the application head in a direction orthogonal to at least the discharge port formation surface; And control means for controlling the driving of this moving mechanism and the discharge of the coating liquid from the discharge port, The control device moves the supporter toward the coating droplet in which the coating liquid is discharged in the convex shape from the discharge port. In the coating device which has a coating head provided with the discharge opening formation surface which formed the discharge opening of the coating liquid, and discharges the said coating liquid from the said discharge opening and apply | coats to a to-be-coated member, A flat plate made of a glass plate having transparency capable of covering a portion where the discharge holes are formed on the discharge hole forming surface; Support for this plate, A moving mechanism for relatively moving the support and the application head in a direction orthogonal to at least the discharge port formation surface; And control means for controlling the driving of this moving mechanism and the discharge of the coating liquid from the discharge port, The control means discharges the coating liquid from the discharge port onto the flat plate prior to moving the flat plate close to the coating head, and the discharge port forming surface and the flat plate by the coating liquid discharged on the flat plate. And coating to form a coating liquid film therebetween. The method according to claim 1 or 2, The said flat plate was formed in the similar shape larger than the shape of the said discharge port formation surface, The coating apparatus characterized by the above-mentioned. delete The method according to claim 1 or 2, It has an imaging device which can image the said discharge port formation surface, The control means further controls the presence or absence of bubbles in the coating liquid film formed between the discharge opening forming surface and the glass plate by contacting the glass plate with the coating droplet based on the captured image of the discharge opening forming surface by the imaging device. And when a bubble is detected as a result of the detection, a predetermined amount of coating liquid is discharged from the discharge port. The method according to claim 5, The control means calculates a distance between the discharge port and bubbles in the coating liquid film based on the captured image of the discharge port formation surface by the imaging device, and applies the coating to discharge from the discharge port based on the calculated distance. An applicator characterized by varying the amount of liquid. In the method for preventing clogging of a coating head in which a discharge hole of a coating liquid is formed on a discharge hole forming surface, A coating formed by contacting a flat plate capable of covering a portion on which the discharge port is formed on the discharge port forming surface with a coating droplet formed by discharging in a convex shape from the discharge port, and spreading the flat plate between the flat plate and the discharge port forming surface. It adheres to the said discharge port formation surface via a liquid film, detects the presence or absence of the bubble in the said coating liquid film | membrane through the said flat plate, and discharges a predetermined amount of coating liquid from the said discharge port when the bubble is detected. How to prevent clogging of the application head. In the method for preventing clogging of a coating head in which a discharge hole of a coating liquid is formed on a discharge hole forming surface, The coating liquid is discharged onto a flat plate that can cover a portion where the discharge hole is formed on the discharge hole forming surface, and is spread between the flat plate and the discharge hole forming surface by an approach movement between the flat plate coated with the coating liquid and the coating head. The plate is brought into close contact with the discharge port forming surface via the formed coating liquid film, the presence or absence of bubbles in the coating liquid film is detected through the flat plate, and when the bubbles are detected, a predetermined amount of coating liquid is discharged from the discharge port. A clogging prevention method of an application head, characterized in that. delete The method according to claim 7 or 8, Peeling off the flat plate adhered to the discharge hole forming surface through the coating liquid film, and then removing the coating liquid adhered to the discharge hole forming surface.

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