JP2002239443A - Spin coater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently discharge air and mist while more stably controlling the operation. SOLUTION: When a spin table 3 is rotated at the time of forming a thin film on a substrate 2, a blade 14 is rotated synchronously with the rotation of the spin table 3 to more reduce the number of rotation as compared to that of the spin table 3 and the downward flow of air is generated by the rotation of the blade 14. The air flowing in a spin cap 6 or the mist of an excess coating liquid moves forcibly under the blade 14 by the air flow to avoid the substrata 2 on the spin table 3. As a result, it is suppressed that the coating liquid R at the time of forming the thin film on the substrate 2 is affected by the air, and the thickness of the formed thin film is more uniformized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a thin film forming apparatus for forming a thin film on a substrate of, for example, a semiconductor, a liquid crystal, a DVD, or the like. It belongs to the technical field of a spin coater that forms a thin film on a substrate by spreading a liquid by centrifugal force.

[0002]

2. Description of the Related Art One of the methods for forming a thin film on a substrate of a semiconductor, a liquid crystal, a DVD or the like is a spin coating method. After that, a spin coater is used to form a thin film on the substrate by rotating the substrate and spreading the coating liquid by centrifugal force.

FIG. 3 is a diagram schematically showing an example of such a conventional spin coater. In the figure, 1 is a spin coater, 2 is a substrate such as a silicon wafer, a glass substrate, or a substrate disk on which a thin film is formed. 3 is a spin table for supporting and rotating the substrate 2 on the upper surface (a support table of the present invention). 4 is a spin motor (M) composed of a servo motor for rotating the spin table 3 (corresponding to the driving means of the present invention). 5 is a rotating shaft 3a of the spin table 3 connected to a rotating shaft of the spin motor 4. , A spin cup (corresponding to the container of the present invention) for accommodating the spin table 3, a vacuum generating means 7, and an air or mist inside the spin cup 6 flowing to be discharged to the outside. An exhaust duct (corresponding to the exhaust passage of the present invention), 9 is a fan, and 10 is a flow control device such as a manometer.

[0004] In this conventional spin coater 1,
In forming a thin film on the substrate 2, the substrate 2 is suction-held on the spin table 3 by the vacuum from the vacuum generating means 7. Next, a predetermined amount of the coating liquid R is dropped onto a predetermined area including the center of the substrate 2 by a coating liquid supply unit (not shown). Next, the spin motor 4
Is driven to rotate the spin table 3 and the substrate 2 integrally at a predetermined rotation speed (generally, about 8000 rpm), the coating liquid dropped on the substrate 2 spreads on the substrate 2 by centrifugal force. . When the coating liquid has spread over the entire surface of the substrate 2, the spin motor 4 is stopped to stop the rotation of the spin table 3 and the substrate 2, whereby a thin film of the coating liquid is formed on the surface of the substrate 2.

In the thin film formation by the spin coating method, the thickness (thickness) of the thin film is controlled by controlling the centrifugal force, that is, by controlling the rotation speed of the spin motor 4. That is, various desired film thicknesses are obtained by variously changing the setting of the rotation speed of the spin motor 4 based on the viscosity (viscosity) of the coating liquid. The time required to perform this thin film formation processing varies slightly depending on the size of the substrate, the type of the substrate, and the like, but is on average about 30 seconds. In addition, conventionally, the substrate 2 and the like are cleaned using a spin coater, and a cleaning process of cleaning, rinsing, and drying is also performed.

The spin table 3 is housed in a spin cup 6 so that the coating liquid R spreading by centrifugal force does not leak to the outside. The space is large, and the upper part of the spin cup 6 is largely open. On the other hand, when the substrate 2 is rotated to generate centrifugal force, wind is generated at the same time. This wind is generated as the size of the substrate 2 increases or the rotation speed of the substrate 2 (that is, the rotation speed of the spin table 3). And motor M4
Rotation speed) The rotation speed increases. When the wind is generated in this manner, the wind causes the air to flow into the spin cup 6 from above as shown by arrows in FIG.
Since the air flowing into the spin cup 6 comes into contact with the coating liquid on the substrate 2, the coating liquid R is partially dried and hardly spread on the substrate 2,
A thin film having a uniform thickness will not be formed.

Therefore, conventionally, the air flowing into the spin cup 6 is forcibly exhausted to the outside through the exhaust duct 8 by the fan 9 so that the flowing air does not touch the coating liquid on the substrate 2 as much as possible. The wind flow is directed to the outside of the outer periphery of the substrate 2. In the forced evacuation by the fan 9, the surplus coating liquid dropped from the substrate 2 is drained together with the air exhaust. At the time of cleaning, the cleaning liquid is similarly drained by the fan 9. At this time, the amount of air exhausted and the amount of drainage of the coating liquid R and the cleaning liquid are controlled by the flow rate control device 10 independently of the rotation speed control of the substrate 2.

[0008]

However, the size of the substrate 2 currently manufactured is, for example, a silicon wafer having a diameter of, for example, about 300 φ (mm), and a glass substrate having, for example, a length and width of 650 □ (mm). X thickness 0.7m
There are various settings, such as at the m-th place. For this reason, the peripheral speed at the outer peripheral end of the substrate 2 greatly varies depending on the size of the substrate 2. In particular, when the size of the substrate 2 increases, the spin of the substrate 2 rotates at a high speed, and the fluctuation of the peripheral speed of the substrate 2 further increases. Further, as described above, the time required for the thin film forming process is about 30 seconds on average, but since the size of the substrate 2 is variously set, the spin time required for forming the thin film is also various. It will be various.

As described above, the size of the substrate 2 varies, the spin of the substrate rotates at a high speed,
If the peripheral speed fluctuates greatly, or if the spin time required to form a thin film is various, the control of the rotation of the substrate 2 and the control of the exhaust and drain are performed independently as described above. In addition, the control of the exhaust and the drain becomes delicate and difficult to control the rotation of the substrate 2, and these controls become unstable.

[0010] As shown in FIG.
Since the distance from the inside to the fan 9 is relatively long and the pipe resistance is large due to the sudden change in the pipe shape, etc., even if the exhaust amount of air by the flow control device 10 is maximized and the rotation speed of the fan 9 is increased, The amount of air exhausted through the exhaust duct 8 and the amount of mist such as a coating liquid or a cleaning liquid drained are limited. In particular, substrate 2
In the case of the high-speed rotation, the discharge amount through the exhaust duct 8 is further restricted. In the conventional spin coater 1, the air and mist in the spin cup 6 are sucked through the long exhaust duct 8 by the fan 9, so that the air and the mist are exhausted through the exhaust duct 8. Drainage is difficult to be performed effectively, resulting in poor exhaust efficiency and drain efficiency.

Further, since the exhaust efficiency and drain efficiency are poor, the amount of air and mist in the spin cup 6 sent to the exhaust duct 8 is reduced by the amount of air exhausted through the exhaust duct 8 and the amount of mist drained. As shown in FIG. 4, air and mist stay in the spin cup 6, and the pressure inside the spin cup 6 may be increased to a high pressure. In particular, when the substrate 2 is rotated at a high speed, the pressure inside the spin cup 6 is more likely to be increased, resulting in a high pressure. Therefore, spin cup 6
The mist that hits the inner wall of the spin cup 6 flows back and adheres again to the substrate 2, and a uniform film thickness cannot be obtained, or the mist in the spin cup 6 flows back as indicated by an arrow in FIG. In some cases, the liquid was ejected from the upper opening of the spin cup 6 to the outside.

As described above, the control of the exhaust of air and the drain of the mist are unstable, and if the exhaust efficiency and the drain efficiency are poor, the thin film formed on the substrate 2 is affected by the wind generated at the time of forming the thin film. In other words, the amount of air flowing into the spin cup 6 that hits the thin film forming portion of the substrate 2 increases due to this wind.
It is difficult to make the thickness of the formed thin film even more uniform.

The present invention has been made in view of such a problem, and an object of the present invention is to efficiently and stably and at least control the discharge of air and mist from the upper surface region of a substrate. By doing so
An object of the present invention is to provide a spin coater that can make the thickness of a thin film even more uniform.

[0014]

According to a first aspect of the present invention, there is provided a support table for supporting a substrate, which is accommodated in a container and to which a coating liquid is applied, on an upper surface, and comprising: A spin coater having at least a rotating drive means and a discharge passage provided below the support table to discharge at least one of air and mist in the container to the outside of the container; And a blade for generating an airflow directed downward from the support table by rotating in synchronization with the support table.

Further, the invention according to claim 2 is characterized in that the blades are arranged outside the outer periphery of the support table. Further, the invention according to claim 3 is characterized in that the blade is provided integrally on the outer periphery of the support table.

Further, the invention according to claim 4 is characterized in that the blades are formed separately from the support table, and are provided below the support table and coaxially with the support table. I have. Further, claim 5
The present invention is characterized in that a speed reduction mechanism for rotating the blade at a lower speed than the rotation speed of the support table is provided. Further, the invention of claim 6 is characterized in that the speed reduction mechanism is constituted by a planetary gear mechanism.

[0017]

In the spin coater according to the present invention having the above-described structure, when the support table is rotated by the driving means, wind is generated in the container as in the conventional case, and air flows from the upper opening of the container into the container. Flows into. At this time, the blades provided in the container rotate in synchronization with the rotation of the support table, and the rotation of the blades generates an airflow directed outward from the outer periphery of the support table and below the support table. Then, the air flowing into the container is effectively guided to the outside of the outer periphery of the support table by this air flow, and the air flowing toward the substrate on the support table is much reduced as compared with the related art.

This reduces the amount of air flowing into the container that hits the coating liquid on the substrate, so that the coating liquid that is forming a thin film on the substrate is hardly affected by the air, and the formed thin film is thin. Has a more uniform film thickness. In particular, the blades rotate synchronously with the substrate and the support table so that when forming a thin film, the blades rotate according to the substrate rotation speed conditions set according to various sizes and various shapes of the substrate. Therefore, the generated airflow also corresponds to the rotation speed condition of the substrate. Therefore, the forced air flow by the blades can be easily controlled according to the rotation speed of the substrate on which the thin film is formed, that is, the type of the substrate, the thickness of the thin film, and the like. This also allows a thin film having a more uniform thickness to be formed. Air or mist forcedly flowing to the inlet of the exhaust passage by the blades flows into the exhaust passage, and is discharged to the outside of the container through the exhaust passage.

By the way, due to the forced flow of air downward from the support table by the blades, a high pressure does not occur in the region upstream of the blades in the container, that is, in the region where the upper surface of the support table and the substrate are located. As a result, the mist of the surplus coating liquid flowing out from the substrate does not flow upward due to backflow as in the conventional case, so that the uniformity of the film thickness of the formed thin film hardly adheres to the substrate. In addition to the further improvement, it is possible to more reliably suppress the ejection from the upper opening of the container to the outside.

In particular, according to the second aspect of the present invention, since the blades are arranged outside the outer periphery of the support table, the air flowing into the container from the upper opening of the container is more effective outside the outer periphery of the support table. And the air flowing toward the substrate on the support table is suppressed. Thereby, the influence of air on the coating liquid is further reduced.

According to the third aspect of the present invention, since the blades are provided integrally on the outer periphery of the support table, the structure is simplified and the number of parts is reduced accordingly. Furthermore, in the invention of claim 4, since the blade is formed separately from the support table, the rotation speed of the blade can be controlled independently of the rotation speed of the support table. Further, according to the fifth aspect of the present invention, the blade is rotated at a lower speed than the rotation speed of the support table by the speed reduction mechanism. Thus, even if the blades are provided outside the outer periphery of the support table and the moment of inertia increases, the rotation speed control of the blades is simplified.

Further, according to the invention of claim 6, since the speed reduction mechanism is constituted by a planetary gear mechanism, the speed reduction mechanism can be arranged inside a blade provided outside the outer periphery of the support table, so that the apparatus is compact. Is formed. In particular, when the planetary gear mechanism is formed of resin, the device is formed to be lightweight and compact, and the generation of noise is prevented.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram schematically illustrating an example of an embodiment of a spin coater according to the present invention. The same components as those of the conventional spin coater shown in FIG. 3 described above are denoted by the same reference numerals, and a detailed description thereof will be omitted.

As shown in FIG. 1, in the spin coater 1 of this embodiment, a sun gear 11 made of resin is provided on a rotating shaft 3a between a spin table 3 and a bearing 5 in a container 6, and a rotating shaft 3a.
It is attached so that it can rotate together with it. This sun gear 1
A predetermined number (two in the illustrated example) of resin-made planetary gears 12 mesh with each other at equal intervals in the circumferential direction, and these sun gears 11 are provided on the spin cup 6 so that they can only rotate. Further, a ring-shaped resin internal gear 13 meshes with each planetary gear 12, and this internal gear 13 is arranged coaxially with the rotating shaft 3a, and is rotatable with the spin cup 6 by a bearing or the like. And supported by the spin table 3 so as to be rotatable relative to the spin table 3. The internal gear 13 does not necessarily need to be supported by the spin table 3, but may be rotatably supported only by the spin cup 6, for example.

A ring-shaped resin blade 14 is provided integrally on the outer periphery of the internal gear 13, and is rotatable integrally with the blade 14. In this case, the blades 14 are provided inside the spin cup 6 outside the outer periphery of the spin table 3, and a gap between the outer peripheral edge of the blades 14 and the inner wall of the spin cup 6 is formed with the blades 14. It is set as small as possible so as not to interfere with the inner wall of the spin cup 6.

The shape of the blade 14 is higher than the blade 14 when the substrate 2 and the support table 2 are rotated in a direction opposite to the rotation of the spin direction shown in FIG.
The shape is set such that the air in the spin cup 6 on the side of the spin table 3 generates an airflow flowing below the blades 14, that is, toward the exhaust duct 8. The other configuration of the spin coater 1 of this example is the same as the conventional example shown in FIG.

In the spin coater 1 of this embodiment having the above-described structure, the spin motor 4 is used to spread the coating liquid R dropped on the substrate 2 by centrifugal force when forming a thin film, similarly to the above-mentioned conventional example. Drives the spin table 3 and the substrate 2 at a predetermined number of revolutions in the illustrated spin direction via the rotation shaft 3a. At this time, the sun gear 11 integrated with the rotating shaft 3a rotates in the same spin direction and at the same rotational speed. By the rotation of the sun gear 11, each of the planetary gears 12 rotates in the direction opposite to the spin direction, and the internal gear 13 and the blades 14 are integrally formed.
It rotates in synchronization with the rotation of the spin table 3 and the substrate 2. In that case, the internal gear 13 and the blade 14
Is the rotation speed of the sun gear 11 (that is, the spin table 3
And the number of rotations of the substrate 2) and rotates in the opposite direction. Therefore, in this example, the planetary gear mechanism including the sun gear 11, the planetary gear 12, and the internal gear 13 constitutes the reduction mechanism of the present invention.

The rotation of the blade 14 generates an air flow in which the air in the region A above the blade 14 in the spin cup 6 flows downward and below the blade 14. At this time, the rotation of the spin table 3 and the substrate 2 generates wind in the spin cup 6 as in the related art, and air flows into the spin cup 6 from the upper opening of the spin cup 6 as shown by the arrow in the drawing. . The air flowing into the spin cup 6 is
The air flow generated by the rotation of the blade 14 effectively guides the spin table 3 to the outside of the outer periphery of the spin table 3 as indicated by an arrow in FIG. As a result, the amount of air flowing toward the substrate 2 on the spin table 3 is significantly reduced as compared with the related art.

As a result, the amount of air flowing into the spin cup 6 hitting the coating liquid R on the substrate 2 is reduced. Therefore, the coating liquid R that is forming a thin film on the substrate 2 is hardly affected by the air, and the formed thin film has a more uniform thickness.

In particular, since the blades 14 are arranged outside the outer periphery of the spin table 3, the air flowing into the spin cup 6 is more effectively guided outside the outer periphery of the spin table 3, and the spin The air flowing toward the substrate 2 on the table 3 is suppressed. Thereby, the influence of air on the coating liquid is further reduced.

At this time, the blades 14 rotate synchronously with the substrate 2 and the spin table 3, so that when forming a thin film, the number of rotations of the substrate 2 is set according to various sizes and various shapes of the substrate 2. , The blades 14 are rotated in accordance with the condition (2), so that the generated air flow also corresponds to the condition of the number of rotations of the substrate 2. Therefore, the forced air flow by the blades 14 can be easily controlled according to the rotation speed of the substrate on which the thin film is formed, that is, the type of the substrate, the thickness of the thin film, and the like. This also allows a thin film having a more uniform thickness to be formed. The air or mist forced to flow to the inlet of the exhaust duct 8 by the blades 14 is sucked by the fan 9 and flows into the exhaust duct 8 as in the related art, and is discharged through the exhaust duct 8.

By the way, the forced flow of the air downward from the spin table 3 by the blades 14 causes the air in the spin cup 6 on the upstream side A of the blades, that is, the spin table 3.
Also, the region in the spin cup 6 on the side where the substrate 2 is located does not become high in pressure. As a result, the excess mist of the coating liquid R flowing out from the substrate 2 does not flow upward due to the backflow as in the related art. Accordingly, the uniformity of the film thickness of the thin film formed since the mist hardly adheres to the substrate 2 is further improved, and the ejection to the outside from the upper opening of the spin cup 6 is more reliably suppressed. Become so.

Further, since the blades 14 are formed separately from the spin table 3, the rotation speed of the blades 14 can be controlled independently of the rotation speed of the spin table 3. Further, the blades 14 are decelerated by the planetary gear mechanism including the sun gear 11, the planetary gear 12, and the internal gear 13, and rotate at a speed lower than the rotation speed of the spin table 3. Accordingly, even if the blades 14 are provided outside the outer periphery of the spin table 3 and the moment of inertia increases, the rotation speed control of the blades 14 is simplified. In addition, since the planetary gear mechanism is disposed inside the ring-shaped blade 14, the spin coater 1 is formed compact. In particular,
Since the gears 11, 12, and 13 of the planetary gear mechanism are formed of resin, the spin coater 1 is formed to be lightweight and compact, and the generation of noise is prevented.

The rotation of the blades 14 generates an air flow from above to below. This air flow increases the pressure in the region B of the spin cup 6 below the blades 14 on the side of the exhaust duct 8. Although the case may be considered, as described above, the time required for the thin film forming process for one substrate 2 is an average,
Since it is relatively short in about 30 seconds, the pressure in the region B does not increase during the thin film forming process as in the related art.
Even if the pressure in the region B becomes high to some extent,
Since the air is forced to flow from above by the blades 14, the pressure in the region A above the blades 14 increases, and the excess mist of the coating liquid R adheres to the substrate 2 or the upper opening of the spin cup 6. Spouting from the part is greatly suppressed.

By the way, when the thin film forming process by the spin coater 1 is performed for a predetermined period, an excess mist of the coating liquid R adheres to and stays on the inner wall of the spin cup 6 and the blades 14. Therefore, as in the prior art, the cleaning substrate is set on the spin table 3 and the spin table 3 and the cleaning substrate are rotated while the cleaning liquid is allowed to flow from above to the upper surface of the cleaning substrate. As a result, the cleaning liquid flowing down to the upper surface of the cleaning substrate is scattered around by a centrifugal force, so that the scattered cleaning liquid cleans the inner wall and the blades 14 of the spic cup 6, and the mist adhering and staying on these is more effectively removed. Will be done. Other operations and other effects of the spin coater 1 of this example are the same as those of the above-described conventional example.

FIG. 2 is a diagram schematically showing another example of the embodiment of the present invention. The same components as those in the example shown in FIG. 1 described above are denoted by the same reference numerals, and detailed description thereof will be omitted. In the example shown in FIG. 1 described above, the spin table 3 and the blades 14 are formed separately, but in the spin coater 1 of this example, the blades 14 are attached to the outer periphery of the spin table 3 as shown in FIG. It is formed integrally with the spin table 3. Further, in this example, the speed reduction mechanism including the planetary gear mechanism in the example shown in FIG. 1 is not provided. Therefore, unlike the example shown in FIG. 1, the blades 14 rotate integrally with the spin table 3 in the same direction at the same rotation speed. Needless to say, even if the blades 14 rotate integrally with the spin table 3 in the same direction, the blades 14 flow downward from above the blades 14 as in the example shown in FIG.

Further, since the blades 14 are provided integrally on the outer periphery of the spin table 3, the number of parts is reduced, the structure becomes simple, and the assembling becomes easy accordingly. Other configurations, other operations and other effects of the spin coater 1 of this example are the same as those of the example shown in FIG.

On the other hand, the mist of the cleaning liquid at the time of cleaning also
The drain is efficiently drained as in the case of the mist of the excess coating liquid, and the same operation and effect as in the case of the mist of the excess coating liquid are obtained.

The sun gear 11, the planetary gear 12, the internal gear 13, and the blades 14 in the planetary gear mechanism of the above-described example may be made of other materials besides resin. In that case, it is desirable to use a relatively lightweight material such as a light metal material as the other material. In addition, another reduction mechanism may be provided in place of the reduction mechanism using the planetary gear mechanism.

The spin coater 1 of this embodiment is provided with the fan 9 and the flow control device 10 of the above-described conventional example. In the spin coater 1 of the present invention, the fan 9 and the flow control device 10 are used. It can be omitted.

[0041]

As is apparent from the above description, according to the spin coater of the present invention, the blades are rotated in synchronization with the rotation of the support table, and the rotation of the blades causes the blades to rotate outside the outer periphery of the support table. Since the air flow directed downward from the support table is generated, the air flow can effectively guide the air flowing into the container to the outside of the outer periphery of the support table. Therefore, the amount of air flowing toward the substrate on the support table can be significantly reduced as compared with the related art, and the amount of air flowing into the container and hitting the coating liquid on the substrate can be reduced. Accordingly, the coating liquid that is forming a thin film on the substrate can be prevented from being affected by the air, and the thickness of the formed thin film can be made more uniform.

In particular, by rotating the blades synchronously with the support table, when forming a thin film, the blades are rotated in accordance with the conditions of the number of rotations of the substrate set according to various sizes and shapes of the substrate. Therefore, the generated air flow can also correspond to the rotation speed condition of the substrate. Therefore, the forced air flow by the blades can be easily controlled according to the rotation speed of the substrate on which the thin film is formed, that is, the type of the substrate, the thickness of the thin film, and the like. This also makes it possible to form a thin film having a more uniform thickness.

Further, since the pressure of the support table and the region in the container where the substrate is located does not become high due to the forced flow of the air by the blades, the excess coating liquid flowing out of the substrate as in the conventional case is not used. Mist can be prevented from flowing backward and flowing upward. Therefore, the adhesion of the mist of the excess coating liquid to the substrate is suppressed, the uniformity of the film thickness of the thin film can be further improved, and the ejection to the outside from the upper opening of the container can be more reliably suppressed. Become like

In particular, according to the second aspect of the present invention, since the blades are arranged outside the outer periphery of the support table, the air that has flowed into the container from the upper opening of the container can be further increased outside the outer periphery of the support table. The air can be effectively guided, and the air flowing toward the substrate on the support table can be suppressed. Thereby, the influence of the air on the coating liquid can be further reduced.

According to the third aspect of the present invention, since the blades are provided integrally on the outer periphery of the support table, the structure can be simplified and the number of parts can be reduced accordingly. Further, according to the fourth aspect of the present invention, since the blades are formed separately from the support table, the rotation speed of the blades can be controlled independently of the rotation speed of the support table. Furthermore, according to the invention of claim 5, since the speed of rotation of the blades is reduced by the speed reduction mechanism from the speed of rotation of the support table, even if the blades are provided outside the outer periphery of the support table to increase the moment of inertia, The rotation speed of the blade can be easily controlled.

Furthermore, according to the invention of claim 6, since the speed reduction mechanism is constituted by a planetary gear mechanism, this speed reduction mechanism can be arranged inside the blade. Therefore, the spin coater can be formed compact. In particular, when the planetary gear mechanism is formed of resin, the spin coater can be formed to be lightweight and compact, and noise can be prevented from being generated.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing an example of an embodiment of a spin coater according to the present invention.

FIG. 2 is a diagram schematically showing another example of the embodiment of the present invention.

FIG. 3 is a diagram schematically illustrating an example of a conventional spin coater.

FIG. 4 is a diagram illustrating a problem of the conventional spin coater shown in FIG.

[Explanation of symbols]

1. Spin coater, 2. Substrate, 3. Spin table,
3a: rotating shaft, 4: spin motor, 5: bearing, 6: spin cup, 8: exhaust duct, 11: sun gear, 12: planetary gear, 13: internal gear, 14: blade

Claims (6)

[Claims] 1. A support table for supporting a substrate, which is accommodated in a container and to which a coating liquid is applied, on an upper surface, a driving means for rotating the support table, and air inside the container provided below the support table. And a discharge passage for discharging at least one of the mist to the outside of the container. The spin coater is provided in the container, and is rotated below the support table in synchronization with the support table. A spin coater comprising a blade for generating a directed air flow. 2. The spin coater according to claim 1, wherein the blade is disposed outside an outer periphery of the support table. 3. The blade according to claim 1, wherein the blade is provided integrally on an outer periphery of the support table.
The described spin coater. 4. The apparatus according to claim 1, wherein the blade is formed separately from the support table, and is provided below the support table and coaxially with the support table. Spin coater. 5. The spin coater according to claim 4, further comprising a speed reduction mechanism for rotating said blade at a speed lower than the rotation speed of said support table. 6. The spin coater according to claim 5, wherein said speed reduction mechanism is constituted by a planetary gear mechanism.