JP2004333098A - Electric furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric furnace having a heat insulating material having no dust in view of an environmental issue wherein a heat insulating material has a dusting characteristic in a conventional electric furnace. <P>SOLUTION: An outer reflector 5 and an inner reflector 6 are arranged between an inner surface of a furnace wall and a heating element 3, a vacuum layer 7 is formed in an interior of the outer reflector 5, a side facing the inner reflector 6 is provided as a mirror finished surface, and a mounting angle of the inner reflector 6 is freely adjusted so that a reflecting direction of a heat ray from the heating element 3 can be changed. An air-cooled layer 8 is formed in the furnace wall, and a power terminal 14 of the heating element is taken out via the air-cooled layer 8 in the furnace wall. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electric furnace, and more particularly to an electric furnace suitable for heating a semiconductor.
[0002]
[Prior art]
In a conventional electric furnace, a heating element is arranged around an object to be heated, and a heat insulating material made of ceramic fiber is arranged around the heating element to reduce heat loss and suppress a rise in the temperature of the furnace outer wall. (Patent Document 1).
[0003]
[Patent Document 1]
JP-A-8-14764 (page 3, FIG. 1).
[0004]
[Problems to be solved by the invention]
However, in the conventional electric furnace, the heat insulating material has a dust generating property, and an electric furnace having a heat insulating material free from dust has been required due to environmental problems. SUMMARY OF THE INVENTION The present invention has been made to solve the problems described above, improve the heat radiation characteristics of a heating element, and aim at uniform heating.
[0005]
[Means for Solving the Problems]
The electric furnace of the present invention comprises a furnace wall, an outer reflector, an inner reflector, and a heating element which are sequentially arranged from the furnace wall toward the core, and the outer reflector has a vacuum layer inside. The side facing the inner reflector is a mirror surface, and the orientation of the inner reflector with respect to the core is variable.
[0006]
The heating element is a lamp heater in which a high-resistance heating element such as tungsten or carbon is sealed in a heat-resistant material tube.
[0007]
Further, the power supply terminal of the heating element has a pin-socket structure.
[0008]
Further, the furnace wall has an air-cooling layer, and a power terminal of the heating element is cooled by the air-cooling layer.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0010]
In FIG. 1, reference numeral 1 denotes a cylindrical furnace wall of an electric furnace, 2 denotes an object to be heated such as a wafer arranged in the center of the furnace, and 3 denotes a plurality of, for example, eight objects surrounding the object to be heated and arranged in the furnace. Numeral 4 denotes a terminal box provided on the outer peripheral surface of the furnace wall 1.
[0011]
In the present invention, an outer reflector 5 and an inner reflector 6 are arranged between the inner surface of the furnace wall 1 and the heating element 3.
[0012]
The outer reflector 5 has a vacuum layer 7 formed therein, the side 5a facing the inner reflector 6 has a mirror surface, and the inner reflector 6 has a mounting angle that can change the direction of reflection of heat rays from the heating element 3. Can be adjusted freely.
[0013]
Further, an air cooling layer 8 is formed in the furnace wall 1, cooling air is introduced into the air cooling layer 8 via an introduction pipe 9, and the cooling air is led to the outside via an extraction pipe 10.
[0014]
The heating element 3 is, for example, a lamp heater in which a high resistance heating member 3a such as tungsten or carbon is sealed in a heat resistant material tube 3b such as a quartz tube or a ceramic tube as shown in FIG.
[0015]
The lead wire 11 of the heat generating member 3a has a pin 12 at the tip, and is connected to a power supply pin socket 14 in the terminal box 4 through a hole 13 provided in the outer reflector 5 and an air cooling layer 8 to be connected to a vacuum terminal. Structure.
[0016]
【The invention's effect】
Since the electric furnace of the present invention has the above-described configuration, the following effects can be obtained.
[0017]
1) By appropriately adjusting the angle of the inner reflector, the object to be heated can be focused, and the efficiency of heating the object to be heated can be increased.
[0018]
2) Since the outer and inner reflectors are provided around the heating element, the radiant energy leaked from the reflector is returned to the object to be heated by the outer reflector without being emitted to the outside, so that the thermal efficiency to the object to be heated is further improved. Further improve.
[0019]
3) Since the outer reflective plate has a mirror-surface vacuum structure, the heat insulating property is excellent, and a heat insulating material is not required. As a result, heat loss is reduced and the cost is reduced.
[0020]
4) If the heating element is a lamp heater and can be replaced, the life of the electric furnace can be extended.
[0021]
5) Clean because it does not use a heat insulating material (heat insulating material) made of ceramic fiber, which is preferable in terms of environment and safety.
[0022]
6) If the power terminal of the lamp heater is of the pin-socket type, the heating element can be replaced with one touch.
[0023]
7) If the air-cooling layer is provided in the furnace wall and the power terminal of the heating element is taken out through the air-cooling layer, the life of the power terminal can be extended.
[Brief description of the drawings]
FIG. 1 is a cross-sectional plan view of an electric furnace of the present invention.
FIG. 2 is a detailed view of the heating element shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cylindrical furnace wall 2 Heated object 3 Heating element 3a High resistance heating member 3b Heat resistant material tube 4 Terminal box 5 Outer reflector 5a Side facing inner reflector 6 Inner reflector 7 Vacuum layer 8 Air cooling layer 9 Introducing pipe 10 Outgoing pipe 11 Lead wire 12 Pin 13 Hole 14 Power supply pin socket

Claims (4)

A furnace wall, comprising an outer reflector, an inner reflector, and a heating element sequentially disposed from the furnace wall toward the core, the outer reflector having a vacuum layer therein, and having an inner reflector. An electric furnace wherein the side facing the surface is a mirror surface, and the direction of the inner reflector with respect to the core is variable. 2. The electric furnace according to claim 1, wherein the heating element is a lamp heater in which a high-resistance heating element such as tungsten or carbon is sealed in a heat-resistant material tube. 3. The electric furnace according to claim 1, wherein a power terminal of the heating element has a pin-socket structure. 4. The electric furnace according to claim 1, wherein the furnace wall has an air cooling layer, and a power terminal of the heating element is cooled by the air cooling layer.

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