JP2000180055A - Substrate drying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To introduce a drying fluid in sufficient quantities without using a carrier gas by feeding only a drying fluid into a drying chamber, which stores a substrate being an object to be dried and can be airtightly closed, through a drying fluid guide pipe, and forcibly exhausting a gas in the drying chamber. SOLUTION: After a plurality of substrates 4 stored in a drying tank 1 are cleaned by feeding a cleaning liquid into the tank 1, the tank 1 is airtightly closed and a valve 3b is opened to actuate a vacuum pump 3, thereby exhausting a gas present in a space of the tank 1 to create a vacuum, causing a drying fluid to be introduced into the space. If the cleaning liquid in the tank 1 is discharged through a cleaning liquid discharge pipe 1a, a vacuum is produced in the tank 1, whereby a drying fluid in such a quantity that corresponds to the quantity of the discharged cleaning liquid is admitted into the tank 1. As the level of the cleaning liquid falls, a portion of the substrate 4 is exposed so theft the cleaning liquid on the surface of the substrate 4 is replaced with the fluid, thereby vaporizing the liquid to dry the substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate drying apparatus, and more particularly, to a substrate drying apparatus for supplying a drying fluid to a surface of a substrate to perform Marangoni drying.

[0002]

2. Description of the Related Art Conventionally, as a substrate drying apparatus, as disclosed in Japanese Patent Application Laid-Open No. 6-326073, a drying tank containing a substrate is decompressed and dried in a drying tank together with a carrier gas (eg, nitrogen gas). There has been proposed an apparatus for supplying a steam for drying a surface of an internal substrate.

[0003] When this apparatus is employed, a drying tank (eg, alcohol vapor) which is condensed on the surface of the substrate and replaced with pure water (substrate cleaning liquid) is evaporated by reducing the pressure in the drying tank. Thus, the surface of the substrate can be dried.

A substrate drying apparatus disclosed in Japanese Patent Publication No. 6-103686 has also been proposed. This substrate drying apparatus discharges pure water (substrate cleaning liquid) inside in a state in which high-temperature and high-pressure isopropyl alcohol vapor can be introduced into a container for accommodating a substrate, and discharges isopropyl alcohol with a decrease in pure water in the container. Alcohol vapor can be introduced into the container to replace the residual water film on the substrate surface with isopropyl alcohol vapor to achieve drying of the substrate surface.

[0005]

Problems to be Solved by the Invention Japanese Patent Laid-Open No. 6-32607
In the case of employing the substrate drying apparatus disclosed in Japanese Patent Publication No. 3 (1993) -1995, the concentration of the drying steam is inevitably reduced due to the necessity of the carrier gas. There is a possibility that the entire surface cannot be achieved sufficiently, and if an attempt is made to prevent such inconvenience, a sufficient amount of drying steam and a corresponding amount of carrier gas are supplied. Therefore, the required amount of the carrier gas is significantly increased, which leads to an increase in cost.

Further, when a substrate drying apparatus disclosed in Japanese Patent Publication No. 6-103686 is employed, high-temperature and high-pressure isopropyl alcohol vapor must be generated. Therefore, an apparatus for generating such isopropyl alcohol vapor is required. Is required, which not only complicates the configuration but also increases the cost.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to provide a substrate drying apparatus capable of introducing a sufficient amount of a drying fluid without using a carrier gas. I have.

[0008]

According to a first aspect of the present invention, there is provided a substrate drying apparatus for supplying only a drying fluid to a sealable drying chamber for accommodating a substrate to be dried via a drying fluid guide pipe. And an exhaust means for forcibly discharging gas in the drying chamber.

According to a second aspect of the present invention, the substrate drying apparatus includes, as the drying chamber, an inner chamber for accommodating the substrate and an outer chamber for hermetically surrounding the inner chamber, wherein the inner chamber discharges the substrate cleaning liquid to the outside of the outer chamber. The one having a discharge pipe for carrying out the cleaning is adopted.

[0010]

According to the substrate drying apparatus of the present invention, a drying fluid supply unit for supplying only a drying fluid to a sealable drying chamber for accommodating a substrate to be dried via a drying fluid guide pipe. And the exhaust means for forcibly exhausting the gas in the drying chamber is connected, so that the interior of the drying chamber can be depressurized by exhausting the gas in the drying chamber by the exhaust means. Due to the pressure difference, only the drying fluid can be smoothly introduced into the drying chamber without using a carrier gas, and the surface of the substrate can be dried quickly. In addition, since no carrier gas is used, running costs can be reduced, the piping can be simplified, and the concentration of the drying fluid can be easily reduced to achieve a sufficient substrate drying effect. Can be enhanced.

According to a second aspect of the present invention, the drying chamber includes an inner chamber for accommodating the substrate and an outer chamber for hermetically surrounding the inner chamber, wherein the inner chamber is provided with a substrate cleaning liquid outside the outer chamber. Since a device having a discharge pipe for discharging the substrate cleaning liquid is employed, a certain degree of pressure reduction can be achieved by discharging the substrate cleaning liquid from the inner chamber, but a sufficient pressure reduction cannot be achieved. However, a sufficient pressure reduction is achieved by forcibly exhausting the air inside by the exhaust means, and only the drying fluid is smoothly introduced into the drying chamber without using a carrier gas by the pressure difference due to the pressure reduction, and the substrate is removed. Surface can be dried quickly. Further, since the drying chamber has an inner chamber and an outer chamber that can be sealed, the inner tank can be protected by the outer tank.
Of course, since no carrier gas is used, the running cost can be suppressed, the piping can be simplified, and the concentration of the drying fluid can be easily reduced so as to achieve a sufficient substrate drying effect. Can be enhanced.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a substrate drying apparatus according to an embodiment of the present invention;

FIG. 1 is a schematic view showing an embodiment of a substrate drying apparatus according to the present invention.

This substrate drying apparatus accommodates a substrate 4 and has a drying tank 1 that can be sealed and a drying fluid supply tank 2 connected to the drying tank 1 via a drying fluid supply pipe 2a. And a vacuum pump 3 as exhaust means connected to the drying tank 1 via an exhaust pipe 3a with a valve 3b interposed. In addition, it has a cleaning liquid discharge pipe 1 a for discharging the cleaning liquid from the drying tank 1.

As the drying fluid, isopropyl alcohol vapor can be exemplified, but alcohol vapor other than isopropyl alcohol can also be employed.

The operation of the substrate drying apparatus having the above configuration is as follows.

After a plurality of substrates (semiconductor wafers, etc.) 4 accommodated in the drying tank 1 are washed by supplying a cleaning liquid into the drying tank 1, the drying tank 1 is sealed (in the case where it is already sealed). No sealing work is necessary), the valve 3b is opened, the vacuum pump 3 is operated to discharge gas present in the space of the drying tank 1, and the space is dried by the pressure difference caused by the decompression due to the gas discharge. A working fluid is introduced. Therefore, the head space of the cleaning liquid is filled with the drying fluid.

Thereafter, when the cleaning liquid (pure water) in the drying tank 1 is discharged through the cleaning liquid discharge pipe 1a, the inside of the drying tank 1 is in a reduced pressure state. Is introduced into the drying tank 1. Therefore, when a part of the substrate 4 is exposed from the cleaning liquid as the cleaning liquid level decreases, the substrate 4 is immediately exposed to the drying fluid, and the cleaning liquid on the surface of the substrate 4 is replaced with the drying fluid, and the drying fluid is evaporated. By doing so, quick drying can be achieved. When all the cleaning liquid is discharged from the drying tank 1, the substrate 4
Drying of the entire surface of the sheet can be achieved. During this period, if the pressure reduction is insufficient, the vacuum pump 3 is operated to ensure a sufficient pressure reduction state and supply a sufficient amount of the drying fluid.

In this state, since the inside of the drying tank 1 is filled with the drying fluid, the washing liquid discharge pipe 1
a is communicated with a drying fluid recovery tank (not shown), and a nitrogen gas is supplied from a nitrogen gas supply unit (not shown) to the drying tank 1 to discharge the drying fluid. Thereafter, the drying tank 1 is opened to be dried. The removed substrate 4 can be taken out.

As is clear from the above description, since the carrier gas is not used for introducing the drying fluid, the concentration of the drying fluid is made sufficiently high to increase the drying efficiency and achieve quick drying. And running costs can be reduced. Of course, since the drying fluid and the carrier gas are not mixed, the piping can be simplified.

FIG. 2 is a schematic view showing another embodiment of the substrate drying apparatus of the present invention.

This substrate drying apparatus differs from the substrate drying apparatus of FIG. 1 in that the drying tank 1 is an inner tank 1 for accommodating a substrate 4.
b and a sealable outer tank 1c surrounding the inner tank 1b, and the point that the drying fluid supply tank 2 and the vacuum pump 3 are communicated with the outer tank 1c.

When the substrate drying apparatus having this configuration is employed, the inside of the outer tank 1c is sufficiently depressurized by discharging the cleaning liquid from the inner tank 1b and discharging the gas by the vacuum pump 3. Only the drying fluid can be smoothly introduced, and the surface of the substrate 4 can be dried quickly and evenly.

Further, since the sealing and opening of the outer tank 1c can be performed at a desired timing, the workability of sealing and opening can be improved. Further, it is possible to prevent the cleaning liquid from adhering to the lid of the outer tank 1c.

Further, the inner tank 1b is required to have sufficient resistance to the cleaning liquid when handling various chemicals in common, and is therefore preferably formed of quartz. In this case, the impact resistance of the inner tank 1b is reduced, but since the inner tank 1b is surrounded by the outer tank 1c, the inner tank 1b can be sufficiently protected.

[0026]

According to the first aspect of the present invention, the inside of the drying chamber can be reduced in pressure by exhausting the gas in the drying chamber by the exhaust means, and only the drying fluid is used as the carrier gas by the pressure difference due to the reduced pressure. Can be smoothly introduced into the drying chamber, and the surface of the substrate can be dried quickly.In addition, since no carrier gas is used, running costs can be suppressed and simplification of piping can be achieved. In addition, there is a unique effect that the concentration of the drying fluid can be easily increased so as to achieve a sufficient substrate drying effect.

According to the second aspect of the present invention, sufficient pressure reduction is achieved by forcibly exhausting the internal air by the exhaust means, and the pressure difference caused by the pressure reduction allows only the drying fluid to be smoothly used without using a carrier gas. It can be introduced into the drying chamber to quickly dry the surface of the substrate, and since the drying chamber has an inner chamber and an outer chamber that can be sealed, the outer tank protects the inner tank. In addition, since no carrier gas is used, running costs can be reduced, the simplification of piping can be achieved, and the drying fluid can be sufficiently dried to achieve a sufficient substrate drying effect. This has a specific effect that the concentration can be easily increased.

[Brief description of the drawings]

FIG. 1 is a schematic view showing one embodiment of a substrate drying apparatus of the present invention.

FIG. 2 is a schematic view showing another embodiment of the substrate drying apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drying tank 1a Cleaning liquid discharge pipe 1b Inner tank 1c Outer tank 2 Fluid supply tank for drying 2a Fluid supply pipe for drying 3 Vacuum pump 4 Substrate

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Koji Sumi, Inventor 6-2 Imokunifucho, Yamatokoriyama-shi, Nara Prefecture Toho Kasei Co., Ltd. (72) Dai Awaihara 1304 Kanaokacho, Sakai-shi, Osaka Daikin Industries Inside the Kanaoka Plant (72) Inventor Masao Ohno 1304 Kanaokacho, Sakai City, Osaka Daikin Industries Kanaoka Plant F-term (reference) 3L113 AA01 AB02 AC23 AC24 AC28 AC45 AC46 AC67 BA34 CB16 CB19 DA06 DA10 DA13

Claims (2)

[Claims] A drying fluid guide pipe (2) is provided to a sealable drying chamber (1) for accommodating a substrate (4) to be dried.
A drying fluid supply unit (2) for supplying only the drying fluid is connected via a), and an exhaust means (3) for forcibly discharging gas in the drying chamber (1) is connected. A substrate drying apparatus, comprising: 2. The drying chamber (1) includes an inner chamber (1b) for accommodating the substrate (4) and an outer chamber (1c) for sealingly surrounding the inner chamber (1b). 2.) The substrate drying apparatus according to claim 1, wherein (1) has a discharge pipe (1a) for discharging the substrate cleaning liquid to the outside of the outer chamber (1c).