JPH0487664A - Rotary treating device for square substrate - Google Patents

Abstract

PURPOSE:To prevent the sticking of concentrated mists to the rear surface of the angle parts of a substrate during rotation by erecting partition walls to block the inflow of treating liquid mists into the lower spacing of the substrate on a turntable near the angle parts of the substrate existing on the downstream side of rotation on the respective sides of the square substrate. CONSTITUTION:The turntable 2 which has the size exceeding the outside dimension of the square substrate 1 and rotates the substrate 1 in the state of horizontally positioning and supporting the substrate at a small spacing and an upper rotating plate 3 which is disposed parallel apart a prescribed small spacing from the front surface of the substrate 1 supported on the turntable 2, has the size exceeding the outside dimension of the substrate 1 and is rotated integrally with the turntable 2 are provided. The outer peripheral edge of the flat treating space formed between the turntable 2 and the upper rotating plat 3 is opened to allow the splashing and flowing out of the excess treating liquid. The partition walls 24 which block the inflow of the treating liquid mists to the lower spacing of the substrate are erected on the turntable 2 near the angle parts of the substrate existing on the downstream side of rotation.

Description

[Detailed Description of the Invention] <Industrial Field of Application> The present invention is applicable to a rotary processing apparatus used for applying a resist solution to a surface of a rectangular substrate such as a glass substrate for a liquid crystal display, a phenomenon processing, an etching process, etc. In particular, the present invention relates to a technique for preventing processing liquid mist from flowing around to the back side of a substrate.

<Prior art> Rotary processing equipment basically supports a substrate to be processed horizontally mounted on a rotating table that rotates around a vertical axis, and drops a processing liquid onto the center of the surface of the loaded substrate. By rotating, the processing liquid is spread radially outward of the substrate by centrifugal force, and the processing liquid is uniformly applied or flowed over the substrate surface.

However, when rotating a square substrate as described above,
The air layer near the corner of the substrate is disturbed by the wind blowing phenomenon at the corner of the substrate, which sometimes causes variations in the flow state of the processing liquid (particularly, in the case of a rotary coating device, the film thickness) in this region.

Therefore, as a means to eliminate such problems, the present applicant has proposed a device that solves the above problems in a patent application dated June 26, 1990 (title of invention "Rotary Coating Apparatus"). are doing.

Hereinafter, the previously proposed rotary coating device will be explained with reference to FIG.

This rotary coating device includes a rotary table 2, which has a size exceeding the outer diameter of the substrate 1, and rotates in a fixed direction while horizontally positioning and supporting the substrate 1 at small intervals, and the rotary table 2.
The upper part is arranged parallel to the upper surface of the substrate at a predetermined small interval, has a size exceeding the outer diameter of the substrate 1, and is rotated integrally with the rotary table 2. The outer periphery of the flat coating processing space S formed between the rotary plate 3 and the rotating plate 3 is closed to allow surplus coating liquid to scatter and flow out, and the air layer in the coating processing space S is rotated together with the substrate 1 It has the feature that by rotating it, it is possible to suppress the wind blowing phenomenon caused by the corners of the substrate.

<Problems to be Solved by the Invention> The proposed device described above prevents the wind-cutting phenomenon at the corners of the substrate and enables uniform coating on the surface of the substrate.
The following new technical issues were identified.

When a square substrate is loaded into this rotary coating device r, the sixth
As shown in the figure, the coating liquid R supplied to the center of the surface of the substrate 1 diffuses and flows in a substantially circular shape as the substrate rotates, and the excess coating liquid flows from the approximate center of each side of the substrate L. begins to scatter outward.

Therefore, the coating liquid mist scattered from the center of each edge of the substrate I is absorbed into the corner of the substrate on the lower side of rotation (for example, as shown in FIG. 6, the base film rotates counterclockwise). In this case, the board corner IA at the board edge 1a,
Corner IB on end side 1b, corner 1c on end side 1c
, #A corner ID at side 1d) entered the substrate 1, and it was found that the coating liquid mist was deposited on the back surface of the four corners of the substrate 1 in the range indicated by the hatched portion Q in FIG.

In addition, when the substrate 1 is rectangular, as shown in Figure 8, most of the excess coating liquid R of the supplied coating liquid R scatters outward from the center of the long side. Coating liquid mist adhered to the back surface of the substrate 1 in the area indicated by the hatched area Q in the ninth test.

Therefore, as shown in FIG. 1O and FIG. We tried a method to prevent the coating liquid mist from going around to the outside of the back surface of the substrate. Here, the reason why the minute interval 25 is provided between the partition wall 24 and the substrate 1 is to prevent dirt from adhering to the back surface of the substrate 1 due to the upper end of the partition wall 24 coming into contact with the substrate l. .

According to this means, it is possible to effectively prevent the coating liquid mist from going around to the back side of the substrate during the rotation process.
Although the concentrated coating liquid adhesion near the corners of the substrate shown in Figures and Figure 9 disappeared, a new phenomenon occurred in which the coating liquid mist was dispersed and adhered in fine particles to the entire back surface of the substrate. did.

This phenomenon is considered to be due to the following causes.

In other words, during the rotation process, the air on the back side of the substrate 1 flows outward due to centrifugal force, creating a negative pressure, and as soon as the rotation is stopped, the air containing the fine coating liquid mist on the outer periphery of the substrate flows out. It is thought that the particles quickly flow into the space below the substrate through the small gap 25 between the partition wall 24 and the back surface of the substrate and diffuse widely, so that they are dispersed and adhere to the back surface of the substrate.

The present invention has been made in view of the above circumstances, and it is possible to prevent the mist from adhering to the back surface of the corner of the substrate during rotation, and to prevent the mist from adhering to the back surface of the substrate immediately after the rotation has stopped. It is an object of the present invention to also reduce adhesion caused by wraparound.

<Means for Solving the Problem> In order to achieve such an object, the invention according to claim (1) has a size exceeding the outer diameter of a rectangular substrate, and the substrate is horizontally positioned at small intervals. a rotary table that rotates in a fixed direction while being supported; the rotary table is arranged parallel to the upper surface of the substrate supported on the rotary table at a predetermined small interval, and has a size exceeding the outer shape of the substrate; It is equipped with an upper rotary plate that rotates integrally with the rotary table, and the outer peripheral edge of a flat processing space formed between the rotary table and the upper rotary plate is opened to enable the splashing and outflow of excess processing liquid. In the rotational processing apparatus for a square substrate, a partition wall for preventing processing liquid mist from flowing into a gap below the substrate is installed above the rotating table in parallel with the side near the corner of the substrate on the lower side of rotation on each side of the square substrate. It was erected.

The invention described in claim (2) is particularly directed to rectangular substrates, and similarly to the invention described in claim (]) B, the invention described in claim (2) has a size that exceeds the outer shape of the substrate, and the substrates are spaced apart at small intervals. A rotary table that rotates in a fixed direction while being positioned and supported horizontally;
An upper rotating plate is arranged parallel to the upper surface of the substrate supported on the rotating table at a predetermined small interval, has a size exceeding the outer diameter of the substrate, and is rotated integrally with the rotating table. A rotational processing apparatus for a square substrate, comprising: an outer peripheral edge of a flat processing space formed between the rotating table and an upper rotating plate, the outer periphery of which is opened to enable the scattering and outflow of surplus processing liquid;
A characteristic feature of the invention described in claim (2) compared to the invention described in claim (]) is that the processing liquid is placed near the corner of the substrate on the long side of the rectangular substrate on the lower side of rotation. A pair of partition walls that prevent mist from flowing into the gap below the substrate are erected on the rotary table.

<Function> According to the above configuration, during rotation processing, the partition wall installed on the rotating table prevents the processing liquid mist from flowing concentratedly into the vicinity of the corners of the substrate, so that the back surface near the corners of the substrate cannot be processed. Concentrated adhesion of liquid mist is prevented.

In addition, the partition walls are not placed facing the entire periphery of the board, but are provided partially, so in areas where the partition walls are not present, there is a relatively wide space between the back surface of the board and the substrate rotating table. Therefore, the space below the board becomes negative pressure due to the outflow of air during rotation, and even if air flows into this space from the outside when the rotation stops, this air will flow through the partition wall. It will flow in slowly and gently from wide spaces with no gaps. Therefore, the processing liquid mist contained in the incoming air often falls onto the rotary table due to its own weight before it reaches the depths of the space below the substrate, and it is extremely unlikely to adhere to the back surface of the substrate.

<Example> Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIGS. 1 to 3 show an embodiment of a rotary coating device, which is an example of a rotary processing device according to the present invention.

This rotary coating device includes a rotary table 2 on which a square substrate 1 is mounted and rotates horizontally around a vertical axis 2, and an upper part installed above the rotary table 2 parallel to the rotary table 2 and rotating together with the rotary table 2. A rotary plate 3, an upper support plate 4 that supports the upper rotary plate 3, a waste liquid recovery case 5 fixed and weight-resistant so as to surround the lower part and the periphery of these rotary members, and an output as a vertical rotating shaft. The motor 7 has a shaft 6 erected thereon.

This motor 7 is connected and supported by a bracket 9 provided on a base plate 8, and a central boss 10 of the rotating table 2 is fitted onto the vertical rotating shaft 6 from above, and a drive bin 6a provided on the rotating shaft 6 is connected to the motor 7. The rotation is transmitted by engaging the notch 10a of the boss 10.

The rotary table 2 is configured as a disk having an outer diameter sufficiently larger than the external shape of the substrate 1, and the substrate 1 is horizontally mounted and supported on a group of many substrate support pins 11 erected on its upper surface. It has become. Further, on the rotary table 2, there are provided a pair of 4 ml engaging bottles 12 that engage with the four corners of the base Fi1, and these pins 12 horizontally rotate the substrate 1 together with the rotary table 2.

Furthermore, as shown in FIG. 2, the retaining pin 12 has a substrate l.
A resin collar 13 is fitted onto the outside so as not to damage the edge of the tube.

Further, on the outer peripheral upper surface of the rotary table 2, a spacer ring 14 and a ring plate 15 having the same outer diameter as the rotary table 2 are connected at a plurality of locations in the same radial direction. is detachably attached via a knob bolt 16, and by removing the upper support plate 4, the substrate l can be taken in and out from the central opening of the ring plate 15. Note that a handle 17 for attachment and detachment is provided on the upper center surface of the upper support plate 4.

The spacer ring 14 has an inner circumferential surface formed into a conical surface with an upward slope, and a gap 20 for waste liquid outflow corresponding to the thickness of the upper and lower washers 19 fitted onto the connecting bolt 18 is set between the upper and lower sides. is formed.

The upper rotary plate 3 is formed into a circular plate having a larger diameter than the outer shape of the substrate 1, and is connected to the lower surface of the upper support Fi4 via a collar 21 with bolts.

The bottom of the waste liquid recovery case 5 is narrowed, and a waste liquid discharge port 22 is formed at the lower end thereof, and exhaust ports 23 are formed at multiple locations in the circumferential direction for discharging the solvent gas and coating liquid mist evaporated from the coating liquid. has been done.

The above configuration is similar to the rotary coating apparatus previously proposed by the present applicant, and in this embodiment, the following configuration is added to this.

That is, on the top surface of the rotary table 2, a partition wall 24 is erected parallel (not necessarily parallel) to the vicinity of the corner of the board on the lower side of rotation on each side of the board l, and the partition wall 24 is 0.5 so that the top edge does not touch the board 1
They are opposed to the substrate surface with a small interval 25 of about 1.0 mm.

The rotary coating apparatus of this embodiment is constructed as described above, and in the coating process, first, the upper support plate 4 is removed and the substrate 1 is placed on the group of substrate support pins 11 of the rotary table 2 in a predetermined posture. Install and set.

Next, a coating liquid supply nozzle (not shown) is moved above the center of the substrate 1, and a predetermined amount of the coating liquid is dripped and supplied.

After that, the upper support plate 4 is mounted and fixed on the ring plate 15, and the motor 7 is started to move the rotary table 2 and the upper support plate 4.
, the upper rotating plate 3 and the substrate 1 are horizontally rotated together.

As a result of this rotation, the coating liquid on the substrate 1 is diffused and flowed outward by centrifugal force, and is applied thinly to the upper surface of the substrate 1.

In this case, the air layer in the flat coating processing space S formed between the rotary table 2 and the upper rotary plate 3 also rotates together, and the substrate l
Diffusion flow of the coating liquid is performed in a state where no airflow is generated above.

The excess coating liquid that flows on the substrate 1 and reaches the outer periphery is transferred to the substrate 1.
It flows out from the periphery and scatters from the entire outer periphery of the coating processing space S. Then, the scattered excess coating liquid passes through the gap 20 formed above and below the spacer ring 14, flows into the waste liquid recovery case 5, and is recovered.

In this case, the scattering of the excess coating liquid from the periphery of the substrate 1 is caused by the sixth
As shown in the figure, starting from the center of each side, the side 1e near the corner of the substrate on the lower side of rotation (see Figure 3) plunges into the coating liquid mist, but below the side 1e near the corner of the substrate. A partition wall 24 erected on the rotary table 2 along the side prevents the coating liquid mist from flowing into the space below the substrate.

Furthermore, when the coating process is completed and the rotation is stopped, external air slowly flows into the negative pressure space below the substrate from the opening where the partition wall 24 does not exist, so that the coating liquid on the back surface of the substrate is The degree of mist adhesion is reduced.

FIG. 4 shows an embodiment in which the substrate 1 is rectangular. In this case, the long side of the rectangular substrate 1 is parallel (not necessarily parallel) to the side near the corner of the substrate on the lower side of rotation.
By simply erecting a pair of partition walls 24 with a length of 1/3 to 1/2 of the long side length, it is possible to sufficiently prevent the coating liquid mist from flowing into the space below the substrate during rotation.

Note that the present invention is applicable not only to coating processing on square substrates, but also to developing processing, etching processing, etc.

<Effects of the Invention> As explained above, according to the present invention, processing liquid mist entering the space below the substrate and being concentrated on the back surface near the corners of the substrate during rotation processing can be prevented from being deposited on the rotating table. This can be effectively prevented with an upright partition wall. In addition, since the partition wall is partially provided, when the rotation is stopped, the negative pressure slows down the flow of external air into the space below the substrate, which suppresses the suction and diffusion of the processing liquid mist. It is possible to reduce the dispersion of the processing liquid mist from adhering to the entire back surface.

[Brief explanation of the drawing]

1 to 3 show a rotary coating device which is an embodiment of the present invention, FIG. 1 is a vertical sectional view of the entire rotary coating device, FIG. FIG. 3 is a partially cutaway plan view of the main part. Further, FIG. 4 is a plan view of a main part of an embodiment for processing a rectangular substrate. In addition, Fig. 5 is a vertical cross-sectional view of the main parts of the previously proposed rotary coating device, Fig. 6 is a plan view showing the diffusion and flow state of the processing liquid on a square rectangular substrate, and Fig. 7 is the back side of the square substrate. FIG. 8 is a back view showing the degree of contamination of the processing liquid wave rP1. on a rectangular square substrate. A plan view showing the pumping state, FIG. 9 is a rectangular board i
FIG. 10 is a partially cutaway plan view showing possible means for eliminating the stain, and FIG. 11 is a sectional view taken along the line A--A in FIG. 10. 1... Substrate 2... Turntable 3... Upper turntable 24... Partition wall S... Coating processing space Applicant Dainippon Screen Mfg. Co., Ltd. Agent Patent attorney Tsutomu Sugitani Figure 10 Figure Figure

Claims (2)

[Claims] (1) A rotary table whose size exceeds the outer diameter of a rectangular substrate and rotates the substrate in a fixed direction while positioning and supporting the substrate horizontally at small intervals; an upper rotary plate that is arranged in parallel with a small interval, has a size that exceeds the outer diameter of the substrate, and is rotated integrally with the rotary table, and is formed between the rotary table and the upper rotary plate; This is a rotation processing apparatus for a square substrate in which the outer periphery of a flat processing space is opened to enable the scattering and outflow of surplus processing liquid, and in the vicinity of the corner of the substrate on the lower side of rotation on each side of the square substrate, 1. A rotational processing apparatus for a square substrate, characterized in that a partition wall for preventing processing liquid mist from flowing into a gap below the substrate is erected on the rotating table. (2) A rotary table whose size exceeds the outer diameter of a rectangular substrate and rotates the substrate in a fixed direction while positioning and supporting the substrate horizontally at small intervals; an upper rotary plate that is arranged in parallel with a small interval, has a size that exceeds the outer diameter of the substrate, and is rotated integrally with the rotary table, and is formed between the rotary table and the upper rotary plate; This is a rotational processing device for a square substrate in which the outer periphery of a flat processing space is opened to enable the scattering and outflow of surplus processing liquid. 1. A rotational processing apparatus for a square substrate, characterized in that a pair of partition walls for preventing processing liquid mist from flowing into a gap below the substrate are erected on the rotating table.