JPH07183238A - Heating device - Google Patents

Abstract

PURPOSE:To improve the heating efficiency of a heating device by using a piece constructed in such a way that the heat storing amount of the piece which supports heating element wires passed through the piece can be reduced and the quantity of heat radiation from the piece can be increased by minimizing the heating surface shielding areas of element wires by the piece. CONSTITUTION:A piece which is the supporting body 4 of heating element wires 3 is constituted in such a way that the piece is tapered (in a trapezoidal shape, triangular shape, inverted-T shape, etc.) toward an object to be heated and the areas of the element wires 3 shielded by the internal surfaces of the holes 6 of the supporting body 4 for passing the element wires 3 are made smaller so as to increase the area of heat radiation against the object to be heated. In addition, the mass of the supporting body 4 is reduced so as to reduce the heat storing amount of the body 4. Therefore, the heating efficiencies of various kinds of thermal reaction furnaces used in a semiconductor manufacturing process can be improved remarkably.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film manufacturing apparatus used in a semiconductor manufacturing process, a heating apparatus having a structure suitable for heating various thermal reaction furnaces such as an impurity diffusion furnace or an oxidation furnace to a predetermined temperature. Regarding

[0002]

2. Description of the Related Art As a heating device for an impurity diffusion furnace or an oxidation furnace for forming a thermal oxide film, which is used in a conventional semiconductor manufacturing process, for example, one having a structure shown in FIG. 5 is generally used. . As shown in FIG. 6 (enlarged view of portion B in FIG. 5), a wire support (piece) 5 that supports a heating element (heater) wire 3 spirally wound in a multi-stage annular shape is shown in FIG. The piece 5 penetrating and supporting the heater element wire 3 had a rectangular parallelepiped shape with a predetermined width a, depth d, and height L. For this reason, in the case of a heating device used at a high temperature, for example, 1000 ° C. or higher, the heater wire 3 may soften and drip due to heat. Therefore, the number of pieces 5 or the row of support of the heater wire 3 is increased. As a result, a method of preventing the heater wire from sagging has been adopted. However, if the number of pieces 5 or the support rows of the pieces 5 is increased so as to withstand a high temperature, the heating capacity is increased by the increased number of the pieces 5, and the heating surface of the heater wire 3 passes through the wire of the piece 5. Hole 6
There is a problem that the area covered by the inner wall of the is increased, the heat radiation amount of the heating element in that part is reduced, and the heating efficiency is reduced.

[0003]

As described above, the heating device used in the conventional impurity diffusion furnace or the oxidation reaction furnace for forming a thermal oxide film in the semiconductor manufacturing process is the heater element wire which is a heating element. Since the shape of the piece (element wire support) that penetrates and supports the heater element is a rectangular parallelepiped having a predetermined width in the longitudinal direction of the heater element wire, the number or piece row of pieces supporting the heater element wire, or the heater element wire As the number of spiral windings increases, the amount of heat storage increases due to the increase in the number of pieces, and the area where the heating surface of the heater wire is shielded by the inner wall surface of the hole of the piece that penetrates and supports increases. However, there is a problem of heat loss that the heat radiation amount of the heater wire is reduced by that amount and the heating efficiency is reduced.

An object of the present invention is to solve the above problems in the prior art, reduce the amount of heat stored in the piece supporting the heater wire, and reduce the shielding area of the heating surface of the heater wire by the piece as much as possible. An object of the present invention is to provide a heating device for a vertical reactor having a good heating efficiency, which uses a piece having a structure capable of suppressing a decrease in heat radiation amount (heat loss).

[0005]

In order to achieve the above-mentioned object of the present invention, a manufacturing apparatus for various thin films used in a semiconductor manufacturing process, a thermal reaction furnace such as an impurity diffusion furnace or an oxidation furnace for forming an oxide film is used. In the heating device (heating element structure) for heating, the shape of the piece (element wire support) that supports the heating element element wire such as nichrome or canthal is set to the piece surface (width d x height) facing the object to be heated. L) is tapered so that the area covered by the inner wall of the through hole of the heating element wire is as small as possible within the range allowed by the mechanical strength of the heating element wire. The amount of heat radiation radiated to the object to be heated is reduced and the mass of the piece is made as light as possible to minimize the amount of heat storage. As a specific shape of the piece supporting the heating element wire in the heating device of the thermal reaction furnace of the present invention,
For example, as shown in FIG. 1 and FIG. 2, the strand support body (piece) 4 has a trapezoidal shape that is tapered in the direction of the object to be heated, and the strand of the piece 4 supporting the heating element strand 3 is formed. By reducing the area of the heating element shielded by the inner wall of the through hole as much as possible, the heat radiation area from the heating element element wire 3 to the object to be heated is expanded as much as possible, and the piece 4
The mass of itself is reduced to improve the heating efficiency. That is, like the trapezoidal cross-sectional shape of the piece 4 shown in FIG. 2, a trapezoidal shape in which the area is reduced from a to a ′ with respect to the direction of the object to be heated corresponds to a−a ′ = b + c. The heat radiation area of the heating element element wire 3 can be increased by an amount corresponding to that of the prior art, and the heat radiation amount to the object to be heated can be improved accordingly. For example, 6 in a spiral
In the case of a heating device that supports the heating element wires 3 through 20 pieces 4 in one turn of the heating element wires 3 wound with 0 turns, assuming that a = 1 of the piece 4, a ′ = b = c = 1/3
When the piece 4 of the present invention shown in FIG.
Compared to the conventional piece 5 (see FIG. 6), the heat capacity is about 2/3, and conventionally, the heat capacity required to heat 20 × 60 = 1200 pieces is 1200 × 2/3 = 800 pieces. Any heat capacity can be used as long as it can be heated, and the heat capacity for heating 400 subtractions can be reduced. Furthermore, since the exposed area of the electric heating element wire 3 on the side of the object to be heated of the piece 4 is larger than that when the conventional piece 5 (see FIG. 6) is used,
The amount of heat radiation is increased correspondingly, and the heating efficiency is improved.

Further, the shape of the piece 4 for penetrating and supporting the heating element wire 3 of the present invention may be a triangular shape or an inverted T-shaped cross-sectional shape as shown in FIG. 3 or FIG. The effect of improving heating efficiency is the same as that of the trapezoidal piece 4 shown in FIG. However, the heat resistance and mechanical strength of the piece 4 should be taken into consideration when designing in consideration of the support of the heating element element wire 3 at a high temperature. The piece structure supporting the heating element wire used in the heating device of the thermal reaction furnace of the present invention has a narrower side facing the object to be heated to increase the exposed area of the heating element wire and increase the heat radiation amount. Since the mass of the piece can be made smaller than that of a conventional rectangular parallelepiped piece, the heat storage amount of the piece can be reduced. Particularly in a heater for high temperature heating, the number of windings of the heating element wire or the row of pieces of the heating element wire can be reduced. The greater the amount, the better the effect that the heat radiation amount and the heating efficiency can be improved.

[0007]

Embodiments of the present invention will be described below in more detail with reference to the drawings. Although the heating device mainly used in the vertical reaction furnace is described here as an example, it is needless to say that the present invention can be applied to a heating device such as a horizontal reaction furnace. FIG. 1 is an enlarged perspective view showing the configuration of a support portion of a heating element wire in a heating device of the present invention, and FIG. 2 is a view taken in the direction of arrow A in FIG. In the figure, the piece 4 has a substantially trapezoidal shape in which the width is tapered from a to a'in the direction facing the object to be heated.
The depth d, which is the distance in the direction of the object to be heated, and the height L, which is the distance in the vertical direction, depend on the material such as the heating element wire 3 and the specifications such as the wire diameter, or the specifications such as the temperature of the heating device and the heating time. It is set arbitrarily. Therefore, as compared with the conventional piece 5 (see FIG. 6) having the conventional width a, depth d, and height L, the piece 4 used in the heating device of the thermal reaction furnace of the present embodiment is almost a-. As much as a '= b + c,
The heat radiation area of the heating element wire 3 can be substantially increased, and the mass of the piece 4 of this embodiment is smaller than that of the conventional piece 5 by an amount corresponding to a−a ′ = b + c. Therefore, the heat storage amount of the piece 4 can be reduced by that amount, so that the heating efficiency can be significantly improved. In particular, in a heating device for a thermal reaction furnace that heats to a high temperature of 1000 ° C. or higher, the number of windings of the heating element wire increases, and the number of piece rows also increases because the heating element wire is prevented from sagging. The heating efficiency can be further improved by using the piece structure of the embodiment.
Although the trapezoidal piece shown in FIGS. 1 and 2 has been described in the embodiment of the present invention, the substantially triangular piece 4 shown in FIG. 3 may be used, and the inverted T-shaped piece shown in FIG. Even the piece 4 has substantially the same effect as the trapezoidal piece 4. However, in this case, it is needless to say that the piece needs to have a shape and structure capable of sufficiently withstanding mechanical strength and heat resistance depending on the heating temperature or the specifications of the heating furnace. In the above embodiments, the piece having the structure in which the heating element wire is supported by being passed through the hole provided in the piece has been described as an example, but it is not always necessary to pass the heating element wire through the hole, and the U-shaped member is formed on the upper surface of the piece. Even if the groove is provided and the heating element element wire is fitted in the groove, the same effect as that of the above-described embodiment can be obtained by forming the taper shape in the direction of the object to be heated.

[0008]

As described in detail above, in the heating apparatus of the thermal reactor using the strand support (piece) for supporting the heating element strand of the present invention, the heating element strand is formed by the strand supporting body. Since the area to be shielded can be minimized to increase the amount of heat radiation in the direction of the object to be heated, and the mass of the strand support can be reduced to reduce the amount of heat storage, various reactors can be used. The heating efficiency can be significantly improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of an element wire support (piece) and a heating element element wire exemplified in an embodiment of the present invention.

FIG. 2 is a schematic view showing a trapezoidal piece structure as seen from the direction of arrow A in FIG.

FIG. 3 is a schematic diagram showing a triangular piece structure exemplified in an example of the present invention.

FIG. 4 is a schematic view showing an inverted T-shaped piece structure exemplified in the embodiment of the present invention.

FIG. 5 is a schematic diagram showing an example of the configuration of a conventional heating device for a thermal reaction furnace.

FIG. 6 is an enlarged view of a portion B of FIG. 5, showing a perspective view showing a configuration of a conventional strand support and a heating element strand.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Heater case 2 ... Heat insulation layer 3 ... Heating element (heater) element wire 4, 5 ... Element wire support body (piece) 6 ... Element wire through hole

Claims (2)

[Claims] 1. A heating element for a heating reactor and a heating device for a thermal reaction furnace for supporting the heating element through the holes of a plurality of element supporting members and fixing the heating element to the furnace wall of the heating furnace. The shape of the support is tapered with respect to the direction of the object to be heated, and the area where the heating element wires are shielded by the inner wall surface of the hole of the wire support is reduced to increase the heat radiation area in the direction of the object to be heated. In addition, the heating device for a thermal reaction furnace is characterized in that a strand support having a structure that reduces the mass of the strand support to reduce the amount of heat storage is provided. 2. The heating element wire according to claim 1, wherein the heating element wire is a heating device used in a thermal reaction furnace spirally wound in multiple stages in a direction parallel to an object to be heated, Trapezoid taper, triangle shape or inverted T with respect to the direction of the heated object
A heating device for a thermal reaction furnace, which has a shape.