JPH0851061A - Method and device for formation of coating film - Google Patents

Abstract

PURPOSE:To decrease the consumption of a coating solution and to form a coating film of uniform thickness by a method wherein, after a solution has been applied to one surface of a substrate, a coating solution is supplied, the substrate is rotated at a first rotational speed, then, after the substrate has been sealed in a treatment container, the treatment container and the substrate are rotated at a second rotational speed. CONSTITUTION:A substrate G is rotated at low speed by the rotary driving of a spin chuck 10, and a coating solution A is dripped on the surface of the substrate from the solution feeding nozzle 40 located above the center part of the substrate G. Then, the spin chuck 10 is rotated at about 1000rpm, and at the same time, a coating solution B is dripped from a resist solution feeding nozzle 50a to the center part of the solution film on the surface of the substrate. At this time, the drying time of the solution A is computed by a testing. Then, after stopping the feeding of the resist solution, the substrate G is sealed in a rotating cup 12 by putting a cover 16 on the upper aperture 12a of the rotating cup 12. Under the above-mentioned state, the spin chuck 10 and the cup 12 are rotated at about 1350rpm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating film formation for forming a liquid coating film of a solvent such as a resist film on a coating body such as an LCD substrate or a layer formed thereon. The present invention relates to a method and an apparatus thereof.

[0002]

As is well known, in the field of semiconductor technology,
When selectively etching the semiconductor layer, the insulator layer, and the electrode layer formed on the LCD substrate into a predetermined pattern,
As in the case of a semiconductor wafer, a resist film is formed on the surface of the layer as a mask for the pattern portion.

For example, as a method of forming a resist film, a rectangular LCD substrate (hereinafter referred to as a substrate) is mounted and fixed on a mounting table disposed in the processing container, and the opening of the processing container is covered. Closing with the body, rotating the processing container and the mounting table, for example, a resist solution consisting of a solvent and a photosensitive resin is dropped on the central portion of the upper surface of the substrate, and the resist solution is applied to the rotational force and centrifugal force of the substrate. There is known a method in which the coating is applied by diffusing in a spiral shape from the central part of the substrate toward the peripheral part.

In this method, the solvent in the resist solution evaporates in the process in which the resist solution diffuses from the central position of the substrate toward the peripheral portion. For this reason, the viscosity of the resist liquid varies in the direction of diffusion, and the thickness of the formed resist film differs between the central portion and the peripheral portion. Further, since the peripheral speed of the substrate is much higher at the outer peripheral portion than at the center position, the amount of scattering is large. That is, there was a limit to uniform coating.

Therefore, for example, a method of controlling the temperature of the resist solution or filling the same solvent as that used in the resist solution in the atmosphere for forming the resist film to suppress the evaporation of the solvent in the resist solution, or the resist solution A method of dropping the solvent of the resist solution on the surface of the substrate before coating can be considered.

[0006]

However, the former, that is, the temperature adjustment of the resist solution or the same solvent as that used in the resist solution is filled in the atmosphere for forming the resist film to suppress the evaporation of the solvent in the resist solution. In the method, the amount of the resist solution used is large, and for example, only a few% of the applied amount of the resist solution contributes to the actual formation of the resist film. Moreover, since the amount of the resist solution is large, the resist solution spills over to the back surface of the corner portion of the substrate, and the resist solution adhering to the back surface of the substrate corner portion is dried, which causes the generation of particles. In the latter case, that is, by dropping the solvent of the resist solution on the substrate surface before applying the resist solution,
Due to the homogeneity of the solvent itself on the substrate and the difference in the dried state, uniform coating is difficult and the above problems cannot be solved sufficiently.

The present invention has been made in view of the above circumstances, and a method of forming a coating film which requires a small amount of a coating liquid such as a resist liquid and can form a coating film having a uniform thickness, and a method thereof. The purpose is to provide a device.

[0008]

In order to achieve the above object, a method of forming a coating film according to the present invention comprises rotating a substrate contained in a processing container together with the processing container and applying a coating liquid onto the entire surface of the substrate. In the method of supplying and forming a coating film, a step of applying a solvent on one surface of the substrate, supplying a predetermined amount of the coating liquid to the substrate, and rotating the substrate at a first rotation speed The step of diffusing over the entire surface, the step of closing the lid of the processing container to seal the substrate in the processing vessel, and the step of closing the lid of the processing container and the substrate at the second rotation speed. And a step of adjusting the thickness of the coating film by rotating the coating film (claim 1).

In the coating film forming method of the present invention, the amount of the coating liquid is set according to the first rotation speed of the substrate (claim 2).

The amount of coating liquid and the number of rotations of the substrate are
The variation in the thickness of the coating film is set to about ± 2% or less of the average film thickness (claim 3).

The solvent can be applied by rotating the substrate (claim 4). In this case, the number of rotations of the solvent application performed by rotating the substrate and the number of rotations different from the first number of rotations and the second number of rotations are set (claim 5).

Further, it is preferable to apply a solvent of a coating liquid as the above solvent (claim 6).

The coating liquid may be supplied onto the substrate at any position, but it is preferable to supply the coating liquid onto substantially the center of the substrate (claim 7).

Further, the coating film forming apparatus of the present invention supports the one surface of the substrate facing upward, rotates the substrate about an axis perpendicular to the one surface of the substrate, and a cup-like shape surrounding the substrate. And a processing container that rotates together with the means for rotating the substrate, a lid that closes the opening of the processing container, a solvent supply unit that supplies the solvent of the coating liquid to the substrate, and a coating liquid that supplies to the substrate. And a coating liquid supply means for performing the above (claim 8).

In the coating film forming apparatus of the present invention, the coating liquid supply means and the coating liquid supply source for containing the coating liquid are connected to each other through the supply pipe, and the supply amount of the coating liquid can be adjusted to the supply pipe. It is preferable to provide a pump means (Claim 9). In this case, as the pump means, for example, one having a bellows pump and a stepping motor for expanding and contracting the bellows pump so that the coating liquid is supplied by the bellows pump can be used, and a diaphragm pump can be used. Of course, it is also possible to discharge by pressure feeding without using a pump.

Further, it is preferable to provide a temperature adjusting means in at least one of the solvent supplying means and the coating liquid supplying means (claim 10).

Further, it is possible to provide a lid moving means for movably supporting the lid for closing the opening of the processing container between the closed position of the processing container and the standby position separated from the processing container. (Claim 11).

Further, a solvent supply means that supports and supports at least one of the solvent supply means and the coating liquid supply means,
A means for supporting the coating liquid supply means so as to be movable between a supply position above the substrate and a standby position deviated from the supply position can be provided (claim 12).

[0019]

According to the present invention by the above-mentioned technical means, after the solvent of the coating liquid is applied to one surface of the substrate and diffused, a predetermined amount of the coating liquid is supplied to almost the central portion of the substrate, Rotate at 1 rpm to spread over the whole surface of the substrate,
Then, after closing the lid of the processing container and sealing the substrate in the processing container, the processing container and the substrate of which the lid is closed are rotated at the second rotation speed to adjust the film thickness of the coating film. . This makes it possible to supply the coating liquid in an appropriate mixing ratio with respect to the solvent, reduce the amount of the coating liquid used, and prevent the coating liquid from flowing around to the back surface of the corner portion of the substrate. Further, it is possible to form a coating film having a uniform thickness by making the viscosity of the coating liquid uniform by the contact between the solvent and the coating liquid.

[0020]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Here, a case where the coating film forming method and the coating film forming apparatus of the present invention are applied to a method and a forming apparatus for a resist film on an LCD (liquid crystal display) substrate (glass substrate) will be described.

As shown in FIG. 1, the coating film forming apparatus of the present invention is a rotator for sucking and holding a rectangular substrate, which is an object to be coated, for example, an LCD substrate G (hereinafter referred to as a substrate) in a horizontal state by vacuum suction. For example, the spin chuck 10 and a processing chamber 1 that surrounds the upper and outer peripheral portions of the spin chuck 10.
1 is a cup-shaped processing container 12 having an open upper portion.
(Hereinafter, referred to as a rotary cup), a lid body 16 that is removably attached (removed) to the opening 12a of the rotary cup 12,
A robot arm 20 as a lid moving means for moving the lid 16 to a closed position and a standby position, a hollow ring-shaped drain cup 14 arranged so as to surround the outer peripheral side of the rotary cup 12, and a spin chuck 10. And a drive motor 21 which is a means for rotating the rotary cup 12, a supply nozzle 40 (solvent supply means) for the solvent (solvent) A of the coating liquid and a coating liquid which are configured to be movable above the spin chuck 10. A nozzle head 60 in which the supply nozzle 50 (coating liquid supply means) for supplying the resist solution B is brought close to and integrally attached, and a scanning mechanism which is a moving means for gripping the nozzle head 60 and moving it between the nozzle head standby position and the substrate upper position. 70 and.
The solvent A and the resist solution B flowing through the solvent supply path and the resist solution supply path from the nozzles 40 and 50, respectively.
A temperature adjusting mechanism 61 for circulating and supplying the temperature adjusting liquid C for setting the temperature to a preset temperature (for example, 23 ° C.) is provided.

The spin chuck 10 can be driven in accordance with a preset program, and can be rotated (rotated) in the horizontal direction via a rotary shaft 22 which is rotated by the drive of a drive motor 21 whose rotational speed can be varied. Further, it can be moved in the vertical direction by driving an elevating cylinder 23 connected to the rotary shaft 22. In this case, the rotary shaft 22 has a bearing 25 on the inner peripheral surface of the fixed collar 24.
It is slidably connected to a spline bearing 27 fitted to the inner peripheral surface of a rotating inner cylinder 26a rotatably mounted via a. A driven pulley 28a is mounted on the spline bearing 27, and the driven motor 28 is attached to the driven pulley 28a.
A belt 29a is stretched between the drive shaft 21a and a drive pulley 21b mounted on the drive shaft 21a. Therefore, the rotation of the rotary shaft 2 via the belt 29a by the drive of the drive motor 21.
2 rotates to rotate the spin chuck 10. Also,
The lower side of the rotary shaft 22 is arranged in a cylinder body (not shown), and the rotary shaft 22 is arranged in the cylinder body by the vacuum seal portion 3
It is connected to the elevating cylinder 23 via 0, and the rotating shaft 22 can be moved in the vertical direction by driving the elevating cylinder 23.

The rotary cup 12 has the fixed collar 2
4 is attached to the outer peripheral surface of the rotary cup 4 via a bearing 25b and a connecting cylinder 31 fixed to the upper end of the rotating outer cylinder 26b, and between the bottom 12b of the rotary cup 12 and the lower surface of the spin chuck 10. A bearing 32 having a sealing function is interposed therebetween to be rotatable relative to the spin chuck 10. The drive from the drive motor 21 is transmitted to the rotary cup 12 by the driven pulley 28b attached to the rotary outer cylinder 26b and the belt 29b that is stretched around the drive pulley 21b attached to the drive motor 21. Is rotated. In this case, since the diameter of the driven pulley 28b is formed to be the same as the diameter of the driven pulley 28a mounted on the rotating shaft 22, and the belts 29a and 29b are wound around the same drive motor 21.
The rotating cup 12 and the spin chuck 10 rotate in the same direction.
The fixed collar 24, the rotating inner cylinder 26a, and the rotating outer cylinder 2
A labyrinth seal portion 33 is formed on the surface facing 6b to prevent dust from entering the rotary cup 12 from the lower drive system during rotation processing (see FIG. 3).

The rotary cup 12 has a side wall 12c formed with a tapered surface 12e having a diameter reduced upward,
An inward flange 12d is formed from the upper end of the side wall 12c toward the inner side. Further, air supply holes 34 are formed in the upper peripheral portion of the rotary cup 12, that is, the inward flange 12d at appropriate intervals in the circumferential direction, and exhaust gas is provided at an appropriate circumferential position on the lower peripheral portion, that is, the lower side of the side wall 12c. A hole 35 is provided. By providing the air supply hole 34 and the exhaust hole 35 in this manner, when the rotary cup 12 rotates, the air flowing from the air supply hole 34 into the processing chamber 11 flows from the exhaust hole 35 to the outside, so that the rotation cup 12 rotates. Sometimes it is possible to prevent negative pressure in the processing chamber 11,
It is possible to easily open the lid body 16 without requiring a large force when releasing the lid body 16 from the rotary cup 12 after the processing.

On the other hand, an annular passage 14a is provided inside the drain cup 14, and exhaust gas connected to an exhaust device (not shown) is provided at appropriate locations (for example, four locations in the circumferential direction) on the outer peripheral wall of the annular passage 14a. A port 36 is provided, and a radial exhaust passage 37 that communicates with the exhaust port 36 is formed in the upper portion on the inner peripheral side of the drain cup 14 (see FIG. 1). In this way, the exhaust port 3 is provided on the outer peripheral portion of the drain cup 14.
6 is provided, and an exhaust passage 37 communicating with the exhaust port 36 is formed in the upper portion on the inner peripheral side of the drain cup 14, so that the centrifugal force scatters in the process chamber 11 during the rotation process and the drain passes through the exhaust hole 34. The mist that has flowed into the cup 14 can be prevented from rising to the upper side of the rotary cup 12 and discharged from the exhaust port 36 to the outside.

The annular passage 14a has a drain cup 14a.
The outer wall 14b standing up from the bottom of the drain cup 14 and the inner wall 14c hanging from the ceiling of the drain cup 14 are detoured so that exhaust can be performed uniformly.
Drain holes 14e are provided in the bottom portion 14d located between b and the inner wall 14c at appropriate intervals in the circumferential direction.

A tapered surface 14f having a diameter reduced upward is formed on the inner peripheral surface of the drain cup 14 so as to be close to the tapered surface 12e of the rotary cup 12, and the tapered surface 12e of the rotary cup 12 is formed. And a tapered surface 14f of the drain cup 14 forms a minute gap. In this way, by forming the taper-shaped minute gap that expands downward, the rotary cup 1 is rotated when the rotary cup 12 is rotated.
A pressure difference is induced from the peripheral speed difference between the upper and lower sides of the minute gap between the drain cup 14 and the drain cup 14, and this pressure difference causes the air flow from the upper side to the lower side of the minute gap in the outer peripheral portion of the rotary cup 12. It is possible to prevent the exhaust mist in the drain cup 14 from scattering outside the rotary cup 12 through the minute gap.

Further, even if there is a mist that is directed upward through the minute gap and is scattered outside the rotary cup 12, it is sucked by the exhaust passage 37 and discharged into the drain cup 14 from the exhaust port 36.

In the above embodiment, the case where the drain cup 14 is arranged so as to surround the outer peripheral side of the rotary cup 12 has been described, but the drain cup 14 does not necessarily have to be arranged on the outer peripheral side of the rotary cup 12. , Rotating cup 1
You may arrange | position on the lower part side of 2.

The lid 16 must be fixed to the opening 12a of the rotary cup 12 and rotated integrally during the rotation process. Therefore, as shown in FIG. 4, the fixing pin 17a protruding above the rotary cup 12 and the fixing pin 17a
The fitting recess 17b that fits into the
6 is fixed to the rotating cup 12. In this case, the top of the fixing pin 17a is formed into a spherical shape to reduce dust generated by contact with the fitting recess 17b. The fixed pin 17a does not necessarily need to project to the rotary cup side, and the fixed pin 17a may project to the lid side and the fitting recess 17b may be provided on the rotary cup side. Further, the inside of the fitting recess 17b may be connected to a suction means (not shown) so that dust generated by the contact between the fixing pin 17a and the fitting recess 17b can be discharged to the outside.

When the lid 16 is opened and closed, as shown in phantom in FIG. 1, the robot arm 20 is inserted under the bulging head 18 projecting from the upper surface of the lid 16, and the bulging head is bulged. This can be performed by engaging the locking pin 20a protruding from the robot arm 20 with the locking groove 18a provided in the portion 18 and then moving the robot arm 20 up and down. The locking groove 18a of the bulging head 18 and the locking pin 20a of the robot arm 20 are aligned when the lid 16 is opened, and the fixing pin 17a when the lid 16 is closed.
The position of the fitting recess 17b can be adjusted by controlling the rotation angle of the drive motor 21 formed by a servomotor or the like.

In the above embodiment, the lid 16 and the rotating cup 1
The case where the fixing pin 17a and the fitting recess 17b are fixed to each other has been described, but it is not always necessary to have such a structure, and the lid body 16 is separately provided by using a pressing mechanism.
If is fixed to the rotating cup 12, it is possible to prevent dust from being generated when the lid 16 is opened and rattling of the lid 16 during rotation processing.

A baffle plate (not shown) formed at an intermediate position between the lid 16 and the substrate G by a perforated plate having a size larger than that of the substrate G attached to the lid 16 at the central portion. ) Can also be arranged. By arranging the baffle plate in this way, the processing chamber 11 can be more reliably operated during the coating process.
It is possible to prevent the generation of turbulent flow inside.

On the other hand, the solvent supply nozzle 40 is connected to a solvent tank 43 through a solvent supply tube 41 which is a solvent supply path and an opening / closing valve 42, and nitrogen (N ₂ ) gas supplied into the solvent tank 43 is supplied. By controlling the pressurization of the solvent A, the solvent A in the solvent tank 43 can be supplied onto the substrate G in a predetermined amount for a predetermined time.

The resist solution supply nozzle 50 is connected to a resist solution tank 52 (coating solution supply source) for containing the resist solution B via a resist solution supply tube 51 which is a resist solution supply passage. This tube 51 has a suck back valve 53, an air operation valve 54,
A bubble removing mechanism 55 for separating and removing bubbles in the resist liquid B, a filter 56, and a bellows pump 57 are sequentially provided. The bellows pump 57 is capable of expanding and contracting under the control of the drive unit, and a predetermined amount of resist liquid B is passed through the resist liquid supply nozzle 50 to the substrate G.
It is possible to supply, for example, drip to the central part of the. It is possible to control the supply amount of the resist liquid B which is smaller than the conventional supply amount of the resist liquid B. This drive unit includes a ball screw 58 having a screw whose one end is attracted to one end of the bellows pump, a nut screwed to the screw, and a stepping motor 59 that linearly moves the screw by rotating the nut. It is configured. Specifically, in the case of a substrate of 500 × 600 mm, the inner diameter of the resist solution supply nozzle 50 is set to φ0.5 to φ5 mm, preferably φ3 mm. In this way, by setting the diameter of the nozzle according to the size of the substrate, it is possible to supply a small amount of the resist solution B as long as possible. If the supply time is short, the film thickness is not uniform, and if it is too long, the resist solution does not reach the peripheral portion of the substrate. Here, the smallest possible amount depends on the diameter of the nozzle and the resist solution supply pressure.

In the resist solution supply system constructed as described above, the discharge time of the resist solution is determined by the bellows pump 57.
The stepping motor 59 is controlled by the driving time (control accuracy: ± 2 msec). Further, the discharge amount of the resist liquid is set by the driving operation of the bellows pump 57, for example, the driving time and the driving speed, and the opening / closing operation (ON-OFF operation) of the air operation valve 54 for opening / closing the resist liquid supply passage. It has become. Setting of driving time of the bellows pump 57 and ON / OFF of the air operation valve 54
The operation is automatically controlled by the action of the computer based on a preset program.

The discharge time of the resist solution B is controlled by a variable orifice (not shown) provided in the resist solution supply nozzle 50.
It is also possible to perform the opening and closing operation of. Further, without using the bellows pump 57, the N
It is also possible to supply the resist solution B by pressurizing the ₂ gas, and in this case, the discharge time of the resist solution B can be controlled by adjusting the pressurizing amount of the N ₂ gas.

After sucking the resist solution from the resist solution supply nozzle 50, the suck back valve 53 provided in the resist solution supply system removes the resist solution B remaining on the inner wall of the tip of the resist solution supply nozzle 50 due to surface tension. A valve for returning the resist liquid to the inside of the resist liquid supply nozzle 50, thereby preventing solidification of the residual resist liquid. In this case, in the resist solution supply nozzle 50 that discharges a small amount of the resist solution B, when the resist solution B is pulled back into the resist solution supply nozzle 50 by the negative pressure action of the suck back valve 53 as usual, the air near the tip of the nozzle 50 is also removed. The resist solution B remaining on the tip of the nozzle 50 is also entrained in the nozzle 50, and the residue of the resist solution B enters the nozzle 50, causing the nozzle 50 to be clogged, and the dried resist becoming particles to contaminate the substrate G. In addition, there is a risk that the yield will decrease.

To solve this problem, as shown in FIG. 5A, the nozzle hole 50 of the resist solution supply nozzle 50 is provided.
The wall thickness 50b near the opening is made thicker than that of a. That is, the nozzle 50 has a tubular tip portion and an inverted frustoconical portion that follows the tubular tip portion. Instead, as shown in FIG. 5B, the outer flange 5 is attached to the cylindrical tip portion or opening of the resist solution supply nozzle 50.
By providing 0c, the nozzle 5
It is possible to prevent the entrapment of air near the zero tip.
Further, as shown in FIG. 5C, a small-diameter bent portion 50d extending in a lateral S shape is formed at the vertically extending cylindrical tip of the resist solution supply nozzle 50, and the center of the bent portion 50d is formed. By sucking back to the vicinity, it is possible to prevent air from being entrained in the nozzle tip portion in the same manner.

The temperature adjusting mechanism 61 (temperature adjusting means)
As shown in FIG. 6, the temperature adjusting liquid supply passage 62 is provided so as to surround the outer peripheries of the solvent supply tube 41 and the resist supply tube 51, and both ends of the temperature adjusting liquid supply passage 62 are provided at both ends. , A circulation pump 64 provided in each circulation passage 63, and a temperature adjusting liquid C connected in the middle of the circulation passage 63.
The thermo module 65 maintains a constant temperature (for example, constant temperature water). With the temperature adjusting mechanism 61 thus configured, the solvent A flowing in the solvent supply tube 41 and the resist solution B flowing in the resist supply tube 51 can be maintained at a predetermined temperature (for example, about 23 ° C.).

In FIG. 6, the solvent supply nozzle 40 and the solvent supply tube 41 are shown as well as the resist solution supply nozzle 50.
Although the resist solution supply tube 51 and the resist solution supply tube 51 are formed integrally with each other, it is also preferable to form them separately as described in detail below with reference to FIG. 7.

The nozzle head 60 is made of, for example, a stainless steel or aluminum alloy member. A U-shaped hole forming a part of the bypass passage 60b is formed on the upper surface of the jet nozzle 60, and a vertical through hole 60c extending to the lower surface of the nozzle nozzle 60 is formed at the bottom of the hole. Each through hole 60c has an inclined middle portion 60d having a larger diameter as it goes downward and a lower portion 60e having a larger diameter.
A female screw is formed on the inner peripheral surface of 0e. When the nozzles 40 and 50 are mounted on the nozzle head 60 having such a configuration, the cylindrical nozzles 40 and 50 are inserted into the through hole 60c so that the upper portion and the lower portion thereof respectively extend, and the nozzle 40, A sealing member 66 made of a substantially conical synthetic resin having a vertical through hole through which 50 can penetrate is packed in the inclined middle portion 60d, and a mounting screw member 67 having a vertical through hole through which the nozzles 40 and 50 can penetrate is screwed to the lower portion. The seal member 66 is pressed against the inclined inner peripheral surface of the middle portion 60d by being screwed into the 5c. In this way, the nozzles 40, 50
Is attached to the nozzle head 60 in a liquid-tight manner. In this case, by interposing an O-ring 68 between the upper surface of the intermediate portion 5b and the upper surface of the seal member 66 as shown in the drawing, the bypass passage 1
The watertightness between the nozzle 5 and the nozzles 40 and 50 can be further ensured.

A holding pin 6 is provided on the upper surface of one side of the jet nozzle 60.
0a is provided in a protruding manner, and the scan arm 71 that holds the holding pin 60a is moved by the scan mechanism 70 in X, Y directions.
By moving in the (horizontal) and Z (vertical) directions, the spray head 60, that is, the solvent supply nozzle 40 and the resist solution supply nozzle 50 are located between the operating position above the central portion of the substrate G and the standby position above the nozzle standby portion 72. It is designed to be moved selectively.

In this case, four types of jet nozzles 60 are provided according to the type of resist liquid (see FIG. 2). That is, four nozzle heads 60 are prepared in the nozzle standby portion 72, and the resist solution supply nozzles 5 of these nozzle heads 60 are provided.
0 is communicated with a tank containing different resist solutions having different viscosities and the like. In this case, only the resist liquid supply nozzle 50 is provided in each of the jet heads 60, and the solvent supply nozzle 40 is attached to the tip of the scan arm 71 in advance so that it can be commonly used for all the jet heads 60. May be. Further, in this case, a plurality of solvent supply nozzles 40, for example, linear pipes may be provided to supply the solvent from a plurality of locations at a time along the radial direction of the substrate. In this case, nozzles having different discharge diameters may be provided, and the discharge from each nozzle may be arbitrarily controlled in accordance with the magnitude of the discharge flow rate and the change in the discharge flow rate.

A standby portion 46 of the rinse liquid supply nozzle 45 is provided on the side facing the nozzle standby portion 72 (see FIG. 2). Further, by disposing the cleaning nozzle 47 in the connection cylinder 31 which is fixed on the lower side of the rotating cup 12 and does not rotate, the inner surfaces of the rotating cup 12 and the lid 16 can be cleaned. That is, a cleaning nozzle 47 is held by a bracket 48 attached to the rotary shaft 22, and a cleaning liquid supply pipe 49 connected to the cleaning nozzle 47 is provided to the outside through a passage (not shown) provided in the fixed collar 24. By connecting to the cleaning liquid supply source, the spin chuck 10 is lifted to expose the cleaning nozzle 47 from between the spin chuck 10 and the bottom of the rotating cup 12 to rotate the cleaning liquid, as shown by an imaginary line in FIG. Rotating cup 12
And, it can be sprayed on the inner surface of the lid 16.

Next, the procedure for forming a resist film by the coating film forming apparatus having the above-described structure will be described with reference to the flowchart of FIG.

First, the lid 16 of the rotary cup 12 is opened, and the substrate G is moved onto the stationary spin chuck 10 by a transfer arm (not shown). The substrate G is held by the spin chuck 10 by vacuum suction. Support G. Next, the rotation of the spin chuck 10 causes the substrate G to rotate at a lower speed than the steady rotation during processing (rotation speed: 100 to 600 rpm, acceleration: 300 to 500 rp, for example).
m / sec), and the rotating cup 12 is rotated at the same speed. During this rotation, the solvent A of the coating liquid is applied to the surface of the substrate from the solvent supply nozzle 40 of the jet nozzle 60 which is grasped by the scanning mechanism 71 by the scanning mechanism 70 and moved above the central portion of the substrate G, such as ethyl cellosolve acetate (ECA). ) Is supplied for, for example, 26.7 cc for 20 seconds (sec), for example, dropped (step).
This supply means may be a spray. Alternatively, the solvent A may be dropped while the substrate G is stationary without being rotated, and then the substrate G may be rotated. After the solvent A has been supplied for 20 seconds in this way, the supply of the solvent A is stopped (step) while the spin chuck 10 and the rotary cup 12 are rotated at the low rotation speed.

Next, the spin chuck 10 is rotated at high speed (first rotation speed: in the range of 600 to 1000 rpm, for example, 1000 rpm, acceleration: 300 to 600 rpm).
At the same time, the coating liquid, for example, the resist liquid B is supplied from the resist liquid supply nozzle 50a to the central portion on the solvent film on the surface of the substrate for, eg, 5 sec, and, for example, 10 cc is dropped (step). The time at which the solvent A is dried can be determined in advance by experiments. For example, by visually observing the surface of the substrate G, it is not dried while the interference fringes of light are visible, and the interference fringes are not visible when dried, so the time can be known. In this case, at the supply time of 5 seconds, the driving time of the bellows pump 57 described above can be controlled, and the supply amount of the resist solution can be accurately and delicately controlled. In this way, the resist liquid B
Is supplied (dropped) for 5 seconds, the supply of the resist solution B is stopped, and at the same time, the rotations of the spin chuck 10 and the rotating cup 12 are stopped (step).

After stopping the supply of the resist solution and moving the resist solution supply nozzle 50 to the standby position, the robot arm 2
The lid 16 is opened by the upper opening 12 of the rotary cup 12
The substrate G is closed in a and the substrate G is enclosed in the rotary cup 12 (step).

In this way, the opening 1 of the rotary cup 12
In the state where 2a is closed and sealed by the lid body 16, the spin chuck 10 and the rotating cup 12 are rotated (second rotation speed: for example, 1350 rpm, acceleration: 50) for, for example, 15 seconds.
0 rpm / sec) to adjust the thickness of the resist film (step). After the coating process is completed, the spin chuck 10 and the rotary cup 12 are stopped from rotating, the robot arm 20 moves the lid 16 to the standby position, and the transfer arm (not shown) removes the substrate G.
Complete the coating operation.

The coating film forming apparatus according to the present invention configured as described above is used alone as a resist coating apparatus for the LCD substrate G, and is also used by being incorporated in a resist coating / developing processing system for the LCD substrate G described later. can do. The structure of a resist coating / developing system incorporating the coating film forming apparatus of the above embodiment will be described below.

The above resist coating / developing system is
As shown in FIG. 9, a loader unit 9 for loading and unloading the substrate G
0, the first processing unit 91 of the substrate G, and the second processing unit 92 that is connected to the first processing unit 91 via the relay unit 93. The second processing unit 92 has a delivery unit 94.
An exposure device 95 for exposing a predetermined fine pattern to the resist film can be connected via the via.

The loader section 90 has a cassette 96 for accommodating an unprocessed substrate G, a cassette mounting table 98 for mounting a cassette 97 for accommodating the processed substrate G, and a cassette 96 on the cassette mounting table 98. , 97 to substrate G
Substrate loading / unloading tweezers 9 capable of moving and rotating (θ) in horizontal (X, Y) and vertical (Z) directions for loading / unloading
It is composed of 9 and 9.

The first processing section 91 is a transport path 102 for the main arm 80 which is movable in the X, Y and Z directions and is rotatable by θ.
On one side, a brush cleaning device 120 for brush cleaning the substrate G, a jet water cleaning device 130 for cleaning the substrate G with high-pressure jet water, an adhesion treatment device 105 for hydrophobicizing the surface of the substrate G, and a substrate A cooling processing device 106 for cooling G to a predetermined temperature is arranged, and a coating processing device 107 and a coating film removing device 108, which are coating film forming devices of the present invention, are arranged on the other side of the transport path 102.

On the other hand, the second processing section 92 has a main arm 80a capable of moving in the X, Y and Z directions and rotating by the same as the first processing section 91, and the main path 80a of the main arm 80a. A heat treatment device 109 that heats the substrate G before and after applying the resist solution to perform pre-baking or post-baking is arranged on one side, and a developing device 110 is arranged on the other side of the transport path 102a.

Further, the relay portion 93 has a structure in which casters 93d are provided on the bottom surface of a box body 93c having a transfer table 93b on which support pins 93a for supporting the substrate G are erected. The relay unit 93 is pulled out from the first processing unit 91 and the second processing unit 92, and the first processing unit 91
Alternatively, a worker can enter the second processing section 92 to easily perform repairs and inspections.

The delivery section 94 has a cassette 111 for temporarily holding the substrate G, and the cassette 1
Transport tweezers 1 for moving the substrate G in and out of
12 and a transfer table 113 for the substrate G are provided.

In the coating / development processing system configured as described above, the unprocessed substrate G accommodated in the cassette 96 is taken out by the carry-in / take-out tweezers 99 of the loader section 90, and then the first processing section 91. It is delivered to the main arm 80 and then conveyed into the brush cleaning device 120. The substrate G brush-cleaned in the brush cleaning device 120 is subsequently cleaned in the jet water cleaning device 130 with high-pressure jet water. After that, the substrate G is subjected to a hydrophobic treatment by the adhesion treatment device 105 and cooled by the cooling treatment device 106, and then the coating film forming device 107 according to the present invention performs the photoresist treatment by the above-described procedure. A photosensitive film is formed by coating, and then the unnecessary resist film on the side portion of the substrate G is removed by the coating film removing device 108. Therefore, after this, when the substrate G is carried out, the resist film on the edge is removed, so that the resist does not adhere to the main arm 80. Then, after the photoresist is heated by the heat treatment device 109 to be subjected to a baking treatment, a predetermined pattern is exposed by the exposure device 95. And the substrate G after exposure
Is conveyed into the developing device 110, and after being developed with the developing solution, the developing solution is washed away with the rinse solution to complete the developing process.

The developed and processed substrate G is accommodated in the cassette 97 of the loader unit 90, then carried out and transferred to the next processing step.

In the above embodiment, the structure in which the solvent supply nozzle 40 is integrally provided with the resist liquid supply nozzle 50 on the nozzle head 60 has been described, but the present invention is not limited to this, and the embodiment shown in FIG. As shown in the example, the solvent may be supplied by being provided integrally with the nozzle head 46 having the rinse liquid supply nozzle 45.

In this example, a common temperature adjusting mechanism 61 is provided in the solvent supply path and the resist solution supply path (see FIG. 11). The nozzle head 60 and the scan arm 71 of the scan mechanism 70 are integrally formed, and a temperature adjusting liquid supply passage 62 is formed in the nozzle head 60 and the scan arm 71, and the solvent supply tube 41 and the resist liquid supply tube 51 are provided in the supply passage 62. Are connected by piping so that the temperature of the solvent A and the resist liquid B can be adjusted by the same temperature adjusting liquid C. With this configuration, the temperature adjustment mechanism 61
The structure can be simplified, and the solvent A and the resist solution B can be maintained at the same temperature.

The arrangement and configuration of the nozzle head 60 and the nozzles 40, 50 are not limited to the above-mentioned example, and for example, FIG.
2 to 15 may be used. In the example shown in FIG. 12, the solvent supply nozzle 40 is arranged on the outer periphery of the resist solution supply nozzle 50 coaxially therewith. For this reason, the resist solution supply nozzle 50 and the solvent supply nozzle 40 have a double pipe structure, and the tip of the solvent supply nozzle 40 is projected below the tip of the resist solution supply nozzle 50. Of course, the tip of the solvent supply nozzle 40 may be at the same level as the tip of the resist solution supply nozzle 50, or the former may be shorter. Alternatively, the resist solution supply nozzle 50 may be arranged outside the solvent supply nozzle 40. Further, as shown in FIG. 13, the resist liquid supply nozzle 50 and the solvent supply nozzle 4
It is also possible to adopt a mechanism in which 0 and 0 are provided side by side and these discharge ports 69 are common.

As shown in FIG. 14, an annular solvent storage tank 60 formed in the nozzle head 60 and having a discharge port 69 in the center.
The tip of the solvent supply nozzle 40 is inserted into the solvent inside the tank f, and the tip of the resist solution supply nozzle 50 is inserted into the tank 60f.
Alternatively, the tip of the nozzle 50 may be exposed to the atmosphere of the vaporized solvent. In this way, the solvent supply nozzle 40 is attached to the outer periphery of the tip of the resist solution supply nozzle 50.
By disposing the tip of the resist liquid supply nozzle 5
The resist adhering to 0 can be washed with a solvent, and the resist liquid can be prevented from drying.
Generation of particles due to drying of the resist solution can be prevented.

Further, as shown in FIG. 15, the solvent supply nozzle 40 is arranged in parallel along the outer periphery of the resist solution supply nozzle 50.
May be arranged, and the tip of this nozzle 40 may be branched into a plurality, in this example, four. As a result, the solvent is supplied to four locations at once. Preferably, the branch nozzle portions 40a are arranged so as to respectively correspond to the four corners of a rectangle similar to the substrate G, and the solvent is simultaneously supplied to the center of the substrate G at symmetrical positions on a diagonal line. It By doing so, the diffusion of the solvent can be made uniform to some extent on the rectangular substrate.

Next, an example of the resist film forming method of the present invention will be described based on experiments. [Experiment 1] For example, ECA was used as the solvent A, and a fixed amount (for example, 25 cc) of this solvent A was supplied under the conditions of the above step, that is, the rotation speed: 500 rpm, the time: 20 sec, and then the resist solution supply nozzle. An experiment was performed under the following conditions for supplying (dropping) the resist solution B onto the substrate G from 50.

Conditions Discharge (supply) time of resist liquid: 2 sec, 5 sec Rotation speed: 300, 500, 600, 800, 1000 r
pm Substrate G dimensions: 500 × 600 mm As a result of the above Experiment 1, the rotation speed: 600 rpm (strictly speaking,
Discharge rotation speed of 500 to less than 800 rpm), time: 5 s
In ec, when the resist solution B is supplied at 8 cc / sheet, the amount of resist required to coat the entire surface of the substrate G can be minimized (see FIG. 16), and the film thickness profile is as shown in FIG. In addition, the thickness variation (range) of the coating film is 597 angstroms (Å),
It was found that a uniform film thickness of about 600 Å (Å), which is about ± 2% of the average film thickness, can be formed. In addition, changing the rotation speed to 800 rpm and 1000 rpm, 5
When the resist solution B is supplied for sec, the thickness variation (range) of the coating film can be reduced to 412 and 240 angstroms (Å), but the resist amount may be slightly increased to 10 cc / sheet. found.

Experiment 2 Ethyl cellosolve acetate (ECA) was used as the solvent A, the solvent A was supplied under the following conditions, and then the resist solution B was supplied (dripping) from the resist solution supply nozzle 50 onto the substrate G. ) Was performed.

Conditions Resist: TSMR-8900 Viscosity: 15 cp Rotational speed: 300, 500, 800, 1000 rpm Solvent flow rate: 80, 100, 120, 150 cc / min Substrate G dimension: 500 × 600 mm Experiments under the above conditions The results shown in Table 1 were obtained.

[0069]

[Table 1]

As a result of the above experiment 2, as shown in FIG.
It can be seen that the higher the number of revolutions and the higher the flow rate of the solvent per unit time, the shorter the discharge (supply) time will be. Also, from a different point of view, the flow rate x time = actual usage value ,
As shown in FIG. 19, it was found that the higher the rotation speed, the smaller the amount of solvent used.

When the film thickness profile of the coating film was measured based on the above Experiment 2, the results shown in Table 2 were obtained.

[0072]

[Table 2]

As a result of the experiment 2, the rotation speed is 800 rp.
m, solvent flow rate: 150 cc / min, solvent discharge time: 9
sec, solvent amount: 22.5 cc, film thickness variation (range) is 364 angstrom (Å), rotation speed: 1000 rpm, solvent flow rate: 150 cc / mi
When n, solvent discharge time: 8 sec, and solvent amount: 20 cc, the film thickness variation (range) was 582 Å (Å), and it was possible to achieve uniform film thickness.

As the coating liquid, a resist (phenol novolac resin and naphthoquinone diazide ester),
ARC (Anti-reflection film; Anti Reflection)
Coating) can be used. Examples of the solvent include methyl-3-methoxypropionate (MMT, boiling point: 145 ° C., viscosity: 1.1 cps), ethyl lactate (EL, boiling point: 154 ° C., viscosity: 2.6 cps), ethyl-3. -Ethoxypropionate (EEP, boiling point: 17
0 ° C, viscosity: 1.3 cps, ethyl pyruvate (E
P, boiling point: 144 ° C., viscosity: 1.2 cps), propylene glycol monomethyl ether acetate (PGME
A, boiling point: 146 ° C., viscosity: 1.3 cps), 2-heptanone (boiling point: 152 ° C., viscosity: 1.1 cps), cyclohexanone (solvent for ARC) and the like known in this field can be used.

In the above embodiment, the lid 16 of the rotary cup 12 is moved and opened by the robot arm 20 to supply the solvent A supply nozzle 40 and the resist solution B supply nozzle 50.
In the above description, the scanning mechanism 70 moves the substrate G above the center of the substrate G to drop the solvent A and the resist solution B. However, the opening 12a of the rotary cup 12 is dropped with the lid 16 closed. It may be configured to do so.

For example, as shown in FIG. 20, the bulging head portion 18 of the lid 16 is formed in a hollow shape, and the upper end portion of the lid 16 can be closed by the lid 18A. Then, the lid 18A is opened, and the nozzle is swung up by the scanning mechanism 70.
8 above the hollow, that is, above the center of the substrate G,
The solvent A and the resist solution B are dropped.

Further, as shown in FIG.
The lid 16 is rotatably attached to the inside of the nozzle mounting member 18B by a bearing 18C or the like. The nozzles 40, 50 attached to the nozzle mounting member 18B in a state where the opening 12a of the rotary cup 12 is closed by the lid 16.
The solvent A and the resist solution B are dropped from the center of the substrate G.

As described above, the opening 16a is formed in the lid 16.
By dropping the solvent A and the resist solution B in the closed state, the processing throughput is shortened compared to the moving type by the scanning mechanism 70, and the treatment process from the dropping of the solvent A in the sealed state to the end of the coating treatment is performed. It can be realized. For example, a process of rotating the rotary cup 12 while supplying the resist solution B after supplying the solvent A, then stopping the supply of the resist solution B, and rotating the rotary cup 12 can be realized.

In the above embodiment, the case where the coating film forming apparatus according to the present invention is applied to the resist coating apparatus for the LCD substrate has been described. However, the coating film forming apparatus for the object other than the LCD substrate, such as a semiconductor wafer or a CD, is to be processed. Needless to say, the present invention can also be applied to a polyimide-based coating liquid (PIQ) other than resist, a coating liquid (SOG) containing a glass agent, and the like.

[0080]

As described above, according to the present invention, after coating the solvent on one surface of the substrate, a predetermined amount of the coating liquid is supplied onto the substrate and rotated at the first rotation speed. Then, the substrate is diffused over the entire surface, the lid is closed in the processing container, the substrate is sealed in the processing container, and then the processing container and the substrate with the lid closed are rotated at the second rotation speed. By adjusting the film thickness of the coating film, it is possible to supply the coating liquid with an appropriate mixing ratio to the solvent, reduce the amount of coating liquid used, and sneak the coating liquid to the back surface of the corner of the substrate. Can be prevented. Further, it is possible to form a coating film having a uniform thickness by making the viscosity of the coating liquid uniform by the contact between the solvent and the coating liquid.

[Brief description of drawings]

FIG. 1 is a schematic view of a coating film forming apparatus for carrying out a coating film forming method according to an embodiment of the present invention.

FIG. 2 is a schematic plan view of the coating film forming apparatus shown in FIG.

FIG. 3 is an enlarged cross-sectional view of a main part of a coating film forming apparatus.

FIG. 4 is a partial cross-sectional perspective view showing a processing container and a lid according to the present invention.

FIG. 5 is a cross-sectional view showing different modified examples of the tip portion of the resist liquid supply nozzle according to the present invention.

FIG. 6 is an enlarged perspective view showing a nozzle head used in a coating film forming apparatus.

FIG. 7 is a cross-sectional view of a jet nozzle.

FIG. 8 is a flow chart for explaining a method for forming a resist film using a coating film forming apparatus.

FIG. 9 is a perspective view schematically showing an entire resist coating / developing system to which a coating film forming apparatus is applied.

FIG. 10 is a perspective view showing a modified example of the jet nozzle.

FIG. 11 is a cross-sectional view showing a modified example of the jet nozzle.

FIG. 12 is a cross-sectional view showing another modified example of the nozzle assembly of the jet nozzle.

FIG. 13 is a cross-sectional view showing still another modified example of the nozzle assembly of the jet nozzle.

FIG. 14 is a cross-sectional view showing still another modified example of the nozzle assembly of the jet nozzle.

FIG. 15 is a perspective view showing a modified example of a nozzle assembly and an LCD substrate that is a coating film forming body.

FIG. 16 is a graph showing the relationship between the number of rotations of the substrate and the amount of resist required to coat the entire surface of the substrate.

FIG. 17 is a graph showing a variation range of the thickness of the resist film from the relationship of the rotation speed of the substrate.

FIG. 18 is a graph showing the relationship between the discharge time of the resist liquid and the rotation speed of the substrate.

FIG. 19 is a graph showing the relationship between the amount of solvent used and the rotation speed of the substrate.

FIG. 20 is an explanatory diagram showing another example of the droplet dropping method.

FIG. 21 is a configuration diagram showing still another example of a droplet dropping method.

[Explanation of symbols]

10 Spin Chuck 12 Rotating Cup (Processing Container) 16 Lid Body 20 Robot Arm (Lid Body Moving Means) 21 Drive Motor 40 Solvent Supply Nozzle (Solvent Supply Means) 50 Resist Liquid Supply Nozzle (Coating Liquid Supply Means) 52 Resist Liquid Tank ( Coating liquid supply source) 57 Bellows pump 59 Stepping motor 70 Scan mechanism (moving means of solvent / coating liquid supply means) G LCD substrate (substrate) A solvent B resist liquid (coating liquid)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenji Sekiguchi, Kenji Sekiguchi 2655 Tsukyu, Kikuyo-cho, Kikuchi-gun, Kumamoto Tokyo Electron Kyushu Co., Ltd. Kumamoto Plant (72) Inventor Omori Den 2-3-1, Nishishinjuku, Shinjuku-ku, Tokyo No. Tokyo Electron Limited

Claims (12)

[Claims] 1. A method for forming a coating film by rotating a substrate housed in a processing container together with the processing container and supplying a coating liquid onto the one surface of the substrate, wherein a solvent is applied onto the one surface of the substrate. A step of supplying a predetermined amount of the coating liquid to the substrate, rotating the substrate at a first rotation speed to diffuse the coating liquid over the entire one surface of the substrate, and closing the lid of the processing container. Coating comprising the steps of enclosing the substrate in a processing container, and rotating the processing container and the substrate with the lid closed at a second rotation speed to adjust the film thickness of the coating film. Film forming method. 2. The coating film forming method according to claim 1, wherein the amount of the coating liquid is set according to the first rotation speed of the substrate. 3. The coating film forming method according to claim 2, wherein the amount of the coating liquid and the number of rotations of the substrate are set so that the fluctuation of the coating film thickness is about ± 2% or less of the average film thickness. A coating film forming method, characterized in that 4. The coating film forming method according to claim 1, wherein the solvent is coated by rotating the substrate. 5. The coating film forming method according to claim 4, wherein the rotation number of the solvent coating performed by rotating the substrate is different from the first rotation number and the second rotation number. Forming method. 6. The method for forming a coating film according to claim 1, wherein the solvent of the coating liquid is applied as the solvent. 7. The coating film forming method according to claim 1, wherein the coating liquid is supplied onto substantially the center of the substrate. 8. A means for supporting one surface of the substrate upward and rotating the substrate about an axis perpendicular to the one surface of the substrate, and a means for rotating the substrate having a cup shape surrounding the substrate. The processing container includes a rotating processing container, a lid that closes the opening of the processing container, a solvent supply unit that supplies a solvent of the coating liquid to the substrate, and a coating liquid supply unit that supplies the coating liquid to the substrate. A coating film forming apparatus characterized by the above. 9. The coating film forming apparatus according to claim 8, wherein the coating liquid supply means and the coating liquid supply source containing the coating liquid are communicated with each other through a supply pipe, and the supply amount of the coating liquid is supplied to the supply pipe. A coating film forming apparatus, characterized in that the adjustable pump means is provided. 10. The coating film forming apparatus according to claim 8, wherein temperature adjusting means is provided in at least one of the solvent supplying means and the coating liquid supplying means. 11. The coating film forming apparatus according to claim 8, wherein a lid body that movably supports a lid body that closes the opening between a closed position of the processing container and a standby position separated from the processing container. An apparatus for forming a coating film, which comprises: 12. The coating film forming apparatus according to claim 8, wherein at least one of the solvent supply unit and the coating liquid supply unit is supported, and the supported solvent supply unit and coating liquid supply unit are provided at a supply position above the substrate. An apparatus for forming a coating film, comprising means for movably supporting a standby position apart from a supply position.