JPS6032717B2 - cleaning equipment - Google Patents

Description

[Detailed description of the invention] The present invention relates to a cleaning device for tubular objects.

In the production of semiconductor devices, integrated circuits, etc., a thin semiconductor board (wafer) is placed in a furnace tube made of a quartz tube that is maintained in a heated state, and a prescribed reaction gas is flowed into the furnace tube to coat the surface of the wafer. There are operations to form impurities and to diffuse impurities.

In this operation, various products are generated in the reactor core tube (also simply referred to as a tube) due to reactions of reaction gases, and these products adhere to undesirable tube walls other than the wafer. For this reason, this adhesion layer becomes a lump and falls from the tube wall and adheres to the wafer surface, causing abnormal growth of the film on the wafer surface. Further, impurities contained in the deposited layer re-evaporate into the tube and diffuse again into the surface layer of the wafer (so-called autodoping), resulting in non-uniform diffusion concentration. Therefore, the furnace core tube is removed from the diffusion furnace (heat treatment equipment) every certain number of times, and cleaning work is performed to remove the coating that adheres to the inner wall of the tube.This cleaning work is performed as shown in Figures 1 and 2. It is proposed to use a cleaning device with a similar structure.

That is, this cleaning device has first to third cleaning tanks in parallel.
A cleaning tank 3 is provided, and the first cleaning tank 1 contains an etching solution for dissolving the film attached to the inner wall of the reactor core tube 4, for example, an etching solution mainly containing acid in the case of silicon or silicon compounds. The second cleaning tank 2 is filled with pure water and is sequentially supplied with pure water. Further, a plurality of rollers 5 whose rotation is controlled are disposed below the third cleaning tank 3, and the reactor core tube 4 cleaned in the second cleaning tank 2 is placed on these rollers 5 and rotated. There is. Further, an injection pipe 6 for spraying pure water onto the furnace core tube 4 on the roller 5 is disposed at the upper part of the side inner wall of the third cleaning tank 3. In such a cleaning device, the vicinity of both ends of the furnace core tube 4 are supported by arms 7 each bent in an arc shape at the bottom, and the core tube 4 is immersed in an etching solution 8 in the first cleaning tank 1 to adhere to the inner wall of the furnace core tube 4. After that, the arm 7 is raised, moved horizontally, and lowered, and the core tube 4 is placed in the cleaning liquid 9 made of pure water in the second cleaning tank 2 to wash away the etching liquid and the like.

Furthermore, the arm 7 is moved to remove the reactor core tube 4 from the third cleaning tank 3.
It is placed on the inner roller 5. Then, as shown in FIG. 2, a pure water supply pipe 12 is connected to a fine pipe (branch pipe) 10 at one end of the reactor core tube 4 via a rotatable rotary joint 11, and the pure water supply pipe 12 is connected to the reactor core. Pure water is poured into the tube 4 to clean the inside of the tube. Further, pure water is sprayed onto the core tube 4 from the upper injection pipe 6 to wash the outer wall of the core tube 4. At this time, since the rollers 5 both rotate in the same direction, the furnace core tube 4 continues to rotate in a constant rotation direction, and the cleaning liquid flows over the entire inner and outer walls of the furnace core tube 4 to perform cleaning. However, such a cleaning device has the following drawbacks.

{1) When cleaning in the third cleaning tank, a rotary joint must be connected to the reactor core tube each time cleaning is performed, resulting in poor work efficiency.

'2' The pure water supply pipe is connected to the reactor core tube via a rotating joint, so normally there is no way that the pure water supply pipe would be affected by the rotation of the reactor core tube, but in reality the rotary joint Since the vicinity is not a fixed structure, the pure water supply pipe is imprinted, the supply of pure water fluctuates, and the inside of the pipe cannot be sufficiently cleaned.

{3' Since the pure water supply pipe runs along the bottom of the third cleaning tank, there is a risk that the rubbery pure water supply pipe will be corroded by the acid, creating new impurities and contaminating the reactor core tube. .

{4} The branch pipe portion of the furnace tube has a structure in which one end of the furnace core tube is rapidly constricted, and the cleaning liquid flows from the plate tube into the large diameter portion of the furnace core tube.

As a result, a vortex of flow is generated in the constriction region, and the metabolism of the cleaning fluid is extremely slow in this region, making it impossible to sufficiently clean the inner wall of the constriction curved surface of the reactor core tube. '5} Since there are no large-diameter rotary joints on the market for reactor core tubes without plate tubes, such cleaning equipment cannot clean them. In other words, it has low versatility. ■ When the reactor core tube is inserted into and removed from the liquid in the first and second cleaning tanks, the structure is such that the reactor core tube is inserted and removed horizontally, so when submerging the reactor core tube into the liquid, the branch pipe side is not blocked. This may also result in insufficient air leakage within the pipe.

Due to the small air bubbles remaining in the tube, etching and cleaning are not possible, and the etching and cleaning cannot be performed effectively due to the formation of parts. In addition, since the air inside the tube is difficult to leak, the tube may float and the set position may shift, resulting in insufficient support by the arm or the inability to place the tube on the roller as specified. or Therefore, an object of the present invention is to provide a tubular object cleaning device that can perform sufficient cleaning and has high working efficiency.

Another object of the present invention is to provide a highly versatile cleaning device for tubular objects.

In order to achieve such an object, one embodiment of the present invention includes a first cleaning tank containing an etching solution, a second cleaning tank containing pure water, and rotating the core tube and applying pure water to the outer peripheral surface of the core tube. A core tube cleaning device comprising a third cleaning tank serving as a mechanism group for spraying water and flowing pure water into the tube from one end of the core tube, and a transfer device for sequentially moving the core tube in and out of each of these cleaning tanks. The pipe cleaning mechanism of the third cleaning tank is provided with liquid jetting means such as a pure water jetting mechanism that sprays pure water from the large-diameter entrance side of the core tube toward the inner wall of the core tube.

In addition, the transfer mechanism is designed to prevent the furnace tubes from floating above the liquid surface and to prevent air from remaining in the furnace tubes when the furnace tubes are immersed in the liquid of each cleaning tank. The structure has a support mechanism that temporarily supports the reactor core tube several times obliquely so that water can drain well from the reactor core tube when the reactor core tube is removed from the liquid. The invention will be illustrated by way of example. 3 to 7 a to 7 d show an embodiment of the furnace tube cleaning device of the present invention.

In this embodiment, in the core tube cleaning device shown in FIGS. 1 and 2, the structure of the third cleaning tank 3 is partially improved,
Moreover, the transfer mechanism including the arm 7 that supports the reactor core tube 4 is improved. That is, four rollers 5 are mounted on the bottom plate 13 of the third cleaning tank 3, and each pair of rollers 5 supports the vicinity of both ends of the furnace tube 4, respectively. Further, one connecting shaft 14 is fixedly fixed and passes through the center of the two rollers 5 located on one side. This connecting shaft 14 is connected via a coupling 18 to a rotating shaft 17 of a motor 16 disposed under a cover 15 at one end of the third cleaning tank 3, and is rotated by the drive of the motor 16. There is. Therefore, when the hearth tube 4 is placed on the loaf 5 and the motor 16 is driven, the hearth tube 4 is rotated by the rollers 5. In addition, the third cleaning tank 3
A pure water injection mechanism 19 for spraying a cleaning liquid made of pure water is disposed on the cover 15 side. This pure water injection mechanism 19
It consists of a jet nozzle 20 that spouts out pure water, and a supply pipe 21 that guides the pure water to the jet nozzle 20'. The jet nozzle 20 also has a swinging section 22 that swings the jet nozzle up and down. Also, the third
At the top of both inner walls of the cleaning tank 3, there are a plurality of injection holes (not shown) for spraying pure water onto the reactor core tube 4 layered on the rollers 5.
An injection pipe 6 having a diameter is provided. On the other hand, the transfer mechanism for transferring the furnace core tube 4 has a structure shown in FIG.

That is, two rails 23 are disposed above the first to third cleaning tanks 1 to 3 so as to cross them together, and a movable box 24 is mounted on these rails 23 via wheels 25. There is. The rotation of this wheel 25 is controlled by a motor system (not shown). Further, from the bottom surface of the movable box 24, the lower end thereof is bent in an arc shape, and two arms 7 extend from the bent portion on which the furnace core tube 4 is placed. The upper ends of these arms 7 are each fixed and supported by a lifting plate 26 inside the movable box 24.
These elevating plates 26 extend vertically within the movable box 24.
It slidably competes with the guide 27 of the book. Further, a threaded rod 28 parallel to the guide 27 is screwed into the lifting plate 26, and the upper end of this threaded rod 28 is connected to the upper surface of the ceiling plate 30 of the movable box 24 via a support plate 31 via a coupling 29. It is connected to a rotating shaft 33 of an elevating motor 32 which is fixed. Therefore, in a support mechanism consisting of an arm, an elevating plate, a screw, a motor, etc., when the elevating motor 32 is rotated in the normal direction, the elevating plate 26 is lowered, so the arm 7 is also lowered, and the elevating motor 32 is reversely rotated. When this is done, the elevating plate 26 rises. In addition, the two arms 7 can be individually controlled up and down. Next, the cleaning operation by such a core tube cleaning device will be described with reference to FIGS. 6 a to 6 e and 7 a to d.

First, after hooking the reactor core tube 4 to the arm 7 of the transfer mechanism,
The transfer mechanism is stopped directly above the first cleaning tank 1, and as shown in FIG.
As shown in b, the lifting motors 32 of the two sets of support mechanisms are both rotated in the forward direction to lower the furnace tube 4 while keeping it in a horizontal state. Then, when the lower surface of the furnace tube 4 comes into contact with the etching liquid 8, the lowering of the arm 7 of one support mechanism is stopped, and only the lowering of the arm 7 of the other support mechanism is continued. The stop-side arm 7 supports the branch pipe 10 side of the reactor core tube 4. Therefore, as shown in FIG. 2c, the furnace tube 4 enters the etching solution 8 from its large opening. Since this large-diameter side is a straight circular tube, the etching solution smoothly enters the tube without floating the tube. Next, as shown in d in the same figure, the other arm 7 is stopped, and one arm 7 is
is lowered and the furnace core tube 4 is placed into the etching solution from its branch tube side.

At this time, since the etching solution flows into the branch pipes from the major side as well, the furnace core tube 4 does not float up. Also, branch pipe 1
0 is located below the large part of the reactor core tube 4, the lowering of one arm 7 is stopped, and the other arm 7, which has been in a stopped state, is gradually lowered, The reactor core tube 4 is suspended horizontally in the etching solution 8, and the deposited layer inside the reactor core tube is etched. In this manner, since the furnace core tube 4 is alternately immersed in the etching liquid in an oblique state, no air bubbles remain in the furnace core tube. Next, when the undesired adhesion layer on the tube wall is dissolved by etching,
The furnace core tube 4 is lifted out of the etching solution on a daily basis as shown in FIGS. That is, as shown in FIG.
As shown in figure b, one arm 7 is raised and the branch pipe 1 is
The furnace core tube 4 is tilted so that 0 is in the upper position. Next, both arms 7 are raised together in this state. As a result, the bottom surfaces of the inner walls of the furnace core tubes through which the etching solution flows are all inclined in the same direction, that is, as shown in FIG. After the core tube 4 is lifted onto the etching solution in an inclined state, one arm 7 on the side of the branch tube 10 stops rising, and the other arm 7 rises, causing the core tube 4 to rise as shown in d in the same figure. is in a horizontal state. Next, the transfer mechanism moves and stops above the second cleaning tank 2, and the core tube 4 is immersed in the cleaning liquid (pure water) for a certain period of time in the same manner as described above to clean the inner and outer walls of the core tube. do. Next, the transfer mechanism transfers the reactor core tube 4 into the third cleaning tank 3, as shown in FIGS. 3 and 4.

The furnace core tube 4 is placed on the rollers 5 with its large section branched toward the jet nozzle 20 side. At this time, the bent portion of the arm 7 is slightly removed downward from the lower surface of the furnace core tube 4. Then, since the motor 16 is driven and the roller 5 rotates, the furnace core tube 4 rotates, and at the same time, pure water is blown out from the injection tube 6 to clean the outer peripheral wall of the furnace core tube 4. At the same time, pure water is also jetted from the jet nozzle 20, and this water stream hits the inner wall of the rotating reactor core tube 4. In addition, since the swinging part 22 of the jet nozzle 20 swings its head, the water flow is
Since it moves along the generatrix of the tube, the entire inner wall of the furnace tube 4 is cleaned due to the rotation of the furnace core tube. In addition, the water flow hits the inner wall of the constrictor and the inner wall of the branch pipe with great force, allowing for effective cleaning. Note that the dirty cleaning liquid is drained from the drain port 34. After cleaning for a certain period of time in this way, the injection of pure water from the jet nozzle 20 and the injection pipe 6 is stopped, and the rotation of the motor 16 is also stopped. Then, the arm 7 rises and the cleaned reactor core tube 4 is carried to a predetermined position, completing a series of cleaning operations. Thus, according to the embodiment,
When immersing the reactor core tube into the etching solution and cleaning solution, it is possible to immerse the reactor core tube into the etching solution and cleaning solution without leaving any air remaining in the tube. Also,
Since the water stream can be applied vigorously to the pipe wall, it is possible to completely remove and clean the undesirable film adhering to the pipe wall. Furthermore, according to this embodiment, there is no need to connect a pure water supply pipe or the like to a branch pipe of the reactor core tube via a rotary joint in order to flow the cleaning liquid into the reactor core tube, so that work efficiency is improved.

Further, since there is no pure water supply pipe made of rubber or the like in the third cleaning tank, there is no possibility of being attacked by the etching solution and no new impurities are generated. Therefore, recontamination of the reactor core tube does not occur.
Further, in this embodiment, since the structure is such that water is sprayed onto the inner wall of the tube from one end of the entrance, even a core tube without branch pipes can be reliably cleaned, and is highly versatile.

In addition, in this embodiment, the structure is such that the tube can be immersed and taken out by tilting it appropriately when entering and exiting the liquid. It does not float and move relative to the arm.

Therefore, in the former case, the uniformity of etching and cleaning is maintained, and in the latter case, the reactor core tube is supported on an arm or on a roller in a desired state, and automation is also possible. Note that the present invention is not limited to the above embodiments.

For example, jet nozzles may be used in liquids. As described above, according to the core tube cleaning device of the present invention, it is possible to provide a core tube cleaning device that provides sufficient cleaning, high work efficiency, and excellent versatility.

[Brief explanation of the drawing]

Figures 1 and 2 are partial explanatory diagrams of the furnace D pipe cleaning device, with Figure 1 being an operational diagram showing the cleaning operation, and Figure 2 showing the state of cleaning inside and outside the core tube in the third cleaning tank. It is a partially sectional view. 3 to 7 a to 7 d show an embodiment of the core tube cleaning device of the present invention, FIG. 3 is a partial sectional view of the third cleaning tank, FIG. 4 is a partial plan view, and FIG. Figure 5 is a cross-sectional view showing a part of the transfer mechanism, Figures 6 a to e are operational diagrams showing the state of immersion of the core tube into the liquid, and Figures 7 a to d are the removal of the core tube from the liquid. It is an operation diagram showing a true state. 1...First cleaning tank, 2.
...Second cleaning tank, 3...Third cleaning tank, 4
...Furnace tube, 5...Roller, 6...
... Injection pipe, 7 ... Arm, 8 ... Etching liquid, 9 ... Cleaning liquid, 10 ... Inspector (branch pipe), 11 ... Rotation Join, 12...
・Pure water supply pipe, 13...Bottom plate, 14...Connection shaft, 15...Cover, 16...Motor, 17
...Rotating shaft, 18...Coupling,
19...Pure water injection mechanism, 20...Jet nozzle, 21...Supply pipe, 22...
・Hyakushibu, 23...Rail, 24...
Movable box, 25...wheels, 26...lifting plate,
27...Guide, 28...Nejisha, 2
9... Coupling, 30... Ceiling plate, 31... Support plate, 32... Lifting motor, 33... Rotating shaft, 34 ...Drain port. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] 1 (a) a mechanism for rotating the tubular object to be treated around an axis of rotational symmetry; (b) a liquid jetting means for supplying a treatment liquid or cleaning water to the inner surface of the tubular object to be treated; and (c)
A cleaning device for a tubular object to be processed, comprising a liquid supply means for supplying a processing liquid or cleaning water to the outer surface of the tubular object to be processed.