JP5656711B2 - Coating device - Google Patents

Description

  The present invention relates to a coating apparatus that supplies a coating liquid to a substrate and forms a thin film on the substrate.

  As an example of an apparatus that performs processing on a substrate, a slit nozzle type coating apparatus that forms a thin film by applying a coating liquid by discharging it from a slit nozzle that moves relative to the substrate has been known for a long time. This coating apparatus is used in many fields including flat panel displays such as liquid crystal. In this coating apparatus, it is necessary to form a bead of the coating liquid between the slit nozzle and the substrate in order to continuously discharge the coating liquid from the slit nozzle during the movement, while moving the substrate and the slit nozzle relatively. In order to maintain the bead, it is necessary to set the distance between the substrate and the slit nozzle as narrow as about 100 to 200 μm, for example.

  However, foreign substances such as particles are not completely removed although the substrate before coating is cleaned. If coating is performed in the presence of foreign matter, the slit nozzle collides with the foreign matter or the substrate due to the foreign matter itself or the penetration of the foreign matter under the substrate, damaging the substrate or the slit nozzle or interrupting the supply of the coating liquid. Problems occur. In order to prevent this, as in Patent Document 1, a technique for detecting foreign matter by various means including laser light before coating has been proposed.

  This foreign matter detection technology, particularly the technology using laser light among them, is effective in detection accuracy, but if the optical axis is shifted even a little, foreign matter cannot be detected. In recent years, the substrate size has increased due to an increase in large liquid crystal TVs, and those with a coating width exceeding 2 m have become mainstream, and the optical axis adjustment accuracy of the sensor has become severe. Further, for shortening the tact time, the acceleration at the start of coating, the coating speed, and the deceleration at the end of coating are increased, and the force applied to the foreign matter detection device attached to the coating device is also increased. Therefore, it is necessary to fix the foreign object detector so that the optical axis is not shifted after the optical axis adjustment.

  For fixing the foreign object detector, a method is used in which an L-shaped bracket (displacement restricting member) to which the laser sensor is fixed is fixed with a bolt to a tap provided on the coating device side after adjusting the optical axis of the foreign object detector. ing. However, according to this method, when the bolt is tightened for fixing the L-shaped bracket, the L-shaped bracket is pulled in the tightening rotation direction of the bolt, and the posture of the L-shaped bracket is shifted in the rotational direction. As a result, there is a problem that the optical axis of the sensor fixed to the L-shaped bracket is displaced.

Japanese Patent No. 4325084

  The present invention overcomes the above problems and provides a method for fixing a sensor without causing an optical axis shift of the sensor.

In order to solve the above problems, the coating apparatus of the present invention scans the substrate by moving relative to the sheet-like substrate, and forms a predetermined layer on the substrate surface by discharging the treatment liquid onto the substrate surface. A coating apparatus having at least a foreign matter detection device that is disposed upstream of the ejection device in the scanning direction and detects foreign matter on a substrate, wherein the foreign matter detection device has a laser beam parallel to the substrate surface. A light projecting device that irradiates; a light receiving device that receives the projected laser light; a fixing member that supports the light projecting device and the light receiving device so as to adjust an optical axis; and a light projecting device and a light receiving device, respectively. A displacement regulating member that abuts on the fixing member and regulates the displacement of the light projecting device and the light receiving device, and the displacement regulating member has a sheet-like elasticity on a surface that abuts on the light projecting device or the light receiving device. Prepare body And, the displacement regulating member, the fixing member is separable freely held to, wherein the displacement-regulating members, the actuating member to be projectable is provided on the stationary member side, the displacement by the actuating member It is characterized in that the regulating member is brought into and out of contact with the fixed member .

  It is possible to provide a coating apparatus capable of performing a stable coating operation without causing damage to the slit nozzle and the substrate due to the foreign matter, by the coating device having the foreign matter detection device of the present invention, which can suppress the optical axis deviation of the foreign matter detection device. I can do it.

It is a perspective view of the coating device of this invention. It is explanatory drawing which shows the relationship between a foreign material and a slit nozzle. It is a front view which shows a foreign material detection apparatus. It is a side view of the projector of a foreign material detection apparatus.

  An embodiment according to the coating apparatus of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing an outline of an embodiment of a coating apparatus having a foreign matter detection apparatus of the present invention. In FIG. 1, the coating apparatus 1 includes a machine base 11, a stage 21 that fixes the substrate 10, a discharge device 30 that discharges the coating liquid and applies the coating liquid to the substrate 10, and a foreign matter detection device 40.

  In the present embodiment, the coating liquid is applied onto the substrate while the ejection device 30 performs scanning on the substrate 10, and the scanning direction is the X direction (also referred to as the application direction), and is orthogonal to the horizontal plane. The direction to be performed is the Y-axis direction, the direction orthogonal to both the X-axis and the Y-axis directions is the Z-axis direction, and the description will be further made with the right direction as the downstream side and the left direction as the upstream side in FIG.

  The machine base 11 and the stage 21 are made of stone, ceramic, or metal structure. The substrate 10 is a thin plate made of glass or the like, and is carried into the stage 21 by a carrying-in device (not shown) such as a robot. At that time, lift pins (not shown) are incorporated in the stage 21 in order to receive the substrate 10 carried from the carry-in device.

  When the carry-in apparatus transfers the substrate 10 to the lift pins, the lift pins are lowered to place the substrate 10 on the stage 21. The stage 21 is further provided with a substrate positioning mechanism (not shown), and performs positioning of the substrate 10 installed on the stage 21 in the X and Y directions.

  A plurality of suction holes (not shown) are formed in the stage 21, and the substrate 10 positioned by the positioning mechanism by vacuum suction of the substrate 10 through a vacuum pump (not shown) is placed on the stage 21. Fix it. The discharge device 30 is a device for applying a coating liquid to the substrate 10 in a portal shape, and includes a slit nozzle 31 that discharges the coating liquid, a side plate 32 that supports the portal structure, a stay 33 that supports the slit nozzle 31, and a slit nozzle. The ascending mechanism 34 is configured.

  The slit nozzle 31 has a slit-like discharge port, and discharges the coating liquid from the discharge port to the substrate 10 while scanning the substrate 10 in the X direction in accordance with the movement of the discharge device 30 in the X direction. The slit nozzle 31 has a stay 33 attached to an upper portion thereof for improving straightness and operability. The slit nozzle 31 moves in the Z direction between the application position and the standby position, and the movement is performed by the slit nozzle raising mechanism 34. The slit nozzle raising mechanism 34 is composed of a combination of driving means such as a motor and linear motion means, or linear driving means such as a linear motor. A coating liquid replenishing mechanism 51 for replenishing the coating liquid is connected to the slit nozzle 31 by a pipe 53. The coating solution supply mechanism 51 includes a coating solution supply tank 55, a buffer tank 52, a control valve 53, a pipe 54, and a coating solution supply tank 55. The coating solution stored in the coating solution supply tank 55 is sent to the buffer tank 52 by means such as compressed air and temporarily stored. Next, the control valve 53 opens and closes according to a signal output from a control unit (not shown) of the coating apparatus 1 according to the coating state, and sends the liquid to the coating liquid supply tank 55. The coating liquid supply tank 55 sends the coating liquid for one substrate to the slit nozzle 31 in accordance with the coating operation.

  FIG. 2 is a schematic explanatory diagram showing the relationship between the slit nozzle and the foreign matter. The discharge device 30 performs a linear motion by a drive device (not shown) such as a linear motor, and discharges the coating liquid from the slit nozzle 31 while moving on the substrate 10 in the X direction. At that time, the distance between the front end of the slit nozzle 31, that is, the front end from which the coating liquid is discharged, and the substrate 10 is set to about 100 μm. Therefore, when the foreign material 49a is present on the substrate 10 as shown in FIG. 2 or when the foreign material 49b has entered the lower side of the substrate 10, the ejection device 30 performs scanning as described above. The tip of the nozzle 31 may come into contact with the substrate 10 that has risen due to the foreign matter 49a itself or the foreign matter 49b sinking, and may be bitten in the worst case. Such biting may cause damage to not only the substrate 10 but also the slit nozzle 31 depending on the type of foreign matter.

  In order to prevent this biting, the foreign object detector 40 is installed, but there is a technical problem with foreign object detection using laser light as described above. Therefore, the foreign object detection device 40 of the present invention will be described in detail below with reference to FIGS.

  As shown in FIG. 3, the foreign object detection device 40 includes a light projector 43 a (light projector), a light receiver 43 b (light receiver), a control device 41, and a control / power wiring 42. The projector 43a is composed of a laser oscillator and an irradiation optical system. The laser light (class 2) having an output of 0.7 mW and a wavelength of 670 nm is adjusted to approximately parallel light by the irradiation optical system and is projected in the direction of the optical axis 50. The light receiver 43b has a photodiode and receives the laser light projected from the projector 43a. Here, when there is the foreign object 49, all or a part of the projected laser beam hits the foreign object 49 and is reflected or scattered. As a result, the laser beam received by the light receiver 43b is reduced compared to the case where there is no foreign object 49. The control device 41 compares the received light signal transmitted from the light receiver 43b via the control / power wiring 42 and transmits it to the control device (not shown) of the coating device 1 as foreign matter information, whereby the coating device 1 determines whether there is a foreign matter. It can be judged. The control / power wiring 42 is composed of a plurality of harnesses, and is used for transmitting and receiving the power and drive signals of the projector and the light receiver in addition to the signals.

  FIG. 4 is a diagram showing a detailed configuration of the foreign object detection device 40. The foreign object detection device 40 is divided into a light projecting side and a light receiving side, but the difference is only in the difference between the light projecting device and the light receiving device. Accordingly, only the light projecting side is shown in FIG. 4, but the same description can be obtained for the light receiving side by replacing the light projecting device 43a with the light receiving device 43b. Further, the foreign object detection device 40 is fixed to the stay 33 of the discharge device 30 via a fixing member 414 as shown in FIG. 3, and the tip of the arrow in FIG.

  The projector 43 a is first fixed to the holding member 411. The holding member 411 is a metal plate in the embodiment, but may be a resin molded product, and is itself fixed to the rotation direction adjusting member 412. The rotation direction adjusting member 412 determines the direction of the laser light emitted from the projector 43a, and determines the direction of light emission in the YZ plane by rotating around the rotation axis 416 by adjusting means (not shown) such as a screw. I can do it. The rotation direction adjusting member 412 is installed on the Z-axis direction adjusting member 413. The Z-axis direction adjusting member 413 can adjust the position (height) of the laser beam in the Z direction by adjusting means (not shown) such as a screw. In other words, the light projector 43 a held by the holding member 411 is optically adjusted by the rotation direction adjusting member 412 and the Z-axis direction adjusting member 413. The Z-axis direction adjusting member 413 is fixed to the fixing member 414. Therefore, the light projector 43 a, the holding member 411, and the adjustment members 412 and 413 are installed on the fixing member 414.

  Here, as is clear from FIG. 4, the projector 43 a is attached in an overhanging state from the rotation direction adjusting member 412. Since the foreign matter detection device 40 depends on the function of the optical axis coincidence of the projector 43a and the light receiver 43b, it is necessary to stably fix the projector 43a and the light receiver 43b. The embodiment of the present invention addresses this problem as described in detail below.

  The L-shaped member 45 (displacement restricting member) holds the projector 43a that has finished the optical axis adjustment from the lower side in the Z-axis direction and restricts the movement in the rotational direction. For convenience of explanation, the L-shaped member 45 is shown in a cross section in FIG. A problem in mounting a holding member such as the L-shaped member 45 is that the L-shaped member 45 is fixed to the plate 44 with screws. That is, in the case of a type that is fixed with a screw, when the L-shaped member 45 is fixed, the member is rotated by the rotation of the fixing screw, and as a result, the fixing position of the projector 43a is affected and the adjusted optical axis is deviated. . Therefore, in the embodiment, for fixing the L-shaped member 45, an elastic member 47 is provided on the contact surface with the projector 43a. The elastic member 47 is made of a rubber material in the embodiment. The material of the rubber material does not need to be specified in particular, but the hardness is preferably 70 degrees or less. The elastic member 47 may be made of a material having the same elasticity other than the rubber material, such as foamed resin. Furthermore, in the embodiment, the elastic member 47 is bonded to the L-shaped member 45, but may be fixed by a method other than bonding, such as a pressing member.

  As described above, fixing the L-shaped member 45 with a screw or the like induces a positional shift of the projector 43a. Therefore, in the embodiment, the magnet 46 is fixed to the L-shaped member 45, and the L-shaped member 45 is configured to be freely contacted and separated from the fixed member 414. Here, the plate 44 is a plate to be attracted by the magnet 46, is fixed to the fixing member 414, and is made of a magnetic material such as SUS410 in the embodiment.

  In the manufacturing process of liquid crystals and semiconductors, it is necessary to suppress the generation of particles as much as possible. However, in general, magnetic materials easily rust, and the resulting rust easily becomes particles, so the use of magnetic materials is limited. Since the embodiment is assumed to be used in the liquid crystal process, the fixing member 414 is made of SUS304, which is a nonmagnetic material, and therefore a magnet adsorption plate 44 is installed. Therefore, in a process that does not require consideration of particles, the plate 44 can be omitted by using the fixing member 414 as a magnetic material.

  Further, since the magnet 46 is attracted to the plate 44, if it is separated from the plate 44 directly by hand or the like, the L-shaped member 45 may come into contact with the projector 43a during the operation, and as a result, the optical axis may be distorted. . Therefore, in the embodiment, an actuating member 48 (for example, a ball plunger) for separation operation is provided, and this actuating member 48 solves the problem that the optical axis of the projector 43a is out of order when the L-shaped member 45 is removed. Can do. In other words, the actuating member 48 is a member in which a metal ball is incorporated at the tip portion of the screw member, and is assembled to the opening 451 of the L-shaped member 45 with the tip portion facing the plate 44 side. Then, by rotating a tool such as a hexagon wrench at the end opposite to the tip, for example, the actuating member 48 can be moved back and forth so as to be in contact with and away from the plate 44. .

  By this operating member 48, it is possible to detach the L-shaped member 45 while preventing the optical axis of the projector 43a from being affected. That is, when the L-shaped member 45 is attached, the L-shaped member 45 is attached to the plate 44 while being in contact with the projector 43a in a state where the metal ball protrudes from the surface position of the magnet 46. Then, by rotating the operating member, the metal ball is positioned inside the surface position of the magnet 46, and the magnet 46 and the plate 44 are completely brought into close contact with each other. Thereby, the light projector 43a can be fixed without affecting the optical axis. When removing the L-shaped member 45, the operating member 48 is rotated to cause the metal ball to protrude from the surface position of the magnet 46. Thereby, since the attractive force by the magnetic force of the magnet 46 and the plate 44 is reduced, the L-shaped member 45 can be easily removed. That is, the L-shaped member 45 can be removed without affecting the optical axis of the projector 43a.

The metal ball at the tip is installed so as to be rotatable with respect to the screw incorporated in the operating member 48. Therefore, even if the screw incorporated in the actuating member 48 is rotated, the plate 44 is displaced in rotation. The magnet 46 can be separated without being generated. FIG. 4 shows only one actuating member 48, but in order to stabilize the L-shaped member 45, it is preferable to install a plurality of actuating members 48.

  Thus, since the L-shaped member 45 is contacted and separated almost vertically by the actuating member 48, it is possible to prevent an unintentional force from being applied to the projector 43a at the time of contact and separation, and the optical axis from being misaligned.

  In the above-described embodiment, the example in which the L-shaped member 45 is used as the displacement regulating member has been described. However, the member that abuts on the light projector 43a and the fixing member 414 or the member that abuts on the light receiver 43b and the fixing member 414. What is necessary is just to have what the displacement of the light projector 43a and the light receiver 43b is controlled by this displacement control member.

  In the above embodiment, the actuating member 48 uses a mechanism based on the appearance of a metal ball. However, other mechanisms that exhibit the same effect, such as a rack / pinion mechanism, can be used. . Furthermore, it is also possible to perform electrical contact / separation using a magnet as an electromagnet.

  In the description of the present invention, the substrate treatment is applied to the substrate, but the present invention is applied to any device that scans close to the substrate in the same manner as a coating apparatus such as a proxy exposure machine. It is possible.

DESCRIPTION OF SYMBOLS 1 Application | coating apparatus 10 Substrate 11 Machine stand 21 Stage 30 Discharge part 31 Slit nozzle 32 Side plate 33 Stay 34 Base raising mechanism 40 Foreign object detection device 411 Holding member 412 Rotation direction adjustment member 413 Z-axis direction adjustment member 414 Fixing member 416 Rotation shaft 43a Emitter 43b Light receiver 44 Plate 45 L-shaped member 451 Opening 46 Magnet 47 Elastic body 48 Actuating member 49 Foreign material 49a Foreign material (top)
49b Foreign object (bottom)
50 Optical axis 51 Coating liquid supply mechanism 52 Buffer tank 53 Control valve 54 Piping 55 Coating liquid supply tank

Claims (1)

A discharge device that scans the substrate by moving relative to the sheet-like substrate and forms a predetermined layer on the substrate surface by discharging a processing liquid onto the substrate surface, and is disposed upstream of the discharge device in the scanning direction. A coating device having at least a foreign matter detection device for detecting foreign matter on the substrate,
The foreign object detection device includes:
A light projecting device that irradiates laser light parallel to the substrate surface;
A light receiving device for receiving the projected laser beam;
A fixing member that supports the light projecting device and the light receiving device so that the optical axis can be adjusted;
A displacement regulating member that abuts on each of the light projecting device and the light receiving device and the fixing member and regulates displacement of the light projecting device and the light receiving device;
The has, the displacement regulating member has a sheet-like elastic body surface contacting the light emitting device or a light receiving device,
The displacement restricting member is held so as to be able to come into contact with and separate from the fixed member, and the displacement restricting member is provided with an operating member that can project toward the fixed member, and the operating member causes the displacement restricting member to move. A coating apparatus, wherein a contact / separation operation is performed on the fixing member .

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