Single crystal furnace

Abstract

The utility model provides a single crystal furnace, which comprises a single crystal furnace body, a single crystal furnace cover and a single crystal furnace cover, the exhaust pipe is arranged at the bottom of the single crystal furnace body and is used for exhausting the inert gas; the safety device is arranged at the bottom of the single crystal furnace body and is communicated with the exhaust pipe, and the content of the inert gas in the exhaust pipe is adjusted to be below a threshold value after the single crystal furnace is shut down. According to the single crystal furnace provided by the embodiment of the utility model, the safety coefficient can be effectively improved, and a suffocation safety accident caused by the fact that personnel enter the furnace when the furnace is shut down for operation is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of single crystal furnaces, in particular to a single crystal furnace. Background Art

[0002] When the single crystal furnace is pulling single crystals, the furnace body is in a high-temperature vacuum environment. Due to the needs of the process, inert gas will be input into the furnace, combined with the vacuum pump's exhaust, to form an inert gas flow under a reduced pressure atmosphere. The inert gas used in the single crystal furnace is colorless, non-toxic, odorless, non-flammable and non-combustible. It has the function of taking away impurities volatilized from the silicon solution and protecting the crystal rod from oxidation. However, the density of inert gas is greater than that of air. When the single crystal furnace is in a shutdown state and the pressure difference between the inside and outside of the furnace is the same, a large amount of inert gas inside the single crystal furnace will be deposited at the bottom of the furnace. If the cleaning or maintenance personnel enter the furnace body to work at this time, there will be a risk of suffocation accidents. Due to the colorless and odorless chemical properties of the inert gas used in the single crystal furnace and the weak safety awareness of the personnel, in the actual crystal pulling production process, suffocation accidents caused by the high concentration of inert gas in the furnace often occur. Utility Model Content

[0003] In view of this, the utility model provides a single crystal furnace, which can effectively improve the safety factor and avoid suffocation accidents caused by personnel entering the furnace during furnace shutdown operations.

[0004] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0005] The single crystal furnace according to the embodiment of the utility model comprises:

[0006] A single crystal furnace body, into which an inert gas is introduced;

[0007] An exhaust pipe, which is disposed at the bottom of the single crystal furnace body and discharges the inert gas;

[0008] A safety device is arranged at the bottom of the single crystal furnace body and is connected to the exhaust pipe. After the furnace is shut down, the content of the inert gas in the exhaust pipe is adjusted to be below a threshold.

[0009] Furthermore, the safety device comprises:

[0010] A plunger pump, the plunger pump being in communication with the exhaust pipe;

[0011] a sensor connected between the plunger pump and the exhaust pipe to detect the inert gas content in the exhaust pipe,

[0012] Wherein, the plunger pump adjusts the content of the inert gas in the exhaust pipe to be below a threshold value after the furnace is shut down according to the content of the inert gas in the exhaust pipe detected by the sensor.

[0013] Furthermore, the plunger pump comprises:

[0014] A plunger pump cylinder body, wherein a cavity is formed in the plunger pump cylinder body, one end of the cavity is connected to an air intake pipe, and the other end is connected to an exhaust pipe, and the air intake pipe is connected to the exhaust pipe;

[0015] A switch valve, the switch valve is connected between the air intake pipe and the cavity to control the opening and closing of the air intake pipe and the cavity;

[0016] A plunger, wherein the plunger is disposed in the cavity of the plunger pump cylinder body and can expand or reduce the volume of the cavity by rotating to form a negative pressure or a positive pressure in the cavity, wherein the inert gas is sucked from the air intake pipe when a negative pressure is formed in the cavity, and the inert gas is discharged from the cavity to the exhaust pipe when a positive pressure is formed in the cavity;

[0017] A driving part is connected to the plunger to drive the plunger to rotate.

[0018] Furthermore, when the plunger rotates in a first direction, the volume of the cavity is expanded; when the plunger rotates in a second direction opposite to the first direction, the volume of the cavity is reduced, so that a positive pressure is formed in the cavity.

[0019] Furthermore, the sensor is arranged on the air intake pipe.

[0020] Furthermore, there are multiple plungers.

[0021] Furthermore, when the sensor detects that the inert gas content in the exhaust pipe remains unchanged, it is determined that the single crystal furnace is shut down.

[0022] Furthermore, when the plunger rotates to expand the volume of the cavity, the switch valve opens; when the plunger rotates to reduce the volume of the cavity, the switch valve closes.

[0023] Furthermore, it comprises two exhaust pipes extending vertically and arranged in parallel, and each of the exhaust pipes is connected to one of the safety devices.

[0024] Furthermore, the single crystal furnace further comprises:

[0025] An exhaust cross pipe, which extends transversely and is disposed at the bottom ends of the two exhaust pipes, is communicated with the bottom ends of the two exhaust pipes, and is communicated with the exhaust duct of each of the safety devices;

[0026] An exhaust vertical pipe extends vertically, with an upper end connected to the exhaust cross pipe and a lower end connected to an exhaust device for exhaust.

[0027] The above technical solution of the utility model has at least one of the following beneficial effects:

[0028] According to the single crystal furnace of the embodiment of the utility model, inert gas is passed through the furnace body of the single crystal furnace and an exhaust pipe is provided at the bottom. By arranging the safety device at the bottom of the furnace body of the single crystal furnace and connecting it with the exhaust pipe, the content of inert gas in the exhaust pipe can be adjusted below the threshold after the furnace is stopped. Therefore, through the synergistic effect of the safety device at the bottom of the furnace body of the single crystal furnace and the exhaust pipe, the internal inert gas content of the single crystal furnace when the furnace is stopped is effectively controlled, the safety factor of the single crystal furnace is improved, and the suffocation safety accident caused by personnel entering the furnace during the shutdown operation is avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of a single crystal furnace according to an embodiment of the present utility model;

[0030] Figure 2 This is a schematic diagram of a safety device in a single crystal furnace according to an embodiment of the utility model.

[0031] Reference numerals: 100. safety device; 110. plunger pump; 111. plunger pump cylinder; 112. air intake pipe; 113. exhaust pipe; 114. switch valve; 115. plunger; 120. sensor;

[0032] 200. Exhaust pipe;

[0033] 300. Exhaust cross pipe;

[0034] 400. Exhaust standpipe;

[0035] 500. Single crystal furnace body. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution of the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings of the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the described embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the utility model.

[0037] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the usual meanings understood by persons with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not indicate quantity restrictions, but indicate the existence of at least one. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship also changes accordingly.

[0038] The single crystal furnace according to the embodiment of the utility model is first described in detail below with reference to the accompanying drawings.

[0039] Figure 1 A schematic diagram of a single crystal furnace according to an embodiment of the utility model is shown.

[0040] like Figure 1 As shown, the single crystal furnace according to the embodiment of the present invention may include: a single crystal furnace body 500 , an exhaust pipe 200 and a safety device 100 .

[0041] Specifically, inert gas is introduced into the single crystal furnace body 500. The exhaust pipe 200 is arranged at the bottom of the single crystal furnace body 500 and discharges the inert gas. The safety device 100 is arranged at the bottom of the single crystal furnace body 500 and communicates with the exhaust pipe 200, and adjusts the content of the inert gas in the exhaust pipe 200 to be below the threshold after the furnace is stopped.

[0042] That is, when the single crystal furnace is in operation, inert gas is introduced into the furnace body to create an inert atmosphere for crystal pulling, the exhaust pipe 200 is arranged at the bottom of the single crystal furnace body 500 to discharge the used inert gas, the safety device 100 is arranged at the bottom of the single crystal furnace body 500 and is connected to the exhaust pipe 200, and the inert gas content in the exhaust pipe 200 is adjusted below the threshold value after the single crystal furnace is stopped. Therefore, through the synergistic effect of the safety device 100 at the bottom of the single crystal furnace body 500 and the exhaust pipe 200, the internal inert gas content of the single crystal furnace when it is stopped is effectively controlled, the safety factor of the single crystal furnace is improved, and the suffocation safety accident caused by personnel entering the furnace during the shutdown operation is avoided.

[0043] Figure 2 FIG. 1 is a schematic diagram of a safety device 100 according to an embodiment of the present invention.

[0044] In some embodiments of the present invention, Figure 2As shown, the safety device 100 may include: a plunger pump 110 and a sensor 120. The plunger pump 110 is in communication with the exhaust pipe 200, and the sensor 120 is connected between the plunger pump 110 and the exhaust pipe 200 to detect the inert gas content in the exhaust pipe 200, and the plunger pump 110 adjusts the inert gas content in the exhaust pipe 200 to be below the threshold after the furnace is shut down according to the inert gas content in the exhaust pipe 200 detected by the sensor 120.

[0045] Here, it should be noted that the sensor 120 can detect the inert gas content in the exhaust pipe 200 in real time. When inert gas flows into or out of the exhaust pipe 200 at the bottom of the single crystal furnace body 500, in this case, the inert gas content detected by the sensor 120 is constantly fluctuating, and the single crystal furnace is judged to be in operation at this time. When the inert gas content detected by the sensor 120 remains stable for a certain period of time, the single crystal furnace is judged to be in a shutdown state at this time.

[0046] In some embodiments of the present invention, Figure 2 As shown, the plunger pump 110 includes: a plunger pump cylinder 111, a switch valve 114, a plunger 115 and a driving unit. A cavity is formed in the plunger pump cylinder 111, one end of the cavity is connected to an air intake pipe 112, and the other end is connected to an exhaust pipe 113, and the air intake pipe 112 is connected to the exhaust pipe 200. The switch valve 114 is connected between the air intake pipe 112 and the cavity to control the connection and disconnection between the air intake pipe 112 and the cavity. The plunger 115 is arranged in the cavity of the plunger pump cylinder 111, and the volume of the cavity can be expanded or reduced by rotation to form a negative pressure or a positive pressure in the cavity. When a negative pressure is formed in the cavity, an inert gas is sucked from the air intake pipe 112, and when a positive pressure is formed in the cavity, the inert gas is discharged from the cavity to the exhaust pipe 113. The driving unit is connected to the plunger 115 to drive the plunger 115 to rotate.

[0047] Argon is usually used as the inert gas inside the single crystal furnace. Taking the set safety standard, that is, the argon concentration needs to be lower than 20% (when the argon concentration in the air is higher than 33%, there is a risk of suffocation) as an example, the operation of the single crystal furnace safety device 100 is briefly described: when the sensor 120 detects that the argon content in the exhaust pipe 200 is constantly fluctuating, it means that the single crystal furnace is in a non-shutdown state, and the plunger pump 110 does not need to work at this time. When the sensor 120 detects that the argon content in the exhaust pipe 200 remains stable for a certain period of time, it means that the single crystal furnace is in a shutdown state. At this time, the plunger pump 110 automatically opens the switch valve 114 according to the detection signal of the sensor 120 (argon concentration is greater than or equal to 20%) to start working. The driving unit provides power, and the plunger 115 in the plunger pump 110 rotates to expand the cavity volume in the plunger pump cylinder 111 to form a negative pressure in the cavity, and then the pressure difference is used to suck the argon gas at the bottom of the furnace through the exhaust pipe 200 and the intake pipe 112 in turn. After that, the plunger 115 in the plunger pump 110 rotates again to reduce the cavity volume in the plunger pump cylinder 111 to form a positive pressure in the cavity, and then the pressure difference is used to discharge the argon gas from the cavity to the exhaust pipe 113. Until the sensor 120 detects that the argon concentration is lower than 20%, the switch valve 114 is closed, and the plunger pump 110 stops working and shuts down. Through the synergistic effect of the plunger pump 110 and the sensor 120, real-time monitoring of the internal gas pressure and inert gas content of the single crystal furnace when it is shut down is achieved, and control is implemented according to the monitoring results, thereby effectively improving the safety factor of the single crystal furnace and avoiding suffocation accidents caused by personnel entering the furnace during shutdown operations.

[0048] It should be noted here that the setting of safety standards can be appropriately changed according to specific requirements. The purpose of this application is to provide a safety device 100 for real-time monitoring of the internal inert gas content when a single crystal furnace is shut down and implementing control (forced exhaust) based on the monitoring results. No limitation is made on the safety standard itself.

[0049] In some other embodiments of the utility model, the safety device 100 may also include: a control system (not shown). The control system is connected to the sensor 120 to read the pressure and argon content measured by the sensor 120. The control system is also connected to the plunger pump 110 to control the plunger pump 110 to turn on / off according to the pressure and argon content. By setting up a control system, the status of the sensor 120 and the plunger pump 110 can be monitored and fed back in time, so that the operator can understand the operating status of the safety device 100 in time to facilitate fault diagnosis or predictive maintenance. At the same time, the safety device 100 can be remotely monitored and controlled through the control system, further improving the safety and stability of the single crystal furnace.

[0050] In some embodiments of the present invention, Figure 2As shown, the X direction represents the first direction. When the plunger 115 rotates in the first direction, the volume of the cavity is expanded; when the plunger 115 rotates in a second direction opposite to the first direction, the volume of the cavity is reduced, so that a positive pressure is formed in the cavity.

[0051] That is to say, Figure 2 As shown, the plunger 115 in the plunger pump 110 gradually extends outwards during the half-circle of its rotation from bottom to top, so that the volume of the sealed working chamber in the plunger pump 110 cavity continues to increase, forming a partial vacuum, and the inert gas at the bottom of the furnace body is sucked in by the pressure difference. The plunger 115 then gradually pushes inwards during the half-circle of its rotation from top to bottom, so that the volume of the sealed working chamber continues to decrease, and then the inert gas is discharged outwards. In this way, the cyclic suction and discharge of the inert gas can be achieved, thereby effectively removing the inert gas deposited at the bottom of the furnace body.

[0052] In some embodiments of the present invention, Figures 1 to 2 As shown, the sensor 120 is arranged on the air intake pipe 112. Since the air intake pipe 112 is connected to the exhaust pipe 200, the inert gas content in the furnace can be detected regardless of whether the sensor 120 is located between the plunger pump 110 and the exhaust pipe 200 or directly connected to the air intake pipe 112. Connecting the sensor 120 to the air intake pipe 112 is more convenient for maintenance, and further improves the stability and reliability of the single crystal furnace safety device 100.

[0053] In some embodiments of the present invention, Figure 2 As shown, there are multiple plungers 115. Specifically, the multiple plungers 115 are slidably disposed in the chamber of the plunger pump cylinder 111, which can deliver more inert gas in a shorter time, and help improve the efficiency of exhaust.

[0054] In some embodiments of the present invention, when the sensor 120 detects that the inert gas content in the exhaust pipe 200 remains unchanged, it is determined that the single crystal furnace is shut down.

[0055] Here, it should be supplemented that, since the sensor 120 can detect the inert gas content in the exhaust pipe 200 in real time, the so-called detection of the inert gas content in the exhaust pipe 200 "remaining unchanged" here means that the inert gas content does not change within a certain period of time, and the certain period of time can be 1 hour, 2 hours, 3 hours or 4 hours, etc. For example, the normal shutdown time of the single crystal furnace is 10 hours. During the 10-hour period, there will be inert gas flow before 6 hours, and there will be no inert gas flow in the following 4 hours. Then, at this time, a certain time can be set to be selected within 4 hours, such as judging that the single crystal furnace is shut down if the inert gas content is stable within 2 hours. For the setting of a certain time here, this application does not limit this, and can be adaptively selected and judged according to the shutdown stabilization time after the actual operation on site.

[0056] In addition, in some other embodiments of the utility model, a pressure sensor 120 can be added on the basis of the inert gas content detection sensor 120 to detect the pressure in the exhaust pipe 113. When it is detected that the exhaust pipe 200 is in a normal pressure state (that is, the internal and external pressure difference is consistent with the normal atmospheric pressure) and there is no gas flow, it can be determined that the single crystal furnace is in a shutdown state.

[0057] In some embodiments of the present invention, when the plunger 115 rotates to expand the volume of the cavity, the switch valve 114 is opened. When the plunger 115 rotates to reduce the volume of the cavity, the switch valve 114 is closed. By controlling the rotation of the plunger 115 and the state of the switch valve 114, the regulation of the inert gas discharge is achieved, which is simple and effective.

[0058] In some embodiments of the present invention, two exhaust pipes 200 extending vertically and arranged in parallel are included, and each exhaust pipe 200 is connected to a safety device 100 .

[0059] That is, by providing a pair of exhaust pipes 200 and connecting a pair of safety devices 100 to both sides of the pair of exhaust pipes 200 in a one-to-one correspondence, it is helpful to improve the balance of exhaust and further improve the exhaust efficiency.

[0060] In some embodiments of the present invention, the single crystal furnace further includes: an exhaust cross pipe 300 and an exhaust vertical pipe 400. The exhaust cross pipe 300 extends horizontally and is arranged at the bottom ends of the two exhaust pipes 200, is connected to the bottom ends of the two exhaust pipes 200, and is connected to the exhaust pipe 113 of each safety device 100. The exhaust vertical pipe 400 extends vertically, and the upper end is connected to the exhaust cross pipe 300 and the lower end is connected to the exhaust device for exhaust. By setting the exhaust cross pipe 300, it is more convenient to clean the volatiles in the pipeline, and by setting the exhaust vertical pipe 400, the gas that needs to be discharged can be collected and then discharged through the exhaust device.

[0061] The above is a preferred embodiment of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A single crystal furnace, characterized in that: include: A single crystal furnace body, into which an inert gas is introduced; An exhaust pipe, which is disposed at the bottom of the single crystal furnace body and discharges the inert gas; A safety device is arranged at the bottom of the single crystal furnace body and is connected to the exhaust pipe. After the furnace is shut down, the content of the inert gas in the exhaust pipe is adjusted to be below a threshold.

2. The single crystal furnace according to claim 1, characterized in that: The safety device comprises: A plunger pump, the plunger pump being in communication with the exhaust pipe; a sensor connected between the plunger pump and the exhaust pipe to detect the inert gas content in the exhaust pipe, Wherein, the plunger pump adjusts the content of the inert gas in the exhaust pipe to be below a threshold value after the furnace is shut down according to the content of the inert gas in the exhaust pipe detected by the sensor.

3. The single crystal furnace according to claim 2, characterized in that: The plunger pump comprises: A plunger pump cylinder body, wherein a cavity is formed in the plunger pump cylinder body, one end of the cavity is connected to an air intake pipe, and the other end is connected to an exhaust pipe, and the air intake pipe is connected to the exhaust pipe; A switch valve, the switch valve is connected between the air intake pipe and the cavity to control the opening and closing of the air intake pipe and the cavity; A plunger, wherein the plunger is disposed in the cavity of the plunger pump cylinder body and can expand or reduce the volume of the cavity by rotating to form a negative pressure or a positive pressure in the cavity, wherein the inert gas is sucked from the air inlet pipe when a negative pressure is formed in the cavity, and the inert gas is discharged from the cavity to the exhaust pipe when a positive pressure is formed in the cavity; A driving part is connected to the plunger to drive the plunger to rotate.

4. The single crystal furnace according to claim 3, characterized in that: When the plunger rotates in a first direction, the volume of the cavity is expanded; when the plunger rotates in a second direction opposite to the first direction, the volume of the cavity is reduced, so that a positive pressure is formed in the cavity.

5. The single crystal furnace according to claim 4, characterized in that: The sensor is arranged on the air intake pipe.

6. The single crystal furnace according to claim 5, characterized in that: The number of the plungers is multiple.

7. The single crystal furnace according to claim 6, characterized in that: When the sensor detects that the inert gas content in the exhaust pipe remains unchanged, it is determined that the single crystal furnace is shut down.

8. The single crystal furnace according to claim 7, characterized in that: When the plunger rotates to expand the volume of the cavity, the switch valve opens; when the plunger rotates to reduce the volume of the cavity, the switch valve closes.

9. The single crystal furnace according to claim 8, characterized in that: It comprises two exhaust pipes extending vertically and arranged in parallel, and each of the exhaust pipes is connected to one of the safety devices.

10. The single crystal furnace according to claim 9, characterized in that: Also includes: An exhaust cross pipe, which extends transversely and is disposed at the bottom ends of the two exhaust pipes, is communicated with the bottom ends of the two exhaust pipes, and is communicated with the exhaust duct of each of the safety devices; An exhaust vertical pipe extends vertically, with an upper end connected to the exhaust cross pipe and a lower end connected to an exhaust device for exhaust.

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