JPH04123529U - Rotary coating device - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent a decrease in the exhaust volume of an exhaust pipe in an apparatus that spin-coats a chemical solution such as a resist onto a wafer. Structure: A means for applying a chemical solution such as a resist 20 to a wafer to be processed 12 by rotation is provided in the center of the cup 10, and an exhaust pipe such as an exhaust hose 26 is connected to the bottom of the cup 10. A filter device 28 with a replaceable filter element is provided near the inlet of the exhaust pipe, and the filter element filters exhaust gas during spin coating to suppress discharge of chemical mist. As a result, the amount of chemical mist adhering to the inner wall of the exhaust pipe is reduced, and by appropriately replacing the filter element, it is possible to prevent a decrease in the exhaust volume. Further, the filter element may be replaced automatically by detecting the degree of contamination of the filter element using the anemometer 30 or the like.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This idea was developed to improve the equipment for spin-coating chemical solutions such as resist onto wafers. A filter means with a replaceable filter element is installed in the exhaust pipe connected to the processing container. This makes it possible to prevent a decrease in displacement.

0002

[Conventional technology]

Conventionally, in semiconductor device manufacturing processes, resist, SOG (spin-on Rotary coating for applying chemical solutions such as glass) and polyimide to the surface of semiconductor wafers. The device is widely used. This type of rotary coating device has a cup-shaped A chemical solution is applied to the top of the wafer while the semiconductor wafer is held flat in the processing container. After dropping the wafer, the wafer is rotated at high speed to cause the dropped chemical solution to wafer by centrifugal force. It is known to form a coating film by spreading it toward the outer circumference of the wafer.

0003 Such spin coating equipment produces a mist made up of fine particles of chemical liquid during spin coating. occurs around the wafer. Chemical mist slows down the evaporation rate of the solvent in the dropped chemical. This may reduce the thickness of the coating film, or it may adhere to the coating film and deteriorate the film quality. , is harmful. Therefore, in the past, an exhaust hose was connected to the bottom of the processing container. Chemical mist was discharged through this hose.

0004

[Problem that the idea aims to solve]

According to the conventional rotary coating device mentioned above, after repeating the coating process several times, As the amount of chemical mist that adheres to the inner wall of the exhaust hose gradually increases, the exhaust volume decreases. This has the disadvantage of causing uneven thickness and deterioration of the film quality of the coating film.

[0005] The purpose of this invention is to develop a new rotary coating device that can prevent a decrease in displacement. Our goal is to provide the following.

[0006]

[Means to solve the problem]

The spin coating device based on this idea is (a) a cup-shaped processing container; (b) An applicator installed in this processing container that spin-coats the chemical onto the wafer to be processed. step by step, (c) an exhaust arrangement connected to the bottom of the processing container to discharge the mist of the chemical solution; tube and (d) filter means with a replaceable filter element, the filter element being Placed at or near the entrance of the exhaust pipe to suppress the discharge of mist of the medicinal solution. what is being done It is equipped with the following.

[0007] In such a configuration, for example, it is possible to measure the exhaust flow state (wind speed, air volume, etc.). a detection means for detecting the degree of contamination of the filter element by, for example, detecting the degree of contamination of the filter element; Determine whether the detected degree of contamination exceeds a predetermined limit level, and if it exceeds the level, the filter control means for controlling said filter means to replace the filter element with a new one; It's okay.

[0008]

[Effect]

According to the configuration of this invention, the filter element is installed at the inlet of the exhaust pipe or in the vicinity thereof. This design prevents chemical mist from adhering to the inner wall of the exhaust piping. This reduces the amount of chemical mist that is produced, and by replacing the filter element as appropriate, you can prevent a drop in exhaust volume. Can be stopped.

[0009] In addition, if the detection means and control means are provided as described above, it is possible to replace the filter element. can be done automatically.

0010

【Example】

FIG. 1 shows a spin coating device according to an embodiment of this invention, and this device has the following features: The exhaust piping is equipped with a filter device that allows the filter element to be replaced by operating a switch. It is characterized by this.

[0011] In FIG. 1, a wafer 12 to be processed, such as a semiconductor wafer, is placed in the center of the cup 10. A chuck 14 for suctioning and holding the wafer 12 is provided, and the chuck 14 holds the wafer 12 flat. It is designed to be driven by a motor 16 so that it rotates while being held in place. . The dropping nozzle 18 is used to drop a chemical solution such as the resist 20 onto the upper surface of the wafer 12. It is movable between the dripping position shown in FIG. 1 and the standby position outside the cup 10. It is set in.

0012 The bottom surface of the cup 10 is provided with an exhaust hole below the chuck 14 so as to surround the chuck 14. A liquid blocking plate 22A is provided. The bottom of the cup 10 is lower on one side than on the other. The lower bottom part has a drainage hole for discharging the drainage liquid LQ. A base 24 is provided, and an exhaust hose 2 for leading out the exhaust gas is provided at the higher bottom. 6 is provided. On the bottom of the cup 10, near the attachment part of the hose 24, A drainage blocking plate 22B is provided to prevent drainage from entering the chuck 14 side. In addition, the drain liquid enters the hose 26 and the chuck 14 near the attachment part of the hose 26. A drainage blocking plate 22C is provided to prevent this.

[0013] A filter device 28 is installed near the inlet of the exhaust hose 26 (near the cup). I'm being kicked. In the filter device 28, from the supply reel R1 to the take-up reel R A plurality of filter elements F are arranged side by side in the winding direction on a long and narrow sheet that is wound up into The take-up reel R2 is driven by a motor M. initial state Now, the filter element F is set across the hose 26. And the switch When the SW is turned on, the take-up reel R2 is driven by the motor M and the next filter is required. The element is set across the hose 26. After this, turn on the switch SW in the same way. The filter element is replaced each time the filter is turned on. Each filter element separates the exhaust from the Configured to remove liquid mist. Note that the outlet of the exhaust hose 26 is the factory exhaust. (not shown).

[0014] For example, in the case of spin coating a resist, the dripping nozzle 18 is Then, a required amount of resist 20 is dropped onto the wafer 12. And the drip nozzle 18 After returning the wafer to the standby position outside the cup 10, start the motor 16 and place the wafer 12. Rotate at high speed in a fixed direction. As a result, the resist 20 extends far to the outer circumference of the wafer 12. It spreads due to mental force, and a resist coating film is formed on the wafer 12. After this, The wafer 12 can be removed from the chuck 14 and moved on to the next baking process, etc. Ru.

[0015] During the spin coating process, the resist mist will be exhausted through the exhaust hose 26. , most of which is captured by filter element F. For this reason, the hose 26 Resist attached to the section from the location of the filter element F to the outlet inside The amount of mist is significantly reduced.

[0016] Filter element F becomes contaminated as the coating process is repeated several times, but as mentioned above, If you turn on the switch SW as shown above, you can replace the filter element F with a new one. I can do it. Therefore, it is possible to prevent a decrease in the displacement amount and clogging of the pipes.

[0017] In the embodiment of FIG. 1, instead of replacing the filter element by operating a switch, the filter element is rotated. A configuration in which the filter element is changed by driving the reel by operating a handle that is possible; Or, when a new filter element is inserted, the old filter element is expelled. may be used.

[0018] FIG. 2 shows a spin coating device according to another embodiment of this invention, which is similar to FIG. 1. The same reference numerals are given to the parts, and the detailed explanation will be omitted.

[0019] The embodiment of FIG. 2 is characterized by providing an anemometer 30 and a filter control device 32 to The filter element exchange in the filter device 28 is automatically performed. sand That is, an anemometer 30 is provided in the vicinity of the cup of the exhaust hose 26 to measure the wind speed inside the hose. Detect. The anemometer 30 is installed in the exhaust passage inside the cup 10 as shown by the broken line 30a. You can leave it. The wind speed signal from the anemometer 30 is supplied to a filter controller 32; Used to determine whether the degree of contamination of filter element F exceeds a predetermined limit level . For example, when the wind speed value falls below a predetermined value, it means that the degree of pollution has exceeded the limit level. , and a determination output pulse to that effect is sent from the filter control device 32 to the filter device 28. supplied to

[0020] The filter device 28 responds to the determination output pulse from the filter control device 32. Then, the filter element replacement operation is performed in the same manner as when the switch SW is turned on. This conclusion As a result, the same effect as in the embodiment shown in Fig. 1 can be obtained to prevent the reduction in displacement, and there is no need for replacement operations. There are also benefits such as no defects occurring due to forgotten operations.

[0021] In the embodiment shown in FIG. 2, the filter element Instead of detecting the degree of contamination, it is possible to detect the degree of contamination from the degree of reflection or transmission of light irradiated onto the filter element A configuration for detecting the degree of contamination can also be adopted. Further, as the filter device 28, a filter device 28 may be used. The old filter element is ejected every time a judgment output pulse is received from the router controller 32. A type that also sets a new filter element may also be used.

[0022] The spin coating device of this invention can be used not only for resists but also for SOG, polyimide, etc. It can also be used for coating. In addition, the wafers to be processed are limited to semiconductor wafers. First, a mask substrate or the like can also be used.

[0023]

[Effect of the idea]

As described above, according to this invention, the By replacing the filter element, the reduction in exhaust volume was prevented, so the coating film was This provides the effect of improving thickness uniformity and film quality.

[0024] Moreover, automating the replacement of filter elements reduces the burden on workers and eliminates manual intervention. It also has the effect of avoiding mistakes.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a spin coating device according to an embodiment of the invention.

FIG. 2 is a sectional view showing another embodiment of the invention.

[Explanation of symbols]

10: Cup, 12: Wafer to be processed, 14: Chuck,
16: Motor, 18: Dripping nozzle, 20: Resist, 2
2A to 22C: Drainage prevention plate, 24: Drainage hose, 26:
Exhaust hose, 28: Filter device, 30: Anemometer, 3
2: Filter control device.

Claims (2)

[Scope of utility model registration request] 1. (a) a cup-shaped processing container; (b) a coating means provided in the processing container for spin-coating a chemical onto a wafer to be processed; and (c) a device for discharging a mist of the chemical. an exhaust pipe connected to the bottom of the processing container; and (d) a filter means with a replaceable filter element, the filter element being at or near the entrance of the exhaust pipe to suppress discharge of the chemical mist. A rotary coating device with a part placed on the part. 2. (a) a cup-shaped processing container; (b) a coating means provided in the processing container for spin-coating a chemical onto a wafer to be processed; and (c) a device for discharging a mist of the chemical. an exhaust pipe connected to the bottom of the processing container; and (d) a filter means with a replaceable filter element, the filter element being at or near the entrance of the exhaust pipe to suppress discharge of the chemical mist. (e) detection means for detecting the degree of contamination of the filter element; and (f) determining whether the degree of contamination detected by the detection means exceeds a predetermined limit level; and control means for controlling said filter means in order to replace said filter element with a new one.