JP2001068402A - Board treatment equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent mist of solvent from leaking outside a waiting pot when the solvent is predispensed in the waiting pot. SOLUTION: A porous buffer member 45 formed of a metal mesh, a filter, etc., is arranged at a position in a waiting pot 40 where solvent from a nozzle 10 for spraying solvent is received. While the solvent from the nozzle 10 is captured by the buffer member 45, high speed draft passes the buffer member 45 and is discharged via an exhaust vent 44. By capturing the spouted solvent with the buffer member 45, generation of mist of the solvent in the waiting pot 40 is restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer, a glass substrate for a photomask, a glass substrate for a liquid crystal display, a substrate for an optical disk (hereinafter simply referred to as "substrate"), and the like. Spin On Glass, also known as a silica-based film forming agent) liquid, a photoresist solution, a substrate processing apparatus suitably used as a pretreatment for forming a coating film of a coating liquid such as a polyimide resin, and particularly a substrate surface. The present invention relates to an apparatus for spraying a solvent on a substrate.

[0002]

2. Description of the Related Art Conventionally, if the wettability between a coating solution such as a photoresist solution used in a semiconductor manufacturing process and a substrate on which a coating film is formed is poor, uniformity of the film formation is impaired, or It is known that various problems occur, such as an increase in the amount of wasted coating solution scattered from the substrate. Then, in order to improve the wettability between the coating liquid and the substrate, there is a method disclosed in, for example, JP-A-10-149964. According to this method, a solvent is sprayed on the substrate surface while rotating the substrate to wet the substrate surface with the solvent, and then a coating liquid is supplied to the substrate to form a coating film on the substrate. When the surface of the substrate is wet with the solvent, the wettability of the coating liquid to the substrate is improved, so that the uniformity of the film formation is improved and the amount of the coating liquid used can be reduced.

[0003]

However, the above-mentioned conventional method has the following problems. That is, when the distribution state of the solvent that has been sprayed and adhered to the substrate is non-uniform, for example, when an excessive solvent is supplied to a part of the substrate, or when a part of the substrate is not wet with the solvent, On the contrary, there is a problem that the uniformity of the film formation of the coating solution is impaired.

[0004] The present inventor has studied factors that make the distribution of the solvent non-uniform in order to solve the above problems. As a result, it has been found that if there is a variation in the liquid level of the solvent remaining in the solvent spray nozzle, the distribution of the solvent attached to the substrate becomes uneven or uneven. Hereinafter, description will be made with reference to FIG. FIG. 1A is a cutaway front view showing the structure of a solvent spray nozzle, and FIG. 1B is a cutaway side view.

[0005] The solvent spray nozzle 10 comprises a gas-liquid mixing section 12 connected to a solvent supply pipe 11 and an injection section 13 connected to the gas-liquid mixing section 12.
The gas-liquid mixing section 12 includes a solvent flow path 12a that communicates with the solvent supply pipe 11, and a gas flow path 12b that intersects the solvent flow path 12a at right angles. The injection unit 13 has a hemispherical shape, and has a flat diffusion channel 13a formed in a central portion thereof, which communicates with the solvent flow channel 12a and expands in a fan shape downward.

In such a solvent spray nozzle 10, when a gas such as nitrogen gas is supplied into the gas-liquid mixing section 12 from the gas flow path 12b at a high speed, the solvent flow path 12
a is mixed with the gas, and the solvent L
Becomes a mist and is ejected from the diffusion channel 13a of the ejection unit 13 (see FIGS. 5A and 5B). However, if the solvent and the high-speed gas are not supplied to the solvent spray nozzle 10 in a standby state, the level of the solvent L in the solvent flow path 12a decreases as shown in FIG. 5C. When the high-speed gas is supplied in this state, the solvent flow path 12a and the gas flow path 12a
The solvent L ′ that hangs down in the solvent flow path 12a below the position where the b intersects is unlikely to be in the form of a mist, and is pushed out from the jetting unit 13 in the form of droplets and adheres to the substrate, and the solvent Make the distribution uneven.

On the other hand, when the solvent to be used is volatile, if the nozzle 10 is left for a long time, the level of the solvent L retreats in the solvent flow path 12a due to the evaporation of the solvent, and the supply amount of the solvent fluctuates. Problem. As a result of the variation in the supply amount of the solvent, the uniformity of the film formation of the coating solution is impaired. This state becomes remarkable when the standby time from the time when the spraying of the solvent is stopped to the time when the spraying is started becomes relatively long. When the solvent application is performed with a small amount even if the fluctuation amount of the liquid level is small, the ratio of the fluctuation amount of the solvent to the total amount of the solvent increases, and thus there is a problem that the dispersion of the process increases.

In order to eliminate the above-mentioned adverse effects caused by fluctuations in the liquid level of the solvent remaining in the solvent spray nozzle, the present inventor has proposed that the solvent spray nozzle be used immediately before spraying the solvent onto the substrate. It was considered that a high-speed air flow was supplied to discharge the solvent remaining in the solvent spray nozzle (solvent L ′ in FIG. 5C), and to level the solvent level in the solvent spray nozzle. Alternatively, even when the standby time of the nozzle is long, the liquid level of the solvent in the solvent spray nozzle was considered to be uniform. Hereinafter, such preliminary discharge of the solvent is referred to as “solvent pre-dispense”.

When the solvent is pre-dispensed in the processing atmosphere of the substrate, the mist of the solvent may be scattered and contaminate the substrate. Thus, the present inventor has devised a standby pod 15 for pre-dispensing a solvent as shown in FIG. 6, but the following problems to be solved have become apparent.
That is, when the solvent remaining in the solvent spray nozzle 10 is vigorously discharged into the standby pod 15 by the high-speed gas, the high-speed gas containing the solvent collides with the inner wall 15a of the standby pod 15 and the solvent is mist M And may leak from the standby pod 15 to contaminate the substrate.

The present invention has been made in view of such circumstances, and provides a substrate processing apparatus in which a solvent mist does not leak out of a standby pod when a solvent is pre-dispensed in the standby pod. The purpose is to do.

[0011]

The present invention has the following configuration in order to achieve the above object. That is, according to the first aspect of the invention, before spraying a solvent onto a substrate and performing a required process, a solvent spray nozzle is inserted into a standby pod, and a solvent remaining in the solvent spray nozzle is discharged in advance. In the substrate processing apparatus configured as described above, the standby pod includes a nozzle insertion port for inserting a solvent spray nozzle into the standby pod, and is inserted into the nozzle insertion port within the standby pod. In the position to receive the solvent sprayed from the sprayed nozzle for solvent,
A porous buffer member is provided.

According to a second aspect of the present invention, in the substrate processing apparatus of the first aspect, the buffer member is formed of a mesh made of a corrosion-resistant metal.

According to a third aspect of the present invention, in the substrate processing apparatus of the first aspect, the buffer member is formed of a porous filter.

According to a fourth aspect of the present invention, in the substrate processing apparatus according to any one of the first to third aspects, the apparatus further supplies a rotation holding mechanism for rotating and holding the substrate and a coating liquid to the substrate. And a coating liquid supply mechanism.

[0015]

The operation of the present invention is as follows. According to the first aspect of the present invention, when the solvent spray nozzle is inserted into the standby pod and the solvent is jetted, the airflow containing the solvent is received by the buffer member. The solvent is captured by the cushioning member while the air stream containing the solvent passes through the porous cushioning member. Therefore, since the generation of the mist of the solvent in the standby pod is suppressed as much as possible, the mist does not leak to the outside from the standby pod.

According to the second and third aspects of the present invention, when an air stream containing a solvent passes through a corrosion-resistant metal mesh (claim 2) or a filter (claim 3),
Solvents are each captured.

According to the fourth aspect of the invention, the solvent is pre-dispensed in the standby pod, the solvent is sprayed while rotating the substrate, and the substrate is wetted. The coating liquid is supplied to the substrate to form the coating film. The forming process is performed continuously.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. <First Embodiment> FIG. 1 is a view schematically showing the overall structure of a substrate processing apparatus according to the present invention, and FIG. 2 is a sectional view of a standby pod.

The substrate processing apparatus according to the present embodiment is an apparatus for spin-coating a photoresist liquid on a semiconductor wafer (hereinafter, referred to as a “substrate”) W. In order to ensure the wettability between the substrate W and the photoresist liquid, a solvent is sprayed on the substrate W.

The apparatus of this embodiment includes a spin chuck 20 for holding a substrate W by suction in a horizontal position,
0 and a motor 22 having an output shaft 21 connected thereto. The spin chuck 20 and the motor 22 correspond to a rotation holding mechanism in the present invention. A cup 23 is provided around the spin chuck 20, and a solvent or a photoresist liquid scattered from the substrate W during processing is collected by the cup 23.

Further, the apparatus of the present embodiment includes a solvent spray nozzle 10 for spraying a solvent to the substrate W and a photoresist discharge nozzle 2 for discharging a photoresist liquid to the substrate W.
5 is provided. This photoresist discharge nozzle 2
Reference numeral 5 corresponds to a coating liquid supply mechanism in the present invention. As described with reference to FIG. 5, the solvent spray nozzle 10 atomizes and ejects the solvent by the high-speed airflow supplied to the nozzle tip. This solvent is used as a main solvent of a processing solution (a photoresist solution in this embodiment), for example, ECA
(Ethylene glycol monoethyl ether acetate) or MAK (methyl-2-n-amyl ketone). At the base ends of the nozzles 10 and 25, lifting drive mechanisms 26 and 27 for moving the nozzles 10 and 25 up and down are provided.
And turning drive mechanisms 28 and 29 for turning the nozzles 10 and 25, respectively. During processing, each nozzle 1
The nozzles 0 and 25 are moved up and down and swirled to move the tip of each nozzle above the center of rotation of the substrate W. Motor 2 described above
2, lifting drive mechanisms 26 and 27, and turning drive mechanism 2
8 and 29 are controlled by the control unit 30. Control unit 3
0 controls each mechanism in the control order stored in the memory 31 in advance.

A standby pod 40 for pre-dispensing a solvent, which is a main part of the present embodiment, is provided beside the cup 23. Hereinafter, the configuration of the standby pod 40 will be described with reference to FIG. The standby pod 40 has an outer container 41, and a nozzle insertion port 42 for inserting the solvent spray nozzle 10 into the standby pod 40 is opened on the upper surface of the outer container 41. On the bottom of the outer container 41, a standby pod 4 is provided.
A drain port 43 for discharging the solvent spouted in 0;
An exhaust port 44 for exhausting the inside of the standby pod 40 is connected to each other. Note that a small amount of solvent is ejected in the standby pod 40, and most of the solvent is vaporized and discharged from the exhaust port 44 due to the volatility of the solvent. Therefore, the drain port 43 is not necessarily provided.

Further, a porous buffer member 4 is provided in the standby pod 40 at a position for receiving the solvent sprayed from the solvent spray nozzle 10 inserted from the nozzle insertion port 42.
5 are provided. The cushioning member 45 of the present embodiment is formed of a mesh made of a corrosion-resistant metal such as stainless steel, and is formed in a cylindrical shape with only the upper surface opened. A buffer member 45 is attached and fixed to the ceiling surface of the outer container 41 so as to surround the solvent spray nozzle 10 inserted from the nozzle insertion port 42. As the metal mesh forming the buffer member 45, a mesh having a fine mesh enough to capture the solvent but to allow the airflow to pass through is used from the high-speed airflow including the solvent injected from the solvent spray nozzle 10. Further, the metal mesh is not limited to one layer, and it is also preferable to form the buffer member 45 by laminating a plurality of layers.

Next, the operation of the above embodiment will be described. In the standby state, the solvent spray nozzle 10 is inserted into the standby pod 40. At this time, standby pod 4
The inside of 0 is weakly sucked and exhausted by an exhaust device (not shown) through an exhaust port 44. When the substrate W to be processed is placed on the spin chuck 20, the solvent is pre-dispensed in the standby pod 40 as follows. That is, while the supply of the solvent to the solvent spray nozzle 10 is stopped, the nitrogen gas is supplied to the nozzle 10 at a high speed. Then, as shown in FIG. 5C, the solvent L ′ hanging down in the solvent flow path 12a in the nozzle 10 is ejected and discharged, and the solvent level in the nozzle 10 is maintained at an appropriate level. The high-speed airflow containing the solvent injected in the standby pod 40 hits the porous buffer member 45. The buffer member (metal mesh in this example) 45 captures the solvent contained in the high-speed airflow while passing the airflow. The nitrogen gas that has passed through the buffer member 45 is exhausted through the exhaust port 44. At this time, the exhaust port 44 is strongly sucked and exhausted. Cushioning member 45
A part of the solvent trapped in the liquid is dropped and discharged from the drain port 43, and the other solvent is vaporized and exhausted from the exhaust port 44.

As described above, the standby pod 40 of this embodiment is
According to the configuration described above, the solvent discharged in the standby pod 40 is captured by the buffer member 45, so that mist of the solvent hardly occurs in the standby pod 40. Therefore, the mist of the solvent does not leak from the standby pod 40 and contaminate the substrate W.

When the pre-dispensing of the solvent is completed, the solvent spray nozzle 10 is immediately moved onto the substrate W. Then, while the substrate W is being rotated at a low speed, the supply of the solvent to the nozzle 10 is started and at the same time the nitrogen gas is supplied to the nozzle 1
The solvent is sprayed from 0 toward the substrate W. Since the liquid level of the solvent in the nozzle 10 is maintained constant by the pre-dispensing of the solvent, the droplet of the solvent does not come out of the nozzle 10 and the amount of the solvent to be jetted does not become insufficient, and the substrate W Solvent can be uniformly attached to the surface.

After the surface of the substrate W is wetted with the solvent, the solvent spray nozzle 10 is returned to the standby pod 40 to be in a standby state. On the other hand, the photoresist supply nozzle 25 is
And a predetermined amount of photoresist liquid is discharged onto the substrate W while the substrate W is rotated at a low speed. Subsequently, the substrate W is rotated at a high speed to form a photoresist film on the substrate W. Since the surface of the substrate W is uniformly wet with the solvent, a uniform film can be formed with a relatively small amount of the photoresist solution.

When the formation of the film on the substrate W is completed, the photoresist supply nozzle 25 is returned to the standby position.
The processed substrate W is carried out of the apparatus of the embodiment. afterwards,
A new substrate W is carried into the apparatus, and the same processing as described above is repeatedly performed.

<Second Embodiment> FIG. 3 is a sectional view of a standby pod used in a second embodiment of the present invention. The other configuration is the same as that of the first embodiment, and the description is omitted here. The feature of this embodiment is that the inside of the standby pod 40
The point is that the porous buffer member 46 disposed at a position for receiving the solvent sprayed from the solvent spray nozzle 10 inserted from the nozzle insertion port 42 is constituted by a cylindrical filter 46a. Although the material of the filter 46a is not particularly limited, for example, cloth, paper, or the like can be used in addition to a synthetic resin such as PTFE (polytetrafluoroethylene). The cylindrical filter 46a is attached and fixed to the ceiling surface of the outer container 41 by a holder 46b formed of a metal wire or the like. In the present embodiment, the filter is not provided on the bottom side because the solvent injected directly below the bottom is relatively small. However, as in the first embodiment shown in FIG. 2, the filter is also provided on the bottom side. It may be provided.

In this embodiment, as in the first embodiment,
The solvent injected in the standby pod 40 is captured by the filter 46a of the buffer member 46, and the high-speed airflow passes through the filter 46a and is exhausted from the exhaust port 44. Therefore, since the solvent injected from the solvent spray nozzle 10 does not directly hit the wall surface of the outer container 41, the standby pod 40
The mist of the solvent generated in the inside is small, and leakage of the mist out of the standby pod 40 can be suppressed.

<Third Embodiment> FIG. 4 is a sectional view of a standby pod used in a third embodiment of the present invention. The other configuration is the same as that of the first embodiment, and the description is omitted here. This embodiment is characterized in that a porous buffer member 47 for receiving the solvent sprayed from the solvent spray nozzle 10 inserted from the nozzle insertion port 42 is used as a plate-shaped filter 47a.
And a holder 47b formed of a metal wire or the like.
And is fixed substantially horizontally within the standby pod 40 via the. In the present embodiment, similarly to the first and second embodiments, the solvent sprayed from the solvent spray nozzle 10 is captured by the buffer member 47, and the airflow passing through the buffer member 47b is exhausted from the exhaust port 44. In addition, the mist of the solvent in the standby pod 40 can be suppressed. In the present embodiment, the buffer member 47 is constituted by the filter 47a, but may be constituted by a metal mesh as in the first embodiment.

The present invention is not limited to the above embodiments, but may be modified as follows. (1) In the embodiment, the substrate processing apparatus provided with the solvent spray nozzle 10 and the photoresist discharge nozzle 25 is taken as an example, but the present invention is also applied to the substrate processing apparatus provided with only the solvent spray nozzle 10. Can be applied.

(2) In the embodiment, the formation of a film of a photoresist solution is taken as an example, but the present invention can also be applied to the case of forming a film of an SOG solution or a polyimide resin. Further, the present invention can be applied not only as a pre-treatment for forming a film but also to various treatments that require a solvent to be uniformly adhered to a substrate.

(3) The cushioning member of the present invention can be formed of various materials other than the materials described in the above embodiment. For example, a metal plate in which many small holes are punched can be used as a buffer member.

(4) In the embodiment, the case where the pre-dispensing of the solvent ejects and discharges the solvent L ′ hanging down in the solvent flow path 12a in the nozzle 10 has been described as an example.
The present invention can be applied to the case where the waiting time of the nosle 10 is long. Specifically, in response to the fact that the liquid level of the solvent L ′ in the nozzle 10 retreats in the solvent flow path 12a and retreats from a portion that intersects with the gas flow path 12b, the pre-dispensing of the solvent in the standby pod 40 is performed. Is performed as follows. That is, only the solvent is supplied to the solvent spray nozzle 10. By doing so, as shown in FIG. 5 (c), the liquid level of the solvent L ′ in the solvent flow path 12a in the nozzle 10 is lowered and located below a portion that intersects the gas flow path 12b. Next, the gas flow path 12
When nitrogen gas is supplied at a high speed from b, the solvent L ′ is ejected and discharged, and the solvent level in the nozzle 10 is maintained at an appropriate level. In the standby pod 40, the buffer member 45 captures the solvent and allows the airflow to pass, as in the above embodiment.
In this case, it is not necessary to perform the pre-dispense every time the solvent spraying process is performed, and one pre-dispense may be performed before the continuous solvent spraying process.

[0036]

As apparent from the above description, the present invention has the following effects. According to the first aspect of the present invention, since the solvent ejected in the standby pod is received by the porous buffer member and the solvent is captured by the buffer member, mist of the solvent is generated in the standby pod. Can be suppressed. Therefore, according to the present invention, the mist of the solvent does not leak to the outside from the standby pod, so that the substrate is not contaminated.

According to the second and third aspects of the present invention, the corrosion-resistant metal mesh (claim 2) or the filter (claim 3) provided in the standby pod is supplied from the solvent spray nozzle. Since the carried-out solvent is captured, the mist of the solvent does not leak to the outside from the standby pod.

According to the fourth aspect of the present invention, since the distribution of the solvent adhering to the substrate is uniform, a coating film can be uniformly formed on the substrate with a relatively small amount of the coating liquid. In addition, the substrate is not contaminated by the mist of the solvent leaked from the standby pot.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a first embodiment of a substrate processing apparatus according to the present invention.

FIG. 2 is a sectional view of a standby pod according to the first embodiment.

FIG. 3 is a sectional view of a standby pod according to a second embodiment.

FIG. 4 is a sectional view of a standby pod according to a third embodiment.

FIG. 5 is a cross-sectional view of a nozzle for explaining the problem of the present invention.

FIG. 6 is a sectional view of a standby pod for explaining the problem of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Nozzle for solvent spray 25 ... Nozzle for discharge of photoresist 40 ... Stand-by pod 42 ... Nozzle insertion port 44 ... Exhaust port 45, 46, 47 ... Buffer member

Claims (4)

[Claims] 1. A substrate configured to insert a solvent spray nozzle into a standby pod and discharge a solvent remaining in the solvent spray nozzle in advance before spraying a solvent onto the substrate and performing a required process. In the processing apparatus, the standby pod includes a nozzle insertion port for inserting a solvent spray nozzle in the standby pod, and a solvent spray nozzle inserted in the nozzle insertion port in the standby pod. A porous buffer member is provided at a position for receiving the solvent sprayed from the substrate. 2. The substrate processing apparatus according to claim 1, wherein the buffer member is formed of a mesh made of a corrosion-resistant metal. 3. The substrate processing apparatus according to claim 1, wherein the buffer member is formed of a porous filter. 4. The substrate processing apparatus according to claim 1, further comprising: a rotation holding mechanism for rotating and holding the substrate; and a coating liquid supply mechanism for supplying a coating liquid to the substrate. Substrate processing equipment.