JPH0311623A - Furnace tube for heat treatment of semiconductor - Google Patents

Abstract

PURPOSE:To enable accurate and simple measurement of a temperature in the vicinity of a wafer setting section by providing a thermocouple insertion pipe separately from a gas introduction pipe, by inserting thereinto a thermocouple together with a thermocouple protection pipe and by providing a number of heat-radiating fins outside the insertion pipe. CONSTITUTION:A thermocouple insertion pipe 15 is provided near a gas introduction pipe 9, and a number of heat-radiating (cooling) fins 16 are provided outside the middle part thereof, while a thermocouple protection pipe 19 is inserted inside the thermocouple insertion pipe 15. By inserting a thermocouple into the thermocouple protection pipe 19, a temperature in close vicinity to wafers 33 can be measured. Thereby the temperature can be measured accurately as occasion calls, the temperature of a flange part is lowered by the heat- radiating function of the fins, and excellent airtightness is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a furnace core tube for semiconductor heat treatment, and in particular relates to improvements in the attachment of thermocouples.

Conventional technology: The degree of integration of semiconductor manufacturing elements has increased from 64KB to 256KB to IM.
As the size increases from B to 4MB, highly accurate temperature control during heat treatment is required. Therefore, it is required not only to measure the temperature inside the furnace with no wafer inserted, but also to measure the temperature inside the furnace with the wafer inserted.

Therefore, attempts have been made to achieve more precise temperature control by inserting a thermocouple from the entrance/exit of the wafer loading boat in the furnace core tube.

Problems to be Solved by the Invention However, inserting a thermocouple through the inlet/outlet portion of the wafer loading boat in the furnace core tube is a complicated operation, and a method for easily and accurately measuring temperature has not been desired.

Purpose of the Invention In view of the problems of the prior art, the present invention provides a method for accurately and easily measuring the temperature near the wafer installation part inside the furnace core tube by inserting a wafer into the furnace core tube and inserting a thermocouple. SUMMARY OF THE PATENT INVENTION Which is characterized by providing a furnace core tube for semiconductor heat treatment that can achieve the above-mentioned object.In order to achieve the above-mentioned object, the present invention has a core tube for semiconductor heat treatment as set forth in claim 1.

Means for Solving the Problems The furnace core tube for semiconductor heat treatment of the present invention is a furnace core tube having a gas introduction tube, and a thermocouple insertion tube is provided separately from the gas introduction tube, and the thermocouple is inserted therein together with a thermocouple protection tube. The thermocouple is inserted into the thermocouple insertion tube, and a large number of heat radiation fins are provided on the outside of the thermocouple insertion tube.

The materials of the furnace core tube, thermocouple protection tube, and fins are all made of quartz glass, SiC-impregnated SiC, self-sintered SiC, and the like. In particular, those made of Si-impregnated SiC or self-sintered SiC can be used at higher temperatures of 1200° C. or higher than quartz glass.

The thermocouple protection tube is supported by being inserted into the thermocouple insertion tube.

The radiation fins are provided integrally with, fitted with, or bonded to the thermocouple insertion tube.

It is desirable that the diameter of the radiation fin is at least 1.5 times the diameter of the thermocouple insertion tube. If it is less than 1.5 times, a sufficient cooling effect cannot be obtained. Further, it is desirable that the pitch of the radiation fins is 10 mm or more. If it is less than 10 mm, they will interfere with each other and a sufficient cooling effect cannot be obtained.

Effect: By installing a thermocouple using a thermocouple insertion tube, the temperature near the wafer installation part in the furnace core tube can be accurately measured at any time with the wafer inserted.

Further, the temperature at the end of the thermocouple insertion tube can be lowered by the heat radiation effect of the radiation fins provided on the outside of the thermocouple insertion tube, and it is possible to perform sealing using, for example, an O-ring made of Teflon. Therefore, good airtightness can be obtained.

Embodiments Hereinafter, embodiments of the furnace core tube for semiconductor heat treatment according to the present invention will be described with reference to the drawings.

FIG. 1 is a top view of the furnace core tube 10. The furnace core tube 10 has a gas introduction part 12 at one end and a gas exhaust part 1 at the opposite end.
1. Consists of a soaking section located between these ends.

The exhaust section 11 usually has a few grooves, into which the exhaust cap 20 is fitted. The exhaust cap 20 has an exhaust pipe 23, and the end of the exhaust pipe 23 is provided with a flange 21.

In addition, there are many heat radiation (cooling) fins 22 on the outside of the exhaust pipe.
is the provision. The configuration is such that the exhaust canister knob 20 is removed and the semiconductor wafer 1 is installed.

A gas introduction pipe 9 is provided in the center of the gas introduction section 12. A flange 13 is formed at the end of the gas introduction pipe.

Further, a large number of heat radiation fins 14 are provided on the outside of the gas introduction pipe.

A thermocouple insertion tube 15 is provided near the gas introduction tube 9. FIG. 2 is an end view of the furnace core tube, showing the arrangement of the thermocouple insertion tube 15.

The thermocouple insertion tube 15 will be explained in detail with reference to FIG. The thermocouple insertion tube 15 has a cylindrical shape as a whole, and a flange 17 is provided at the end. Further, a large number of heat radiation (cooling) fins 16 are provided on the outside of the intermediate portion of the thermocouple insertion tube 15. The fins 16 are disc-shaped. The fins 16 may be constructed integrally with the thermocouple insertion tube 15, or may be made separately and then fitted or bonded together.

The same applies to the flange 17.

See Figure 3. Thermocouple protection tube 19 is thermocouple insertion tube 1
It is inserted inside 5. The thermocouple protection tube 1.9 prevents the thermocouple from contaminating the inside of the furnace and also serves to protect the thermocouple (not shown) installed therein. Thermocouple protection tube 1
9 has an overall cylindrical shape with one end sealed, and has a flange 24 at one end.

A Teflon O-ring is installed between the flange 17 of the thermocouple insertion tube 15 and the flange 24 of the thermocouple protection tube 19 to improve airtightness. The two are connected, for example, by screwing.

Please refer to FIG. In FIG. 4, a furnace core tube 10 is installed in a furnace body 32, and a heater 31 is installed around the furnace core tube 10. Inside the furnace core tube 10 is a wafer loading jig 3.
The wafer 33 is installed through the wafer 0. By inserting a thermocouple (not shown) into thermocouple protection tube 19, the temperature in the immediate vicinity of wafer 33 can be measured. In this embodiment, thermocouple protection tubes 19 are arranged below the wafer 33 diagonally to the left and right.

However, by providing the thermocouple insertion tube in a different position,
It is clear that the protective tube 19 can be arranged in other positions.

The furnace core tube, thermocouple protection tube, and fins were made of Si-impregnated SiC.

Please refer to FIG. In FIG. 5, the wafer 33 is the furnace core tube 10.
Even if the thermocouple insertion tube 1 is not located in the center of
5 at the top, the temperature in the immediate vicinity of the wafer 33 can be measured with the wafer 33 inserted.

Please refer to FIG. FIG. 6 shows an example in which a wafer 33 is installed via a wafer loading jig 34.

Next, an experiment was conducted to determine the temperature of the flange portion and the presence or absence of gas leakage when the furnace core tube was used, in the case where the thermocouple insertion tube 15 was not provided with radiation fins and when it was provided with radiation fins. The results are shown in Table 1. As a result, it was found that when fins were not provided, the temperature at the flange was high and gas leakage occurred. When fins are provided, the temperature of the flange portion decreases due to the heat dissipation effect of the fins, and good airtightness can be obtained.

Note that the present invention is not limited to the above-described embodiments. For example, only one thermocouple insertion tube may be provided, or three or more thermocouple insertion tubes may be provided. Further, the installation location is not limited to the vicinity of the gas introduction pipe, but may be installed at other locations such as an exhaust cap.

Furthermore, the shape and number of fins can be freely set.

[Brief explanation of the drawing]

FIG. 1 is a top view showing an embodiment of the furnace core tube for semiconductor heat treatment according to the present invention, FIG. 2 is an end view of the furnace core tube for semiconductor heat treatment,
Figure 3 is an enlarged partially cross-sectional view showing the thermocouple insertion tube;
FIG. 4, FIG. 5, and FIG. 6 are cross-sectional views of each embodiment showing a furnace core tube in which a wafer is installed. 9... Gas introduction pipe 10... Furnace core tube 15... Thermocouple insertion pipe 16... Fin agent person

Claims (1)

[Scope of Claims] A furnace core tube for semiconductor heat treatment, characterized by having a structure in which a thermocouple insertion tube is provided and a thermocouple is inserted therein, and a large number of radiation fins are provided on the outside of the thermocouple insertion tube.