JPH0734887B2 - Thin film manufacturing equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improvement of a spin coating device (centrifugal coating device).

[Prior Art] Spin coating devices are used for recording disks of optical disks,
It is used as a device for applying photoresist (hereinafter referred to as resist) to a disk-shaped substrate such as a semiconductor wafer, or is used in various fields such as a coating device for hard coat film or antireflection film on the lens surface. .

Hereinafter, for simplification of the description, the conventional technique will be described by taking a recording disc of an optical disc as an example.

Conventionally, an apparatus as shown in FIG. 3 has been used to apply a resist (paint) to the disk-shaped substrate (hereinafter, simply referred to as a disk).

In FIG. 3, reference numeral 21 denotes a chamber, and a cover 24 for taking in and out a disk, which is an object to be coated, is provided on the upper portion. Twenty-two turntable units are mounted in the lower part of the chamber. Twenty-three discs are placed on the turntable and rotated. On the side surface of the chamber, there is a window 30 with a door 27 that can be opened and closed, and a resist supply nozzle 28 enters to drop the photoresist on the disk 23. A nozzle 25 for supplying clean air from the outside is provided at a position facing the central portion of the substrate. In the conventional example of FIG. 3, it is attached to 24 covers.
Reference numeral 26 is a regulator for adjusting the flow rate of clean air supplied to the nozzle 25. The gas in the chamber is exhausted to the outside through 29 exhaust ducts. The principle of application by the spinning method is that the resist is shaken off in the outer peripheral direction by the centrifugal force due to the rotation of the disk to form a thin film.

In that case, the thickness of the film formed on the disk is substantially determined by the viscosity and the rotation speed of the resist. Further, the concentration of the resist solvent that volatilizes from the resist and fills the inside of the chamber has a great influence on the formation of the resist film. Therefore, attempts have been made to keep the solvent concentration in the chamber constant by forcing a constant clean air from the outside to the center of the disk or by controlling the exhaust volume of the chamber so that it is always constant. ing. Further, in JP-A-54-73572 and JP-A-62-225269,
A spin coater having a plurality of gas supply ports has been proposed, and JP-A-59-52563 proposes to provide a sintering filter at the tip of the gas supply port.

[Problems to be Solved by the Invention] It is important that the resist film has a uniform film thickness within one disk at the same time as absolute thickness control.

Generally, when the rotation speed is high, the film pressure on the outer peripheral portion is thin, and when the rotation speed is low, the reverse is true, but this is not always the case. In the spinning method, it can be said that the film thickness is determined by the balance between the drying speed at which the resist is hardened and the shaking off speed due to the centrifugal force of rotation. Therefore, there is a limit in controlling the uniformity of the film only by the factors of the resist viscosity and the rotation speed.

In addition, if the film to be formed is very thin, such as on the order of angstroms, such as the above-mentioned master of an optical disc or a semiconductor wafer, the resist dries immediately after the start of rotation. It has been very difficult to realize a desired film thickness with high accuracy and without variation in inner and outer circumferences. Therefore, the conventional technique has a serious problem that the thickness of the formed thin film varies. Further, the proposals of JP-A-54-73572, JP-A-62-225269, and JP-A-59-52563 do not control the supply amount of a plurality of gas supply ports, so that each position is not controlled. It was difficult to control the drying rate of the resist.

An object of the present invention is to provide a thin film manufacturing apparatus capable of stably forming a uniform resist film in a spinning method in order to solve the above-mentioned problems of the prior art.

[Means for Solving the Problems] In order to achieve the above object, the thin film manufacturing apparatus of the present invention comprises a chamber (1) for applying a coating material to a disk-shaped substrate,
A turntable unit (2) for rotating the disk-shaped substrate in the chamber, a paint supply nozzle (8) for dropping paint on the surface of the disk-shaped substrate in the chamber, and a A thin-film manufacturing apparatus including exhaust ducts (10, 11) for exhausting gas, wherein a plurality of gas supply nozzles (5a, 5b, 5c), and the plurality of gas supply nozzles are provided with flow rate control means (6a, 6b, 6c) for supplying different flow rates of gas, respectively.
It is characterized by having.

In the above structure, it is preferable that a filter (15) made of a porous material is attached to the tip of the gas supply nozzle.

In the above configuration, it is preferable that the gas flow rate control means is a pressure regulator.

[Operation] According to the above-described configuration of the present invention, when the coating material is applied to form a thin film, gas is supplied from a plurality of gas supply nozzles provided at different radial positions on the surface of the disk substrate. Since it can be sprayed, a thin film having a predetermined uniform film thickness can be efficiently formed over the entire surface of the disk-shaped substrate.

Further, according to the present invention, since the plurality of gas supply nozzles are provided with the flow rate control means for supplying different flow rates of gas, gas supply nozzles corresponding to different radial positions on the disk surface are provided. Since different amounts of gas can be blown out from the nozzles, the concentration of the paint (resist) solvent in the atmosphere at each radial position can be adjusted, and the resist drying rate at each position can be freely controlled. It is possible to make the film thickness formed on the entire surface constant.

Further, according to the preferable configuration of the present invention, since a filter made of a porous material is attached to the tip of the gas supply nozzle, it is possible to obtain a uniform flow velocity without unevenness in the flow velocity of the gas to be supplied. A thin film having a uniform film thickness can be efficiently formed. In the above,
According to a preferable example in which the gas flow rate control means is a pressure regulator, the gas flow rate can be controlled more accurately, which is practical.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In FIG. 1, reference numeral 1 is a chamber, and a turntable unit 2 is attached to the lower portion thereof. 3 is a disk placed on the turntable. At the top of the chamber there is a cover 4 for loading and unloading the disc. A window 12 is provided on a part of the side surface of the chamber, and a door 7 that can be opened and closed is provided. Reference numeral 8 denotes a paint supply nozzle (resist supply nozzle) that can freely enter and leave the window 12.

It is preferable to provide a far part 9 that surrounds the disk 3 on the inner side surface of the chamber. The far part 9 is provided at a position slightly higher than the disc 3. Further, it is preferable to provide an exhaust duct 10 on the side surface of the chamber above the far part 9. A plurality of exhaust ducts 10 may be provided.

In addition, there is a groove 13 in the lower part of the chamber for collecting the resist scattered from the disk, and a drain 14 is formed in a part of the groove 13.
Is provided. Further, the exhaust duct 11 is provided on the side surface of the groove 13. Gas in the chamber is discharged from the exhaust ducts 10 and 11 by an exhaust fan (not shown).

The cover 4 is provided with a plurality of gas supply nozzles 5a, 5b, 5c for supplying clean air into the chamber. In addition to clean air, any gas such as nitrogen gas can be supplied. Further, the clean air as used herein is preferably air that has been cleaned of dust and particles in the air and that has been dried.

The plurality of gas supply nozzles 5a, 5b, 5c have dedicated flow rate control means 6a, 6b, 6c, respectively. These are, for example, pressure regulators. The gas supply nozzles 5a, 5b, 5c are provided so as to face different radial positions of the disk. The number of gas supply nozzles may be any number as long as it is plural, and the gas supply nozzles are arranged linearly or non-linearly with respect to the radial position of the disk.

FIG. 2 shows the gas supply nozzle 5 attached to the cover 4.
In another embodiment of the present invention, a filter 15 made of a porous material is attached to the tip of the nozzle.

The operation of the configuration of the embodiment of the present invention will be described below.

The resist is dropped from the paint supply nozzle 8 onto the rotating disk 3. After that, the resist spreads thinly by the shake-off action by the rotation of the disk to form a film. Most of the resist shaken off from the disc hits the side surface of the chamber and bounces off, but since it has the fart portion 9, it can be prevented from returning to the top of the disc 3. After that, the resist is stored in the groove 13 and collected from the drain 14. The airflow generated by the rotation of the disk passes over the far part 9 and is discharged from the exhaust duct 10. Exhaust from the far part 9 to the lower measuring part is performed by an exhaust duct 11.

In addition, a window for entering and leaving the paint supply nozzle 8
Since 12 is provided on the fart portion 9, it is possible to prevent the resist 12 from coming off from the window 12 which has been shaken off.

When the disk is rotating while shaking off the resist, clean air is supplied from the gas supply nozzles 5a, 5b and 5c to accelerate the evaporation of the solvent of the resist on the disk and accelerate the drying. The resist film thickness formed on the disk is determined by the balance between the speed of hardening by drying and the speed of spreading by centrifugal force.

According to the above configuration, there are a plurality of gas supply nozzles at different radial positions on the disk, and the amount of clean air supplied from each nozzle can be adjusted by a dedicated pressure regulator. In other words, by adjusting these, you can control the resist drying speed at each radial position,
The film thickness can be made uniform over the inner and outer circumferences. Also,
Since the gas supplied from the gas supply nozzle and the gas containing the solvent gas generated in the chamber are discharged from the exhaust duct 10, the air flow on the disk does not stay smoothly.

Therefore, the formed film is smooth and stable, and does not vary between batches or due to changes over time.

In the embodiment shown in FIG. 1, the exhaust ducts are provided in the upper part and the lower part of the fart, respectively, but they may be provided only in the lower part to exhaust air unitarily.

Since the gas supply nozzle shown in FIG. 2 is provided with a porous filter at its tip, the flow rate of the clean air supplied can be reduced and a soft and uniform air can be applied to the disk surface.

Although the number of nozzles is three in FIG. 1, more nozzles may be provided according to the size of the disk. The gas supply nozzle may be attached at a position facing the disk surface, and is not limited to the cover shown in FIG.

Although one embodiment of the present invention has been described with respect to the recording disk of the optical disc, the present invention is not limited to this.
INDUSTRIAL APPLICABILITY The spin coating apparatus of the present invention can be used in various fields such as an apparatus for producing a peritoneum such as a semiconductor wafer or a coating apparatus for a hard coat film or an antireflection film on a lens surface.

According to the embodiment of the present invention described above, it is possible to form a uniform resist film on the disk without unevenness in the inner and outer circumferences. Further, since the air flow on the disk is smooth and there is no irregular flow, the desired thin film can be obtained very stably.

[Effects of the Invention] As described above, according to the present invention, when a coating is applied to form a thin film, a plurality of gas supply nozzles are provided facing each other at different radial positions on the surface of a disk-shaped substrate. Since the gas can be blown, it is possible to achieve an excellent effect that a thin film having a predetermined uniform film thickness can be efficiently formed over the entire surface of the disk-shaped substrate.

Further, according to the present invention, since the plurality of gas supply nozzles are provided with flow rate control means for supplying different flow rates of gas, the gas supply nozzles respectively corresponding to different radial positions on the disk surface. Since different amounts of gas can be blown out from each of them, and the resist (solvent) solvent concentration in the atmosphere at each radial position can be adjusted, the resist drying rate at each position can be freely controlled. It is possible to achieve the further excellent effect that the formed film thickness can be made uniform over the entire surface.

Further, according to the preferable configuration of the present invention, since a filter made of a porous material is attached to the tip of the gas supply nozzle, it is possible to obtain a uniform flow rate without uneven flow rate of the gas to be supplied. It is possible to achieve the further excellent effect that a thin film having a uniform film thickness can be efficiently formed. Further, in the above, according to a preferable example in which the gas flow rate control means is a pressure regulator, the gas flow rate can be controlled more accurately, which is practical.

[Brief description of drawings]

FIG. 1 is a sectional view of a thin film manufacturing apparatus which is an embodiment of the present invention, FIG. 2 is a sectional view showing another embodiment of a gas supply nozzle of the present invention, and FIG. 3 is a conventional resist coating apparatus. A sectional view is shown. 1 ... Chamber, 2 ... Turntable unit, 3 ... Disk recording substrate, 8 ... Paint supply nozzle, 5a, 5b, 5c ... Gas supply nozzle, 10, 11 ... Exhaust duct.

Claims (3)

[Claims] 1. A chamber (1) for applying a coating material to a disc-shaped substrate, a turntable unit (2) for rotating the disc-shaped substrate in the chamber, and the disc-shaped substrate in the chamber. A thin film manufacturing apparatus including a paint supply nozzle (8) for dripping paint on the surface of the substrate and an exhaust duct (10, 11) for exhausting gas in the chamber, wherein the disc-shaped substrate surface is different. Gas supply nozzles (5a, 5a)
b, 5c), and the plurality of gas supply nozzles are provided with flow rate control means (6a, 6b, 6c) for supplying different flow rates of gas, respectively. . 2. The thin film manufacturing apparatus according to claim 1, wherein a filter (15) made of a porous material is attached to the tip of the gas supply nozzle. 3. The thin film manufacturing apparatus according to claim 1, wherein the gas flow rate control means is a pressure regulator.