JP2000124187A - Substrate drying method and substrate dryer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of a water mark in a substrate by a method wherein, while the substrate is exposed from pure water and/or after exposed, a mist of a water-soluble organic solvent is supplied to the substrate. SOLUTION: A substrate W is dipped in pure water 68 received in a treatment bath 10 to clean the substrate W with water, and if the water cleaning treatment is ended, the substrate W is slowly pulled up from the pure water 68 in the treatment bath 10 by a lifter 30. Opening and closing control valves 52, 76, 80 are opened and also opening and closing control valves 64, 66, 82 are closed, and nitrogen gas and isopropyl alcohol (IPA, fluid) are supplied to a 2-fluid atomizing nozzle 70, and from an atomizing port of the 2-fluid atomizing nozzle 70 toward water face of the pure water 68 in the treatment bath 10, a mist of the IPA which is made foggy with an atomizing pressure of nitrogen gas is atomized together with the nitrogen gas. By this operation, the pure water is replaced completely with the IPA at a vapor-liquid interface on a face of the substrate W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a semiconductor wafer,
Substrates for immersing glass substrates for liquid crystal display devices, electronic components, etc., in pure water contained in a processing tank, washing them, and then pulling them up from pure water or discharging pure water from the processing tank and drying. The present invention relates to a drying method and a substrate drying apparatus used for performing the method.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 6-326073 discloses a method of immersing a substrate such as a semiconductor wafer in pure water contained in a processing bath, washing the substrate with water, and drying the substrate. The substrate after water washing is pulled up from the pure water in the processing tank, or the pure water is discharged from the processing tank while the substrate after the water washing is stopped in the processing tank. Is exposed from pure water,
A water-soluble organic solvent such as isopropyl alcohol (IP) using an inert gas such as nitrogen gas as a carrier gas.
A) The vapor of A) was supplied to the periphery of the substrate, and IPA vapor was condensed at the gas-liquid interface on the surface of the substrate to replace the pure water adhering to the substrate surface with IPA. There is a method in which the inside of the closed chamber is evacuated to a reduced pressure state to evaporate IPA condensed on the surface of the substrate and quickly dry the substrate.

[0003]

However, in the above-described substrate drying method, since IPA is supplied as vapor, the supply amount of IPA becomes insufficient, and pure water is generated at the gas-liquid interface on the surface of the substrate. Cannot be completely replaced with IPA. Therefore, when the substrate is completely exposed from the pure water, there is a problem that the pure water remains on the surface of the substrate and a stain called a watermark occurs after the substrate is dried. Further, in the above method, since the IPA vapor condenses on unnecessary portions such as the inner wall surface of the processing tank and the substrate holder, it is difficult to control the amount of IPA supplied to the surface of the substrate and actually condensed on the substrate surface.

[0004] The present invention has been made in view of the above circumstances, and after immersing a substrate in pure water contained in a processing tank, washing the substrate, and exposing the substrate from the pure water. When drying a substrate in a processing tank, pure water adhering to the surface of the substrate can be completely replaced with a water-soluble organic solvent and the substrate can be dried to prevent the formation of a watermark on the substrate. Also, to provide a substrate drying method capable of easily controlling the amount of the organic solvent supplied to the substrate, and to provide a substrate drying apparatus capable of suitably performing the method. Aim.

[0005]

The invention according to claim 1 is
In a substrate drying method in which a substrate that is immersed in pure water contained in a treatment tank and washed with water is exposed from pure water and dried, the substrate is exposed from pure water and / or after the substrate is exposed. And supplying a mist of a water-soluble organic solvent to the substrate.

According to a second aspect of the present invention, in the substrate drying method according to the first aspect, after supplying a mist of a water-soluble organic solvent to the substrate, the organic mist is transferred to the periphery of the substrate held in the processing tank. It is characterized by supplying a solvent vapor.

According to a third aspect of the present invention, there is provided a substrate pulling means for pulling up a substrate from pure water contained in a processing tank or a water level lowering means for lowering the level of pure water contained in the processing tank. In a substrate drying apparatus for exposing and drying a substrate immersed in pure water contained in the processing tank and washed with water, the substrate was exposed from the pure water and / or was exposed. Mist supply means for supplying a mist of a water-soluble organic solvent to a substrate to be provided is provided.

According to a fourth aspect of the present invention, in the substrate drying apparatus of the third aspect, there is provided a vapor supply means for supplying the vapor of the organic solvent to the periphery of the substrate held in the processing tank, wherein the mist supply means is provided. Switching means for selectively operating the means and the steam supply means.

According to a fifth aspect of the present invention, in the substrate drying apparatus according to the fourth aspect, the mist supply means includes a two-fluid spray nozzle for spraying the organic solvent together with an inert gas. .

According to the substrate drying method of the first aspect of the invention, the water-soluble organic solvent is supplied to the substrate as a mist during or after exposing the washed substrate from pure water. An appropriate amount of the organic solvent is supplied to the substrate. For this reason, since pure water adhering to the surface of the substrate is completely replaced by the organic solvent, when the substrate is completely exposed from the pure water, pure water does not remain on the surface of the substrate. There is no danger that stains called watermarks will occur after drying. In addition, since the organic solvent is supplied to the substrate as a mist, that is, as a liquid, the supply amount can be easily controlled.

In the method for drying a substrate according to the second aspect of the present invention,
By supplying the vapor of the organic solvent to the periphery of the substrate having the organic solvent (liquid) attached to the surface, the evaporation of the organic solvent from the surface of the substrate is promoted.

When the substrate drying apparatus according to the third aspect of the present invention is used, the substrate is pulled up from the pure water stored in the processing tank by the substrate pulling means, or is stored in the processing tank by the water level lowering means. The water level of the pure water is lowered, and the water-washed substrate is exposed from the pure water on the way or after being exposed, and then the water-soluble organic solvent is supplied to the substrate as a mist by the mist supply means. An appropriate amount of the organic solvent is supplied to the substrate.
For this reason, since pure water adhering to the surface of the substrate is completely replaced by the organic solvent, when the substrate is completely exposed from the pure water, pure water does not remain on the surface of the substrate. There is no danger that stains called watermarks will occur after drying. In addition, the organic solvent as a mist,
That is, since the liquid is supplied to the substrate, the supply amount can be easily controlled.

[0013] In the substrate drying apparatus according to the fourth aspect of the present invention,
The vapor supply means supplies the vapor of the organic solvent to the periphery of the substrate having the organic solvent (liquid) attached to the surface, so that the evaporation of the organic solvent from the surface of the substrate is promoted.

[0014] In the substrate drying apparatus of the invention according to claim 5,
By spraying the organic solvent together with the inert gas from the two-fluid spray nozzle, the organic solvent is supplied to the substrate as a mist.

[0015]

Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing an example of a schematic configuration of a substrate cleaning apparatus provided with a substrate drying apparatus used for carrying out the substrate drying method according to the present invention. The substrate cleaning apparatus includes a processing tank 10 having a pure water supply port 12 in a lower part, an overflow part 14 in which pure water overflows in an upper part, and a substrate W which is loaded and accommodated therein. A drain port 16 is formed at the bottom of the treatment tank 10 and the drain port 1 is formed.
A drain pipe 18 in which a drain valve 20 is inserted is connected to and connected to 6. Further, a pure water supply pipe 12 connected to a supply source of pure water is provided in a pure water supply port 12 at a lower portion of the treatment tank 10.
Are connected to each other, and an open / close control valve 24 is provided in the pure water supply pipe 22.

The processing tank 10 is housed in a processing chamber 26 which can carry in and carry out the substrate W by opening and closing the lid 28 and which can be sealed. Inside the processing chamber 26, an elevator 30 for receiving the substrate W carried into the processing chamber 26, inserting it into the processing tank 10, and taking out the processed substrate W from the processing tank 10 is provided. Have been. Also,
A gas-liquid outlet 32 is formed at the bottom of the processing chamber 26, and a gas-liquid outlet pipe 34 is connected to the gas-liquid outlet 32 so as to communicate therewith. The gas-liquid discharge pipe 34 has an open / close control valve 38.
The drain pipe 36 in which the valve is inserted and the exhaust pipe 40 in which the open / close control valve 42 is inserted and connected to the vacuum pump 44 communicate with each other.

A gas blowing nozzle 46 is provided inside the processing chamber 26. The gas blowing nozzle 46 communicates with a gas supply pipe 48 connected to a supply source of an inert gas, for example, nitrogen gas. It is connected. The gas supply pipe 48 is provided with a heater 50, an open / close control valve 52, and a filter 54, respectively.

The gas supply pipe 48 is provided with a bypass pipe 56 which branches at a position between the heater 50 and the opening and closing control valve 52 and joins at a position between the opening and closing control valve 52 and the filter 54. , An organic solvent in the middle of the bypass pipe 56,
For example, an isopropyl alcohol (IPA) 58 is stored and sealed, and an IPA vapor generation tank 60 in which a nitrogen gas inlet of the bypass pipe 56 and an IPA vapor outlet are respectively connected to a closed space above the liquid surface is provided. Opening / closing control valves 64 and 66 are inserted in the bypass pipe 56.
The IPA vapor generation tank 60 contains IPA6 stored inside.
A heater 62 for heating 0 is provided. Then, in the IPA vapor generation tank 60, the IPA is
A60 is heated to generate IPA vapor, and the generated IPA vapor is passed from the bypass pipe 56 to the processing chamber 26 through the gas supply pipe 48 using nitrogen gas as a carrier gas.
It is configured so that it can be supplied to the gas blowing nozzle 46 inside.

Further, a two-fluid spray nozzle 70 is provided inside the processing chamber 26 such that the spray port faces the surface of the pure water 68 contained in the processing tank 10. The two-fluid spray nozzle 70 is connected to a gas supply branch 74 in which an open / close control valve 76 is interposed, and the open / close control valve 8
The IPA supply pipe 78 in which 0 is inserted is connected. The gas supply branch pipe 74 communicates with a gas supply pipe 48 connected to a supply source of nitrogen gas at a position downstream of the filter 54. An open / close control 82 is interposed between the gas outlet nozzle 46 and the gas outlet nozzle 46. On the other hand, the tip of the IPA supply pipe 78 connected to the two-fluid spray nozzle 70 is inserted into the IPA stored in the IPA storage tank 84. And
A mist of IPA atomized by the injection pressure of the nitrogen gas is sprayed together with the nitrogen gas from the spray port of the two-fluid spray nozzle 70.

An example of the structure of the two-fluid spray nozzle 70 is shown in FIG.
FIG. The two-fluid spray nozzle 70 includes an adapter section 92 in which a gas inlet 88 to which the gas supply branch pipe 74 is connected and an IPA inlet 90 to which the IPA supply pipe 78 is connected, an aspirator type IPA supply pipe. It comprises a core portion 94 for sucking IPA from inside 78 to mix IPA with nitrogen gas, a tip 98 having a slit-shaped spray port 96 formed at the tip, and a cap 100 for fixing the tip 98. I have. With such a structure, the IPA is atomized by the injection pressure of the nitrogen gas and is sprayed together with the nitrogen gas from the spray port 96 at the tip of the tip 98. The adapter part 92, the core part 94, the tip 98 and the cap 100 are all formed of stainless steel. Depending on the type of organic solvent used,
The components of the two-fluid spray nozzle 70 need to be made of plastic.

As described above, the substrate drying apparatus of the substrate cleaning apparatus includes a nitrogen gas supply unit, an IPA vapor supply unit,
The apparatus includes a PA mist supply unit and a vacuum exhaust unit. Next, an example of a substrate drying operation performed by using the substrate drying apparatus will be described.

The substrate W is immersed in pure water 68 contained in the processing tank 10 to wash the substrate W with water. When the washing processing is completed, the substrate W is removed from the processing tank 1 by the elevator 30.
Slowly pull it up from the pure water 68 in 0. On this occasion,
The on / off control valves 52, 76, and 80 are opened and the on / off control valves 64, 66, and 82 are closed to supply nitrogen gas and IPA (liquid) to the two-fluid spray nozzle 70, and to process from the spray port of the two-fluid spray nozzle 70 The mist of IPA atomized by the injection pressure of nitrogen gas is sprayed together with the nitrogen gas toward the surface of the pure water 68 in the tank 10. By this operation, the substrate W
Pure water is completely replaced by IPA at the gas-liquid interface on the surface of the substrate. When the substrate W is completely lifted from the pure water 68, the surface of the substrate W is completely replaced by IPA, and pure water does not remain on the surface of the substrate W.

The pure water 14 in the processing tank 10 is moved by the elevator 30.
When the substrate W is completely lifted from the inside, the opening / closing control valve 5 is held while holding the substrate W in the internal space of the processing chamber 26.
2, 76, 80 are closed and the on-off control valves 64, 6
6, 82, IPA using nitrogen gas as carrier gas
The vapor is supplied to the gas blowing nozzle 46, and the IPA vapor is supplied from the gas blowing nozzle 46 to the processing chamber 2 together with the nitrogen gas.
Spout into the internal space of 6. At this time, the drain valve 20 is opened, the pure water 68 in the processing tank 10 is discharged from the drain port 16 through the drain pipe 18, and the gas-liquid discharge pipe 34 and the drain pipe are passed through the gas-liquid discharge port 32 from the bottom of the processing chamber 26. Drain through 36.

Next, the on / off control valves 76, 80 are kept closed and the on / off control valve 82 is kept open, and the on / off control valve 52 is opened and the on / off control valves 64, 66 are closed. The gas is supplied to the gas blowing nozzle 46, and nitrogen gas is blown out from the gas blowing nozzle 46 into the internal space of the processing chamber 26, thereby purging the processing chamber 26 with nitrogen gas. Subsequently, the opening / closing control valves 52 and 82 are also closed to stop the supply of the nitrogen gas to the gas blowing nozzle 46, and then the vacuum pump 44 is driven to drive the processing chamber 26 through the gas-liquid exhaust pipe 34 and the exhaust pipe 40. The inside is evacuated to vacuum, and the substrate W held in the processing chamber 26 is quickly dried under reduced pressure. Thereby, the IP from the surface of the substrate W
A is completely evaporated and removed, and the drying of the substrate W is completed. At this time, since the pure water does not remain on the surface of the substrate W when the substrate W is completely lifted from the pure water 68 as described above, no water mark is generated on the surface of the substrate W. .

When the drying process of the substrate W is completed, the vacuum pump 44 is stopped, and if necessary, a nitrogen gas is supplied into the processing chamber 26. Then, the lid 28 of the processing chamber 26 is opened to remove the substrate W from the processing chamber 26. Remove from inside.

The substrate cleaning method according to the present invention can be carried out in various forms other than the above-described forms. For example, the substrate W being lifted from the two-fluid spray nozzle 70 is
After the mist of A is supplied, if there is no particular need, the operation of injecting the IPA vapor from the gas ejection nozzle 46 into the internal space of the processing chamber 26 is not performed, and only the nitrogen gas is supplied from the gas ejection nozzle 46 to the processing chamber 26. It may be made to squirt into the internal space.

In the above-described embodiment, the substrate W having been subjected to the rinsing process is lifted by the elevator 30 so that the substrate W is exposed from the pure water 68 in the processing tank 10. W is kept stationary in the processing tank 10, the drain valve 20 is opened, and the pure water 68 in the processing tank 10 is slowly discharged from the drain port 16 through the drain pipe 18, and the water level of the pure water 68 in the processing tank 10 is reduced. , The substrate W may be exposed from the pure water 68.

Further, in the above-described embodiment, the IPA mist is supplied to the substrate W while the substrate W having been subjected to the rinsing process is being lifted from the pure water 68 in the processing tank 10. After the W is completely pulled out of the pure water 68 in the processing tank 10, the mist of IPA may be supplied to the substrate W, or the substrate W may be supplied in the pure water 68 in the processing tank 10. IPA mist is supplied to the substrate W while the substrate W is being lifted from the processing tank 1.
The IPA mist may be continuously supplied to the substrate W for a while after being completely pulled up from the pure water 68 in the area 0. Further, it is not always necessary to use the two-fluid spray nozzle 70 as shown in FIG. May be mixed, and a mist of IPA atomized by the injection pressure of nitrogen gas from a normal nozzle may be sprayed together with the nitrogen gas.

[0030]

According to the substrate processing method of the present invention, the substrate is immersed in pure water contained in the processing bath, washed with water, and then exposed from the pure water to remove the substrate from the processing bath. When the substrate is dried with pure water, the pure water adhering to the substrate surface is completely replaced by a water-soluble organic solvent, and pure water remains on the substrate surface when the substrate is completely exposed from pure water. Therefore, it is possible to prevent the formation of a watermark on the dried substrate. Further, since the organic solvent is supplied to the substrate as a mist, that is, a liquid, it becomes easy to control the supply amount of the organic solvent to the substrate.

In the method for drying a substrate according to the second aspect of the present invention,
By evaporating the organic solvent from the surface of the substrate, the substrate can be dried more quickly.

When the substrate drying apparatus according to the third aspect of the present invention is used, the method for drying a substrate according to the first aspect of the present invention can be suitably performed, so that pure water adhering to the surface of the substrate can be completely dissolved in water. Can be replaced with an organic solvent to prevent pure water from remaining on the substrate surface when the substrate is completely exposed from pure water, preventing the formation of a watermark on the dried substrate. Further, it becomes easy to control the supply amount of the organic solvent to the substrate.

In the substrate drying apparatus according to the fourth aspect of the present invention,
By evaporating the organic solvent from the surface of the substrate, the substrate can be dried more quickly.

According to the fifth aspect of the present invention, there is provided a substrate drying apparatus comprising:
The organic solvent can be supplied as a mist to the substrate in a good spray state.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a schematic configuration of a substrate cleaning apparatus provided with a substrate drying apparatus used for performing a substrate drying method according to the present invention.

FIG. 2 is a sectional view showing an example of a structure of a two-fluid spray nozzle which is one of the components of the substrate drying apparatus shown in FIG.

[Explanation of symbols]

W substrate 10 processing tank 12 pure water supply port of processing tank 14 overflow part of processing tank 16 drain port of processing tank 18 drain pipe 20 drain valve 22 pure water supply pipe 24, 38, 42, 52, 64, 66, 76 , 80, 8
2 Opening / closing control valve 26 Processing chamber 28 Processing chamber lid 30 Elevator 32 Gas-liquid outlet of processing chamber 34 Gas-liquid exhaust pipe 36 Drain pipe 40 Exhaust pipe 44 Vacuum pump 46 Gas blowout nozzle 48 Gas supply pipe 50, 62 Heater 54 Filter 56 Bypass pipe 58, 86 Isopropyl alcohol (IPA) 60 IPA vapor generation tank 68 Pure water 70 Two-fluid spray nozzle 74 Gas supply branch pipe 78 IPA supply pipe 84 IPA storage tank

 ──────────────────────────────────────────────────続 き Continuing the front page (72) Inventor Shoshin Matsuda 4-chome Tenjin Kitamachi 1-chome, Horikawa-dori-Terauchi, Kamigyo-ku, Kyoto Dainippon Screen Mfg. Co., Ltd. (72) Inventor Koji Hasegawa Kyoto 4-chome Tenjin, Horikawa-dori-Teranouchi, Kamigyo-ku, Tokyo 1-1-1 Kitamachi Dainippon Screen Mfg. Co., Ltd. F-term (reference) 3L113 AA01 AB02 AC08 AC30 AC48 AC67 BA34

Claims (5)

[Claims] 1. A substrate drying method for exposing a substrate immersed and rinsed in pure water contained in a treatment tank from pure water and drying the substrate, wherein the substrate is exposed from the pure water and / or Alternatively, a mist of a water-soluble organic solvent is supplied to the substrate after being exposed. 2. The method for drying a substrate according to claim 1, wherein after the mist of the water-soluble organic solvent is supplied to the substrate, the vapor of the organic solvent is supplied to the periphery of the substrate held in the processing tank. 3. The apparatus according to claim 1, further comprising a substrate pulling means for pulling up the substrate from the pure water contained in the processing tank or a water level lowering means for lowering the water level of the pure water stored in the processing tank. In a substrate drying apparatus for exposing and drying a substrate immersed in pure water and washed with water, the substrate is exposed from the pure water and / or to a substrate after being exposed. A substrate drying device comprising a mist supply unit for supplying a mist of a water-soluble organic solvent. 4. A vapor supply means for supplying the vapor of the organic solvent to the periphery of the substrate held in the processing tank, wherein a switching means for selectively operating the mist supply means and the vapor supply means is provided. The substrate drying apparatus according to claim 3, wherein the apparatus is provided. 5. The substrate drying apparatus according to claim 3, wherein the mist supply unit includes a two-fluid spray nozzle for spraying the organic solvent together with an inert gas.