JP3919988B2 - Liquid ozone production equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for supplying high-concentration ozone gas concentrated by liquefying ozone gas.
[0002]
[Prior art]
In recent years, the use of ozone (element symbol: O ₃ ) has been developed in various fields including water and sewage treatment using its strong oxidizing power. In particular, in the field of manufacturing semiconductor devices, application to Si wafer cleaning and TEOS-CVD (Tetra Ethyl Ortho Silicate-Chemical Vapor Deposition) is being studied. In Si wafer cleaning, ozone water in which ozone gas is dissolved in pure water is used as a cleaning liquid, and it has been announced that heavy metals and organic substances on Si wafer can be removed by using together with dilute hydrofluoric acid aqueous solution (electronic material 1999). March issue pp.13-18). TEOS-CVD is used to form an interlayer insulating film when a semiconductor device is formed into a multilayer wiring, and is characterized in that the unevenness of the wafer surface due to the electrode can be flattened by the insulating film. It has been reported that the planarization performance is improved by adding ozone to TEOS-CVD (Jpn. J. Appl. Phys. Vol. 32 (1993) pp. L110-L112).
[0003]
These are examples of using ozone gas with a relatively low concentration of about 10%, but by using ozone gas with a relatively high concentration of 80% or more, there is a possibility of a new application that could not be considered by conventional ozone gas use Has begun to be pointed out. As an example, there is formation of an oxide film of a Si semiconductor disclosed in JP-A-8-335576. According to this publication, it is possible to form an oxide film at a relatively low temperature, which is impossible with the conventional thermal oxidation method, and to form a high-quality oxide film with less suboxide layer and defect structure. Has been.
[0004]
By the way, a silent discharge system is generally used to generate ozone gas. This generates a mixed gas of ozone and oxygen from oxygen gas by electric discharge. Due to the limit of generation efficiency and the risk of explosion, it is difficult to generate ozone gas of about 10% by volume or more under normal temperature and normal pressure. It was. In view of this, Japanese Patent Publication No. 5-17164 introduces a method of generating high-concentration ozone gas of 80% or more by once liquefying and storing the generated ozone gas and then vaporizing it. This method is shown in FIG.
[0005]
As shown in FIGS. 4 and 5, the liquid ozone production apparatus is composed of an ozone gas generator and an exhaust device, and a liquid ozone generator for liquefying ozone. As shown in FIG. 4, oxygen gas is sent from the oxygen cylinder 3 to the ozonizer 5 through the pressure adjustment valve 4. In the ozonizer 5, the oxygen gas becomes an ozone-containing oxygen gas in which ozone gas is mixed with oxygen by silent discharge, and passes through a mass flow controller 6 for controlling the flow rate and a particulate removal filter 7 for removing particulates in the ozone-containing gas. It is introduced into a liquid ozone generator 2 that liquefies ozone gas.
[0006]
In the liquid ozone generator 2 of FIGS. 4 and 5, the ozone-containing oxygen gas obtained by mixing the ozone gas with the oxygen gas introduced from the ozone gas generator is converted into ozone through the flow rate adjusting valve 8 and the ozone-containing oxygen gas introduction pipe 25. It is introduced into the chamber 9. The ozone chamber 9 is thermally coupled to a cold head 19 that is cooled in advance by a refrigerator 20 that is driven by a compressor 21, and a temperature within 0.1 K is detected by a temperature sensor 24, a heater 23, and a temperature control device 22. The temperature can be precisely controlled with accuracy, and it is kept at a low temperature of 80K to 100K.
[0007]
The principle of liquefaction of ozone gas is to liquefy only ozone gas by the difference in vapor pressure between ozone and oxygen. For example, at 1 atmosphere, ozone has a boiling point of 161K, while oxygen has a boiling point of 90K. Therefore, if it is cooled to a temperature of 90K to less than 161K, most of ozone is in a liquid state and most of oxygen is in a gaseous state, so that only ozone can be separated as a liquid.
[0008]
Actually, since it is handled under reduced pressure conditions for safety against explosive properties of high-concentration ozone, the separation conditions are determined by the difference between the vapor pressures of ozone and oxygen under the temperature and pressure conditions. For example, if the temperature is 90K and the pressure is 10mmHg (= 13.3hPa), the vapor pressure of ozone at 90K is almost 0mmHg (= 0Pa), but oxygen is about 690mmHg (= 918hPa), and only ozone is under these conditions. Liquefied.
[0009]
Thus, in the ozone chamber 9, only ozone gas is liquefied by the difference in vapor pressure between ozone and oxygen at the cooled temperature. When the ozone gas is liquefied, the valve 15 between the oxidation treatment container 16 is closed and the valve 10 connected to the ozone killer 11 is opened. Oxygen gas that is not liquefied through the ozone discharge pipe 26 and the valve 10 connected to the ozone chamber 9 is introduced into the ozone killer 11 that is heated and converted into oxygen so that the remaining ozone gas is not discharged to the outside. A gas cooler 12 for cooling the heated oxygen gas and a liquid nitrogen trap 13 for preventing the ozone chamber from being contaminated or mixed with carbides from the vacuum pump 14 are discharged to the outside by the vacuum pump 14. .
[0010]
When the liquefied liquid ozone 27 is used for the purpose of oxidation or the like in the oxidation treatment container 16, the flow rate valve 8 and the valve 10 are closed and the valve 15 is opened. Liquid ozone is vaporized by raising the temperature of the ozone chamber 9 thermally coupled to the cold head 19 by the temperature sensor 24, the heater 23, and the temperature control device 22, and ozone gas is passed through the ozone discharge pipe 26 and the valve 15. It is introduced into the oxidation treatment container 16. The safety valve 18 is for expelling liquid ozone or high-concentration ozone gas.
[0011]
[Problems to be solved by the invention]
The explosion of ozone gas is a phenomenon in which ozone gas causes a rapid reaction and decomposes into oxygen. The decomposition reaction of ozone is expressed by the following two formulas.
[0012]
O ₃ + 24kcal → O ₂ + O (1)
O ₃ + O → 2O ₂ +94 kcal (2)
The above reaction takes place rapidly, resulting in an explosion. Even if a part of the exotherm of formula (2) is consumed to cause the reaction of formula (1), 94-24 = 60 kcal, that is, 30 kcal per mol of ozone gas. Since the heat capacity of oxygen gas is 7 cal / mol, ozone gas decomposes into about 1.5 times the oxygen gas, and the temperature of the decomposed oxygen gas rises by 60k / 7/3 = 2857 ° C. This is thought to cause the gas volume to expand rapidly and cause an explosion phenomenon.
[0013]
When this ozone gas explosion occurs in the chamber of the liquid ozone generator, the liquid ozone produced and accumulated in the lower part of the chamber also causes an explosion reaction. This is because liquid ozone has only 130 cal / cc of heat of evaporation, and liquid ozone becomes ozone gas at a stretch due to the heat generated by the explosion of ozone gas, causing the above explosive reaction.
[0014]
This abrupt reaction requires an energy source at first, and mainly contributes energy at the time of collision between ozone molecules. If the pressure of the ozone gas increases, the number of ozone molecules increases and the mean free path becomes shorter, so the energy that is inevitably generated increases and the explosion tends to occur. The collision probability 0 between ozone molecules is expressed as 0 (n!) As a function of the number of ozone molecules n. FIG. 6 shows the relationship between ozone gas pressure and explosion limit concentration. The temperature of ozone gas is calculated around 150K. It can be seen that as the atmospheric pressure approaches 1000 hPa, an explosion reaction occurs even with a relatively low concentration of ozone gas.
[0015]
In an actual chamber, since the pressure is controlled to be reduced and the ozone concentration of the ozone-containing oxygen gas introduced into the chamber is at most about 10%, an explosion reaction usually does not occur. Further, as is apparent from FIG. 7, the vapor pressure of liquid ozone is less than 100 Pa at a controlled liquid temperature of 80K to 100K, and therefore no explosion reaction occurs.
[0016]
However, this safety is lost when the capacity of the chamber for generating and storing liquid ozone is increased. This occurs because the temperature near the liquid surface center 29 of the liquid ozone 27 is relatively higher than the other portions, and this temperature difference increases as the chamber capacity increases. The temperature control of the liquid ozone is mainly performed by the cooling metal block 28 through the chamber wall surface.
[0017]
Thus, the temperature of the liquid ozone 27 near the wall of the chamber is controlled relatively well as the temperature of the cooling metal block 28, but the temperature of the liquid ozone in the other portions is the heat of the liquid ozone and the heat due to convection. Since it is performed by transmission, the temperature is higher than that of liquid ozone near the wall surface. In particular, the liquid ozone liquid surface that is in contact with the ozone-containing oxygen gas having a temperature relatively higher than the temperature controlled by the cooling metal block, and the temperature near the center farthest from the wall surface becomes the highest.
[0018]
As the chamber capacity increases, the distance from the wall surface to the center of the liquid surface naturally increases, so the temperature at the center of the liquid surface also increases. As the temperature rises, the vapor pressure rapidly increases as can be seen from FIG. In addition, if the amount of liquid ozone accumulated by increasing the chamber capacity increases, the explosion energy naturally increases.
[0019]
As described above, as the chamber capacity is increased and the amount of liquid ozone accumulated is increased, there is a problem that an ozone explosion is likely to occur and the energy of the explosion is increased. In order to prevent this, a method of lowering the control temperature of the chamber is conceivable. However, if the temperature is controlled to be lower than the above range, liquid oxygen is also generated, and the purity of the liquid ozone is lowered.
[0020]
Therefore, conventionally, there is a limit to the amount of liquid ozone that can be generated and stored, and specifically, about 0.5 cc is the maximum that has been put to practical use. Even when 0.5 cc of liquid ozone was vaporized, it became only 367 cc of high-concentration ozone gas at 1 atmosphere, which was completely insufficient for application to a mass production line of semiconductor devices.
[0021]
The present invention has been made in view of the above circumstances, and it is an object to provide a liquid ozone production apparatus capable of increasing the production / storage capacity of liquid ozone while maintaining safety against explosion of liquid ozone. To do.
[0022]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a first invention in which an ozone-containing gas is generated by ozonizing a gas containing oxygen, and the ozone-containing gas is introduced into a chamber through an introduction pipe. The lower part is cooled to liquefy and generate only ozone in the chamber, and ozone gas and oxygen gas that have not been liquefied out of the ozone-containing gas introduced into the chamber are exhausted from the chamber through an exhaust pipe. A safety valve that is opened above the pressure is connected, and a refrigerator is used as a means for cooling the lower part of the chamber. The cold head provided in the refrigerator and the lower part of the chamber are connected by a cooling metal block. In the device
The chamber is composed of a common chamber at the top and a plurality of divided chambers at the bottom, and both chambers are constructed integrally.
The plurality of divided chambers are temperature-controlled by a common refrigerator, cold head, cooling metal block,
An ozone-containing gas introduction pipe and an exhaust pipe are connected to the common chamber, and the introduction pipe controls the inflow and stop of the ozone-containing gas by an opening / closing means. The stop control is performed.
[0023]
In a second invention, the chamber is composed of a plurality of divided chambers,
The plurality of divided chambers are temperature-controlled by a common refrigerator, cold head, cooling metal block,
Each of the plurality of divided chambers is connected to an ozone-containing gas introduction pipe and an exhaust pipe,
The respective introduction pipes are unified on the upstream side of the ozone-containing gas, and the inflow and stop of the ozone-containing gas are controlled by opening / closing means provided in the unified part, and the respective exhaust pipes are also It is characterized in that the gas outflow and the stop are controlled by the opening / closing means provided in the integrated portion that is unified on the downstream side. In the third invention, the plurality of divided chambers are temperature-controlled by independent refrigerators, cold heads, cooling metal blocks,
Each of the introduction pipes is branched on the upstream side of the ozone-containing gas, and the inflow and stop of the ozone-containing gas are independently controlled by the opening / closing means provided in the branched portion,
Independent opening and closing means, safety valve, vacuum gauge is connected to each exhaust pipe,
In each of the divided chambers, generation of liquid ozone and generation of high-concentration ozone gas by overheating are performed independently and arbitrarily.
[0024]
According to a fourth aspect of the present invention, when liquid ozone generated and accumulated in the one divided chamber is heated to generate high-concentration ozone gas, liquid ozone is generated and accumulated in at least one of the other divided chambers. Adjust the amount of liquid ozone generated and accumulated in the other divided chambers and the number of divided chambers so that each divided chamber is heated, and the liquid ozone generation and accumulation mode and accumulated liquid ozone are heated in each divided chamber Then, the mode is switched to the mode for generating high-concentration ozone gas in order, and the apparatus is controlled so that the generation and accumulation of liquid ozone and the generation of high-concentration ozone gas can be performed continuously.
[0025]
The fifth invention is characterized in that each of the divided chambers is housed in an independent container.
[0026]
The sixth invention is characterized in that the opening / closing means of the pipe connected to each of the divided chambers is controlled so as to close at the time of the liquid ozone explosion, so that the other divided chambers are not affected by the explosion. Is.
[0027]
According to the seventh aspect of the present invention, shut-off control of the opening / closing means of the pipe connected to each divided chamber at the time of explosion of liquid ozone is performed by a signal when an explosion is detected by a vacuum gauge connected to the exhaust pipe. It is characterized by.
[0028]
The eighth invention is characterized in that the liquid ozone maximum accumulation amount in each of the divided chambers is set to 12 cc or less.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. In the present invention, a liquefied ozone production apparatus is constituted by a plurality of divided chambers, and the capacity of each divided chamber is sufficiently safe against explosion. It was below the value which can be kept. Embodiments will be described below.
[0030]
(First form)
FIG. 1 shows a first embodiment. The chamber 9 has an upper portion composed of a common chamber 91, and a lower portion composed of a plurality of divided chambers 9 a to 9 c, and the plurality of divided chambers 9 a to 9 c communicate with the common chamber 91. Lower ends of the plurality of divided chambers 9 a to 9 c are buried in a cooling metal block 28 that is a temperature control unit for liquefaction, and are connected to the refrigerator 20 via a cold head 19.
[0031]
In FIG. 1, ozone-containing oxygen gas is distributed from the common chamber 91 to the divided chambers 9a to 9c through the valve 8, and liquid ozone is generated and stored in the divided chambers 9a to 9c. The remaining mixed gas that has not been generated is exhausted through the valve 10. When the generated liquid ozone is used as the high-concentration ozone gas, the valves 8 and 10 are closed, the valve 15 is opened, the control temperature of the cooling metal block 28 is raised, and the liquid ozone is vaporized.
[0032]
If it does in this way, if the number of division | segmentation chambers is increased, the production | generation / accumulation amount of liquid ozone can be increased arbitrarily. In addition, since the maximum liquid ozone accumulation amount in each of the divided chambers 9a to 9c is a small capacity that is a certain value or less, liquid ozone explosion due to temperature rise near the center of the liquid level does not occur. The maximum liquid ozone accumulation amount value is described in the third form shown below. Specifically, it is preferably 10 cc or less.
[0033]
(Second form)
FIG. 2 shows a second embodiment. The second form is composed of a plurality of divided chambers 9a to 9c, and the cooling metal block 28, the cold head 19, and the refrigerator 20 which are temperature control units for liquefaction are common. The number of the divided chambers is the same as long as it is a plurality of two or more, but FIG.
[0034]
In FIG. 2, ozone-containing oxygen gas is distributed to the divided chambers 9 a to 9 c through the valve 8, and liquid ozone is generated and stored in the divided chambers 9 a to 9 c. The remaining mixed gas that has not been generated is exhausted through the valve 10. When the generated liquid ozone is used as the high-concentration ozone gas, the valves 8 and 10 are closed, the valve 15 is opened, the control temperature of the cooling metal block 28 is raised, and the liquid ozone is vaporized.
[0035]
If it does in this way, if the number of division | segmentation chambers is increased, the production | generation / accumulation amount of liquid ozone can be increased arbitrarily. In addition, since the maximum liquid ozone accumulation amount in each of the divided chambers 9a to 9c is a small capacity that is a certain value or less, liquid ozone explosion due to temperature rise near the center of the liquid level does not occur. The maximum liquid ozone accumulation amount value is described in the third form shown below. Specifically, it is preferably 10 cc or less.
(Third form)
A third embodiment is shown in FIG. Like the first and second embodiments, it is composed of a plurality of divided chambers 9a to 9c, but cooling metal blocks 28a to 28c, cold heads 19a to 19c, and refrigerators 20a to 20c, which are temperature control units for liquefaction. However, it is independent for each of the divided chambers 9a to 9c. Furthermore, valves 8a to 8c, 10a to 10b, 15a to 15c and safety valves 18a to 18c are also provided independently of each other. With this structure, generation and storage of liquid ozone and generation of high-concentration ozone gas from liquid ozone can be performed independently in each divided chamber by switching valves. Using this property, while generating high-concentration ozone gas from liquid ozone in one divided chamber, preliminary accumulation is performed so that generation / accumulation of liquid ozone is completed in one of the other divided chambers. If the number is prepared, it becomes possible to continuously generate high-concentration ozone gas, which was not possible with the conventional method.
[0036]
In FIG. 3, each of the divided chambers 9 a to 9 c is surrounded by containers 30 a to 30 c so that the impact at the time of explosion of a certain divided chamber does not affect the other divided chambers. In addition, you may use the vacuum insulation container which is not received to the influence of the temperature change outside a liquid ozone manufacturing apparatus as the containers 30a-30c. Further, the valves 8a to 8c, 10a to 10c, and 15a to 15c connected to the paths of the respective divided chambers 9a to 9c should be closed when the pressure detected by the vacuum gauges 17a to 17c exceeds a certain value. For example, the thermal shock at the time of explosion of a certain divided chamber can be prevented from entering another divided chamber. In addition to these, since the safety valves 18a to 18c are also provided independently in each of the divided chambers 9a to 9c, damage to the divided chambers 9a to 9c due to an explosion becomes independent in each divided chamber. So, even if a split chamber is damaged due to an explosion of liquid ozone due to an accident, the device can be repaired by replacing only the split chamber and parts such as a dedicated safety valve connected to the split chamber. Cost is low.
[0037]
However, as a premise of these, it is necessary to keep the maximum liquid ozone accumulation amount per divided chamber to a certain value or less to keep the explosion scale small. It is generally very difficult to consider the magnitude of the explosion theoretically and quantitatively.
[0038]
Therefore, the inventors conducted experiments for actually generating and accumulating liquid ozone and forcibly exploding, and empirically obtained the limit value. As explosion conditions, about 6 cc of liquid ozone was generated in a split chamber at 90K, the temperature of the cold head was raised to 150K, and then the liquid surface was irradiated with laser light for explosion.
[0039]
It was found that the damage to the inner wall of the divided chamber after the explosion was caused by burning the ozone-containing oxygen gas introduction pipe 25 in the middle of the inner part of the divided chamber, and the inner wall of the divided chamber that had been electropolished. As a result of this explosion experiment, the inside of the divided chamber was damaged to a point where it could not be repaired, but no damage was found outside the container surrounding the divided chamber. The inventors estimated that damage to the outside of the container surrounding the divided chamber started at least twice as much as 12 cc by analogy with the scale of this 6 cc explosion experiment. Therefore, if at least the maximum liquid ozone accumulation amount per division chamber is set to 12 cc or less, even if a division chamber breaks due to an explosion of liquid ozone, it prevents the damage to other division chambers from expanding. can do.
[0040]
【The invention's effect】
As described above, according to the present invention, by providing a plurality of divided chambers in the liquid ozone production apparatus, the capacity for generating and accumulating liquid ozone can be dramatically increased without sacrificing safety. it can. In addition, by providing temperature control units, safety valves, and valves associated with a plurality of divided chambers independently for each divided chamber, any of the other can be used while high concentration ozone gas is generated from liquid ozone in one divided chamber. Preliminary accumulation so that generation and accumulation of liquid ozone is completed in the divided chambers, and the number of divided chambers is prepared, so that it is possible to continuously generate high-concentration ozone gas that cannot be achieved by the conventional method. Furthermore, even if the split chamber is damaged by an explosion of liquid ozone due to an accident, the equipment can be repaired by replacing only the split chamber and parts such as a dedicated safety valve connected to the split chamber. Benefits such as lower costs are obtained.
[Brief description of the drawings]
FIG. 1 is a schematic configuration explanatory view showing a first embodiment of the present invention.
FIG. 2 is a schematic configuration explanatory view showing a second embodiment of the present invention.
FIG. 3 is a schematic configuration explanatory view showing a third embodiment of the present invention.
FIG. 4 is a schematic configuration explanatory diagram of a liquid ozone production apparatus.
FIG. 5 is a configuration explanatory view showing details of a liquid ozone generator in the liquid ozone production apparatus.
FIG. 6 is a characteristic diagram showing the relationship between ozone gas pressure and explosion limit concentration.
FIG. 7 is a characteristic diagram showing the relationship between the vapor pressure and temperature of liquid ozone.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Ozone gas generator and exhaust apparatus 2 ... Liquid ozone generator 8, 8a-8c ... Flow control valve 9 ... Chamber 9a-9c ... Divided chamber 10, 10a-10c ... Valve 15, 15a-15c ... Valve 17, 17a- 17c ... Vacuum gauge 18, 18a-18c ... Safety valve 19, 19a-19c ... Cold head 20, 20a-20c ... Refrigerator 28a-28c ... Cooling metal block 30a-30c ... Container 91 ... Common chamber

Claims (8)

A gas containing oxygen is ozonized to generate an ozone-containing gas, and this ozone-containing gas is introduced into the chamber through an introduction pipe, and the lower part of the chamber is controlled to cool and only ozone is liquefied into the chamber. Ozone gas and oxygen gas that were not liquefied out of the ozone-containing gas introduced into the chamber were exhausted from the chamber through an exhaust pipe, and a safety valve that was opened above a certain pressure was connected to the chamber and the lower part of the chamber was cooled In a device in which a refrigerator is used as means for performing the operation, the cold head provided in the refrigerator and the lower part of the chamber are connected by a cooling metal block,
The chamber is composed of a common chamber at the top and a plurality of divided chambers at the bottom, and both chambers are constructed integrally.
The plurality of divided chambers are temperature-controlled by a common refrigerator, cold head, cooling metal block,
The common chamber is connected to an ozone-containing gas introduction pipe and an exhaust pipe,
The introductory pipe controls the inflow and stop of ozone-containing gas by an opening / closing means, and the exhaust pipe also controls the outflow and stop of gas by the opening / closing means. In the liquid ozone manufacturing apparatus of Claim 1,
The chamber is composed of a plurality of divided chambers,
The plurality of divided chambers are temperature-controlled by a common refrigerator, cold head, cooling metal block,
Each of the plurality of divided chambers is connected to an ozone-containing gas introduction pipe and an exhaust pipe,
The respective introduction pipes are unified on the upstream side of the ozone-containing gas, and the inflow and stop of the ozone-containing gas are controlled by opening / closing means provided in the unified part, and the respective exhaust pipes are also An apparatus for producing liquid ozone, characterized in that control of gas outflow and stopping is performed by an opening / closing means provided in a unified portion on the downstream side. In the liquid ozone production apparatus according to claim 1 or 2,
The plurality of divided chambers are temperature controlled by independent refrigerators, cold heads, cooling metal blocks,
Each of the introduction pipes is branched on the upstream side of the ozone-containing gas, and the inflow and stop of the ozone-containing gas are independently controlled by the opening / closing means provided in the branched portion,
Independent opening and closing means, safety valve, vacuum gauge is connected to each exhaust pipe,
An apparatus for producing liquid ozone, wherein generation of liquid ozone and generation of high-concentration ozone gas by overheating are performed independently and arbitrarily in each of the divided chambers. In the liquid ozone manufacturing apparatus according to claim 3,
When liquid ozone generated and accumulated in the one divided chamber is heated to generate high-concentration ozone gas, generation and accumulation of liquid ozone is completed in at least one of the other divided chambers. The amount of liquid ozone generated and accumulated in the other divided chambers and the number of divided chambers are adjusted, and each divided chamber is heated to generate and accumulate liquid ozone and the accumulated liquid ozone. An apparatus for producing liquid ozone, wherein the apparatus is sequentially switched to a generating mode, and is controlled so that liquid ozone can be generated and accumulated as a whole, and high-concentration ozone gas can be generated continuously. In the liquid ozone production apparatus according to claim 3 and 4,
Each of the divided chambers is housed in an independent container. In the liquid ozone manufacturing apparatus according to claim 3, 4 and 5,
The apparatus for producing liquid ozone, wherein the opening / closing means of the pipe connected to each of the divided chambers is controlled so as to be closed at the time of liquid ozone explosion so as not to affect the other divided chambers. In the liquid ozone manufacturing apparatus according to claim 6,
The liquid characterized in that the shutoff control of the opening and closing means of the pipes connected to the respective divided chambers at the time of the explosion of liquid ozone is performed by a signal when an explosion is detected by a vacuum gauge connected to the exhaust pipe Ozone production equipment. In the liquid ozone manufacturing apparatus of Claim 1 to 7,
The liquid ozone production apparatus, wherein the maximum amount of liquid ozone accumulated in each of the divided chambers is set to 12 cc or less.

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