JP2011167612A - Slit nozzle cleaning device and coating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To automatically and efficiently clean the inside of a slit of a slit nozzle while suppressing the occurrence of particles. <P>SOLUTION: The slit nozzle cleaning device 70 is constituted of a nozzle cleaning unit 56, an X-direction moving part 54 for moving the whole priming treatment part to a substrate transporting direction (X-direction) and a Y-direction moving part 60 for moving the nozzle cleaning unit 56 to a nozzle longitudinal direction (Y-direction) in a casing. The nozzle cleaning unit 56 is provided with a thin-plate like scraper 74 to be inserted and withdrawn to and from the slit 32a of the slit nozzle 32 from the outside, a holding part 76 holding the scraper 74, a lifting mechanism 78 for moving the scraper 74 integrated with the holding part 76 in the discharge direction of the slit nozzle 32 and a rotating mechanism for rotating the scraper 74. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a spinless coating apparatus, and more particularly to a slit nozzle cleaning apparatus for cleaning the inside of a slit nozzle used in a spinless coating process.

  In a photolithography process in a manufacturing process of a flat panel display (FPD) such as an LCD, a long slit nozzle having a slit-shaped discharge port is moved relative to a target substrate such as a glass substrate, A spinless coating method in which a coating solution such as a processing solution or a chemical solution such as a resist solution is applied on a substrate is often used.

  In a typical spinless coating method, the slit nozzle is moved in one horizontal direction perpendicular to the longitudinal direction of the nozzle while the resist solution is ejected from the slit nozzle onto the substrate fixedly placed on the stage. Let If it does so, the resist liquid which overflowed on the board | substrate from the discharge port of the slit nozzle will extend flat back of a nozzle, and a resist coating film will be formed in the one surface of a board | substrate (for example, patent document 1).

  As another typical spinless coating method, a levitation transport method is often used in which a substrate is transported in a horizontal direction (stage longitudinal direction) while being floated on the stage. In this method, a long slit nozzle installed above the levitation stage discharges a resist solution in a strip shape toward the substrate passing directly below it, so that the substrate from the front end to the rear end in the substrate transport direction. A resist coating film is formed on the entire surface of the substrate (for example, Patent Document 2).

Japanese Patent Laid-Open No. 10-156255 Japanese Patent Laid-Open No. 2005-236092

  In the slit nozzle used for the spinless coating process as described above, the gap of the slit for discharging the resist solution is very narrow (usually 100 μm or less), so that the resist is gelled in the resist supply tube or the slit nozzle. The solidified product is easily clogged in the slit, and if the resist solidified product is clogged somewhere in the slit, the outflow of the resist solution (that is, supply to the substrate) is lacking at that point, and it is straight on the resist coating film in the coating scanning direction. An elongated streaky coating unevenness occurs.

  Conventionally, in order to prevent the resist solidified material from being clogged in the slit of the slit nozzle, a cleaning operation for removing the resist solidified material adhering to the slit inner wall of the slit nozzle has been performed manually. More specifically, a thin plate material made of metal or resin is inserted into the slit of the slit nozzle from the outside (nozzle discharge port side), and the thin plate material is slid in the longitudinal direction of the nozzle in the slit to scrape the solidified material. It was. However, as described above, the slit gap of this type of slit nozzle is usually as fine as 100 μm or less, and it is very troublesome and time-consuming to insert and clean a thin plate material therein. It has also become a factor of lowering the maintainability or operating rate of the coating apparatus. Furthermore, since the cleaning operation is inefficient and takes a long time, there is a problem that many particles are scattered around during the operation.

  The present invention solves the problems of the prior art as described above, and automatically and efficiently cleans the inside of the slit of the slit nozzle used in the spinless coating process while suppressing the generation of particles. Provided are a slit nozzle cleaning device and a spinless coating device that improve the quality, yield, and operation rate of a coating film by improving a maintenance function for a nozzle.

  In order to achieve the above object, a slit nozzle cleaning device according to a first aspect of the present invention is a slit nozzle cleaning device for cleaning the inside of a slit of a long slit nozzle used in a coating process, A thin plate-like scraping member that can be inserted and removed from the inside of the slit of the slit nozzle and the scraping member are held, the scraping member is inserted into the slit of the slit nozzle, and the solidified material is scraped into the slit. And a cleaning mechanism for moving the scraping member in a predetermined direction and extracting the scraping member from the slit.

  In the slit nozzle cleaning device configured as described above, work efficiency is improved by automating and standardizing the main work related to cleaning or cleaning of the slit nozzle in the slit, that is, the work of inserting and removing the scraping member from and into the slit nozzle. It is possible to suppress the generation of particles and significantly reduce the required time.

  A slit nozzle cleaning device according to a second aspect of the present invention is a slit nozzle cleaning device for cleaning the inside of a long slit nozzle used in a coating process, and is inserted into and removed from the slit of the slit nozzle from the outside. And a cleaning mechanism that holds the scraping member and moves the scraping member in a predetermined direction so as to scrape the solidified material in the slit.

  In the slit nozzle cleaning device configured as described above, the work efficiency is improved and particles are generated by automating and standardizing the scraping operation in the slit nozzle, which is one of the main tasks related to cleaning or cleaning the slit nozzle. Can be suppressed, and the required time can be shortened.

  A coating apparatus according to the present invention includes a slit nozzle that discharges a coating liquid onto a substrate to be processed during a coating process, a coating liquid supply unit that supplies the coating liquid to the slit nozzle during a coating process, and the substrate. A substrate support unit for supporting, and a scanning mechanism for performing relative movement in one horizontal direction between the slit nozzle and the substrate so that the slit nozzle performs coating scanning on the substrate during coating processing; And the slit nozzle cleaning device of the present invention for cleaning the inside of the slit of the slit nozzle between application processes.

  By providing the slit nozzle cleaning device of the present invention, the coating apparatus having the above configuration can improve the maintenance function for the slit nozzle 32 and improve the quality, yield, and operating rate of the resist coating film.

  According to the slit nozzle cleaning device or the coating device of the present invention, the configuration and operation as described above automatically and efficiently clean the inside of the slit of the slit nozzle used for the spinless coating process while suppressing the generation of particles. can do. In addition, the quality, yield, and operation rate of the coating film can be improved by improving the maintenance function for the slit nozzle.

It is a perspective view which shows one structural example of the resist coating device which can apply the slit nozzle cleaning apparatus of this invention. It is a partial cross section front view which shows the structure of the nozzle refresh part with which the said resist coating apparatus is equipped. It is a perspective view which shows the structure of the nozzle cleaning / cleaning part integrated in the said nozzle refresh part. It is a partial cross section side view which shows the structure of the slit nozzle cleaning apparatus in embodiment. It is sectional drawing which shows the structure of the scraper and holding | maintenance part which are contained in the said slit nozzle cleaning apparatus. It is a partial cross section side view which shows the structure in the scraper and holding | maintenance part contained in the said slit nozzle cleaning apparatus. It is a partial cross section front view which shows the state of each part in a holding | maintenance part when a scraper deform | transforms. It is a figure which shows the main structures of the said resist coating apparatus in a block format. It is a flowchart figure which shows the procedure of the whole operation | movement of the said slit nozzle cleaning apparatus. It is a figure which shows the scraper insertion operation | movement in the slit nozzle cleaning process in embodiment in steps. It is a flowchart figure which shows the procedure of the said scraper insertion operation | movement. It is a figure which shows the operation | movement of the corresponding | compatible process in case the said scraper insertion operation does not go well stepwise. It is a flowchart figure which shows the procedure of the scraping operation | movement in the slit nozzle cleaning process in embodiment. It is a disassembled perspective view which shows the mode of the said scraping operation | movement. It is a figure which shows an example of the operation | movement of 1 stroke in the said scraping operation | movement. It is a figure which shows an example of the return operation | movement when a catch generate | occur | produces in the said scraping operation | movement. It is a figure which shows the effect | action of the displacement determination part which uses an acceleration sensor in the said slit nozzle cleaning apparatus. It is a wave form diagram of each part which shows the effect | action of the displacement determination part using the said acceleration sensor. It is a figure which shows the shape of the suitable scraper in the said slit nozzle cleaning apparatus. It is sectional drawing which shows the structural example of the complete non-contact-type guide part in the said slit nozzle cleaning apparatus.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 shows a configuration example of a resist coating apparatus to which the slit nozzle cleaning apparatus of the present invention can be applied.

  The resist coating apparatus includes a levitation stage 10 that floats a substrate to be processed, such as a glass substrate G for FPD, in the air by gas pressure, and a substrate G that is floating in the air on the levitation stage 10. ), A slit nozzle 32 that supplies a resist solution to the upper surface of the substrate G that is transported on the floating stage 10, and a nozzle refresh unit 42 that refreshes the slit nozzle 32 between coating processes. Have.

  A number of gas injection holes 12 for injecting a predetermined gas (for example, air) upward are provided on the upper surface of the levitation stage 10, and the substrate G is placed on the upper surface of the stage by the pressure of the gas injected from the gas injection holes 12. It is configured to rise to a certain height.

  The substrate transport mechanism 20 includes a pair of guide rails 22A and 22B extending in the X direction across the levitation stage 10, a pair of sliders 24 that can reciprocate along the guide rails 22A and 22B, and the levitation stage 10. A substrate holding member (not shown) such as a suction pad provided on the slider 24 so as to detachably hold both side ends of the substrate G is provided. The slider 24 is moved by a linear movement mechanism (not shown). By moving in the transport direction (X direction), the substrate G is floated and transported on the floating stage 10.

  The resist nozzle 32 traverses the top of the levitation stage 10 in the horizontal direction (Y direction) orthogonal to the transport direction (X direction), and is slit-shaped with respect to the upper surface (surface to be processed) of the substrate G passing immediately below the resist nozzle 32. The resist solution R is discharged in a strip shape from the discharge port. The slit nozzle 32 is configured to be movable up and down so as to be movable in the vertical direction (Z direction) integrally with a nozzle support member 28 that supports the nozzle by a nozzle lifting mechanism 26 including a ball screw mechanism, a guide member, and the like. Yes. The slit nozzle 32 is connected via a resist supply pipe 30 to a resist supply unit 120 (FIG. 8) that includes a resist solution container and a liquid feed pump.

  A nozzle refresh unit 42 is provided above the levitation stage 10 adjacent to the slit nozzle 32. Details of the nozzle refresh unit 42 will be described later with reference to FIGS.

  Here, the resist coating operation in this resist coating apparatus will be described. First, a substrate G is carried into a carry-in area set on the front end side of the levitation stage 10 through a sorter mechanism (not shown) from a previous unit, for example, a thermal processing unit (not shown), and is waiting there. The slider 24 holds and receives the substrate G. On the levitation stage 10, the substrate G receives the pressure of gas (for example, high-pressure air) ejected from the gas ejection holes 12 and keeps the levitation state in a substantially horizontal posture.

  In this way, the substrate G moves in a horizontal posture at a constant speed in the transport direction (X direction), and at the same time, the slit nozzle 32 discharges the resist solution toward the substrate G directly below at a predetermined pressure or flow rate, A coating film of a resist solution having a uniform film thickness is formed from the front end side to the rear end side of the substrate G.

  When the rear end of the substrate G passes under the slit nozzle 32, a resist coating film is formed on the entire surface of the substrate. Subsequently, the substrate G is then levitated and conveyed on the levitating stage 10 by the slider 24, and a rear stage unit (not shown) from a carry-out area set at the rear end of the levitating stage 10 via a sorter mechanism (not shown). ).

  As shown in FIG. 2, the nozzle refresh unit 42 is a priming process in which a small amount of resist solution is discharged to the slit nozzle 32 and wound around the priming roller 46 as a preparation for the next coating process in one casing 44. The nozzle 48 for keeping the outlet 48 and the outlet of the slit nozzle 32 in an atmosphere of solvent vapor for the purpose of preventing drying, and for cleaning or washing the inside and outside of the slit nozzle 32 (particularly in the vicinity of the slit outlet). A nozzle cleaning / cleaning unit 52 is also provided.

  The slit nozzle 32 that has finished the coating process once (for one substrate) is first subjected to a cleaning process by the nozzle cleaning / cleaning unit 52, then waits in the nozzle bath 50, and immediately before the next coating process is started. The priming processing unit 48 receives a priming process.

  In order to place the slit nozzle 32 on each part (48, 50, 52) in the nozzle refresh unit 42, the entire nozzle refresh unit 42, that is, the casing 44 is moved in the substrate transport direction (X The slit nozzle 32 may be moved in the vertical direction (Z direction) by the nozzle lifting mechanism 26 (FIG. 1).

  As shown in FIG. 3, the nozzle cleaning / cleaning unit 52 includes an independent nozzle cleaning unit 56 and a nozzle cleaning unit 58, and these units 56, 58 are moved along the length of the slit nozzle 32 by a common Y-direction moving unit 60. It can move integrally in the direction (Y direction). The Y-direction moving unit 60 includes, for example, a rack and pinion mechanism, and includes a rack 62 that extends in the Y direction and a Y-direction carriage 64 that incorporates a gear (not shown) that rolls on the rack 62. .

The nozzle cleaning unit 58 supplies a cleaning liquid (for example, thinner) and a drying gas (for example, N ₂ gas) to the cleaning head 65 having a U-shaped cross section with an open top surface toward the lower end portion or the discharge port of the slit nozzle 32. A cleaning nozzle 66 and a gas nozzle (not shown) to be sprayed are mounted, and the cleaning liquid dropped upon hitting the slit nozzle 32 is collected by the drain port 68 and dropped or collected by vacuum.

  The slit nozzle cleaning device 70 in this embodiment includes a nozzle cleaning unit 56 incorporated in the priming processing unit 42 and an X direction for moving the entire priming processing unit 42 (casing 44) in the substrate transport direction (X direction). The moving part 54 and a Y-direction moving part 60 for moving the entire nozzle cleaning unit 56 in the casing 44 in the nozzle longitudinal direction (Y direction) are configured.

  As shown in FIG. 4, the nozzle cleaning unit 56 includes a U-shaped support body or main frame 72 that is integrally coupled to the Y-direction carriage 64 of the Y-direction moving unit 60, and the slit 32 a of the slit nozzle 32. A thin scraper (scraping member) 74 that can be inserted and removed from (discharge port side), a holding portion 76 that holds the base end portion of the scraper 74, and the scraper 74 integrally with the holding portion 76 in the vertical direction, that is, the slit nozzle 32. And a lifting mechanism 78 for moving in the discharge direction, and a turning mechanism 82 for turning the scraper 74 around the pivot 80 provided in the holding portion 76.

  More specifically, the elevating mechanism 78 is coupled to the elevating drive unit 84 fixed to the bottom of the main frame 72 and the elevating drive shaft 84 a of the elevating drive unit 84 and attached to the inner side surface of the main frame 72. An elevating frame 88 having an L-shaped cross section is engaged with a vertical guide rail 86 so as to be movable up and down. The elevating drive unit 84 may use an air cylinder, but may preferably be composed of a servo motor and a rotation / straight-ahead conversion mechanism in view of response speed and position accuracy.

  The turning mechanism 82 includes a motor 90 mounted horizontally on a lifting frame 88 via a support member, a rotation drive shaft 92 that connects the output shaft of the motor 90 and the holding portion 76, and a lifting support body 88. And a bearing 94 that supports the rotary drive shaft 92. A rotary drive shaft 92 forms the pivot shaft 80.

  As shown in FIGS. 5 and 6, the holding portion 76 includes an upper support block 96 that holds the base end portion of the scraper 74 in a housing 94 having an upper surface opening for passing the scraper 74, and a housing. The upper support block 96 and the lower support block 100 that support the scraper 74 are provided via an elastic member 98 such as a coil spring or rubber.

  The upper support block 96 clamps and fixes the scraper 74 by tightening a pair of half-divided blocks 96a and 96b sandwiching the scraper 74 from both sides in a sandwich shape with the bolts 102. In this embodiment, a coil spring 104 is provided between the movable block 96 and the inner wall of the housing 94 for increasing the elastic drag against the external force in the turning direction of the scraper 74.

  The scraper 74 is supported in a state of standing vertically with respect to the holding portion 76 (reference posture) when no external force is applied. However, when an external force is applied, particularly when an external force F having a lateral component parallel to the plate surface of the scraper 74 is applied to the upper or middle portion of the scraper 74, as shown in FIG. 74 and the upper support block 96 are displaced (tilted) in the turning direction against the coil springs 98 and 104.

  In this embodiment, in order to determine whether or not the displacement of the scraper 74 with respect to the holding unit 76, particularly the above-described turning displacement exceeds a certain reference value, the optical first displacement determination unit 106 and the acceleration sensor And a second displacement determination unit 108 using.

  The first displacement determination unit 106 is mounted on the holding unit 76 so as to face the scraper 74 directly in front, and the light receiving unit mounted on the holding unit 76 behind or behind the scraper 74 when viewed from the light projecting unit 110. Part 112. The light projecting unit 110 includes a light emitting element such as a light emitting diode, and the light receiving unit 112 includes a photoelectric conversion element such as a photodiode, and an optical fiber type optical sensor can be suitably used.

  An opening 74 a is formed in the vicinity of a portion of the scraper 74 that faces the light projecting unit 110 and the light receiving unit 112. When the scraper 74 stands upright in the reference posture (FIG. 6), the light projecting unit 110 and the light receiving unit 112 face each other through the opening 74a. At this time, the light beam LB emitted or projected from the light projecting unit 110 passes through the opening 74a of the scraper 74 and reaches the light receiving unit 112, and the electrical signal output from the light receiving unit 112 receives the light beam LB. It shows that.

  When the scraper 74 turns and receives an external force and the displacement exceeds a reference value (FIG. 7), the light beam LB projected from the light projecting unit 108 deviates from the opening 74a of the scraper 74 and moves to the scraper 74. It hits the plate surface and does not reach the light receiving unit 110. At this time, the light receiving unit 110 outputs an electrical signal indicating that the light beam LB is not received. Note that the reference value of the turning displacement can be adjusted by the lateral size of the opening 74a.

  The second displacement determination unit 108 has acceleration sensors 114 and 116 attached to the upper support block 96 and the lower support block 100, respectively. The operation of these acceleration sensors 114 and 116 will be described later with reference to FIG.

  Referring again to FIG. 4, the upper plate-like horizontal support portion of the main frame 72 is formed with a slit opening 72 a that allows the scraper 74 to pass up and down at a position directly above the holding portion 76. A guide 118 is attached. The guide portion 118 has a slit-like cavity 118 a that narrows toward the discharge port of the upper slit nozzle 32 at a position overlapping the slit opening 72 a of the main frame 72.

  In the nozzle cleaning unit 56, when the inside of the slit 32a of the slit nozzle 32 is cleaned, as shown in FIG. 4, the guide portion 118 engages the upper surface thereof with the vicinity of the discharge port of the slit nozzle 32 or the lower end portion of the lip. To be positioned. In this state, the scraper 74 is inserted from the bottom through the slit-shaped cavity 118a of the guide 118 and into the interior of the discharge port of the slit nozzle 32 or into the slit 32a.

The slit nozzle 32 includes a front lip 33A and a rear lip 33B extending in parallel with the longitudinal direction of the nozzle. The lips 33A and 33B are abutted with a shim 35 interposed therebetween and are integrally coupled with a bolt (not shown). A buffer portion or a manifold portion 32b connected to the upper end of the slit 32a is formed at the center portion in the slit nozzle 32. A resist introduction port 32c is provided at the center of the slit nozzle 32 in the longitudinal direction of the nozzle, and the resist introduction port 32c and the manifold portion 32b are connected by a resist introduction passage 32d. A resist supply pipe 30 from the resist supply unit 120 (FIG. 8) is connected to the resist introduction port 32c.
It is.

  FIG. 8 is a block diagram showing the main configuration around the slit nozzle 32 in the resist coating apparatus of this embodiment. The main control unit 122 performs overall control of the entire resist coating apparatus. The above-described levitation stage (18, 28, 18 ′), substrate transport mechanism (20, 30, 20 ′), nozzle lifting mechanism 26, slit nozzle cleaning device 70, resist supply unit 120, etc. are all controlled by the main control unit 122. Works below.

  The slit nozzle cleaning device 70 includes a nozzle cleaning control unit 124 as a local controller. The nozzle cleaning control unit 124 exchanges control signals with the main control unit 122, and in response to commands from the main control unit 122, each unit in the slit nozzle cleaning device 70, particularly the X-direction moving mechanism 54 and the Y-direction moving mechanism described above. 60, the operation of the lifting mechanism 78 and the turning mechanism 80 is controlled. Output signals from the first and second displacement determination units 106 and 108 are given to the nozzle cleaning control unit 124.

  A switching valve 126 is provided in the middle of the resist supply pipe 30. This switching valve 126 is also connected to a cleaning liquid supply pipe 130 from the cleaning liquid supply unit 128, and a position where the resist liquid from the resist supply unit 120 is supplied to the slit nozzle 32, and from the cleaning liquid supply unit 128. It is possible to switch between the position for supplying the cleaning liquid (thinner).

  At both ends in the longitudinal direction of the slit nozzle 32, vents 32e communicating with the manifold 32b are provided. These vents 32e are connected to a drainage pipe 132 leading to a drain tank (not shown). An opening / closing valve 134 is provided in the middle of the drainage pipe 132.

  Next, the operation of the slit nozzle cleaning device 70 will be described with reference to FIGS. All operations of the slit nozzle cleaning device 70 are performed under the control of the main control unit 122 and the nozzle cleaning control unit 124.

  FIG. 9 shows the overall operation of the slit nozzle cleaning process in the slit nozzle cleaning device 70. This slit nozzle cleaning process may be performed periodically, for example, in units of one lot or several lots between resist coating processes.

In the initial initialization (step S ₁ ), the resist solution remaining in the slit nozzle 32 is replaced with a cleaning solution (thinner solution). In this liquid replacement, the cleaning liquid is fed into the slit nozzle 32 from the cleaning liquid supply unit 128 through the cleaning liquid supply pipe 130, the switching valve 126, and the resist supply pipe 30, and the drain pipe 132 and the ON state from the vent 32e of the slit nozzle 32. Most of the resist solution is discharged to the drain tank through the open / close valve 134. A part of the resist solution is discharged from the discharge port of the slit nozzle 32.

In the initialization (step S ₁ ), as shown in FIG. 10A, alignment (positioning) of the scraper 74 and the holding unit 76 with respect to the slit nozzle 32 is also performed. For this alignment, not only the moving mechanism 54, 60, 78, 80 on the slit nozzle cleaning device 70 side but also the nozzle lifting mechanism 26 is used.

Next, the operation of inserting the scraper 74 into the slit 32a of the slit nozzle 32 (step S ₂₎ is performed. In a preferred embodiment, as shown in FIG. 10, this scraper insertion operation is divided into three stages: a first scraper swivel movement (b), a scraper lift movement (c), and a second scraper swivel movement (d). Done.

FIG. 11 shows the procedure of the scraper insertion operation. The first scraper swivel movement (b) is performed in the procedure of steps S _{10 to} S ₁₄ , the scraper up / down movement (c) is performed in the procedure of steps S _{15 to} S ₁₈ , and the second scraper swivel movement (d) is performed in step It is carried out in the procedure of S ₁₉ ~S _23.

In the first scraper turning movement (b), an operation of turning the scraper 74 by a predetermined stroke (rotation angle) integrally with the holding portion 76 is executed (step S ₁₂ ). When the turning movement is performed smoothly, the deformation of the scraper 74 during the operation, that is, the relative turning displacement of the scraper 74 with respect to the holding unit 76 is almost zero or very small. , the determination result is issued (step S ₁₃₎ without substantial displacement than 108 (no snagging), in this case moves to the next scraper lifting movement (c).

However, when the tip of the scraper 74 hits something in the vicinity of the discharge port of the slit nozzle 32 and does not enter, the scraper 74 is deformed (swivel displacement relative to the holding unit 76), and the amount of deformation When the value exceeds the reference value, the displacement determination units 106 and 108 output a determination result indicating that there is substantial displacement (there is a catch) (step S ₁₃ ). At this time, as shown in FIG. 12, the scraper 74 and the holding unit 76 are returned to their original positions immediately before the turning operation (step S ₁₄ ), and the turning movement operation is retried (step S ₁₄ ). If the number of retries reaches the set number (i _s ), the current slit nozzle cleaning process is stopped at this stage, and an alarm indicating that cleaning is not possible is issued through a buzzer or a display (step S ₁₀ → S _{11 → S 15 → S 6)} .

The scraper raising / lowering movement (c) is an operation of moving the scraper 74 up and down by a predetermined stroke (distance) integrally with the holding portion 76 (step S ₁₈ ). In this operation, when the tip of the scraper 74 is caught by the solidified material or foreign matter in the slit nozzle 32, a determination result indicating that there is a substantial displacement (there is a catch) is output from the displacement determination units 106 and 108 as described above. (step S _19). If the number of retries (step S ₂₀ ) reaches the set number (j _s ), the current slit nozzle cleaning process is stopped at this stage, and an alarm indicating that cleaning is not possible is issued (step S ₁₆ → S _{17 → S 21 → S 6)} .

In the second scraper turning movement (d), the scraper 74 is turned by a predetermined stroke (rotation angle) integrally with the holding portion 76 in order to set the posture of the scraper 74 in the slit nozzle 32 to an initial state, for example, an upright posture. (step S _24). Even in this turning operation, when the tip of the scraper 74 is caught by the solidified material or foreign matter in the slit nozzle 32, a determination result indicating that there is substantial displacement (with catch) is output from the displacement determination units 106 and 108 as described above. (step S _25). When the number of retries (step S ₂₆ ) reaches the set number (m _s ), the current slit nozzle cleaning process is stopped at this stage, and an alarm indicating that cleaning is not possible is issued (step S ₂₂ → S _{23 → S 27 → S 6)} .

  Note that the turning mechanism 80 is mainly used for the first and second scraper turning movements (b) and (d), and the raising / lowering mechanism 78 is mainly used for the scraper raising / lowering movement (c). In any case, it is preferable to insert the scraper 74 until the tip of the scraper 74 reaches the vicinity of the lower end of the manifold 32b in the slit nozzle 32.

  The above three-stage scraper insertion operations (a), (b), and (c) are merely examples, and various modifications can be made to the scraper insertion operation according to the present invention. For example, without using the turning mechanism 80, a scraper insertion operation combining a vertical movement and a Y-direction movement or a scraper insertion operation only for the vertical movement is possible.

When the above-described scraper insertion operation is successfully completed, an operation (step S ₃ ) is performed to drive the scraper 74 in a predetermined direction in order to scrape the resist solidified material and other foreign matters in the slit nozzle 32. . FIG. 13 shows the procedure of this scraping operation. As shown in FIG. 14, this scraping operation is based on an operation of moving the scraper 74 in the longitudinal direction of the nozzle (Y direction) integrally with the holding portion 76, and this is combined with a swiveling operation or an elevating operation with a constant cycle. One-stroke or one-pitch scraper driving is repeated from the end point on one end of the nozzle to the end point on the other end of the nozzle (steps S ₃₀ → S ₃₁ → S ₃₂ → S ₃₃ → S ₃₀ →...). Before starting the scraping operation, the slit lifting nozzle 38 raises the slit nozzle 32 somewhat to separate the guide 118 from the slit nozzle 32.

During the scraping operation, when the scraper 74 is caught in the solidified material or other foreign matter in the slit nozzle 32 and is greatly deformed, a judgment result indicating that there is substantial displacement (with catching) is output from the displacement judgment units 106 and 108 (step) S ₃₁ ), for example, as shown in FIGS. 15A and 15B, the scraper 74 is retracted in a reverse operation to rewind to the original position before one stroke (one pitch) (step S ₃₆ ), and then retry or restart. (step S _30). Also in this case, when the number of retries or retreats (step S ₂₆ ) reaches the set number (n _s ), the current slit nozzle cleaning process is stopped at this stage, and an alarm indicating that cleaning is impossible is issued (step S ₂₆ ). _{S 34 → S 35 → S 37} → S 6).

  Here, the operation of the second displacement determination unit 108 will be described with reference to FIGS. 16 and 17. In FIG. 16, a comparator 140 compares the outputs of both acceleration sensors 114 and 116, and outputs a signal representing the difference E. The determination circuit outputs a determination signal MS indicating the magnitude relationship between the difference E from the comparator 140 and the predetermined reference value TH. That is, L level MS is output when E <TH, and H level MS is output when E> TH. This determination signal MS is given to the nozzle cleaning control unit 124 (FIG. 8).

  For example, in the scraping operation as described above, the scraper 74 and the holding unit 76 move in the Y direction with a trapezoidal waveform velocity characteristic V as shown in FIG. At this time, the same acceleration as that applied to the scraper 74 is applied to the acceleration sensor 114 attached to the upper support block 96, and the acceleration sensor 116 attached to the lower support block 100 is attached to the housing 94 of the holding portion 76. The same acceleration is applied.

  Therefore, if the scraper 74 is not caught during the scraping operation, there is almost no substantial deformation or displacement of the scraper 74, the output waveforms of both acceleration sensors 114 and 116 are substantially the same, and the difference E is substantially zero. Signal MS is at L level.

  However, if the scraper 74 is caught by a solidified material or foreign matter during the scraping operation and deformed, a negative acceleration component G appears in the output of the acceleration sensor 114, and the difference E is not zero. When the difference E is large enough to exceed the reference value TH, the determination signal MS is at the H level (there is a catch).

When the scraping operation as described above is successfully completed, an operation (step S ₄ ) for removing the scraper 74 from the slit nozzle 32 is performed next. In this extraction operation, the scraper 74 is lowered integrally with the holding portion 76 by the lifting mechanism 78.

 After the scraping operation is completed, the switching valve 126 in FIG. 8 is switched to the cleaning liquid supply unit 128 side to supply the cleaning liquid to the slit nozzle 32. At the same time, the on-off valve 134 is opened, and most of the cleaning liquid is scraped off by flowing through the route of the resist inlet 32c of the slit nozzle 32 → the resist inlet passage 32d → the manifold portion 32b → the vent portion 32e → the drain pipe 132. Drain the kimono to the drain. As described above, by discharging the cleaning liquid to the drain simultaneously with the scraping operation, it is possible to improve the discharging performance of the fixed object.

Upon completion of the sampling operation, as a post-processing operation to replace the cleaning liquid in the slit nozzle 32 to resist liquid (Step S ₅₎ is performed. In this liquid replacement, the switching valve 126 is switched to the resist solution supply unit 120 side, the resist solution is sent from the resist solution supply unit 120 into the slit nozzle 32, and the drain pipe 132 and the ON state are opened from the vent 32e of the slit nozzle 32. Most of the cleaning liquid is discharged to the drain tank through the open / close valve 134. A part of the cleaning liquid is discharged from the nozzle discharge port.

  The material of the scraper 74 used in this embodiment is preferably one having appropriate hardness and elasticity, and for example, copper or resin can be suitably used. Also, the shape of the scraper 74 is arbitrary. For example, as shown in FIG. 18, a scraper shape (74B, 74C) in which the side part used for scraping is slanted, a scraper shape with a saw blade (74A), etc. Is possible.

Further, the guide portion 118 used in the scraper insertion operation (step S ₂ ) can be transformed into a completely non-contact type as shown in FIG. This completely non-contact type guide portion 118 is used to guide and guide the tip end portion of the scraper 74 by a pair of curved plates 150 which are provided in the main frame 72 through a rotating shaft 146 and a coil spring 148 so as to be elastically displaceable. A slit-like cavity 150 that narrows toward the discharge port of the slit nozzle 32 is formed.

When the scraper 74 is returned to the original position in the retry of the scraper insertion operation (step S ₂ ) (step S ₁₄ ), the positions of the scraper 74 and the holding unit 76 may be finely adjusted in the X direction.

It is also possible to use a camera (not shown) for the scraper insertion operation (step S ₂ ). In other words, the scraper 74 may be successfully inserted while monitoring or analyzing the image of the periphery of the tip of the scraper 74 when inserted into the discharge port of the slit nozzle 32 with a camera.

  As described above, the slit nozzle cleaning device 70 of this embodiment eliminates the need for any manual work, and automates / stylizes the cleaning or cleaning work in the slit of the slit nozzle 32 to improve work efficiency, Suppressing the occurrence and significantly shortening the required time.

  Further, the resist coating apparatus of this embodiment includes the slit nozzle cleaning device 70, thereby improving the maintenance function for the slit nozzle 32 and improving the quality, yield, and operating rate of the resist coating film.

  As a modification of the above embodiment, a part of the function of the slit nozzle cleaning device 70 can be replaced manually. In particular, the operation of inserting the scraper 74 into the slit nozzle 32 and the operation of extracting the scraper 74 from the slit nozzle 32 can be performed manually. In this case, the slit nozzle cleaning device 70 may be specialized for the scraping function. Therefore, the device configuration can be simplified.

  Moreover, in the said embodiment, in order to determine whether the reference value with which the displacement of the scraper 74 with respect to the holding | maintenance part 76 was exceeded was exceeded, the optical 1st displacement determination part 106 and the 2nd displacement determination part which used an acceleration sensor 108 was used in combination. However, either one of the displacement determination units may be used or installed, and the other displacement determination unit may be omitted.

  The present invention is not limited to the slit nozzle used in the substrate floating method or the spinless type coating process as in the above embodiment, and can be a slit nozzle used in any coating process or liquid process.

  As the coating solution in the present invention, in addition to the resist solution, for example, a coating solution such as an interlayer insulating material, a dielectric material, and a wiring material can be used, and various chemical solutions, developing solutions, rinse solutions, and the like are also possible. The substrate to be processed in the present invention is not limited to an LCD substrate, and other flat panel display substrates, semiconductor wafers, CD substrates, photomasks, printed substrates and the like are also possible.

10 Floating stage 20 Substrate transport mechanism
26 Nozzle Lifting Mechanism 30 Resist Supply Pipe 32 Slit Nozzle 58 Nozzle Cleaning Unit 70 Slit Nozzle Cleaning Device 74 Scraper 76 Holding Unit

Claims (23)

A slit nozzle cleaning device for cleaning the inside of a slit of a long slit nozzle used in a coating process,
A thin plate-shaped scraping member that can be inserted and removed from the inside of the slit of the slit nozzle;
Holding the scraping member, inserting the scraping member into the slit of the slit nozzle, moving the scraping member in a predetermined direction so as to scrape the solidified material in the slit, and then scraping the scraping member from the slit. A slit nozzle cleaning device comprising: a cleaning mechanism for extracting a member. The cleaning mechanism is
A holding portion for holding a proximal end portion of the scraping member;
A first moving mechanism for moving the scraping member integrally with the holding portion in the discharge direction of the slit nozzle;
A second moving mechanism for moving the scraping member integrally with the holding portion in the longitudinal direction of the slit nozzle;
Performing the operation of inserting the scraping member into the slit of the slit nozzle using the first moving mechanism;
Performing scraping operation in the slit of the slit nozzle using the second moving mechanism,
Performing the operation of removing the scraping member from the slit of the slit nozzle using the first moving mechanism;
The slit nozzle cleaning device according to claim 1.   The slit nozzle cleaning device according to claim 2, wherein the cleaning mechanism also uses the second moving mechanism for the operation of inserting the scraping member into the slit of the slit nozzle.   4. The slit nozzle cleaning device according to claim 2, wherein the cleaning mechanism also uses the first moving mechanism for a scraping operation in the slit of the slit nozzle. 5. The cleaning mechanism is
A third moving mechanism for rotating the scraping member around a pivot provided in the holding portion;
The third moving mechanism is also used for the operation of inserting the scraping member into the slit of the slit nozzle.
The slit nozzle cleaning apparatus as described in any one of Claims 2-4. The cleaning mechanism is
A third moving mechanism for rotating the scraping member around a pivot provided in the holding portion;
The third moving mechanism is also used for the scraping operation in the slit of the slit nozzle.
The slit nozzle cleaning apparatus as described in any one of Claims 2-4. The cleaning mechanism is
A fourth moving mechanism for moving the scraping member integrally with the holding portion in one horizontal direction perpendicular to the longitudinal direction of the slit nozzle;
The fourth moving mechanism is also used for the operation of inserting the scraping member into the slit of the slit nozzle.
The slit nozzle cleaning apparatus as described in any one of Claims 2-6.   The said cleaning mechanism has a guide part for guiding the front-end | tip part of the said scraping member in the said slit, when inserting the said scraping member in the slit of the said slit nozzle, The any one of Claims 2-7 The slit nozzle cleaning device according to item.   The guide portion has a slit-like cavity that narrows toward the discharge port of the slit nozzle so as to guide and pass the tip of the scraping member, and is positioned in contact with the slit nozzle. The slit nozzle cleaning device according to claim 8.   The guide portion has a slit-like cavity that narrows toward the discharge port of the slit nozzle so as to guide and pass the tip of the scraping member, and is positioned without contact with the slit nozzle. The slit nozzle cleaning device according to claim 8.   The slit nozzle cleaning device according to any one of claims 2 to 10, wherein the holding unit includes an elastic member that can elastically displace the scraping member.   The slit nozzle cleaning according to claim 11, wherein the cleaning mechanism includes a displacement determination unit that detects a relative displacement of the scraping member with respect to the holding unit and determines whether or not the displacement amount exceeds a reference value. apparatus.   When the cleaning mechanism inserts the scraping member into the slit of the slit nozzle, the insertion of the scraping member is confirmed based on the determination result obtained from the displacement determination unit or the scraping member is inserted. The slit nozzle cleaning device according to claim 12, which is retried.   The cleaning mechanism monitors whether the scraping operation is normally performed based on a determination result obtained from the displacement determination unit when performing the scraping operation in the slit of the slit nozzle. Item 14. The slit nozzle cleaning device according to Item 12 or Item 13.   The slit nozzle cleaning device according to claim 14, wherein the cleaning mechanism monitors whether or not the scraping operation is normally performed every time the scraping member moves a certain distance in the longitudinal direction of the slit nozzle. .   The slit nozzle cleaning device according to claim 15, wherein when the scraping operation is not performed normally, the cleaning mechanism returns the scraping member in a reverse direction by a predetermined distance and then restarts the scraping operation. The displacement determination unit
A light projecting unit provided in the holding unit so as to project a light beam toward the scraping member or the vicinity thereof;
When the light beam emitted from the light projecting unit passes through a predetermined hole formed in the scraping member or passes near the scraping member, the light beam is received and photoelectrically converted. And a light receiving portion provided in the
The slit nozzle cleaning device according to any one of claims 12 to 16, wherein it is determined whether or not the displacement exceeds a reference value based on an output of the light receiving unit. The displacement determination unit
A first acceleration sensor attached to the holding portion independently of the displacement of the scraping member;
A second acceleration sensor attached to the holding portion so as to be displaced according to the displacement of the scraping member;
The difference between the output signal of the first acceleration sensor and the output signal of the second acceleration sensor is taken, and whether or not the displacement exceeds the reference value depending on whether or not the difference is larger than the reference value. The slit nozzle cleaning apparatus as described in any one of Claims 12-16 which determines. A slit nozzle cleaning device for cleaning the inside of a slit of a long slit nozzle used in a coating process,
A thin plate-shaped scraping member that can be inserted and removed from the inside of the slit of the slit nozzle;
A slit nozzle cleaning device, comprising: a cleaning mechanism that holds the scraping member and moves the scraping member in a predetermined direction so as to scrape the solidified material in the slit. The cleaning mechanism is
A holding portion for holding a proximal end portion of the scraping member;
A first moving mechanism for moving the scraping member integrally with the holding portion in the longitudinal direction of the slit nozzle;
Performing the operation of inserting the scraping member into the slit of the slit nozzle using the first moving mechanism;
The slit nozzle cleaning device according to claim 19. The cleaning mechanism is
A second moving mechanism for rotating the scraping member around a pivot provided in the holding portion;
The second moving mechanism is also used for the scraping operation in the slit of the slit nozzle.
The slit nozzle cleaning apparatus of Claim 19 or Claim 20. The cleaning mechanism is
A third moving mechanism for moving the scraping member integrally with the holding portion in the discharge direction of the slit nozzle;
The third moving mechanism is also used for the scraping operation in the slit of the slit nozzle.
The slit nozzle cleaning apparatus as described in any one of Claims 19-21. A slit nozzle that discharges the coating liquid in a strip shape to the substrate to be processed during the coating process;
A coating solution supply unit for supplying a coating solution to the slit nozzle during the coating process;
A substrate support for supporting the substrate;
A scanning mechanism that performs relative movement in one horizontal direction between the slit nozzle and the substrate so that the slit nozzle performs application scanning on the substrate during a coating process;
The coating apparatus which has a slit nozzle cleaning apparatus as described in any one of Claims 1-22 for cleaning the inside of the slit of the said slit nozzle between application | coating processes.

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