High-purity ozone collecting device and collecting method thereof

Abstract

The invention discloses a high-purity ozone collecting device and method, the device adopts a passivated stainless steel distillation tube as a collecting container, the interior of the device is divided into a layered structure by a sheet, and the device is filled with a mixed adsorption medium; according to the high-purity ozone collecting device, the working temperature of the device is accurately regulated and controlled through the temperature regulation and control assembly, ozone collecting operation is achieved, the high-purity ozone collecting device has the advantages of being capable of improving the purity and the collecting amount of collected ozone, and therefore the oxidation performance of various devices mainly including film growth devices can be effectively enhanced.

Description

Technical Field

[0001] The invention relates to an ozone collecting device, and in particular to a high-purity ozone collecting device and a collecting method thereof. Background Art

[0002] In the field of modern materials science, the ability to prepare high-purity ozone has evolved into a crucial core element, which is of great significance for the preparation of high-quality oxide materials and the advancement of semiconductor manufacturing processes. With its super strong oxidation ability, high-purity ozone can accelerate the reaction process of deposited atoms or molecules, and promote their more efficient diffusion and rearrangement on the substrate surface: this not only improves the crystallinity and density of the film, and significantly improves its crystal quality; but also the faster growth rate provides strong support for the improvement of industrial production efficiency. At the same time, high-purity ozone can greatly reduce the activation energy of the reaction, and can achieve harsh oxidation reactions under low temperature conditions and high vacuum environments, opening up a new path for the preparation of temperature-sensitive materials and oxide materials with harsh oxidation states. On the other hand, the preparation of high-purity ozone plays a key role in the cleaning and etching processes of semiconductor manufacturing processes, and has played an indispensable role in promoting the refinement and efficiency of semiconductor manufacturing processes. The precise preparation of high-purity ozone is not only an important part of materials science research, but also the key to ensuring the successful synthesis of high-quality oxide materials. At the same time, this preparation capability has played an indispensable role in promoting the refinement and efficiency of semiconductor manufacturing processes. As an important part of the field of materials science, high-purity ozone has shown great potential and value in promoting scientific and technological progress and enhancing industrial competitiveness. However, the ozone purification and collection devices currently on the market have the defects of low ozone collection volume and collection purity, which not only affects the performance of oxide materials, but also hinders the development of semiconductor chip manufacturing processes. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a high-purity ozone collection device that can significantly improve the purity and collection amount of collected ozone; another purpose of the present invention is to provide a method for collecting high-purity ozone using this device.

[0004] Technical solution: The high-purity ozone collection device described in the present invention includes a sleeve, a distillation tube with an air inlet pipe and an exhaust pipe arranged in the sleeve, and a temperature control component. The air inlet pipe is connected to the ozone generator. There is a sealed cavity between the distillation tube and the sleeve. The distillation tube is a passivated stainless steel distillation tube. The air inlet pipe of the distillation tube extends into the bottom of the distillation tube but does not touch it, and the inner cavity is provided with a layered distribution structure and a mixed adsorption medium.

[0005] Preferably, the layered distribution structure is composed of one or more thin sheets with a plurality of air holes, which are used to disperse the airflow so that it can contact the mixed adsorption medium more fully, thereby achieving more efficient cooling and ozone adsorption.

[0006] Preferably, the mixed adsorption medium is composed of two or more materials, including a medium with good thermal conductivity and a porous adsorption medium, and the mixed adsorption medium is inert to ozone reaction. The synergistic effect of the two ensures the overall temperature uniformity of the adsorption medium and improves the ozone adsorption efficiency.

[0007] Preferably, the heating wire is wrapped in flexible rubber and insulating glue, which can not only provide insulation protection, enhance structural strength, and improve heating efficiency, but also be waterproof and moisture-proof, ensuring the safe, stable and efficient operation of the heating wire.

[0008] Preferably, the outer wall of the sleeve adopts a three-layer insulation structure of tin foil, thermal insulation cotton and tin foil, which can reduce the heat exchange between the external environment and the distillation tube, improve the thermal insulation performance, and reduce the loss of liquid nitrogen.

[0009] Preferably, the sealed cavity is filled with nitrogen, and the pressure in the sealed cavity is slightly higher than the external environment, thereby ensuring a dry positive pressure environment and preventing condensed water in the air from short-circuiting the temperature control components during the cooling process.

[0010] Preferably, the ozone generator is a high-voltage discharge ozone generator, and oxygen is decomposed by the ozone generator under the action of a high-voltage electric field to generate oxygen plasma, thereby generating an oxygen-ozone mixed gas.

[0011] The method for collecting ozone using the above-mentioned device of the present invention comprises the following steps:

[0012] S1: Connect the mixed gas of oxygen and ozone generated by the ozone generator to the bottom of the passivated stainless steel distillation tube through the air inlet pipe;

[0013] S2: Control the temperature control component to keep the temperature of the passivated stainless steel distillation tube between -145°C and -135°C;

[0014] S3: The high thermal conductivity medium in the mixed adsorption medium cools the mixed gas, and part of the ozone is liquefied and adsorbed and collected by the porous medium;

[0015] S4: After the ventilation is completed, an external vacuum pump removes part of the gaseous oxygen adsorbed by various media in the inner cavity of the passivated stainless steel distillation tube to purify the collected ozone;

[0016] S5: Conduct purity test on the collected ozone.

[0017] Preferably, the detection in step S5 comprises the following steps:

[0018] S5.1: Control the temperature control assembly to raise the temperature of the passivated stainless steel distillation tube to -125°C -115°C;

[0019] S5.2: The collected high-purity ozone releases gaseous ozone under negative pressure and temperature increase, and the gaseous ozone is introduced into the growth chamber of the oxide material growth process through an exhaust pipe for purity detection.

[0020] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: by adopting a passivated stainless steel distillation tube and arranging a layered distribution structure and a mixed adsorption medium in its inner cavity, the purity and collection amount of collected ozone are improved and the oxidation capacity is enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the high-purity ozone collection device in the present invention.

[0022] Figure 2 This is a schematic diagram of the structure of the passivated stainless steel distillation tube of the high-purity ozone collection device in the present invention. DETAILED DESCRIPTION

[0023] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0024] Example 1

[0025] like Figure 1As shown, a high-purity ozone collection device and collection method in this embodiment, the device mainly consists of a sleeve 1 with a hollow inner tube wall and a cavity inside, and a distillation tube 4 inside the sleeve; the distillation tube 4 adopts a passivated stainless steel distillation tube that has been passivated with concentrated sulfuric acid, and a dense metal oxide layer is present on its surface after the treatment. The high mechanical strength of the stainless steel ensures the air tightness of the distillation tube 4 at different working temperatures. The dense metal oxide layer on the surface obtained by the passivation treatment can avoid the generation of oxide debris and the consumption of ozone in the distillation tube 4 during the collection process; a sealed cavity is formed between the passivated stainless steel distillation tube 4 and the sleeve 1, and nitrogen is filled in the sealed cavity. The pressure in the sealed cavity is slightly higher than the external environment, which is a positive pressure state. A dry environment is ensured, and condensed water in the air is prevented from short-circuiting the temperature control component 5 during the cooling process; an air inlet pipe 2 and an exhaust pipe 3 are set on the passivated stainless steel distillation tube 4, the air inlet pipe 2 is used to connect the ozone generator, and the exhaust pipe 3 is used to connect the vacuum pump or other devices, and a layered distribution structure 6 and a mixed adsorption medium 7 are provided inside the distillation tube 4; the layered distribution structure 6 is composed of one or more thin sheets with a plurality of pores, which are used to disperse the airflow so that it can be more fully in contact with the mixed adsorption medium to achieve more efficient cooling and ozone adsorption; the mixed adsorption medium 7 is composed of two or more materials, including a medium with good thermal conductivity and a porous adsorption medium, and the mixed adsorption medium 7 has ozone reaction inertness. The synergistic effect of the two ensures the overall temperature uniformity of the adsorption medium and improves the ozone adsorption efficiency. The temperature in the device is controlled by a temperature control component 5, which is composed of a heating wire 8 used as a heat source and uniformly wound on the wall of the distillation tube 4, and a liquid nitrogen layer 9 used as a cold source in the interlayer of the sleeve 1; at the same time, the heating wire 8 is wrapped between the flexible rubber and the insulating rubber, which can not only provide insulation protection, enhance structural strength, and improve heating efficiency, but also be waterproof and moisture-proof, ensuring the safe, stable and efficient operation of the heating wire. At the same time, in order to reduce the heat exchange between the external environment and the distillation tube 4, improve the thermal insulation performance, and reduce the loss of liquid nitrogen, the outer wall of the sleeve 1 adopts a three-layer insulation structure of tin foil, thermal insulation cotton, and tin foil.

[0026] The operation process of the whole device is as follows: the mixed gas of oxygen and ozone generated by the high-voltage discharge ozone generator 10 is connected to the air inlet pipe 2 and introduced into the bottom of the distillation tube 4, and the temperature control component 5 is controlled to make the temperature of the distillation tube 4 between the boiling point of ozone and the boiling point of oxygen, that is, between -111°C and -183°C. The difference between the boiling points of ozone and oxygen is utilized to separate ozone and oxygen through the ozone collection device, and the high thermal conductivity medium in the mixed adsorption medium 7 cools the mixed gas, and the ozone is liquefied and adsorbed and collected by the porous medium. After the ventilation is completed, the external vacuum pump is connected to the exhaust pipe 3 to extract part of the gaseous oxygen adsorbed by various media in the inner cavity of the distillation tube 4, and the collected ozone is purified. The ozone remains in the distillation tube 4 in a liquid state, and the oxygen is extracted, and then the concentration of the ozone in the distillation tube 4 is detected.

[0027] Example 2

[0028] The ozone collected by this device is introduced into chambers with different total pressures to obtain different ozone partial pressure values, and the collection time is 8 minutes. It should be noted that the mixed gas of ozone and oxygen obtained by the ozone generator is directly introduced into the growth chamber, and the obtained ozone partial pressure value is generally lower than the detection limit (1E-9Torr) of the residual gas analyzer (RGA).

[0029] Table 1 Ozone partial pressure content detected by residual gas analyzer RGA under different chamber pressures

[0030] Total cavity pressure (Torr) Total ozone pressure (Torr) Ozone share 2.50E-06 1.78E-08 0.71％ 4.40E-06 5.50E-08 1.25％ 4.80E-06 8.60E-08 1.79％ 5.40E-06 1.27E-07 2.35％ 6.10E-06 1.60E-07 2.62％ 6.80E-06 2.01E-07 2.96％ 8.60E-06 2.83E-07 3.29％

[0031] Example 3

[0032] This embodiment provides a high-purity ozone collection device composed of a single medium. The specific operation steps are basically the same as those in Example 1, with the main differences being that the distillation tube is made of glass and lacks a mixed adsorption medium and a distillation tube lumen with a layered distribution structure.

[0033] The collected ozone was introduced into the growth chamber. Under the same back pressure (8.6E-6Torr), the ozone content measured by RGA was 9.0E-9Torr, and the ozone partial pressure accounted for 0.1%. However, after the equipment was run for many times, the distillation tube broke and the negative pressure could not be maintained. Reasonable analysis shows that a single adsorption medium with poor thermal conductivity requires a wider operating temperature range and a longer adsorption collection time (60min), while the glass distillation tube will fatigue and break due to frequent thermal expansion and contraction after experiencing multiple heating and cooling cycles. To this end, it is necessary to use materials with high mechanical strength and fatigue resistance to make the distillation tube to solve the problem of material fatigue and rupture caused by frequent thermal expansion and contraction; at the same time, it is necessary to add a medium with high thermal conductivity to improve the overall thermal conductivity of the device, narrow the working temperature window to ensure that the distillation tube works efficiently in a stable temperature environment, and improve the overall performance and life of the device.

[0034] Example 4

[0035] This embodiment provides a high-purity ozone collection device composed of a mixed adsorption medium. The specific operation steps are basically the same as those in Example 1, with the main difference being that there is no inner cavity of the distillation tube with a layered distribution structure.

[0036] The collected ozone was passed into the growth chamber. After the equipment was run for many times, under the same back pressure (8.6E-6Torr), the ozone content measured by RGA was only 5.8E-9Torr, and the ozone partial pressure accounted for only 0.067%. After disassembling the device, it was found that the originally evenly dispersed mixed adsorption medium had been stratified: the silica gel balls were arranged in the upper layer; the alumina flakes were in the lower layer. Reasonable analysis shows that after multiple cycles of ozone collection and distillation, the relatively light silica gel balls gradually migrated upward under the action of airflow; while the heavier alumina flakes settled under the action of gravity. In the case of this mixed medium stratified distribution, when the ozone-oxygen mixed gas at room temperature is passed into the distillation tube, the alumina flakes with high thermal conductivity in the lower layer cannot efficiently adsorb part of the liquefied ozone; the silica gel balls with low thermal conductivity in the upper layer have a relatively high temperature, and the adsorption capacity of the surface active sites for ozone molecules is significantly reduced. In this embodiment, the lack of a layered distribution structure prevents the mixed adsorption medium from being evenly distributed in the device, resulting in temperature differences between different medium layers, causing the overall efficiency of the device to be at a low level and unable to meet the performance requirements of actual application scenarios.

Claims

1. A high-purity ozone collection device, comprising a sleeve (1), a distillation tube (4) provided in the sleeve (1) and having an air inlet pipe (2) and an air outlet pipe (3), and a temperature control component (5), wherein the air inlet pipe (2) is connected to an ozone generator (10), and a sealed cavity is formed between the distillation tube (4) and the sleeve (1), characterized in that: The distillation tube (4) is a passivated stainless steel distillation tube, the air inlet pipe (2) of the distillation tube (4) extends into the bottom thereof but does not touch it, and the inner cavity is provided with a layered distribution structure (6) and a mixed adsorption medium (7).

2. The ozone collecting device according to claim 1, characterized in that: The layered distribution structure (6) is composed of one or more thin sheets with a plurality of air holes.

3. The ozone collecting device according to claim 1, characterized in that: The mixed adsorption medium (7) is composed of two or more materials, including a medium with good thermal conductivity and a porous adsorption medium, and the mixed adsorption medium (7) is inert to ozone reaction.

4. The ozone collecting device according to claim 1, characterized in that: The sleeve (1) is a hollow sandwich structure, and the temperature control component (5) is composed of a heating wire (8) used as a heat source and uniformly wound on the wall of the distillation tube (4) and a liquid nitrogen layer (9) used as a cold source in the interlayer of the sleeve (1).

5. The ozone collecting device according to claim 4, characterized in that: The heating wire (8) is wrapped in flexible rubber and insulating glue.

6. The ozone collecting device according to claim 5, characterized in that: The outer wall of the sleeve (1) adopts a three-layer heat insulation structure of tin foil, heat insulation cotton and tin foil.

7. The ozone collecting device according to claim 1, characterized in that: The sealed cavity is filled with nitrogen, and the pressure inside the sealed cavity is in a positive pressure state.

8. The ozone collecting device according to claim 1, characterized in that: The ozone generator (10) is a high-voltage discharge ozone generator.

9. A method for collecting ozone using the device according to claims 1-8, characterized in that: The following steps are involved: S1: Connecting the mixed gas of oxygen and ozone generated by the ozone generator (10) to the air inlet pipe (2) and introducing it into the bottom of the distillation tube (4); S2: Control the temperature control component (5) to make the temperature of the distillation tube (4) between -145°C and -135°C; S3: The high thermal conductivity medium in the mixed adsorption medium (7) cools the mixed gas, and part of the ozone is liquefied and adsorbed and collected by the porous medium; S4: After the ventilation is completed, an external vacuum pump removes part of the gaseous oxygen adsorbed by various media in the inner cavity of the distillation tube (4) to purify the collected ozone; S5: Conduct purity test on the collected ozone.

10. The ozone collection method according to claim 9, characterized in that: The detection of step S5 comprises the following steps: S5.1: Control the temperature control component (5) to raise the temperature of the distillation tube (4) to -125°C to -115°C; S5.2: The collected high-purity ozone is released into gaseous ozone under negative pressure and temperature increase, and the gaseous ozone is introduced into the growth chamber of the oxide material growth process through the exhaust pipe (3) for purity detection.

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