JPH04317780A - Washing apparatus - Google Patents

Abstract

PURPOSE:To sufficiently wash an object to be washed such as a quartz tube within a short time. CONSTITUTION:A washing apparatus is equipped with a washing tank 1 having an opening part provided to the upper part thereof and also having drain ports 5a, 5b respectively provided to the bottom surface 4 thereof, rotary mechanisms 3, 3 holding a quartz tube in the washing tank 1 to rotate the same and the water injection pipe 2b horizontally arranged to the upper part of the washing tank 1. The injection amount of water of the water injection pipe 2b is set so as to be larger than the drain amount from the drain port 5a, 5b so that pure water overflows from the upper opening of the washing tank 1. The flow area of the drain ports provided to the bottom surface 4 of the washing tank is set so that the total area of the drain hole 5a of the side edges of the washing tank are made larger than that of the drain ports 5b of the central part thereof in order to accelerate the flow of pure water of the side edge parts of the washing tank.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device for quartz tubes and the like.

0002

2. Description of the Related Art For example, a dry etching apparatus using reactive gas plasma is used for etching a CVD deposited film. In this dry etching apparatus, a quartz tube, which is a transparent insulator, is usually used to enable observation of the progress of the reaction inside the apparatus and to provide electrical insulation. However, as this dry etching apparatus is used for a long period of time, the inner surface of the quartz tube may become contaminated with reaction products during etching, and its transparency and insulation properties may be impaired. Contaminants on the quartz tube are usually removed by chemical treatment followed by pure water cleaning.

FIG. 2 shows a conventional quartz tube cleaning device used for this pure water cleaning. Figure (A) is a sectional view of the cleaning device viewed from the side, and Figure (B) is a plan view of the bottom of the cleaning tank.

The cleaning tank 1 shown in FIG. 1A is a rectangular parallelepiped container made of vinyl chloride, and has an opening at the top for introducing a quartz tube or the like. Two water injection pipes 2a and 2b are provided to supply pure water into the cleaning tank 1. The first water injection pipe 2a is not used during cleaning, but functions as a faucet for previously injecting pure water into the cleaning tank 1 before introducing the quartz tube. The second water injection pipe 2b is arranged to run horizontally at the upper corner of the cleaning tank 1, and has many holes on its side so that it can discharge pure water horizontally during cleaning of the quartz tube. It is something that

In order to hold the quartz tube introduced into the cleaning tank 1 through the upper opening to a position lower than the opening and to rotate the quartz tube in this position during cleaning, a rotating shaft, a rotating plate and a rotary plate are respectively provided. A rotation mechanism 3, 3 having two shafts constituted by bearings is further provided. The power generated by the motor is transmitted to each rotating shaft via transmission gears. Two rotating plates for supporting a quartz tube are attached to each rotating shaft, each supported by a bearing, at a distance from each other in the axial direction. The second water injection pipe 2b and the rotating shafts, rotating plates, and bearings constituting the rotating mechanisms 3, 3 are all made of vinyl chloride, similar to the cleaning tank 1, since they all come into contact with pure water.

The operation of the conventional quartz tube cleaning device described above will now be described. First, prior to cleaning, pure water is injected into the cleaning tank 1 in advance using the first water injection pipe 2a. Next, the quartz tube treated with the chemical solution is introduced into the cleaning tank 1 from the upper opening using an elevator. When the introduced quartz tube is supported by the rotating plates of the rotating mechanisms 3, 3, the quartz tube is completely submerged under the water surface. Then, when water injection by the second water injection pipe 2b is started, the same figure (
As shown in B), since the bottom surface 4 of the cleaning tank 1 is not provided with a drain port, pure water overflows from the opening at the top of the cleaning tank 1. At the same time, when the rotation mechanisms 3, 3 are driven to rotate the two rotation shafts in the same direction, the quartz tube is washed while rotating in pure water.

[0007]

[Problems to be Solved by the Invention] In the conventional quartz tube cleaning device described above, the pure water newly injected sequentially through the second water injection pipe 2b does not reach the bottom surface 4 of the cleaning tank.
Almost as is, it overflows from the opening at the top of the cleaning tank 1. In other words, the pure water previously supplied into the cleaning tank 1 remains or circulates within the cleaning tank 1. Accordingly, the contaminants separated from the quartz tube float in the cleaning tank 1, and some of them accumulate on the bottom surface 4 of the cleaning tank. A part of the contaminants accumulated on the bottom surface 4 of the cleaning tank floats again. Only a small portion of floating contaminants that happen to reach near the water surface are discharged through the upper opening as a result of overflow. Therefore, no matter how long the cleaning time is,
Contaminants that were floating just before the end of cleaning re-adhere to the quartz tube after the end of cleaning.

[0008] If a quartz tube that has been insufficiently cleaned is used again for product processing in a dry etching device, residual contaminants will peel off from the quartz tube during product processing and mix into the product as particles, causing problems in product processing. cause.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a cleaning device that can sufficiently clean objects to be cleaned such as quartz tubes of the dry etching device in a short time. shall be.

0010

[Means for Solving the Problems] In order to achieve the above object, the present invention creates a flow of cleaning liquid such as pure water from the top to the bottom in a cleaning tank to remove contaminants separated from the object to be cleaned. In order to prevent floating and stagnation of the cleaning liquid, an outlet for discharging the cleaning liquid during cleaning is provided at the bottom of the cleaning tank.

[0011] To explain concretely, the invention of claim 1:
A cleaning tank having an opening at the top and an outlet for discharging the cleaning liquid at the bottom, holding means for holding the object to be cleaned at a position lower than the opening in the cleaning tank, and the cleaning liquid overflowing from the opening. In this way, a configuration is adopted that includes a cleaning liquid injecting means for injecting a larger amount of cleaning liquid into the cleaning tank from the upper part of the cleaning tank than the amount of cleaning liquid discharged from the discharge port.

[0012] According to a second aspect of the invention, the holding means is provided with a rotation mechanism for rotating the object to be cleaned in the cleaning liquid.

[0013] According to the third aspect of the invention, the discharge ports are provided at the side edges and the center of the bottom of the cleaning tank, and the flow area of the discharge ports at the side edges is larger than the flow area of the outlet at the center. This configuration adopts the following configuration.

[0014]

According to the first aspect of the invention, a part of the cleaning liquid is discharged during cleaning from the outlet provided at the bottom of the cleaning tank. Furthermore, since a larger amount of cleaning liquid than the amount of cleaning liquid discharged from the discharge port is injected into the cleaning tank from the upper part of the cleaning tank by the cleaning liquid injection means, the cleaning liquid overflows from the opening provided at the upper part of the cleaning tank. The object to be cleaned is held by the holding means at a position lower than the upper opening in the cleaning tank, so that it is completely immersed in the cleaning liquid. At this time, as mentioned above, a part of the cleaning liquid is discharged from the outlet at the bottom of the cleaning tank during cleaning, so a flow of the cleaning liquid from the top to the bottom is created in the cleaning tank, causing contamination that has separated from the object to be cleaned. The object is discharged through the outlet together with the cleaning liquid by the flow of the cleaning liquid. In addition, floating contaminants that reach the top of the cleaning tank are
As it overflows, it is discharged from the upper opening. In other words, the contaminants separated from the object to be cleaned do not remain suspended in the cleaning tank or accumulate on the bottom of the cleaning tank, and are completely discharged from the cleaning tank. Therefore, contaminants will not re-adhere to the object to be cleaned at the end of cleaning. Moreover, since the fresh cleaning liquid sequentially poured from the top of the cleaning tank hits the object to be cleaned as it flows downward, the cleaning efficiency is good.

According to the second aspect of the invention, the object to be cleaned is rotated in the cleaning liquid by the rotation mechanism, and the downward flow of the fresh cleaning liquid successively injected from the top of the cleaning tank is directed to different surfaces of the object to be cleaned. are applied sequentially, further improving cleaning efficiency.

[0016] The cleaning liquid tends to accumulate on the side edges of the bottom of the cleaning tank compared to the center of the bottom, and contaminants separated from the objects to be cleaned tend to accumulate there. However, according to the invention of claim 3, the flow area of the cleaning liquid outlet provided at the bottom of the cleaning tank is made larger at the side edges of the bottom than at the center of the bottom, so that the flow of the cleaning liquid at the side edges of the bottom is increased. This increases the efficiency of pollutant discharge.

[0017]

[Embodiment] Fig. 1 is a diagram showing a quartz tube cleaning device as an embodiment of the cleaning device of the present invention, in which (A) is a sectional view of the cleaning device viewed from the side, and (B) is a cleaning device. FIG. 3 is a plan view of the bottom of the tank.

[0018] The cleaning tank 1 in the same figure (A) has a depth of 400 m.
It is a rectangular parallelepiped container made of vinyl chloride with a size of 3,450 mm in width and 400 mm in depth, and has an opening at the top for introducing a quartz tube and the like. Furthermore, as shown in the same figure (B), there is a φ3
A large number of drain ports 5a and 5b each having two types of flow areas, 0 mm and φ20 mm, are provided. To explain in more detail, two side edges 4a (
Fifty-eight side edge drain ports 5a each having a diameter of 30 mm are provided along a length of 3450 mm at intervals of 60 mm such that their peripheral edges are in contact with the side edge 4a. Of these, the ones at both ends in the width direction also touch the side 4b (length 400 mm) in the depth direction of the bottom surface 4 of the cleaning tank. On the vertical bisector of this side 4b in the depth direction, there are 86 central drainage ports 5b each having a diameter of 20 mm.
are lined up at intervals of 40 mm, and of these, the ones at both ends in the width direction are in contact with the side 4b in the depth direction of the bottom surface 4 of the cleaning tank. However, only the center distance between 43rd and 44th is 70mm.
It has become.

In order to supply pure water into this cleaning tank 1,
Two water injection pipes 2a and 2b are provided as in the conventional case. The first water injection pipe 2a is not used during cleaning, but functions as a faucet for previously injecting pure water into the cleaning tank 1 before introducing the quartz tube. Second
The water injection pipe 2b has a diameter of 30 mm and a length of 3300 mm, and is arranged to run horizontally in the width direction at the upper corner of the cleaning tank 1, and can discharge pure water horizontally during cleaning of the quartz tube. There is a 2mm diameter hole on the side for 20m.
A large number of them are provided at intervals of m. However, the amount of water injected by the second water injection pipe 2b is set to be larger than the amount of water discharged by the side drain ports 5a and the center drain port 5b.

In order to hold the quartz tube introduced into the cleaning tank 1 through the upper opening to a position lower than the opening and to rotate the quartz tube at this position during cleaning, a rotating shaft and a rotating shaft are respectively used. A rotating mechanism 3, 3 having two shafts constituted by plates and bearings is further provided. The power generated by the motor is transmitted to each rotating shaft via transmission gears. Two rotating plates for supporting a quartz tube are attached to each rotating shaft, each supported by a bearing, at a distance from each other in the axial direction. To give an example of the dimensions of each member, the rotating shaft is φ30mm and length 3300m.
m, rotating plate φ50mm, thickness 10mm, bearing height 6
0 mm, width 50 mm, and thickness 10 mm. In addition, since the second water injection pipe 2b and the rotating shaft, rotating plate, and bearing that constitute the rotating mechanisms 3, 3 all come into contact with pure water,
Similar to the conventional cleaning tank 1, the material is vinyl chloride.

The operation of the quartz tube cleaning apparatus according to the present embodiment described above will now be described. First, prior to cleaning, pure water is injected into the cleaning tank 1 in advance using the first water injection pipe 2a. Next, the quartz tube treated with the chemical solution is introduced into the cleaning tank 1 from the upper opening using an elevator. When the introduced quartz tube is supported by the rotating plates of the rotating mechanisms 3, 3, the quartz tube is completely submerged under the water surface. When water injection by the second water injection pipe 2b is started, pure water is discharged from the side drain ports 5a and the central drain port 5b provided on the bottom surface 4 of the cleaning tank, and the amount of water drained by these drain ports 5a and 5b is increased. Since the amount of water injected by the second water inlet pipe 2b is set to be larger than the amount of water injected by the second water inlet pipe 2b, pure water overflows from the upper opening of the cleaning tank 1. At the same time, when the rotation mechanisms 3, 3 are driven to rotate the two rotation shafts in the same direction, the quartz tube is washed while rotating in pure water.

At this time, as described above, some of the pure water is discharged from the drain ports 5a and 5b on the bottom surface 4 of the cleaning tank during cleaning, so that a flow of pure water flows from the top to the bottom throughout the cleaning tank 1. The contaminants that are formed and separated from the quartz tube are discharged together with the pure water through the drain ports 5a and 5b by the flow of the pure water. Further, floating contaminants that happen to reach the upper part of the cleaning tank 1 are discharged from the upper opening as a result of overflow. In other words, the contaminants separated from the quartz tube do not remain suspended in the cleaning tank 1 or accumulate on the bottom surface 4 of the cleaning tank 1, and are completely discharged from the cleaning tank 1. Therefore, when the quartz tube is lifted out of the cleaning tank 1 by an elevator at the end of cleaning, contaminants will not be reattached to the quartz tube. Moreover, cleaning tank 1
Since the fresh pure water sequentially injected from the top of the tube hits the quartz tube as it flows downward, the cleaning efficiency is high and the quartz tube can be sufficiently cleaned even if the cleaning time is shortened.

Furthermore, the quartz tube is rotated in pure water by the rotating mechanisms 3, 3, and the downward flow of fresh pure water successively injected from the top of the cleaning tank 1 hits different surfaces of the quartz tube one after another. , cleaning efficiency is further improved. Note that pure water tends to accumulate on the side edges of the cleaning tank bottom 4 compared to the center, and contaminants separated from the quartz tube tend to accumulate there. However, the side edges 4 in the width direction of the bottom surface 4 of the cleaning tank
Since the side drain port 5a having a larger flow area than the central drain port 5b is provided so as to be in contact with the center drain port 5b, the flow of pure water at the side edge of the bottom surface is increased and the efficiency of draining contaminants is improved.

[0024]

[Effects of the Invention] As explained above, according to the invention as claimed in claim 1, since the discharge port for discharging the cleaning liquid during cleaning is provided at the bottom of the cleaning tank, the inside of the cleaning tank can be easily removed. The cleaning liquid flows from the top to the bottom, and the contaminants separated from the object to be cleaned are discharged together with the cleaning liquid through the discharge port. In other words, contaminants separated from the object to be cleaned will not remain suspended in the cleaning tank or accumulate on the bottom of the cleaning tank, and therefore will not re-adhere to the object at the end of cleaning. Nor. Moreover, since the fresh cleaning liquid sequentially injected from the top of the cleaning tank hits the object to be cleaned as it flows downward, the cleaning efficiency is high, and even if the cleaning time is shortened, the object to be cleaned can be sufficiently cleaned.

According to the second aspect of the invention, since the structure includes a rotation mechanism for rotating the object to be cleaned in the cleaning liquid, the downward flow of the fresh cleaning liquid sequentially poured from the top of the cleaning tank is prevented. The cleaning efficiency is further improved by sequentially hitting different surfaces of the object to be cleaned.

According to the third aspect of the invention, the outlet is provided at the side edge and the center of the bottom of the cleaning tank, and the flow area of the outlet at the side edge is larger than the flow area of the outlet at the center. Since a configuration in which the cleaning liquid is larger is adopted, the flow of the cleaning liquid at the side edges of the bottom surface where the cleaning liquid tends to stagnate is larger than that at the center of the bottom surface, and the efficiency of draining contaminants is improved.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a quartz tube cleaning device as an embodiment of the cleaning device of the present invention, in which (A) is a sectional view of the cleaning device viewed from the side, and (B) is a plan view of the bottom of the cleaning tank. It is a diagram.

FIG. 2 is a diagram showing a conventional quartz tube cleaning device, in which (A) is a cross-sectional view of the cleaning device viewed from the side, and (B)
is a plan view of the bottom of the cleaning tank.

[Explanation of symbols]

1...Cleaning tank 2a...First water injection pipe 2b...Second water injection pipe (cleaning liquid injection means) 3...Rotation mechanism (
Holding means) 4...Cleaning tank bottom 5a...Side drain outlet (cleaning liquid outlet) 5b...Central drain outlet (cleaning liquid outlet)

Claims (3)

[Claims] 1. A cleaning tank having an opening at the top and an outlet for discharging cleaning liquid at the bottom; holding means for holding the object to be cleaned at a position lower than the opening in the cleaning tank; A cleaning device comprising cleaning liquid injection means for injecting an amount of cleaning liquid into the cleaning tank from the upper part of the cleaning tank in an amount larger than the amount of cleaning liquid discharged from the discharge port so that the cleaning liquid overflows from the opening. . 2. The cleaning apparatus according to claim 1, wherein the holding means includes a rotation mechanism for rotating the object to be cleaned in the cleaning liquid. 3. The discharge ports are provided at the side edges and the center of the bottom surface of the cleaning tank, and the flow area of the discharge ports at the side edges is larger than the flow area of the outlet at the center. The cleaning device according to claim 1 or 2, characterized in that: