JP3393031B2 - Reactor for moisture generation - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to improvement of a water-generating reactor used in a semiconductor manufacturing facility.

[0002]

2. Description of the Related Art For example, when a silicon oxide film is formed by a water oxidation method in semiconductor manufacturing, at least 1000 c
Ultra high purity water exceeding c / min is required. Therefore, the applicant of the present invention has previously developed a reactor for moisture generation having a structure shown in FIG. 4 and has disclosed it as Japanese Patent Application No. 8-242246.

The reaction furnace main body 21 shown in FIG. 4 has heat resistant furnace main body members 22 and 23 having a gas supply joint 24 and a moisture gas extraction joint 25, and both furnace main body members 22 inside the reaction furnace 21. , 23 of the gas supply passage 24a and the moisture gas outlet passage 25a, the inlet side reflection plate 29a and the outlet side reflection plate 29b, the filter 30 provided at the center of the inside of the reaction furnace 21, and the furnace body member 23. It is formed from the platinum coating film 32 and the like provided on the inner wall surface. Further, the platinum coating film 32 is a barrier film 3 made of a nitride such as TiN formed on the inner wall surface of the furnace body member 23.
It is formed by fixing a platinum film 32b on 2a by a vapor deposition method or an ion plating method.

The hydrogen and oxygen supplied to the inside of the reaction furnace main body 21 through the gas supply passage 24a are diffused by the diffusing member composed of the inlet side reflecting plate 29a, the filter 30 and the outlet side reflecting plate 29b. Contact with the platinum coating film 32. Oxygen and hydrogen that have come into contact with the platinum coating film 32 have increased reactivity due to the catalytic action of platinum, and are in a so-called radicalized state. The radicalized hydrogen and oxygen react instantly at a temperature lower than the ignition temperature of the hydrogen mixed gas, and produce water without high temperature combustion.

The reactor main body 21 shown in FIG. 4 is capable of significantly reducing the size of the water generating device, and has a high reactivity and a high responsiveness to produce high-purity water or high-purity water in an amount exceeding 1000 cc / min. Since it is possible to obtain a mixed gas with oxygen, it has received epoch-making attention in the field of semiconductor manufacturing technology.

FIG. 5 shows the reaction furnace body of FIG.
34 mmφ, thickness 70 mm, internal volume about 490 cc, water generation rate 1000 cc / min, furnace temperature about 400 ° C.) 21
It shows the change with time of the moisture generation reaction rate in
Even if the source gas is an oxygen-rich or hydrogen-rich gas, it is possible to stably generate water with a water generation reaction rate of about 98.5 to 99.0%.

However, the temperature of the reactor body 21 is about 400
It is difficult to raise the water generation reaction rate to about 99.0% or more under the condition that the water generation rate is 1000 ° C. or less and the water generation rate is 1000 cc / min or more. Hydrogen will be mixed in the generated water. As a result, there is a problem in that it is impossible to take out only pure water containing no hydrogen or oxygen or a mixture of pure water containing no hydrogen and oxygen.

[0008]

An object of the present invention is to further increase the reaction rate of hydrogen and oxygen in the reaction furnace main body 21 shown in FIG. 400 ° C or less, water generation amount 1000 cc / min
Under the above conditions, the present invention provides a reactor for water generation capable of stably obtaining a water generation reaction rate of 99% or more for a long period of time.

[0009]

By the way, in the reactor main body 21 of FIG. 4, the cause of the unreacted hydrogen and oxygen being mixed into the moisture gas outlet passage 25a is that the platinum coating film 32 is brought into contact with the moisture coating gas. Directly, without moisture gas outlet passage 2
When oxygen or hydrogen reaches 5a, and when the one carrier is radicalized but reaches the moisture gas outlet passage 25a without reacting with hydrogen or oxygen and returns to the state before being radicalized here. There are two possible cases, but it is assumed that the former case is overwhelmingly prevalent.

According to the results of experiments conducted by the inventors of the present application, when the outlet-side reflection plate 29b is removed from the reaction furnace main body 21 shown in FIG. 4, the temperature of the reaction furnace is 400 ° C. and water is generated as shown in FIG. When the amount is 500 cc / min and the gas excess is 0, the water generation reaction rate is about 91%. This reaction rate is not the data under exactly the same conditions because the amount of water generated is different, but the reaction rate of water generation in the case of FIG.
%), Which is about 7% lower.

This means that in the absence of the outlet side reflection plate 29b, a considerable amount of oxygen and hydrogen reach the moisture gas outlet passage 25a directly without being converted into radicals. It is shown that the water generation reaction rate can be improved by improving 29b.

Further, as is clear from FIG. 6, when the outlet side reflection plate 29b is not provided, the moisture generation reaction rate decreases as the source gas becomes richer in hydrogen. For example, when the reactor temperature is 400 ° C. and the hydrogen generation rate is 500% / min and the hydrogen generation is 100% rich, the water generation reaction rate is about 86%, while the oxygen generation rate is 100% rich. In this case, it is about 97%, and there is a difference of about 11% between the two.

That is, the reactor main body 21 having the structure shown in FIG.
In the inside of oxygen, oxygen is relatively diffused and its linear running property is small, while hydrogen is relatively difficult to diffuse and its linear running property is high. In the case of 2, it is assumed that oxygen accompanies the linear flow of hydrogen and the oxygen that reaches the moisture gas outlet passage 25a increases without being radicalized.

Therefore, the inventor of the present invention has the reaction furnace main body 2 of FIG.
In 1, in the case of not only oxygen-rich source gas but also hydrogen-rich source gas, by enhancing the gas diffusivity of the outlet side reflection plate 29b, particularly the diffusivity with respect to hydrogen,
It was conceived that the water generation reaction rate can be made higher than the reaction rate of about 98 to 99% in the case of FIG. In addition, based on this idea, we produced exit side reflectors and diffusers of various structures, and conducted many moisture generation tests using them.

The present invention was created based on the above idea and the results of the moisture generation test based on the idea. The invention according to claim 1 is a combination of the furnace body member 2 and the furnace body member 3. A reactor main body 1 having a space 1a formed therein; a gas supply passage 2c formed in the furnace body member 2 for introducing a raw material gas into the space 1a;
A moisture gas outlet passage 3c for deriving the generated water from the space portion 1a; a moisture gas outlet passage 3c fixed to the space portion side of the furnace body member 2 coaxially with the moisture gas outlet passage 2c;
an entrance side reflection plate 9 comprising a cylindrical case body 9a having c and a reflection plate 9b closing the inner end surface of the case body 9a;
Filter 1 disposed in the space 1a of the reactor body 1
0; a cylindrical case body 12a fixed to the space side of the furnace body member 3 coaxially with the moisture gas outlet passage 3c and having a through hole 12e in the wall surface, and a reflection plate for closing the inner end surface of the case body 12a. 12b and an outlet-side reflector / diffuser 1 including a diffusion filter 12c provided inside the case body 12a and a platinum coating film 12d provided on the diffusion filter 12c.
2; and the platinum coating film 13 provided on the inner wall surface of the reactor body 1 is a constituent of the invention.

According to a second aspect of the present invention, the filter 10 according to the first aspect of the invention is a filter 10 having a through hole of 200 μm or less.

According to a third aspect of the present invention, the diffusion filter 12c according to the first aspect of the invention is a diffusion filter 12c having a through hole of 50 μm or more.

According to a fourth aspect of the present invention, the reaction furnace main body 1 according to the first aspect of the present invention includes a furnace body member 2 having a curved surface-shaped concave portion 2a having substantially the same shape, and a curved surface-shaped concave portion. 3a and the furnace main body member 3 are combined and formed in a facing manner,
The filter 10 is arranged in the central portion of both body members 2 and 3.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view of a reactor body for moisture generation according to the present invention. In addition, Figure 2 shows the exit side reflection
FIG. 3 is an enlarged cross-sectional view of the diffuser, and FIG. 3 is a cross-sectional view taken along line II of FIG. In FIG. 1, 1 is a reaction furnace body, 2 and 3 are furnace body members, 4 is a gas supply joint, 5 is a moisture gas extraction joint, and 6
Is a filter flange, 7 is a reactor mounting bolt, 8 is a gas diffusion member, 9 is an inlet side reflector, 10 is a filter,
11 is a filter receiving piece of the filter flange, 12 is an outlet side reflection / diffuser, and 13 is a platinum coating film,
The reaction furnace 1 is formed into a short cylindrical shape by welding two stainless steel furnace body members 2 and 3 formed in substantially the same shape in an airtight manner.

The one furnace body member 2 is provided with a concave portion 2a having a curved surface on the bottom surface inside thereof, and a gas supply passage 2c is bored in the central portion thereof. Further, the gas supply joint 4 is provided on the outer side surface, and the gas supply passage 4 a of the gas supply joint 4 provided on the outer side surface is provided with the recess portion 2.
It is connected to the inside of a. Similarly, the other furnace body member 3
Has a concave portion 3a having a curved surface on the bottom surface, and a gas supply passage 3c is formed in the central portion. Further, a joint 5 for taking out moisture gas is provided on the outer side surface, and a joint 5 for taking out moisture gas provided on the outer side surface is provided.
The moisture gas outlet passage 5a is communicated with the inside of the recess 3a.

Flange bodies 2b and 3b are formed on the inner side surfaces of the two furnace body members 2 and 3, respectively, and the two flange bodies 2b and 3b are welded and fixed in a hermetically sealed manner via a filter flange 6. A reactor main body 1 having a space 1a inside is constructed. In FIG. 1, both flange bodies 2b and 3b are fixed by welding, or both flange bodies 2b and 3b are detachably assembled and fixed by a clamp (not shown) via a gasket (not shown). It may be configured to. Further, in FIG. 1, both main body members 2 and 3 are formed to have substantially the same shape, but one of them has a shape of a bottomed cylindrical body, and the other has a flange shape for closing the opening of the cylindrical body. Of course, it may be formed into a shape.

The gas diffusion member 8 is composed of an inlet side reflection plate 9, a filter 10, an outlet side reflection / diffusion plate 12, etc., and is arranged inside the reaction furnace body 1 as shown in FIG. . That is, the entrance side reflection plate 9 is a case body 9a having a short tubular shape.
And a reflection plate 9b that closes the inner end surface of the case body 9a, and a through hole 9c is formed in the outer peripheral wall of the case body 9a.
Are formed. The inlet-side reflection plate 9 is arranged coaxially with the bottom surface of the furnace body member 2 at a position facing the gas supply passage 2c, and is welded and fixed thereto.

The filter 10 has a thickness of about 200 μm.
It is formed of a stainless steel filter having the following through holes, and in the present embodiment, a filter having a mesh-like through hole having an average of 2 μm is used. In addition, filter 1
A filter flange 6 made of stainless steel is welded to the outer peripheral edge of 0, and the filter 10 is welded and fixed to the furnace body members 2 and 3 via the filter flange 6.

Further, as shown in FIGS. 2 and 3, the outlet side reflecting / diffusing body 12 has a short cylindrical case body 12a,
A reflector 12b for closing the inner end surface of the case body 12a,
The diffusion filter 12c, a platinum coating film 12d provided on the outer surface of the diffusion filter 12c on the side of the space, a filter retainer 12f, etc.
A plurality of through holes 12e are formed in the outer peripheral wall of the inner portion of a. That is, the case body 12a, the reflection plate 12b, etc. are all made of stainless steel, and the reflection plate 12b
Is fixed to the case body 12a by spot welding. The diffusion filter 12c is formed of a stainless steel filter having a through hole of 50 μm or more.

On the outer surface of the diffusion filter 12c on the space side, a platinum coating film 1 having a thickness of 0.2 to 8 μm is formed.
2d is formed. That is, the platinum coating film 12d is formed of a TiN barrier film having a thickness of 0.1 to 5 μm formed on the outer surface of the diffusion filter 12c and a platinum film having a thickness of 0.1 to 3 μm formed thereon. In order to prevent the diffusion filter 12c from being clogged due to the formation of the platinum coating film 12d, the mesh-shaped through holes of the stainless steel filter forming the diffusion filter 12c have a size of 50 μm or more. In the embodiment, 70 μm and 200 μm) are selected.

Since the method of forming the platinum coating film 12d is the same as that of the platinum coating film 13 provided on the inner wall surface of the reaction furnace body 1 described later,
Detailed description is omitted here. Further, in the present embodiment, the platinum coating film 12d is applied to the diffusion filter 12c.
Although it is formed on the outer surface of the space portion side, it is possible to provide the platinum coating film 12d inside the diffusion filter 12c. Further, the outlet-side reflector / diffuser 12 is coaxially arranged on the bottom surface of the furnace body member 3 at a position facing the moisture gas outlet passage 5a, and is welded and fixed thereto.

In FIG. 1, the bottom surfaces of the furnace body members 2 and 3 are curved surfaces, but they may be flat bottom surfaces. In FIG. 1, the length of the entrance reflector 9 and the exit reflector / diffuser 12 is about 1/6 of the depth of the recess 2a and about 1 of the depth of the recess 3a. However, it is also possible to increase the length dimension so as to suppress the amount of gas passing through the central portion of the filter 10. Further, in FIG. 1, a disk type filter having a gas permeable portion on its entire surface is used as the filter 10. However, instead of this, the disk type and only the outer peripheral surface portion thereof are provided with a filter portion (gas You may make it use the filter of the structure made into the transmission part.

The platinum coating film 13 is made of SUS.
It is formed on the entire inner surface of the furnace body member 3 made of 316L. First, a barrier film 13a made of TiN is formed on the inner surface of the furnace body member 3, and then a platinum film 13b is formed thereon. The thickness of the barrier coating 13a is optimally about 0.1 μm to 5 μm. In FIG. 1, the TiN barrier coating 13a having a thickness of about 2 μm is formed by the ion plating method. Further, it is suitable that the platinum film 13b has a thickness of about 0.1 μm to 3 μm. In FIG. 1, the platinum film 13b having a thickness of about 1 μm is formed by the vacuum deposition method.

The barrier coating 13a may be formed by a PVD method such as an ion sputtering method or a vacuum deposition method, a chemical vapor deposition method (CVD method), a hot pressing method, a thermal spraying method, etc., in addition to the ion plating method. It is also possible to use. In addition to the vacuum vapor deposition method, an ion plating method, an ion sputtering method, a chemical vapor deposition method, a hot press method, or the like can be used as the method for forming the platinum coating 13b. Further, the barrier coating 13a is made of a conductive material such as TiN. A plating method can also be used when the substance has a property.

The gas injected into the case body 9a of the inlet side reflector 9 through the gas supply passage 4a of the gas supply joint 4 collides with the reflection plate 9b, and then the through hole 9c formed in the outer peripheral wall.
Is sprayed through and is diffused in the recess 2a so as to evenly pass through almost the entire surface of the filter 10 and the furnace body member 3
Into the recess 3a. In addition, the mixed gas of hydrogen and oxygen injected into the recess 3 a is the platinum coating film 13
Collide with each other evenly over the entire surface, so that the so-called catalyst is activated. Furthermore, the activated hydrogen and oxygen react instantly mainly in the recess 3a to generate water. Then, the moisture gas mainly formed in the recess 3a is led out to the moisture gas outlet passage 5a through the through hole 12e of the outlet-side reflector / diffuser 12 and the diffusion filter 12c.

By the way, the recess 3 is transmitted through the filter 10.
Most of the hydrogen and oxygen gas that entered into a was platinum film 1
3b is converted into radicals by collision and contact with 3b, and almost all of the radicalized hydrogen and oxygen react instantaneously and are converted into water. Further, although some of the hydrogen and oxygen gases that have entered the recess 3a may go straight on,
These straight hydrogen and oxygen gases collide with the reflection plate 12b and are re-diffused. As a result, hydrogen and oxygen that reach the diffusion filter 12c through the through holes 12e while not in contact with the platinum film 13b are greatly reduced.

On the other hand, in the present invention, the diffusion filter 12c provided with the platinum coating film 12d is provided in the exit side reflection / diffusion body 12. Therefore, hydrogen or oxygen gas that has reached the inside of the case body 12a through the through hole 12e without being in contact with the platinum film 13b hardly passes through the moisture gas outlet passage 3c as it is. It is converted into a radical by contact with 12d. That is, the hydrogen or oxygen gas under the non-radicalized state is radicalized by the platinum coating film 12d of the diffusion filter 12c, and the hydrogen or oxygen in the non-radicalized state becomes almost zero, and
The radicalized hydrogen and oxygen react instantaneously to generate water.

Further, since the diffusion filter 12c exists inside the case body 12, the moisture gas outlet passage 3 is left unreacted with hydrogen and oxygen in a radicalized state.
The probability of passing through into c becomes smaller, and almost all of hydrogen and oxygen in a radicalized state contribute to the water production reaction.

In addition, the entrance side reflector 9 and the filter 1
By providing the gas diffusion member 8 composed of 0 and the outlet side reflector / diffuser 12 in the reaction furnace main body, the platinum coating film 13 is not locally heated by the reaction heat, and the platinum coating film 13 is almost not heated. About 5
Moisture can be generated while being kept at a temperature of around 00 °, and safely and continuously 1000 cc / min with a high moisture generation reaction rate and responsiveness of over 99%.
It has been demonstrated that the above amount of water can be generated.

[0035]

EXAMPLE In the reaction furnace body 1 of FIG. 1, the outer dimensions of the furnace body members 2 and 3 are 134 mm in diameter and 33.5 m in thickness.
m of SUS316L, and the curved surfaces of the recesses 2a and 3a are curved surfaces with a radius of curvature R = 108 mm. In addition, as the filter 10, a filter (thickness of about 1.7 mm) having an average of 2.0 μm through holes, in which a plurality of stainless steel meshes were laminated, was used. Further, as the entrance side reflector 9, a case body 9a having an outer diameter of 22 mmφ and a height of 5 mm, and as the exit side reflector / diffuser 12 has a case body 12a having an outer diameter of 22 mmφ and a height of 10 mm. A filter having a through hole of 0.5 mm and an average of 70 μm in which the diffusion filter 12c is laminated with a plurality of stainless steel meshes (thickness: about 1.
7 mm) and a plurality of stainless meshes are laminated to have a filter having an average pore size of 200 μm (thickness: about 1.7 m).
m) was used. The platinum coating film 12d of the diffusion filter 12c is formed by forming a platinum film having a thickness of about 2 μm on a TiN barrier film having a thickness of about 2 μm.

On the other hand, as the platinum coating film 13, a TiN barrier film (thickness of about 2 μm, ion plating method) 13a is formed on the inner wall surface of the furnace body member 3, and platinum of about 1 μm thickness is formed thereon. Film (vacuum deposition method)
What formed 13b was used.

Using the above-mentioned water-generating reactor, H ₂ 1000 cc / min + O ₂ 100 from the gas supply passage 4a.
0 cc / min, H ₂ 1000 cc / min + O ₂ 5
00 cc / min, H ₂ 1500 cc / min + O ₂
The moisture generation reaction rate was obtained by supplying a raw material gas of 500 cc / min and actually measuring the moisture flowing out from the moisture gas outlet passage 5a. As a result, in any of the above cases, and in the continuous moisture generation test for about 10 hours, the moisture generation reaction rate of 99.3% or more was obtained.

[0038]

As described above, according to the present invention, an inlet side reflector, a filter and an outlet side reflector / diffuser are provided inside the reactor body, and a platinum coating film is provided inside the outlet side reflector / diffuser. A diffusion filter is provided.
As a result, the unreacted gas flowing into the moisture gas outlet passage becomes almost zero, and the high moisture generation reaction rate of 99.0% or more is obtained not only in the oxygen-rich source gas but also in the hydrogen-rich source gas. Is obtained. Further, the platinum coating film in the reaction furnace body is not locally heated by the reaction heat, and moisture of 1000 cc / min or more can be stably generated at a temperature of about 500 ° C.

According to the fourth aspect of the present invention, the reactor main body is formed by combining the furnace main body members having substantially the same shape so as to face each other. As a result, the structure of the reactor main body is simplified, and the manufacturing cost can be significantly reduced. The present invention has excellent practical utility as described above.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a reactor for a water generating device according to an embodiment of the present invention.

FIG. 2 is an enlarged vertical sectional view of an outlet-side reflector / diffuser.

3 is a cross-sectional view taken along the line EE of FIG.

FIG. 4 is a vertical cross-sectional view of a water generation reactor according to the prior application.

FIG. 5 is a curve showing a water generation reaction rate of a water generation reactor according to the prior application.

FIG. 6 is a curve showing a moisture generation reaction rate when the outlet side reflector is removed in the moisture generation reaction furnace of FIG. 4.

[Simple explanation of symbols]

1 is a reaction furnace main body, 1a is a space part, 2 is a furnace main body member, 2a
Is a recess, 2b is a flange, 2c is a gas supply passage, 3 is a furnace body member, 3a is a recess, 3b is a flange, 3c is a moisture gas outlet passage, 4 is a gas supply joint, and 4a is a gas supply passage. 5, reference numeral 5 is a water gas outlet joint, 5a is a water gas outlet passage, 6 is a filter flange, 7 is a reactor mounting bolt,
8 is a gas diffusion member, 9 is a reflector on the inlet side, 9a is a case body, 9b is a reflector, 9c is a through hole, 10 is a filter, 11
a / 11b is a filter retainer, 12 is an outlet side reflection / diffuser, 12a is a case body, 12b is a reflector, 12c is a diffusion filter, 12d is a platinum coating film, 12e is a through hole, 12f is a filter retainer, and 13 is platinum. A coating film, 13a is a barrier film, and 13b is a platinum film.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Kawada 2-3-2 Saibori, Nishi-ku, Osaka-shi, Osaka Prefecture Fujikin Co., Ltd. (72) Inventor Yoshikazu Tanabe 905-8 Shimotani, Iruma, Saitama Prefecture Person Shinichi Ikeda 2-3-2 Selling Moat, Nishi-ku, Osaka-shi, Osaka Prefecture Fujikin Co., Ltd. (72) Inventor Akihiro Morimoto 2-3-2 Selling Moat, Nishi-ku, Osaka City, Osaka Prefecture (72) Inventor Minami Yukio Fujikin Co., Ltd., 2-3-2, Nishibori, Nishi-ku, Osaka-shi, Osaka (56) Reference JP-A-1-205425 (JP, A) JP-A-54-150394 (JP, A) JP-A-54-40998 (JP, A) JP-A-55-41805 (JP, A) Actual Kaihei 1-165624 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 21/31 C01B 5 / 00

Claims (4)

(57) [Claims] 1. A reaction furnace body (1) which is formed by combining two furnace body members (2) and (3) and has a space (1a) therein; and one reactor body member (2) is drilled. A gas supply passage (2) which is installed and introduces a raw material gas into the space (1a).
c) and; Moisture gas outlet passage (3) which is bored in the other furnace body member (3) and leads out the generated water from the space (1a).
c) and; a cylindrical case body (9a) fixed to the space side of the furnace body member (2) coaxially with the gas supply passage (2c) and having a through hole (9c) in the wall surface, and a case body ( An inlet side reflector (9) comprising a reflector (9b) for closing the inner end surface of 9a); a filter (10) arranged in the space (1a) of the reactor body (1); Inside the case body (12a) and a cylindrical case body (12a) fixed to the space side of the furnace body member (3) coaxially with the moisture gas outlet passage (3c) and having a through hole (12e) in the wall surface. An outlet side reflection / diffusion body including a reflection plate (12b) closing the end face, a diffusion filter (12c) disposed inside the case body (12a), and a platinum coating film (12d) provided on the diffusion filter (12c). (12) and; Platinum coat provided on the inner wall surface of the reactor main body (1) Packaging film (13); generating moisture for reactor constructed from. 2. The reactor for generating water according to claim 1, wherein the filter (10) is a filter (10) having a through hole of 200 μm or less. 3. The water generating reactor according to claim 1, wherein the diffusion filter (12c) is a diffusion filter (12c) having a through hole of 50 μm or more. 4. A reactor body (1) having a curved surface-shaped recess (2a) and a furnace body member (3) having a curved surface-shaped recess (2a) having substantially the same shape. And 3) are formed so as to be opposed to each other, and both main body members (2) and (3) are formed.
The reactor for moisture generation according to claim 1, wherein the filter (10) is arranged in the central portion of the reactor.