TWI410284B - Apparatus for providing photoresist of slit coater - Google Patents

Abstract

A device for supplying a coating solution of a slit coater is provided to shorten the path through which the coating solution is supplied, thereby preventing a delay in ejection of the coating solution, and to enable scale up of the capacity of a pump, thereby improving the quality of a slit coater. A device(3) for supplying a coating solution of a slit coater comprises: a piston(20); and a cylinder(30) including a piston running portion(11) into which the piston is inserted so that the piston reciprocates along the horizontal direction, and an extended portion(13) formed by enlarging the space from the end of the piston running portion along the longitudinal direction. A feeding valve(V1) for controlling the supply of the coating solution is linked to the piston running portion, and an ejection valve(V2) for controlling the ejection of the coating solution is linked to the bottom of the extended portion.

Description

Coating liquid supply device for slit coater

The present invention relates to a coating liquid supply device for a slit coater, and more particularly to a coating liquid for a slit coater that supplies a coating liquid filled in a storage tank to a slit coater. Supply device.

Generally, a method of uniformly coating a photoresist (PR: hereinafter referred to as a coating liquid) in a photolithography process includes: after loading a coating liquid on the outside of a circular roller, rolling the roller in a certain direction on the substrate a method of applying a coating liquid onto the substrate, thereby placing the substrate on the disk support, rotating the coating liquid in the center of the substrate, and rotating the substrate to perform coating on the substrate by centrifugal force. A spin coating method is a slit coating method in which a coating liquid is sprayed onto a substrate while being sprayed in a predetermined direction through a nozzle in a slit form.

However, the larger the substrate, the heavier it is, and the more difficult it is to rotate the substrate at high speed. Further, there is a problem that the substrate is damaged and the energy consumption is large when the substrate is rotated at a high speed. Therefore, a slit coating method is mainly used for a substrate for a flat panel display device such as a glass substrate for a liquid crystal display panel.

The slit coating device for performing the slit coating comprises: a substrate chuck for mounting a substrate; a pre-discharging portion disposed on a side of the substrate chuck; and a top portion of the substrate chuck and the pre-ejection portion A horizontally moving slit nozzle that ejects a coating liquid on a substrate. In other words, the slit nozzle is horizontally moved toward the substrate chuck side on which the substrate is mounted after being pre-discharged from the upper portion of the pre-discharge portion, and the slit nozzle is uniformly moved and ejected in order to uniformly distribute the coating liquid on the substrate. Coating solution.

1 and 2 are a side view and a perspective view of a substrate coating apparatus equipped with an ultrasonic cleaning device according to the prior art.

As is apparent from the drawings, the substrate coating apparatus of the prior art includes an application unit 200, a nozzle unit 100, and a pre-discharge unit 300 including an ultrasonic cleaning device.

The coating unit 200 includes a table 210 that is disposed on the base 400 with a bracket having a height adjustment mechanism as a medium and is formed with a plurality of through holes penetrating vertically; the base 400 and the table 210 can be lifted and lowered A plurality of horizontal plates 230 of thimbles 220 are provided.

The plurality of thimbles 220 are inserted into the through holes of the table 210, and as the horizontal plate 230 rises and falls, protrudes from the upper portion of the table 210 or retreats into the interior of the table 210. Thus, the plurality of thimbles 220 have the function of lifting the substrate from the table 210 or lowering the substrate.

At the same time, the left and right sides of the base 400, that is, on the left and right sides of the table 210, are provided with a pair of long guide rails 240 extending in the longitudinal direction. The pair of guide rails 240 are respectively provided with a transfer device 250 for longitudinal movement.

A nozzle unit 100 that sprays a coating agent such as a coating liquid onto the substrate 500 such as glass across the table 210 is applied between the pair of transfer devices 250. The slit nozzle 110 of the nozzle unit 100 has a bar shape extending in the lateral direction and is generally larger than the left and right widths of the substrate.

A fine discharge port 120 extending in the lateral direction is formed under the slit nozzle 110 to eject a coating liquid. A certain amount of the coating liquid can be ejected onto the substrate 500 via the linear ejection port 120.

Moreover, the transfer device 250 is in a state of supporting both sides of the nozzle portion 100. Next, it moves in the longitudinal direction at a certain speed, thereby moving the nozzle portion 100 on the table 210. At the same time, the transfer device 250 can adjust the height of the nozzle portion 100 in the vertical direction, and the distance between the output port 120 of the slit nozzle 110 and the substrate 500 can be finely controlled corresponding to the amount and viscosity of the coating liquid.

Further, the apparatus for supplying the coating liquid to the nozzle unit 100 includes a coating liquid supply unit 130 provided on the transfer device 250 side, and a first supply between the coating liquid supply unit 130 and the slit nozzle 110. The line 140; the second supply line 150 for supplying the coating liquid to the coating liquid supply unit 130 from an external supply source (not shown).

The coating liquid is supplied from the external supply source to the coating liquid supply unit 130 via the second supply line. The coating liquid supply unit 130 applies a predetermined pressure to the coating liquid by means of a pump provided inside the coating liquid so that the coating liquid is supplied from the first supply line 140 to the slit nozzle 110 at a predetermined pressure from the slit nozzle 110. The discharge port 120 is ejected.

A pre-discharging portion 300 is provided on the side of the coating portion 200. That is, the pre-discharge portion 300 is provided along the moving direction of the nozzle portion 100 and is located at the lower portion of the nozzle portion 100.

The preliminary output unit 300 is composed of a frame 310 and a precoat roller 320 located inside the frame 310.

However, as described above, the coating liquid supply unit 130 of the slit coater of the prior art is constituted by a cylinder and a pump (not shown) having a piston structure, and the pressurizing pump is vertically disposed at the upper portion of the base 400, If the environment is indoors, it will be restricted in space due to the height of the ceiling.

That is, the forward and reverse strokes of the piston will be limited by space, thus It is difficult to increase the capacity of the pressurizing pump.

Further, if the prior art pressure pump is unreasonably disposed in the horizontal direction, the air bubbles in the cylinder are shut off inside and cannot be discharged to the outside, thereby causing a problem of hardening the coating liquid, which eventually causes the use to be unusable. A serious problem with the entire pressurized pump.

Further, although the coating liquid supply unit 130 and the slit nozzle 110 are connected by the first supply line 140, the slit nozzle 110 is reciprocally transferred with respect to the fixed installation of the coating liquid supply unit 130, and thus is fixedly disposed. The first supply line 140 faces a lot of inconvenience, and since the transfer distance of the coating liquid exceeds the necessary distance, there is a problem that the coating liquid is delayed at the time of output.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a pressurizing pump for supplying a coating liquid in a horizontal direction in an upper portion of a slit nozzle.

In order to achieve the above object, a coating liquid supply device according to the present invention includes: a piston; a cylinder that forms a piston sliding portion that inserts the piston and reciprocates the piston in a horizontal direction, and is formed to slide on the piston The end of the portion expands the expansion portion of the space in the vertical direction.

Here, the piston sliding portion is connected to a supply valve for controlling the supply of the coating liquid, and an output valve for controlling the output of the coating liquid is connected to the lower end portion of the expansion pipe portion, and the center of the upper end portion of the expansion pipe portion is provided for A bubble discharge valve that discharges air bubbles inside the cylinder.

Moreover, the inner diameter of the piston sliding portion is larger than the outer diameter of the piston, thereby forming a gap between the piston sliding portion and the piston, via which the gap is formed for supply The coating liquid supply channel of the coating liquid.

Further, a ring-shaped sealing block surrounding the outer diameter of the piston is provided on the inner diameter surface of the piston sliding portion for guiding the reciprocating motion of the piston.

Here, a plurality of seal rings for maintaining airtightness are provided on the inner surface of the seal block that is in contact with the piston.

Moreover, the seal rings are provided in two or more, and the plurality of seal rings are disposed at a predetermined interval from each other.

A supply valve for receiving the coating liquid is connected to the piston sliding portion in front of the sealing block.

Here, the supply valve is closed during the forward stroke of the piston, the valve is open during the reverse stroke, and the valve is open during the forward stroke of the piston, and the valve is closed during the reverse stroke.

Further, the coating liquid on the storage tank side is pressed while the supply valve is opened to assist in filling.

The bubble discharge valve is opened at the forward stroke of the piston to discharge the air bubbles in the cylinder to the outside, and the output valve is maintained in the closed state while the bubble is being discharged.

Here, all the corners of the cylinder expansion portion are rounded.

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

Fig. 3 is a schematic view showing a slit coater using the coating liquid supply device of the present invention, and Fig. 4 is a cross-sectional view showing the internal structure of the coating liquid supply device of the present invention.

As shown in the figure, a coating liquid for a slit coater according to an embodiment of the present invention is provided. The device 3 is disposed on the upper side of the slit nozzle 4 in the horizontal direction. The coating liquid supply device 3 receives the coating liquid from the separately provided storage tank 5, and supplies a supply valve V1 that can control the supply of the coating liquid on the supply line.

Further, the slit nozzle 4 is provided on the upper portion of the base 1, and is reciprocated left and right by the transfer device, whereby the coating liquid is sprayed on the surface of the substrate (not shown) to form a coating layer.

The coating liquid supply device 3 of the present invention will be described in detail with reference to Fig. 4 . The coating liquid supply device 3 of the present invention comprises a cylinder 10 and a piston 20 inserted into the cylinder 10 to reciprocate.

The cylinder 10 forms a piston sliding portion 11 that is inserted into the piston 20 and reciprocates in the horizontal direction, and a pipe expanding portion 13 that expands the space in the vertical direction at the end of the piston sliding portion 11.

At this time, the inner diameter of the piston sliding portion 11 is larger than the outer diameter of the piston 20, thereby forming a gap (GAP) between the piston sliding portion 11 and the piston 20, thereby forming a coating liquid supply for supplying the coating liquid via the gap. Channel 12.

Further, a ring-shaped seal block 30 is provided inside the piston sliding portion 11 to stably support the reciprocating motion of the piston 20.

At this time, a plurality of seal rings 31 are provided on the inner surface of the seal block 30 which is in contact with the piston 20, whereby the ability to maintain airtightness can be improved. Moreover, the plurality of seal rings 31 may be disposed at a predetermined interval.

Here, before the sealing block 30 is disposed, the side side piston sliding portion 11 communicates with a supply line for receiving the coating liquid from the external storage tank 5, and the supply line is provided with a supply valve V1.

The supply valve V1 is closed when the piston 20 is in the forward stroke, and is alive. When the plug 20 is in the retracting stroke, the valve is open.

That is, when the piston 20 is in the forward stroke, the supply valve V1 is closed, and the coating liquid filled in the inside of the cylinder 10 is prevented from flowing back to the storage tank 5 side by the pressure of the piston 20, and in the reverse stroke of the piston 20, the supply valve V1 is supplied. Open, the coating liquid is supplied to the inside of the cylinder 10 for filling.

At this time, it is possible to supply a certain pressure to the coating liquid on the side of the storage tank 5 while opening the supply valve V1, thereby assisting the filling process. To this end, a pressure pump can be additionally provided on the side of the storage tank 5.

When the piston 20 is in the forward stroke, the coating liquid filled in the piston sliding portion 11 is sent to the expansion tube portion 13 side.

The expanded portion 13 has an inner space having a substantially rectangular cross-sectional shape, and an output valve V2 directly connected to the slit nozzle 4 is formed at the center of the lower end portion.

The output valve V2 is open when the piston 20 is in the forward stroke, and is closed when the piston 20 is in the reverse stroke.

That is, the output valve V2 is opened when the piston 20 is in the forward stroke, so that the coating liquid filled in the expanded portion 13 is supplied to the slit nozzle 4 side, and the output valve V2 is closed when the piston 20 is in the backward stroke, preventing the piston 20 from being closed. The coating liquid in the slit nozzle 4 is sucked into the cylinder 10 side by the vacuum pressure formed at the time of retreating.

Further, a bubble discharge valve V3 is formed at a central position of the upper end portion of the expanded portion 13, and the bubble discharge valve V3 is connected to the expanded portion 13 via a separately provided tube.

The bubble discharge valve V3 is opened as described above when the piston 20 is in the forward stroke, and the air bubbles inside the cylinder 10 are discharged to the outside.

At this time, when the additional pressure pump is used to assist the coating liquid to be filled in the cylinder 10 At this time, the pressure pump generates a positive pressure inside the cylinder 10, and in order to eliminate the positive pressure open bubble discharge valve V3, the air bubbles in the cylinder 10 are discharged to the outside.

When the bubble discharge valve V3 is opened, the discharge valve V2 is maintained in the closed state when the bubble exhaust is performed. After the bubble discharge is completed, the bubble discharge valve V3 is closed to open the output valve V2 to output the coating liquid.

At this time, the bubble discharge valve V3 must be provided at the upper end portion of the expanded portion 13, because the air bubbles inside the cylinder 10 are floated to the upper side by buoyancy.

Further, in order to prevent the air bubbles floating to the upper side from being caught at the corners of the expanded portion 13, the corners should be rounded 13a.

The coating liquid supply device of the slit coater provided by the present invention constructed as above is preferably disposed parallel to the upper portion of the slit nozzle 4, but may be disposed at a certain angle with the upper portion of the slit nozzle 4.

At this time, in order to minimize the transfer distance of the coating liquid when the coating liquid supply device is disposed obliquely, it is preferable that the expansion portion 13 side is disposed close to the upper surface of the slit nozzle 4.

The present invention having the above-described composition and function can be variously modified and modified by those skilled in the art using the various embodiments described above, and thus the technical scope of the present invention is not limited to the contents described in the specification, but should be patented. The scope is limited.

The present invention provides a pump for supplying a coating liquid in a horizontal direction in the upper portion of the slit nozzle, shortens the supply path of the coating liquid, and can solve the problem caused by the output delay, and can realize an increase in pump capacity, thereby improving the narrowness. The effect of the coater performance.

1‧‧‧Base

2‧‧‧Transfer device

3‧‧‧ Coating liquid supply device

4‧‧‧Slit nozzle

5‧‧‧ storage tank

10‧‧‧ cylinder

11‧‧‧Piston Sliding Department

12‧‧‧ Coating liquid supply channel

13‧‧‧Extension Department

13a‧‧‧ fillet

20‧‧‧Piston

30‧‧‧ Sealing block

31‧‧‧ Sealing ring

100‧‧‧Nozzle Department

110‧‧‧Slit nozzle

120‧‧‧ spout/outlet

130‧‧‧ Coating Liquid Supply Department

140‧‧‧1st supply line

150‧‧‧2nd supply line

200‧‧‧ Coating Department

210‧‧‧Table

220‧‧‧ thimble

230‧‧‧ horizontal board

240‧‧‧rail

250‧‧‧Transfer device

300‧‧‧Pre-ejection/prepared output

310‧‧‧Rack

320‧‧‧Pre-coated roller

400‧‧‧Base

500‧‧‧Substrate

V1‧‧‧ supply valve

V2‧‧‧ output valve

V3‧‧‧ bubble discharge valve

1 and 2 are side and perspective views of a substrate coating apparatus according to the prior art.

Fig. 3 is a schematic view of a slit coater using the coating liquid supply device of the present invention.

Fig. 4 is a cross-sectional view showing the internal structure of the coating liquid supply device of the present invention.

1‧‧‧Base

2‧‧‧Transfer device

3‧‧‧ Coating liquid supply device

4‧‧‧Slit nozzle

5‧‧‧ storage tank

V1‧‧‧ supply valve

V3‧‧‧ bubble discharge valve

Claims (8)

A coating liquid supply device for a slit coater, comprising: a piston; a cylinder that forms a piston sliding portion that inserts the piston and reciprocates the piston in a horizontal direction, and is formed on the piston The end portion of the sliding portion expands the space in the up-and-down direction; wherein a ring-shaped sealing block surrounding the outer diameter of the piston is disposed on the inner diameter surface of the piston sliding portion for guiding the reciprocating movement of the piston. The coating liquid supply device of the slit coater of claim 1, wherein a plurality of seal rings for maintaining airtightness are provided on an inner surface of the seal block that is in contact with the piston. The coating liquid supply device of the slit coater of claim 2, wherein the plurality of seal rings are disposed at a predetermined interval from each other. The coating liquid supply device of the slit coater of claim 2, wherein a supply valve for receiving the coating liquid is connected to the piston sliding portion in front of the sealing block. The coating liquid supply device of the slit coater of claim 1, wherein the piston sliding portion is connected to a supply valve for controlling supply of the coating liquid, and the lower end portion of the expanded portion is connected for controlling coating a liquid output output valve in which a bubble discharge valve for discharging air bubbles inside the cylinder is disposed at a center of an upper end portion of the expansion pipe portion; and wherein the bubble discharge valve is opened at a forward stroke of the piston to discharge air bubbles in the cylinder to the outside. Output valve dimension during bubble discharge Closed. The coating liquid supply device of the slit coater of claim 5, wherein the supply valve is closed during the forward stroke of the piston, the valve is opened during the reverse stroke, and the valve is open during the forward stroke of the piston The valve closes during the retraction stroke. The coating liquid supply device of the slit coater of claim 6, wherein the coating liquid on the storage tank side is pressurized while the supply valve is opened to assist in filling. The coating liquid supply device of the slit coater of claim 1, wherein an inner diameter of the piston sliding portion is larger than an outer diameter of the piston, thereby forming a gap between the piston sliding portion and the piston, forming a gap through the gap a coating liquid supply passage for supplying a coating liquid; and wherein the corners of the cylinder expansion portion are all rounded.