Ozone reduction device

Abstract

An ozone reduction device is provided. [Solution] The ozone reduction device 300 is for reducing ozone 110 from an ozone source 100 to oxygen gas 120. The ozone reduction device includes an inlet duct 10, a gas supply duct 20, a heating element 30, and an outlet duct 12. The inlet duct communicates with the ozone source. The gas supply duct introduces ozone from the ozone source via the inlet duct, and the gas supply duct transports the ozone via a spiral supply path P. The heating element provides thermal energy to heat the ozone transported to the gas supply duct, so that when the ozone flows along the spiral supply path, it receives thermal energy and is heated and reduced to oxygen gas. The outlet duct communicates with the gas supply duct and discharges the oxygen gas obtained by reducing the ozone.

Description

[Technical field]

[0001] The present invention relates to an ozone treatment technology, and more particularly to an ozone reduction device that rapidly reduces ozone to oxygen gas by heating. [Background technology]

[0002] Ozone can effectively clean the surface of semiconductor wafers (e.g., photoresist residues). In addition to cleaning, ozone can also grow an oxide layer that can be a passivation layer or interface layer for semiconductor devices. Ozone has very low stability and is easily decomposed into oxygen gas at room temperature, so it cannot be stored and is generally used on-site using an ozone generator to generate ozone for on-site use.

[0003] However, ozone is a gas that is harmful to humans and the environment, and although it can decompose into oxygen gas in the natural environment, this decomposition is very slow, so it requires further treatment before it can be discharged.

[0004] Current ozone reduction technology can decompose ozone into oxygen gas, but the half-life of ozone is about 3 days at 20 degrees Celsius, and the half-life decreases as the temperature increases. At a temperature of 250 degrees Celsius, the half-life is about 1.5 seconds. Therefore, the exhaust gas ozone decomposition device of the conventional ozone generator often adopts a method of decomposing ozone by heating. A typical ozone reduction technique includes two steps. The first step is to install a heating element in the ozone reduction chamber. The second step is to inject ozone into the ozone reduction chamber, where the heating element heats the ozone and reduces it to oxygen gas. However, since the conventional ozone reduction chamber is cylindrical, the time it takes for the ozone gas to pass through the cylindrical ozone reduction chamber is very short. In addition, in order to completely reduce the ozone to oxygen gas, the conventional technique requires heating at a very high temperature (about 420 degrees Celsius). Furthermore, the conventional ozone reduction technique requires that the ozone directly contacts the heating element, which is easily corroded. Summary of the Invention [Problem to be solved by the invention]

[0005] The main objective of the present invention is to provide an ozone reduction device that takes up less space than the conventional cylindrical ozone reduction chamber, has a larger heat transfer area, and can ensure sufficient time for heating the ozone molecules flowing into the spiral gas supply duct. [Means for solving the problem]

[0006] The ozone reduction device of the present invention is for reducing ozone from an ozone source to oxygen gas, and is characterized by comprising an inlet duct communicating with the ozone source, a gas supply duct through which ozone from the ozone source is introduced via the inlet duct and which transports the ozone along a spiral supply path, a heating element which provides thermal energy to heat the ozone transported by the gas supply duct, so that as the ozone flows along the spiral supply path, the ozone is heated by the thermal energy and reduced to oxygen gas, and an outlet duct communicating with the gas supply duct which discharges the oxygen gas obtained by reducing the ozone.

[0007] In the ozone reduction device according to the present invention, the gas supply duct is a spiral tube and is disposed on the heating element so as to have a spiral shape.

[0008] The ozone reduction device according to the present invention is characterized in that the gas supply duct is a spiral quartz tube and is located outside the heating element.

[0009] The ozone reduction device of the present invention is characterized in that the heating element directly heats the ozone in the gas supply duct, and also heats the ozone in the gas supply duct and the gas supply duct, and / or heats the gas supply duct, thereby indirectly heating the ozone in the gas supply duct.

[0010] The ozone reduction device of the present invention further includes an insulating element, which covers one or more of the gas supply duct, the heating element, the inlet duct and / or the outlet duct to maintain the heating temperature of the ozone.

[0011] The ozone reduction device of the present invention is characterized in that the heat insulating element is ceramic fiber heat insulating cotton.

[0012] The ozone reduction device of the present invention further includes a thermometer, which measures the heating temperature obtained by heating the ozone in the gas supply duct with the thermal energy from the heating element.

[0013] The ozone reduction device of the present invention further includes a temperature control element, which controls the thermal energy from the heating element based on the heating temperature measured by the thermometer, thereby heating the ozone to a predetermined temperature.

[0014] The ozone reduction device of the present invention further includes an inlet end adapter and an outlet end adapter, the inlet end adapter being arranged between the inlet duct and the gas supply duct and connected to both, and the outlet end adapter being arranged between the gas supply duct and the outlet duct and connected to both.

[0015] The ozone reduction device of the present invention is characterized in that the inlet end adapter and / or the outlet end adapter have a structure in which stainless steel is covered with Teflon (registered trademark).

[0016] The ozone reduction device of the present invention further includes a cooling device, which is provided in the outlet duct or between the gas supply duct and the outlet duct, and is characterized in that it reduces the temperature of the oxygen gas discharged from the gas supply duct.

[0017] In the ozone reduction device of the present invention, the heating element is a ceramic heating tube. Effect of the Invention

[0018] The ozone reduction device according to the present invention has the following advantages: (1) A spiral gas supply duct (e.g., a spiral quartz tube) is used as the ozone reduction chamber, which occupies less space than a conventional cylindrical ozone reduction chamber and has an increased heat conduction area, ensuring sufficient time for heating the ozone molecules flowing into the spiral gas supply duct.

[0019] (2) By fitting the spiral gas supply duct to the outside of the heating element, the heating element is located inside the spiral gas supply duct, thereby improving heating efficiency and reducing costs compared to conventional methods.

[0020] (3) Since a heat insulating element is used, the heating temperature can be made uniform and a rapid drop in temperature can be avoided.

[0021] (4) The spiral gas supply duct serves as the ozone reduction chamber, thereby avoiding the problem of ozone coming into direct contact with the heating element, which would corrode the heating element as in the conventional method.

[0022] (5) Since ozone gas can be rapidly reduced to oxygen gas, it is ideal for reducing a high flow rate of ozone gas.

[0023] In order to better understand the technical features and achievable technical effects of the present invention, better embodiments and detailed descriptions are provided below. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a schematic diagram showing an ozone reduction device according to the present invention. [Diagram 2] FIG. 1 is a schematic diagram showing the state in which the gas supply duct and heating element of the ozone reduction device of the present invention are combined, FIG. (I) is a schematic diagram showing the state before combination, and FIG. (II) is a schematic diagram showing the combined state. [Diagram 3] FIG. 2 is a schematic diagram showing an ozone reduction experiment device used in the ozone reduction device of the present invention. [Figure 4] FIG. 2 is a measurement diagram of an ozone reduction experiment of the ozone reduction device according to the present invention for 10 seconds. [Diagram 5] FIG. 2 is a 30-second measurement diagram of an ozone reduction experiment of the ozone reduction device of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Hereinafter, the embodiment of the present invention will be described with reference to the drawings. The ratio of each component in the drawings of the embodiment of the present invention is shown for easy understanding of the description, and is not the actual ratio. In addition, the dimensional ratio of the assembly shown in the drawings is for explaining each component and its structure, and the present invention is naturally not limited thereto. Meanwhile, for convenience of understanding, the same components in the following embodiments will be described with the same reference numerals.

[0026] Furthermore, the terms used throughout the specification and claims generally have their ordinary meanings as used in the art, in the context disclosed herein, and in the particular context, unless otherwise specified. Some of the terms used to describe the invention are explained below or elsewhere in this specification to provide those of ordinary skill in the art with additional guidance regarding the description of the invention.

[0027] The use of "first," "second," "third," etc. in this article is not intended to denote a specific order or sequence, nor is it used to limit the invention, but is merely used to distinguish between components or operations that are described with the same terminology.

[0028] Secondly, when terms such as "including," "comprising," "having," and "containing" are used in this article, they are all open terms, meaning including but not limited to.

[0029] Please refer to Figures 1 to 5. Figure 1 is a schematic diagram showing the ozone reduction device of the present invention. Figure 2 is a schematic diagram showing the state in which the gas supply duct and the heating element of the ozone reduction device of the present invention are combined, Figure (I) is a schematic diagram showing the state before combination, and Figure (II) is a schematic diagram showing the combined state. Figure 3 is a schematic diagram showing the ozone reduction experiment equipment used by the ozone reduction device of the present invention. Figure 4 is a 10-second measurement diagram of the ozone reduction experiment of the ozone reduction device of the present invention. Figure 5 is a 30-second measurement diagram of the ozone reduction experiment of the ozone reduction device of the present invention. The ozone reduction device 300 according to the present invention is for reducing ozone 110 from an ozone source 100 into oxygen gas 120. The ozone reduction device 300 according to the present invention includes an inlet duct 10, a gas supply duct 20, a heating element 30, and an outlet duct 12. The inlet duct 10 communicates with the ozone source 100 and introduces ozone 110 from the ozone source 100. The present invention does not limit the type or use of the ozone source 100. For example, the ozone 110 from the ozone source 100 is used for cleaning the surface of a semiconductor wafer, so the amount of ozone 110 introduced into the inlet duct 10 only accounts for a part of the ozone production amount of the ozone source 100, and is, for example, excess ozone.

[0030] The gas supply duct 20 introduces ozone from the ozone source 100 through the inlet duct 10. One of the features of the present invention is that the gas supply duct 20 transports ozone 110 along a spiral supply path P. The heating element 30 generates thermal energy to heat the ozone 110 transported by the gas supply duct 20, so that the ozone 110 receives thermal energy from the heating element 30 and is heated while flowing along the spiral supply path P (i.e., during the flow process) and is reduced to oxygen gas 120. In other words, in the present invention, the gas supply duct 20 having a hollow spiral structure is used as an ozone reduction chamber, so that the ozone 110 can perform the reduction step while flowing along the spiral supply path P inside the gas supply duct 20 and avoid contact with the heating element 30. The gas supply duct 20 is, for example, a spiral tube, and may be a spiral quartz tube, and the gas supply duct 20 is provided on the heating element 30 so as to have a spiral shape, for example fitting to the outside of the heating element 30.

[0031] The heating element 30 of the present invention is, for example, an electric heater such as a ceramic heating tube, but is not limited thereto, and the heating element 30 can be, for example, any conventional heater, such as a resistance heater, a heat exchange heater, etc. In the present invention, the ozone gas is transported through the spiral quartz tube, which can increase the contact area (i.e., the heat transfer area) between the ozone 110 and the quartz tube, and can ensure that the gas molecules of the ozone 110 flowing into the spiral quartz tube are heated for a sufficient heating time, so that the ozone 110 is sufficiently reduced to oxygen gas 120 during the process of flowing along the spiral supply path, i.e., before the ozone 110 flows out of the quartz tube. According to the present invention, ozone 110 can be quickly reduced to oxygen gas 120, which is suitable for reducing a large flow rate of ozone gas. Meanwhile, the present invention does not particularly limit the way of heating ozone 110, and the heating element 30 of the present invention may directly heat ozone 110, or simultaneously heat the gas supply duct 20 and the ozone 110 in the gas supply duct 20, and / or indirectly heat the ozone 110 in the gas supply duct 20 by heating the gas supply duct 20. These are determined by the material of the gas supply duct 20 and the heating type of the heating element 30.

[0032] The outlet duct 12 of the ozone reduction device 300 of the present invention communicates with the gas supply duct 20 and discharges the oxygen gas 120 obtained by reducing the ozone 110.

[0033] Meanwhile, the ozone reduction device 300 of the present invention further includes a heat insulating element 50. The purpose of the heat insulating element 50 is to ensure uniform heating temperature and avoid rapid temperature drop, so that the heat insulating element 50 can selectively cover appropriate locations or components, such as one or more of the gas supply duct 20, the heating element 30, the inlet duct 10 and / or the outlet duct 12. This can maintain the temperature at which the ozone 110 is heated, for example, the inside of the gas supply duct 20 can be maintained at a predetermined temperature. The predetermined temperature is, for example, a temperature at which the ozone 110 can be reduced to oxygen gas 120. The heat insulating element 50 of the present invention is, for example, but not limited to, ceramic fiber heat insulating cotton, and the heat insulating element 50 is not limited to a specific size or specification, as long as it can obtain the heat insulating and heat retaining effect, it is within the scope of the claims of the present invention. The above-mentioned predetermined temperature is, for example, 350 degrees Celsius, but the present invention is not limited to this. Since the half-life of ozone 110 is inversely proportional to temperature, the above-mentioned predetermined temperature is set, for example, to correspond to the length of the spiral supply path P and / or the flow rate of ozone 110. For example, if the length of the spiral supply path P is about 276 cm, the inner diameter of the gas supply duct 20 is about 4 mm, and the diameter of the spiral structure is about 50 mm, when the flow rate of ozone 110 is about 27 L / min, the residence time of ozone 110 in the gas supply duct 20 is about 77 ms. In other words, as long as the ozone 110 can fully reduce the ozone 110 to oxygen gas 120 before flowing out of the ozone reduction device 300 of the present invention, or can reduce the ozone 110 to oxygen gas 120 in a predetermined proportion, any specification of the gas supply duct 20 and the corresponding predetermined temperature are all within the scope of the present invention. The above-mentioned predetermined proportion is determined according to actual needs, and the present invention is not limited to a specific value. In addition, the residence time of the ozone 110 in the gas supply duct 20 is calculated by using a conventional equation for the relationship between speed-distance and time, and therefore the explanation thereof is omitted.

[0034] The ozone reduction device 300 according to the present invention further includes a thermometer 60 and / or a temperature control element 70. The thermometer 60 is for measuring the temperature obtained by heating the ozone 110 in the gas supply duct 20 with the thermal energy from the heating element 30. The temperature control element 70 is for controlling the thermal energy from the heating element 30 to heat the ozone 110. For example, the temperature control element 70 is electrically connected to the thermometer 60 and the heating element 30, and controls the thermal energy from the heating element 30 according to the temperature measured by the thermometer 60. This allows the ozone 110 to be heated to the above-mentioned predetermined temperature. The thermometer 60 is disposed, for example, on the central portion of the gas supply duct 20 to measure the heating temperature. The temperature control element 70 is disposed, for example, on the outside of the insulating element 50 to control the heating temperature of the ozone 110. The thermometer 60 and the temperature control element 70 according to the present invention may be, for example, a commercially available temperature sensor and temperature controller.

[0035] The ozone reduction device 300 according to the present invention further includes an inlet end adaptor 40 and an outlet end adaptor 42. The inlet end adaptor 40 is located between the inlet duct 10 and the gas supply duct 20 and connects them. The outlet end adaptor 42 is located between the gas supply duct 20 and the outlet duct 12 and connects them. The inlet end adaptor 40 and / or the outlet end adaptor 42 may have a structure in which stainless steel is covered with a Teflon material, but is not limited thereto, and may have a structure in which a stainless steel layer is covered around the Teflon layer.

[0036] The ozone reduction device 300 according to the present invention further includes a cooling device 72. The cooling device 72 can lower the temperature of the oxygen gas 120 discharged from the gas supply duct 20. The cooling device 72 is provided, for example, on the outlet duct 12 or between the gas supply duct 20 and the outlet duct 12. The cooling device 72 may be located in any position, and as long as it can obtain a cooling effect, it all falls within the scope of the present invention. The cooling device 72 is not limited to, for example, air cooling, liquid cooling, phase change, hybrid cooling, etc., and as long as it can lower the temperature of the oxygen gas 120, any type of cooling device 72 all falls within the scope of the present invention.

[0037] Please refer to Figures 3 to 5. Figure 3 is a schematic diagram of an ozone reduction experiment device used by the ozone reduction device 300 of the present invention. Figure 4 is a measurement diagram of an ozone reduction experiment of the present invention for 10 seconds. Figure 5 is a measurement diagram of an ozone reduction experiment of the present invention for 30 seconds. In the present invention, the ozone concentration sensor 84 measures the ozone concentration on both sides of the gas supply duct 20 (for example, the A measurement point and the B measurement point), respectively. This allows the result of ozone reduction by the ozone reduction device 300 of the present invention to be understood. To explain by way of example, the present invention takes the ozone source 100 as an ozone generator as an example, and supplies the pure oxygen gas 200 to the ozone generator by the high pressure liquid phase oxygen gas cylinder 80 to provide the ozone 110. In addition, in the present invention, before the ozone 110 flows into the gas supply duct 20 of the ozone reduction device 300, for example, the gas supply duct 20 is first heated to a high temperature by the temperature control element 70, and when the thermometer 60 reaches, for example, about 350 degrees Celsius, the ozone 110 flows into the gas supply duct 20 of the ozone reduction device 300 via the inlet duct 10. In detail, ozone 110 flows into the gas supply duct 20 through the inlet end adapter 40, and the temperature of the gas supply duct 20 is about 350 degrees Celsius. After passing through the gas supply duct 20 at 350 degrees Celsius, the ozone 110 flows into the outlet duct 12 through the outlet end adapter 42. The reduced gas passes through the cooling device 72, and the ozone concentration (measurement point B) is measured again by the ozone concentration sensor 84, and then discharged. In the present invention, for example, the flow rate of the oxygen gas 200 is controlled to be 27 L / min by the mass flow controller 82 (or referred to as Mass Flow Controller), and the back pressure is controlled to be 30 Psi (pounds per square inch) by the pressure controller 86. The ozone reduction device 300 according to the present invention is installed on, for example, a workbench 310, and an ozone reduction experiment is performed, but is not limited thereto.

[0038] Referring to Fig. 4, according to the data shown in Fig. 4, when the ozone concentration at measuring point A increases rapidly from 0.02wt% to 0.14wt%, the ozone reduction device 300 of the present invention can reduce 0.14wt% ozone to 0.01wt% (measuring point B) in less than 1 second.

[0039] Please refer to Fig. 5. Fig. 5 shows data obtained by continuously performing ozone reduction reaction by the ozone reduction device 300 of the present invention and simultaneously measuring ozone concentration (measurement point A and measurement point B) for 30 minutes. From Fig. 5, it can be seen that the ozone reduction device 300 of the present invention can still maintain good reactivity even under long-term operation.

[0040] In the above ozone reduction experiment, the flow rate of ozone 110 from the ozone source 100 is about 27 L / min, and the ozone concentration is about 15.3 wt% (measurement point A), which corresponds to about 354 g / hour of ozone generation. The ozone concentration is more than three times that of general space disinfection and sterilization. In this invention, the gas supply duct 20 (e.g., a spiral quartz tube) can heat the ozone 110 for a sufficient period of time, and the ozone 110 can be quickly reduced to oxygen gas 120 (almost no ozone 110 can be detected at measurement point B). In addition, the present invention uses a heat insulating element 50 (e.g., a heat insulating material layer), so that ozone reduction can be performed stably for a long period of time.

[0041] The ozone reduction device according to the present invention has the following effects: (1) A spiral gas supply duct (e.g., a spiral quartz tube) is used as the ozone reduction chamber, which occupies less space than a conventional cylindrical ozone reduction chamber and has an increased heat conduction area, ensuring sufficient time for heating the ozone molecules flowing into the spiral gas supply duct.

[0042] (2) By fitting the spiral gas supply duct to the outside of the heating element, the heating element is located inside the spiral gas supply duct, thereby improving heating efficiency and reducing costs compared to conventional methods.

[0043] (3) Since a heat insulating element is used, the heating temperature can be made uniform and a rapid drop in temperature can be avoided.

[0044] (4) The spiral gas supply duct serves as the ozone reduction chamber, thereby avoiding the problem of ozone coming into direct contact with the heating element, which would corrode the heating element as in the conventional method.

[0045] (5) Since ozone gas can be rapidly reduced to oxygen gas, it is ideal for reducing a high flow rate of ozone gas.

[0046] The above description is illustrative only and not limiting. Any equivalent modifications or alterations thereto that do not depart from the spirit and scope of the present invention are within the scope of the claims. [Explanation of symbols]

[0047] 10 Inlet Duct 12 Exit duct 20 Gas supply duct 30 Heating element 40 Inlet end adapter 42 Outlet end adapter 50 Thermal Insulation Element 60 thermometer 70 Temperature control element 72 Cooling device 82 Mass Flow Controller 84 Ozone concentration sensor 100 Ozone Source 110 Ozone 120 Oxygen gas 200 Oxygen gas 300 Ozone reduction device 310 Workbench P Spiral feed path A,B measurement points

Claims

1. 1. An ozone reduction device for reducing ozone from an ozone source to oxygen gas, comprising: an inlet duct in communication with the ozone source; a gas supply duct through which the ozone from the ozone source is introduced via the inlet duct and which transports the ozone along a helical supply path; a heating element for providing thermal energy to heat the ozone transported through the gas supply duct, so that the ozone is heated by the thermal energy and reduced to oxygen gas as it flows along the spiral supply path; an outlet duct communicating with the gas supply duct and discharging the oxygen gas obtained by reducing the ozone, Ozone reduction device.

2. 2. The ozone reduction device according to claim 1, wherein the gas supply duct is a spiral tube and is provided on the heating element so as to have a spiral shape.

3. 2. The ozone reduction device according to claim 1, wherein the gas supply duct is a spiral quartz tube and is provided outside the heating element.

4. 2. The ozone reduction device according to claim 1, wherein the heating element directly heats the ozone in the gas supply duct, and indirectly heats the ozone in the gas supply duct by heating the gas supply duct and the ozone in the gas supply duct and / or by heating the gas supply duct.

5. 2. The ozone reduction device according to claim 1, further comprising an insulating element, the insulating element covering one or more of the gas supply duct, the heating element, the inlet duct and / or the outlet duct to maintain the heating temperature of the ozone.

6. 6. The ozone reducing device according to claim 5, wherein the heat insulating element is ceramic fiber heat insulating cotton.

7. 2. The ozone reduction device according to claim 1, further comprising a thermometer, the thermometer measuring a heating temperature obtained by heating the ozone in the gas supply duct with the thermal energy from the heating element.

8. The ozone reduction device according to claim 7, further comprising a temperature control element, the temperature control element controlling the thermal energy from the heating element according to the heating temperature measured by the thermometer, thereby heating the ozone to a predetermined temperature.

9. 2. The ozone reduction device according to claim 1, further comprising an inlet end adaptor and an outlet end adaptor, the inlet end adaptor being provided between the inlet duct and the gas supply duct and connected to both, and the outlet end adaptor being provided between the gas supply duct and the outlet duct and connected to both.

10. The ozone reduction device according to claim 9, wherein the inlet end adapter and / or the outlet end adapter has a structure in which stainless steel is covered with Teflon (registered trademark).

11. 2. The ozone reduction apparatus according to claim 1, further comprising a cooling device, the cooling device being provided in the outlet duct or between the gas supply duct and the outlet duct, and reducing a temperature of the oxygen gas discharged from the gas supply duct.

12. 2. The ozone reduction device according to claim 1, wherein the heating element is a ceramic heating tube.

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