JPH0622262B2 - Method for manufacturing boat for supporting semiconductor wafer - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a boat for supporting semiconductor wafers.

2. Description of the Related Art Conventionally, many types of boats for supporting semiconductor wafers have been proposed.

For example, as shown in FIG. 5, the boat has an inner diameter approximately equal to the diameter of the wafer, and a thick tubular molding is disassembled into two or three parts to form the boat body 10, and the inner surface thereof is formed. A shape / manufacturing method for forming a series of wafer supporting grooves 11 on the side has been proposed, manufactured and used.

Further, as shown in FIG. 6, there is also known a method of forming a boat main body 12 having a cap-shaped cross section in advance and cutting a wafer supporting groove 13 into the boat main body 12 itself to manufacture a boat.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the conventional wafer supporting boat shown in FIG. 5, since the groove 11 is elongated in an arc shape, it takes time to perform the grooving work, and the boat is chipped due to the grooving. Occurrence of defects such as Further, since the groove 11 of the manufactured boat has an arc shape, there is a drawback that the contact area with the wafer is large. In addition, the boat body is too heavy and has a large heat capacity.

In the case of the conventional example shown in FIG. 6, the shape of the boat main body is relatively complicated and the groove 13 is formed in the boat main body, so that the strength tends to be a problem.

The present invention solves the drawbacks of the conventional method for manufacturing a semiconductor wafer supporting boat as described above, reduces the contact area with the wafer, increases the strength, and is lightweight and has a small heat capacity for supporting the semiconductor wafer. It is intended to provide a boat manufacturing method.

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention integrally molds a SiC-based tubular body in which four or more ridges are formed in parallel and longitudinally on an inner surface, The tubular body is cut at at least two locations along a plane that divides the ridge into two parts, and the obtained divided body includes at least three divided ridges at both divided ends.
A gist of a method of manufacturing a boat for supporting a semiconductor wafer is characterized in that after dividing so that at least three ridges are included, a groove for wafer support is formed at each of the at least three ridges.

Example As shown in FIG. 1, first, a tubular body 1 having four or more ridges 2 along the longitudinal direction on its inner surface is integrally molded. Since such a tubular body has a simple shape, it is easy to manufacture, and a known method such as extrusion molding or cast molding can be preferably used for molding.

These ridges 2 are formed in parallel with each other, and are integrally formed mainly with a tubular body main body and SiC. You may form integrally as Si-SiC. A known method for manufacturing a SiC material is used for forming these.

As shown in FIG. 1, the tubular body 1 is divided into a plurality of parts on a plane that passes through substantially the center of the ridge and passes through the center line of the tubular body. When the tubular body is divided into three parts as shown in FIG. 1, if at least six protrusions are formed on the inner surface of the tubular body, the divided boat body will have three protrusions. In the case of the embodiment shown in FIG. 1, nine ridges are formed, and one boat main body divided into three has four ridges.

The ridges can be formed at desired intervals, but if they are formed at equal intervals, they are easy to manufacture.

As shown in FIGS. 2 and 3, a desired number of grooves 3 are formed on the four ridges of the divided boat body 1, and the grooves 3 are formed.
The wafer 4 is put in and supported.

In order to reduce the weight, it is preferable not only to make the boat body 1 thin but also to cut out a part of the boat body 1. For example, as shown in FIG. 4, if the ridge 2 is slightly left and removed in a rectangular shape from the boat body 1, not only the overall weight is reduced, but also the heat capacity is reduced and the heat distribution is good. Becomes

Example 1 First, 40-60% by weight of silicon carbide coarse powder,
Silicon carbide fine powder 60 to 40% by weight, carbon 10 to 20% by weight, methyl cellulose 5% by weight,
13% by weight of water and 2% by weight of a lubricant are mixed and kneaded, and extrusion molding or casting molding is performed, followed by curing and baking, and purification and impregnation with Si, followed by processing. For example, as shown in FIG. 1, nine ridges 2 are formed inside a thin-walled circular tube at equal intervals in parallel and in the longitudinal direction.
The aforementioned kneaded product is molded by extrusion molding or casting molding. The molded product having such a shape is cured and fired. After purifying or impregnating with Si as required,
The circular pipe is divided into three parts so that the boat body 1 having an arcuate longitudinal section is formed as shown in FIG. The four protrusions 2 are integrally formed on the inner surface of the boat body 1. Then, the grooves 3 are formed in the four ridges 2 at predetermined intervals, and the wafer 4 can be supported in the grooves 3.

The ridge 2 may have any desired shape, but it is usually semicircular.

Further, the circular pipe P may be not only divided into three, but also divided into two or four as necessary.

Further, instead of the circular pipe P, a polygonal tubular body may be formed and divided into a plurality of pieces.

It is also possible to form a CVD coating of SiC on the surface of the boat body and / or the ridges.

EFFECTS OF THE INVENTION In the method for manufacturing a semiconductor wafer supporting boat according to the present invention, a wafer supporting boat having high strength can be easily manufactured, and it is formed to divide the tubular body at a position where the ridge is divided into two. The number of ridges can be reduced, and a plurality of boats can be efficiently manufactured from one tubular body.

As shown in Tables 1 and 2, the semiconductor wafer supporting boat manufactured according to the present invention supports the wafer by the ridges 2, so that the contact area with the wafer 4 is small, and the wafer is thermally or pure. Damage is reduced, boat body 1
Since the groove 3 is not formed on the boat but the groove 3 is formed only on the ridge 2 and the notch is not directly provided on the boat body, the product strength is high,
Moreover, since the boat body 1 is thin, it is lightweight,
The heat capacity is also small, and a remarkable effect is obtained in practical use.

[Brief description of drawings]

FIG. 1 is a sectional view showing a cylindrical molded body before division processing for forming a boat for supporting a semiconductor wafer by the method of the present invention, and FIG. 2 is a sectional view showing the cylindrical molded body of FIG. 1 divided into three parts. FIG. 3 is a schematic perspective view showing a semiconductor wafer supporting boat manufactured by the method, FIG. 3 and FIG. 4 are schematic sectional views and perspective views showing a semiconductor wafer supporting boat manufactured by the invention of the present invention, respectively. 5 and 6 are views showing a conventional semiconductor wafer supporting boat. 1 …… Boat body 2 …… Ridge

Claims (3)

[Claims] 1. An SiC-based tubular body, in which four or more ridges are formed in parallel with each other in the longitudinal direction on the inner surface, is integrally molded,
The tubular body is cut at at least two locations along a plane that divides the ridge into two parts, and the obtained divided body includes at least three ridges including the divided ridges at both divided ends. A method for manufacturing a boat for supporting a semiconductor wafer, comprising forming a groove for supporting a wafer on each of the three or more ridges after the above division. 2. A method for manufacturing a boat for supporting a semiconductor wafer according to claim 1, wherein the main component is SiC-Si. 3. The method of manufacturing a boat for supporting a semiconductor wafer according to claim 1, wherein the CVD coating of SiC is formed after forming the groove.