JPH02102141A - Rectangular tank made of quartz glass - Google Patents

Abstract

PURPOSE:To form the connected portions of connecting members at readily grindable positions to eliminate the migration of dusts mixed in a treating solution into welded portions by combining the connecting members selected from arcuate, curved plate-like and flat plate-like members having specific shapes, respectively, with each other to form the connected portions of the connecting members at readily grindable positions. CONSTITUTION:Connecting members selected from arcuate members 10A and 10B prepared by longitudinally dividing a cylindrical tube, at least partially curved plate- like members 20A-20C and flat plate-like members 30 having widths smaller than the respective wall surface widths of a rectangular tank are combined with each other. The connected portions 40 of the respective glass members are welded to form the rectangular tank. Thereby, the connected portions can be readily ground with a grinder to smooth the welded mark portions. The curved plate-like members include members 20C having rifted portions in the whole regions of the central four side peripheries thereof, U- or L-shaped members 20B each prepared by bending a prescribed portion of the member 30 and J-shaped members 20A. Further, the arcuate members include members each prepared by longitudinally dividing a cylindrical tube having a roundly sealed tip or a cylindrical tube having openings at both the tips thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a square quartz glass container with an open top, preferably a square quartz glass tank used as a cleaning tank for semiconductor wafers, a chemical treatment tank, etc. .

``Prior art'' For example, in cleaning tanks for semiconductor wafers and chemical processing tanks, processing tanks made of quartz glass are generally used to ensure chemical stability and avoid elution of impurities, but the shape of the processing tanks is It is usually formed into a rectangular shape with an opening at the top for convenience of operation and to accommodate the shape of the carrier that accommodates the semiconductor wafer.

Conventionally, such a square-shaped processing tank (hereinafter referred to as a square tank) is made by welding five flat quartz glass plates forming the bottom and four side surfaces into a square shape, and then forming a square container.
It is manufactured by removing welding marks on the container using a grinder, etc., but since the shape of the grinder is disc-shaped or belt-shaped, welding marks are present, especially in the concave ridgeline part located on the inner circumference side. Removing welding marks requires a great deal of effort and skill, and it is particularly difficult to completely remove welding marks located at the corners.

For this reason, in the past, some of the ridge lines were used as a processing tank for introducing chemicals and cleaning solutions while leaving welding marks, but for example, during bubbling cleaning, fine particles such as particles that migrated from the wafer to the cleaning solution If dust gets into the welding trace, it cannot be easily scattered even if the tank is cleaned using hydrofluoric acid.

However, since the rectangular tank has a structure in which many welding marks are formed on the four sides of the bottom surface and the corners thereof, which are the sites where particles are deposited, the intrusion becomes even more common.

And once the dust gets into these welding marks, it is not only difficult to remove as mentioned above.

During reuse, the wafer may return to the cleaning solution, which may re-adhere to the wafer and cause product defects, making it impossible to perform effective cleaning.

"Problems to be Solved by the Invention" In order to eliminate such drawbacks, the bottom surface 1 as shown in FIG.
A so-called developed quartz glass plate 100 is formed in which four side wall surfaces 100b are integrally connected to each side of the quartz glass plate 100, and the side wall surface portions 100b of the quartz glass plate 100 are erected to form a joint portion 101. A technique for welding is disclosed, but in this technique, no joints are formed on each side around the bottom surface, but on the vertical ridge line rising from the bottom corner and the bottom corner. However, since joints are naturally formed, the above-mentioned drawback that these weld marks cannot be completely removed cannot be overcome.

For this reason, for example, in Japanese Patent Application Laid-Open No. 58-8812!3, a powdered quartz glass raw material and a core are used in a rotary melting furnace without forming a square quartz glass tank using a plurality of quartz glass members. A technique of filling the gap between the wall surface and the core with quartz glass powder, pulling out the core while rotating the furnace, and then heating and melting the raw material powder with an arc flame or gas flame to form the square tank. However, since such technology adopts a configuration in which the raw material powder is directly melted, it is difficult to form a large square tank, and since the raw material powder comes into direct contact with the furnace wall, impurities are likely to be mixed in. However, it is not suitable for manufacturing processes that involve mass processing of large-diameter and highly integrated wafers, as has been the case in recent years.

In view of the drawbacks of the prior art, the present invention forms a quartz glass square tank by welding the joints of a plurality of quartz glass members, while forming the joints of the glass members at a position that is easy to grind with a grinder. However, it is an object of this invention to provide a rectangular tank in which the welding traces are smoothed and particles mixed in the cleaning liquid or processing liquid do not enter the welding traces.

"Means for Solving the Problems" In order to achieve such technical problems, the present invention provides arc-shaped members 10A and 10B formed by vertically dividing a cylindrical tube, and a plate-shaped member at least partially curved. (Hereinafter referred to as a curved plate member) The square tank was formed by combining members selected from 2OA, 20B, and 20G and the flat plate member 30 formed with a width smaller than each wall width of the square tank. The main points are the main points.

In this case, the curved plate-like member is made by bending a predetermined portion of the flat plate-like member 30, which has a width smaller than the width of each wall surface of the member 20C1 whose central part in FIG. It also includes a member 208 bent into a "U" or L-shape, and a member 2OA formed into a 3-shape by curving only the tip end of one side.

In addition, although the flat member 30 may be used in the present invention, it is a premise that the member 30 has a length in the vertical and horizontal directions that is smaller than the width of each wall surface of the square tank.

Further, the arc-shaped member includes a cylindrical tube 1 having a rounded end.
It includes both the cylindrical tube 0A and the cylindrical tube 10B with both ends open.

That is, the arc-shaped member is a cylindrical tube IA with both ends cut in a direction perpendicular to the axis, as shown in FIG.

The arc-shaped member 10A is formed by dividing each of the cylindrical tubes IB with rounded ends into four along the axial direction.

Two types of 10B are used. Here, each of the cylindrical tubes IA, 1
The reason for dividing B into four parts is the arc-shaped member 10A.

This is because 10B is arranged at a corner where a ridge line and a plurality of ridge lines gather, so it corresponds to the included angle of 30 degrees, but it is not necessarily limited to dividing into four parts. It may be divided into 6 or 3 parts.

The reason for using the arc-shaped members 10A and IOB is shown in Fig. 1 (b
) and Fig. 2(b), when joining members installed on adjacent ridgeline parts, if they are directly joined, the joint will be located on the ridgeline and corner. It ends up.

Therefore, the arc-shaped member 10A and IOB are interposed on the ridgeline to avoid direct connection between the two, in other words, to prevent the joint 40 from being located on the ridgeline and corner, and in this case, If an arc-shaped member 10A as shown in FIG. 4(a) is simply used, wedge-shaped spaces will be formed at the corners. Therefore, preferably, the wedge-shaped space is formed by using an arc-shaped member 10B formed by vertically dividing a sealed cylindrical tube IB as shown in FIG. 4(b) as a member located on the ridge line. This makes it possible to avoid the joint portion 40 from being located on the ridgeline and corner portion without being damaged.

"Operation" Therefore, according to the present technical means, first, since the flat member 30 is formed with a width smaller than the width of each wall surface of the square tank, it is located at a corner where a ridge line and a plurality of ridge lines gather. The sides and corners of the flat plate member 30 are not located at all in the member, and at least the arc members 10A and IOB formed by vertically dividing the cylindrical pipes IA and IB, or the curved plate member 2OA, It is either 20B or 20G.

As explained in detail in the previous section, the present invention includes such arc-shaped members 10A, IOB, and curved plate-shaped members 2OA, 20B.
.

By effectively utilizing the 20C curved surface, it is possible to weld the joint 40 between these members at least at a position away from the ridge line and the corner where a plurality of ridge lines gather, and this point is really important. This is a feature of the invention.

"Embodiments" Hereinafter, preferred embodiments of the present invention will be described in detail by way of example with reference to the drawings. However, unless otherwise specified, the dimensions, materials, shapes, and relative arrangements of the components described in this example are not intended to limit the scope of this invention, but are merely illustrative examples. Although FIGS. 1 to 3 show each embodiment of the present invention, the wall thickness is exaggerated for clarity of explanation, and the actual wall thickness is This is the extent shown in the description of the cylindrical tubes IA and 1B in the figure.

FIG. 1 shows the two types of arcuate members (hereinafter referred to as a arcuate member 10A
A square tank formed using a flat member 30 having a width smaller than the width of each wall surface of the square tank, and a bottom wall as shown in FIG. 1(a). A-arc-shaped members 10A are arranged on the four sides of the corners, and b-arc-shaped members 10B are arranged on the vertically erected ridgeline portions sandwiched between the a-arc-shaped members 10A on each two adjacent sides, and A flat member 30 of a corresponding shape is disposed in each plane space sandwiched between these arc-shaped members 10A and IOB.

As a result, as shown in FIG. 1(b), the joint 40 can be formed avoiding ridge lines and corners, and welding marks on the joint 40 can be easily removed using a grinder.

FIG. 2 shows two types of curved plate-like members, three-shaped and U-shaped (hereinafter distinguished as J-shaped member 20B and U-shaped member 20A),
b A square tank formed using the arc-shaped member 10B, as shown in Fig. 2 (
As shown in a) and (b), first, the two side wall surfaces facing the bottom surface are connected and formed by the U-shaped member 2OA, and the joint portion 40 is located at the ridgeline portion formed between the other two side wall surfaces and the bottom surface. In order to avoid this, a J-shaped member 20B in which the bottom edge of the flat plate-shaped member 30 is curved in an R shape is used, and the J-shaped member 20B is brought into contact with the ventral side of the U-shaped member 2OA, and the other pair of sides are form a wall surface. Then, b-arc-shaped members 10B are respectively disposed on the vertically erected ridgeline portions sandwiched between the two members to form a square tank.

As a result, as shown in FIG. 2(b), the joint 40 can be formed avoiding ridge lines and corners, and welding marks on the joint 40 can be easily removed using a grinder.

Figure 3 shows a rectangular tank formed using two types of curved plate-like members, U-shaped and tray-shaped (the latter is referred to as the tray-shaped member 20G), and the bottom is formed as shown in Figure 3 (a). tray-shaped member 20G
A square tank can be easily formed by installing a pair of U-shaped members 2OA along the periphery of the upper surface side, with the center line sandwiched therebetween. The tray-shaped member 20G as described above can be formed relatively easily by heating the peripheral edge of the flat plate-shaped member 30 with an oxyhydrogen gas burner to soften and bulge it.

As a result, as shown in FIG. 3(b), the joint 40 can be formed avoiding ridge lines and corners, and welding marks on the joint 40 can be easily removed using a grinder.

"Effects of the Invention" As described above, according to the present invention, although a quartz glass square tank is formed by welding the joints of a plurality of quartz glass members,
To obtain a square tank in which a joint part of the glass member is formed at a position where it can be easily ground by a grinder, thereby forming a smooth weld mark part, and preventing particles mixed into a cleaning liquid or a processing liquid from entering the weld mark. As a result, it is possible to significantly suppress the adhesion of particles to the wafer surface in each manufacturing process that uses a square processing tank, such as during the cleaning process or the chemical treatment process, and its practical value is extremely large.

[Brief explanation of drawings]

1 to 3 show quartz glass square vessels according to embodiments of the present invention, in which (a) is an overall perspective view, and (b) is an enlarged perspective view of the main parts. FIGS. 4(a) and 4(b) are operational views showing the manufacturing procedure of the arc-shaped member used for the horny layer, and FIG. 5 is a perspective view showing the manufacturing procedure of the quartz glass square tank according to the prior art. Patent applicant: Yamagata Shin-Etsu Quartz Co., Ltd. (a) and 20C (b)

Claims (1)

[Claims] 1) A quartz glass rectangular tank formed by welding joints of a plurality of quartz glass members, including an arc-shaped member formed by vertically dividing a cylindrical tube, and at least a portion of which is curved. The square tank is formed by combining selected members from among the plate-like members formed with a width smaller than the width of each wall surface of the square tank, and the joints between these members. 2) The member located at the corner where the ridgeline and the plurality of ridgelines gather, 3) The quartz glass square tank according to claim 1, which is either an arc-shaped member or the curved plate-shaped member; The quartz glass square tank according to claim 1), which is an arc-shaped member, preferably formed by vertically dividing a sealed cylindrical tube.