JPS60251616A - Furnace core tube device - Google Patents

Abstract

PURPOSE:To produce a furnace core tube device easy to fix and remove a cap without any gas leakage by a method wherein a heat resisting flexible body fixed along the periphery of fixing wall like a continuous ring is pressurized by fluid running through a fluid channel to expand filling the gap between the furnace core tube and the edge thereof. CONSTITUTION:A heat resisting flexible body 18 is fixed inside the edge 15 of cap 15 like a ring covering the edge 15. As for a fixing process, the heat resisting flexible body 18 is formed into a band type ring and the end of body 18 is bonded inside the edge 15 so that the band may cover an opening 17. Said body 18 may be made of silicon rubber or heat resisting rubber etc. to be expanded at the central part thereof by the gas running through a gas channel 11. A furnace core tube 3 adhers closely to the part 4 near a wafer inlet to be sealed up by the expansion. In such a status, any gas sucked from a gas introducing chennal 2 may be forced to be discharged from a gas discharging channel 13 only.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a furnace core tube device, and more specifically, the present invention relates to a furnace core tube device, and more specifically, when heating a semiconductor wafer or diffusing impurities therein, toxic gas or flammable gas is generated. This invention relates to a furnace core tube device that uses gas.

(Prior Art) With the advancement of manufacturing technology for ICs, LSIs, etc., various treatments are being performed during their manufacturing. In the wafer processing stage, especially the heating stage, to manufacture these, H2
, flammable gases such as SiH4, F, PH3, HC
Toxic gases such as l are increasingly being used.

Conventionally, furnace core tube devices that use such flammable gases or toxic gases are similar to the device described in Japanese Patent Publication No. 52-7793 or the device for carrying out the method of Japanese Patent Publication No. 51-44373. The furnace core tube has a furnace core tube and a cap, and the cap fits tightly into the vicinity of the wafer insertion port of the furnace core tube, and the gas exhaust passage leads out from the cap at the end of the furnace core tube. It is configured so that the gas introduced from the gas introduction passage is discharged.

However, since both the furnace core tube and the cap are made of quartz glass, which is a hard material, and the fitting portions are ground glass-like, it is difficult to fit them exactly. Further, since the cap is tightly fitted, removing the fitted cap is as difficult as when fitting the cap. In addition, if the furnace core tube and cap collide with each other during fitting or removal, they may be destroyed, and even if not so severe, cracks and chips are likely to occur. was there.

Conventional heating furnaces have the above-mentioned drawbacks, and therefore, when manually fitting and removing the cap, great care is required, which is troublesome. In addition, when trying to fit the cap to the furnace core tube using an automatic device, a new problem arises that requires an extremely complicated control system to overcome the drawbacks mentioned above. The attempt almost ended in failure.

(Object of the Invention) The present invention was made in order to solve the above-mentioned drawbacks, and aims to provide a furnace core tube device in which the cap can be easily fitted and removed, and there is no gas leakage. purpose.

(Structure of the Invention) The present invention has been made to achieve the above-mentioned objects. In the furnace core tube apparatus, the furnace core tube apparatus includes a cap capable of closing the wafer insertion port, a passage for introducing gas into the furnace core tube, and a passage for discharging gas from the inside of the furnace core tube. A fluid communication body communicating from the outside of the cap to the fitting wall of the edge with the furnace core tube, and a heat-resistant flexible body attached in a continuous annular shape along the peripheral wall of the fitting wall of the previous recording, the flexible body is a furnace core tube device configured to expand in response to the pressure of fluid transmitted from the fluid passage to close the gap between the furnace core tube and the edge.

(Embodiment) FIG. 1 is a sectional view for explaining a preferred embodiment of the present invention.

In the figure, the furnace core tube device includes a furnace core tube 3 having a gas introduction passage 2 similar to the conventional one, a cap 12 having a gas passage 11 inside, and a cap 12 having a gas discharge passage 13 inside. It consists of a push rod 14 fixed inside the. The cap 12 is preferably attached to an automatic device (not shown) for moving the gap 12 in the direction of the arrow to close or open the wafer insertion port. push rod 14
moves in the direction of the arrow along with the cap.

The diameter of the cap 12 near the wafer insertion opening 40 of the furnace core tube 3 is formed slightly larger. This is because this prevents the edge 15 of the cap 12 from colliding with the portion 4 near the wafer insertion port, and makes it easier to fit and remove the cap 12 with the portion 4 near the wafer insertion port. be. The gas passage 1 inside the cap 12 is formed in the shape of a tunnel from the connecting pipe 16a projecting to the outside of the cap 12 into the cap 12, and is connected to the inside of the edge 15, that is, the cap 12.
It communicates with the opening 17 of the fitting wall. The gas passage 11 is formed so as to be routed from the center of the gap 12, that is, from the connecting pipe 16a. Since I-manufacturing is difficult, it is preferable to connect it to the connecting pipe 16b or 16c shown by the imaginary line. In particular, in the case of 16c, the hole extends from this point through the edge 15, making manufacturing very easy. In addition, when using the connecting tube 16a, it may be formed in a shape such that the edge 15 is attached to a parallel flat plate whose ends are sealed.

A ring-shaped heat-resistant flexible body 18 is attached to the inside of the edge 15 of the cap 12 so as to cover the edge 15. As for the mounting method, it is preferable to form the heat-resistant flexible body 7B into a band-shaped ring and adhere the end portion to the inside of the edge 15 so that the band covers the aperture 17. Further, it is preferable that the heat-resistant flexible body 18 is bonded so that there is a slack in the center as shown in the cross-sectional view. The reason is connecting pipe 16
A heat-resistant flexible body 18 is formed inside the edge 15 when expanded by gas sent from a compressor etc. connected to the
This is to make the central part of the holder protrude. Heat resistant flexible body 1
For step 8, use a silicone comb or a heat-resistant comb.

A push rod 14 is provided near the center of the cap 12 so as to pass therethrough along the moving direction of the cap 12. The push rod 14 has a hook 19 formed on the inner end of the cap 12 for hooking a diffusion boat. Due to the presence of this hook 19, the boat carrying the semiconductor wafers can be moved within the furnace core tube 3 along with the movement of the cap 12. A gas discharge passage 13 is provided in the push rod 14.
A connecting pipe 2 formed on the outside of the cap 12
Connected to 0.

In addition to being formed in the push rod 14, the gas exhaust passage 13 may be provided in the furnace core tube 3 or in the cap 12.

FIG. 2 is a sectional view showing how the heating furnace described above is used. In the figure, a pipe is connected to each connecting pipe.

The center portion of the heat-resistant flexible body 18 expands due to the gas sent through the gas passage 11. Due to the expansion, it comes into close contact with the wafer insertion port vicinity portion 4 to seal the furnace core tube 3. In this state, the gas sucked in from the gas introduction passage 2 is no longer discharged from any route other than the gas discharge passage 13. The gas pressure in the gas passage 1 for this purpose may be 2 to 3 atm, and may be air sent from a compressor device.

Incidentally, since the furnace core tube 3 is sealed by such an action, what is present in the gas passage 11 and transmits pressure to the heat-resistant flexible body 18 may be a liquid, for example, oil. In other words, it may be any fluid as long as it transmits pressure.

When the heater 2 is operating, the temperature inside the furnace core tube 3 will be around 1000°C, but if the heater 2 is kept away from the wafer insertion port vicinity 4, it will be difficult for the furnace core tube 3 to conduct heat. The temperature here is 100° C. or lower, so there is no problem in using silicone rubber or a heat-resistant comb 8 as the heat-resistant flexible body 18. These rubbers are 100
This is because it can withstand temperatures of ℃ or higher.

The heat-resistant flexible body 18 preferably has such elasticity that when the cap 12 is exposed to soot and the gas passageway 110 atmosphere is reduced, it deflates and loses contact with the wafer insertion opening 4.

Although the preferred embodiment has been described above using an example in which the push rod 14 is provided so that the boat carrying the semiconductor wafer can be moved as the cap 12 moves, the present invention does not have this push rod 14. Needless to say, it can also be applied to cases. Further, the cap used in the present invention may be of a type that is inserted into the furnace core tube, for example, like a cork stopper.

In this case, the fitting wall of the cap is the outer side surface of the cap, and the heat-resistant flexible body is attached thereto.

(Effects of the Invention) As explained above, in the present invention, ■ Since the furnace core tube and the cap are loosely fitted, it is easy to fit and remove the cap, and it can be done automatically without the need for a complicated control system. The fitting and removal of the furnace core tube and cap may be easy. ■ The heat-resistant flexible body attached to the fitting wall of the cap due to the pressure of the gas introduced into the gas passage. Since the furnace core tube can be sealed, it is possible to use a pestle for home use. Furthermore, the flexible body attached to the fitting wall of the cap acts as a cushion between the furnace core tube and the cap, so there is no impact when fitting or removing the cap. 9. No cracks or chips will occur in the cap or furnace core tube.

[Brief explanation of the drawing]

FIG. 1 is a sectional view for explaining a preferred embodiment of the present invention,
FIG. 2 is a sectional view for explaining its usage. J...Heating furnace, 2...Gas introduction passage, 3...Furnace core tube, 4...Wafer insertion port vicinity, II...Gas passage, 12...Ca Jf113...Gas Discharge passage, 1
4... Push rod, 15... Edge, 17... Opening part, 1
8...Heat-resistant flexible pull body, 19...Hook. Patent applicant Oki Electric Industry Co., Ltd.

Claims (1)

[Claims] a furnace core tube having a wafer insertion port; a cap having a cylindrical edge that loosely fits into the furnace core tube and capable of closing the wafer insertion port; and a passageway for introducing gas into the furnace core tube; In the furnace core tube device, the cap includes a fluid passage leading from the outside of the cap to a fitting wall of the edge with the furnace core tube, and a fitting wall of the edge. It has a heat-resistant flexible body attached in a continuous annular shape along the circumferential wall of the joint wall, and the flexible body expands under the pressure of the fluid transmitted from the fluid passage and connects to the furnace core tube. Furnace tube device configured to close the gap between the