JPH04336429A - Cleaning apparatus - Google Patents

Abstract

PURPOSE:To prevent corrosion of a transport means for transporting processing objects and improve the effect of cleaning in a cleaning apparatus for cleaning processing objects with a processing solution. CONSTITUTION:A transport means 4 is formed by a multi-joint transport arm comprising a plurality of arm bodies 5 which are rotatably coupled with each other. An arm body 5 is formed by a hollow type coupling axis 7 for coupling the arm bodies 5 and a cover 8 for wrapping the coupling axis 7 while leaving an unwrapped space 8a connected with the hollow part 7a of the coupling axis 7. The space 8a within the cover of the arm body 5 is maintained under the pressurized condition by connecting a pressurizing means 10 to the hollow part 7a of the coupling axis 7 in order to prevent entry of chemicals staining the transport arm 4 and also prevent corrosion of the transport arm 4.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus, and more specifically, a cleaning chamber for cleaning objects to be processed, such as semiconductor wafers, with a processing liquid, and a cleaning apparatus located adjacent to the cleaning chamber. The present invention relates to a cleaning apparatus that includes a processing object transport chamber, and a transport means disposed within the processing object transport chamber for carrying the processing object into and out of the cleaning processing chamber.

0002

2. Description of the Related Art Generally, in semiconductor manufacturing processes, cleaning equipment is used to remove chemicals, impurities, etc. adhering to the surface of semiconductor wafers. This cleaning equipment performs, for example, ammonia treatment, water washing treatment, etc. on semiconductor wafers.
The surface of the semiconductor wafer is cleaned by sequentially performing various treatments such as hydrofluoric acid treatment.

Therefore, conventional cleaning equipment has a plurality of cleaning processing chambers in which processing tanks such as an ammonia processing tank, a water washing processing tank, a hydrofluoric acid processing tank, etc. are arranged, and a semiconductor wafer as an object to be processed is transferred to a transport means. Place and hold the container at the
It was being carried out. In this case, a multi-joint transfer arm in which a plurality of arm bodies are rotatably connected to each other is used as the transfer means. This transfer arm is disposed in a chamber adjacent to the processing chamber, and carries in and out semiconductor wafers through an opening provided in the chamber for carrying in and out semiconductor wafers.

0004

[Problems to be Solved by the Invention] However, in conventional cleaning equipment of this type, since the transfer arm carries semiconductor wafers into and out of cleaning processing chambers with different atmospheres, the chemical solution handled in the pretreatment is transferred to the transfer arm. There is a problem in that this chemical solution sometimes intrudes into the drive section side of the transfer arm, and as a result, the drive section side of the transfer arm corrodes. Further, if chemicals or other impurities adhere to the transfer arm, the atmosphere in the room in which the transfer arm is disposed is disturbed, contaminating the semiconductor wafers, and reducing the product yield of the semiconductor wafers.

The present invention was made in view of the above circumstances, and provides a cleaning device that prevents corrosion of the drive section of the transfer arm and maintains the same clean atmosphere in the room in which the transfer arm is disposed. The purpose is to provide the following.

[0006]

[Means for Solving the Problems] In order to achieve the above object, a first cleaning device of the present invention includes a cleaning chamber for cleaning an object to be treated with a treatment liquid, and a cleaning chamber located adjacent to the cleaning chamber. The above-mentioned method is based on the assumption that the cleaning apparatus is equipped with a processing object transport chamber, and a transport means arranged in the processing object transport chamber and transporting the processing object into and out of the cleaning processing chamber. The conveyance means is formed by a multi-joint conveyance arm including a plurality of arm bodies rotatably connected to each other, and the arm body is formed of a hollow connecting shaft connecting adjacent arm bodies, and a hollow connecting shaft connecting adjacent arm bodies, and a hollow connecting shaft connecting adjacent arm bodies. and a cover that surrounds the connecting shaft leaving a space communicating with the hollow part, and a pressurizing means is connected to the hollow part of the connecting shaft to maintain the inner space of the cover of the arm body in a pressurized state. It is something to do.

[0007] A second cleaning device of the present invention is the cleaning device of the first invention, in which an air supply port is provided in the upper part of the object transfer chamber, and a filter member is provided to the air supply port. An air supply means is connected, an exhaust/drain port is provided at the bottom of the object transfer chamber, and a suction means is connected to the exhaust/drain port, so that the object transfer chamber is moved from the top to the bottom. A rectifying means is arranged in a direction perpendicular to the clean air flow flowing toward the air.

[0008] In this invention, it is preferable that the connecting portions of the arm bodies are connected via a sealing mechanism, and
It is preferable that the cover of the arm body be formed of a corrosion-resistant member. In this case, a member made of vinyl chloride, for example, can be used as the corrosion-resistant member.

The above-mentioned pressurizing means maintains the inner space of the cover of the arm body in a pressurized state, and can be achieved, for example, by filling the inner space of the cover with air or nitrogen (N2) gas.

The object-to-be-processed transfer chamber may have any structure as long as it has a space for arranging a transfer arm and an opening in the side wall for carrying in and out the object to be processed. It can be formed of a cylindrical container made of a corrosion-resistant member having a bottom portion and a bottom portion integrally formed. In this case, a member made of vinyl chloride, for example, can be used as the corrosion-resistant member.

[0011] The rectifying means may be of any type as long as it is disposed in a direction perpendicular to the clean air flow flowing from the upper part to the lower part of the processing object transfer chamber, but it is preferably a corrosion-resistant member. It is preferable to use a perforated plate formed by. In this case, a member made of vinyl chloride, for example, can be used as the corrosion-resistant member.

0012

[Operation] According to the cleaning device of the present invention configured as described above, there is a hollow connecting shaft that connects adjacent arm bodies, and a space that surrounds the connecting shaft leaving a space that communicates with the hollow part of the connecting shaft. By connecting the pressurizing means to the hollow part of the connecting shaft and maintaining the space inside the cover of the arm body in a pressurized state, the transport arm for the chemical solution that adheres to the transport arm is constructed. In addition to preventing intrusion into the drive unit,
Corrosion of the transport arm can be prevented.

[0013] In addition, the purified clean air is allowed to flow down from the upper part to the lower part of the processing object transfer chamber, and is also rectified by the rectifying means and discharged from the exhaust/drain port at the bottom. A clean atmosphere can be maintained without the atmosphere inside the processing object transfer chamber being disturbed by the chemical solution or other impurities attached to the processing object.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic sectional view of a part of the cleaning device of the present invention, and FIG. 2 is an enlarged sectional view of the main part of FIG.

The cleaning apparatus of the present invention includes a cleaning processing chamber 2 for cleaning a semiconductor wafer 1 as an object to be processed by immersing it in a processing liquid contained in a cleaning tank (not shown), and a cleaning processing chamber 2 adjacent to the cleaning processing chamber 2. a processing object transfer chamber 3 disposed at a position where
A transfer arm 4 is provided in the object transfer chamber 3 and is a transfer means for loading and unloading the semiconductor wafer 1 into and out of the cleaning processing chamber 2.

The transfer arm 4 has a multi-jointed structure formed by a plurality of arm bodies 5 (specifically, 5a to 5d) that are rotatably connected to each other, and the uppermost arm body 5
A forked fork 6 for mounting and holding the semiconductor wafer 1 is provided protruding from d. Each arm body 5 also includes a hollow connecting shaft 7 that connects adjacent arm bodies 5, and a vinyl chloride-made connecting shaft 7 that surrounds the connecting shaft 7 leaving a space 8a that communicates with the hollow portion 7a of this connecting shaft 7. It is composed of a cover 8. In addition, a hollow portion 7a is provided in the connecting shaft 7 of the arm body 5a at the lowest stage.
A ventilation hole 7b is provided which communicates with the
A N2 gas tank 10, which is pressurization means, is connected to b via a supply pipe 9. Therefore, N2 gas flows from the N2 gas tank 10 through the supply pipe 9 into the hollow part 7a of the connecting shaft 7, and fills the space 8a of the adjacent arm body 5 from the hollow part, so that the space 8a is pressurized. This makes it possible to prevent chemical liquids and the like adhering to the transport arm 4 from entering the drive section of the transport arm 4.

In this case, a sealing mechanism is provided at the connecting portions of the adjacent arm bodies 5a to 5d. Here, a sealing mechanism between the lowermost arm body 5a and the upper arm body 5b will be described as a representative example. That is, as shown in FIG. 2, the cylindrical fixed shaft 1 is attached to the cover 8 of the lowermost arm body 5a and protrudes into the cover 8 of the upper arm body 5b.
A sleeve 11b made of fluororesin is fitted onto the outer peripheral surface of the arm 1a, and an O-ring 11c is interposed between the sleeve 11b and the cover 8 of the lowermost arm body 5a facing the arm 5a.
In addition, the cover 8 and sleeve 11b of the upper arm body 5b
By interposing a synthetic rubber sealing member 11d between them, the space 8a of the object transfer chamber 3 and the drive section of the transfer arm 4 can be sealed. Further, the cover 8 of the lowermost arm body 5a is provided with an O-ring groove 11f in which an O-ring 11e is disposed on the surface that contacts the bottom 3d of the container 3. Furthermore, an O-ring 11g is interposed at the joint between the arm body 5b and the cover 8 to maintain airtightness. A drive shaft 13, on which the connecting shaft 7 is loosely fitted, is rotatably supported on the inner side of the cylindrical fixed shaft 11a via a bearing 12.

On the other hand, the processing object transfer chamber 3 is a rectangular cylindrical chloride chamber having an opening 3b for loading and unloading the semiconductor wafer 1 and the transfer arm 4 on a side wall 3a facing the adjacent cleaning chamber 2. It is formed of a vinyl container, and this container 3
An upper rectifying member 14 formed of a porous plate made of vinyl chloride and a filtering means H are provided in the opening 3c provided in the ceiling surface of the
An air supply passage is connected through an EPA (or ULPA) filter 15, and an air supply fan 16 serving as an air supply means is disposed in this air supply passage to supply purified clean air A into the container 3. It is now being supplied. A shutter 17 is disposed in the opening 3b so as to be openable and closable, and an air outlet (not shown) is provided in the upper part of the opening 3b to form an air curtain.

Furthermore, the bottom 3d of the container 3 has a stepped shape where the outer circumferential side is lower than the inner circumferential side, and exhaust/drain ports 3f are provided at two locations in the circumferential groove 3e on the outer circumferential side. These exhaust/
A suction means (not shown) is connected to the drain port 3f via a discharge pipe 18, and a gas-liquid separator 1 is connected in the middle of the discharge pipe 18.
9 are arranged. Further, a perforated plate 20 made of vinyl chloride serving as a flow straightening means is installed horizontally near the upper part of the bottom 3d of the container 3, and this perforated plate 20 regulates the laminar flow state of the downflow of clean air flowing into the container 3. It also prevents the exhaust gas, drained liquid, etc. accumulated at the bottom 3d of the container 3 from rising upward.

A cleaning/drying nozzle 40 is provided at the top of the container 3 for cleaning and drying the chemical solution, impurities, etc. adhering to the fork 6 of the transport arm 4. This cleaning/drying nozzle 40 can be switched between a cleaning/drying position and a side standby position by a rotary actuator (not shown), and pure water for cleaning and N2 gas for drying are supplied from a supply means (not shown). It looks like this.

With the above configuration, the clean air A supplied into the container 3 from the upper part of the container 3 is made into a laminar flow state by the perforated plate 20 and is discharged from the exhaust/drain port 3f. A clean atmosphere is maintained inside the container 3. That is, the atmosphere inside the container 3 may be disturbed due to scattering of chemical liquids, impurities, etc. attached to the transfer arm 4 into the container 3, or leakage of N2 gas filled to pressurize the inside of the cover 8 of the transfer arm 4. It is possible to prevent this from happening. Therefore, the semiconductor wafer 1 can be transported in a clean state.

Next, the overall structure of the cleaning device is shown in FIG.
Explain with reference to.

FIG. 3 shows three cleaning processing units 21, 2.
2 and 23, a loader 24 is connected to the washing processing unit 21 on the carry-in side, an unloader 25 is connected to the washing processing unit 23 on the carrying-out side, and the washing processing unit 21 , 22 and between the cleaning processing units 22 and 23, an underwater loader 26 that constitutes a part of a processing chamber included in any of the three units is disposed.

In the washing processing unit 21 on the carry-in side, a container 3 with a transport arm 4 arranged therein is located at the center, and an ammonia processing chamber 27 and a water washing processing chamber are located on the left side of the container 3 and in front of the loader 24, respectively. A chamber 28 is provided.

In the central cleaning processing unit 22, a container 3 with a transport arm 4 arranged therein is located at the center, underwater loaders 26 are arranged on both left and right sides around the container 3, and a hydrofluoric acid processing chamber is located in the front and back positions between them. 29, a water washing overflow processing chamber 30 is provided.

[0027] Furthermore, the cleaning unit 23 on the unloading side is
A container 3 with a transport arm 4 disposed in the center is located, a water final rinse processing chamber 31 is provided around the container 3 on the front side of the unloader 25, and a drying processing chamber 32 is provided to the right of the container 3. It will be arranged.

In the cleaning processing apparatus configured as described above, when two carriers 33 each carrying 25 semiconductor wafers 1 are transported to the loader 24, the orientation flat alignment mechanism 34 operates to align the carriers. The semiconductor wafers 1 within 33 are aligned. Next, the push-up rods (not shown) operate upward to take out only the semiconductor wafers 1 upward while leaving the carrier 33 intact, and then the push-up rods move toward each other and pick up the 50 semiconductor wafers 1 at equal intervals. position.

Next, the transport arm 4 is operated and horizontally rotated, and extends toward the loader 24, so that the fork 6 at the tip is positioned below the push-up rod. Then, the push-up rod is lowered, and the semiconductor wafer 1 is positioned on the fork 6.

Next, with the semiconductor wafer 1 placed on the fork 6, the transfer arm 4 horizontally rotates and expands and contracts to transfer the semiconductor wafer 1 from the opening 3b of the ammonia treatment chamber 27 to the ammonia treatment chamber 27. It is inserted into the dedicated boat 27b of the processing tank 27a. And transport arm 4
When the ammonia treatment chamber 27 exits, the shutter 17 of the opening 3b closes and air is blown out from the air outlet at the top of the opening to form an air curtain, and the atmosphere inside the ammonia treatment chamber 27 is changed to the outside. It is designed to reliably prevent leakage. In this state, the semiconductor wafer 1 in the ammonia treatment chamber 27 is cleaned.

On the other hand, when the fork 6 of the transfer arm 4 returns from the ammonia treatment chamber 27 into the container 3, the rotary actuator 13 is activated to close the cleaning/drying nozzle 40.
is moved to a position above the fork 6, and cleaning and drying are performed. At this time, since the cover inner space 8a of the transfer arm 4 is filled with N2 gas, the chemical solution and the like will not enter the drive section side of the transfer arm 4, and there is no fear that the transfer arm 4 will corrode. In addition, inside the container 3, the perforated plates 14 and 20 form a downflow in which the clean air supplied from the top is discharged from the exhaust/drain port 3f at the bottom in a laminar flow state, so the atmosphere inside the container 3 is always maintained. Maintained in a clean condition.

After the cleaning in the ammonia treatment chamber 27 is completed, the semiconductor wafer 1 on the boat 27b is placed and positioned on the fork 6 of the transfer arm 4 by an operation in the opposite direction to that described above. The semiconductor wafer 1 is taken out of the ammonia treatment chamber 27 and carried into the next water washing treatment chamber 28 . Then, the fork 6 of the transfer arm 4 that has returned from the water washing processing chamber 28 is cleaned and dried by the cleaning/drying nozzle 40 in the same manner as described above, and the next 50 new semiconductor wafers 1 are transferred. It becomes possible. Therefore, the transfer arm 4 is cleaned and dried while waiting after the transfer of the semiconductor wafer 1, and the intrusion of chemicals and the like into the drive unit side is prevented, so that the cleaning process of the semiconductor wafer 1 can be carried out continuously and efficiently. It can be carried out. In addition, since the transfer arm 4 is disposed inside the container 3 in an atmosphere that is purified by the downflow of clean air, it is possible to prevent the chemical solution adhering to the transfer arm 4, the waste liquid used for cleaning, and even the space inside the cover. The atmosphere can be safely discharged without disturbing the atmosphere in the unlikely event that the N2 gas filled in 8a leaks.

The semiconductor wafer 1 that has been cleaned by the cleaning unit 21 on the loading side is transferred to the cleaning unit 22 at the central location by an underwater loader 26 between the cleaning unit 21 at the loading side and the central cleaning unit 22. It is transported in the same manner as described above by the transport arm 4 disposed inside the container 3 of the central cleaning processing unit 22. Then, the semiconductor wafer 1 is sequentially subjected to a cleaning process in a hydrofluoric acid treatment chamber 29 and a water washing overflow treatment in an overflow treatment chamber 30. Also in the cleaning process by this intermediate cleaning unit, the fork 6 of the rotary transfer arm waiting in the container 3 is cleaned and dried by the cleaning/drying nozzle 40 in the same manner as described above, and is placed in a clean atmosphere. .

The semiconductor wafer 1 that has been cleaned in the central cleaning unit 22 is transferred to the unloading side by the underwater loader 26 between the central cleaning unit 22 and the unloading cleaning unit 23. It is transported to the cleaning processing unit 23. Then, it is transported by the transport arm 4 of the cleaning processing unit 23 on the discharge side in the same manner as described above, and after final rinsing is performed, a drying process is performed. In the cleaning by the cleaning processing unit 23 on the carry-out side, the fork 6 of the transfer arm 4 is connected to the cleaning/drying nozzle 4 in the same way as described above.
The semiconductor wafer 1 is cleaned and dried by the wafer 0, and the semiconductor wafer 1 is transported in a constantly cleaned state.

The semiconductor wafer 1 that has been cleaned in the cleaning unit 23 on the unloading side is transferred to the unloader 25.
The unloader 25 divides the semiconductor wafer 1 into 25 wafers each, aligns the orientation flat, and carries out the wafers placed on two carriers.

In the above embodiments, the cleaning apparatus of the present invention was explained as a cleaning apparatus for semiconductor wafers 1, but it is not necessarily limited to cleaning apparatuses for semiconductor wafers 1, and may be used for other cleaning apparatuses such as LCD glass substrates. Of course, it can be applied to

[0037]

As explained above, since the cleaning device of the present invention is constructed as described above, the following effects can be obtained.

1) According to the cleaning device according to claim 1, there is provided a hollow connecting shaft connecting adjacent arm bodies, and a cover surrounding the connecting shaft leaving a space communicating with the hollow portion of the connecting shaft. Since the arm body is configured with a pressurizing means connected to the hollow part of the connecting shaft and the space inside the cover of the arm body is maintained in a pressurized state, the chemical solution adhering to the transport arm is prevented from entering the transport arm drive part. It is possible to prevent invasion and corrosion of the transfer arm, and to improve cleaning efficiency. Also,
It is possible to extend the life of the device and improve its reliability.

2) According to the cleaning device according to claim 2, the cleaned air flows down from the upper part to the lower part of the processing object transfer chamber, and is rectified by the rectifying means to be exhausted and exhausted at the bottom. Since it can be discharged from the liquid port,
A clean atmosphere can be maintained without disturbing the atmosphere in the processing object transfer chamber due to chemicals and other impurities attached to the transfer arm, and in addition to 1) above, there is a reduction in the yield of processing objects. can be prevented.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing a part of a cleaning device of the present invention.

FIG. 2 is an enlarged sectional view of the main part of FIG. 1;

FIG. 3 is a sectional view showing the overall structure of the cleaning device.

[Explanation of symbols]

1 Semiconductor wafer (processed object) 2 Cleaning processing chamber 3 Container (processed object transfer chamber) 3c Air supply port 3f Exhaust/drainage port 4 Transfer arm (transport means) 5 (5a to 5d) Arm body 7 Connection shaft 7a Hollow part 8 Cover 8a Space 9 Supply pipe 10 N2 gas tank (pressurization applying means) 15 H
EPA (or ULPA) filter 16 Air supply fan (
Air supply means) 18 Discharge pipe 20 Perforated plate (straightening means)

Claims (2)

[Claims] 1. A cleaning processing chamber for cleaning a processing object with a processing liquid, a processing object transporting chamber disposed adjacent to the washing processing chamber, and a processing object transporting chamber disposed within the processing object transporting chamber. A cleaning apparatus comprising a transport means for carrying the object to be processed into and out of the cleaning processing chamber, wherein the transport means is a multi-joint transport arm comprising a plurality of arm bodies rotatably connected to each other. form the arm body,
It is composed of a hollow connecting shaft that connects adjacent arm bodies, and a cover that surrounds the connecting shaft leaving a space communicating with the hollow part of the connecting shaft, and a means for applying pressure to the hollow part of the connecting shaft. A cleaning device characterized in that the space inside the cover of the arm body is maintained in a pressurized state by being connected to the arm body. 2. The cleaning apparatus according to claim 1, wherein an air supply port is provided in the upper part of the object transfer chamber, and an air supply means is connected to the air supply port via a filter member.
An exhaust/drain port is provided at the bottom of the object transfer chamber, and a suction means is connected to the exhaust/drain port, so that clean air flows from the top to the bottom in the object transfer chamber. A cleaning device characterized by having a rectifying means arranged in a direction perpendicular to the direction.