Pneumatic PCW emergency cooling water circulation system

Abstract

The utility model discloses a pneumatic PCW emergency cooling water circulation system which comprises a storage tank, a vaporizer and a water tank assembly. The storage tank is used for storing a phase-change material; the vaporizer comprises a shell and a heat exchanger arranged in the shell, and the shell is connected with the storage tank through a liquid conveying pipe; the water tank assembly comprises a water tank and a heat exchanger arranged in the water tank, the upper part of the water tank is connected with the shell through an air inlet pipe, and the lower part of the water tank is connected with the crystal growth furnace through a process cooling water pipe; the heat exchangers are connected through a water inlet pipe and a water return pipe to form a water circulation loop; wherein the phase-change material can absorb heat of the heat exchanger to be vaporized, compared with the prior art, process cooling water circulation of the crystal growth furnace under the condition of sudden power failure is ensured, temperature controllability of the crystal growth furnace is ensured, cooling capacity released when the phase-change material is vaporized participates in the cooling process of the process cooling water, the energy utilization efficiency is improved, and the service life of the crystal growth furnace is prolonged. And meanwhile, the cooling efficiency and stability of the system are improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing technology, and in particular to a pneumatic PCW emergency cooling water circulation system. Background Art

[0002] As a representative of the third-generation semiconductor materials, silicon carbide (SiC) has the characteristics of wide bandgap, high breakdown electric field, high thermal conductivity, and high saturated electron mobility. Therefore, semiconductor devices made of silicon carbide materials are suitable for high voltage, high current, high temperature, high frequency and other scenarios, and have broad prospects.

[0003] Silicon carbide crystal growth equipment is an important equipment for preparing silicon carbide crystals. Since the silicon carbide crystal preparation process requires a high temperature environment, silicon carbide crystal growth equipment is usually equipped with a cooling water system to cool the equipment.

[0004] At present, the cooling water system of silicon carbide crystal growth equipment uses the process cooling water system (PCW) as its water source, and PCW is generally powered by an external power source such as the mains, and the process cooling water is circulated through an electric pump. Therefore, once a power outage occurs, the PCW will not work properly, causing the crystal growth furnace equipment to be unable to be cooled and the temperature to rise sharply, resulting in uncontrollable risks. Utility Model Content

[0005] The purpose of the present application is to provide a pneumatic PCW emergency cooling water circulation system to ensure the process cooling water circulation of the crystal growth furnace in the event of a sudden power outage, thereby ensuring that the temperature of the crystal growth furnace is controllable.

[0006] The embodiments of the present application can be implemented as follows:

[0007] In a first aspect, the utility model provides a pneumatic PCW emergency cooling water circulation system, including a storage tank, a vaporizer, and a water tank assembly;

[0008] The storage tank is used to store phase change material;

[0009] The vaporizer comprises a shell and a heat exchanger disposed in the shell, and the shell is connected to the storage tank via a liquid infusion tube;

[0010] The water tank assembly includes a water tank and a heat exchanger arranged in the water tank, the upper part of the water tank is connected to the shell through an air inlet pipe, and the lower part of the water tank is used to connect the crystal growth furnace through a process cooling water pipe; the heat exchanger is connected to the heat exchanger through a water inlet pipe and a water return pipe to form a water circulation loop;

[0011] The phase change material can absorb the heat of the heat exchanger and vaporize.

[0012] In an optional embodiment, the pneumatic PCW emergency cooling water circulation system includes two water tank assemblies, wherein the water tank of one of the water tank assemblies serves as an outlet tank for supplying cooling water to the crystal growth furnace, and the water tank of the other water tank assembly serves as a return tank for recovering cooling water that is heated by absorbing heat from the crystal growth furnace.

[0013] In an optional embodiment, both of the two intake pipes are provided with an intake valve, and the intake valves on the two intake pipes can be opened selectively.

[0014] In an optional embodiment, the water tank is at least partially made of a transparent material and is provided with water level markings.

[0015] In an optional embodiment, the air intake pipe is provided with a pressure regulating valve.

[0016] In an optional embodiment, the infusion tube is provided with a switch valve.

[0017] In an optional embodiment, the water inlet pipe or the water return pipe is provided with a pneumatic pump.

[0018] In an optional embodiment, the housing is connected to the pneumatic pump via an air supply pipe.

[0019] In an optional embodiment, the water tank is provided with an exhaust valve.

[0020] In an optional embodiment, the phase change material is liquid nitrogen.

[0021] Compared with the prior art, the beneficial effects of the embodiments of the present application include, for example:

[0022] After the liquid phase change material in the storage tank is input into the shell through the liquid infusion pipe, it is vaporized by absorbing the heat of the heat exchanger. The gaseous phase change material enters the upper area of ​​the water tank through the air inlet pipe to exert pressure on the process cooling water in the water tank, forcing the process cooling water to be transported to the crystal growth furnace through the process cooling water pipe for cooling. Among them, since the process cooling water absorbs the heat of the crystal growth furnace and heats up and returns to the water tank to transfer the heat to the medium in the heat exchanger, the medium that has absorbed the heat and heated up is transported to the heat exchanger through the return pipe. The phase change material can absorb the heat to achieve vaporization, and at the same time the heat exchanger After the temperature of the medium in the furnace is reduced, it is transported to the heat exchanger through the water inlet pipe to cool down the heated process cooling water, thereby realizing the entire circulating cooling process. Compared with the existing technology, this system uses the vaporization of phase change materials as a driving source to drive the process cooling water to cool the crystal growth furnace, ensuring the circulation of the process cooling water in the event of a sudden power outage in the crystal growth furnace, ensuring that the temperature of the crystal growth furnace is controllable, and the cold energy released when the phase change material vaporizes participates in the cooling process of the process cooling water, reducing dependence on external refrigerators, improving energy utilization efficiency, and increasing the cooling efficiency and stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 This is a flow path schematic diagram of the pneumatic PCW emergency cooling water circulation system of the embodiment of the present application when one of the water tanks is used as a water outlet tank;

[0025] Figure 2 This is a schematic diagram of the flow path of the pneumatic PCW emergency cooling water circulation system in an embodiment of the present application when another water tank is used as an outlet tank.

[0026] Icons: 10-storage tank; 20-vaporizer; 21-housing; 22-heat exchanger; 30-water tank assembly; 31-water tank; 310-exhaust valve; 32-heat exchanger; 40-infusion pipe; 400-on-off valve; 41-inlet pipe; 410-inlet valve; 411-pressure regulating valve; 42-process cooling water pipe; 43-water inlet pipe; 44-return pipe; 45-pneumatic pump; 46-air supply pipe; 50-crystal growth furnace. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0029] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0030] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0031] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0032] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0034] Combination Figure 1 and Figure 2 , the embodiment of the present application discloses a pneumatic PCW emergency cooling water circulation system, which includes a storage tank 10, a vaporizer 20 and a water tank assembly 30;

[0035] The storage tank 10 is used to store phase change material;

[0036] The vaporizer 20 includes a shell 21 and a heat exchanger 22 disposed in the shell 21, and the shell 21 is connected to the storage tank 10 through a liquid infusion pipe 40; the water tank assembly 30 includes a water tank 31 and a heat exchanger 32 disposed in the water tank 31, the upper part of the water tank 31 is connected to the shell 21 through an air inlet pipe 41, and the lower part of the water tank 31 is used to connect the cooling and heat dissipation coil of the crystal growth furnace 50 through a process cooling water pipe 42; the heat exchanger 32 is connected to the heat exchanger 22 through a water inlet pipe 43 and a water return pipe 44 to form a water circulation loop;

[0037] The phase change material can absorb the heat of the heat exchanger 22 and vaporize.

[0038] In this way, after the liquid phase change material in the storage tank 10 is input into the shell 21 through the liquid infusion pipe 40, it is vaporized by absorbing the heat of the heat exchanger 22, and the gaseous phase change material enters the upper area of ​​the water tank 31 through the air inlet pipe 41 to exert pressure on the process cooling water in the water tank 31, forcing the process cooling water to be transported to the crystal growth furnace 50 through the process cooling water pipe 42 for cooling. In which, since the process cooling water absorbs the heat of the crystal growth furnace 50 and heats up and returns to the water tank 31 to transfer the heat to the medium in the heat exchanger 32, the medium that has heated up after absorbing the heat is transported to the heat exchanger 22 through the return pipe 44, and the phase change material can absorb the heat to realize The medium in the heat exchanger 22 is vaporized, and the medium temperature is reduced and then transported to the heat exchanger 32 through the water inlet pipe 43 to cool the heated process cooling water, thereby realizing the entire circulating cooling process. Compared with the prior art, the system uses the vaporization of phase change material as a driving source to drive the process cooling water to cool the crystal growth furnace 50, ensuring the circulation of the process cooling water in the crystal growth furnace 50 in the event of a sudden power outage, ensuring the controllable temperature of the crystal growth furnace 50, and the cold energy released when the phase change material is vaporized participates in the cooling process of the process cooling water, reducing the dependence on external refrigerators, improving energy utilization efficiency, and increasing the cooling efficiency and stability of the system.

[0039] The phase change material can be liquid nitrogen, which is clean energy and low cost; of course, it can also be other substances that are gaseous at room temperature, such as liquid helium, etc.

[0040] The liquid delivery pipe 40 may be provided with a switch valve 400 to select whether liquid nitrogen is used to deliver the phase change material into the housing 21 of the vaporizer 20 by opening or closing the switch valve 400 .

[0041] Optionally, the pneumatic PCW emergency cooling water circulation system includes two water tank assemblies 30, each water tank 31 is connected to the liquid nitrogen vaporizer 20 through a corresponding nitrogen pipeline, and is connected to the crystal growth furnace 50 through a process cooling water pipe 42. At the same time, the heat exchanger 32 also forms a water circulation pipeline with the heat exchanger 22 through a corresponding water inlet pipe 43 and a water return pipe 44, that is, the two heat exchangers 32 are connected in parallel to the heat exchanger 22, and the two water tanks 31 are connected in parallel between the vaporizer 20 and the crystal growth furnace 50. The water tank 31 of one of the water tank assemblies 30 is used as an outlet water tank 31 to transport cooling water to the crystal growth furnace 50, and the water tank 31 of the other water tank assembly 30 is used as a return water tank 31 to recover the process cooling water heated by absorbing the heat of the crystal growth furnace 50.

[0042] In this way, the two water tanks 31 can alternately serve as the water outlet tank 31 and the water return tank 31, ensuring that the cooling cycle between the crystal growth furnace 50 can continue to operate, thereby continuously providing a stable cooling cycle for the crystal growth furnace 50, ensuring that the temperature of the crystal growth furnace 50 is controlled within an ideal range, and ensuring the continuity and high quality of crystal growth.

[0043] Of course, in order to be able to alternately drive the process cooling water in the two water tanks 31 to pass to the crystal growth furnace 50, an air intake valve 410 is respectively provided on the corresponding air intake pipes 41 of the two water tanks 31, that is, the two air intake pipes 41 are both provided with an air intake valve 410, and the air intake valves 410 on the two air intake pipes 41 can be opened one by one. In this way, the air intake valve 410 on one of the air intake pipes 41 is selected to be opened, and the water tank 31 connected to the air intake pipe 41 is used as the water outlet tank 31. At this time, the air intake valve 410 on the other air intake pipe 41 is closed, and the water tank 31 connected to the air intake pipe 41 is used as the return water tank 31. In this way, the two water tanks 31 can be alternately switched as the water outlet tank 31 by selectively opening one of the two air intake valves 410.

[0044] It can be understood that as the water level in the return water tank 31 gradually increases, the volume occupied by the gaseous phase change material gradually decreases, while the water level in the water storage tank 31 gradually decreases, the volume occupied by the gaseous phase change material gradually increases. In order to ensure normal return water from the crystal growth furnace 50 to the water tank 31 and prevent the gaseous phase change material in the water tank 31 from continuing to exert pressure on the process cooling water, an exhaust valve 310 can be provided on the water tank 31. When a certain water tank 31 is used as a return water tank 31, the exhaust valve 310 is opened, and the high-pressure gaseous phase change material is discharged through the exhaust valve 310, thereby reducing the pressure in the water tank 31. In this way, the process cooling water that has absorbed the heat of the crystal growth furnace 50 and heated up can flow back to the return water tank 31.

[0045] Of course, the exhaust valve 310 can be connected to other equipment in the workshop that needs high-pressure gas through a pipeline, so as to achieve recycling.

[0046] Among them, the water tank 31 is at least partially made of transparent material and is provided with water level scale lines, so that the staff can directly determine the water level in the water tank 31 through the water level scale lines, and switch one of the two air inlet valves 410 to open accordingly, to ensure that the water level of the process cooling water in the water tank 31 is not too low or too high.

[0047] In addition, in some embodiments, only one water tank 31 may be provided, and the water tank 31 has two enclosed water storage spaces. Each water storage space has a heat exchanger 32 and a corresponding exhaust valve 310, scale lines, etc., so that the circulating supply of process cooling water can be achieved.

[0048] The air inlet pipe 41 is provided with a pressure regulating valve 411, so that the air pressure to the gaseous phase change material in the water tank 31 can be conveniently adjusted by the opening of the pressure regulating valve 411, ensuring that the pressure of the gaseous phase change material in the water tank 31 is sufficient to force the process cooling water to flow to the crystal growth furnace 50.

[0049] Of course, the above-mentioned intake valve 410, switch valve 400, pressure regulating valve 411 and exhaust valve 310 are all pneumatic valves or manual valves to reduce dependence on electricity. In places where there is a lack of power supply or the power is unstable, the valves can still work reliably.

[0050] In order to realize water circulation among the heat exchanger 32, the water inlet pipe 43, the return pipe 44 and the heat exchanger 22, a pneumatic pump 45 is provided in the water inlet pipe 43 or the return pipe 44. The pneumatic pump 45 can be directly driven by the high-pressure nitrogen in the workshop to reduce the dependence on electricity. In places where there is a lack of power supply or the power is unstable, the pneumatic pump 45 can still work reliably.

[0051] Optionally, the housing 21 is connected to the pneumatic pump 45 via an air supply pipe 46 , so that the gaseous phase change material in the housing 21 of the vaporizer 20 can be supplied to the pneumatic pump 45 to assist the operation of the pneumatic pump 45 .

[0052] In summary, the embodiment of the present application discloses a pneumatic PCW emergency cooling water circulation system, which uses the vaporization of phase change material as a driving source to drive the process cooling water to cool the crystal growth furnace 50, thereby ensuring the process cooling water circulation of the crystal growth furnace 50 in the event of a sudden power outage, ensuring that the temperature of the crystal growth furnace 50 is controllable, and the cold energy released when the phase change material vaporizes participates in the cooling process of the process cooling water, thereby reducing dependence on external refrigerators, improving energy utilization efficiency, and increasing the cooling efficiency and stability of the system.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A pneumatic PCW emergency cooling water circulation system, characterized in that: It comprises a storage tank (10), a vaporizer (20) and a water tank assembly (30); The storage tank (10) is used to store phase change material; The vaporizer (20) comprises a shell (21) and a heat exchanger (22) arranged in the shell (21), and the shell (21) is connected to the storage tank (10) via a liquid infusion tube (40); The water tank assembly (30) comprises a water tank (31) and a heat exchanger (32) arranged in the water tank (31); the upper part of the water tank (31) is connected to the outer shell (21) via an air inlet pipe (41), and the lower part of the water tank (31) is used to connect to the crystal growth furnace (50) via a process cooling water pipe (42); the heat exchanger (32) is connected to the heat exchanger (22) via a water inlet pipe (43) and a water return pipe (44) to form a water circulation loop; The phase change material can absorb the heat of the heat exchanger (22) and vaporize.

2. The pneumatic PCW emergency cooling water circulation system according to claim 1 is characterized in that: The pneumatic PCW emergency cooling water circulation system comprises two water tank assemblies (30), wherein the water tank (31) of one of the water tank assemblies (30) serves as an outlet water tank (31) for delivering cooling water to the crystal growth furnace (50), and the water tank (31) of the other water tank assembly (30) serves as a return water tank (31) for recovering cooling water heated by absorbing heat from the crystal growth furnace (50).

3. The pneumatic PCW emergency cooling water circulation system according to claim 2 is characterized in that: The two air intake pipes (41) are both provided with an air intake valve (410), and the air intake valve (410) on the two air intake pipes (41) can be selectively opened.

4. The pneumatic PCW emergency cooling water circulation system according to claim 3 is characterized in that: The water tank (31) is at least partially made of a transparent material and is provided with water level scale lines.

5. The pneumatic PCW emergency cooling water circulation system according to claim 1 is characterized in that: The air inlet pipe (41) is provided with a pressure regulating valve (411).

6. The pneumatic PCW emergency cooling water circulation system according to claim 1 is characterized in that: The infusion tube (40) is provided with a switch valve (400).

7. The pneumatic PCW emergency cooling water circulation system according to claim 1 is characterized in that: The water inlet pipe (43) or the water return pipe (44) is provided with a pneumatic pump (45).

8. The pneumatic PCW emergency cooling water circulation system according to claim 7 is characterized in that: The housing (21) is in communication with the pneumatic pump (45) via an air supply pipe (46).

9. The pneumatic PCW emergency cooling water circulation system according to claim 1 is characterized in that: The water tank (31) is provided with an exhaust valve (310).

10. The pneumatic PCW emergency cooling water circulation system according to claim 1 is characterized in that: The phase change material is liquid nitrogen.

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