JPH03293056A - Coating apparatus - Google Patents

Abstract

PURPOSE:To improve the yield of coated product by covering the upper open surfaces of an inner cup and an outer cup whose lower surfaces are closed and upper faces are opened with cover bodies freely openable and closeable. CONSTITUTION:The outer cup 23 receiving drain from the inner cup 22 revolved with a spinner is disposed at the outside of the inner cup 22. The inner cup 22 and the outer cup 23 are closed at their lower surfaces and opened at their upper surfaces, and the opened upper surfaces of cups 22, 23 are covered with the cover body 36 which is freely opened and closed. Thus, the coating liquid recovered temporarily in the outer cup is prevented from being scattered to the outside and floating in the air. Consequently, when the cover body is opened to take out the treated thing W, for example, the powder solidified of the coating liquid floating in the air is prevented from sticking to the surface of treated thing, and the production of defective things is prevented, so that the yield is sharply improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a coating device used in the manufacturing process of liquid crystal displays (LCDs) and the like.

(Prior Art) Liquid crystal displays are attracting attention as a display device that can replace cathode ray tubes (CRTs).

A liquid crystal display has a structure in which liquid crystal is injected between two glass substrates on which electrodes and elements constituting pixels are formed. Each pixel is then connected to a thin film transistor (T P
Active matrix systems driven by elements such as T) and metal/insulator/metal junctions (MIM) are becoming mainstream because they provide high-quality screens.

The technique for forming the above-mentioned thin film transistor on a glass substrate is a direct application of the semiconductor manufacturing technique for forming an integrated circuit on a silicon wafer or the like. Coating the resist solution is also one of a series of steps, and in this step, the glass substrate is set on a vacuum chuck inside the inner cup.
The resist solution is dropped onto the glass substrate, and then the vacuum chuck and the inner cup are rotated together by a spinner to uniformly apply the resist solution to the surface of the glass substrate using centrifugal force.

A portion of the dropped coating liquid is then scattered onto the inner wall of the inner cup due to centrifugal force. If this coating liquid is left as it is, it will dry and solidify, forming small pieces that will adhere to the surface of the object to be treated.

To prevent this, conventionally a drain vibrator is attached to the outer peripheral wall of the inner cup, and excess coating liquid is discharged into the outer cup via the drain vibrator.

(Problem to be Solved by the Invention) As described above, in the conventional coating device, since the non-rotating outer cup is disposed close to the outside of the rotating inner cup, the inner cup and outer cup are separated. A turbulent flow occurs between the two, and the coating liquid collected in the outer cup is sucked outside and becomes suspended in the form of mist, and particles of the floating coating liquid adhere to the surface of the workpiece. This causes spot defects.

Particularly in the manufacture of liquid crystal displays, a large number of transistors are embedded on a glass substrate (5 transistors per square centimeter).
0 or more transistors), and even if one of these transistors is defective, the entire board is considered defective. This is a decisive difference in yield between the manufacture of active matrix liquid crystal displays and the manufacture of semiconductors such as LSI.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a coating device in which an outer cup for receiving drain from the inner cup is disposed outside an inner cup rotated by a spinner. Not only the top surface but also the open top surface of the outer cup is covered with a lid body that can be opened and closed.

(Function) A plate-shaped object to be processed, such as a glass substrate, is set on the vacuum chuck in the inner cup, and the coating liquid is dripped onto the surface of this plate-shaped object, and then the upper surface of the inner cup and the upper surface of the outer cup are attached to the lid. The vacuum chuck and inner cup are rotated together in the closed state, and the coating liquid dropped onto the surface of the plate-shaped object is uniformly dispersed.

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

Fig. 1 is a plan view of a film forming line incorporating the coating device according to the present invention, Fig. 2 is a sectional view of the coating device with the lid lifted, and Fig. 3 is a cross-sectional view of the coating device with the lid closed. 1, the film forming line is provided with an input part 1 for a plate-shaped workpiece W such as a glass substrate at the most upstream part (the left end in FIG. 1), and the film forming line according to the present invention Coating device 2 related to
A heating section 5 equipped with a vacuum drying device 3, a back cleaning bag Wt4 for the workpiece W, and a hot plate 5a, etc. is arranged downstream of the coating device 2 in order, and heating is carried out from the input section 1. Up to the heating section 5, the workpiece W is transported with the lower surfaces of the front and rear ends supported by the transport device 6, and in the heating section 5, the transport device makes a crank movement within a vertical plane! ! Each hot plate 5a is in a state where the lower surface of the workpiece W is supported by
The workpiece W is conveyed while the top is transferred one after another.

Next, details of the coating device 2 will be explained based on FIGS. 2 and 3.

The coating device 2 has an outer cup 23 fixed to the outside of an inner cup 22 attached to a shaft 21 of the spinner device. These inner cup 22 and outer cup 23 have their lower surfaces closed and their upper surfaces opened, and the inner cup 22
A vacuum chuck 24 for suctioning and fixing the workpiece W is provided at the center of the inner cup 22, and a drain vibrator 25 is attached to the lower side wall of the inner cup 22. Further, a drain recovery ring 26 is arranged inside the outer cup 23. This drain recovery ring 26 has an inner wall lower than an outer wall so that the tip of the train vibe 25 is exposed, and a bottom wall inclined to one side, and a drain recovery vibe 27 is attached at the lowest position. Further, an exhaust port 28 is formed in the closed lower surface of the outer cup 23.

On the other hand, arms 29 and 30 are arranged above the inner cup 22 and the outer cup 23, as shown in FIG. These arms 29 and 30 are capable of linear movement, rotational movement, vertical movement, or a combination of these movements, and are designed not to interfere with each other.

A nozzle for dispensing a coating liquid such as a resist liquid is attached to the arm 29, and a shaft 31 extending downward is attached to the tip of the arm 30, and a boss portion 34 is attached to this shaft 31 via a bearing 32 and a magnetic seal 33. A disc-shaped aluminum lid 35 is attached to the boss portion 34 so as to be rotatably fitted therein and for closing the upper opening of the inner cup 22 . Moreover, the arm 3 above this lid body 35
A lid 36 for closing the upper opening of the outer cup 23 is fixed to the lower surface of the tip of the outer cup 23.

Further, a nozzle hole 37 is bored in the shaft 31, and this nozzle hole 37 is connected to a source of pressurized air such as nitrogen gas via a joint 38.

On the other hand, a rectifier plate 40 is attached to the lower surface of the lid body 35 by a screw 39.
is installed. The outer diameter of the current plate 40 is slightly smaller than the inner diameter of the inner cup 22, and the nozzle hole 37 opens in a space formed between the lower surface of the lid 35 and the upper surface of the current plate 40.

In the above, in order to uniformly apply the resist liquid to the surface of the workpiece W such as a glass substrate, the upper surfaces of the inner cup 22 and the outer cup 23 are opened and the workpiece W fixed on the vacuum chuck 24 is opened. A resist liquid is dripped onto the surface from a nozzle attached to the arm 29, and then the arm 29 is moved back and the arm 30 is rotated over the inner cup 22 and outer cup 23 as shown in FIG. .36 is coming. Then, as shown in FIG. 3, by lowering the arm 30, the upper surface of the inner cup 22 is closed with the lid 35, and the upper surface opening of the outer cup 23 is closed with the lid 36, and then the spinner is used to remove the vacuum chuck. The inner cup 22 is rotated integrally, and the resist liquid is applied to the object W by centrifugal force.
Spread evenly over the surface.

In the above process, the inside of the inner cup 22 is in a reduced pressure state, so in order to take out the object W to be processed evenly coated with the resist liquid, first the cover body 35 and the rectifying plate 4 are removed through the nozzle hole 37. This is done by introducing nitrogen gas or the like into the space between them to release the reduced pressure state. At this time, the gas from the nozzle hole 37 is not directly blown onto the resist liquid on the surface of the object W because of the rectifying plate 40 .

In the embodiment, the lid 36 that closes the opening of the outer cup is attached to the lower surface of the tip of the arm 30, but it may be attached to a member other than the arm 3o.

(Effects) As explained above, according to the present invention, since the inner cup is rotated with the top openings of the inner cup and outer cup of the coating device being closed with the lid, the inner cup is temporarily collected in the outer cup. This prevents the applied liquid from turning into a mist and scattering and floating outside. Therefore, when the lid is opened and the workpiece is taken out after coating, the solidified powder of the coating liquid floating in the air can be prevented from adhering to the workpiece surface, resulting in defective products, and the yield can be improved. Significantly improved.

[Brief explanation of drawings]

Fig. 1 is a plan view of a film forming line incorporating the coating device according to the present invention, Fig. 2 is a sectional view of the coating device with the lid lifted, and Fig. 3 is a top view of the coating device with the lid lifted. It is a sectional view of a closed state. In the drawing, 1 is a film forming line, 2 is a coating device, 22 is an inner cup, 23 is an outer cup, 35, 36 is a lid body, 37 is a nozzle hole, 40 is a rectifier plate, and W is a plate-shaped object to be treated. be. Patent Applications Same Attorneys Same Patent Attorneys Same Patent Attorneys Tokyo Ohka Kogyo Co., Ltd. Tatsumo Co., Ltd. 1) Yoshibetsu Ohashi Kunihiko Koyama Yu

Claims (1)

[Claims] In a coating device in which an outer cup for receiving drain from the inner cup is arranged outside an inner cup rotated by a spinner, the inner cup and the outer cup close the lower surface and open the upper surface, and the inner cup and the outer cup are opened. A coating device characterized in that the top surface of the coated coating is covered with a lid body that can be opened and closed.