JP2006269503A - Method for manufacturing silica glass wafer boat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a silica glass wafer boat in which no posts are deformed in the annealing process of the silica glass wafer boat. <P>SOLUTION: The method comprises a process where the first planar body of the wafer boat projects from a hollow body and a supporting means is interposed so that it comes into contact with the upper end of the hollow body and the first planar body, for the wafer boat and a silica glass tube placed on the stand plate of a furnace, for eliminating distortion at the welded section of the wafer boat; and a process for storing the wafer boat and the silica glass tube in the annealing furnace for annealing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a silica glass wafer boat, and more particularly to a method for manufacturing a silica glass wafer boat with an improved annealing process of the boat.

  In general, a wafer boat is used for high-temperature processing of semiconductor wafers. This wafer boat is formed by attaching three or four support columns provided with a large number of support grooves to the first plate and the second plate, and the material used is highly pure and highly viscous at high temperatures. Silica glass is often used because of the above.

  Moreover, the manufacturing method of a silica glass vertical wafer boat produces the 1st plate-like body and the 2nd plate-like body, produces 3 or 4 support | pillars, and these support | pillars are made into the 1st plate-like form. And the second plate-like body are welded, and the support groove is formed by grooving the support column. Further, the support groove is annealed by a burner, and the entire wafer boat is polished in order to remove the distortion of the welded portion. Out.

  Distortion is performed by placing the wafer boat horizontally on the base plate of the furnace (with the support rod horizontally), storing it in the annealing furnace, and annealing it. Various methods are used to prevent thermal deformation of the column. This jig is used. However, even if such a jig is used, it is difficult to increase the flatness because the base plate is also required to increase in size as the wafer boat becomes longer, and such a low flatness is difficult. When the base plate is used, the support column is deformed due to this flatness, and even when a high flat base plate is used, sufficient deformation countermeasures are not realized.

As for annealing of the wafer boat, there is a method described in Patent Document 1.
JP-A-8-78349

  The present invention has been made in consideration of the above-described circumstances, and an object thereof is to provide a method for manufacturing a silica glass wafer boat in which a support column is not deformed during an annealing process of the silica glass wafer boat.

  In order to achieve the above-described object, a method for producing a silica glass wafer boat according to the present invention includes a step of producing a first plate-like body, a second plate-like body and a column made of silica glass, A step of assembling a wafer boat by welding to the first plate-like body and the second plate-like body, a step of forming a support groove in the support column of the assembled wafer boat, and a step of polishing the support groove And an annealing process for annealing the entire wafer boat in order to take the distortion of the welded portion of the wafer boat, and the annealing process is performed on the base plate so that the first plate-like body faces upward. A step of disposing a boat and disposing a hollow body so as to surround the outer periphery; a step of interposing a support means so as to contact the lower surface of the first plate-like body and the upper end portion of the hollow body; The The Haboto and the hollow body is housed in an annealing furnace, characterized by having a step of annealing.

  Preferably, the support means includes a support plate placed on an upper end portion of the hollow body and provided with a screw hole, and a screw screwed into the screw hole and having a tip abutting on the top plate.

  According to the method for manufacturing a silica glass wafer boat according to the present invention, it is possible to provide a method for manufacturing a silica glass wafer boat in which the support column is not deformed during the annealing step of the silica glass wafer boat.

  Hereinafter, an embodiment of a method for producing a silica glass wafer boat according to the present invention will be described by taking a vertical silica glass wafer boat as an example with reference to the accompanying drawings.

  FIG. 1 is a perspective view of a vertical silica glass wafer boat manufactured by the method of manufacturing a silica glass wafer boat according to the present invention, and FIG. 2 is a manufacturing process diagram of the manufacturing method of the vertical silica glass wafer boat.

  As shown in FIG. 1, the vertical silica glass wafer boat 1 manufactured using the manufacturing method according to the present invention is made of silica glass having high viscosity at high purity and high temperature, and is used as a second plate-like body. The disc-shaped bottom plate 2 and three support posts 4 are erected so that the wafer insertion port 3 is formed in the bottom plate 2, and a circle as a first plate-like body is formed at the upper end of the support post 4. A plate-like top plate 5 is formed.

  Each of the support columns 4 is provided with a plate-like support surface 6 that has the same shape and supports a large number of semiconductor wafers and has a rectangular shape in plan view, and a large number of support grooves 7 formed on the support surface 6. .

  The wafer boat 1 having such a structure is manufactured by a process as shown in FIG.

  As shown in FIG.1 and FIG.2, the baseplate 2, the top plate 5, and the three support | pillars 4 are produced from a silica glass member (P1).

  Further, the support column 4 is welded to the bottom plate 2 and the top plate 5 using a flame (P2).

  Grooves are made on the support 4 of the assembled wafer boat 1 using a grooving device to form support grooves 7, and the support grooves 7 are polished with a burner (P3).

  Thereafter, the entire wafer boat 1 is annealed to remove the distortion of the welded portion at P2 (P4).

  This overall annealing step P4 is performed along the flow shown in FIG. 3 as follows.

  As shown in FIG. 4, for example, the wafer boat 1 is placed on a base plate 11 that forms a lower furnace lid of the furnace, and the height of the wafer boat 1 is slightly lower than the height of the wafer boat 1. Is slightly larger than the diameter of the hollow body, that is, a hollow body in which the wafer boat can be inserted and the operation through hole 12b is provided in the vicinity of the upper end portion 12a, preferably a silica glass tube 12, is loosely fitted to the wafer boat 1, It is mounted on the base plate 11 (P41).

  At this time, the top plate 5 protrudes from the silica glass tube 12, and a gap G is formed between the upper end portion 12 a of the silica glass tube 12 and the top plate 5.

  As shown in FIGS. 5 and 6, the support plate 13 provided with one screw hole 13 a and the support plate 14 provided with two screw holes 14 a are attached to the column 4 by using the gap G. It is placed on the upper end 12a in a parallel state so as not to contact.

  As shown in FIG. 7, the operator then puts his / her hand into the silica glass tube 12 using the operation through hole 12b, and the silica glass screw 15 as a support means is screwed into the screw holes 13a and 14a. Then, the screw 15 is turned until the tip 15a of the screw 15 contacts the top plate 5 (P42).

  In the present embodiment, the support means in the present invention is formed by a support plate provided with a screw hole and a screw screwed into the screw hole and having an upper end abutting the top plate. The screw is preferably provided with a locking mechanism.

  As shown in FIGS. 8 and 9, the wafer boat 1 and the silica glass tube 12 are accommodated in an annealing furnace in a state where the supporting means is used, that is, the screw 15 is in contact with the top plate 5, and 500 to 500 in an atmospheric atmosphere. Annealing is performed at 800 ° C. for 30 minutes and at 1100 to 1200 ° C. for 30 minutes to remove the distortion of the welded portion, and the temperature is lowered to room temperature (P43).

  In this annealing process, the wafer boat 1 is subject to deformation of the support column 4 exposed to high temperature, but the top plate 5 is supported by the silica glass tube 12 via the screws 15 and the support plates 13 and 14. Deformation of the column 4 welded to 5 is prevented. At this time, it is preferable to set the supporting means to about 10 to 15% of the load of the wafer boat supported by the supporting means via the top plate.

  Since the support plates 13 and 14 and the screw 15 are made of the same material as that of the wafer boat 1 as in the case of the silica glass tube, the thermal expansion coefficient is the same, the deformation of the support column 4 is more effectively prevented, The wafer boat 1 is not contaminated by impurities.

  In this embodiment, the silica glass tube has been described as an example of a single long tube. However, as shown in FIG. 10, the silica glass tube 22 is interposed through support plates 13 and 14 similar to the above support plate. Two to three silica glass tubes 22 may be stacked and lengthened.

  As shown in FIG. 11, the support means in the present invention is formed by laminating a plurality of silica glass plates 23, and the top plate 5 is supported via the laminated silica glass plates 23. Good.

  Moreover, in the said embodiment, although the case where the silica glass tube was used as a hollow body was demonstrated, it is not restricted to this, A horizontal cross section can use various cross-sectional shapes, such as a rectangle or an ellipse. Furthermore, the present invention can be applied to the manufacture of horizontal wafer boats as well as vertical wafer boats.

  According to the manufacturing method of the vertical silica glass wafer boat of this embodiment, the manufacturing method of the vertical silica glass wafer boat which does not deform | transform a support | pillar at the time of the annealing process of a wafer boat is implement | achieved.

The perspective view of the wafer boat manufactured by the wafer boat manufacturing method of the present invention. The wafer boat manufacturing process figure of this invention. The annealing process figure of the wafer boat manufacturing method of this invention. The longitudinal cross-sectional view of the loosely-fitted state of the wafer boat and the silica glass tube in the annealing process of the wafer boat manufacturing method of the present invention. The top view of the support plate mounting state in FIG. The longitudinal cross-sectional view of the support plate mounting state in FIG. Explanatory drawing of the screwing method of the screw in the annealing process of the wafer boat manufacturing method of this invention. The top view which shows the top plate support state by the screw in the annealing process of the wafer boat manufacturing method of this invention. The longitudinal cross-sectional view which shows the top-plate support state by the screw in the annealing process of the wafer boat manufacturing method of this invention. The longitudinal cross-sectional view of the loose fitting state of the wafer boat of another embodiment in the annealing process of the wafer boat manufacturing method of this invention, and a silica glass tube. The side view of other embodiment of the support plate mounting state in FIG.

Explanation of symbols

1 Vertical silica glass wafer boat 2 Bottom plate (second plate)
3 Wafer insertion slot 4 Post 5 Top plate (first plate)
6 Support surface 7 Support groove 11 Base plate 12 Silica glass tube 12a Upper end portion 12b Operation through hole 13 Support plate 13a Screw hole 14 Support plate 14a Screw hole 15 Screw 15a Tip

Claims (2)

Producing a first plate, a second plate and a column made of silica glass;
Welding the column to the first plate and the second plate and assembling a wafer boat; forming a support groove in the column of the assembled wafer boat;
In order to take the distortion of the welded portion of the wafer boat and the step of polishing the support groove, the wafer boat has an annealing step for annealing the whole wafer boat. The wafer boat is disposed on the base plate so that the outer periphery is disposed, and a hollow body is disposed so as to surround the outer periphery, and a supporting means is interposed so as to contact the lower surface of the first plate body and the upper end of the hollow body. And a step of accommodating the base plate, the wafer boat, and the hollow body in an annealing furnace and annealing them. The support means includes a support plate placed on an upper end portion of the hollow body and provided with a screw hole, and a screw screwed into the screw hole and having a tip abutting on the top plate. 2. A method for producing a silica glass wafer boat according to 1.

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