JP2000077344A - Tubular member for semiconductor heat treatment oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To adapt to a rapid temperature change by providing a plurality of fins on the surface of a pipe body in the axial direction of the pipe body. SOLUTION: A tubular member for a semiconductor heat treatment oven, for example a reactor core tube 1, is made of Si-impregnated SiC sintered body, and the reactor core tube 1 is provided with a tube body 2 in a closed-end cylindrical shape, an outer fin 3 that is provided on the surface, for example an outer surface 2o, of the tube body 2, and an inner fin 4 that is provided on an inner surface 2i. Each plurality of outer fins 3 and inner fins 4 are in axial direction (longer direction) of the pipe body 2 and are provided on the outer surface 2o and the inner surface 2i so that they reach a bottom surface part 6 from an opening 5, and the length of the outer fin 3 and the inner fin 4 is 20% or longer than the length of the pipe body 2. The radius of the pipe body 2 in a cylindrical shape is, for example, 193 mm, the coating thickness of the pipe body ranges from 2 to 7 mm, and the total of the coating thickness of the pipe body 2 and the sum of the height of the outer fin and that of the inner fin 4 ranges from 7 to 14 mm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tubular member for a semiconductor heat treatment furnace, and more particularly to a tubular member for a semiconductor heat treatment furnace adaptable to a rapid temperature change.

[0002]

2. Description of the Related Art In general, semiconductor heat treatment involves holding a semiconductor wafer in a tubular member for an isothermal semiconductor heat treatment furnace, for example, a furnace core tube, and performing heat treatment of the semiconductor wafer by utilizing a thermal change during the isothermal holding.

Conventionally, a furnace core tube 21 having a cylindrical body with a bottom and a flat surface as shown in FIGS. 8 and 9 has been used for heat treatment of a semiconductor wafer. Since the tube 21 is simply a furnace body 20 having a flat surface, it is hardly adapted to the use conditions during the isothermal holding of the heat treatment, and an improvement has been made such that the tube 21 is easily adapted to the use conditions during the isothermal hold.

As an improvement measure, for example, Japanese Utility Model Application Laid-Open No. 2-8
As described in JP-A No. 9826, the thickness of the member is devised to prevent thermal deformation during use at high temperatures, a member provided with a reinforcing member on the surface of the main body, or as described in JP-A-2-16723. A tubular member having a heat-capacity increasing portion on the low-temperature portion side so as to allow a long soaking portion during high-temperature use; And a fin for controlling the gas flow in the tubular member so that the heat treatment can be performed.

[0005] All of the remedies disclosed above are for adapting the furnace core tube to the use conditions during the isothermal holding at a high temperature.

On the other hand, in recent years, in order to improve the characteristics of semiconductor products, a method of increasing the temperature rise and fall during heat treatment has been developed and put to practical use. In addition, with the increase in the diameter of semiconductor wafers, single wafer processing has been adopted, and rapid heating and rapid cooling have been studied in order to shorten the heat treatment time and improve the production efficiency. In order to adapt to the rapid rise and fall of temperature accompanied by such a rapid temperature change, it is necessary to reduce the heat capacity of the members and to improve the heat transfer characteristics. Therefore, any conventional furnace core tube that adapts the furnace core tube to use conditions during isothermal holding at a high temperature is insufficient.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above circumstances, and has as its object to provide a tubular member for a semiconductor heat treatment furnace which can be particularly adapted to a rapid temperature change.

[0008]

Means for Solving the Problems In order to achieve the above object, the invention of claim 1 of the present application comprises a pipe main body and a plurality of fins provided on the surface of the pipe main body along the axial direction of the pipe main body. The gist of the present invention is to provide a tubular member for a semiconductor heat treatment furnace.

According to a second aspect of the present invention, there is provided a tubular member for a semiconductor heat treatment furnace according to the first aspect, wherein the surface of the tube body is an outer surface and an inner surface of the tube body.

In the third aspect of the present invention, the sum of the height of the outer fin provided on the outer surface and the height of the inner fin provided on the inner surface is not more than 3.5 times the wall thickness of the tube body. The gist is a tubular member for a semiconductor heat treatment furnace according to claim 1 or 2.

In the invention of claim 4 of the present application, the wall thickness of the tube main body is 2 to 7 mm, and the sum of the wall thickness of the tube main body and the sum of the heights of the fins is 7 to 14 mm. 4. The method according to claim 1, wherein the width is 7 mm or less.
The gist is a tubular member for a semiconductor heat treatment furnace according to any one of the above.

5. The semiconductor heat treatment furnace according to claim 1, wherein the number of the fins is 6 to 10 per 100 mm in the circumferential direction of the tube body. It is intended to be a tubular member for use.

The semiconductor heat treatment according to any one of claims 1 to 5, wherein the length of the fin is at least 20% of the axial length of the tube main body. The gist is a tubular member for a furnace.

According to a seventh aspect of the present invention, the shape of the cross section perpendicular to the axial direction of the fin is any one of a rectangle, a trapezoid, a semicircle, and a semiellipse. The gist is a tubular member for a semiconductor heat treatment furnace according to the above item 1.

According to the invention of claim 8 of the present application, the fin has a cross section perpendicular to the axial direction in which a flat portion or a curved surface of 0.5 to 2.5 mm is chamfered at the corner portion and the rising portion from the surface of the tube main body. 8. The method according to claim 1, wherein:
The gist is a tubular member for a semiconductor heat treatment furnace according to any one of the above.

The tubular member for a semiconductor heat treatment furnace according to any one of claims 1 to 8, wherein the tubular member for a semiconductor heat treatment furnace is made of a Si-impregnated SiC sintered body. The gist is to be a member.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a tubular member for a semiconductor heat treatment furnace according to the present invention will be described below with reference to the accompanying drawings.

The tubular member for a semiconductor heat treatment furnace according to the present invention, for example, the furnace core tube 1 is made of a Si-impregnated SiC sintered body,
As shown in FIGS. 1 and 2, the furnace core tube 1 has a cylindrical tube body 2 with a bottom and a surface of the tube body 2, for example, an outer surface 2.
o, and an inner fin 4 provided on the inner surface 2i.

A plurality of the outer fins 3 and the inner fins 4 are provided on the outer surface 2o and the inner surface 2i, respectively, along the axial direction (longitudinal direction) of the tube body 2 from the opening 5 to the bottom surface 6. The length of the outer fins 3 and the inner fins 4 is at least 20% of the length L of the tube body 2.

As shown in FIG. 3, the radius R of the cylindrical tube body 2 is, for example, 193 mm, the wall thickness t0 of the tube body 2 is 2 to 7 mm, for example, 3 mm, and the wall thickness of the tube body 2 is t0 and the height t1 of the outer fin 3 (for example, 3.5 m
m) and the sum of the height t2 (for example, 3.5 mm) of the inner fins 4 is 7 to 14 mm, for example, 10 mm.

The width W of the outer fin 3 and the inner fin 4
1 is 7 mm or less, for example, 5 mm, and the distance W2 between adjacent outer fins 3 is, for example, 7.7 mm. Further, the sum of the number of the outer fins 3 and the number of the inner fins 4 is 6 to 10 pieces, for example, 8 mm per 100 mm in the circumferential direction of the tube body 2.
Individual.

As shown in FIG. 4, the cross section of the outer fin 3 and the inner fin 4 perpendicular to the axial direction of the tube body 2 is rectangular, and the corner c1 and the rise c2 from the surface of the tube body are 0. A flat or curved chamfer of 0.5 to 2.5 mm is formed. The cross-sectional shapes of the outer fins 3 and the inner fins 4 may be trapezoidal, semicircular, or semielliptical in addition to the above-described rectangle.

In order that the article to be heat-treated, for example, a semiconductor wafer W, loaded in the furnace core tube 1 is uniformly heated and cooled over the entire length of the furnace core tube 1, the outer fin 3 and / or the inner fin are required. 4 must be longer than the length of the semiconductor wafer W. Therefore, the length of the outer fins 3 and / or the inner fins 4 is preferably 20% or more of the length in the central axis direction of the tube main body 2, and if less than 20%, the semiconductor wafer W is uniformly heated. Can not.

When the sum of the number of the outer fins 3 or the inner fins 4 is less than 6, and / or the sum T of the wall thickness t0 of the tube body 2 and the heights t1 and t2 of the fins 3 and 4 is larger. , 7 mm, both fins 3,
4, the total cross-sectional area of the fin cross section becomes smaller, and the heat transfer efficiency becomes worse.

When the sum of the numbers of the outer fins 3 and the inner fins 4 is larger than 10, and / or
If the sum of the heights of 4 exceeds 3.5 times the wall thickness of the pipe body,
And / or when the total T of the wall thickness t0 of the tube body 2 and the heights t1 and t2 of the two fins 3 and 4 is larger than 14 mm and / or the width of both the fins 3 and 4 exceeds 7 mm, The ratio of the fins 3 and 4 to the sum of the cross-sectional areas of the tube body 2 and the fins 3 and 4 increases,
If the sum of the cross-sectional areas is not increased, the wall thickness of the tube main body 2 becomes small, and the tube main body 2 may be damaged.

When the width of both fins 3 and 4 is smaller than 3 mm, for example, or when the total T of the wall thickness t0 of the tube body 2 and the heights t1 and t2 of both fins 3 and 4 is 14 mm, for example.
If it is larger than this, the stress applied to the tips of both fins 3 and 4 will be greater than in the case of a flat tubular member without fins, and there is a possibility that the tube body 2 may be damaged.

When the cross-section of the fins 3 and 4 is rectangular, trapezoidal, semicircular, or semi-elliptical, the strength is excellent and the heat transfer efficiency is good.

The flat or curved chamfer at the corners of the fins 3 and 4 and the rising portion from the surface of the pipe body is 0.5 mm.
If it is smaller, there is no chamfering effect, and if it is larger than 2.5 mm, the widths of the tips of both fins 3 and 4 become narrower, and the strength is reduced.

Since the furnace core tube 1 according to the present invention has the above-described structure, for example, to form an oxide film on the surface of a semiconductor wafer W, the semiconductor wafer W is placed on a wafer boat B, The boat B is loaded into the furnace core tube 1. Thereafter, the furnace heating means (not shown) is energized to heat the furnace core tube 1 and, if necessary, a gas is introduced into the furnace core tube 1 to form an oxide film on the surface of the semiconductor wafer W. . After the oxide film is formed, the furnace heating means is deenergized, the furnace core tube 1 is cooled, and the wafer boat Bo on which the semiconductor wafer W is placed is taken out.

In this oxide film forming step, the thickness t0 of the tube body 2 is, for example, 3 mm, and the thickness t0 of the tube body 2, the height t1 of the outer fins 3, and the height t1 of the inner fins 4.
If the sum T of the sum of 2 is 10 mm, for example, the cross-sectional area of the furnace core tube 1 is reduced and its weight is also reduced, so that the heat capacity of the furnace core tube 1 is reduced and the thermal responsiveness of the furnace core tube 1 is reduced. (Followability) is good. That is, in a limited (constant) cross-sectional area of the furnace core tube 1, a proper balance between the wall thickness t0 of the tube main body 2 and the heights t1 and t2 of the fins is taken to improve the thermal responsiveness of the furnace core tube 1. Well done.

Therefore, rapid heating and rapid cooling are performed in accordance with the energizing and deenergizing of the furnace heating means, and the workability of the oxide film forming step is improved.

The sum of the number of the outer fins 3 or the number of the inner fins 4 is eight, and the sum of the heights of the two fins 3, 4 is a fin whose height is 2.3 times the wall thickness of the tube body. The total T of the wall thickness t0 of the tube body 2 and the heights t1 and t2 of the fins 3 and 4 is, for example, 10 mm.
Is, for example, 5 mm, so that if the ratio of the tightening of the two fins 3 and 4 to the sum of the cross-sectional areas of the tube body 2 and the two fins 3 and 4 is appropriate, the strength of the tube body 2 does not decrease, There is no fear that the furnace core tube 1 will be damaged.

Next, another embodiment will be described.

The tubular member for a semiconductor heat treatment furnace shown in FIG. 5 is a single-wafer type furnace core tube 10 which is made of Si-impregnated S
A flat dome-shaped tube body 11 made of an iC sintered body, an outer fin 12 provided on an outer surface 11o along an axial direction of the tube body 11, and an inner fin 13 provided on an inner surface 11i.
have.

For example, in order to form an oxide film on the surface of a semiconductor wafer W using the furnace core tube 10 of the present embodiment, one semiconductor wafer W is placed on a single wafer type susceptor S, and this susceptor S Is loaded into the furnace core tube 10. Thereafter, the furnace heating means (not shown) is energized to heat the furnace core tube 10 and, if necessary, a gas is introduced into the furnace core tube 10 to form an oxide film on the surface of the semiconductor wafer W. . After the oxide film is formed, the furnace heating means is deenergized to cool the furnace core tube 10 and the semiconductor wafer W is cooled.
The susceptor s on which is mounted is taken out.

In this oxide film forming step, the pipe body 1
1 is, for example, 3 mm, and
The total T of the thickness of the outer fin 12 and the sum of the heights of the inner fins 13 is set to, for example, 10 mm, and the cross-sectional area of the furnace core tube 10 is reduced and its weight is also reduced. The heat capacity is kept small, and the thermal response of the furnace core tube 10 is good. That is, it is rapidly heated and rapidly cooled in accordance with the energization and de-energization of the furnace heating means, thereby improving the workability of the oxide film forming step.

The sum of the number of the outer fins 12 or the inner fins 13 is eight, and the sum of the heights of the two fins 3 and 4 is 2.3 times the wall thickness of the pipe body 11 and is a low fin. The sum of the wall thickness of the tube body 11 and the heights of the fins 12 and 13 is, for example, 10 mm, and the width of the fins 12, 13 is, for example, 5 mm.
The ratio of the fins 12 and 13 to the sum of the cross-sectional areas of the fins 13 and 13 was made appropriate, the strength of the tube body 11 was not reduced, and the furnace core tube 10 was also prevented from being damaged.

In the above-described two embodiments, the tubular member for a semiconductor heat treatment furnace is made of a Si-impregnated SiC sintered body, but may be made of a high-purity heat-resistant refractory such as quartz glass.

Further, as shown in the embodiment, the fins need not necessarily have the same thickness between the outer fin and the inner fin, and need not be arranged at equal intervals.

In the case of heating the tubular member for a semiconductor heat treatment furnace from the outside, rapid heating and quenching on the outer surface side of the tubular member for a semiconductor heat treatment furnace is important. Within the thickness range, the fin thickness may be such that the outer fins are thicker and the inner fins are thinner for efficient heat transfer. It is also possible that the thickness of the inner fin is 0, that is, only the outer fin is provided.

Conversely, when a gas having good heat conductivity such as He or H ₂ is present in the tubular member for a semiconductor heat treatment furnace,
In some cases, it is better to make the thickness of the inner fin relatively large in consideration of the efficiency of heat transfer in the tubular member for a semiconductor heat treatment furnace.

The upper and lower portions of the tubular member in the case of the horizontal tubular member for a semiconductor heat treatment furnace as shown in the embodiment,
Alternatively, when a vertical temperature difference occurs between the top and bottom of the tubular member in the case of using a tubular member for a semiconductor heat treatment furnace, and a difference occurs in the effect of convection, the circumferential spacing of the fins may be made uneven. Good.

The number of the outer fins and the number of the inner fins do not need to match, and the outer fins and the inner fins do not have to face each other.

[0044]

EXAMPLES Bending strength and thermal responsiveness test (1) Object of the test: The bending strength and the thermal responsiveness of the example and the conventional example are measured and compared.

(2) Preparation of Sample a. Example: A straight body tube with one side sealed spherically is made of Si-impregnated Si
It was made of a C sintered body. The dimensions of each part are as shown in Table 1.

[0046]

[Table 1] b. Conventional example: One side of a flat straight tube without fins was sealed in a spherical shape.

Table 2 shows the dimensions of each part.

[0048]

[Table 2] (3) Measurement method: a. Strength test: As shown in FIG. 6, the sample was supported by the cantilever at the open end side of the sample, and a weight Wt (3 kg) corresponding to the weight of the semiconductor wafer and the wafer boat was placed at a position near the sealed end inside the sample.
f) is placed, and the deflection δ of the tubular member at the sealing end position is measured.

B. Thermal response test: 400 as shown in FIG.
The tubular member is pulled out of the furnace maintained at a temperature of 30 ° C. at 30 cm / min, and the cooling rate near the inner surface near the sealed end is measured with a thermocouple.

(4) Measurement results: a. Strength test result: As shown in Table 3, there is no difference in strength between the two.

[0051]

[Table 3] b. Thermal response test result: As shown in Table 4, the maximum cooling rate of the example was 124 ° C./min, and 98 ° C./min of the conventional example.
min by about 26%, indicating that the example was excellent in thermal response.

[0052]

[Table 4]

[0053]

According to the tubular member for a semiconductor heat treatment furnace according to the present invention, by forming a low fin in the axial direction of the tubular member, an appropriate balance between the wall thickness of the tube main body and the height of the fin can be obtained. The thermal responsiveness of the tubular member can be improved without reducing the strength of the tubular member.

Further, since the fins are provided on the outer surface and the inner surface of the surface of the tube main body, the thermal responsiveness of the tubular member can be further improved without lowering the strength of the tubular member. The sum of the height of the outer fin provided on the outer surface and the height of the inner fin provided on the inner surface is 3.5 of the wall thickness of the pipe body.
Since the thickness is not more than twice, it is not necessary to reduce the wall thickness more than necessary, and the thermal responsiveness of the tubular member can be improved while maintaining the strength of the tubular member.

Further, the thickness of the tube body is 2 to 7 mm, the sum of the thickness of the tube body and the sum of the heights of the fins is 7 to 14 mm, and the width of the fin is 7 mm or less. Therefore, the ratio of the wall thickness of the tube body to the cross-sectional area of the fin becomes appropriate, and the thermal responsiveness of the tubular member can be improved while maintaining the strength of the tubular member.

The number of fins is 100 mm in the circumferential direction of the pipe body.
By setting the number of hits to 6 to 10, the thermal response of the tubular member can be improved while maintaining the strength of the tubular member.

The length of the fin is 2 times the axial length of the tube body.
0% or more, while maintaining the strength of the tubular member,
Along with improving the thermal responsiveness of the tubular member,
The temperature in the tubular member can be made uniform.

By making the shape of the cross section perpendicular to the axial direction of the fin any of a rectangle, a trapezoid, a semicircle, and a semiellipse, the strength and heat transfer characteristics can be improved.

The cross-sectional shape of the fin perpendicular to the axial direction is 0.5 to 2.5 at the corner portion and the rising portion from the surface of the pipe main body.
Since the flat or curved chamfer of mm is formed, the strength of the fin can be maintained.

When the tubular member is manufactured from a Si-impregnated SiC sintered body, the effect of maintaining the strength and improving the thermal response of the tubular member are most remarkable.

[Brief description of the drawings]

FIG. 1 is a sectional view of a tubular member for a semiconductor heat treatment furnace according to the present invention, taken along the line AA of FIG. 2;

FIG. 2 is a cross-sectional view of the tubular member for a semiconductor heat treatment furnace according to the present invention, taken along line 1B-B of FIG.

FIG. 3 is an explanatory diagram showing an enlarged portion X in FIG. 2;

FIG. 4 is an enlarged sectional view showing the fin of FIG. 3;

FIG. 5 is a sectional view of another embodiment of the tubular member for a semiconductor heat treatment furnace according to the present invention.

FIG. 6 is an explanatory view showing a strength test method.

FIG. 7 is an explanatory view showing a thermal responsiveness test method.

FIG. 9D-D of a conventional tubular member for a semiconductor heat treatment furnace.
Sectional view along the line.

FIG. 9 is a sectional view of a conventional tubular member for a semiconductor heat treatment furnace.
Sectional view along the line.

[Description of Signs] 1 tubular member for semiconductor heat treatment furnace (furnace core tube) 2 tube main body 2o outer surface 2i inner surface 3 outer fin 4 inner fin 5 opening 6 bottom part 10 furnace core tube 11 tube main body 11o outer surface 11i inside Surface 12 Outer fin 13 Inner fin Bo Wafer boat S Single wafer susceptor W Semiconductor wafer

Claims (9)

[Claims] 1. A tubular member for a semiconductor heat treatment furnace, comprising: a tube main body; and a plurality of fins provided on a surface of the tube main body along an axial direction of the tube main body. 2. The tubular member for a semiconductor heat treatment furnace according to claim 1, wherein the surface of the tube main body is an outer surface and an inner surface of the tube main body. 3. The sum of the height of the outer fins provided on the outer surface and the height of the inner fins provided on the inner surface is not more than 3.5 times the wall thickness of the tube body. Claim 1
Or the tubular member for a semiconductor heat treatment furnace according to 2. 4. The pipe body has a wall thickness of 2 to 7 mm,
The sum of the wall thickness of the pipe main body and the sum of the heights of the fins is 7 to 14 mm, and the width of the fins is 7 mm or less. Tubular member for a semiconductor heat treatment furnace. 5. The number of the fins is 10 in the circumferential direction of the pipe body.
The tubular member for a semiconductor heat treatment furnace according to any one of claims 1 to 4, wherein the number is 6 to 10 per 0 mm. 6. The tubular member for a semiconductor heat treatment furnace according to claim 1, wherein the length of the fin is at least 20% of the axial length of the tube body. 7. The fin according to claim 1, wherein a shape of a cross section perpendicular to the axial direction of the fin is one of a rectangle, a trapezoid, a semicircle, and a semiellipse. Tubular member for a semiconductor heat treatment furnace. 8. The cross-sectional shape of the fin perpendicular to the axial direction is 0.5 to 0.5 mm at the corner and at the rising portion from the surface of the pipe main body.
The tubular member for a semiconductor heat treatment furnace according to any one of claims 1 to 7, wherein a 2.5 mm flat or curved chamfer is formed. 9. The tubular member for a semiconductor heat treatment furnace according to claim 1, wherein the tubular member for a semiconductor heat treatment furnace is made of a Si-impregnated SiC sintered body.