JPH02229579A - Spin coating device - Google Patents

Abstract

PURPOSE:To prevent the generation of a defect arising from the solidification of a coating agent by providing a heat insulating means between a turn table and a spindle shaft and further, providing a means for adjusting the temp. and humidity of the atmosphere around the turn table. CONSTITUTION:The heat insulating means which interrupts the heat transfer between the turn table 12 and the spindle shaft 13a and the temp. and humidity adjusting means for adjusting the temp. and humidity of the atmosphere around the table 12 are provided. The environment most adequate for the solidification of the coating agent applied on an object 11 to be coated is obtd. by this constitution. The generation of the defect, such as ruggedness, on the surface at the time when the coating agent solidifies is obviated.

Description

TECHNICAL FIELD The present invention relates to a spin coating apparatus for forming a recording film by applying a coating fluid onto information recording tracks formed on a disc substrate of an optical disc, for example, and solidifying the coating fluid.

Background technology FIG. 2 shows a conventional spin coating apparatus.

As shown in the figure, the spin coating apparatus has a rotary table 3 which carries a disk substrate 1 as a work target and is rotationally driven by a spindle motor 2.

A spinner bowl 4 is provided to surround a working area around the rotary table 3, and a guide pipe 5 is provided above the spinner bowl. The guide tube 5 allows a liquid coating agent supplied from a supply source (not shown) to flow down onto the disk substrate 1 through a nozzle 6 . The coating agent applied to the disk substrate 1 naturally solidifies, thereby forming a recording film on the disk substrate 1.

The disk substrate 1 is coated using the spin coating device described above.
The recording film formed on the surface is affected by the atmospheric environment when the coating material solidifies. As a result, small defects such as unevenness may occur on the surface.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a spin coating apparatus that prevents the occurrence of defects due to solidification of a coating agent.

The spin coating apparatus according to the present invention has a heat insulating means for cutting off heat transfer between a rotary table that supports a workpiece and a spindle shaft that transmits rotational force to the rotary table, and further includes an atmosphere surrounding the rotary table. The present invention is characterized in that it has temperature and humidity adjustment means for adjusting the temperature and humidity of the workpiece, thereby providing an optimal environment for coagulating the coating agent applied to the workpiece.

EXAMPLE Hereinafter, a spin coating apparatus as an example of the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, the spin coating apparatus has the following features:
It has a disc-shaped rotary table 12 that concentrically supports a disc substrate 11 to be worked on. Note that the disk substrate 11 is obtained by injection molding a transparent resin as a material. Further, after forming a recording film on the disk substrate 11 using the spin coating device,
Furthermore, it is sent to a post-process and subjected to various processing, thereby obtaining an optical disc as a finished product.

The rotary table 12 is formed by combining three members, for example, a boss 12a1, an intermediate plate 12b, and a disk substrate abutting plate 12c, and is fitted onto a spindle shaft 13a of a spindle motor 13 at a boss 12g, and is given rotational driving force. These bosses 12a1 intermediate plate 12b
At least one of the disk substrate contact plates 12c is made of a heat insulating material, thereby cutting off heat transfer between the disk substrate supporting surface 12d of the rotary table 12 and the spindle shaft 13a.

A guide tube 15 whose tip end is bent at a substantially right angle is provided above the rotary table 12 in parallel with the disk substrate supporting surface 12d of the rotary table. This guide tube 15 guides liquid coating agent supplied from a supply source (not shown) onto the disk substrate 11 placed wc on the rotary table 12, and has an opening above the rotary table 12. The coating agent is caused to flow down from the tip through the nozzle 16. A cock 1 is installed in the middle of the guide tube 15.
7 is provided, and the flow of the coating agent from the guide tube 15 and its stoppage are achieved by automatically opening and closing this cock 17 at predetermined timing. In addition, the coating agent is discharged from the nozzle 16 using a rotary table 12.
The nozzle 16, together with the guide tube 15, rotates the rotary table 12 as the coating agent is discharged.
is moved in the radial direction.

A spinner box 19 is provided which surrounds the rotary table 12 together with the disk substrate 11 carrying it. The spinner box 19 is preferably made of a heat insulating material and has an opening 19a formed in its upper surface, and an air cleaner 20 is provided in the opening 19. An outer box 21 made of a heat insulating material is provided which surrounds the spinner box 19 with a gap in between.
A centrifugal fan 22 is provided inside the spinner box 19 and outside the spinner box 19. One end of the air supply pipe 23 is connected to the air intake port of the centrifugal fan 22, and the other end of the air supply pipe 23 is led out of the outer box 21 via the airtight member 24 and is connected to the air discharge port of the air cooler 25. is connected to. An air heater 26 is disposed on the side of the air cooler 25, and the air inlet of the air cooler 25 and the air heater 26
The connecting pipe 27 communicates with the air outlet. A dehumidifier 29 that dehumidifies the air is provided at a position sandwiching the air heater 26 together with the air cooler 25, and the air outlet of the dehumidifier and the air intake of the air heater 26 are connected by a connecting pipe 30. It is communicated.

A funnel-shaped air collection member 31 is disposed on the side of the dehumidifier 29 , and the reduced diameter portion of the air collection member 31 and the air intake port of the dehumidifier 29 are connected by a relay pipe 32 . Air collection member 31
An air cleaner 33 is fitted into the enlarged diameter portion.

On the other hand, an exhaust pipe 36 is provided so as to penetrate the side wall of the outer box 21 via an airtight member 35, and the internal space of the spinner box 19 and the atmosphere side outside the outer box 21 are communicated through the exhaust pipe 36. ing. Further, an airtight member 37 is also interposed between the exhaust pipe 36 and the side wall of the spinner box 19. Note that the coating agent guide pipe 15 located above the exhaust pipe 36 also has side walls of the spinner box 19 and the outer box 21 sealed with an airtight member 38.
and 39, but as described above, since the guide tube 15 is moved along the disk substrate supporting surface 12d of the rotary table 12 by a driving means (not shown), it can smoothly connect with these airtight members 38 and 39. There is a sliding contact.

A cock 41 for opening and closing the exhaust pipe is provided at the tip of the exhaust pipe 36 described above. One end of a circulation pipe 42 is connected to the center of the exhaust pipe 36, and a funnel-shaped air diffusion member 43 is attached to the other end of the circulation pipe at its reduced diameter portion. The enlarged diameter portion of the air diffusion member 43 is communicated with the enlarged diameter portion of the air collection member 31 via an airtight packing 44. Further, a cock 45 for opening and closing the circulation pipe is provided near one end of the circulation pipe 42, and an intake pipe 46 for introducing outside air into the circulation pipe is connected near the other end. There is. Further, the intake pipe 46 is provided with a cock 47 for opening and closing the intake pipe.

A temperature sensor 48 and a humidity sensor 49 are provided so that their detection parts protrude into the interior space of the spinner box 19 surrounding the rotary table 12.

The measured values of the temperature sensor 48 and humidity sensor 49 are sent to the microcomputer 50 via cables 48a and 49a, and the microcomputer 50 controls the centrifugal fan 22, air cooler 25, air heater 26, and dehumidifier based on these measured values. 29 as appropriate. In addition, each cable 4
An opening formed in the side wall of the outer box 21 to lead out the outer box 21 is closed with a grommet 51 made of rubber or the like.

In the spin coating apparatus configured as described above, the coating agent is applied by flowing down onto the disk substrate 11 from the nozzle 16 in synchronization with the rotation of the rotary table 12. Further, the temperature and humidity of the atmosphere around the rotary table 12 are measured by a temperature sensor 48 and a humidity sensor 49, respectively, and the microcomputer 50 controls the centrifugal fan 22, air cooler 25, and air heater 26 according to these measured values. and the dehumidifier 29 are activated or stopped as appropriate. As a result, the temperature and humidity of the atmosphere are maintained within the optimal range for coagulating the cauling agent applied to the disk substrate 11. Incidentally, the most suitable temperature for coagulating the coating agent varies depending on the type of coating agent, but is, for example, 23° C. and the humidity is 40% or less. Further, as described above, the rotary table 12 supporting the disk substrate 11
Since a heat insulating means is provided to cut off heat transfer between the spindle motor 13a and the spindle motor 13a,
The heat generated by the disk passes through the rotary table 12 to the disk substrate 11.
It never reaches.

Because of this configuration, it is possible to obtain an optimal environment for solidifying the coating agent applied to the disk substrate 11, and no defects occur when the coating agent solidifies.

The above-mentioned coating operation is performed as follows depending on the temperature and humidity of the outside air outside the outer box 21.

When the temperature and humidity of the outside air outside the outer box 21 are within or near the optimum range for coagulating the coating agent, the cock 45 is closed and the cocks 41 and 47 are opened. That is, outside air is taken in through the intake pipe 46, dehumidified, heated or cooled, and then supplied under pressure by the centrifugal fan 22, and then discharged to the outside of the outer box 21 through the exhaust pipe 36.

On the other hand, if the temperature and humidity of the outside air are within a range that would adversely affect the solidification of the coating agent, the cocks 41 and 47 are closed, and only the cock 45 is opened. That is,
The air that has been dehumidified by the dehumidifier 29 and brought to an appropriate temperature by the air heater 26 and air cooler 25 is not discharged, but is circulated through the circulation pipe 42. Because of this configuration,
The energy required to heat or cool the air is reduced,
A reduction in operating costs has been achieved.

Effects of the Invention As detailed above, the spin coating apparatus according to the present invention includes a heat insulating means for cutting off heat transfer between the rotary table that supports the workpiece and the spindle shaft that transmits rotational force to the rotary table, and the rotary table. and temperature/humidity adjustment means for adjusting the temperature and humidity of the surrounding atmosphere.

Because of this configuration, it is possible to obtain the most suitable environment for solidifying the coating agent applied to the workpiece, and no defects occur when the coating agent solidifies.

[Brief explanation of the drawing]

FIG. 1 is a partially cross-sectional front view of a spin coating apparatus according to an embodiment of the present invention, and FIG. 2 is a partially cross-sectional front view of a conventional spin coating apparatus. Explanation of symbols of main parts 11...Disk board 12...Rotary table 13a...Spindle shaft 9...
... Spinner box 0, 33 ... Air cleaner 1 ... Outer box 22 ... Centrifugal fan 5 ... Air cooler 26 ...・Air heating machine 9・・・Dehumidifier

Claims (1)

[Claims] A spin coating apparatus includes a spindle motor, a rotary table attached to a spindle shaft of the spindle motor to support a workpiece, and a fluid supply means for causing a coating fluid to flow down toward the workpiece on the rotary table. A spin coating apparatus comprising: a heat insulating means for cutting off heat transfer between the rotary table and the spindle shaft; and a temperature and humidity adjusting means for adjusting the temperature and humidity of the atmosphere around the rotary table. .