JPH06275595A - Structure of flow regulation plate in washing bath - Google Patents

Abstract

PURPOSE:To obtain an optimum flow rate distribution of a washing liquid. CONSTITUTION:In a washing bath used when performing washing treatment of an object to be washed by a washing liquid, a plurality of spherical members 12 forming a specific size are aligned in plate shape in the structure of a flow regulation plate which is laid out at the bottom of the washing bath for aligning the flow of the washing liquid to be supplied there, thus enabling the holes formed between the spherical members 12 to be an emission hole 13 of the washing liquid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning tank used for cleaning an object to be cleaned using a cleaning liquid,
The present invention relates to the structure of a current plate that regulates the flow of cleaning liquid in a tank.

[0002]

2. Description of the Related Art Generally, as a method for performing a cleaning process of an article to be cleaned immersed in a liquid while overflowing a cleaning liquid such as a chemical liquid, a solvent, and pure water, there are a simple outflow system, an ejection pipe system, and a straightening plate system. There are three.

In the simple outflow system, as shown in FIG. 7A, the cleaning liquid is directly jetted into the tank from the pipe 3 connected to the bottom plate 2 of the cleaning tank 1. In this method, a large liquid flow can be obtained in the connection portion of the pipe 3, that is, in the vicinity of the cleaning liquid ejection hole, but the liquid flow becomes smaller as the distance from the ejection hole increases, so that the cleaning liquid becomes less in the upper layer portion and the corner portion of the cleaning tank 1. There is a drawback that the substitution efficiency is significantly reduced.

In the jet pipe system, as shown in FIG. 7 (b), the jet pipes 7 are arranged at the bottom of the washing tank 1, and the washing liquid is supplied from the pipes 3 connected to the jet pipes 7 into the bath. , Spout pipe 7
The cleaning liquid is spouted from the spouting hole formed in the peripheral wall. This method was proposed to compensate for the drawbacks of the simple outflow method described above, but even in this case, a turbulent flow point is generated in the liquid in the tank and a stagnation portion of the cleaning liquid is observed, and the replacement of the cleaning liquid is caused. The efficiency was not satisfactory.

In the straightening vane system, as shown in FIG. 7C, a straightening vane 8 is arranged at the bottom of the washing tank 1, and a plurality of washing liquids supplied from the pipe 3 to the washing tank 1 by opening and closing the valve 4 are further added. The rectifying plate 8 having the squirt holes is used for squirting. In this method, since the flow of the cleaning liquid supplied to the cleaning tank 1 becomes a laminar flow by passing through the straightening plate 8, the replacement efficiency of the cleaning liquid can be considerably higher than those of the above two systems. In any of the above methods, in order to improve the cleaning effect of the object to be cleaned, the cleaning liquid supplied from the pipe 3 is overflowed from the upper surface of the cleaning tank 1 by opening and closing the valve 4 to flow into the saucer 5, and is drained through the pipe 6 as it is. It is configured.

[0006]

By the way, as shown in FIG. 8, the substrate 9 which is the object to be cleaned is actually stored in the transfer case 10 and is put into the cleaning tank 1 to be placed at the bottom of the cleaning tank 1. When the cleaning liquid is spouted through the arranged straightening plate 8,
The flow of the cleaning liquid in the tank is as shown in FIG. Here, the arrows in the figure indicate the flow direction of the cleaning liquid and also the flow velocity of the cleaning liquid at each position in the tank. That is, the length of the arrow is proportional to the flow rate of the cleaning liquid, and the longer the arrow, the larger the flow rate of the cleaning liquid. As is clear from the figure, when the substrate (object to be cleaned) 9 is placed in the bath, the presence of the substrate 9 causes the cleaning liquid to sneak into the side wall of the cleaning bath 1, and the surface portion of the substrate 9 The flow velocity of the cleaning liquid passing through is extremely smaller than the flow velocity of the cleaning liquid passing near the side wall of the cleaning tank 1. Then, even on the surface of the same substrate 9, the flow velocity of the cleaning liquid decreases as it approaches the center thereof.

Therefore, conventionally, the flow velocity of the cleaning liquid in the tank has been adjusted by changing the size and shape of the ejection holes 8a (see FIG. 8) formed in the straightening vane 8 at each position on the plate. That is, in the portion directly below the substrate 9, the shape of the ejection hole 8a is set to be, for example, a long hole to set a large hole diameter, and in the peripheral portion, the shape of the ejection hole 8a is set to be a round hole and the hole diameter is set to be small. As a result, the flow velocity of the cleaning liquid in the bath becomes maximum at the position directly below the substrate 9, so that when the substrate 9 is actually put in, the substrate 9 becomes a resistance and the flow of the cleaning liquid in the bath becomes substantially uniform. Become.

However, generally, as the material of the straightening vane 8, quartz, which is free from the precipitation of impurities and is excellent in chemical resistance and heat resistance, is adopted. At present, therefore, the straightening vane 8 is difficult because it is difficult to form a hole in the quartz plate. In addition to this, a considerable amount of time and cost will be spent on manufacturing, and in addition to this, if the mutual pitch of the ejection holes 8a is set to be too small, the current plate 8 will be formed at the stage of drilling.
Since cracks and chippings occur on the surface, it has been very difficult to densely eject the cleaning liquid from the straightening vane 8 in the actual cleaning process. Therefore, in the conventional straightening plate 8, it is not possible to obtain an optimum flow velocity distribution (described later) as the flow of the cleaning liquid in the cleaning tank 1, which is a great factor in improving the replacement efficiency of the cleaning liquid and the cleaning effect on the object to be cleaned. It was an obstacle.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a structure of a straightening vane which can easily obtain an optimum flow velocity distribution of the cleaning liquid.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and in a cleaning tank used when cleaning an object to be cleaned stored in a carrying case with a cleaning liquid, A structure of a straightening plate arranged at the bottom of the tank to regulate the flow of the cleaning liquid supplied to the cleaning tank, in which a plurality of spherical members having a predetermined size are spread and arranged in a plate shape, and the spherical members are mutually arranged. The holes formed in between are used as the jetting holes of the cleaning liquid.

[0011]

Since the current plate of the present invention is constituted by arranging a plurality of spherical members arranged in a plate shape, the diameter of the ejection holes formed between these spherical members is large. Variable according to the size. Therefore, by appropriately arranging the spherical members having different sizes in the vertical and horizontal directions or in a zigzag pattern, a large number of ejection holes having different hole diameters are formed at each position of the straightening plate, so that the size and the arrangement of the spherical members are changed. Only with this, it is possible to obtain the optimum flow velocity distribution of the cleaning liquid according to the arrangement state of the object to be cleaned.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a plan view showing an embodiment of a current plate according to the present invention. The current plate 11 of this embodiment
Is arranged at the bottom of a cleaning tank (not shown) and regulates the flow of the cleaning liquid supplied to the cleaning tank, and is composed of a plurality of spherical members 12 having a predetermined size as a whole. The plurality of spherical members 12 are spread and arranged in a plate shape, and the spherical members 1 are arranged in this arrangement state.
A hole formed between the two is used as a cleaning liquid ejection hole 13.

Further, in this embodiment, the spherical member 12 constituting the straightening plate 11 is free from the precipitation of impurities and has chemical resistance.
Quartz spheres are used as a material with excellent heat resistance. As a means for joining the spherical members 12 together, an appropriate pressure is applied from the lateral direction to the plurality of spherical members 12 arranged in a predetermined plane state without using an adhesive or the like that may be a contamination source of the cleaning liquid. By performing the heat treatment, the spherical members 12 are joined together by the welding action of the spherical surface portion.

Here, for reference, the difference in the aperture ratio due to the difference in the size of the spherical member 12 will be described. Here, as an example of calculating the aperture ratio, as shown in FIGS. 2A to 2C, Φ = 5 m in each frame of L = 15 mm square.
A case will be described in which spherical members 12 of m, 7.5 mm, and 15 mm are spread and arranged. When each of these dimensions is applied as a numerical parameter to the formula for calculating the porosity, the porosity is calculated to be 21.5% in any case. However,
Even with the same aperture ratio, as the diameter of the spherical member 12 increases, the diameter of the ejection holes 13 increases and conversely the number decreases.
That is, what should be noted here is that the number and size of the ejection holes 13 can be freely changed only by changing the size of the spherical member 12.

By the way, as described in the above-mentioned conventional example, when the object to be cleaned (the substrate in this example) is put into the cleaning tank, the flow velocity of the cleaning liquid flowing on the surface of the substrate becomes smaller than that of the peripheral portion, and particularly the substrate The tendency is noticeable near the center of. Therefore, as an optimum flow velocity distribution of the cleaning liquid, it is desirable that the flow velocity be highest at the portion toward the central portion of the substrate 9 and gradually lower toward the periphery as shown in FIG.

Taking this into consideration, the structure of the current plate 11 shown in FIG. 1 is as follows: the largest spherical member 12 is arranged at the central portion of the substrate to be put into the cleaning tank, and the periphery thereof. The spherical diameter of the spherical member 12 gradually decreases as the distance increases. Further, due to the arrangement of the spherical members 11, the hole diameter of the ejection hole 13 is the largest at the above-mentioned central portion of the substrate and gradually decreases from that portion. Therefore, in an actual cleaning process, the closer to the central portion of the substrate the cleaning liquid is. The flow velocity increases. As described above, in the current plate 11 of the present embodiment, a plurality of spherical members 12 having different sizes are appropriately arranged according to the arrangement state of the object to be cleaned in the tank, so that the flow velocity distribution of the cleaning liquid in the cleaning tank is obtained. Can easily obtain the optimum distribution state as shown in FIG.

Regarding the way of arranging the spherical members 12, the spherical members 12 are not only arranged vertically and horizontally, but the spherical members 12 are arranged in a staggered manner as shown in FIG. As shown in (b), if the spherical members 12 having different sizes are mixed and arranged vertically or horizontally or in a zigzag manner, the flow rate of the cleaning liquid can be adjusted more finely. FIG. 5 shows the configuration of the current plate 11 that adopts such various arrangement states.

Further, in the above embodiment, about three kinds of spherical members 12 are combined and arranged, but by combining various kinds of spherical members 12 having different sizes or by changing their arrangement state depending on the place. The flow rate of the cleaning liquid can be more finely adjusted according to the size and arrangement of the substrate to be cleaned, and its implementation is very easy.

In addition, in the conventional straightening vane 8, as shown in FIG. 6A, the entrainment of the cleaning liquid (indicated by the arrow) was remarkably observed at the portion passing through the ejection hole 8a. If the plate 11 is adopted, the cleaning liquid can smoothly flow out along the spherical surface of the spherical member 12 as shown in FIG. 6B, and thus the entrapment of the cleaning liquid can be significantly reduced as compared with the conventional case.

[0020]

As described above, according to the present invention,
Since the current plate itself is composed of a plurality of spherical members, the number and diameter of the ejection holes can be freely changed by changing the size and arrangement of the spherical members. Therefore, by appropriately setting the size and arrangement of the spherical members in accordance with the arrangement state of the object to be cleaned, it is possible to easily obtain the optimum flow velocity distribution of the cleaning liquid, which improves the replacement efficiency of the cleaning liquid and the object to be cleaned. The cleaning effect on the object is improved.

Further, in the present invention, since the jetting hole of the cleaning liquid is formed by the spherical surface of the spherical member, the cleaning liquid supplied to the cleaning tank smoothly flows out into the tank along the spherical surface of the spherical member, As a result, the entrainment of the cleaning liquid is reduced in the jetted portion of the straightening vane than in the conventional case.
Further improvement of the cleaning liquid replacement efficiency and improvement of the cleaning effect on the object to be cleaned can be expected.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a current plate according to the present invention.

FIG. 2 is a diagram for explaining an example of calculating a porosity.

FIG. 3 is a diagram illustrating an optimum flow velocity distribution of a cleaning liquid.

FIG. 4 is a diagram illustrating an arrangement state of spherical members.

FIG. 5 is a plan view showing another embodiment of the current plate.

FIG. 6 is a diagram illustrating the flow of cleaning liquid from the ejection holes.

FIG. 7 is a diagram illustrating a typical example of a cleaning method.

FIG. 8 is a perspective view showing an assembled state of a conventional straightening vane system.

FIG. 9 is a schematic diagram for explaining a flow of a cleaning liquid in a conventional example.

[Explanation of symbols]

 11 Straightening Plate 12 Spherical Member 13 Jet Hole

Claims (4)

[Claims] 1. A cleaning tank used for cleaning an object to be cleaned housed in a transport case with a cleaning liquid, the cleaning tank being arranged at the bottom of the cleaning tank to regulate the flow of the cleaning liquid supplied to the cleaning tank. A structure of a straightening plate, characterized in that a plurality of spherical members having a predetermined size are laid out in a plate shape and arranged, and the holes formed between the spherical members are ejection holes for the cleaning liquid. Structure of the current plate in the cleaning tank. 2. The structure of the current plate in the cleaning tank according to claim 1, wherein the spherical members are arranged in a staggered pattern. 3. The structure of the current plate in the cleaning tank according to claim 1, wherein spherical members having different sizes are mixed and arranged. 4. The structure of the current plate in the cleaning tank according to claim 1, wherein the spherical member is made of quartz sphere.