JP3571438B2 - Coating device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a coating apparatus that applies a coating liquid to a glass substrate or the like of a color filter for LCD.
[0002]
[Problems to be solved by the invention]
In general, a spin coating method is often used as a method of applying a coating liquid to a large glass substrate such as a color filter for an LCD.
[0003]
This spin coating method includes an open-air type and a closed cup type, but both methods have drawbacks in that the coating efficiency is as low as about 10% and the coating film thickness in the corner portion of the substrate becomes too thick. As the size of the substrate is expected to increase in the future, problems have been pointed out with respect to the use amount of the coating solution, the film thickness distribution, the throughput, and the like.
[0004]
As a method for solving the above-mentioned drawbacks of the spin coating method, there are a knife coating method, a roll coating method, and a die coating method.
[0005]
In each of these methods, a coating clearance is provided on a substrate to be coated, and the coating film thickness is determined by the set value to obtain the smoothness of the coating surface. It is difficult to obtain a uniform film thickness when the degree (degree of unevenness) is lower than the coating accuracy (the degree of unevenness is large).
[0006]
A dip coating method is generally known as a method of applying a coating liquid that is not easily affected by unevenness on the substrate surface. However, in this method, it is essential to cover a non-coated portion, and the operation is complicated. It becomes.
[0007]
A method similar to the principle of the dip coating method and a method of selectively applying the coating liquid only to the main surface of the substrate is described in Yuji Ozaki of Sogo Gijutsu Center (April 30, 1988). A coating method of a coating liquid described on page 336 of the book "Advances in Latest Coating Technology" is known.
[0008]
In this method, a coating liquid is supplied in a substantially horizontal direction from a die head or a slide die, and a base is relatively vertically moved to a position close to a die lip formed on a side surface of the die head or the slide die. The coating liquid supplied from the die head or the slide die forms a bead between the base and the die lip, and is applied to the main surface of the base as the base moves upward to form a coating film.
[0009]
This coating method is generally used as a coating method for a continuous substrate. The thickness of the applied coating liquid is determined by the relative speed between the substrate and the coating head and the viscosity of the coating liquid. That is, since the coating liquid pulled up from the bead formed between the base and the die lip falls along the base under the influence of gravity, the film is formed by a balance between the speed of the drop and the speed at which the base pulls up the coating liquid. The thickness is determined.
[0010]
In this coating method, when the coating liquid has low viscosity and low surface tension, it is difficult to form a bead in the clearance provided between the base and the coating head, and the coating liquid is supplied. Immediately after, it may fall by gravity without forming a bead. To prevent this, there is a problem that the clearance between the base and the coating head must be made extremely small.
[0011]
However, when the substrate has low flatness like a glass substrate for an LCD color filter and has irregularities as large as 100 μm, a difference occurs in the tensile force generated when the coating liquid is pulled up from the bead, and the beads have various different characteristics. Shear force will act. When a different shearing force acts locally on the bead as described above, the amount of the coating liquid drawn out from the bead is not uniform, and thus the film thickness is not uniform.
[0012]
Furthermore, in this coating method, even though the coating liquid can be continuously applied to the main surface of the base, the main surface of the base is vertical and the coating liquid is supplied from a direction perpendicular to the base. When applying a coating liquid to a plurality of discontinuous substrates such as a single-wafer substrate, the coating liquid remaining in the bead drops by gravity when the rearmost end of the substrate in the sliding direction passes through the bead. In addition, contamination may be caused by adhering to the tip of the substrate to be coated next, the back surface thereof, and the lower part of the coating head. For this reason, this coating method is unsuitable for use in coating a single-wafer substrate.
[0013]
The coating method using a slide die also has the same disadvantages as the coating method using the die head described above. In particular, in the coating method using the slide die, since the coating liquid flows freely on the inclined surface of the slide die to form a bead between the slide die and the surface of the base, the supply of the coating liquid is stopped at any time. It is difficult to apply the coating liquid continuously to a discontinuous substrate such as a single-wafer substrate.
[0014]
Therefore, there has been proposed a coating apparatus capable of solving the drawbacks in the respective coating methods as described above and forming a uniform coating film in a stable state on a single-wafer substrate without being affected by the physical properties of the coating liquid. (Japanese Unexamined Patent Publication No. 5-146775).
[0015]
As shown in FIG. 8, this coating device is a linear device that is attached between a pair of support frames 1A of the device main body 1 in such a manner that the downstream end in the sliding direction of the substrate S is inclined to be higher. A guide frame 2, a substrate holder 3 slidably attached to the guide frame 2, and a linear slit 4 a that opens upward, and the slit 4 a extends in a direction orthogonal to the axial direction of the guide frame 2. And a coating head 4 disposed below the guide frame 2.
[0016]
The substrate holder 3 is screwed to a ball screw 5 provided along the guide frame 2, and is slid along the guide frame 2 by rotating the ball screw 5 by the motor M. The substrate S is sucked and held on the downward suction surface thereof by the operation of a suction mechanism (not shown) connected to the suction pipe connecting portion 3A. The coating head 4 discharges the coating liquid supplied from a coating liquid supply mechanism (not shown) upward from the slit 4a.
[0017]
FIG. 9 shows a state of the coating apparatus at the start of coating, in which the substrate S sucked on the suction surface of the substrate holder 3 has its tip end immediately above the slit 4 a of the coating head 4 via a predetermined clearance. And are opposed to each other.
[0018]
When the coating liquid R is supplied to the coating head 4 from the coating liquid supply mechanism, the supplied coating liquid R is discharged from the slit 4a to form a bead B as shown in an enlarged view in FIG. Adhere to the lower surface of the tip of the substrate S. At this time, the minimum clearance C1 between the opening of the slit 4a and the lower surface of the substrate S adsorbed on the substrate holder 3 is such that the viscosity and surface tension of the coating liquid R do not leak out of the bead B. It is set in consideration of physical properties such as.
[0019]
10, a meniscus L1 is formed on the rear end side (left side in the figure) of the substrate S of the bead B and a meniscus L2 is formed on the front end side (right side in the figure). The height dimension h1 of the meniscus L1 The height dimension h2 of L2 has a relationship of h1 <h2 because the guide frame 2 is inclined at the angle θ.
[0020]
When the motor M is driven from the state of FIG. 9 and the ball screw 5 is rotated, the substrate holder 3 is slid obliquely upward along the guide frame 2 at a constant speed.
[0021]
As a result, as shown in FIGS. 11 and 12, the coating liquid R is sequentially deposited on the lower surface of the substrate S from the bead B, and a layer Ra of the coating liquid R is formed. At this time, the application liquid R is continuously supplied to the application head 4, and the amount of the application liquid R in the bead B is kept constant.
[0022]
Then, as shown in FIG. 13, when the substrate S rises along the guide frame 2 and the rear end S2 reaches the slit 4a of the coating head 4, the sliding of the substrate holder 3 is stopped, and the coating head is further moved. The application liquid R forming the bead B is sucked into the coating head 4 by the operation of the suckback valve (not shown) connected to the nozzle 4, and the bead B disappears. Thus, the coating head 4 is separated from the coating liquid layer Ra on the substrate S.
[0023]
Thereafter, the substrate S is removed from the substrate holder 3, held horizontally in an upward or downward state, conveyed to a drying unit (not shown), dried by means such as a far-infrared heater, and dried on the main surface of the substrate S. A coating film having a uniform thickness is formed.
[0024]
In general, the main surface of a glass substrate for an LCD color filter has low smoothness, and usually has irregularities of 50 to 70 μm, and at most about 100 μm. In addition, by maintaining a sufficiently large clearance of 10 to 1000 times, preferably 20 times or more with respect to the thickness of the layer Ra formed on the substrate S, it is possible to reduce the influence of irregularities on the main surface of the substrate S. it can. Furthermore, since the application of the coating liquid to the substrate S is performed in a state where the substrate S is inclined (5 to 20 degrees, preferably 11 degrees), the lower the coating liquid applied along the main surface of the substrate S , Whereby the surface of the coating film can be smoothed.
[0025]
However, when the coating liquid is continuously applied to the single-wafer substrate by the above-described conventional coating apparatus, after the application of the coating liquid to one substrate S is completed, the substrate holder 3 is turned over and the substrate S is sucked. Is released and the substrate S is removed. Then, a new substrate S is adsorbed and set on the substrate holder 3, and the substrate holder 3 is slid along the guide frame 2 in the direction opposite to the direction of the application of the application liquid to be applied. It is necessary to return to the starting position.
[0026]
For this reason, the processing time per substrate becomes long, and the processing is limited to about 30 substrates / hour at the maximum.
[0027]
The present invention has been made in view of the above-described circumstances, and can form a smooth and uniform coating film on a single-wafer substrate without being affected by the physical properties of a coating solution. An object of the present invention is to provide a coating apparatus capable of increasing the number of processed sheets per time.
[0028]
[Means for Solving the Problems]
In order to achieve the above object, a coating apparatus according to the present invention includes a coating head having a band-shaped slit that opens upward and extends in a horizontal direction, and moves obliquely upward above the coating head and holds a substrate. And a slider that conveys the surface of the substrate to be coated while facing the coating head. The slider supplies a coating liquid to the coating head when the slider moves while holding the substrate. A bead is formed by the coating liquid discharged from the slit of the coating head in between, and the coating liquid is applied to the substrate by applying the coating liquid to the surface where the substrate is to be coated from the bead as the substrate moves. In the coating apparatus to be performed, a direction perpendicular to the direction in which the slit of the coating head extends above the coating head, and the upper part of the coating head is linearly obliquely upward. A plurality of sets of guide members are disposed, and sliders are respectively slidably attached to the plurality of sets of guide members, and the plurality of sliders are reciprocated along the guide members by driving members connected to the respective sliders. Each slider detachably holds a substrate on which the coating liquid is to be applied, and holds the held substrate in a state in which the substrate is parallel to the moving direction of the slider and faces the coating head. A configuration is provided in which a substrate holding member that can be positioned is provided at a first position to be positioned and a second position to position the substrate away from a position facing the coating head.
[0029]
In such a coating apparatus of the present invention, after the substrate is held by the substrate holding member of the slider and the substrate holding member holding the substrate is located at the first position, the surface on which the substrate is coated is opposed to the coating head. Meanwhile, the slider is slid linearly in an obliquely upward direction above the application head along the guide member by the operation of the driving member.
[0030]
At this time, the coating liquid is continuously supplied to the coating head, and the coating liquid is discharged upward from the slit to form a bead of the coating liquid between the coating head and the surface of the substrate that moves above the coating head. I do.
[0031]
Then, as the slider and the substrate move, the coating liquid is sequentially attached from the beads to the surface on which the substrate is to be coated, and a layer of the coating liquid is formed on the substrate.
[0032]
When the application of the application liquid to the substrate is completed in this way, after the substrate holding member of the slider is positioned at the second position, the slider is slid in the opposite direction along the guide member by the operation of the driving member, The position is returned to the position at the start of application of the application liquid. Then, while the slider returns to the position at the start of the application of the application liquid, the substrate held by the substrate holding member is replaced.
[0033]
The above-described step of applying the application liquid to the substrate is performed for each of the plurality of sliders.
[0034]
At this time, the reciprocating strokes of the sliders along the guide member are shifted from each other so that the coating of the substrate by the coating head and the replacement of the substrate after the coating are performed alternately for each slider. can do. Thus, the application to the substrate by one application head can be performed continuously without a gap.
[0035]
In order to achieve the above object, a coating apparatus according to the present invention provides a coating apparatus in which a coating head, a guide member, and a slider are rotatable about an axis extending in a horizontal direction and perpendicular to a sliding direction of the slider. It was configured to be attached to the frame.
[0036]
In the coating apparatus according to the present invention, the inclination angle of the guide member, that is, the slide angle of the slider, is obtained by rotating the machine frame about an axis extending in the horizontal direction and at right angles to the slide direction of the slider. In addition, the inclination angle of the substrate held by the substrate holding member of the slider is set to an arbitrary angle.
[0037]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the most preferred embodiment of the present invention will be described.
[0038]
FIG. 1 is a side view of the coating apparatus 10 in this embodiment, and FIG. 2 is a front view of the coating apparatus 10 in FIG.
[0039]
1 and 2, the coating apparatus 10 has a frame 11A and a frame 11B attached to both sides of a main body 11 of the apparatus, and upper ends of the frames 11A and 11B are rotatably supported by a machine frame (not shown). The main body 11 is pivoted about and tilted.
[0040]
When the sliders 13A and 13B, which will be described later, are positioned at the replacement position of the substrate S, the center of rotation P of the main body 11 is the axial center of the holder support shafts 15A and 15B rotatably attached to the sliders 13A and 13B. Is to match.
[0041]
An upper stage 11C is provided on the upper surface of the main body 11, and a lower stage 11D parallel to the upper stage 11C is provided below the upper stage 11C.
[0042]
As shown in FIG. 2, the upper stage 11 </ b> C has a groove 11 </ b> E that extends vertically through the upper stage 11 </ b> C and extends along the longitudinal direction of the main body 11 at the center thereof. On the upper surface of the upper right stage 11Ca and upper left stage 11Cb of the upper stage 11C divided into right and left by the groove 11E, ball screws 12A and 12B extending in parallel with the groove 11E are mounted with both ends rotatably supported. The ball screws 12A and 12B are separately rotated at a low speed by a drive motor (not shown).
[0043]
Sliders 13A and 13B are connected to the respective ball screws 12A and 12B by screwing connection portions 13a and 13b attached to the lower surfaces thereof, respectively. The rotation of the ball screws 12A and 12B allows the sliders 13A and 13B to be inserted into the grooves 11E. It is slid along.
[0044]
The slider 13A is guided in parallel with the groove 11E by a pair of linear guides 14A disposed on both sides of the ball screw 12A and interposed between the slider 13A and the upper right stage 11Ca. In addition, a pair of linear guides 14B disposed on both sides of the ball screw 12B and interposed between the slider 13B and the upper left stage 11Cb are guided in parallel with the groove 11E.
[0045]
A holder support shaft 15A is rotatably supported at both ends so as to extend horizontally and in a direction perpendicular to the axial direction of the ball screw 12A on the upper surface of the slider 13A. A motor MA is connected to the outer end (the right end in FIG. 2) of the holder support shaft 15A, and the holder support shaft 15A is rotated by driving the motor MA.
[0046]
A base end of the holder support arm 16A is fixed to an inner end (left end in FIG. 2) of the holder support shaft 15A so that the holder support arm 16A extends in a direction perpendicular to the axial direction of the shaft 15A. The rotation of the support shaft 15A rotates counterclockwise in FIG. 1 in a plane perpendicular to the upper right stage 11Ca. When the holder support arm 16A is positioned downward with respect to the upper right stage 11Ca, its tip portion is located below the upper right stage 11Ca through the right half area of the groove 11E.
[0047]
At the tip of the holder support arm 16A, a suction plate 17A for sucking and holding the substrate S is attached in a direction perpendicular to the axial direction of the holder support arm 16A.
[0048]
In FIG. 1, when the slider 13A is located at the retracted position (left position in FIG. 1) with respect to the main body 11, the holder supporting arm 16A is moved into the groove 11E by the rotation of the holder supporting shaft 15A. As it enters from the end, it is inserted below the upper right stage 11Ca from the position above the upper right stage 11Ca through an opening formed in the left side wall of the main body 11. When the slider 13A is located at the forward position (right position in the drawing) with respect to the main body 11, the holder support arm 16A is detached from the right end of the groove 11E by the rotation of the holder support shaft 15A. Thus, it escapes from a position below the upper right stage 11Ca to above the upper right stage 11Ca through an opening formed in the right side wall of the main body 11.
[0049]
A compressor (not shown) is connected to the suction plate 17A so that the substrate S is sucked and held on a suction surface formed on the lower surface of the suction plate 17A. Note that chucks may be attached to four positions of the suction plate 17A, and the substrate S may be held by the chucks.
[0050]
Like the slider 13A, the holder support shaft 15B is rotatably supported at both ends thereof so as to extend in the horizontal direction and in a direction orthogonal to the axial direction of the ball screw 12B, on the upper surface of the slider 13B. ing. A motor MB is connected to an outer end (left end in FIG. 2) of the holder support shaft 15B, and the holder support shaft 15B is rotated by driving the motor MB.
[0051]
A holder support arm 16B has a base end fixed to an inner end (right end in FIG. 2) of the holder support shaft 15B so as to extend in a direction perpendicular to the axial direction of the shaft 15B. The rotation of the support shaft 15B rotates counterclockwise in FIG. 1 in a plane perpendicular to the upper right stage 11Ca. When the holder support arm 16B is positioned downward with respect to the upper left stage 11Cb, its tip is positioned below the upper left stage 11Cb through the left half area of the groove 11E.
[0052]
At the tip of the holder support arm 16B, a suction plate 17B for sucking and holding the substrate S is attached at right angles to the axial direction of the holder support arm 16B.
[0053]
In FIG. 1, when the slider 13B is located at the retracted position (left position in FIG. 1) with respect to the main body 11, the holder support arm 16B is moved to the groove 11E by the rotation of the holder support shaft 15B. As it enters from the end, it is inserted below the upper left stage 11Cb from the position above the upper left stage 11Cb through an opening formed in the left side wall of the main body 11. When the slider 13B is located at the forward position (the right position in the drawing) with respect to the main body 11, the holder support arm 16B is detached from the right end of the groove 11E by the rotation of the holder support shaft 15B. Thus, the main body 11 can escape from a position below the upper left stage 11Cb through an opening formed in the right side wall of the main body 11 above the upper left stage 11Cb.
[0054]
Similar to the suction plate 17A, a compressor (not shown) is connected to the suction plate 17B, and the suction plate 17B sucks and holds the substrate S on a suction surface formed on the lower surface of the suction plate 17B. Note that chucks may be attached to four positions of the suction plate 17B, and the substrate S may be held by the chucks.
[0055]
As described above, the holder support shafts 15A and 15B, the holder support arms 16A and 16B, and the suction plates 17A and 17B are symmetrical with respect to the groove 11E.
[0056]
An elevating mechanism 18 is attached to the lower stage 11D. On the elevating mechanism 18, a coating head 19 having a linear slit 19a that is open upward is arranged such that the slit 19a is orthogonal to the longitudinal direction of the groove 11E and horizontal And is vertically moved by the operation of the lifting mechanism 18.
[0057]
The coating head 19 is mounted so as to be inclined to the right side in FIG. 1 by a predetermined angle with respect to the vertical direction of the upper stage 11C, and this inclination angle is set when the coating apparatus 10 is inclined as described later. In addition, the angle is set such that the coating head 19 is oriented substantially vertically.
[0058]
As shown in FIG. 1, the application head 19 is provided with a suction plate 17A when the slider 13A or 13B is located at the retreat position (left side in the figure) and the application of the application liquid to the substrate S is started. Alternatively, when the slider 13A or 13B is positioned at the forward position (right side in the drawing) and the application of the application liquid to the substrate S is completed, the suction plate 17A or It is arranged so as to be located behind the rear end of the substrate S held by 17B.
[0059]
The coating liquid is supplied to the coating head 19 from a coating liquid supply mechanism described later, and the coating liquid supplied to the coating head 19 is discharged upward from the slit 19a. ing.
[0060]
FIGS. 3 to 6 show examples of the shape of the coating head 19.
[0061]
3 to 6, the main body 19A of the coating head 19 has a length a equal to or larger than the width of the substrate S on which the coating liquid is to be coated, and extends in the center of the upper surface along the axial direction and faces upward. A slit 19a is formed. A pair of slopes 19B and 19C are formed on both sides of the slit 19a.
[0062]
Inside the main body 19A, there is formed a hollow liquid reservoir 19D extending in parallel with the slit 19a and communicating with the slit 19a over the entire area in the axial direction. A coating liquid supply pipe 19E attached to a lower portion of the slit 19a is connected to the liquid pool 19D, and the coating liquid introduced from the coating liquid supply pipe 19E is discharged from the slit 19a through the liquid pool 19D. It has become.
[0063]
In the drawing, reference numeral 19F denotes a pair of slit length adjusting packings which are detachably fitted to both ends of the slit 19a, respectively. The slit length adjusting packing 19F has another slit length having a different length. The width of the application liquid discharged from the slit 19a can be adjusted by replacing the packing with an adjustment packing.
[0064]
The dimensions of each part of the coating head 19 shown in the figure are as follows.
[0065]
Length a of main body 19A = 400 mm
Width b of main body 19A = 50 mm
Height c of main body 19A = 80 mm
Length d of slit 19a (width after adjustment by slit length adjusting packing 19F) = 350 mm
The width e of the slit 19a = 2 mm
Depth f of slit 19a = 27mm
The depth g of the sump 19D = 40 mm
As a coating liquid supply mechanism for supplying the coating liquid to the coating head 19, a mechanism as shown in FIG.
[0066]
The coating liquid supply mechanism pushes out the coating liquid contained in the pressurized tank barrel 20 by air pressure supplied through a manual valve 21, and performs a coarse adjustment needle valve 22, a filter 23, a flow meter 24, and a fine adjustment. Is supplied to the coating head 19 via the needle valve 25 for use, the air operated valve 26 and the suck back valve 27.
[0067]
The air-operated valve 26 automatically operates by air pressure when the application of the coating liquid onto the substrate S is completed, and stops the supply of the coating liquid to the coating head 19. The suck-back valve 27 is supplied to the coating head 19 by closing the air-operated valve 26 and simultaneously causing the piston 27a to slide in the direction of the arrow shown in FIG. 7 to generate a negative pressure in the cylinder 27b. The application liquid is sucked and collected.
[0068]
Next, the operation of the coating device will be described.
[0069]
Before the start of coating, the coating device 10 is rotated by a drive mechanism (not shown) around the rotation center P so that the right end in FIG. 1 is directed upward, and the inclination angle is set to a predetermined angle θ. Is done.
[0070]
When the slider 13A is located at the retracted position (the left position in FIG. 1, hereinafter referred to as an application start position) on the upper right stage 11Ca, the holder support arm 16A is positioned so as to be directed downward at a right angle to the upper right stage 11Ca. The suction plate 17A is located between the upper right stage 11Ca and the lower stage 11D. At this time, the substrate S sucked on the suction surface of the suction plate 17A is held so as to be parallel to the sliding direction of the slider 13A.
[0071]
In this state, the ball screw 12A is rotated, and the slider 13A is slid from left to right in FIG. 1 at a constant speed, whereby the suction plate 17A and the substrate S sucked by the suction plate 17A slide in parallel with the upper right stage 11Ca. Is done.
[0072]
Almost simultaneously with the start of the sliding of the ball screw 12A, the supply of the coating liquid to the coating head 19 is started, and the supplied coating liquid is discharged from the slit 19a to form a bead and adhere to the substrate S. . At this time, the distance between the substrate S and the slit 19a of the coating head 19 is adjusted by moving the coating head 19 up and down by the elevating mechanism 18.
[0073]
Then, with the movement of the substrate S, the coating liquid is sequentially adhered to the lower surface of the substrate S from the beads formed on the coating head 19 to form a layer of the coating liquid.
[0074]
When the slider 13A reaches the forward position (the right position in FIG. 1, hereinafter referred to as the coating end position), the rear end of the substrate S comes off from above the coating head 19, and at the same time, the sliding of the slider 13A is stopped. At the same time, the suck back valve 27 connected to the coating head 19 is operated, and the coating liquid forming the bead is sucked into the coating head 19 and the bead disappears. Thus, the coating liquid applied to the coating head 19 and the substrate S is separated.
[0075]
The method of applying the coating liquid to the substrate S described above is the same as the conventional method of applying the coating liquid described with reference to FIGS.
[0076]
As described above, when the slider 13A reaches the application end position and the application of the application liquid to the substrate S held by the suction plate 17A is completed, the motor MA is driven to drive the holder support shaft 15A and the holder support arm 16A. Is rotated counterclockwise, whereby the suction plate 17A and the substrate S held by the suction plate 17A are moved above the upper right stage 11Ca to be held in a horizontal state.
[0077]
While maintaining this state, the ball screw 12A is rotated in the opposite direction to the above, and the slider 13A is moved in the direction of the application start position (leftward in FIG. 1). Then, it is temporarily stopped at an intermediate position between the application end position and the application start position.
[0078]
At this position, the substrate S held upward on the suction plate 17A is exchanged by a substrate exchange device (not shown). That is, after the suction of the substrate S by the suction plate 17A is released and the substrate S on which the coating liquid is applied is removed, a new substrate S is placed and suctioned by the suction plate 17A.
[0079]
At the substrate exchange position, the axis of the holder support shaft 15A of the slider 13A stopped at the substrate exchange position coincides with the rotation center P of the coating device 10, so that the inclination angle of the coating device 10 has changed. In this case, the position of the suction plate 17A does not change. For this reason, the positional relationship with the substrate exchanging device and other devices does not change, so that it is not necessary to adjust the positional relationship with the substrate exchanging device and the like every time the inclination angle of the coating device 10 is changed.
[0080]
After the replacement of the substrate S is completed as described above, the slider 13A is moved in the direction of the coating start position again, and stopped after reaching the coating start position. Thereafter, the motor MA is driven to rotate the holder support shaft 15A and the holder support arm 16A counterclockwise, and the suction plate 17A and the substrate S sucked by the suction plate 17A are moved to the upper right stage 11Ca and the lower stage 11D. And is held so as to be parallel to the sliding direction of the slider 13A.
[0081]
Then, by repeating the above steps, the application of the coating liquid is continuously performed on the single-wafer substrate S.
[0082]
Similarly to the slider 13A, the slider 13B is reciprocated between the coating start position and the coating end position. During this time, the coating liquid is applied to the substrate S held on the suction plate 17B through the same steps as described above. Is performed.
[0083]
Here, the reciprocating stroke of the slider 13B is performed half a stroke behind the reciprocating stroke of the slider 13A. That is, when the slider 13A is moved from the application start position to the application end position, the slider 13B is moved from the application end position to the application start position, and the slider 13B is moved from the application start position to the application end position. During the movement, the slider 13A is moved from the coating end position to the coating start position.
[0084]
Therefore, when the substrate S is being exchanged for the suction plate 17B of the slider 13B, the application liquid is applied to the substrate S held by the suction plate 17A of the slider 13A. During the replacement of the substrate S, the application liquid is applied to the substrate S held on the suction plate 17B of the slider 13B. Accordingly, the application liquid is always applied to the substrate S, and the application liquid can be applied to twice the number of substrates S per unit time as compared with the conventional coating apparatus of FIG. become.
[0085]
In the coating liquid application step, increasing the sliding speed of the sliders 13A and 13B decreases the thickness of the coating liquid layer applied to the substrate S, and conversely, decreasing the sliding speed decreases the thickness of the coating liquid layer. However, by changing the inclination angle θ of the coating apparatus 10, the thickness of the layer of the coating liquid applied to the substrate S can be changed while the sliding speed of the sliders 13A and 13B is kept constant.
[0086]
That is, when the inclination angle θ of the coating apparatus 10 increases, the inclination angle of the substrate S held on the suction plates 17A and 17B also increases, and the thickness of the layer of the coating liquid applied to the substrate S decreases. When the inclination angle θ of the coating device 10 decreases, the inclination angle of the substrate S held by the suction plates 17A and 17B also decreases, and the thickness of the coating liquid applied to the substrate S increases.
[0087]
At this time, since the coating head 19 is also integrally inclined with the inclination of the coating apparatus 10, the relative positional relationship between the coating head 19 and the suction plates 17A and 17B does not change.
[0088]
The substrate Sa on which the coating liquid is applied by the coating apparatus 10 is mainly a large glass substrate for an LCD color filter, but the coating liquid can be applied to other substrates in the same manner. The coating liquid can be applied not only to a non-flexible glass substrate but also to a flexible plastic substrate, a metal substrate, or a paper substrate.
[0089]
The coating liquid used in the coating device 10 is mainly a photosensitive resin for drawing a fine pattern on a substrate, but it goes without saying that other coating liquids can be coated. Various coating liquids such as water-based and solvent-based coatings can be used. Further, pigments, dyes, fillers, sensitizers, resins, additives, and the like can be used alone, or a mixture of several of them can be used. It can also be used.
[0090]
【Example】
Next, the present invention will be described in more detail with reference to examples.
(Example 1)
An LCD color filter glass substrate S having a width of 300 mm, a length of 350 mm and a plate thickness of 1.1 mm was prepared, and a PVA aqueous solution having a solid concentration of 1.0% and a viscosity of 5.0 cps was prepared as a coating liquid.
[0091]
The coating head 19 having the shape and dimensions shown in FIGS. 3 to 6 was used, and the relative angle between the coating head 19 and the substrate S was set to about 8 °. The moving speed of the sliders 13A and 13B was set to 30 mm / sec.
[0092]
Then, the coating liquid was applied to the substrates S held on the suction plates 17A and 17B of the sliders 13A and 13B by the above-described steps. At this time, at the start of coating, the heights h1 and h2 (see FIG. 10) of the meniscuses L1 and L2 of the bead B formed between the coating head 19 and the substrate S are 0.5 mm and 0.7 mm, respectively. Set to.
[0093]
The substrate S coated with the coating liquid under the above conditions was dried in an oven at a temperature of 80 ° C. for 1 minute.
[0094]
As a result, the thickness distribution of the coating film measured in the moving direction of the substrate S and in the direction perpendicular to the moving direction was 20,000 ± 600 ° within the range of 260 mm × 300 mm on the coating surface of the coating liquid. Yes, good results could be obtained.
[0095]
The coating efficiency of the coating liquid on the substrate S at this time was 140 sheets / hour.
[0096]
The ratio of the height h2 of the meniscus L2 to the wet film thickness C2 (see FIG. 12) of the coating film Ra in the coating liquid coating step was C2: h2 = 1: 350.
(Example 2)
A photoresist OFPR-800 having a solid content of 6.5% and a viscosity of 2.5 cps manufactured by Tokyo Ohka Kogyo Co., Ltd. was used in place of the coating solution of Example 1 as a coating solution, and the other conditions were the same as in Example 1. The application liquid was applied to the substrate S.
[0097]
As a result, the thickness distribution of the coating film measured along the moving direction of the substrate S and the direction perpendicular to the moving direction was 10,000 ± 300 ° in the range of 260 mm × 300 mm on the coating surface of the coating liquid. Yes, good results could be obtained.
[0098]
The coating efficiency of the coating liquid on the substrate S at this time was 140 sheets / hour.
[0099]
The ratio of the height h2 of the meniscus L2 to the wet film thickness C2 (see FIG. 12) of the coating film Ra in the coating liquid coating step was C2: h2 = 1: 350.
[0100]
【The invention's effect】
As described in detail above, according to the present invention, the application of the coating liquid is performed by sliding the upper side of the coating head linearly in an obliquely upward direction while the surface on which the substrate is coated is opposed to the coating head. A smooth and uniform coating film can be formed on a discontinuous object such as a substrate without being affected by the properties of the coating solution. And, by reciprocating the reciprocating strokes of the sliders along the guide member, the coating on the substrate by one coating head can be performed continuously without a gap. The number can be increased.
[0101]
Further, by changing the inclination angle of the machine frame, the thickness of the layer of the coating liquid applied to the substrate can be changed while keeping the sliding speed of each slider constant, and a desired thickness corresponding to the physical properties of the coating liquid can be obtained. A coating film having the same thickness can be formed.
[Brief description of the drawings]
FIG. 1 is a side view showing an example of the best mode of the present invention.
FIG. 2 is a front view of the same example as viewed from the direction of arrow X in FIG.
FIG. 3 is a perspective view showing an example of a coating head used in the example.
FIG. 4 is a front view of the coating head.
FIG. 5 is a plan view of the coating head.
FIG. 6 is a side view of the coating head.
FIG. 7 is a circuit diagram showing a coating liquid supply mechanism used in the example.
FIG. 8 is a side view showing a conventional coating apparatus.
FIG. 9 is a schematic side view showing a relationship between a substrate and a bead at the start of coating in the conventional example.
FIG. 10 is an explanatory diagram showing an enlarged view of a state of a bead at the start of coating in the conventional example.
FIG. 11 is a schematic side view showing the relationship between a substrate during coating and a bead in the conventional example.
FIG. 12 is an enlarged view showing a state of a bead during application in the conventional example.
FIG. 13 is a schematic side view showing a relationship between a substrate and a bead at the end of coating in the conventional example.
[Explanation of symbols]
10 ... coating equipment
11 ... body (machine frame)
11A, 11B ... frame
11C: Upper stage
11Ca ... Top right stage
11Cb: Upper left stage
11D: Lower stage
11E ... groove
12A, 12B ... ball screw (drive member)
13A, 13B ... slider
14A, 14B ... linear guide (guide member)
15A, 15B ... holder support shaft (substrate holding member)
16A, 16B: Holder support arm (substrate holding member)
17A, 17B: suction plate (substrate holding member)
19… Coating head
19a ... Slit

Claims (2)

A coating head having a band-shaped slit that opens upward and extends in the horizontal direction, and moves obliquely upward above the coating head, holds the substrate, and faces the coating surface of the substrate to the coating head. A coating liquid supplied to the coating head when the slider moves while holding the substrate, and a bead is formed between the coating head and the substrate by the coating liquid discharged from the slit of the coating head. Forming, in a coating apparatus for applying the coating liquid to the substrate by applying a coating liquid in a layer form on the surface where the substrate is coated from the bead with the movement of the substrate,
A plurality of sets of guide members are arranged above the coating head and extend linearly in a direction perpendicular to the direction in which the slit of the coating head extends and obliquely upward above the coating head,
The sliders are respectively slidably attached to the plurality of sets of guide members, and the plurality of sliders are reciprocated along the guide members by drive members connected to the respective sliders,
A first position in which each slider detachably holds a substrate on which a coating liquid is applied and positions the held substrate in a state parallel to the moving direction of the slider and opposite to the coating head; A substrate holding member that can be positioned at a second position where the substrate is separated from a position facing the coating head.
A coating device characterized by the above-mentioned. 2. The apparatus according to claim 1, wherein the application head, the guide member, and the slider are mounted on a machine frame that is rotatable about an axis extending in a horizontal direction and perpendicular to a sliding direction of the slider. Coating equipment.

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