JPS63178519A - Heat treatment equipment for semiconductor - Google Patents

Abstract

PURPOSE:To prevent the falling of a wafer due to the softening of a boat at the time of a high temperature by mounting a vertically movable base into a longitudinal cylindrical furnace body, hanging the boat on a strut on the base and maintaining the wafer into a holding groove in the boat in a stepped manner. CONSTITUTION:A connector 8 is engaged with a hook-shaped supporter 15 on the holder P side, using a semicylindrical cover 9 for the boat B as an outside surface, and the boat B is hung down from a holder P. Unified both B and P are turned by a shaft 12 at the lower end of the holder P by a motor M on thc outside of a furnace, and driven vertically by a shaft S and an arm A. The boat B in which wafers W are maintained is heated to 1000 deg.C or more in a furnace body 1. Since the boat B is suspended and supported to the holder P, it is not curved, and the slip-off and falling of the wafers W can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a vertical semiconductor heat treatment apparatus for heat treating semiconductor wafers.

(Prior Art) Horizontal furnaces have conventionally been widely used for heat treatment of semiconductors, but recently vertical furnaces as shown in FIG. 3 have also come to be used. The vertically arranged furnace body 1 is open at its lower end.

Inside the furnace body, a heater 2, a soaking tube 3, and a reaction tube 4 are built in at a predetermined interval, and a boat B carrying a semiconductor wafer W is placed from the lower end of the reaction tube to absorb heat from the furnace mouth. Place it on the boat table T which also serves as a table and insert it. In the vertical furnace configured in this way, the boat table T is initially located below the furnace body, and after the boat is placed, the drive shaft S is connected via the arm A.
is driven upwards and inserted into the furnace body, the state shown in the figure is reached, heating begins, and further processing gas is introduced. After the heat treatment is completed through a predetermined temperature process, the drive shaft is driven downward to lower the semiconductor wafer to a predetermined temperature, and then it is lowered from the table.

However, in the above-mentioned heat treatment equipment, when the temperature in the furnace exceeds 1000 degrees Celsius, the boat members become soft, and the weight of the semiconductor wafer deforms the boat support, causing the grooves carved in the support to break away. This results in the semiconductor wafer coming off.

Furthermore, when the boat is taken out of the furnace after the heat treatment is completed, the semiconductor wafers may be contaminated or the film thickness may vary depending on the temperature due to impurities contained in the atmosphere.

(Problems to be Solved by the Invention) As described above, there is a problem in that the boat is bent due to heat and the wafers come off.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a semiconductor heat processing apparatus that prevents wafers from falling off by preventing bowing of the boat due to heat.

[Structure of the invention]

(Means for Solving the Problems) A semiconductor heat treatment apparatus according to the present invention includes a cylindrical furnace body whose axis is vertically oriented, and is installed in the furnace body so as to be movable up and down, and is driven up and down by a drive mechanism. has a table with On this table, a support column with a hanging support provided on the upper part is integrally installed. Moreover, the boat is suspended by the support of this column.

This boat is provided vertically and has holding grooves for holding a plurality of wafers to be processed in a stacked manner. Further, the upper part has an engagement tool that engages with the suspension support, and the boat is suspended from the support of the column by this engagement tool.

(Function of the Invention) According to the present invention, even if the boat softens due to high temperature, a tensile load different from the conventional compressive load is applied to the boat, so that the boat does not bend significantly and can prevent wafers from falling off.

In addition, regarding contamination due to impurities, the semi-cylindrical structure overlaps at the ends, making it appear as if they were a single cylinder, which can prevent impurities from entering.

(Example) An example of the present invention will be described below with reference to FIGS. 1 and 2. Incidentally, the furnace body 1 itself is similar to the conventional device shown in FIG. 3, and corresponding parts are designated by the same reference numerals and explanation thereof will be omitted. Boat B has several columns 5 with grooves for placing semiconductor wafers W arranged side by side in a semicircular shape as shown in FIG. They are each fixed to the open semicircular plate 7. An engagement tool 8 for suspending the entire boat B is integrally provided on the semicircular plate 7 at the upper end.

Furthermore, a semi-cylindrical cover is provided around the outer periphery of the support column 5.

This semi-cylindrical cover 9 is installed so as to maintain a predetermined distance from the outer periphery of the semiconductor wafer W.

T is a table that is movable up and down in the vertically installed cylindrical furnace body 1, and has a drive shaft S.

It is driven up and down by a drive mechanism consisting of arm A. Note that M is a motor for rotating the table. This table T has a plurality of disks 10 connected at predetermined intervals by several supports 11, and has a shaft penetrating through the center in order to provide heat shielding at the furnace opening, which is another function. 1
2 is installed. Further, a semi-cylindrical support 13 is erected on the top disk lO. A hook-shaped support 15 for suspending the semi-circular plate 14 and the boat B is provided at the upper end of the semi-cylindrical support 13.

In the above configuration, in order to combine the boat B with the semi-cylindrical support column 13 of the holder P, the engagement tool 8 is attached to the hook-shaped support on the holder P side using the semi-cylindrical cover 9 of the boat B as the outer surface. The tool 15 is engaged with the tool 15 . Therefore, the boat B is suspended and fixed to the holder P. Both thus combined are rotated by a rotary drive motor M outside the furnace through a shaft 12 at the lower end of the holder P, and are driven up and down by a drive shaft S and an arm A.

Here, the boat B holding the wafers W is placed in the furnace body 1.
The members of boat B are heated to 000° C. or higher and soften.

In the conventional example shown in FIG. 3, the boat B is placed on the table T, so a compressive load is applied to the boat B due to the weight of the wafers W, etc., causing it to curve. On the other hand, the first
In the figure, since the boat B is suspended by the holder P, a compressive load is not applied to the boat B, but acts as an opposite tensile load. For this reason, boat B
The wafer W is not bent, and the wafer W can be prevented from coming off or falling off.

Further, since the wafer W is surrounded on the outer periphery by the semi-cylindrical cover 9 of the boat B and the semi-cylindrical support 13 of the holder P, even if the wafer W is taken out of the furnace body 1 after heat treatment, it cannot be exposed to the atmosphere. There is no contamination caused by impurities contained therein, and no variation in film thickness occurs.

Note that if contamination by impurities after heat treatment is not a problem, the boat B does not need to be provided with the semicylindrical cover 9. In this case, the support 13 of the holder P does not need to be semi-cylindrical either, and may be a simple support.

〔Effect of the invention〕

As described above, according to the present invention, the boat does not undergo curved deformation during heat treatment, and it is possible to prevent the semiconductor wafer from coming off or falling from the groove, increasing the amount of product retained, and contributing to improved productivity.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a semiconductor heat treatment apparatus according to the present invention, FIGS. 2(a) and 2(b) are a plan sectional view and an exploded perspective view of the boat shown in FIG. 1, and FIG. 3 is a conventional FIG. 2 is a cross-sectional view showing an outline of a vertical furnace. B...Boat T...Table W...Semiconductor wafer 1...Furnace body 2...Heater
8... Engagement tool 13... Support column 15...
Support agent Patent attorney Nori Chika Ken Yudo Hirofumi MitsumataFigure 3Figure 2

Claims (1)

[Claims] A cylindrical furnace body whose axis is vertically oriented; a table that is installed vertically movably inside the furnace body and driven vertically by a drive mechanism; and a table that is erected integrally on the table. It has a column with a support for hanging at the top, a holding groove provided in the vertical direction for holding a plurality of wafers to be processed in a stacked manner, and a support for hanging at the top. A semiconductor heat treatment apparatus comprising: a boat that has an engagement tool that engages with the support tool, and is suspended by the support tool of the column by the engagement tool.