JP2002336675A - Apparatus and method for treating under high pressure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for treating a substrate under high pressure, in which the substrate can be treated by using a pure processing fluid so that the atmospheric component intruded into a treating tank when the substrate is placed is not made to flow in a fluid producing/recovering system. SOLUTION: Valves V1, V2, V3, V4 and V6 are closed and only a valve V5 is opened when the door of a substrate cleaning tank 5 is opened for placing the substrate so that gaseous carbon dioxide is supplied to the tank 5 and the tank 5 is purged for preventing the atmospheric component from intruding into the tank 5. Next, the door of the tank 5 is closed and the valve V6 is opened at the same time to form a venting line of the tank 5 so that the gas existing in the tank 5 and its surrounding pipes is pushed out to the atmosphere by the supplied gaseous carbon dioxide and the tank 5 is purged so that the atmospheric component to intrude into the tank 5 and its surrounding pipes by some rare accident does not stay behind. Then, the substrate is cleaned by using supercritical carbon dioxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-pressure processing apparatus and method using a processing fluid in a high-pressure state, and more particularly to an FP such as a semiconductor substrate or a glass substrate for a liquid crystal display device.
A high-pressure processing apparatus and method for supplying a high-pressure fluid to a D (Flat Panel Display) substrate, a photomask glass substrate, an optical disk substrate, and the like (hereinafter, simply referred to as a “substrate”). The present invention relates to a high-pressure processing apparatus and method for performing an object removing process and the like. In addition, the present invention relates to a high-pressure processing apparatus and method used for a drying process for removing moisture adhering to a substrate surface and a developing process for removing unnecessary portions existing on the substrate surface.

[0002]

2. Description of the Related Art In recent years, with the flow of defluorocarbon in cleaning a substrate on which electronic parts and the like are formed, a low-viscosity high-pressure processing fluid such as supercritical carbon dioxide is used as a stripping liquid or a rinsing liquid. It has been noted.

In addition, due to the recent shrinking of semiconductor devices (shrinking), device design rules (technology nodes) have been further miniaturized, and the momentum has been further accelerated. In such a semiconductor device, a very fine groove (trench) or hole (hole) is structurally very small.
Cleaning is required. The former is a capacitor (capacitance portion of a capacitor) and horizontal wiring (planar wiring), and the latter is vertical wiring (three-dimensional wiring, connection between horizontal wiring and horizontal wiring, connection to gate electrode of transistor), and the like. .

In such a fine structure, the ratio of the width to the depth, that is, the so-called aspect ratio (aspect ratio) has become extremely large, and a narrow groove having a narrow width and a deep hole having a small diameter have been formed. I have. Some of them have a width or diameter of submicron and an aspect ratio of more than 10. After such a microstructure is manufactured on a semiconductor substrate by dry etching or the like, not only the upper flat portion but also the sidewalls and bottoms of the grooves and holes, the resist debris, the resist altered by dry etching, and the metal at the bottom are formed. And contamination of the resist compound, oxidized metal and the like remain.

Conventionally, these contaminants have been cleaned with a solution-based chemical. However, with such a fine structure, the penetration of the chemical solution and the replacement with pure water are not smooth, and cleaning failures are occurring. In addition, a material having a low dielectric constant (a so-called Low-k) is used in order to prevent the etched insulator from delaying an electric signal due to wiring.
) Must be used, and there is a problem that the chemical solution deteriorates the low dielectric constant, which is its characteristic. In addition, when the metal for wiring is exposed, there is a restriction that a chemical solution for dissolving the metal cannot be used.

[0006] Supercritical fluids have attracted attention for cleaning such fine structures of semiconductor devices because of their properties. Here, the supercritical fluid is, as shown in FIG.
It refers to the state of a substance obtained at a temperature equal to or higher than c and equal to or higher than the critical temperature Tc (shaded portion in the figure). Since this supercritical fluid has intermediate properties between liquid and gas, it can be said that it is suitable for precise cleaning. In other words, supercritical fluids have a density close to that of liquids and have high solubility, so they are effective for cleaning organic components.Because they have excellent diffusivity like gas, they can be uniformly cleaned in a short time, Because of its low viscosity, it is suitable for cleaning fine parts.

As the substance to be converted into the supercritical fluid, carbon dioxide, water, nitrous oxide, ammonia, ethanol and the like are used. Carbon dioxide is often used because it has a critical pressure Pc of 7.4 MPa and a critical temperature Tc of about 31 ° C., and can obtain a supercritical state relatively easily and is nontoxic.

The supercritical fluid of carbon dioxide itself is inactive, but since the carbon dioxide fluid has a dissolving power on the order of hexane, it is possible to easily remove moisture, oils and fats from the substrate surface. Further, for example, when amines and ammonium fluoride used for cleaning contamination of the semiconductor substrate are mixed,
It becomes a multicomponent supercritical fluid in a certain appropriate concentration range, and can easily penetrate a fine device structure to remove the above-mentioned contamination. Further, amines, ammonium fluoride, and the like contaminated with the contamination can be easily removed from the fine device structure.

In addition, the supercritical fluid does not remain even if it penetrates into an insulator having a low dielectric constant, such as a solution-based chemical, so that its characteristics are not changed. Therefore, it is very suitable for cleaning the fine structure of a semiconductor device.

[0010] As an apparatus for cleaning a substrate using the supercritical fluid, a configuration shown in FIG. 4 is conceivable. FIG.
The high-pressure processing apparatus shown in FIG. 1 includes a cylinder 11 filled with liquid carbon dioxide, a condenser 12, a booster 13, and a heater 1
4, substrate cleaning tank 15, decompressor 17, and separation and recovery tank 1
8 and valves V1 and V2.

Hereinafter, the cleaning operation of the high-pressure processing apparatus having the above configuration will be briefly described. First, the substrate to be cleaned is
It is set in the substrate cleaning tank 15 and hermetically closed. When the substrate is set, the following cleaning process is started. First, the liquefied carbon dioxide in the cylinder 11 is supplied to the condenser 12 and stored as a liquid. The liquefied carbon dioxide is boosted to a pressure equal to or higher than the critical pressure Pc in the booster 13, is further heated to a temperature equal to or higher than the critical temperature Tc in the heater 14, becomes supercritical carbon dioxide, and is sent to the substrate cleaning tank 15.
In the substrate cleaning tank 15, cleaning is performed by bringing supercritical carbon dioxide into contact with the substrate.

The supercritical carbon dioxide mixed with the contaminants after cleaning the substrate (organic substances, inorganic substances, metals, particles, water, etc. mixed into the supercritical carbon dioxide from the substrate by the cleaning) is subjected to a final decompression in the decompressor 17. After being made and vaporized, it is separated in a separation and recovery tank 18 into gaseous carbon dioxide gas and pollutants. The separated pollutants are discharged, and the carbon dioxide gas is recovered and reused in the condenser 12. The above cleaning process was repeated for a predetermined time,
Substrate cleaning is completed.

[0013]

However, in the configuration of the above-mentioned conventional high-pressure processing apparatus, the substrate is cleaned in the substrate cleaning tank 1.
At the time of installation in the inside, the air enters the tank from the opening of the door. For this reason, when recovering / reusing the supercritical fluid after the cleaning process, the atmospheric component mixed in the substrate cleaning tank 15 flows into the supercritical fluid generation / recovery system, and the purity of the supercritical fluid used for cleaning is Will be reduced.

When such a high-pressure processing apparatus is used for cleaning a semiconductor substrate, the substrate cleaning tank 15 is installed in a clean room. The air in this clean room contains S
This is because, in addition to Ox and NOx, various contaminants such as siloxane, boron, and organic vapor are contained.

This decrease in purity causes a system instability due to a change in the condensation temperature of the collected and reused carbon dioxide gas, and deteriorates the performance of the substrate cleaning using supercritical carbon dioxide. Become.

Such a problem is not limited to the cleaning method using a supercritical fluid, and a substrate is developed and cleaned in a closed processing tank using a subcritical fluid or a high-pressure gas such as ammonia.
The same applies to high-pressure treatment such as drying.

Here, the subcritical fluid generally refers to a liquid in a high pressure state in a region just before the critical point in FIG. Fluids in this region may be distinguished from supercritical fluids, but since physical properties such as density change continuously, there is no physical boundary and they are used as subcritical fluids In some cases. Those existing in the subcritical or supercritical region near the critical point in a broad sense are also referred to as high-density liquefied gas.

That is, in such a high-pressure processing apparatus using a high-pressure fluid, there is room for improvement in preventing deterioration of the processing performance when the high-pressure processing fluid after processing is recovered / reused.

Therefore, an object of the present invention is to perform substrate processing using a pure high-pressure fluid without causing atmospheric components mixed in the processing tank at the time of substrate installation to flow into the high-pressure fluid generation / recovery system. To provide a high-pressure processing apparatus and method.

[0020]

Means for Solving the Problems and Effects of the Invention In order to achieve the above object, the present invention has the following features. A first invention is a high-pressure processing apparatus for performing a predetermined process on a substrate using a high-pressure fluid, the high-pressure fluid supply unit supplying a predetermined process fluid in a high-pressure state, and a high-pressure fluid supply unit supplying the high-pressure fluid supply unit. A high-pressure fluid, a high-pressure fluid collecting unit that collects and reuses the high-pressure fluid after the substrate processing in the substrate processing unit, and a high-pressure fluid. A supply processing unit that supplies the same atmosphere replacement fluid into the processing tank and a discharge processing unit that discharges gas in the processing tank are provided. After the substrate is installed and sealed in the processing tank, high-pressure fluid is supplied. Until the supply of the atmosphere replacement fluid, the supply processing unit supplies the atmosphere replacement fluid into the processing tank, and the discharge processing unit discharges the gas in the processing tank pushed out by the supply of the atmosphere replacement fluid.

As described above, according to the first aspect, a vent line is formed in a processing tank in which a substrate is installed, and an atmosphere replacement fluid having the same component as the high-pressure fluid used in the processing is supplied to the processing tank. Then, the air component mixed at the time of setting the substrate is pushed out by the fluid. Thereby, the atmospheric component mixed in the processing tank does not flow into the high-pressure fluid recovery unit.

A second invention is an invention according to the first invention, wherein the supply processing section supplies the processing fluid before being brought into a high pressure state as an atmosphere replacement fluid.

As described above, according to the second aspect of the present invention, the processing fluid before the high-pressure state is used as the atmosphere replacement fluid. As a result, an atmosphere replacement fluid having the same components can be easily obtained.

According to a third aspect of the present invention, there is provided a high-pressure processing apparatus for performing a predetermined process on a substrate using a supercritical fluid, comprising: a supercritical fluid supply unit for supplying a predetermined supercritical fluid; A substrate processing unit that processes the supplied supercritical fluid by contacting it with a substrate installed in a processing tank, and a supercritical fluid recovery that recovers and reuses the supercritical fluid after substrate processing in the substrate processing unit Section, a supply processing section for supplying an atmosphere replacement fluid of the same component as the supercritical fluid into the processing tank, and a discharge processing section for discharging gas in the processing tank. Until the supercritical fluid is supplied after being supplied, the supply processing unit supplies the atmosphere replacement fluid into the processing tank,
The discharge processing unit discharges the gas in the processing tank pushed out by the supply of the atmosphere replacement fluid.

As described above, according to the third aspect, a vent line is formed in a processing tank in which a substrate is installed, and a fluid having the same component as a supercritical fluid used for processing is supplied to the processing tank. Atmospheric components mixed during substrate installation are pushed out by this fluid. Accordingly, the atmospheric component mixed in the processing tank does not flow into the supercritical fluid recovery unit, so that the substrate processing can be performed using a pure supercritical fluid without lowering the purity.

A fourth invention is an invention according to the third invention, wherein the supply processing section supplies the processing fluid before being brought into the supercritical state as an atmosphere replacement fluid.

As described above, according to the fourth aspect, the processing fluid before being brought into the supercritical state is used as the atmosphere replacement fluid. As a result, an atmosphere replacement fluid having the same components can be easily obtained.

A fifth invention is an invention according to the third and fourth inventions, wherein the supply processing section supplies the atmosphere replacement fluid to the processing tank until the substrate is set in the processing tank and hermetically sealed. It is characterized by supplying to.

As described above, according to the fifth aspect, a fluid having the same component as the supercritical fluid used for the processing is supplied to the processing tank in a state where the door of the processing tank is opened. This allows
It is possible to prevent in advance the mixing of atmospheric components into the cleaning tank in the open-to-atmosphere state.

A sixth aspect of the invention is an invention according to the third to fifth aspects, wherein the substrate processing section processes the substrate by circulating a supercritical fluid.

As described above, according to the sixth aspect, the supercritical fluid used for processing the substrate can be used efficiently.

A seventh aspect of the present invention is the invention according to the third to sixth aspects, wherein the supply processing section supplies a pure supercritical fluid in which no auxiliary agent is mixed.

As described above, according to the seventh aspect, the supply processing section supplies a pure fluid. Therefore, the auxiliary agent is not consumed more than necessary.

An eighth invention is a high-pressure processing method for performing a predetermined process on a substrate using a supercritical fluid, wherein the substrate is placed in a processing tank for processing the substrate, sealed, and then subjected to a supercritical process. A step of supplying an atmosphere replacement fluid having the same component as the fluid into the processing tank; a step of discharging gas in the processing tank pushed out by the supplied atmosphere replacement fluid; and a step of supplying a predetermined supercritical fluid. The method includes a step of processing a substrate installed in a processing bath using the supplied supercritical fluid, and a step of collecting and reusing the supercritical fluid after the substrate processing.

As described above, according to the eighth aspect, after the substrate is installed and sealed, a fluid having the same component as the supercritical fluid used for processing is supplied to the processing tank, and gas in the processing tank is released. Extrude and eject. As a result, it is possible to eliminate the atmospheric components mixed into the processing tank at the time of substrate installation, so that it is possible to prevent the atmospheric components from flowing into the path for collecting the supercritical fluid, and to purify the pure supercritical fluid without reducing the purity. Can be used for substrate processing.

A ninth invention is the invention according to the eighth invention, wherein the atmosphere replacement fluid is a processing fluid before being brought into a supercritical state.

As described above, according to the ninth aspect, the processing fluid before being brought into the supercritical state is used as the atmosphere replacement fluid. As a result, an atmosphere replacement fluid having the same components can be easily obtained.

A tenth invention is according to the eighth and ninth inventions, and comprises a step of supplying an atmosphere replacement fluid into the processing tank until the substrate is placed in the processing tank and sealed. Further prepare.

As described above, according to the tenth aspect, even when the door of the processing tank is open, a fluid having the same component as the supercritical fluid used for processing is supplied to the processing tank. Thereby, the contamination of the atmospheric components into the processing tank in the open-to-atmosphere state can be prevented in advance.

[0040]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. A typical example of the treatment in the high-pressure treatment apparatus of the present invention is a cleaning treatment in which a contaminant is separated and removed from an object to which the contaminant is attached, such as a semiconductor substrate to which a resist is attached. The substrate as the object to be processed is not limited to a semiconductor substrate, but may be a substrate in which a discontinuous or continuous layer of a heterogeneous substance is formed or remains on various substrates such as metal, plastic, and ceramic. included.

FIG. 1 is a block diagram showing a configuration of a high-pressure processing apparatus according to one embodiment of the present invention. In FIG.
The high-pressure processing apparatus according to the present embodiment includes a cylinder 1, a condenser 2, a booster 3, a heater 4, a substrate cleaning tank 5, a decompressor 7, a separation and recovery tank 8, valves V1 to V6. , A circulation pump 6 and a vaporizer 21.

First, each configuration of the high-pressure processing apparatus of the present embodiment will be described. The cylinder 1 is filled with liquefied carbon dioxide used for cleaning the substrate. The condenser 2 cools and liquefies gaseous carbon dioxide supplied from the separation and recovery tank 8. The booster 3 boosts the liquefied carbon dioxide liquefied in the condenser 2 to a predetermined pressure equal to or higher than the critical pressure Pc. The heater 4 heats the liquefied carbon dioxide pressurized by the booster 3 to a predetermined temperature equal to or higher than the critical temperature Tc. As a result, the liquefied carbon dioxide changes into a supercritical fluid (see FIG. 3).
See). The supercritical carbon dioxide corresponds to one of the high-pressure processing fluids applicable to the present invention.

In the substrate cleaning tank 5 as a processing tank, the substrate is cleaned using the generated supercritical carbon dioxide. The decompressor 7 vaporizes the supercritical carbon dioxide that has been subjected to the cleaning process in the substrate cleaning tank 5 by decompression. In the separation / recovery tank 8, the carbon dioxide gas vaporized by the pressure reducer 7 and the contaminants are separated, and the carbon dioxide gas is supplied to the condenser 2 again.

The valves V1 and V2 are used to separate the supercritical fluid generation / recovery system from the cleaning treatment circulation system. The valve V1 is provided on a pipe connecting the secondary side of the booster 3 and the primary side of the heater 4. The valve V2 is provided on a pipe connecting the secondary side of the substrate cleaning tank 5 and the primary side of the pressure reducer 7.

The valves V3 and V4 are valves used to form a cleaning circulation system. Valve V3 is
It is provided on a pipe connecting the discharge port of the circulation pump 6 and the primary side of the heater 4. The valve V4 is provided on a pipe connecting the secondary side of the substrate cleaning tank 5 and the suction port of the circulation pump 6.

The valves V5 and V6 are used for purging (replacement of the atmosphere) the inside of the substrate cleaning tank 5. The valve V5 is provided on a pipe connecting the cylinder 1 and the primary side of the substrate cleaning tank 5 via the vaporizer 21. The valve V6 is provided on a pipe that opens the secondary side of the substrate cleaning tank 5 to the atmosphere.

Here, the piping system from the cylinder 1 to the substrate cleaning tank 5 via the valve V1 corresponds to the supply section of the high pressure fluid of the present invention, and the piping from the cylinder 1 to the substrate cleaning tank 5 via the valve V5. The system corresponds to the supply processing unit, and the piping system opened from the substrate cleaning tank 5 to the atmosphere via the valve V6 corresponds to the discharge processing unit. The substrate cleaning tank 5 constitutes a substrate processing section, and the condenser 2 is connected to the substrate cleaning tank 5 via the valve V2.
The piping system leading to constitutes a recovery unit.

Next, the high-pressure processing performed by the high-pressure processing apparatus according to this embodiment according to this embodiment, that is, the substrate cleaning operation will be described. In the present embodiment, a case where carbon dioxide is used as the processing fluid will be described. However, other substances that can change to a supercritical fluid state such as nitrous oxide, alcohol, ethanol, and water may be used. Further, the substrate cleaning method used in the substrate cleaning tank of the present embodiment may be either a batch method for simultaneously cleaning a plurality of substrates or a single-wafer method.

First, the substrate to be cleaned is placed in the substrate cleaning tank 5.
It is installed in. When the substrate is installed, the valves V1, V
2, V3, V4 and V6 are closed, and only the valve V5 is opened (step S21).

First, carbon dioxide used as a processing fluid is stored in the cylinder 1 as a liquid fluid at a pressure of 5 to 6 MPa. The liquefied carbon dioxide is taken out of the cylinder 1 by a pump (not shown) and is vaporized. It is sent to and vaporized. By opening the valve V5, the vaporized carbon dioxide gas is supplied to the substrate cleaning tank 5 as an atmosphere replacement (step S22).

As described above, in the present invention, first, in the state where the door of the substrate cleaning tank 5 is open, the processing fluid having the same component as the supercritical carbon dioxide used for cleaning, that is, the carbon dioxide gas is supplied without pressure increase or heating. By supplying as an atmosphere replacement fluid, mixing of atmospheric components into the substrate cleaning tank 5 is prevented (purge in an open tank).

Next, the substrate is set and the door of the substrate cleaning tank 5 is closed, and at the same time, the valve V6 is opened (step S23). By opening this valve V6,
A route (vent line) of cylinder 1 → substrate cleaning tank 5 → open to atmosphere is formed, and carbon dioxide gas is continuously supplied (step S24).

As described above, in the present invention, the gas in the substrate cleaning tank 5 and the piping is pushed out to the atmosphere by continuously supplying the carbon dioxide gas with the door of the substrate cleaning tank 5 closed. (That is, the gas in the substrate cleaning tank 5 and the pipe is replaced with carbon dioxide gas), and the atmosphere is replaced so that the mixed atmospheric components do not remain (purge in the closed tank).

When the mixed atmospheric components are pushed out and the inside of the substrate cleaning tank 5 and the piping are filled with only carbon dioxide gas, the valves V5 and V6 are closed, and the valves V1 and V2 are opened to open the supercritical fluid. A generation / recovery system is formed (Step S25). When the supercritical fluid generation / recovery system is formed, liquefied carbon dioxide is supplied from the cylinder 1 to the condenser 2.

The liquefied carbon dioxide stored as a liquid in the condenser 2 is pressurized to a pressure higher than the critical pressure Pc in the booster 3 and further heated to a predetermined temperature higher than the critical temperature Tc in the heater 4 to be supercritical. It becomes a fluid and is sequentially sent to the substrate cleaning tank 5 (step S25).

Here, the predetermined pressure and temperature can be freely set based on the type of the substrate to be cleaned and the desired cleaning performance. In the substrate cleaning tank 5, the substrate is cleaned with the supercritical carbon dioxide in the high pressure state.

When the supercritical fluid generation / recovery system (from the secondary side of the heater 4 to the primary side of the pressure reducer 7) is filled with supercritical carbon dioxide, the valves V1 and V2 are closed, and the valves V1 and V2 are closed.
3, opening of V4 and turning on the operation of the circulation pump 6 circulates the supercritical carbon dioxide in the cleaning circulation system for a predetermined time to clean the substrate (step S2).
6).

The circulation cleaning of the substrate is performed in order to suppress the consumption of the supercritical carbon dioxide and to make the substrate more effective. As a result, a reduction in running cost is achieved, and more economical processing becomes possible. Depending on the substrate to be cleaned, cleaning may be performed by mixing an auxiliary agent (chemical solution such as amine or ammonium fluoride for removing the resist) with supercritical carbon dioxide on a pipe just before the substrate cleaning tank 5. There is,
In the present invention, each tank is purged with pure carbon dioxide gas containing no auxiliary agent.

When the cleaning of the substrate is completed, the valve V2 is opened to recover / recycle the supercritical carbon dioxide (step S27). The supercritical carbon dioxide in a high-pressure state mixed with the contaminants by the substrate washing is decompressed and vaporized in the decompressor 7, and then separated into gaseous carbon dioxide and the contaminants in the separation and recovery tank 8. The separated pollutants are discharged, and the carbon dioxide gas is recovered and reused in the condenser 2. For example, the decompressor 7 maintains the supercritical carbon dioxide at about 80 ° C. or higher and increases the pressure from 15 MPa to 6 MPa.
It is converted into gaseous carbon dioxide by reducing the pressure to MPa.

When the recovery of the supercritical carbon dioxide is completed, the valves 2, V3 and V4 are closed, the valves V5 and V6 are opened, and the carbon dioxide gas is supplied again into the substrate cleaning tank 5 (sealed tank). (Internal purging) (step S28). The removal of the substrate set in the substrate cleaning tank 5 is performed in a state where the valve V6 is closed and the entry of atmospheric components into the substrate cleaning tank 5 is prevented (purging in the open tank) (step S29). ).

Thereafter, when the substrate is taken out of the substrate cleaning tank 5 and the door is closed, the valve V5 is closed and the process ends (step S30). If another substrate is to be continuously cleaned, the process may return to step S23 after step S29 is completed, and the above-described processing may be repeated.

As described above, the high-pressure processing apparatus and method according to one embodiment of the present invention provide the substrate cleaning tank 5 with the same component as the supercritical fluid used for cleaning when the substrate is installed. Preventing atmospheric components from being mixed into the substrate cleaning tank 5 in the open-to-atmosphere state (purging in the open tank). further,
By forming a vent line in the sealed substrate cleaning tank 5 and supplying a fluid to the substrate cleaning tank 5, the contaminated atmospheric components are pushed out by this atmosphere replacement fluid (purge in the sealed tank). This prevents the atmospheric components mixed in the substrate cleaning tank 5 from flowing into the supercritical fluid generation / recovery system at the time of substrate installation, so that the substrate is cleaned using a pure supercritical fluid without lowering the purity. be able to.

It should be noted that the present invention is not limited to the above-described embodiments and modifications, but can be implemented in other forms as described below.

(1) In the above-described embodiment, a process for preventing atmospheric components from being mixed into the substrate cleaning tank 5 (purging in the open tank) by supplying carbon dioxide gas while the door of the substrate cleaning tank 5 is open. ) First (steps S21, S
22). However, by supplying carbon dioxide gas in a state where the door of the substrate cleaning tank 5 is closed without performing this processing, the gas in the substrate cleaning tank 5 and the piping is pushed out to the atmosphere, and the mixed atmospheric components May be performed only to prevent the residual (purging in the closed tank). Even in this case, the above-described effects can be obtained.

(2) In the above embodiment, the gas in the substrate cleaning tank 5 and the piping is pushed out to the atmosphere by purging the inside of the tank, but the valves V3 and V4 and the circulation pump 6 are used. The gas in the piping may be pushed out to the atmosphere via the cleaning circulation circuit constituted by the above and the valve V6.

(3) In the above embodiment, the case where the dedicated valve V6 for pushing out the gas in the substrate cleaning tank 5 and the pipe into the atmosphere is provided, but the path through which the gas can be discharged is separately provided. If it is present (for example, the discharge path of the separation and recovery tank 8), it is not necessary to separately provide a discharge path by the valve V6.

(4) In the above embodiment, in order to effectively use the supercritical carbon dioxide, a cleaning treatment circulation system is constituted by using the valves V3 and V4 and the circulation pump 6, and the supercritical carbon dioxide is supplied to a predetermined amount. The substrate is cleaned by circulating only for a period. However, the substrate cleaning may be performed only by the supercritical fluid generation / recovery system without forming a cleaning processing circulation system.

(5) Further, the installation location of each of the valves V1 to V6 is not limited to the position described in the above embodiment, and may be provided at another position as long as the above-described vent line can be formed.

(6) In the above embodiment, the decompressor 7 is disposed downstream of the substrate cleaning tank 5 so that the supercritical fluid is vaporized and then sent to the separation and recovery tank 8.
After the pressure in the separation and recovery tank 8 is reduced, gas-liquid separation may be performed.

(7) The above high-pressure processing apparatus has been described with respect to substrate cleaning. However, the present invention is not limited to this. Drying and developing for removing unnecessary substances from the substrate using a high-pressure fluid and a chemical solution other than the high-pressure fluid. All treatments and the like can be the object of the high-pressure treatment of the present invention. That is, the substrate after the rinsing cleaning (washing with water) is carried in and installed in the substrate cleaning tank 5. In the substrate cleaning tank 5, the moisture adhering to the substrate is dissolved and removed in the supercritical or subcritical high-pressure processing fluid. After this,
The processing fluid is collected and reused as in the above embodiment.

In the substrate development, the silicon wafer on which the resist pattern has been formed is carried into the substrate cleaning tank 5 and installed. In the substrate cleaning tank 5, the resist pattern on the substrate is developed with a supercritical or subcritical high-pressure processing fluid.

(8) The processing operation of the substrate is not limited to the case where the developing process, the cleaning process, and the drying process are independently performed, and the drying process is continuously performed on the substrate after the developing process. May be implemented. Further, the cleaning process may be performed on the substrate after the drying process.

(9) In the above embodiment, the processing fluid is supplied to the substrate cleaning tank 5 as a supercritical fluid.
The predetermined high pressure state supplied to the substrate cleaning tank 5 is 1 MPa
It is a fluid with the above pressure. Preferably, it is a fluid having properties of high density, high solubility, low viscosity, and high diffusivity.
The reason for using a high-pressure fluid is that it has a high diffusion coefficient and can dissolve dissolved contaminants in a medium. As a result, it is possible to further penetrate even fine pattern portions.
The high-pressure fluid also has a density close to that of a liquid, and can contain a much larger amount of additives (chemicals) than a gas.

Further preferred is a fluid in a supercritical or subcritical state. It is preferable to use a subcritical (high-pressure fluid) or a supercritical fluid of 5 to 30 MPa for the washing and the rinsing step or the drying / developing step after the washing, and more preferably to perform these treatments at 7.1 to 20 MPa. That is.

In addition, it is possible to make various design changes within the technical scope described in the claims.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a high-pressure processing apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a procedure of a high-pressure processing method according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a supercritical fluid.

FIG. 4 is a block diagram showing an example of the configuration of a conventional apparatus for cleaning a substrate using a supercritical fluid.

[Explanation of symbols]

 1,11 ... cylinder 2,12 ... condenser 3,13 ... booster 4,14 ... heater 5,15 ... substrate washing tank 6 ... circulation pump 7,17 ... decompressor 8,18 ... separation and recovery tank 21 ... Vaporizer V1-V6 ... Valve

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02F 1/1333 500 G02F 1/1333 500 H01L 21/304 641 H01L 21/304 641 (72) Inventor Yusuke Muraoka 1-4-1 Tenjin Kitamachi, Horikawa-dori Teranouchi, Kamigyo-ku, Kyoto Dai-Nippon Screen Manufacturing Co., Ltd. (72) Inventor: Kimitomo Saito 4-chome Tenjin Kita-machi, Horikawa-dori Terauchi, Kamigyo-ku, Kyoto No. 1 Dainippon Screen Manufacturing Co., Ltd. (72) Inventor Ryuji Kitamon 4-chome Tenjin Kitamachi 1-chome, Horikawa-dori Teranouchi, Kamigyo-ku, Kyoto 1 Dainippon Screen Manufacturing Co., Ltd. (72) Inventor Yoichi Inoue 2-3-1 Shinhama, Arai-machi, Takasago City, Hyogo Prefecture Inside Kobe Steel, Ltd. Takasago Works (72) Inventor Yoshihiko Sakashita 2-3-1, Shinhama, Arai-machi, Takasago City, Kobe Prefecture Inside Kobe Steel, Ltd. Takasago Works (72) Inventor Katsumitsu Watanabe 2-3-1, Shinama, Araimachi, Takasago City, Hyogo Prefecture, Kobe Steel Works, Takasago Works (72 ) Inventor Masahiro Yamagata 2-3-1 Shinhama, Arai-machi, Takasago-shi, Hyogo F-term in Kobe Steel, Ltd. Takasago Works (reference) 2H088 FA21 HA01 2H090 JC19 3B116 AA01 AB02 BB02 BB72 BB88 BB90 CD11 CD22

Claims (10)

[Claims] 1. A high-pressure processing apparatus for performing a predetermined process on a substrate using a high-pressure fluid, comprising: a high-pressure fluid supply unit configured to supply a predetermined process fluid in a high-pressure state; A substrate processing unit that processes the high-pressure fluid by contacting the substrate installed in the processing tank; a high-pressure fluid recovery unit that recovers and reuses the high-pressure fluid after the substrate processing in the substrate processing unit; A supply processing unit that supplies an atmosphere replacement fluid having the same component as the high-pressure fluid into the processing tank; and a discharge processing unit that discharges gas in the processing tank. A substrate is installed and sealed in the processing tank. The supply processing unit supplies the atmosphere replacement fluid into the processing tank until the high-pressure fluid is supplied, and the gas in the processing tank is pushed out by the discharge processing unit by the supply of the atmosphere replacement fluid. Discharge A high-pressure processing device, characterized in that: 2. The high-pressure processing apparatus according to claim 1, wherein the supply processing unit supplies the processing fluid before being brought into a high-pressure state as the atmosphere replacement fluid. 3. A high-pressure processing apparatus for performing a predetermined process on a substrate using a supercritical fluid, comprising: a supercritical fluid supply unit for supplying a predetermined supercritical fluid; A substrate processing unit for processing the supercritical fluid by contacting the substrate installed in the processing tank; and a supercritical fluid recovery unit for recovering and reusing the supercritical fluid after the substrate processing in the substrate processing unit. A supply processing unit that supplies an atmosphere replacement fluid having the same component as the supercritical fluid into the processing tank; and a discharge processing unit that discharges gas in the processing tank. Until the supercritical fluid is supplied from being installed and sealed, the supply processing unit supplies the atmosphere replacement fluid into the processing tank, and the discharge processing unit is extruded by the supply of the atmosphere replacement fluid. Exhaust gas in the processing tank A high-pressure processing device, which is provided. 4. The high-pressure processing apparatus according to claim 3, wherein the supply processing unit supplies the processing fluid before being brought into a supercritical state as the atmosphere replacement fluid. 5. The supply processing section supplies the atmosphere replacement fluid to the processing tank until a substrate is placed in the processing tank and sealed.
Or the high-pressure processing apparatus according to 4. 6. The substrate processing unit according to claim 3, wherein the substrate processing unit processes the substrate by circulating the supercritical fluid.
The high-pressure processing apparatus according to any one of claims 1 to 5. 7. The high-pressure processing apparatus according to claim 3, wherein the supply processing unit supplies a pure supercritical fluid in which no auxiliary agent is mixed. 8. A high-pressure processing method for performing a predetermined process on a substrate by using a supercritical fluid, wherein the substrate is placed in a processing tank for processing the substrate and sealed, and then the same as the supercritical fluid. Supplying an atmosphere replacement fluid of a component into the processing tank; discharging gas in the processing tank pushed out by the supplied atmosphere replacement fluid; supplying a predetermined supercritical fluid; A high-pressure processing method comprising: a step of processing a substrate installed in the processing bath using the supercritical fluid that has been processed; and a step of collecting and reusing the supercritical fluid after the substrate processing. 9. The high-pressure processing method according to claim 8, wherein the atmosphere replacement fluid is a processing fluid before being brought into a supercritical state. 10. The high-pressure processing method according to claim 8, further comprising a step of supplying the atmosphere replacement fluid into the processing tank until a substrate is placed in the processing tank and sealed.