JP2000031103A - Method of cleaning, method of replacing cleaning solution, cleaning apparatus and cleaning bath - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize high efficiency in cleaning and in replacement of cleaning solution, by moving a partitioning plate in a cleaning bath in which wafers to be cleaned are immersed when the cleaning solution is fed to the cleaning bath. SOLUTION: A deionized-water rinse bath (cleaning bath) 1 is provided with a wafer-holding jig for holding a plurality of wafers 5, a deionized water straightening plate, and a movable partitioning plate 8 in the bath body 4, which has an opening for feeding deionized water from the bottom to feed deionized water to let it overflow. The partitioning plate 8 has a planar form, which is the same as the inner planar form of the bath body 4, and is a board having a plurality of openings 8a, through each of which each of the plurality of wafers loaded inside of the bath body 4 can be transferred, wherein the wafers are loaded within a slightly smaller cross-sectional area than the cross- sectional area of the bath body 4. The partitioning plate 8 can be moved up and down in the bath body 4, and by moving the partitioning plate in the bath body, it is possible to keep purity of the cleaning solution adequately to realize high-efficiency cleaning.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning method for cleaning a wafer such as a semiconductor wafer, a cleaning liquid replacement method, a cleaning apparatus, and a cleaning tank.

[0002]

2. Description of the Related Art In cleaning semiconductor wafers, various types of chemicals are generally used, and during the processing of various types of chemicals, a pure water rinse is generally required to prevent mixing of the chemicals. Also,
At the end of cleaning, pure water rinsing is most often performed before drying.

In a general cleaning apparatus, one cleaning tank is used for one.
Only one chemical (or pure water rinse) is processed.
On the other hand, a cleaning method in which two or more processes such as chemical solution treatment and pure water rinsing are performed in one cleaning tank is also known.

[0004]

By the way, in the immersion type cleaning, when a semiconductor wafer enters a pure water rinsing tank, which is one of the cleaning tanks, the purity of the pure water is reduced by a chemical solution brought into the wafer. It takes time to go up.
This is because even if the pure water supply method is devised so that the flow of pure water in the rinsing tank becomes laminar, the wafer or wafer carrier enters the rinsing tank and becomes a resistance to the flow of pure water. This is because turbulence in the tank is generated in the rinsing tank by being disturbed. When convection in the tank occurs, impurities in the rinsing tank cannot be efficiently discharged. Therefore, it is important to control the flow in the rinsing tank.

On the other hand, when performing two or more treatments in one cleaning tank, it is necessary to replace the liquid in the cleaning tank. In that case, a method is known in which these processes are performed continuously without exposing the wafer to the atmosphere. In such a case, it is necessary to drive out the previous cleaning liquid with the next cleaning liquid (for example, pure water or a different chemical liquid). A large amount of cleaning solution is required.

In addition, when pure water rinsing is performed after chemical treatment in one tank, for example, the time required for pure water rinsing is many times longer than when the chemical tank and the pure water rinsing tank are separated. There is a problem.

In view of the above, the present invention provides a cleaning method, a cleaning liquid replacement method, a cleaning apparatus, and a cleaning tank that enable efficient cleaning and cleaning liquid replacement in wafer cleaning.

[0008]

According to the cleaning method of the present invention, a partition plate is moved in a cleaning tank in which a wafer to be cleaned is immersed when a cleaning liquid is supplied.

In the cleaning method of the present invention, the cleaning liquid supplied to the cleaning tank while being blocked by the partition plate is kept at a high purity. By moving the partition plate together with the supply of the cleaning liquid, the area of the high-purity cleaning liquid increases, and finally, the cleaning with the high-purity cleaning liquid is performed.

In the cleaning liquid replacement method according to the present invention, a second cleaning liquid is supplied while discharging the first cleaning liquid in the cleaning tank in a state where the wafer to be cleaned is immersed, and the cleaning tank is supplied when the second cleaning liquid is supplied. The cleaning liquid is replaced with the second cleaning liquid by moving the inner partition plate.

In the cleaning liquid replacement method of the present invention, the first cleaning liquid and the second cleaning liquid are separated from each other by the partition plate. Then, the second cleaning liquid is sequentially increased by the movement of the partition plate, and finally, the first cleaning liquid is completely discharged in a state where the wafer to be cleaned is set in the cleaning tank, and the second cleaning liquid is filled in the cleaning tank.
Is replaced by the washing liquid.

The cleaning apparatus according to the present invention is provided with a cleaning tank provided with a partition plate which moves inside the tank when supplying the cleaning liquid.

In the cleaning apparatus of the present invention, the wafer to be cleaned is immersed in the cleaning liquid in the cleaning tank, and the partition plate moves with the supply of the cleaning liquid. The cleaning liquid supplied by the partition plate is partitioned and maintained at a high purity, and the high-purity cleaning liquid increases as the partition plate moves, so that the wafer to be cleaned is finally efficiently cleaned with the high-purity cleaning liquid.

The cleaning tank according to the present invention has a configuration having a partition plate which moves in the tank when the cleaning liquid is supplied.

In the cleaning tank of the present invention, the wafer to be cleaned is immersed in the cleaning liquid in the cleaning tank during cleaning, and the partition plate moves together with the supply of the cleaning liquid into the cleaning tank. At this time, the partition plate separates the cleaning liquid already supplied into the tank from the cleaning liquid supplied later without being mixed, so that the tank is quickly filled with the high-purity cleaning liquid, and efficient cleaning is performed. Done.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cleaning method according to the present invention is a cleaning method in which a wafer to be cleaned is immersed in a cleaning liquid in a cleaning tank for cleaning, and a partition plate is moved in the cleaning tank when the cleaning liquid is supplied.

The partition plate moves from the cleaning liquid supply side to the cleaning liquid discharge side.

According to the present invention, in the above-mentioned cleaning method, the partition plate is moved upward from below when the overflow of the cleaning liquid is supplied.

According to the present invention, in the above-described cleaning method, the partition plate is moved from top to bottom when the cleaning liquid is supplied in a down flow.

According to the present invention, in the above cleaning method, the supply amount of the cleaning liquid is L [cm ³ / min], and the moving speed of the partition plate is V
[Cm / min], and the cross-sectional area of the washing tank is S [cm ² ].
The supply amount of the cleaning liquid and the moving speed of the partition plate are controlled so as to satisfy L ≧ V × S.

The cleaning liquid used in the above-described cleaning method is, for example, a rinsing liquid (eg, pure water), a chemical liquid, or the like.

In the cleaning liquid replacement method according to the present invention, the second cleaning liquid is supplied into the cleaning tank while discharging the first cleaning liquid while the wafer to be cleaned is immersed in the first cleaning liquid in the cleaning tank. Then, when supplying the second cleaning liquid, the partition plate is moved in the cleaning tank to replace the cleaning liquid in the cleaning tank with the second cleaning liquid.

According to the present invention, there is provided the above-mentioned method for replacing a cleaning solution,
The supply amount of the second cleaning liquid is L [cm ³ / min], the moving speed of the partition plate is V [cm / min], and the sectional area of the cleaning tank is S [cm].
² ], the supply amount of the second cleaning liquid and the moving speed of the partition plate are controlled so as to satisfy L ≧ V × S.

This cleaning liquid replacement method can be applied to cleaning liquid replacement when two or more treatments such as chemical treatment and rinsing (for example, pure water) treatment are performed in the same washing tank. For example, when performing a pure water rinsing process after a chemical solution process, and performing a chemical solution process after the pure water rinsing process, a first chemical solution process, a pure water rinsing process, a second chemical solution process, and a pure water rinsing process are sequentially performed. In addition, when the second chemical treatment is performed after the first chemical treatment, any other combination processing may be considered.

The first cleaning liquid in the above-mentioned cleaning liquid replacement method corresponds to the cleaning liquid previously stored in the cleaning tank, and the second cleaning liquid corresponds to the cleaning liquid supplied later. The first and second cleaning liquids can be selected from a chemical liquid and a rinsing liquid.

The cleaning apparatus according to the present invention is provided with a cleaning tank provided with at least one movable partition plate which moves in the tank when supplying the cleaning liquid.

According to the present invention, in the above cleaning apparatus, the supply amount of the cleaning liquid is L [cm ³ / min], and the moving speed of the partition plate is V
[Cm / min], and the cross-sectional area of the washing tank is S [cm ² ].
The supply amount of the cleaning liquid and the moving speed of the partition plate are controlled so as to satisfy L ≧ V × S.

The cleaning tank according to the present invention has a structure in which at least one movable partition plate that moves in the tank when the cleaning liquid is supplied is provided.

According to the present invention, in the cleaning tank, the supply amount of the cleaning liquid is L [cm ³ / min], the moving speed of the movable partition plate is V [cm / min], and the cross-sectional area of the cleaning tank is S [cm ^2]. ], The supply amount of the cleaning liquid and the moving speed of the partition plate are controlled so as to satisfy L ≧ V × S.

The cleaning liquid for the cleaning tank may be a rinsing liquid.

As the cleaning liquid for the cleaning tank, a chemical solution can be used.

According to the present invention, a plurality of different cleaning liquids, for example, a chemical liquid, a rinsing liquid and the like can be selectively supplied to the cleaning tank.

An embodiment in which the present invention is applied to a carrierless batch type immersion cleaning will be described below with reference to the drawings.

In the carrierless batch type immersion cleaning device,
For example, when the semiconductor wafer is set in the cleaning device and the chemical cleaning process in the chemical bath is completed, the semiconductor wafer is then transferred to a pure water rinsing bath, immersed in pure water in the pure water rinsing bath, and rinsed with pure water. Is performed. When the pure water rinsing is completed, the semiconductor wafer is taken out of the pure water rinsing bath, and the next cleaning process is performed.

In the cleaning device according to the present embodiment,
In particular, a cleaning tank, for example, a pure water rinsing tank is configured with a special structure.

FIGS. 1 and 2 show an embodiment of a pure water rinsing tank according to the present invention. This pure water rinsing tank 1 is a so-called overflow rinsing tank that supplies pure water from below and causes overflow, and is provided in a tank body 4 having a pure water supply port 3 for supplying pure water 2 at a lower part. It is configured by arranging a wafer holder 6 for holding a plurality of semiconductor wafers 5, a pure water rectifying plate 7, and a movable partition plate 8.

The pure water straightening plate 7 is arranged close to the bottom where the pure water supply port 3 faces, and the pure water 2 supplied from the pure water supply port 3 is provided.
Is formed into a laminar flow, for example, a large number of openings such as slits, grids, or circles are formed on the entire surface of the plate.

The movable partition plate 8 has the same planar shape as the internal planar shape of the tank main body 4 and has an area slightly smaller than the internal cross-sectional area thereof. 5 is formed of a plate-like body having a plurality of openings 8a formed therein so as to be inserted therein, and is arranged to be able to move up and down in the tank body 4.

Next, along with the operation of the pure water rinsing tank 1,
A cleaning operation and a cleaning method of the cleaning device of the present embodiment will be described.

As shown in FIG. 3A, the plurality of semiconductor wafers 5 having undergone the chemical cleaning process are transferred to the overflowing pure water rinsing tank 1 through which pure water 2 is supplied from the lower pure water supply port 3 and overflows. It is set on the wafer holder 6 in the pure water rinsing tank 1. The semiconductor wafer 5 is rinsed by overflow of pure water supplied from the pure water supply port 3 below the tank body 4.

Here, what needs to be done by overflowing the pure water 2 is to wash out the chemical solution on the surface of the semiconductor wafer 5 and to remove the chemical solution brought into the pure water rinsing tank 1 by the surface of the semiconductor wafer 5 and the transfer jig. It is to drive out of the rinsing tank 1. By the way, immediately after the semiconductor wafer 5 is immersed in the pure water rinsing tank 1, the introduced chemical liquid spreads in the rinsing tank 1 due to the turbulence caused by the introduction of the semiconductor wafer 5, and the purity of the pure water 2 is reduced. Will fall. However, in this embodiment, at this time, the pure water 2 overflows from the pure water supply port 3 through the openings of the pure water straightening plate 7 and the movable partition plate 8.

As shown in FIG. 3B, when the pure water 2 is continuously supplied from the pure water supply port 3, an area surrounded by the bottom of the rinsing tank 1 and the movable partition plate 8 by the action of the pure water straightening plate 7. The purity of the pure water 2 of a ₁ (shown in white) is improved.

Next, as shown in FIG. 3C, a region a ₁ including the pure water supply port 3, the pure water straightening plate 7, and the movable partition plate 8 is provided.
After the purity of the pure water 2 becomes sufficiently high, the movable partition plate 8 is raised while supplying the pure water 2. The movable partition plate 8 does not interfere with the semiconductor wafer 5 because the semiconductor wafer 5 is inserted into the opening 8a even when the movable partition plate 8 is raised.

Here, the supply amount of the pure water 2 is set to L [cm ³ /
Min], the rising speed of the movable partition plate 8 is V [cm / min],
When the sectional area of the pure water rinsing tank 1 (that is, the cross-sectional area of the tank body 4 cut horizontally) is S [cm ² ], L ≧ V × S is satisfied. Preferably, the pure water supply amount L is V × S
It is better to make it larger.

The pure water supply amount L so as to satisfy L ≧ V × S
When the rising speed V of the movable partition plate 8 is set, the volume of the area a ₁ between the movable partition plate 8 and the bottom of the pure water rinsing tank 1 increases when the movable partition plate 8 rises. ,
Since the pure water for filling this volume is supplemented by at least the pure water 2 supplied from the pure water supply port 3, the pure water 2 in the area b ₁ (shown by oblique lines) above the movable partition plate 8 is movable. It does not enter the pure water 2 in the area a ₁ below the partition plate 8.

Therefore, the area a below the movable partition plate 8
The pure water 2 of ₁ can always maintain a high purity state. Even if turbulence occurs in the area b ₁ above the movable partition plate 8, the turbulent flow is blocked by the movable partition plate 8 and does not enter the area a ₁ below the movable partition plate 8.

Next, as shown in FIG. 3D, when the movable partition plate 8 comes out of the upper part of the pure water rinsing tank 1, the rinsing is completed. After that, the semiconductor wafer 5 is taken out of the pure water rinsing tank 1 and the next processing is performed.

According to the above-described embodiment, during the pure water rinsing treatment by the overflow rinsing tank 1, the movable partition plate 8 is raised from the bottom to the top in the tank main body 4 so as to satisfy L ≧ V × S. By moving, the turbulence in the tank main body 6 is suppressed, and the purity of the pure water 2 in the area a ₁ below the movable partition plate 8 is increased while efficiently discharging impurities in the rinsing tank. Rinsing can be performed. Therefore, the effect of pure water rinsing due to overflow can be enhanced, the amount of pure water 2 used can be reduced, and the time required for pure water rinsing can be shortened. That is,
The pure water rinsing process can be performed efficiently.

FIGS. 4 and 5 show another embodiment of the pure water rinsing tank according to the present invention. This pure water rinsing tank 11
A plurality of, in this example, two movable partitioning plates 8A and 8B having the same configuration are arranged in the tank body 4 and configured.
Other configurations are the same as those in FIGS. 1 and 2, and corresponding portions are denoted by the same reference numerals, and redundant description will be omitted.

It is preferable that the two movable partition plates 8A and 8B move with a time lag from each other. In this case, the speeds of the two movable partition plates 8A and 8B may not be the same, at least the supply amount L of pure water 2 [cm ³ / min], and the rising speed V [cm / min] of the movable partition plates. ], Each movable partition plate 8 is defined as a sectional area S [cm ² ] of the tank body 4.
A and 8B should satisfy L ≧ V × S.

The pure water rinsing tank 11 operates as follows. As shown in FIG. 4A, the plurality of semiconductor wafers 5 having been subjected to the chemical solution cleaning process have pure water 2 in a lower pure water supply port 3.
Water rinsing tank 11 supplied from and overflowing
And set on the wafer holder 6 in the pure water rinsing tank 11. The semiconductor wafer 5 is rinsed by the overflow of the pure water 2 supplied from the pure water supply port 3.

Then, as shown in FIG. 4B, by supplying pure water 2 from the pure water supply port 3, an area a ₂ surrounded by the movable partition plates 8A and 8B and the bottom of the rinsing tank 11 (shown in white) After the purity of the pure water 2) becomes sufficiently high, the first movable partition plate 8A is raised while supplying the pure water 2 as shown in FIG. 4C.

Subsequently, as shown in FIG. 4D, the second movable partition plate 8B is raised with a time lag from the first movable partition plate 8A. First and second movable partition plates 8A
And the rise of 8B, the purity of the pure water 2 in the region b ₂ (illustrated by the oblique lines) between the first and second movable partition plates 8A and 8B is increased in the region c ₂ above the first movable partition plate 8A. higher than the purity of the pure water 2 (densely hatched shown), further the rinsing tank 11 bottom and the purity of the pure water 2 regions a ₂ between the second movable partition plate 8B is pure water 2 region b ₂ Higher than purity.

Next, as shown in FIG. 5E, the first movable partition plate 8A comes out above the pure water rinsing tank 11. Subsequently, as shown in FIG. 5F, when the second movable partition plate 8B comes out of the upper part of the pure water rinsing tank 11, the pure water rinsing process ends. Thereafter, the semiconductor wafer 5 is taken out of the pure water rinsing tank 11 and the next processing is performed.

According to the rinsing treatment by the pure water rinsing tank 11, the purity of the pure water 2 can be further increased by raising the two movable partition plates 8A and 8B with a time difference therebetween, and furthermore, the pure water can be further purified. The water rinsing effect is enhanced and good rinsing can be performed. In addition, the amount of pure water used can be reduced, and the time for pure water rinsing can be reduced in the same manner as described above.

Although two movable partition plates 8A and 8B are provided in FIGS. 4 and 5, three or more movable partition plates are provided as necessary, and each movable partition plate is separated by a time difference. It can be placed and moved to further improve the purity.

FIG. 6 shows still another embodiment of the pure water rinsing tank according to the present invention. The pure water rinsing tank 13 is a so-called down-flow rinsing tank for supplying pure water from above to down-flow.

In the pure water rinsing tank 13, a tank main body 16 is formed by an inner tank 14 in which the semiconductor wafer 5 to be cleaned is immersed and an outer tank 15 provided on the outer periphery of the upper part of the inner tank 14. A drain port 17 is provided at the bottom of the inner tank 14, and a pure water supply port 18 is provided at a lower part of the outer tank 15. Pure water 2
The water flows from the pure water supply port 18 through the outer tank 15 through the inner tank 14 from above to below, and is drained from the drain port 17. The drainage may be free fall or may be suctioned by a pump.

In the inner tank 14, the wafer holder 6 and the pure water straightening plate 7 are arranged. Furthermore, this pure water rinsing tank 1
3, a movable partition plate 8 that can move in the inner tank 14 when pure water is supplied is provided. The movable partition plate 8 is initially at a position outside the outer tub 15, and is lowered in the inner tub 14 from top to bottom by rinsing.

The lowering speed V of the movable partition plate 8 [cm / cm
Min], the supply amount of pure water may be L [cm ³ / min] and the cross-sectional area S [cm ² ] of the inner tank 14 may satisfy L ≧ V × S.

The down-flow pure water rinse tank 13
It works as follows. As shown in FIG. 6A, the semiconductor wafer 5 that has completed the chemical solution cleaning process and requires a pure water rinsing process
Is immersed in the inner tank 14 in which the pure water 2 is flowing down, and is set on the wafer holder 6. At this time, the movable partition plate 8 is waiting outside the outer tank 15.

Next, as shown in FIG. 6B, after the semiconductor wafer 5 is immersed and after a certain period of time, the movable partition plate 8 is inserted into the inner tank 14 from the top, and is directed toward the bottom of the inner tank 14. It descends slowly at the descending speed V satisfying the above L ≧ V × S. Then, as shown in FIG. 6C, when the movable partition plate 8 advances in the inner tank 14, the volume of the region a ₃ (shown in white) above the movable partition plate 8 increases, Since the pure water 2 is supplied as described above, the purity of the pure water 2 is always kept high in the area a ₃ above the movable partition plate 8. That is, the purity of the region a ₃ is higher than the purity of the region b ₃ below the movable partition plate 8.

Next, as shown in FIG. 6D, when the movable partition plate 8 reaches the bottom of the inner tank 14, the pure water rinsing is completed. After that, the semiconductor wafer 5 is taken out from the inner tank 14 and the next processing is performed.

Also in this embodiment, during the pure water rinsing process in the downflow rinsing tank 13, the movable partition plate 8 is moved downward from above in the inner tank 14 so as to satisfy L ≧ V × S. by impurities efficiently discharged while pure water rinse to enhance the purity of the pure water 2 in the region a ₃ above the movable partition plate 8 to suppress the turbulence in the inner tank 14 in the rinsing tank It can be performed. Therefore, the effect of pure water rinsing by the down flow can be enhanced, and at the same time, the amount of pure water 2 used can be reduced and the time for pure water rinsing can be reduced.

As described above, this down blow rinse tank 13 can also be configured such that two or more movable partition plates 8 are provided, and each movable partition plate 8 is moved with a time lag. .

On the other hand, there is a cleaning method in which a single cleaning tank performs a plurality of processes such as a chemical process and a pure water rinsing process. In such a case, the present invention can be used. The operation and principle in this case are the same as those described above.

Referring to FIGS. 7 and 8, an embodiment of a cleaning method and a cleaning apparatus for performing a plurality of processes in one cleaning tank will be described.

The cleaning tank 21 shown in FIGS. 7 and 8 has the same configuration as the pure water rinsing tank 11 shown in FIG. That is, the cleaning tank 21 is an overflow cleaning tank, in which a cleaning liquid supply port 23 for supplying a chemical solution and pure water is provided at the bottom of the tank main body 4, and the rectifying plate 7 and the wafer holder 6 are provided in the tank main body 4. , A plurality of movable partition plates 8, in this example, two movable partition plates 8A and 8B and the like.

Next, the cleaning operation will be described. As shown in FIG. 7A, the semiconductor wafer 5 is immersed in the tank body 4 filled with the chemical solution 26, and a cleaning process using the chemical solution 26 is performed.

Next, when starting pure water rinsing, pure water 2 is supplied from the cleaning liquid supply port 23 as shown in FIG. 7B.
When the supply of the pure water 2 is started, the bottom of the tank body 4, the current plate 7,
Movable partition plate 8A, due to the low amount of space a ₄ surrounded by 8B, also, since the movable partition plates 8A, chemical 26 filled in the upper portion of the tank body 4 by 8B does not flow back, movable partition plate 8A, the purity of the pure water 2 in the region a ₄ to bottom 8B is easily improved.

Next, as shown in FIG. 7C, the movable partition plate 8A is raised. This rising speed V ₁ [cm / min]
Means that the supply amount of pure water 2 is L ₁ [cm ³ / min]
(Thus, the cross-sectional area of the tank body 4) is S [cm ² ] and L ₁
It suffices to satisfy ≧ V ₁ × S. If this formula is satisfied, the area a ₄ (shown in white) below the movable partition plate 8A is always filled with pure water 2 having high purity.

Next, as shown in FIG. 7D, when the movable partition plate 8A comes to the upper part of the cleaning tank 21, the replacement of the pure water 2 is completed. Then, the pure water rinsing process ends.

Further, when the next chemical treatment is performed, FIG.
As shown in FIG. 7, the chemical solution 26 of FIG.
Is supplied. When the supply of the chemical solution 27 is started, the bottom of the tank main body 4, the current plate 7, the movable partition plate 8B
Because the capacity of the area b ₄ (shown by oblique lines) surrounded by is small, and because the pure water 2 filled in the upper area a ₄ of the tank body 4 does not flow backward by the movable partition plate 8B, the movable partition plate 8B The concentration of the chemical 27 in the region b ₄ below is not diluted by the pure water 2.

Next, as shown in FIG. 8F, the movable partition plate 8B is raised. The rising speed V _{2 of the} partition plate 8B
[Cm / min] means that the supply amount of the chemical solution 27 is L ₂ [cm ³ /
Min], and the sectional area of the tank body 4 is S [cm ² ], and L ₂ ≧
V ₂ × S may be satisfied. This region b ₄ below the movable partition plate 8B satisfy the equation is always filled with the liquid chemical 27 in the supplied concentration.

Next, as shown in FIG. 8G, when the movable partition plate 8B comes to the upper part of the tank body 4, the replacement with the chemical solution 27 is completed. After this state, the chemical 27
Whether to stop supplying or keep supplying is selected according to the processing content.

After the cleaning process with the chemical solution 27 is completed,
The same pure water rinsing process as in FIGS. 7B to 7D is performed.

Next, after the chemical solution treatment and the pure water rinsing treatment in the cleaning tank 21 are completed, the semiconductor wafer 5 is taken out from the cleaning tank 21 and the next processing such as drying is performed.

During the operation described above, the movable partition plate 8 moves several times from the bottom of the cleaning tank to the upper portion. As the movable partition plate, a plurality of movable partition plates are prepared in advance at the bottom as shown in the drawing, or One movable partition plate may be used by moving the movable partition plate to the bottom by lowering the movable partition plate after pure water rinsing, or by moving the movable partition plate to the bottom portion after chemical liquid replacement. .

According to this embodiment, one cleaning tank 2
When performing a plurality of cleaning treatments in step 1, a cleaning liquid such as pure water 2
Partition plate 8 [8A, 8]
B], the effect of replacing the pure water 2 and the chemical solution 27 is increased. In addition, the amount of pure water 2 and chemical solution 27 used can be reduced. Further, the processing time of the pure water rinsing can be particularly reduced.

The chemical 26 shown in FIG. 7A and the chemical 27 shown in FIG.
However, if necessary, the two can be the same chemical solution. If pure water rinsing is not required after the chemical solution treatment of FIG. 8G, the semiconductor wafer 5 can be taken out after the treatment of FIG. 8G and the next treatment can be performed.

The movable partition plate 8 in each of the above embodiments.
As the shape of [8A, 8B], a plate-shaped opening 8a through which the semiconductor wafer 5 can be inserted is used. In addition, a movable partition plate shown in FIGS. 9 to 12 is used. You can also. The movable partition plate 8 shown in FIGS. 9A and 9B is formed by forming a large number of pores 8b in other portions in addition to the opening 8a through which the semiconductor wafer 5 can be inserted.

The movable partition plate 8 shown in FIGS. 10A and 10B
It is formed in a frame shape having an opening 8c in a region corresponding to the plurality of semiconductor wafers 5. In particular, the cleaning liquid does not easily flow in a portion where the plurality of semiconductor wafers 5 are gathered, and the cleaning liquid mainly flows easily in the peripheral portion of the semiconductor wafer group. Therefore, the frame-shaped movable partition plate 8 also has a sufficient partitioning function. .

As the movable partition plate 8, at least
It is more efficient to make the opening as small as possible.

As the movable partition plate 8, FIG.
Instead of a flat plate shape as shown in FIG. Further, as shown in FIG. 12, the movable partition plate 8 may be arranged to be inclined. Movable partition plate 8
When the movable partition plate 8 comes to the upper part of the tank main body 4 when the is bent or inclined, the cleaning liquid flows down without collecting on the partition plate 8. In addition, a rectifying action can be promoted.

The cleaning tanks shown in FIGS. 1 to 6 and 9 to 12 are applied to a pure water rinsing tank.
It can also be applied to a cleaning tank for chemicals.

In the above embodiment, the present invention is applied to cleaning of a semiconductor wafer, but can be applied to cleaning of other wafers.

[0087]

According to the cleaning method of the present invention, by supplying the cleaning liquid and moving the partition plate in the cleaning tank, it is possible to carry out efficient cleaning while sufficiently maintaining the purity of the cleaning liquid. In addition, the cleaning effect can be enhanced, the amount of the cleaning liquid used can be reduced, and the cleaning time can be reduced.

According to the cleaning liquid replacement method of the present invention, 1
When performing a plurality of cleaning processes in one cleaning tank, the effect of replacing a cleaning solution such as a chemical solution or a rinsing solution can be enhanced. Further, the amount of use of a cleaning solution such as a chemical solution or a rinsing solution can be reduced, and the time of the cleaning process, especially the rinsing process, can be reduced.

According to the cleaning apparatus of the present invention, the cleaning of the wafer can be efficiently performed by providing the cleaning tank having the movable partition plate. Further, it is possible to reduce the amount of use of a cleaning liquid such as a chemical solution and a rinsing liquid, and to shorten the cleaning processing time.

According to the cleaning tank of the present invention, since the movable partition plate moves in the tank together with the supply of the cleaning liquid, it is possible to carry out efficient cleaning while maintaining the purity of the supplied cleaning liquid. Further, the cleaning liquid can be replaced, and a plurality of cleaning processes can be performed in one cleaning tank.

[Brief description of the drawings]

FIG. 1 is a top view showing one embodiment of a cleaning tank according to the present invention.

FIG. 2 is a sectional view showing an embodiment of the cleaning tank according to the present invention.

3A to 3D are operation explanatory diagrams of a cleaning process using the cleaning tank of FIG. 2;

FIGS. 4A to 4D are cross-sectional views showing another embodiment of the cleaning tank according to the present invention and operation explanatory views of the cleaning processing (part 1).
It is.

FIGS. 5A to 5F are operation explanatory views (part 2) of a cleaning process in another embodiment of the cleaning tank according to the present invention.

FIGS. 6A to 6D are a cross-sectional view showing still another embodiment of the cleaning tank according to the present invention, and an operation explanatory view of the cleaning process.

FIGS. 7A to 7D are a cross-sectional view showing still another embodiment of the cleaning tank according to the present invention and an operation explanatory view (part 1) of the cleaning process.

FIGS. 8A to 8G are explanatory diagrams (part 2) illustrating the operation of the cleaning process according to still another embodiment of the cleaning tank according to the present invention.

FIG. 9A is a top view showing still another embodiment of the cleaning tank according to the present invention. B is a sectional view thereof.

FIG. 10A is a top view showing still another embodiment of the cleaning tank according to the present invention. B is a sectional view thereof.

FIG. 11 is a sectional view showing still another embodiment of the cleaning tank according to the present invention.

FIG. 12 is a cross-sectional view showing still another embodiment of the cleaning tank according to the present invention.

[Explanation of symbols]

1 ‥‥ cleaning tank, 2 ‥‥ cleaning liquid, 3 ‥‥ cleaning liquid (for example, pure water), 4 ‥‥ tank body, 5 ‥‥ semiconductor wafer, 6 ‥‥ wafer holder, 7 ‥‥ rectifying plate, 8, 8A, 8B {movable partition plate, 26, 27} cleaning liquid (chemical solution)

Claims (15)

[Claims] 1. A cleaning method for immersing a wafer to be cleaned in a cleaning liquid in a cleaning tank for cleaning, wherein a partition plate is moved in the cleaning tank when the cleaning liquid is supplied. 2. The cleaning method according to claim 1, wherein the partition plate is moved upward from below when the overflow of the cleaning liquid is supplied. 3. The cleaning method according to claim 1, wherein the partition plate is moved from top to bottom when the cleaning liquid is supplied in a down flow. 4. A supply amount of the cleaning liquid is L [cm ³ /
Min], the moving speed of the partition plate is V [cm / min], the cross-sectional area of the cleaning tank is S [cm ² ], and the supply amount of the cleaning liquid and the partition plate are set so as to satisfy L ≧ V × S. The moving speed is controlled.
The washing method according to 1. 5. The cleaning method according to claim 1, wherein the cleaning liquid is a rinsing liquid or a chemical liquid. 6. A second cleaning liquid is supplied into the cleaning tank while discharging the first cleaning liquid in a state where the wafer to be cleaned is immersed in the first cleaning liquid in the cleaning tank. A cleaning liquid in the cleaning tank is replaced with the second cleaning liquid by moving a partition plate in the cleaning tank when the cleaning liquid is supplied. 7. The supply amount of the second cleaning liquid is L [cm ³
/ Min], the moving speed of the partition plate is V [cm / min], and the cross-sectional area of the cleaning tank is S [cm ² ], and the supply amount of the second cleaning liquid and the amount of the second cleaning liquid are set to satisfy L ≧ V × S. The cleaning liquid replacement method according to claim 6, wherein the moving speed of the partition plate is controlled. 8. The method according to claim 6, wherein the first and second cleaning liquids are selected from a chemical liquid and a rinsing liquid. 9. A cleaning apparatus, comprising: a cleaning tank provided with one or more movable partition plates that move in the tank when supplying the cleaning liquid. 10. The supply amount of the cleaning liquid is L [cm ³ / cm
Min], the moving speed of the partition plate is V [cm / min], the cross-sectional area of the cleaning tank is S [cm ² ], and the supply amount of the cleaning liquid and the partition plate are set so as to satisfy L ≧ V × S. The cleaning device according to claim 9, wherein the moving speed is controlled. 11. A cleaning tank comprising one or more movable partition plates which move in the tank when supplying a cleaning liquid. 12. The cleaning tank according to claim 11, wherein the cleaning liquid is a rinsing liquid. 13. The cleaning tank according to claim 11, wherein the cleaning liquid is a chemical. 14. The cleaning tank according to claim 11, wherein a plurality of different cleaning liquids are selectively supplied as the cleaning liquid. 15. The supply amount of the cleaning liquid is L [cm ³ / cm
Min], and the moving speed of the movable partition plate is V [cm /
The supply amount of the cleaning liquid and the moving speed of the partition plate are controlled so as to satisfy L ≧ V × S, where S [cm ² ] is a sectional area of the cleaning tank. The washing tank described in 1.