JPH08141526A - Substrate treatment apparatus and treatment tank used therein - Google Patents

Abstract

PURPOSE: To reduce the inner vol. of a vacuum chamber to a large extent by preventing the re-adhesion of particles to a substrate after the washing of the substrate. CONSTITUTION: When a treatment tank 1 is drained after a substrate 3 is washed with pure water, pure water is discharged from an outer plate 101 while supplied from the bottom part of the treatment tank 1. The treatment tank is partitioned by partition plates 112 and the pure water in the space between them is discharged rapidly as compared with the pure water in the space inside the partition plates 112. As a result, difference in level is generated between the liquid level in the former space and that in the latter space and the pure water of the surface of the latter space flows down to the outside through a through-hole and the liquid level thereof lowers by the overflow of pure water and, therefore, particles floating on the surface of pure water overflow to be discharged and the re-adhesion of particles to the surface of the substrate is prevented. Since drainage is performed while the substrate is stopped within the treatment tank, it is unnecessary to provide a substrate lifting space in a chamber and the inner vol. of the chamber can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing apparatus and a processing bath used for the same, and more specifically, in a semiconductor device manufacturing process, a liquid crystal display manufacturing process, an electronic component-related manufacturing process, etc., a silicon wafer, a glass, etc. The present invention relates to an apparatus for performing a predetermined process (at least a cleaning process and a drying process) on various substrates such as substrates and electronic components, and a processing tank used for the device.

[0002]

2. Description of the Related Art As a method for cleaning various substrates such as silicon wafers using hot water and drying the substrate surface after the cleaning, a method disclosed in, for example, JP-A-3-30330 is conventionally known. Methods are known. In the same publication, a substrate is housed in a chamber, hot water is injected into the chamber to immerse the substrate in the hot water, and then the chamber is depressurized to a vapor pressure of the hot water or less to boil the hot water. After cleaning the substrate by reduced pressure boiling of water, injecting pure water into the chamber after the cleaning, rinsing the substrate with pure water to clean it, draining the water in the chamber, and evacuating the chamber, A substrate cleaning / drying treatment method for drying a cleaned substrate is disclosed. Also,
The publication discloses a technique for effectively preventing dust from adhering to a substrate by supplying nitrogen gas into the chamber at the same time as draining the water when the water in the chamber is discharged.

Further, in JP-A-5-275412, a substrate is housed in a cleaning tank in a chamber, hot pure water is supplied into the cleaning tank from the bottom thereof to overflow from the upper portion thereof, and hot pure water is introduced into the cleaning tank. To form a rising water flow of, the substrate is immersed in the rising water flow of the warm pure water for cleaning, and after the cleaning, the substrate is pulled out of the warm pure water to discharge the warm pure water from the cleaning tank, and then the chamber is evacuated to a vacuum, A substrate cleaning / drying treatment method is disclosed in which the substrate is dried under reduced pressure. Further, in the same publication, in a process of pulling a substrate out of hot pure water, a technique of effectively preventing dust from adhering to the substrate by supplying heated and ionized nitrogen gas to the periphery of the substrate is disclosed. It is disclosed.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the method disclosed in Japanese Patent No. 0330, the substrate is washed with warm water, rinsed with pure water, and then drained from the chamber while the substrate is stationary. In this way, the substrate is drained while the substrate is stationary, and the liquid level in the chamber is lowered to remove water from around the substrate. Particles that have been removed and diffused into the liquid concentrate near the liquid surface. For this reason, when the liquid level falls on the surface of the stationary substrate, there is a problem that particles easily adhere to the surface of the substrate.

On the other hand, in the method disclosed in Japanese Unexamined Patent Publication No. 5-275412, after cleaning the substrate, the substrate is pulled up from the pure water while the pure water overflows from the upper part of the cleaning tank. The particles removed from the surface and diffused in the pure water are discharged from the cleaning tank together with the pure water overflowing from the upper part of the cleaning tank, and the particles do not reattach to the substrate surface when the substrate is pulled up. However, in the method disclosed in the above publication, a space for raising the substrate is provided in the chamber above the cleaning tank.
That is, it is necessary to secure a drying space, and the inner volume of the chamber becomes large. As a result, there is a problem that the size of the apparatus is increased and the cost is increased, and that it takes a long time to reach a predetermined degree of vacuum when the pressure is reduced. Further, in this case, since the substrate transfer position (the transfer position from or to another process) is further above the chamber, the stroke of the lifter for raising and lowering the substrate in the chamber becomes large. As a result, there is a problem that the cost is increased and it is necessary to increase the strength of the lifter.

Therefore, an object of the present invention is to provide a substrate processing apparatus which can prevent particles from re-adhering to the substrate after cleaning the substrate and can significantly reduce the internal volume of the decompression chamber, and a processing bath used therefor. It is to be.

[0007]

The invention according to claim 1 is
A substrate processing apparatus for performing at least a substrate cleaning process and a drying process in the same chamber, wherein a processing tank in which a plurality of substrates are arranged at a predetermined interval is housed in the chamber. The tank is an outer plate that defines the outer wall,
A partition plate provided inside the outer plate with a predetermined gap and having a plurality of through holes formed on the surface thereof, a liquid injection pipe connected to the bottom portion, and a liquid discharge pipe connected to the outer plate. In the drainage process performed after the completion of cleaning of the substrate, pure water is continuously supplied from the liquid injection pipe into the processing tank, and the pure water stored in the processing tank is continuously discharged from the liquid discharge pipe. Is characterized by.

According to a second aspect of the invention, in the invention of the first aspect, the amount of pure water injected into the treatment tank per unit time in the drainage step is defined as the amount of pure water discharged from the treatment tank per unit time. It further comprises a pure water injection amount control means for reducing the amount according to the decrease in the amount.

According to a third aspect of the present invention, in the first aspect of the invention, the diameter of the through hole formed in the partition plate is made smaller from the upper part to the lower part of the partition plate. To do.

According to a fourth aspect of the present invention, there is provided a substrate processing apparatus for performing at least a cleaning process and a drying process on a substrate in the same chamber, wherein the plurality of substrates are accommodated in the chamber and a plurality of substrates are arranged at predetermined intervals. It is provided with a processing tank which is arranged so as to be vacant, a fixed substrate supporting means inside the processing tank, and a movable substrate supporting means which can be raised and lowered between the inside and outside of the processing tank.

According to a fifth aspect of the present invention, there is provided a processing tank in which a plurality of substrates are arranged at a predetermined interval, and each substrate is subjected to at least a cleaning process and a drying process in the same chamber. An outer plate that defines the outer wall, a partition plate that is provided inside the outer plate at a predetermined interval, and has a plurality of through holes formed on the surface thereof, and a liquid injection pipe connected to the bottom portion, With a liquid discharge pipe connected to the outer plate,
In the drainage process performed after the cleaning of the substrate, pure water is continuously supplied from the liquid injection pipe, and pure water stored in the processing tank is continuously discharged from the liquid discharge pipe.

According to a sixth aspect of the present invention, there is provided a processing tank in which a plurality of substrates are arranged at a predetermined interval, and each substrate is subjected to at least a cleaning process and a drying process in the same chamber. In the drainage step performed after the completion of cleaning of the substrate, each of which is composed of a plurality of rotatable plates that are rotatable and includes a divided outer plate that defines an outer wall and a liquid injection pipe connected to the bottom, Pure water is continuously supplied from the liquid injection pipe, and the pure water stored in the processing tank is continuously discharged by rotating the rotary plate in order from the top.

[0013]

In the inventions according to claims 1 and 4, when draining the inside of the processing tank after cleaning the substrate, the pure water is discharged from the outer plate while supplying the pure water from the bottom of the processing tank. ing. Here, since the inside of the processing tank is partitioned by the partition plate, the pure water in the space between the outer plate and the partition plate is discharged faster than the pure water in the space inside the partition plate. . As a result, a level difference occurs between the liquid level in the space between the outer plate and the partition plate and the liquid level in the space inside the partition plate. Therefore, in the space inside the partition plate, the pure water near the surface flows down into the space between the outer plate and the partition plate through the through hole formed in the partition plate. This is completely equivalent to the state where the liquid surface overflows. In this way, since the liquid surface of pure water is constantly overflowing and falling, it is possible to prevent particles floating on the surface of pure water from being discharged together with overflow water and reattaching to the surface of the substrate. In addition, since the drainage can be performed while the substrate is stopped in the processing tank, it is not necessary to separately provide a space for raising the substrate, that is, a drying space in the chamber, and the inner volume of the chamber can be reduced. As a result, the device can be downsized and the cost can be reduced. Further, since the lifting stroke of the lifter for raising and lowering the substrate is shortened, the cost thereof is reduced, which is advantageous in strength.

In the drainage process, the amount of pure water injected per unit time needs to be smaller than the amount of pure water discharged per unit time. However, the amount of pure water discharged per unit time gradually decreases as the liquid level in the processing tank decreases, that is, the water pressure decreases. Therefore, it is necessary to control the amount of pure water injected per unit time by some method. Therefore, in the invention according to claim 2, in the drainage process, the amount of pure water injected into the treatment tank per unit time is reduced according to the decrease in the amount of pure water discharged from the treatment tank per unit time. The pure water injection amount is controlled so as to reduce the amount. Thereby, drainage can be performed while always keeping the liquid level in the space between the outer plate and the partition plate lower than the liquid level in the space inside the partition plate.

In the invention according to claim 3, since the diameter of the through hole formed in the partition plate becomes smaller as it goes downward,
As the liquid level in the processing tank decreases, the amount of pure water that flows down from the space inside the partition plate to the space between the outer plate and the partition plate, that is, overflows, decreases. As a result, the balance between the amount injected into the processing tank and the amount of pure water discharged from the processing tank is adjusted.

In the invention according to claim 4, since the substrate supporting means includes a fixed one inside the processing tank and a movable one between the inside and outside of the processing tank, both of the substrates are supported when the substrate is dried. If it is delivered, the liquid can be uniformly dried without the liquid remaining on the edge of the substrate.

According to the fifth aspect of the present invention, when draining the inside of the processing tank after the cleaning of the substrate is completed, the rotating plates constituting the divided outer plates are sequentially rotated from the top so as to be stored in the processing tank. Pure water is continuously discharged while maintaining the overflow state.

[0018]

1 is a sectional view showing the structure of a substrate processing apparatus according to an embodiment of the present invention. FIG. 2 is a partially cutaway perspective view showing the structure of the processing tank housed in the decompression chamber. The substrate processing apparatus of the present embodiment is similar to the conventional cleaning / drying apparatus in one decompression chamber, and various substrates (silicon wafers for semiconductor integrated circuits, glass substrates for liquid crystal display devices, etc. Substrates for electronic components, etc.)
Although the cleaning treatment and the drying treatment are performed, the chemical treatment for etching and resist film peeling can be performed in the same decompression chamber. This chemical treatment is
Substrates are coated with various chemicals (sulfuric acid, hydrogen peroxide, hydrochloric acid,
Buffered hydrofluoric acid, phosphoric acid, etc.). However, the substrate processing apparatus of the present invention is
It is pointed out in advance that, like the drying device, only the cleaning process and the drying process of the substrate may be performed. In this case, the chemical liquid treatment will be performed by another device as another process. The configuration of the substrate processing apparatus of this embodiment will be described below with reference to FIGS. 1 and 2.

First, referring to FIG. 1, the processing tank 1 is detachably or fixedly housed in a decompression chamber 2. A plurality of sheets (for example,
The (fifty) substrates 3 are arranged in parallel at predetermined intervals. The decompression chamber 2 is composed of a main body 21 that houses the processing tank 1, and a lid 22 that is attached to the upper portion of the main body 21. When the lid 22 is attached to the main body 21, the lid 22 and the main body 21 are brought into close contact with each other by the action of the O-ring 23, and the inside of the decompression chamber 2 is sealed. Further, an IPA (isopropyl alcohol) introducing pipe 24 is attached to the back surface of the lid 22. This I
The PA introduction pipe 24 is the substrate 3 housed inside the processing tank 1.
Array direction (that is, the direction perpendicular to the plane of FIG. 1)
, And both ends thereof penetrate the lid 22 and are connected to an external IPA supply source (not shown).

Next, the structure of the processing tank 1 will be described in more detail with reference to FIGS. 1 and 2. The outer wall of the processing tank 1 is defined by the outer plate 101 and has a substantially rectangular parallelepiped outer shape. The top of the processing tank 1 is open, and the bottom of the processing tank 1 is formed in the shape of an inverted roof with its central portion protruding downward. The inverted roof-shaped ridge line 102 extends along the arrangement direction of the substrates 3. On the outer periphery of the upper part of the outer plate 101,
A receiving plate 103 is provided so as to surround the periphery thereof. The receiving plate 103 cooperates with the upper peripheral edge of the outer plate 11 to form an overflow groove 104 for receiving the liquid (pure water or chemical liquid) overflowing from the processing tank 1. A hole is made in the lower part of the receiving plate 12 near the front end of the processing tank 1, and one end of the overflow drainage pipe 105 is connected to this hole. The other end of the overflow drain is
Although not shown, it penetrates the side surface of the main body of the decompression chamber 2 and is guided to the outside. That is, the overflow groove 10
The pure water (or the chemical liquid) overflowing to 4 is discharged to the outside of the decompression chamber 2 through the overflow drain pipe 105.

An upflow pipe 106 is provided near the front end of the processing tank 1 and below the front end. Although not shown, one end of the upflow pipe 106 has a pressure reducing chamber 2
Is penetrated through the side surface of the main body to be guided to the outside, and is connected to a supply source of pure water and a chemical solution. The other end of the upflow pipe 106 branches left and right at the front end of the processing tank 1 and is connected to the injection inner pipes 107 provided on both left and right sides of the processing tank 1. An outer injection tube 108 is provided so as to surround the outer circumference of the inner injection tube 107 at a predetermined interval. The left and right outer injection tubes 108 extend along the arrangement direction of the substrates 3 and connect the bottom of the processing tank 1 and the left and right side portions. A plurality of holes 107a are formed in the outer circumference of the injection inner tube 107 along the axial direction at predetermined intervals. Each hole 107a is opened in the direction opposite to the substrate 3 in the processing tank. A plurality of slits 108 a are formed on the outer circumference of the outer injection tube 108 at predetermined intervals. Each slit 108a is open toward the substrate 3 in the processing bath. Further, each slit 108 a is arranged so as to be located between each substrate 3. The left and right inner injection pipes 107 and outer injection pipes 108 are terminated near the rear end of the processing tank 1.

A tank drain pipe 109 is provided on the left and right sides of the outer plate 101 and obliquely above the injection outer pipe 108. One end of the in-tank drain pipe 109 is connected to holes 110 formed on the left and right side portions of the outer plate 101. Further, the left and right in-tank drainage pipes 109 are integrated near the front end of the processing tank 1, and the other ends penetrate through the side surface of the main body of the decompression chamber 2 (not shown) to the outside. As a result, the liquid in the processing tank is discharged to the outside through the in-tank drain pipe 109. A three-way switching valve 6 as shown in FIG. 3 is provided in the in-tank drain pipe 109 led to the outside of the decompression chamber 2.
Is attached. The three-way switching valve 6 is configured so that it can be switched between three discharge positions, that is, a minute liquid discharge position, a normal liquid discharge position, and an exhaust position. At the minute liquid discharge position, the liquid in the processing tank is discharged little by little. At the normal drainage position, the liquid in the processing tank is discharged by a normal amount larger than that at the minute drainage position. At the exhaust position, the gas in the processing tank is exhausted.

Inside the processing tank 1, a pair of left and right substrate supporting portions 111 are fixedly provided. These substrate support parts 11
Both ends are fixed to the front end side surface portion and the rear end side surface portion of the inner wall of the outer plate 101. A plurality of grooves are formed in each substrate support portion 111 at predetermined intervals, and the substrate 3 is positioned and supported in the processing tank by inserting the substrate 3 into the grooves.

Inside the processing tank 1, there are provided a pair of left and right partition plates 112 that face the left and right side surfaces of the outer plate 101 with a predetermined gap. Each partition plate 112 has a plurality of holes 112a formed in a matrix. The height of the bottom of each partition plate 112 is equal to
Is higher than the upper position of each slit 108a.
It does not hinder the flow of liquid (especially pure water) emitted from the.

Further, a lifter 4 is provided in association with the processing tank 1 as described above. This lifter 4 is a board guide 4
1 and a lifting device 42 for lifting the substrate guide 41
And a connecting plate 43 that connects the elevating device 42 and the board guide 41. The board guide 41 includes
A plurality of grooves are formed at the same pitch as the grooves formed in the substrate support portion 111 described above, and the substrate 3 is positioned and supported by inserting the substrate 3 into the grooves.

4 to 10 are diagrams showing the operating state of the substrate processing apparatus according to the above embodiment for each step. The operation of the above embodiment will be described below with reference to FIGS.

First, the substrate carrying / loading process will be described with reference to FIG. The transfer robot 5 holds a plurality of substrates 3 for which other steps have been completed by the chuck 51 and transfers them to an upper position of the substrate processing apparatus. At this time, the lid 22 of the decompression chamber 2 is removed, and the substrate guide 41
Is lifted to the upper position of the decompression chamber 2 by the lifting device 42. Next, the transfer robot 5 moves the substrate 3
Is placed on the substrate guide 41, the chuck 51 is rotated in the direction of arrow A, and the substrate 3 is released. As a result, the substrate 3 is supported by the substrate guide 41. Next, the lifter 4 lowers the substrate guide 41 by the elevating device 42. When the substrate guide 41 is lowered to a position lower than the substrate support portion 111 inside the processing tank, the substrate 3 is transferred from the substrate guide 41 to the substrate support portion 111, and the substrate support portion 111 is transferred.
The substrate 3 is supported by. Then, the lid 2 on the main body 21
2 is covered. At this time, the decompression chamber 2 is sealed by the action of the O-ring 23 (see FIG. 1).

Next, with reference to FIG. 5, the chemical treatment step will be described. In the chemical liquid processing step, the chemical liquid is supplied to the upflow pipe 106 from a chemical liquid supply source (not shown) outside the decompression chamber. The upflow pipe 106 guides the supplied drug solution to the injection inner pipe 107. The drug solution introduced into the injection inner pipe 107 is supplied to each hole 1 formed in the injection inner pipe 107.
From 07a, it flows into the inside of the injection outer pipe 108, and further into the processing tank 1 through each slit 108a formed in the injection outer pipe 108. Since the chemical liquid is continuously supplied to the upflow pipe 106 from the external chemical liquid supply source, the liquid level in the processing tank gradually rises and eventually overflows from the upper part of the processing tank. The overflowed chemical liquid flows into the overflow groove 104 and overflows the drain pipe 105.
It is discharged to the outside of the decompression chamber 2 via. Therefore, the substrate 3 is always immersed in a new chemical solution. At this time, the three-way switching valve 6 in FIG. 3 is switched to the minute liquid draining position, and the chemical liquid is also discharged little by little from the in-tank drain pipe 109. As a result, the outer plate 101 and the partition plate 11
The chemical solution does not stay between the two and the concentration with the chemical solution in the processing tank can be made uniform. When a certain reaction time is required, such as etching, in order to reduce the amount of the chemical solution used, the injection of the chemical solution is stopped when the liquid surface reaches a predetermined height. In this case, the three-way switching valve 6 is used. Is closed (that is, the discharge position is not switched to any discharge position), and the discharge of the chemical liquid from the in-tank drain pipe 109 may be stopped.

Next, the cleaning process will be described with reference to FIG. In the cleaning process, pure water is supplied to the upflow pipe 106 from a pure water supply source (not shown) outside the decompression chamber. The upflow pipe 106 guides the supplied pure water to the injection inner pipe 107. The pure water introduced into the injection inner pipe 107 is filled with the holes 10 formed in the injection inner pipe 107.
From 7a, it flows into the inside of the injection outer pipe 108. The pure water that has flowed into the injection outer pipe 108 is ejected into the processing tank 1 through each slit 108 a formed in the injection outer pipe 108.
Here, since each slit 108a is arranged so as to be located between each substrate 3 arranged in the processing tank, the pure water ejected from each slit 108a flows into each substrate. Further, since the substrate support plate 41a extending along the arrangement direction of the substrates 3 is formed in the center of the substrate guide 41, the horizontal pure water flow ejected from each slit 108a hits the substrate support plate 41a. The direction is changed to the upward flow. Therefore, a pure water flow is generated between the substrates in the direction of the arrow shown in FIG. 5, and the surfaces of the substrates are thoroughly cleaned. At this time, the chemical liquid and the pure water overflowing from the upper part of the processing tank flow into the overflow groove 104 and are discharged to the outside of the decompression chamber 2 via the overflow drain pipe 105. Therefore, the particles removed by cleaning from the substrate surface and diffused in the pure water do not stay on the liquid surface and are efficiently discharged to the outside together with the overflow water. At this time, the three-way switching valve 6 in FIG. 3 is switched to the minute liquid draining position. As a result, the chemical liquid accumulated between the outer plate 101 and the partition plate 112 is efficiently discharged to the outside through the in-tank drain pipe 109. Since pure water is continuously supplied to the upflow pipe 106 from an external pure water supply source, the concentration of the chemical liquid in the processing tank gradually decreases, and eventually the liquid in the processing tank becomes pure water only. Then, when the amount of particles contained in the discharged pure water becomes equal to or less than a predetermined amount, the cleaning process ends.

Next, the drainage process, which is a feature of the present invention, will be described with reference to FIGS. 6 and 7. In the drainage process, the three-way switching valve 6 in FIG. 3 is switched to the normal drainage position. On the other hand, the injection of pure water from the external pure water supply source into the processing tank is still continued. At this time, by making the pure water injection amount per unit time smaller than the pure water discharge amount per unit time (pure water injection amount <pure water discharge amount), the outer plate 1
There is a difference between the liquid level of the space between 01 and the partition plate 112 (hereinafter referred to as partition space) and the liquid level of the space inside the partition plate 112 (hereinafter referred to as inner space). . That is, the liquid level of the partition space is lower than the liquid level of the inner space. Therefore, in the pure water in the inner space, the portion near the surface thereof is the hole 1 of the partition plate 112.
It drops into the partition space through 12a (see FIG. 2). Therefore, the liquid surface of pure water in the processing tank descends while always maintaining the overflow state. by this,
It is possible to prevent particles floating on the surface of the pure water from being discharged together with the overflow water and reattaching to the surface of the substrate 3. In other words, the same effect as the conventional technique of pulling up the substrate from pure water whose surface is constantly overflowing (that is, the technique disclosed in Japanese Patent Laid-Open No. 5-275412) can be obtained. As shown in FIG. 7, when the liquid level in the processing tank is completely lower than the substrate 3, the pure water injection is stopped and the pure water in the processing tank is discharged.

Next, the drying process will be described with reference to FIG. In the drying step, IPA vapor is supplied to the IPA introducing pipe 24 from an external IPA supply source (not shown). I
The PA introduction pipe 24 blows out the supplied IPA vapor toward the respective substrates 3 evenly. On the surface of each substrate 3, water droplets are replaced with IPA vapor. That is, IPA lowers the surface tension of water droplets attached to the substrate surface, and therefore the water droplets flow down from the substrate surface due to its own weight. At this time, the three-way switching valve 6 in FIG. 3 is switched to the exhaust position. As a result, the excess gas in the decompression chamber is exhausted, and the IPA gas is efficiently dispersed on each substrate. Note that other organic solvent vapors may be used instead of the IPA vapor as long as it is water-soluble and has a property of lowering the surface tension of water droplets remaining on the substrate. Instead of such organic solvent vapor, heated water vapor may be sprayed to dry the substrate surface. When the replacement of water droplets with IPA on the substrate surface is completed, the supply of IPA vapor is stopped. On the other hand, the exhaust operation via the in-tank drain pipe 109 is continued. As a result, the pressure inside the processing tank is reduced. As a result, the boiling point of the IPA vapor is lowered, IPA replaced with pure on the substrate surface is quickly evaporated, and the substrate surface is dried in a short time.

At this time, the substrate supporting portion 111 and the substrate 3
IPA to remove water droplets that tend to remain on the contact area of
After the vapor is supplied and a certain time has passed, the substrate guide 41
Is slightly raised to receive the substrate 3, the substrate supporting portion 111
The exposed portion of the substrate 3 is exposed, and the portion can be dried well.

Next, the substrate unloading / conveying step will be described with reference to FIGS. First, as shown in FIG. 9, from the main body 21 of the decompression chamber to the lid 2
2 is removed, and the lifter 4 raises the substrate guide 41. As shown in FIG. 10, when the substrate guide 41 moves up to the upper position of the decompression chamber, the transfer robot 5 holds the substrate 3 by the chuck 51 and transfers it to another position.

As described above, in the drainage step, the amount of pure water injected per unit time needs to be smaller than the amount of pure water discharged per unit time. However, the amount of pure water discharged per unit time gradually decreases as the liquid level in the processing tank decreases, that is, the water pressure decreases. Therefore, it is necessary to control the amount of pure water injected per unit time by some method. An example of the control mechanism used for this purpose will be described with reference to FIG. In FIG. 11, a liquid level sensor 71 is provided inside the processing tank 1. This liquid level sensor 71
A minute amount of an inert gas such as nitrogen is supplied to the via a fine pressure gauge 72. Therefore, nitrogen gas bubbles are discharged from the tip of the liquid level sensor 71. The liquid level sensor 71 is covered with a hollow cylindrical cover 76 so that the bubbles of nitrogen gas do not adversely affect the substrate. The micromanometer 72 measures the current liquid level in the processing tank by detecting the discharge pressure of the nitrogen gas from the liquid level sensor 71. The arithmetic circuit 73 calculates the current amount of pure water to be injected into the processing tank per unit time based on the measurement result of the micromanometer 72. The calculation result of the calculation circuit 73 is
It is given to the electropneumatic regulator 74 and converted into pilot air pressure. With this pilot air pressure, the pressure regulator 75 controls the pressure of pure water supplied to the upflow pipe 106, that is, the amount of pure water injected into the processing tank.
As a result, depending on the decrease in the liquid level in the processing tank,
The amount of pure water injected into the processing tank is reduced, and the relationship of (pure water injection amount <pure water discharge amount) is always established.

The above control mechanism is only an example, and the balance between the injection amount and the discharge amount of pure water may be adjusted by another method. For example, the partition plate 112
The diameter of the hole 112a formed in the upper part may be reduced from the upper part to the lower part. In this case, when the liquid level in the treatment tank is high, the amount of pure water flowing from the inner space to the partition space increases, and conversely, when the liquid level in the treatment tank is low, The amount of pure water flowing from the space into the partition space is reduced, and the balance between the pure water injection amount and the pure water injection amount is adjusted.

FIG. 12 shows another embodiment of the processing tank. In the treatment tank of this embodiment, an ultrasonic transducer 8 made of a piezo element or the like is attached to the center of the bottom portion. By driving this ultrasonic transducer during cleaning,
Ultrasonic waves are propagated in the processing bath, thereby enhancing the cleaning effect of each substrate 3. The other structure of this embodiment is shown in FIG.
The processing tank 1 is the same as the processing tank 1 shown in FIG.

FIG. 13 shows still another embodiment of the processing tank. The processing tank of this embodiment is not provided with a partition plate 112 unlike the processing tank 1 shown in FIG. Instead of this, the outer wall of the processing tank 100 is constituted by the divided outer plate 120. The split outer plate 120 is composed of a plurality of rotating plates that are each independently rotatable. When one of the rotating plates is rotated outward from the initial position (while standing vertically), a gap is created in the outer wall at that portion, and pure water in the processing tank is discharged to the outside. There is. Then, by rotating each of the rotating plates outward in order from the top, the liquid level can be lowered while maintaining the overflow state of the pure water surface.

[0038]

According to the inventions of claims 1 to 5, it is possible to lower the substrate while keeping the substrate stationary in the processing tank while constantly overflowing the liquid surface of pure water. As a result, it is possible to prevent particles floating on the surface of the pure water from being discharged together with the overflow water and reattaching the particles to the surface of the substrate. Further, it is not necessary to separately provide a space for raising the substrate, that is, a drying space in the chamber, and the inner volume of the chamber can be reduced. Therefore, the size and cost of the device can be reduced. Further, since the lifting stroke of the lifter for raising and lowering the substrate is shortened, the cost can be reduced, which is advantageous in terms of strength.

Further, according to the second aspect of the present invention, in the drainage process, the amount of pure water injected into the treatment tank per unit time is lower than the amount of pure water discharged from the treatment tank per unit time. The pure water injection amount is controlled so that the liquid level in the space between the outer plate and the partition plate is always kept lower than the liquid level in the space inside the partition plate. Drainage can be done while.

Further, according to the invention of claim 3, the diameter of the through hole formed in the partition plate is made smaller as it goes downward, and as the liquid level in the processing tank becomes lower, the space inside the partition plate becomes smaller. Since the amount of pure water flowing into the space between the outer plate and the partition plate is reduced, the amount of pure water injected into the treatment tank and the amount of pure water discharged from the treatment tank are Balance can always be adjusted to the right relationship.

Further, according to the fourth aspect of the present invention, since the two substrate supporting means change over the substrates during the drying process, there is no part where the substrate and the supporting means constantly contact each other, and the entire substrate can be dried uniformly.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of a substrate processing apparatus according to an embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view showing a configuration of a processing tank housed in a decompression chamber in the embodiment of FIG.

FIG. 3 is a diagram showing a three-way switching valve attached to the in-tank drain pipe 109 in the embodiment of FIG.

FIG. 4 is a diagram showing an operation state at the time of carrying / loading a substrate in the embodiment of FIG.

5A and 5B are diagrams showing operation states in a substrate chemical treatment process and a cleaning process in the embodiment of FIG.

FIG. 6 is a diagram showing an operation state in a drainage process in the embodiment of FIG.

FIG. 7 is a diagram showing an operation state at the end of the drainage process in the embodiment of FIG.

FIG. 8 is a diagram showing an operating state in a substrate drying step in the embodiment of FIG.

FIG. 9 is a diagram showing an operating state at the time of unloading the substrate in the embodiment of FIG.

FIG. 10 is a diagram showing an operation state during the transfer of the substrate in the embodiment of FIG.

FIG. 11 is a diagram showing an example of a mechanism for controlling the injection amount of pure water in conjunction with the decrease in liquid level.

FIG. 12 is a view showing another embodiment of the processing tank.

FIG. 13 is a view showing still another embodiment of the processing tank.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Processing tank 101 ... Outer plate 106 ... Upflow pipe 107 ... Injection inner pipe 108 ... Injection outer pipe 109 ... In-tank drainage pipe 111 ... Substrate support 112 ... Partition plate 112a ... Hole 2 ... Decompression chamber 24 ... IPA introduction Tube 3 ... Substrate 4 ... Lifter 71 ... Liquid level sensor 8 ... Ultrasonic transducer 120 ... Divided outer plate

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location H01L 21/304 351 Z 21/306

Claims (6)

[Claims] 1. A substrate processing apparatus for performing at least a substrate cleaning process and a drying process in the same chamber, wherein a plurality of the substrates are arranged in the chamber at predetermined intervals. Are stored, the processing tank is an outer plate that defines an outer wall, and a partition plate that is provided inside the outer plate with a predetermined interval, and that has a plurality of through holes formed on its surface, A liquid injection pipe connected to the bottom and a liquid discharge pipe connected to the outer plate, and in a drainage step performed after the cleaning of the substrate, pure water is continuously supplied from the liquid injection pipe into the treatment tank. The substrate processing apparatus is characterized in that pure water stored in the processing tank is continuously discharged from the liquid discharge pipe. 2. In the draining step, the amount of pure water injected into the treatment tank per unit time is reduced in accordance with a decrease in the amount of pure water discharged from the treatment tank per unit time. The substrate processing apparatus according to claim 1, further comprising pure water injection amount control means. 3. The substrate processing apparatus according to claim 1, wherein the through hole formed in the partition plate has a diameter that decreases from an upper portion to a lower portion of the partition plate. 4. A substrate processing apparatus for performing at least a cleaning process and a drying process on a substrate in the same chamber, wherein the substrate is housed in the chamber and a plurality of the substrates are arranged at a predetermined interval. A substrate processing apparatus comprising: a processing bath, a fixed substrate support means inside the processing bath, and a movable substrate support means that can move up and down between the inside and the outside of the processing bath. 5. A processing tank in which a plurality of substrates are arranged at predetermined intervals and which performs at least a cleaning process and a drying process on each substrate in the same chamber, and defines an outer wall. An outer plate, a partition plate provided inside the outer plate with a predetermined gap and having a plurality of through holes formed on the surface thereof, a liquid injection pipe connected to the bottom portion, and a connection to the outer plate In a drainage step performed after the cleaning of the substrate is completed, pure water is continuously supplied from the liquid injection pipe, and pure water stored in the processing tank is supplied from the liquid discharge pipe. A treatment tank characterized by being continuously discharged. 6. A processing tank in which a plurality of substrates are arranged at a predetermined interval and in which at least a cleaning process and a drying process are performed on each substrate in the same chamber, each of which rotates. It is composed of multiple possible rotating plates,
In addition, in the drainage step performed after the cleaning of the substrate is completed, pure water is continuously supplied from the liquid injection pipe, and the divided outer plate that defines the outer wall and the liquid injection pipe connected to the bottom are provided. A treatment tank, wherein pure water stored in the treatment tank is continuously discharged by rotating the moving plate in order from above.