JPH1064871A - Treatment device and treatment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means to prevent bubbles from mixing in a treatment liquid in a treatment tank, in which an object to be treated such as wafer, etc., is immersed in the treatment liquid. SOLUTION: A discharge port 63 of a filling nozzle 62 for filling a treatment liquid into a treatment tank 12 is arranged on the side wall of the tank 12, and the tip end face of the port 63 is made higher as it is apart from the side wall of the tank 12. In addition, when the treatment liquid is discharged through a circulation nozzle 65 on the bottom of the tank 12 so as to circulate the treatment liquid within the tank 12, an air in the nozzle 65 is discharged to the tank 12 through an exhaust circuit before the treatment liquid is discharged from the nozzle 65.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to an apparatus and a method for performing a cleaning process or the like by immersing an object to be processed such as a CD substrate in a processing liquid.

[0002]

2. Description of the Related Art For example, in a semiconductor device manufacturing process, a cleaning system is used to remove contamination such as particles and organic contaminants on the surface of a semiconductor wafer (hereinafter, referred to as "wafer"). Among them, a wet-type cleaning system in which a wafer is immersed in a cleaning liquid in a processing bath for cleaning has an advantage that particles attached to the wafer can be effectively removed.

In order to enable continuous batch processing, this wet-type cleaning system loads, for example, 25 wafers into the apparatus in carrier units, and 50 loaders for two carriers loaded by the loader. Transport means for collectively transporting the wafers, and each processing tank arranged so that 50 wafers transported by the transport means are immersed in the processing liquid, washed, and further dried. Further, an unloader for unloading the wafers cleaned and dried by each processing tank is provided. In each treatment tank of this wet type cleaning system, various treatment liquids are used to alternately perform chemical treatments such as ammonia treatment, hydrofluoric acid treatment, sulfuric acid treatment, hydrochloric acid treatment, and water washing treatment with pure water or the like. Finally, a drying process is performed.

Further, in each processing tank for cleaning the wafer by immersing the wafer in the cleaning liquid, the processing liquid taken out from the upper part of the tank is discharged from a circulation nozzle at the bottom of the processing tank to circulate the processing liquid. As described above, by circulating the processing liquid in the processing tank and constantly circulating the processing liquid on the wafer surface, the efficiency of the cleaning processing is improved and the processing time is shortened.

[0005]

By the way, it is important that air bubbles are not mixed in the processing liquid such as the chemical liquid or the rinsing liquid filled in the processing tank for performing each cleaning of the wafer as described above. It is. If air is mixed into the processing solution in the processing tank as bubbles, the bubbles may adhere to the surface of the wafer, and the portion where such bubbles adhere cannot be cleaned with the processing solution. Would. As a result, problems such as adhesion of particles to the wafer and poor etching uniformity are caused, which causes a reduction in yield in the manufacture of semiconductor devices. However, in particular, when hydrofluoric acid or the like is used as the processing liquid, air bubbles easily enter the processing liquid, which may cause poor cleaning.

[0006] The following two factors are mainly considered as factors that cause bubbles to enter the processing solution. First, when a processing tank is filled with a processing liquid, bubbles generated near the liquid surface of the processing liquid adhere to the inner wall of the processing tank or a boat for supporting a wafer, and the bubbles remain in the processing liquid. It is because of that. That is, before the wafer is carried into the processing tank by the transfer device, the processing tank is pre-filled with the chemical liquid from the filling nozzle, and bubbles are generated near the liquid surface of the processing liquid during the filling. . In addition, the chemical liquid filled in the processing tank is replaced every several batches.For this replacement, bubbles are generated near the liquid level of the processing liquid while a new processing liquid is being filled from the filling nozzle into the processing tank. Occur. The foam may adhere to the inner wall of the processing tank or a boat for supporting the wafer and remain in the processing liquid. The bubbles remaining in the processing liquid in this manner may be separated from the inner walls of the processing tank and floated by vibrations when the wafer is carried into the processing tank, and may adhere to the surface of the wafer during the floating.

Another factor is that when the processing liquid is discharged from the circulation nozzle at the bottom of the processing tank and circulation is started, the air remaining in the circulation nozzle is discharged first. That is, before the processing liquid is filled into the processing tank from the filling nozzle, the circulation nozzle is in a state of being exposed to the air. Will be left in the state. Further, when replacing the processing liquid in the processing tank with a new processing liquid, first, all the old processing liquid in the processing tank is discharged, and then the next new processing liquid is filled in the processing tank. Also in this case, when the old processing liquid is discharged, the circulation nozzle at the bottom of the processing tank is exposed to the air, so that the air enters the circulation nozzle. The air that has entered the circulation nozzle in this way remains in the circulation nozzle even when a new processing solution is filled in the processing tank. Then, when the circulation of the processing liquid is started in a state where the air remains in the circulation nozzle, the air remaining in the circulation nozzle at the beginning of the circulation is discharged first. In this way, the air discharged from the circulation nozzle becomes bubbles and floats in the processing tank, and may adhere to the surface of the wafer during the floating.

An object of the present invention is to provide a means for preventing air bubbles from being mixed into a processing liquid in a processing tank in which a processing object such as a wafer is immersed in the processing liquid for processing. .

[0009]

In order to solve the above-mentioned problems, a first aspect of the present invention provides a processing tank for storing an object to be processed,
In a processing apparatus having a filling nozzle for filling the processing tank with the processing liquid, the discharge port of the filling nozzle is disposed in contact with the side wall of the processing tank, and the height of the tip end surface of the discharge port is set in the processing tank. It is characterized in that it is formed so as to gradually increase as the distance from the side wall increases. In the processing apparatus according to the first aspect, the height of the tip end surface of the discharge port of the filling nozzle may be gradually increased as the distance from the side wall of the processing tank increases.

Further, the invention according to claim 2 includes a processing tank for accommodating the object to be processed and immersing it in the processing liquid, and a circulation nozzle for discharging the processing liquid taken out of the processing tank at the bottom of the processing tank. In the processing apparatus, an exhaust circuit for discharging air in the circulation nozzle out of the processing tank is provided.

Further, according to a third aspect of the present invention, a processing tank for storing an object to be processed is filled with a processing liquid from a filling nozzle, and the processing liquid taken out of the processing tank is discharged from a circulation nozzle at the bottom of the processing tank. In the method for performing processing, the air in the circulation nozzle is discharged out of the processing tank before the processing liquid is discharged from the circulation nozzle.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described based on a cleaning system 1 for cleaning a wafer W as an example of an object to be processed. FIG. 1 is a perspective view of the cleaning system 1.

The cleaning system 1 includes a wafer W before cleaning.
Loading / unloading unit 2 for removing the wafer W from the carrier C, and cleaning a plurality of (for example, 50) wafers W in a batch manner.
The cleaning / drying processing unit 3 for drying and the loading / unloading unit 4 for loading and unloading the wafer W into the carrier C can be roughly classified into three parts.

The loading / unloading section 2 has a loading section 5 for loading and mounting a carrier C capable of storing, for example, 25 wafers W before cleaning, and an unloading section for taking out and aligning the wafers W from the carrier C. 6 are arranged adjacent to each other, and a transfer device 7 for transferring an appropriate number (for example, two) of the carriers C from the loading unit 5 to the unloading unit 6 at a time is provided.

In this embodiment, the cleaning / drying processing section 3 includes a processing tank 11 for cleaning and drying the wafer chuck 36 of the transfer device 30 in order from the loading / unloading section 2 to the loading / unloading section 4. A processing tank 12 for cleaning the wafer W using a cleaning liquid, processing tanks 13 and 14 for rinsing the wafer W cleaned in the processing tank 12, and a wafer W using a cleaning liquid different from the cleaning liquid for the processing tank 12. A processing tank 15 for cleaning, processing tanks 16 and 17 for rinsing the wafer W cleaned in the processing tank 15, a processing tank 18 for cleaning and drying the wafer chuck 38 of the transfer device 32, and respective processing tanks 11 to 17 Of the wafer W cleaned by, for example, IPA
A treatment tank 19 for steam drying with (isopropyl alcohol) or the like is provided.

However, the arrangement and combination of the processing tanks 11 to 19 can be arbitrarily combined depending on the type of cleaning for the wafer W. In some cases, some processing tanks may be omitted, or conversely, other processing tanks may be added. May be. However, the processing tank 19 for drying the wafer W is generally disposed last.

The loading / unloading section 4 includes a loading section 20 having the same configuration as the unloading section 6 of the loading / unloading section 2, an unloading section 21 having the same configuration as the loading section 5, and a transfer having the same configuration as the transfer device 7. An apparatus (not shown) is provided.

On the front side (front side in FIG. 1) of the washing / drying processing section 3, three transporting devices 30, 31, 32 are arranged in order from the loading / unloading section 2 side to the loading / unloading section 4 side. Each of the transporting devices 30, 31, and 32 is configured to be slidable along the guide 33 in the longitudinal direction of the cleaning system 1. Each transport device 30, 31, 3,
2 includes wafer chucks 36, 37, and 38, respectively, and each of the transfer devices 30, 31, and 32 has a predetermined number of wafers W (for example, 50 wafers W for two carriers C) by the wafer chucks 36, 37, and 38. ) Can be grasped collectively.

Of these, the transfer device 30 located on the side of the loading / unloading unit 2 holds the wafer W with the wafer chuck 36 and slides along the guide 33 to move out of the unloading unit 6 of the loading / unloading unit 2. The taken-out wafer W is placed in the processing tanks 12, 1
They are conveyed collectively in the order of 3 and 14. The transfer device 31 located at the center holds the wafer W with the wafer chuck 37 and slides along the guide 33 to move the processing tank 1.
The wafers W are collectively transported in the order of 4, 15, 16, and 17. Further, the transfer device 32 located on the loading / unloading unit 4 side holds the wafer W with the wafer chuck 38 and slides along the guide 33 to collectively transfer the wafers W in the processing tank 17 and the processing tank 19 in this order. The wafer W is further transferred from the processing tank 19 to the unloading section 20 of the loading / unloading section 4 at a time.

Here, since the transfer devices 30, 31, and 32 have the same configuration, the take-out unit 6 and the processing tank 1
Transfer device 30 that transfers wafer W between 2, 13, and 14
For example, as shown in FIG. 2, the wafer chuck 36 of the transfer device 30 includes a pair of left and right holding members 41a and 41b that collectively hold, for example, 50 wafers W as two carriers C. It has.

The gripping members 41a and 41b are symmetrical. The gripping members 41a and 41b are supported by the supporting portion 43 of the transport device 30 by the corresponding rotating shafts 42a and 42b, and can be freely opened and closed. Is configured. The support 43 is moved in the vertical direction (Z direction) by a drive mechanism 44, and the wafer chuck 36 itself is movable in the front-rear direction (Y direction) by a drive mechanism (not shown) built in the support 43. It is configured. The drive mechanism 44 itself is provided on an upper portion of a transport base 45 movable along the longitudinal direction (X direction) of the loading / unloading section 2, the washing / drying processing section 3, and the loading / unloading section 4 shown in FIG. ing. The rotating shafts 42a and 42b are reciprocally rotatable by a driving body (not shown) such as a motor provided in the support portion 43, as shown by a reciprocating rotation arrow θ in FIG. It is configured to be. The support 43 itself is also configured so that its angle can be finely adjusted in a horizontal plane.

On the rotating shafts 42a and 42b, columns 46a,
The upper ends of the columns 46a, 46b, 46b are fixed, and the lower ends of the columns 46a, 46a and the columns 46b, 46b are fixed.
b between the lower ends of the gripping bars 47a, 47b, 4
8a and 48b are passed in parallel. The surface of each gripping rod 47a, 47b, 48a, 48b has a wafer W
For example, fifty grip grooves into which the peripheral portion of the frame is inserted are formed. The gaps (groove pitches) between the holding grooves are arranged at a predetermined distance so as to be equal in the front-rear direction (Y direction). Each of the columns 46a and 46b has a rotating shaft 4
According to the rotation operation of 2a, 42b, the grip bar 47a,
The wafer W is gripped by 47b, 48a, and 48b, and can be transferred to desired positions in the vertical direction (Z direction) and the longitudinal direction (X direction).

The other transfer devices 31 and 32 and the wafer chucks 37 and 38 thereof are also provided in the transfer device 3 described above.
0, has the same configuration as the wafer chuck 36, and holds and conveys, for example, 50 wafers W at a time in the same manner as described above.

At the bottom of each of the processing tanks 12 to 17, a boat 51 serving as a holder for holding the wafer W in each processing tank is installed. Here, the boat 51 installed in the processing tank 12 will be described as a representative with reference to FIG. 2. The boat 51 extends over the lower ends of the supports 52 and 52 ′ vertically installed in the processing tank 13. And three parallel holding rods 53, 54, 55 mounted horizontally. Of these holding rods 53, 54, 55, the center holding rod 54 has the lowest height, and the left and right holding rods 53, 55
Are positioned symmetrically about the holding rod 54 and
It is located at a higher position. These holding rods 53,
On the upper surfaces of the holding rods 54 and 55, for example, 50 holding grooves are formed respectively. The distance between these holding grooves (groove pitch) is also the front-back direction (Y direction).
At a predetermined distance.

The 50 wafers W held together by the wafer chuck 36 are transferred to the transfer device 3
When the lower end of the 50 wafers W is inserted into the holding grooves of the holding rods 53, 54, and 55 of the boat 51, respectively, the transfer device is moved. The support part 43 by the drive mechanism 44 of the 30
Is configured to stop descending. Thus, 5
The zero wafer W is held by the holding rods 53, 54, 55 of the boat 51.
After that, the wafer chuck 36 releases the holding state of the wafer W by the holding members 41a and 41b by the rotation of the rotation shafts 42a and 42b, and the driving mechanism of the transfer device 30 The wafer chuck 36 is retracted above the processing bath 12 as the support 43 is raised by 44.

When the predetermined processing in the processing tank 12 is completed, the wafer chuck 36 is moved down again by the lowering of the support section 43 by the driving mechanism 44 of the transfer device 30.
2, the gripping members 41a, 41b are closed by the rotation of the rotation shafts 42a, 42b, and the 50 wafers W held on the holding rods 53, 54, 55 of the boat 51 are collectively gripped. It is supposed to. Then, the support part 23
Rises, the wafer chuck 36 is placed in the processing tank 1.
2 upward, and 50 wafers W
Are collectively taken out of the processing tank 12 and the next processing tank 13
Transported to

Each of the processing tanks 13 to 1 other than the processing tank 12
7 is also provided with the same boat 51 as described above, and is configured to be able to collectively hold 50 wafers W in each of the processing tanks 13 to 17 as described above. .

Next, the structure of the processing apparatus according to the embodiment of the present invention will be described with reference to FIGS. 3 to 7 by taking as an example a processing tank 12 for performing cleaning using hydrofluoric acid as a cleaning liquid.

As shown in FIG. 3, the processing tank 12 has a box-shaped inner tank 60 having a size large enough to accommodate a wafer W to be processed, and overflows from the upper end of the inner tank 60. And an outer tank 61 for receiving the processing solution to be processed. Although omitted in FIG. 3, the wafer chuck 36 of the transfer device 30 is provided in the inner tank 60 as described above.
The wafer W carried into the processing tank 12 by, for example, 5
A boat 51 that holds zero sheets vertically is arranged.

The upper surface of the inner tank 60 is open, and a filling nozzle 62 for filling hydrofluoric acid as a processing liquid is inserted into the inner tank 60 from the opening. As shown in an enlarged manner in FIG. 4, the discharge port 63 of the filling nozzle 62 is arranged in contact with the inner wall 60 a of the inner tank 60. Further, the filling nozzle 62 is formed on an inclined surface such that the height of the distal end face 63 ′ of the discharge port 63 gradually increases as the distance from the inner wall 60 a of the inner tank 60 increases.

At the bottom of the inner tank 60, a pair of circulating nozzles 65 for discharging the processing liquid taken out of the outer tank 61 again at the bottom of the inner tank 60 and circulating the processing liquid, as described later, are provided.
They are arranged in parallel. As shown in FIG. 5 in an enlarged manner, the circulation nozzle 65 of this embodiment has a hollow cylindrical shape, and a plurality of discharge holes 66 for discharging the processing liquid are formed in the peripheral surface thereof. I have. As shown in FIG. 6, by discharging the processing liquid from the circulation nozzle 65,
In the inner tank 60, the holding rods 53, 54, 5
The processing liquid can be circulated on the surface of the wafer W held on 5. Further, the processing liquid overflowing from above the inner tank 60 due to this circulation is received by the outer tank 61.

As shown in FIG. 7, on the bottom of the inner tank 60,
A drain circuit 71 having a valve 70 is connected. By opening this valve 70, the processing liquid in the inner tank 60 can be discharged from the drain circuit 71 to the outside of the system.

A circuit 72 is connected to the bottom surface of the outer tub 61, and the processing liquid overflowing from above the inner tub 60 and received by the outer tub 61 as described above is drained from the circuit 72 by the drain circuit 73. And the circulation circuit 74 selectively flows. That is, the drain circuit 73 is provided with a valve 75, and by opening this valve 75,
The processing liquid in the outer tank 61 can be discharged out of the system via the circuit 72 and the drain circuit 73. On the other hand, the circulation circuit 74
Pump 80, damper 81, filter 82, temperature controller 8
3 are provided in the order of flow, and the most downstream side of the circulation circuit 74 is connected to one end surface of the circulation nozzle 65 having the cylindrical shape described above. By operating the pump 80, the processing liquid in the outer tank 61 is supplied to the circulation nozzle 65 through the circuit 72 and the circulation circuit 74, thereby circulating the processing liquid in the processing tank 12, and The processing liquid is configured to be able to flow through the surface of the wafer W held in the tank 60. During the flow through the circulation circuit 74, the filter 8
In 2, the processing liquid is purified, and the temperature controller 83 adjusts the temperature of the processing liquid to an appropriate temperature. In particular, when the processing liquid contains hydrogen peroxide solution or the like, since air is accumulated in the filter 82, there is a concern that the filtration efficiency is reduced with a decrease in the filtration area.
An air bleeding circuit 76 for bleeding air collected inside the filter 82 is connected to the upper part of the filter 82. Since there is a possibility that the processing liquid before filtration may enter the air bleeding circuit 76 together with air from inside the filter 82, the air bleeding circuit 76 is configured to return such processing liquid to the outer tank 61 again. ing.

The air in the circulation nozzle 65 is supplied to the processing tank 12 on the other end surface (the end surface opposite to the end surface to which the circulation circuit 74 described above is connected) of the circulation nozzle 65 having a cylindrical shape.
An exhaust circuit 77 for discharging air to the outside is connected. The diameter of the exhaust circuit 77 is formed sufficiently larger than the diameter of the discharge hole 66 formed in the peripheral surface of the circulation nozzle 65 described above. For example, the diameter of the discharge hole 66 is about 1
By forming it to be about mm or less, the air in the circulation nozzle 65 is prevented from forming bubbles and being ejected from the discharge hole 66. On the other hand, by forming the diameter of the exhaust circuit 77 to be about several mm, the air in the circulation nozzle 65 can be exhausted without discharging the air in the circulation nozzle 65 from the discharge hole 66.
7. A valve 78 is provided in the middle of the exhaust circuit 77, and in the example shown in the figure, by opening the tip of the exhaust circuit 77 above the outer tank 61, the processing liquid is supplied from the circulation nozzle 65 together with air. When entering, the processing liquid is returned to the outer tank 61 again.

Now, the processing steps of the wafer W in the cleaning system 1 configured as described above will be described.
By an appropriate transfer means such as a transfer robot (not shown),
The carrier C is placed on the loading section 5 of the loading / unloading section 2.
A wafer W that has not been cleaned yet is contained in the carrier C.
For example, a predetermined number such as 25 sheets is loaded. And
The carrier C placed on the placement unit 5 is transferred to the alignment unit 6 by the transfer device 7, and is aligned with the alignment unit 6 in a state where, for example, 50 wafers W for two carriers C are aligned with the orientation flat. Wait for the subsequent cleaning process.

The wafers W aligned in the unloading section 6 of the loading / unloading section 2 are then transferred to the cleaning / drying processing section 3
Are cleaned and dried in the processing tank 11, and are collectively gripped by the wafer chuck 36 of the transfer device 30 while maintaining the aligned state, and transferred to each of the processing units 12, 13, and 14, where the wafer W is subjected to the cleaning liquid. It is immersed in and sequentially washed.

Here, the cleaning step will be described by taking as an example the processing tank 12 for performing cleaning using hydrofluoric acid as a cleaning liquid.
Before the wafer W is transferred by the wafer chuck 36 of the transfer device 30, the inner tank 60 of the processing tank 12 is filled with hydrofluoric acid as a processing liquid from the filling nozzle 62. At the time of filling, as described above, the discharge port 63 of the filling nozzle 62 is arranged in contact with the inner side wall 60a of the inner tank 60, and the discharge port 63 of the filling nozzle 62 is formed.
Is formed on the inclined surface so that the height of the front end surface 63 ′ gradually increases as the distance from the inner wall 60 a of the inner tank 60 increases, so that the processing liquid discharged from the filling nozzle 62 is It flows smoothly along 60a, and generation of bubbles is suppressed. When the processing liquid overflows from the inner tank 60 to fill the outer tank 61 with the processing liquid by continuously performing the filling, the filling of the processing liquid from the filling nozzle 62 ends once. . Then, the 50 wafers W held by the wafer chuck 36 of the transfer device 30 described with reference to FIG.
Is carried into the inner tank 60. Thus, 50 wafers W
Is transferred to the boat 51 in the inner tank 60 in an aligned state, the wafer chuck 36 releases the gripping state of the wafer W, and the wafer chuck 36 retreats above the processing tank 12.

When the transfer of the wafer W is completed, the operation of the pump 80 described with reference to FIG. 7 starts. As a result, the processing liquid in the outer tank 61 starts to be supplied to the circulation nozzle 65 via the circuit 72 and the circulation circuit 74.
At the time when air is still remaining in the circulation nozzle 65 at the start of supplying the processing liquid to the circulation nozzle 65, the valve 78 of the exhaust circuit 77 described with reference to FIG. 7 is opened, and the exhaust circuit 77 is opened to atmospheric pressure. deep. As described above, the diameter of the exhaust circuit 77 is sufficiently larger than the diameter of the discharge hole 66 on the peripheral surface of the circulation nozzle 65. For example, while the diameter of the discharge hole 66 is about 1 mm or less, the exhaust circuit 77 Since the diameter of 77 is about several mm, when the processing liquid is supplied to the circulation nozzle 65, the air remaining in the circulation nozzle 65 does not blow out from the discharge hole 66 as bubbles. , Flows smoothly into the exhaust circuit 77 which is open to the atmospheric pressure. Therefore, it is possible to prevent the air from being emitted from the discharge hole 66 as bubbles.

After the air remaining in the circulation nozzle 65 is sufficiently discharged from the exhaust circuit 77 before the processing liquid is discharged from the circulation nozzle 65, the valve 78 is closed and the discharge hole 66 on the peripheral surface of the circulation nozzle 65 is discharged. , The processing liquid is circulated and supplied to the surface of the wafer W held on the boat 51 in the inner tank 60. Then, the processing liquid overflowing from above the inner tank 60 due to this circulation is received by the outer tank 61, and the processing liquid is again supplied to the circulation nozzle 65 via the circuit 72 and the circulation circuit 74. Since the tip of the exhaust circuit 77 is opened above the outer tank 61, even if some processing liquid enters the exhaust circuit 77 from the circulation nozzle 65, the processing liquid can be returned to the outer tank 61. Since it is possible, the air remaining in the circulation nozzle 65 is sufficiently expelled to the exhaust circuit 77, and then the valve 78 is closed to start circulation of the processing liquid.

When the cleaning in the processing tank 12 is completed, for example, after a predetermined time has elapsed, the wafer chuck 36 of the transfer device 30 is moved to the inner tank 60 of the processing tank 12.
And the 50 wafers W held on the boat 51 are collectively gripped and lifted. Then, 50 wafers W are collectively taken out of the inner tank 60 of the processing tank 12, and
It is transported to the next processing tank 13. 5 carried into processing tank 13
The zero wafer W is similarly rinsed with pure water circulated and supplied from the bottom of the tank. Further, the wafer W that has been rinsed in the processing tank 13 is similarly transferred to the next processing tank 14 by the wafer chuck 36 of the transfer device 30 and rinsed again. In this way, the wafer W that has been cleaned with hydrofluoric acid waits for cleaning with another processing liquid in the subsequent processing tanks 15 to 17 on the boat at the bottom of the processing tank 14. Then, the next wafer transfer device 31 takes out the wafer W waiting on the boat at the bottom of the processing tank 14,
It is conveyed to each processing tank 14-17. After a predetermined cleaning process according to the same process as above, the wafer W is placed in the processing tank 17.
The drying process in the subsequent processing tank 19 is on standby on the bottom boat. Hereinafter, after performing the steam drying process by the IPA in the drying process tank 19, the wafer W is carried out of the apparatus by the carrier C via the loading / unloading unit 4.

On the other hand, in order to perform the above-mentioned cleaning using the processing liquid well, it is necessary that the processing liquid in each of the processing tanks 12 to 17 is always fresh. Therefore, an operation of replacing the processing liquid in each of the processing tanks 12 to 17 with a new processing liquid every several batches is performed. This exchange work will be described for the processing tank 12. First, the valve 70 described with reference to FIG. 7 is opened, and the processing liquid in the inner tank 60 is discharged from the drain circuit 71 to the outside of the system. When the valve 75 is opened, the processing liquid in the outer tank 61 is discharged out of the system via the circuit 72 and the drain circuit 73.

After discharging the old processing liquid from the inner tank 60 and the outer tank 61 of the processing tank 12 in this manner, the valve 70,
Close 75. Then, the new processing liquid is supplied to the filling nozzle 62.
Is filled into the inner tank 60. At the time of this filling, the processing liquid discharged from the filling nozzle 62 is also supplied to the inner tank 6.
By smoothly flowing along the inner wall 60a of 0, generation of bubbles can be suppressed. Then, when the processing liquid overflows from the inner tank 60 to fill the outer tank 61 with the processing liquid, the supply of the processing liquid from the filling nozzle 62 is stopped, and the loading of the next wafer W is awaited. State.

When the next wafer W is loaded,
The operation of the pump 80 described with reference to FIG.
The processing liquid in the outer tank 61 starts to be supplied to the circulation nozzle 65 through the circuit 72 and the circulation circuit 74. In this case, similarly, before the processing liquid is discharged from the circulation nozzle 65, the exhaust circuit 77 described in FIG. Opening the valve 78 of the circulation nozzle 6
The air remaining in 5 is discharged out of the processing tank. Then, the air remaining in the circulation nozzle 65 is discharged into the exhaust circuit 77.
After sufficient discharge from the circulation nozzle 6
The discharge of the processing liquid from the discharge holes 66 on the fifth circumferential surface is started.

Thus, the processing tank 12
By preventing air from being mixed into the processing liquid in the inner tank 60, cleaning defects can be reduced, and the yield in the manufacture of semiconductor devices can be improved. In addition, although the main description was given of the processing tank 12 for performing cleaning using hydrofluoric acid as a processing liquid, the present invention provides:
For example, the present invention can be applied to cleaning tanks 13 to 17 for performing other cleaning processing and the like, and a method and an apparatus for performing processing using other various processing liquids.

[0045]

EXAMPLE Next, in order to confirm the effect of the present invention, the processing tank 1 was used.
An experiment was conducted on a filling nozzle for filling the inner tank 60 with the processing liquid. The results are shown below.

8 to 10 are comparative examples. That is, the filling nozzle 90 of FIG.
The second inner tank 60 was disposed so as to discharge at the opening. The filling nozzle 91 shown in FIG. 9 is disposed so as to perform discharge at a position slightly away from the inner wall surface of the inner tank 60 of the processing tank 12. The tip surface of the discharge port of the filling nozzle 91 has a planar shape. The filling nozzle 92 shown in FIG. 10 has a tip bent at a right angle to the inside of the inner tank 60 of the processing tank 12 so as to perform discharge toward the inside of the inner tank 60.

FIG. 11 shows an embodiment of the present invention. The discharge port of the filling nozzle 93 is the processing tank 1
2 was arranged so as to be in contact with the side wall of the inner tank 60, and the height of the tip end surface of the discharge port was formed so as to gradually increase as the distance from the side wall of the inner tank 60 increased.

In any of the cases of FIGS.
The experiment was conducted with the boat 51 installed in the inner tank 60 of No. 2. Further, as a processing liquid to be filled into the inner tank 60 of the processing tank 12,
Using a 49% hydrofluoric acid solution in a volume ratio of 1:19 dilute hydrofluoric acid solution, when the treatment liquid is filled by each of the filling nozzles 90 to 93, bubbles adhering to the inner tank 60 are visually observed. did. The filling flow rate is 8 liter / min.

As a result, when the processing liquid is filled from the filling nozzle 90 shown in FIG.
Many bubbles adhered to the side. When the processing liquid was filled from the filling nozzle 91 shown in FIG. 9, almost no bubbles adhered to the wall surface of the inner tank 60, but some bubbles adhered to the side surface of the boat 51. When the processing liquid is filled from the filling nozzle 91 shown in FIG.
Almost no bubbles adhered to the wall.
Many bubbles adhered to the side.

On the other hand, when the processing liquid was filled from the filling nozzle 93 in the embodiment shown in FIG. 11, almost no bubbles adhered to either the wall surface of the inner tank 60 or the side surface of the boat 51.

[0051]

According to the present invention, it is possible to greatly reduce processing defects such as cleaning processing by preventing air from being mixed into the processing liquid. Therefore, according to the present invention, the processing of the object to be processed can be performed smoothly, and for example, the yield in the manufacture of semiconductor devices can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a cleaning system 1. FIG.

FIG. 2 is an enlarged perspective view showing an example of a transport device.

FIG. 3 is a perspective view schematically showing an example of a processing tank.

FIG. 4 is an enlarged vertical sectional view of a filling nozzle.

FIG. 5 is a perspective view of a circulation nozzle.

FIG. 6 is a longitudinal sectional view of a processing tank.

FIG. 7 is a piping diagram of a processing tank.

FIG. 8 is an explanatory diagram of a comparative example of a filling nozzle.

FIG. 9 is an explanatory diagram of a comparative example of a filling nozzle.

FIG. 10 is an explanatory diagram of a comparative example of a filling nozzle.

FIG. 11 is an explanatory view of an embodiment of a filling nozzle.

[Explanation of symbols]

 W Wafer 12 Processing tank 60 Inner tank 61 Outer tank 62 Filling nozzle 63 Discharge port 65 Circulation nozzle 77 Exhaust circuit

Claims (3)

[Claims] 1. A processing apparatus comprising: a processing tank for storing an object to be processed; and a filling nozzle for filling the processing tank with a processing liquid, wherein a discharge port of the filling nozzle is arranged in contact with a side wall of the processing tank. A processing apparatus, wherein the height of the tip end surface of the discharge port is gradually increased as the distance from the side wall of the processing tank increases. 2. A processing apparatus comprising: a processing tank for storing an object to be processed and immersed in a processing liquid; and a circulation nozzle for discharging a processing liquid taken out of the processing tank at a bottom of the processing tank. A processing apparatus provided with an exhaust circuit for discharging air inside the processing tank to the outside of the processing tank. 3. A method for performing processing by filling a processing tank containing an object to be processed with a processing liquid from a filling nozzle and discharging the processing liquid taken out of the processing tank from a circulation nozzle at the bottom of the processing tank. A processing method, wherein air in the circulation nozzle is discharged out of the processing tank before the processing liquid is discharged from the circulation nozzle.